A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

              [Sort alphabetically]   [Restore default list]

  Subjects -> CONSERVATION (Total: 128 journals)
Showing 1 - 37 of 37 Journals sorted by number of followers
Conservation Biology     Hybrid Journal   (Followers: 279)
Biological Conservation     Hybrid Journal   (Followers: 247)
Biodiversity and Conservation     Open Access   (Followers: 195)
Ecological Economics     Hybrid Journal   (Followers: 142)
Ecology and Evolution     Open Access   (Followers: 100)
Global Ecology and Biogeography     Hybrid Journal   (Followers: 65)
Environmental Conservation     Hybrid Journal   (Followers: 63)
Ecology and Society     Open Access   (Followers: 50)
Frontiers in Ecology and Evolution     Open Access   (Followers: 48)
Animal Conservation     Hybrid Journal   (Followers: 48)
Functional Ecology     Hybrid Journal   (Followers: 48)
Restoration Ecology     Hybrid Journal   (Followers: 46)
Aquatic Conservation Marine and Freshwater Ecosystems     Hybrid Journal   (Followers: 44)
Diversity and Distributions     Open Access   (Followers: 43)
Landscape and Urban Planning     Hybrid Journal   (Followers: 36)
Nature Conservation     Open Access   (Followers: 35)
Conservation Science     Open Access   (Followers: 29)
Environmental and Resource Economics     Hybrid Journal   (Followers: 29)
Conservation     Hybrid Journal   (Followers: 28)
Journal for Nature Conservation     Hybrid Journal   (Followers: 27)
Journal of the Institute of Conservation     Hybrid Journal   (Followers: 25)
Conservation Genetics     Hybrid Journal   (Followers: 22)
Ecological Restoration     Full-text available via subscription   (Followers: 22)
Society & Natural Resources: An International Journal     Hybrid Journal   (Followers: 21)
Forest Policy and Economics     Hybrid Journal   (Followers: 21)
Journal of Rural Studies     Hybrid Journal   (Followers: 20)
Oryx     Open Access   (Followers: 20)
Resources, Conservation & Recycling     Hybrid Journal   (Followers: 20)
Journal of Industrial Ecology     Hybrid Journal   (Followers: 18)
Wildlife Research     Hybrid Journal   (Followers: 18)
International Journal of Sustainable Development     Hybrid Journal   (Followers: 17)
African Journal of Ecology     Hybrid Journal   (Followers: 17)
Studies in Conservation     Hybrid Journal   (Followers: 16)
Nature Sustainability     Hybrid Journal   (Followers: 15)
Lakes & Reservoirs Research & Management     Hybrid Journal   (Followers: 14)
Global Ecology and Conservation     Open Access   (Followers: 13)
Journal for the Study of Religion, Nature and Culture     Hybrid Journal   (Followers: 12)
African Journal of Range & Forage Science     Hybrid Journal   (Followers: 12)
Wildfowl     Open Access   (Followers: 11)
Bulletin of the American Museum of Natural History     Open Access   (Followers: 10)
Arid Land Research and Management     Hybrid Journal   (Followers: 10)
Business Strategy and the Environment     Hybrid Journal   (Followers: 10)
Challenges in Sustainability     Open Access   (Followers: 10)
Journal of Natural Resources Policy Research     Hybrid Journal   (Followers: 10)
African Journal of Wildlife Research     Full-text available via subscription   (Followers: 9)
Aquaculture, Aquarium, Conservation & Legislation - International Journal of the Bioflux Society     Open Access   (Followers: 9)
Ideas in Ecology and Evolution     Open Access   (Followers: 9)
Journal of Cultural Heritage Management and Sustainable Development     Hybrid Journal   (Followers: 8)
Earth's Future     Open Access   (Followers: 8)
International Journal of Global Energy Issues     Hybrid Journal   (Followers: 8)
International Journal of Sustainable Development and World Ecology     Hybrid Journal   (Followers: 8)
Journal of East African Natural History     Full-text available via subscription   (Followers: 7)
Natural Resources Forum     Hybrid Journal   (Followers: 7)
Advanced Sustainable Systems     Hybrid Journal   (Followers: 7)
Environmental and Sustainability Indicators     Open Access   (Followers: 7)
Human Dimensions of Wildlife: An International Journal     Hybrid Journal   (Followers: 6)
Natural Resources and Conservation     Open Access   (Followers: 6)
American Journal of Rural Development     Open Access   (Followers: 6)
International Journal of Architectural Heritage: Conservation, Analysis, and Restoration     Hybrid Journal   (Followers: 6)
International Journal of Biodiversity Science and Management     Open Access   (Followers: 6)
Journal of Urban Ecology     Open Access   (Followers: 6)
Environment and Planning E : Nature and Space     Hybrid Journal   (Followers: 5)
Journal of International Wildlife Law & Policy     Hybrid Journal   (Followers: 5)
Journal of Ecology and The Natural Environment     Open Access   (Followers: 5)
Ethnobiology and Conservation     Open Access   (Followers: 4)
Journal of the American Institute for Conservation     Hybrid Journal   (Followers: 4)
International Journal of Social Ecology and Sustainable Development     Full-text available via subscription   (Followers: 4)
Archeomatica     Open Access   (Followers: 4)
Environment Conservation Journal     Open Access   (Followers: 4)
Australasian Plant Conservation: Journal of the Australian Network for Plant Conservation     Full-text available via subscription   (Followers: 4)
AICCM Bulletin     Hybrid Journal   (Followers: 3)
Ecological Psychology     Hybrid Journal   (Followers: 3)
International Journal of Environment and Pollution     Hybrid Journal   (Followers: 3)
Journal of Sustainable Mining     Open Access   (Followers: 3)
Southern Forests : a Journal of Forest Science     Hybrid Journal   (Followers: 3)
Interdisciplinary Environmental Review     Hybrid Journal   (Followers: 3)
Neotropical Biology and Conservation     Open Access   (Followers: 2)
Journal of Paper Conservation     Hybrid Journal   (Followers: 2)
Asian Journal of Sustainability and Social Responsibility     Open Access   (Followers: 2)
Pacific Conservation Biology     Full-text available via subscription   (Followers: 2)
International Soil and Water Conservation Research     Open Access   (Followers: 2)
Sustainable Earth     Open Access   (Followers: 2)
Tanzania Journal of Forestry and Nature Conservation     Full-text available via subscription   (Followers: 2)
Madagascar Conservation & Development     Open Access   (Followers: 2)
Eastern European Countryside     Open Access   (Followers: 2)
Rural Sustainability Research     Open Access   (Followers: 2)
World Review of Entrepreneurship, Management and Sustainable Development     Hybrid Journal   (Followers: 1)
Conservation Science and Practice     Open Access   (Followers: 1)
Journal of Threatened Taxa     Open Access   (Followers: 1)
Rangeland Journal     Hybrid Journal   (Followers: 1)
Resources, Conservation & Recycling : X     Open Access   (Followers: 1)
Forum Journal     Full-text available via subscription   (Followers: 1)
Tropical Conservation Science     Open Access   (Followers: 1)
Conservación Vegetal     Open Access   (Followers: 1)
Park Watch     Full-text available via subscription   (Followers: 1)
Wildlife Australia     Full-text available via subscription   (Followers: 1)
European Countryside     Open Access   (Followers: 1)
In Situ. Revue des patrimoines     Open Access   (Followers: 1)
npj Urban Sustainability     Open Access  
Recursos Rurais     Open Access  
Madera y Bosques     Open Access  
Intervención     Open Access  
Soil Ecology Letters     Hybrid Journal  
Tropical Ecology     Hybrid Journal  
Socio-Ecological Practice Research     Hybrid Journal  
Process Integration and Optimization for Sustainability     Hybrid Journal  
Water Conservation Science and Engineering     Hybrid Journal  
Nepalese Journal of Development and Rural Studies     Open Access  
VITRUVIO : International Journal of Architectural Technology and Sustainability     Open Access  
Sustainable Environment Agricultural Science (SEAS)     Open Access  
Savana Cendana     Open Access  
Arcada : Revista de conservación del patrimonio cultural     Open Access  
Nusantara Bioscience     Open Access  
Indonesian Journal of Conservation     Open Access  
Indonesian Journal of Sustainability Accounting and Management     Open Access  
One Ecosystem     Open Access  
Revista de Direito e Sustentabilidade     Open Access  
Ambiens. Revista Iberoamericana Universitaria en Ambiente, Sociedad y Sustentabilidad     Open Access  
Revista Meio Ambiente e Sustentabilidade     Open Access  
Revista de Ciencias Ambientales     Open Access  
Recycling     Open Access  
Revista Memorare     Open Access  
Novos Cadernos NAEA     Open Access  
Julius-Kühn-Archiv     Open Access  
Future Anterior     Full-text available via subscription  
Regional Sustainability     Open Access  
Interações (Campo Grande)     Open Access  

              [Sort alphabetically]   [Restore default list]

Similar Journals
Journal Cover
Number of Followers: 0  

  This is an Open Access Journal Open Access journal
ISSN (Online) 2313-4321
Published by MDPI Homepage  [246 journals]
  • Recycling, Vol. 7, Pages 81: The Application of Artificial Intelligence in
           the Effective Battery Life Cycle in the Closed Circular Economy
           Model—A Perspective

    • Authors: Agnieszka Pregowska, Magdalena Osial, Weronika Urbańska
      First page: 81
      Abstract: Global pollution of the environment is one of the most challenging environmental problems. Electronic-based population and anthropogenic activity are the main reasons for dramatically increasing the scale of waste generation, particularly battery waste. Improper battery waste disposal causes harmful environmental effects. Due to the release of heavy metals, battery waste affects ecosystems and health. We are faced with the challenge of effective battery waste management, especially recycling, to prevent the depletion of natural resources and maintain ecological balance. Artificial Intelligence (AI) is practically present in all areas of our lives. It enables the reduction of the costs associated with various types of research, increases automation, and accelerates productivity. This paper reviews the representative research progress of effective Artificial Intelligence-based battery waste management in the context of sustainable development, in particular, the analysis of current trends, algorithm accuracy, and data availability. Finally, the future lines of research and development directions of human-oriented Artificial Intelligence applications both in the battery production process and in battery waste management are discussed.
      Citation: Recycling
      PubDate: 2022-11-07
      DOI: 10.3390/recycling7060081
      Issue No: Vol. 7, No. 6 (2022)
  • Recycling, Vol. 7, Pages 82: Environmental Impact Assessment of
           Construction Waste Recycling versus Disposal Scenarios Using an LCA-BIM
           Tool during the Design Stage

    • Authors: Carmen Llatas, Rocío Quiñones, Nuria Bizcocho
      First page: 82
      Abstract: The scientific community has revealed the environmental benefits of recycling construction waste (CW) versus its disposal, and its contribution to circularity. The Life Cycle Assessment (LCA) method enables the environmental impact of CW management to be quantified and facilitates the comparison of recycling versus alternative disposal scenarios. However, due to its complexity, LCA is seldom used by technicians during the design phase, which constitutes a crucial stage in the prevention of environmental impacts. This paper therefore proposes an LCA-based tool, integrated into the Building Information Modelling (BIM) methodology, that helps designers to automate the environmental assessment of recycling versus disposal. The CW-LCA-BIM tool uses impact factors obtained from an LCA model applied to CW and was applied to the structural system of a building in Spain. Up to 99% of the non-hazardous waste was recyclable or reusable. The management of three types of recyclable waste was assessed: concrete (27.2 t), plastics (4.2 t), and steel (1.5 t). Recycling is shown to be the best option since it prevents 1.4 times (14.6 t) the emissions of the disposal scenario and saves 85 times (148.5 GJ) its energy consumption. This tool can be developed in other waste management systems and infrastructures. It can be useful both for designers for the reduction of the environmental impact of their buildings, and for policy managers for waste-prevention policies.
      Citation: Recycling
      PubDate: 2022-11-07
      DOI: 10.3390/recycling7060082
      Issue No: Vol. 7, No. 6 (2022)
  • Recycling, Vol. 7, Pages 83: How Do Industrial Ecology, Energy Efficiency,
           and Waste Recycling Technology (Circular Economy) Fit into China’s
           Plan to Protect the Environment' Up to Speed

    • Authors: Sasmoko Sasmoko, Muhammad Zaheer Akhtar, Haroon ur Rashid Khan, Sriyanto Sriyanto, Mohd Khata Jabor, Awais Rashid, Khalid Zaman
      First page: 83
      Abstract: The challenges of environmental protection are especially prevalent in South and Southeast Asian nations, which adversely affects their sustainable developmental goals. During the last two decades, increased industrialization and urbanization have caused massive air pollution, particularly in the most industrialized and densely populated countries. Due to China’s fast economic expansion and development, the demand for natural resources has increased, resulting in climate change, biodiversity loss, soil degradation, and environmental risks. China’s ecological footprint has been the subject of little investigation on the premises of a circular economy. This study used a literature review methodology on the critical key factors that hinder or facilitate the transition of a linear economy towards a circular economy. Further, based on the literature review, this study used industrial ecology, energy efficiency, and waste recycling technology factors to analyze the role of the circular economy on the country’s environmental sustainability agenda for the period of 1975–2020. The results show that in the short run, the link between ecological footprints and per capita income is monotonically decreasing; however, in the long run, the relationship is U-shaped. In both the short and long run, waste recycling technology and cleaner manufacturing significantly decrease ecological footprints. Renewable energy consumption increases ecological footprints in the short run but decreases them in the long run. The management of natural resources reduces ecological footprints to support the ‘resource blessing’ hypothesis. The Granger causality corroborated the unidirectional relationship between ecological footprints, oil rents, and urbanization and ecological footprints. In addition, economic growth Granger causes industrialization and waste recycling technology while green energy Granger causes economic growth, industrialization, and recycling technology. The two-way link between economic development and urbanization exists within a nation. The variance decomposition analysis (VDA) predicts that in the future, China’s natural resources, green energy demand, and technological spillover will limit its ecological footprint through material and technology efficiency.
      Citation: Recycling
      PubDate: 2022-11-07
      DOI: 10.3390/recycling7060083
      Issue No: Vol. 7, No. 6 (2022)
  • Recycling, Vol. 7, Pages 84: Mineral Carbonation of Basic Oxygen Furnace

    • Authors: Daniel Vollprecht, Dominik Wohlmuth
      First page: 84
      Abstract: Mineral carbonation is a method in carbon capture and utilization (CCU) in which carbon dioxide reacts with natural or synthetic mineral phases to form carbonates. In this study, BOF slag consisting of alite, Ca3SiO5, belite, Ca2SiO4, melilite, (Ca,Na)2(Mg,Al)[Si2O7], brownmillerite, Ca(Fe,Al)2O5, calcium ferrite, Ca2FeO4 and Ca-, Mg- and Mn-bearing wuestite, (Mg,Ca,Mn,Fe)O, was crushed into different particle size fractions and exposed over various durations (1 d, 3 d, 9 d, 14 d, 24 d) at a grate to 120 °C hot off-gas with a CO2 content of 25%. However, the total inorganic carbon (TIC) content never increases above the detection limit of 0.5% throughout the experimental duration. The determination of the carbonation depth using phenolphthalein does not reveal a homogeneous carbonation front, but an irregular carbonation. This observation was confirmed by microprobe analyses using elemental mapping. The solubility of the slag increases with increasing carbonation, e.g., the leachability of sulfate increases from 7.8 to 8270 mg/kg dry matter (DM), and of calcium from 940 to 3860 mg/kg DM. The leaching of environmentally relevant element varies: the leachable concentration of molybdenum increases from 0.017 mg/kg DM to 0.089 mg/kg DM, that of chromium remains constant (ca. 0.05 mg/kg DM) whereas that of vanadium decreases from 1.1 to 0.45 mg/kg. In summary, the chosen carbonation technology must be improved to enhance carbonate yield.
      Citation: Recycling
      PubDate: 2022-11-07
      DOI: 10.3390/recycling7060084
      Issue No: Vol. 7, No. 6 (2022)
  • Recycling, Vol. 7, Pages 85: Asbestos Waste Treatment—An Effective
           Process to Selectively Recover Gold and Other Nonferrous Metals

    • Authors: Omirserik Baigenzhenov, Alibek Khabiyev, Brajendra Mishra, Indira Aimbetova, Sultan Yulusov, Inkar Temirgali, Yerzhan Kuldeyev, Zhanar Korganbayeva
      First page: 85
      Abstract: We investigated the potential of tailings generated from chrysotile asbestos fiber production as a source of iron, nonferrous metals, and gold. We proposed the use of granulometric separation and systematically examined different enrichment processes, namely magnetic separation, gravity concentration, and enrichment using a Knelson concentrator, to extract the valuable components. The characterization of the initial tailing samples revealed that it comprises primarily of serpentine, brucite, antigorite, hematite, vustite, sillimanite, and magnesium oxide. Using the suggested enrichment process, we isolated gold, chromite, and nickel-cobalt concentrates as valuable products in addition to magnetite. The new approach exhibited high separation efficiency for iron, nonferrous metals, and gold, allowing their satisfactory extraction.
      Citation: Recycling
      PubDate: 2022-11-17
      DOI: 10.3390/recycling7060085
      Issue No: Vol. 7, No. 6 (2022)
  • Recycling, Vol. 7, Pages 86: Kinetics of Zn–C Battery Leaching with
           Choline Chloride/Urea Natural Deep Eutectic Solvents

    • Authors: Irlanda G. Cruz-Reyes, Jorge A. Mendoza-Pérez, Rosario Ruiz-Guerrero, Dulce Y. Medina-Velázquez, Luis G. Zepeda-Vallejo, Ángel de J. Morales-Ramírez
      First page: 86
      Abstract: A choline chloride/urea natural deep eutectic solvent (ChCl NADES) was prepared via a green chemistry method and used to leach Zn and Mn oxides from conventional Zn–C scrap batteries. FTIR and 1H NMR spectroscopy were used to characterize the NADES. The leaching kinetics of the Zn and Mn oxides was monitored at isothermal conditions (80, 100, 125, and 150 °C) and at two solid/NADES ratios: 3.3 and 10 g dm−3. It was possible to dissolve Zn and Mn oxides under all of tested conditions, reaching more than a 95% recovery for both metals at 150 °C after 90 min, whereas, at 25 °C, it was possible to leach up to 90% of the Zn and 30% of the Mn after 4320 min (72 h). Furthermore, the leaching kinetics was controlled by the boundary layer, coincident with a shrinking core model. According to the Arrhenius plot, the activation energy for Zn ranges from 49.13 to 52.21 kJ mol−1, and that for Mn ranges from 46.97 to 66.77 kJ mol−1.
      Citation: Recycling
      PubDate: 2022-11-18
      DOI: 10.3390/recycling7060086
      Issue No: Vol. 7, No. 6 (2022)
  • Recycling, Vol. 7, Pages 87: Healthcare Waste Management in Nigeria: A

    • Authors: Obiora B. Ezeudu, Tochukwu S. Ezeudu, Uzochukwu C. Ugochukwu, Imokhai Theophilus Tenebe, Agbaji P. Ajogu, Uchenna V. Nwadi, Charles C. Ajaero
      First page: 87
      Abstract: Healthcare waste management has become an important aspect of medical care delivery globally. This is simply because of its hazardous and infectious components that have greater potential for adverse health and environmental impacts. As such, certain guidelines and procedures have been developed by international aid agencies and conventions to guide national governments and local administrations in formulating policies and practices for effective healthcare waste management. In this work, we reviewed the existing literature to appraise the status of healthcare waste management practices in Nigeria. This included generation, segregation, collection, storage, transportation, treatment, and disposal. The current work further reviewed the other essential elements of healthcare waste management, such as policy landscapes, training, awareness, and waste characterization, and discusses challenges and opportunities for effective healthcare waste management in Nigeria. Among the challenges are poor funding, inadequate training, ineffective legislature, and absence of data. However, there are available low-cost technologies that are suitable for the treatment of waste in a developing country like Nigeria. This technology variant offers an opportunity for a circular economy as it can simultaneously achieve energy production, waste management, and other socioeconomic advantages.
      Citation: Recycling
      PubDate: 2022-11-21
      DOI: 10.3390/recycling7060087
      Issue No: Vol. 7, No. 6 (2022)
  • Recycling, Vol. 7, Pages 88: Evaluation of Construction and Demolition
           Waste Management in Kuwait

    • Authors: Mohammed Baqer Hasan Almusawi, Ahmad Tarmizi Bin Abd Karim, Saleem Ethaib
      First page: 88
      Abstract: This research aimed to evaluate Kuwait’s current construction and demolition waste (C&D waste) situation by focusing on C&D waste generation and management issues. This work also investigated the causes and factors affecting C&D waste to understand the actual waste management activities and proposed strategies to minimize the waste generated at the local level. This study estimated C&D waste generation rates based on data collected from five construction projects and two demolition projects in Kuwait. In addition, a questionnaire survey was conducted to evaluate the causes of C&D waste generation. The results showed that the average C&D waste quantities generated by construction activities were 49.5 kg/m2 for public/commercial building projects and 35 kg/m2 for residential projects. At the same time, public/commercial construction, residential construction, and demolition works generated 1.480 ton/m2, 0.0495 ton/m2, and 0.035 ton/m2, respectively. The average composition of C&D waste from the construction sector was 35.4% concrete waste, followed by 19.2% tiles/blocks, and 14.2% metals, with the remainder being other materials. Meanwhile, the demolition waste was composed of 70% concrete and cement waste and 20% metals. The results showed that 54% of the projects disposed of their C&D waste directly in the landfills. The leading causes of C&D waste generation were reworks due to changes in specifications, poor material quality, improper material handling, and improper site management. Strategic C&D waste management practices are necessary for sustainable natural resource management and conservation of the environment.
      Citation: Recycling
      PubDate: 2022-11-24
      DOI: 10.3390/recycling7060088
      Issue No: Vol. 7, No. 6 (2022)
  • Recycling, Vol. 7, Pages 89: Sustainable Bio-Composites Obtained from
           Recycling Post-Industrial PLA and Fillers Derived from Coffee Production

    • Authors: Andrea Saccani, Maurizio Fiorini, Gianfranco Burzotta
      First page: 89
      Abstract: Bio-composites have been formulated by exploiting post-industrial PLA derived from thin film production and silver skin, a by-product of the coffee’s roasting process. The mix design for the compounds exploits the effects of regrading and toughening agents. The mechanical properties of the materials have been investigated as well as the thermal and physical ones. The recycled material mixed with the regrading additive shows good mechanical properties. The filler addition increases the elastic modulus of PLA up to a 20% but decreases the mechanical properties (about 20% on tensile strength), leading to a brittle behavior (minus 35% of impact strength). The use of a toughening agent restores the plastic deformation ability of the matrix.
      Citation: Recycling
      PubDate: 2022-11-30
      DOI: 10.3390/recycling7060089
      Issue No: Vol. 7, No. 6 (2022)
  • Recycling, Vol. 7, Pages 62: Assessment of Public Opposition to
           Construction and Demolition Waste Facilities: A Case Study in Australia

    • Authors: Soheila Ghafoor, Salman Shooshtarian, Tayyab Maqsood, Peter SP Wong
      First page: 62
      Abstract: The purpose of this paper is to investigate the nature of public opposition (PO) to the siting of construction and demolition (C&D) waste management facilities in Australia. A qualitative case study of PO to the development proposal for the Gunnedah waste facility, in the state of New South Wales (NSW), was conducted. The waste facility is promised to process up to 250 kilotons of waste materials, much of which is C&D waste intended for use in road constructions after processing. Using a content analysis approach, the study analysed 86 public submissions that were lodged within the allocated development application exhibition period to systematically analyse the arguments used by the submitters about the establishment of the facility. The case study revealed five broad perceived risk classes to the siting of the Gunnedah waste facility, namely location, environmental, human health, financial and process risks. It was also shown that while not-in-my-back-yard (NIMBY) attitudes may have played a part in the PO to the sitting at the facility, the PO was heavily affected by the poor public participation process. The study outlines key strategies for an effective public participation process that may assist with the management of PO to the siting of C&D waste management facilities in Australia. The study contributes to the theory and practice of effective C&D waste management, enhancing the social acceptance of such facilities toward a more circular economy in the built environment.
      Citation: Recycling
      PubDate: 2022-08-26
      DOI: 10.3390/recycling7050062
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 63: Quantification of Construction Waste in Early
           Design Stages Using Bim-Based Tool

    • Authors: Rocío Quiñones, Carmen Llatas, Maria Victoria Montes, Isidro Cortés
      First page: 63
      Abstract: Construction and demolition waste represents a growing environmental, social, and economic problem, and has become a priority for European and worldwide policies. The early quantification of construction waste is essential for the minimisation of its production and the improvement of waste management. This requires the development of design-based tools that enable a better understanding of the expected waste produced during the construction phase. Building Information Modelling (BIM) methodologies have gained recognition in the Architecture, Engineering, Construction, and Operations (AECO) sector, largely due to their capacity for data simulation, storage, and management during the building design phase. This study presents a software application, called WE-BIM Add-in, to quantify construction waste (CW) while designing the BIM model in Revit. A validated CW quantification model which enables waste types and quantities per building element to be predicted in detail according to the European List of Waste (LoW) is integrated into the Revit workflow. Design alternatives could be effortlessly simulated in real time to assist practitioners in decision-making during the early design stages. Two alternative structural systems of a Spanish residential building were compared: a reinforced concrete structure, Option 1 (O1), and a steel structure, Option 2 (O2). The results were obtained automatically: O2, in addition to reducing 56% of O1′s waste, would have increased the waste recycling rate by 49%; and displayed in Revit, thereby remaining consistent with those of other studies that compare prefabricated systems with in situ systems. This work provides a basis for future research into the automated estimation of construction waste in BIM which could become a useful tool in waste-prevention policies.
      Citation: Recycling
      PubDate: 2022-08-31
      DOI: 10.3390/recycling7050063
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 64: The Current State, Challenges, and
           Opportunities of Recycling Plastics in Western Australia

    • Authors: Ana María Cáceres Ruiz, Atiq Zaman
      First page: 64
      Abstract: In 2018–2019, 85% of discarded plastics were landfilled in Australia. In Western Australia (WA), only 5.6% of plastics were recovered for reprocessing. With several Asian Countries imposing import restrictions, which were the prime destination for recyclables from Australia, the whole scenario for the waste industry has changed. Australia has now adopted export bans for recyclables, including plastics. WA is at a fork in the road; WA needs to rethink its relationship with plastic materials. This study explores how to create local markets for recycled plastics underpinning circular principles. The study examines barriers and drivers to enable markets for recycled plastics in WA through questionnaires, surveys, and interviews with relevant stakeholders. Poor source separation, low and inconsistent plastic waste feedstock, and virgin plastic competition are some of the challenges, while new investments in recycling infrastructure, WA’s take-back scheme for beverage containers and circularity frameworks are drivers. This study concludes that a modulated fee-based product stewardship model focused on product design, along with strategies such as green procurement and landfill management modifications would promote a circular plastic waste economy in WA. This can create markets for secondary recycled plastics, minimize the over-reliance on fossil fuels and prevent plastics from leaking into ecosystems.
      Citation: Recycling
      PubDate: 2022-09-06
      DOI: 10.3390/recycling7050064
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 65: Plastics Crash Course: A Website for Teaching
           Plastics Recycling and Microplastics Prevention through Infographics

    • Authors: Madison R. Reed, Wan-Ting Chen
      First page: 65
      Abstract: Microplastic particles have been found virtually everywhere, including within our food and drinking water. While the implications of microplastics on human health are not fully known, early effects have been seen on marine life and the environment. Studies have shown that microplastics can cause changes in the reproductive habits of marine life by blocking digestive tracts, causing abrasions to the mouth and esophagi of small animals upon ingestion, and altering feeding behavior. While much of the blame for our plastics pollution problem should be shifted to irresponsible manufacturing, we as consumers must make choices to benefit the environment by reducing our use and learning how to effectively recycle plastic waste. The Plastics Crash Course combines visual learning with plastics recycling knowledge to educate the public about why we need plastics and why we should recycle them. Microplastics formation and general guides for plastic recycling were also included in the Plastics Crash Course. Out of 120 participants, 95% responded that they had learned new information. From the pre-survey, participants responded, saying they thought all plastic was the same and that it just varied in density to provide different properties, so they would recycle everything. After reading the infographics on the Plastics Crash Course website, most participants said they learned what plastics can be recycled and what their resin identifying codes mean, how microplastics form, and that there is more than one type of plastic.
      Citation: Recycling
      PubDate: 2022-09-07
      DOI: 10.3390/recycling7050065
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 66: New Terahertz Wave Sorting Technology to
           Improve Plastic Containers and Packaging Waste Recycling in Japan

    • Authors: Jeongsoo Yu, Xiaoyue Liu, Gaku Manago, Tadao Tanabe, Shiori Osanai, Kazuaki Okubo
      First page: 66
      Abstract: Plastic product consumption and disposal are widespread. Given that these products are derived from crude oil, it is critical to reduce their consumption and effectively recycle plastic waste as recycled resources to achieve a low-carbon society. Japan enacted the “Containers and Packaging Recycling Law” in 2000, encouraging the recycling of plastic packaging and containers. However, material recycling of plastic waste has stalled due to recycling costs and technical challenges. This paper examines and evaluates the transition process and operational status of Japan’s recycling policy for plastic containers and packaging, as well as clarifies the limits of resources recycling. The limits and issues of current identification technology are discussed by analyzing the characteristics of plastic marks and detecting the material compositions of waste samples. The paper also discusses a new sorting technology that uses terahertz waves to improve plastic recycling. This analysis revealed that plastic containers are typically made of two or more plastic materials, which makes resources recycling more difficult. Terahertz waves are safer than other high-accuracy sorting technologies currently in use. Thus, material recycling can be expanded by accurately analyzing the composition of plastic waste and introducing sorting devices appropriate for achieving the circular economy with sustainable resource recycling.
      Citation: Recycling
      PubDate: 2022-09-09
      DOI: 10.3390/recycling7050066
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 67: Biohydrometallurgical Recovery of Metals from
           Waste Electronic Equipment: Current Status and Proposed Process

    • Authors: Kundani Magoda, Lukhanyo Mekuto
      First page: 67
      Abstract: Electronic waste (e-waste) is an emerging health and environmental burden due to the toxic substances present within e-wastes. To address this burden, e-wastes contain various base, rare earth and noble metals, which can be recovered from these substances, thus serving as secondary sources of metals. Pyrometallurgical and hydrometallurgical processes have been developed to extract metals from e-waste. However, these techniques are energy-intensive and produce secondary wastes, which will add to the operating costs of the process. However, the biohydrometallurgical approach has been deemed as an eco-friendly, cost-effective, and environmentally friendly process that does not produce large quantities of secondary waste. However, research has focused chiefly on one-stage bioprocesses to recover the metals of interest and majorly on base metals recovery. Hence, this review proposes a two-stage bio-hydrometallurgical process where the first stage will consist of acidophilic iron and sulphur oxidising organisms to extract base metals, followed by the second stage which will consist of cyanide-producing organisms for the solubilisation of rare earth and precious metals. The solid waste residue that is produced from the system can be used in the synthesis of silica nanomaterials, which can be utilised for various applications.
      Citation: Recycling
      PubDate: 2022-09-12
      DOI: 10.3390/recycling7050067
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 68: Comparative Study of Manufacturing NdFeB
           Magnet Wastes Recycling: Oxidative Roasting-Selective Leaching and Whole
           Leaching Routes

    • Authors: Tapany Patcharawit, Woranittha Kritsarikan, Tanongsak Yingnakorn, Sakhob Khumkoa
      First page: 68
      Abstract: This research investigated recycling of manufacturing NdFeB magnet wastes in as-sintered and powder forms which contained high carbon via pyro-hydro metallurgy process. Effects of oxidative roasting on selective leaching of the magnet wastes were the main focus in comparison to recycling via whole leaching without oxidative roasting. The process started from oxidative roasting at 600 °C, sulfuric leaching, drying, roasting at 750 °C for powder and 800 °C for sintered wastes, water leaching, oxalic acid precipitation and calcination at 1000 °C to obtain neodymium oxides. Oxidative roasting was found to reduce carbon and resulted in neodymium and iron oxide formation with a minimum amount of neodymium iron oxide. This provided effective selective leaching of neodymium. For whole leaching, a significant loss of neodymium into leached residue was observed. Oxidative roasting-selective leaching provided significant recovery in the amount of 75.46% while whole leaching resulted in only 31.62 wt.% in the case of sintered waste. The final composition via oxidative roasting-selective leaching consisted of 68.11 wt.% neodymium, 19.83 wt.% praseodymium and 0.31 wt.% iron, while whole leaching resulted in a higher amount of iron at 1.20 wt.%. Similar results were obtained for powder magnet waste.
      Citation: Recycling
      PubDate: 2022-09-19
      DOI: 10.3390/recycling7050068
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 69: Manufacturing of a PET Filament from Recycled
           Material for Material Extrusion (MEX)

    • Authors: Maximilian Bustos Seibert, Gerardo Andres Mazzei Capote, Maximilian Gruber, Wolfram Volk, Tim A. Osswald
      First page: 69
      Abstract: Due to its low cost and easy use, the use of material extrusion (MEX) as an additive manufacturing (AM) technology has increased rapidly in recent years. However, this process mainly involves the processing of new plastics. Combining the MEX process with polyethylene terephthalate (PET), which offers a high potential for mechanical and chemical recyclability, opens up a broad spectrum of reutilization possibilities. Turning used PET bottles into printable filament for MEX is not only a recycling option, but also an attractive upcycling scenario that can lead to the production of complex, functional parts. This work analyzes the process of extruding recycled PET bottle flakes into a filament, taking different extrusion screws and extrusion parameters into account. The filament is subsequently processed with MEX into tensile tests. An accompanying thermal, rheological and mechanical characterization of the recycled resin is performed to offer a comparison to the virgin material and a commercially available glycol modified polyethylene terephthalate (PETG) filament. The results show the importance of adequate drying parameters prior to the extrusion and the sensitivity of the material to moisture, leading to degradation. The recycled material is more prone to degradation and presents lower viscosities. Mechanical tests display a higher tensile strength of the recycled and virgin resin in comparison to the PETG. The extrusion of the used PET into a filament and the subsequent printing with the MEX process offers a viable recycling process for the discarded material.
      Citation: Recycling
      PubDate: 2022-09-20
      DOI: 10.3390/recycling7050069
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 70: Plastic Waste Management through the
           Development of a Low Cost and Light Weight Deep Learning Based Reverse
           Vending Machine

    • Authors: Huma Zia, Muhammad Uzair Jawaid, Hafiza Sundus Fatima, Imtiaz Ul Hassan, Azmat Hussain, Sheryar Shahzad, Muhammad Khurram
      First page: 70
      Abstract: The management of the abundant amount of used plastic bottle waste is a major concern nowadays, because it is a major contributor to landfills and overburdens waste processing facilities. Once disposed of, plastic can take centuries to break down, hence, recycling not only manages the waste efficiently, but it reduces the environmental impact and creates economic opportunities, as well. An incentive-based Reverse Vending machine (RVM) is an effective way to involve the general public in the management of plastic waste. The existing solutions are either very expensive, from a computation and cost perspective, or they lack the robustness and durability necessary for deployment. In this research, we have developed an incentive-based low-cost RVM for the collection, identification, classification, and sorting of used plastic bottles with the addition of a reward-based user application. The developed RVM includes a low-cost computing device running a lightweight image processing algorithm, sensors, camera, and a self-designed mechanical arm. To support the low computing device in the RVM, a lightweight MobileNet model has been trained using transfer learning. A dataset of 10,983 pet bottle images was collected using a camera installed inside the machine for the classification model. The results of the study show that MobileNet achieved 99.2% testing accuracy, which is better than the existing bottle-classification approaches. Moreover, the weight of the developed model was only 12 Mb, which is fourteen and six times less than inceptionV3 and Res-Net (Residual Neural Networks), respectively. Furthermore, the developed RVM costs a fraction of the price, compared to the existing solutions. Two versions of the machine have been deployed at a University for more than 6 months, collecting over 650 kg of plastic waste.
      Citation: Recycling
      PubDate: 2022-09-22
      DOI: 10.3390/recycling7050070
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 71: Design of a Fixed-Bed Column with Vegetal
           Biomass and Its Recycling for Cr (VI) Treatment

    • Authors: Uriel Fernando Carreño Sayago, Yineth Piñeros Castro, Laura Rosa Conde Rivera
      First page: 71
      Abstract: The aim of this work is to design a fixed-bed column with vegetal biomass of Eichhornia crassipes and the process of recycling it for treatment via the adsorption of water loaded with chromium (VI). In the first stage, the relationship between the fixed-bed density and the microparticle density is calculated, giving a model for the design of the fixed bed. Using this model, two systems for the treatment of Cr (VI)-contaminated water were designed and built. The vegetable biomass at three particle diameters of 0.212 mm, 0.30 mm and 0.45 mm was evaluated in the removal of Cr (VI) from water using the designed fixed-bed systems, giving the best removal of Cr (VI) with the lowest size particles and allowing the validation of the proposed model with the Thomas model. The incorporation of iron into the biomass allowed for the treatment of near 2.0 L of polluted solution, removing around 90% of Cr (VI), while it was only possible to treat nearly 1.5 L when using raw biomass, removing around 80% of Cr (VI). The recycling of the biomass was achieved via the elution of Cr (VI) with EDTA, permitting the reuse of the material for more than five treatment cycles.
      Citation: Recycling
      PubDate: 2022-09-24
      DOI: 10.3390/recycling7050071
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 72: Applied Tests to Select the Most Suitable
           Fungal Strain for the Recovery of Critical Raw Materials from Electronic
           Waste Powder

    • Authors: Ester Rosa, Simone Di Piazza, Grazia Cecchi, Michela Mazzoccoli, Micol Zerbini, Anna Maria Cardinale, Mirca Zotti
      First page: 72
      Abstract: Electrical and electronic wastes (WEEEs) are a potential source of raw materials. The main challenge for scientists is to set up a reliable and eco-friendly process to recycle raw materials and precious elements from WEEEs. Today, we know that fungi could play an active role in green technologies aimed at recycling valuable elements. The bioaccumulation mechanism and bioleaching activity of filamentous fungal species have already been exploited fruitfully in extraction processes. However, not all fungal strains possess the same characteristics, and it is crucial to choose the right strains to use. In this work, we show a method to assess the precious elements’ recovery efficiency from WEEE using fungal strains. A CAS agar screening test for siderophore detection was carried out with three strains. The following plate accumulation test performed on a medium added with 120 ppm of electronic waste powder highlighted the differences in accumulation capability, growth rate, and biomass production. Among the elements in tested waste, yttrium, copper, and palladium show the highest bioconcentration factor. The results confirm the biotechnological potential of fungi to recover valuable elements at the bench scale, highlighting the importance of effective screening tests to assess the most efficient strain for each kind of waste.
      Citation: Recycling
      PubDate: 2022-10-05
      DOI: 10.3390/recycling7050072
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 73: Potential Analysis of the Plastics Value
           Chain for Enhanced Recycling Rates: A Case Study in Iceland

    • Authors: Moritz Mager, Ines Traxler, Joerg Fischer, David C. Finger
      First page: 73
      Abstract: In light of the circular economy gaining momentum, plastics recycling is regarded as a key solution to keep materials in the loop. Continuous efforts are needed to achieve the packaging waste recycling targets set by the European Union. Hence, this work evaluates the potential of the Icelandic plastics value chain for enhanced recycling rates. In addition to identifying the main challenges and opportunities, a feasibility study was conducted on the expansion of the deposit-return system to Skyr cups, allowing for closed-loop solutions. Based on the status quo, proposals for the improvement of the current waste and recycling system are made. Insights were acquired by semi-structured interviews with nine key stakeholders in Iceland, representing vital groups that influence the plastics value chain. The obtained answers followed the same trend, pointing out that a circular economy within the boundaries of Iceland is currently not feasible. This is mainly due to the strong dependence on international partners in all parts of the value chain except waste collection. However, major improvements are required to enhance the current waste collection rate of 28%. No conclusive evidence was found to justify the suitability of Skyr cups for the deposit-return system, as the disadvantages outweigh theoretically higher collection and recycling rates. Moreover, the extended producer responsibility scheme implemented with the Icelandic Recycling Fund is a valuable tool to enforce a design for recycling of products, enabling higher recycling rates. Despite one recycler operating in Iceland, Icelandic stakeholders consider sorting and treatment of mixed plastic waste as economically more efficient by collaborating with experts throughout Europe. Therefore, they expect that the current practice of exporting the majority of the domestic waste will prevail. On the contrary, the authors propose a comprehensive waste treatment and recycling scheme within Iceland, which requires a sorting step prior to three possible pathways, being (1) mechanical recycling, (2) alternative fuel, and (3) waste-to-energy. The aim of the proposed scheme is a reduction in greenhouse gas impact of plastics entering the waste stage by an efficient and flexible design of the relevant technologies within Iceland.
      Citation: Recycling
      PubDate: 2022-10-09
      DOI: 10.3390/recycling7050073
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 74: The Utilization of Waste Toner as a Modifier
           in Trinidad Asphalts

    • Authors: Shane Rambarran, Rean Maharaj, Sharona Mohammed, Nadine Sangster
      First page: 74
      Abstract: As more persons are adjusting to home working in light of the COVID-19 pandemic, there has been a significant increase in the use of technology. Trinidad and Tobago, like many other Small Island Developing States, began exploring strategies in the areas of recycling and reuse techniques to mitigate negative environmental impacts from the disposal of waste toners. The reuse of waste toners as a performance enhancer in bituminous materials has successfully been achieved in foreign jurisdictions; however, the lack of research on the utilization of the indigenous Trinidad Lake Asphalt (TLA) and Trinidad Petroleum Bitumen (TPB) has stymied the application of this strategy locally. The influence of four waste toners (A, B, C, and D) on the rheological properties of an unmodified TLA/TPB paving binder was measured using the dynamic shear rheology (DSR) testing technique. The addition of waste toners noted improvements in the rheological parameters of stiffness, elasticity, and viscosity, exhibiting superior temperature susceptibility. Of great interest was the observation at 90 °C, where the modified paving binders containing 5% Toner C and 20% Toner D were elastically superior to the world-renowned TLA. This study demonstrated the potential of utilizing waste toner as a bitumen modifier, providing an innovative, sustainable disposal option.
      Citation: Recycling
      PubDate: 2022-10-13
      DOI: 10.3390/recycling7050074
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 75: Efficient Recovery of Solid Waste Units as
           Substitutes for Raw Materials in Clay Bricks

    • Authors: Ioannis Makrygiannis, Athena Tsetsekou
      First page: 75
      Abstract: The advent of new materials and technologies in building materials has changed the way of building. New lighter materials with easier application methods and improved mechanical behaviors, have become necessary for the market. Moreover, the new environmental policy (2022) aims to transform the waste management into sustainable materials management to ensure the long-term protection and improvement of the environment. For the brick and tile industry, raw materials and the additives that compose the product mixture seem to be a key factor in this direction. Furthermore, every product type (solid or perforated brick) requires different additives to achieve the properties that are postulated by the international standards. For the study, the wide range of additives that were used have been assorted into three (3) categories: the inert materials, the lightweight materials, and the industrial remains. Totally, eight (8) different materials were used as additives into ceramic mass, in different proportions each time. Almost all additives used for this research were pore-forming agents. These burn out almost completely before reaching the full-fire temperature, and do not change the fired body. As a result of additives burnt out, the necessary pore volume is formed in the fired brick body, which, if combined with an appropriate percentage of voids, result in raw density readings. The pore structure is significant as long as the ultimate strength of lightweight bricks is acceptable. In this study, additives between 3 and 25% by weight were added to the clay mixture. The extrusion of specimens in solid form was carried out using the Laboratory’s vacuum press. Firstly, the extrusion of specimens from the original raw material was implemented. Secondly, it was made on the material mixed with the additives mentioned above. A series of experimental activities were followed to determine the variations of the mechanical and physical properties as well as their production procedures (extrusion, drying, and firing). According to five (5) key properties measured in the current study and compared with the mixture without additives, it was found that the variation in thermal conductivity improvement is between -11% and 19%. The bending strength of the fired products showed a decrease from 16% to 55% except for the addition of bauxite residue, which increased the strength by 8%. Bigot drying sensitivity decreased from 11% to 27%. The density in two cases increased from 2% to 7% while in the majority the mixtures with the additives showed a decrease in density from 1% to 14%. Finally, the addition of the necessary water for shaping during extrusion showed a variation from a 10% decreased to a 14% increased water.
      Citation: Recycling
      PubDate: 2022-10-17
      DOI: 10.3390/recycling7050075
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 76: Recycling of Cement–Wood Board
           Production Waste into a Low-Strength Cementitious Binder

    • Authors: Argalis, Sinka, Bajare
      First page: 76
      Abstract: Cement is a widely used building material, with more than 4.4 billion metric tons produced in 2021. Unfortunately, the excessive use of cement raises several environmental issues, one of which is the massive amounts of CO2e produced as a by-product. Using recycled materials in the concrete mix is widely employed to solve this problem. A method for minimizing the use of natural cement by substituting it with secondary cementitious material that consists of wood–cement board manufacturing waste has been studied in this paper. The cement in the waste stream was reactivated by a mechanical treatment method—the use of a planetary mill, allowing it to regain its cementitious properties and be used as a binder. Physical and mineralogical analysis of the binder material was performed using X-ray diffraction (XRD), thermogravimetry/differential thermal analysis (TG/DTA) and Brunauer–Emmett–Teller analysis; granulometry and compressive strength tests were also carried out. The results show that the grinding process did not significantly change the mineralogical composition and the specific surface area; it did, however, affect the compressive strength of the samples prepared by using the reactivated binding material; also, the addition of plasticizer to the mix increased compressive strength by 2.5 times. Samples were cured in high-humidity conditions. The optimal water-to-binder (W/B) ratio was found to be 0.7 because of the wood particles that absorb water in their structure. Compressive strength increased as the grinding time increased.
      Citation: Recycling
      PubDate: 2022-10-17
      DOI: 10.3390/recycling7050076
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 77: Methods of Commercialization and Usage of
           Sosnovsky hogweed Processing

    • Authors: Daria Y. Mironova, Vijayakumar Varadarajan, Ivan V. Timakhovich, Nadezhda V. Barakova, Asemgul A. Tokbaeva, Olga N. Rumiantseva, Elizaveta E. Pomazkova, Igor V. Baranov, Liudmila I. Tishchenko
      First page: 77
      Abstract: Sosnovsky’s hogweed is an invasive species that suppresses natural meadow biocenoses, but at the same time it can be a source of various biological substances (raw materials). Hogweed can be processed to produce cellulose. The obvious advantage of cellulose from Sosnovsky’s hogweed is the unsuitability of the raw material for other uses, i.e., while valuable resources that are now being used to produce cellulose can be saved, the stems of Sosnovsky’s hogweed are waste products obtained because of getting rid of the plant. Despite this, there is an actual problem of including hogweed in the production chain. To solve this problem, business models can be built that are aimed at using the biproducts of processing hogweed. It is important that business models not only reflect the process of producing added value but also can solve the main problem of processing weed plants: the finiteness of the specified resource. Specifically, entrepreneurs starting such a business should not get into a situation where they destroy their only resource. This article is focused on a comparison of business models according to the following criteria: feasibility, profitability, and environmental impact. Business models that involve constructing a processing plant, using mobile laboratories, and industrial symbiosis models are presented. The overall result of this work is a business model that meets the specified criteria. Similar business models can be used for other plants with the possibility of obtaining valuable raw materials. Research shows how Sosnovsky hogweed can be processed into bioethanol or cellulose.
      Citation: Recycling
      PubDate: 2022-10-17
      DOI: 10.3390/recycling7050077
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 78: Green Composites Based on PLA and Cotton
           Fabric Waste: Preparation and Characterization

    • Authors: Narongchai O-Charoen, Piyaporn Kampeerapappun, Khanittha Charoenlarp, Nawadon Petchwattana, Ektinai Jansri
      First page: 78
      Abstract: Textile waste, from both consumption and production, has dramatically increased due to a lack of diversification in its use. Increasing the number of textile alternatives can help to solve these problems. Producing a green composite product is an interesting alternative method. The objectives of this work were to study the preparation and characterization of green composites created from PLA and cotton fabric waste (CFW) and to consider the effect of the CFW content on the composites. The procedure of the research began with CFW pellets preparation; this was subsequently compounded with PLA pellets using a melt-mixing technique with a twin-screw extruder at ratios of 90:10, 80:20, and 70:30 wt% between the PLA and cotton fabric waste, respectively. Then, the testing specimens were produced by compression molding. The experiments demonstrated that an increase in the CFW caused an increase in the viscosity, stiffness, Tg, Tm, and water absorption of the composites. The decomposition temperature of the composites showed a range of 302.41 to 361.22 °C; this decreased when the CFW increased. An increase in the CFW also produced greater and clearer phase separation and roughness on the fracture surface area.
      Citation: Recycling
      PubDate: 2022-10-19
      DOI: 10.3390/recycling7050078
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 79: Recycling Perspectives of Circular Business
           Models: A Review

    • Authors: Md Tasbirul Islam, Usha Iyer-Raniga, Sean Trewick
      First page: 79
      Abstract: The circular business model (CBM) is one of the main building blocks of circular economy (CE), and recycling is one of the main strategies for achieving it. CBM literature is currently evolving, and recycling-oriented discussion has been found in a scattered manner. This review article aims to identify critical components of the recycling-focused business model in CE and evaluate potential business and research opportunities in the area. Data collection was undertaken from the Web of Science (WoS) core collection and ScienceDirect database. Results of the study showed that efficiency of municipal solid waste management, reporting mechanism of recyclers cost of recycled materials, the establishment of a plastic hub, implementation of extended producer responsibility, strategic partnership, incentives, and product design were highlighted as critical requirements for efficient recycling operated business models, especially for waste solar PV panels, e-waste, textile waste, and vehicles and battery sector. It also identified the benefits of using recycled materials in reducing carbon footprint, energy consumption, and achieving low environmental impact. Three-dimensional printing, sensor-based RFID tags, digital twins, additive manufacturing, Industry 4.0, and the Internet of Things (IoT) were found as state-of-the-art technological innovations applied to recycling-oriented circular business models. This article provides critical practical solutions for new business model development and indicates vital future research directions along with a conceptual framework development, which would be helpful for policymakers, business entities, and research academics.
      Citation: Recycling
      PubDate: 2022-10-20
      DOI: 10.3390/recycling7050079
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 80: Assessment of the Energetical and Biological
           Characteristics of Municipal Solid Waste from One of the Largest Landfills
           in Kazakhstan

    • Authors: Arlan Z. Abilmagzhanov, Nikolay S. Ivanov, Oleg S. Kholkin, Iskander E. Adelbaev
      First page: 80
      Abstract: Solid waste management is one of the main problems in large cities. The determination of the quantitative and qualitative composition of municipal solid waste is necessary for proper planning in the processing of such waste. This article presents the results of studies of the morphological composition, physico-chemical parameters and energetical potential of municipal solid waste (MSW) from the landfill of the city of Shymkent. Waste samples were taken from 10 different points of the landfill. The volume–mass parameters of the samples and their average density were determined. The combined waste samples mainly consisted of food waste, paper and cardboard, polymers and plastic, glass, metal, textiles, wood, leather, bones and rubber. Most of the waste, more than 30%, contains plastic products. The moisture of the combustible fraction of the samples is low and varies from 0.3% to 2.3%. The average ash content of the combustible fraction of the samples was determined and its average value is 18.4%. The yield of the volatile substances was determined and the average value per dry state is 78.7%. To determine the energetical potential of municipal solid waste, the gross calorific value was determined and the net calorific value was calculated, the average value of which is 24.15 MJ/kg. This shows the possibility of using solid waste as an energy source.
      Citation: Recycling
      PubDate: 2022-10-20
      DOI: 10.3390/recycling7050080
      Issue No: Vol. 7, No. 5 (2022)
  • Recycling, Vol. 7, Pages 42: Understanding Business Requirements for
           Increasing the Uptake of Recycled Plastic: A Value Chain Perspective

    • Authors: Malou van der Vegt, Evert-Jan Velzing, Martijn Rietbergen, Rhiannon Hunt
      First page: 42
      Abstract: Circularity and recycling are gaining increased attention, yet the amount of recycled plastic applied in new products remains low. To accelerate its uptake by businesses, it will be useful to empirically investigate the barriers, enablers, needs and, ultimately, requirements to increase uptake of recycled plastic feedstock for the production of new plastic products. During the six focus group sessions we conducted, a value chain approach was used to map the factors that actors face regarding the implementation of recycled materials. The identified factors were structured based on three levels: determining whether a certain factor acted as a barrier or enabler, identifying the steps in the value chain that the factor directly affected and the category it could be subdivided into. The results were then further processed by translating the (rather abstract) needs of businesses into (specific) requirements from industry. This study presented eight business requirements that require actions from other actors in the value chain: design for recycling, optimised waste processing, standardisation, material knowledge, showing possibilities, information and education, cooperation, and regulation and government intervention. The main scientific contributions were the value chain perspective and the applied relevance of the findings. Future studies may delve deeper into the individual factors identified.
      Citation: Recycling
      PubDate: 2022-06-29
      DOI: 10.3390/recycling7040042
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 43: Environmental and Economic Comparison of
           Natural and Recycled Aggregates Using LCA

    • Authors: Adriana Dias, Salem Nezami, José Silvestre, Rawaz Kurda, Rui Silva, Isabel Martins, Jorge de Brito
      First page: 43
      Abstract: Recycled aggregates (RAs) have been playing an important role in replacing natural aggregates (NAs) in concrete production, thereby contributing to a reduction in the extraction of natural resources and the promotion of a circular economy. However, it is important to assess the global impacts of this replacement, in both environmental and economic terms. In this study, an overview of the impacts of the production of natural and recycled aggregates is presented, using the life cycle assessment (LCA) methodology. Through this methodology, products with the same function are compared and information about the best solutions is given, considering their environmental and economic impacts. Studies with data collected from specific producers were compared, as well as environmental product declarations (EPDs) and generic databases, regarding the production of natural and recycled, coarse and fine, and rolled and crushed aggregates. This study intends therefore to provide the environmental and economic impact comparison at the global level through LCA from different data sources. According to this literature review, the best and worst environmental results are assigned to lower and higher transport distances, respectively. Regarding EPDs, the lowest environmental impacts are related to recycled coarse aggregates and the highest to natural coarse crushed aggregates. In terms of generic databases, the results are similar, with the lowest impacts associated with natural fine rolled aggregates and the highest to natural coarse crushed aggregates. In what concerns the economic impacts, in general, recycled aggregates are associated with the lowest costs. However, these results are highly dependent on transport distances and costs.
      Citation: Recycling
      PubDate: 2022-06-30
      DOI: 10.3390/recycling7040043
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 44: Improving the Separation of PS and ABS
           Plastics Using Modified Induced Air Flotation with a Mixing Device

    • Authors: Pattarasiri Fagkaew, Nattawin Chawaloesphonsiya, Saret Bun, Pisut Painmanakul
      First page: 44
      Abstract: A dramatic increase in plastic waste has resulted in a strong need to increase plastic recycling accordingly. A selective flotation has been highlighted due to its outstanding efficiency for the separation of mixed plastics with analogous physicochemical characteristics. In this study, the effects of design and operational factors on the bubble’s hydrodynamic and mixing parameters in induced air flotation (IAF) with a mixing device were investigated through a design of experiment method (DOE) analysis for improving the plastic separation efficiency (i.e., PS and ABS). As a result of DOE analysis, the increase in the induced air tube diameter together with the rotational speed could generate a smaller bubble size. This led to the enhancement of the ratio of interfacial area to velocity gradient (a/G), which was interestingly found to be a significant factor affecting plastic recovery apart from the chemical agents. It demonstrates that operating IAF with a mixing device at a greater a/G ratio improved the plastic separation performance. These findings suggest that operating an IAF process with a mixing device at suitable a/G conditions could be a promising technique for separating plastic wastes, which have similar physicochemical characteristics as PS and ABS.
      Citation: Recycling
      PubDate: 2022-07-04
      DOI: 10.3390/recycling7040044
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 45: Recycling of Lead Pastes from Spent

    • Authors: Yongliang Xiong
      First page: 45
      Abstract: Lead–acid batteries are important to modern society because of their wide usage and low cost. The primary source for production of new lead–acid batteries is from recycling spent lead–acid batteries. In spent lead–acid batteries, lead is primarily present as lead pastes. In lead pastes, the dominant component is lead sulfate (PbSO4, mineral name anglesite) and lead oxide sulfate (PbO•PbSO4, mineral name lanarkite), which accounts for more than 60% of lead pastes. In the recycling process for lead–acid batteries, the desulphurization of lead sulfate is the key part to the overall process. In this work, the thermodynamic constraints for desulphurization via the hydrometallurgical route for recycling lead pastes are presented. The thermodynamic constraints are established according to the thermodynamic model that is applicable and important to recycling of lead pastes via hydrometallurgical routes in high ionic strength solutions that are expected to be in industrial processes. The thermodynamic database is based on the Pitzer equations for calculations of activity coefficients of aqueous species. The desulphurization of lead sulfates represented by PbSO4 can be achieved through the following routes. (1) conversion to lead oxalate in oxalate-bearing solutions; (2) conversion to lead monoxide in alkaline solutions; and (3) conversion to lead carbonate in carbonate solutions. Among the above three routes, the conversion to lead oxalate is environmentally friendly and has a strong thermodynamic driving force. Oxalate-bearing solutions such as oxalic acid and potassium oxalate solutions will provide high activities of oxalate that are many orders of magnitude higher than those required for conversion of anglesite or lanarkite to lead oxalate, in accordance with the thermodynamic model established for the oxalate system. An additional advantage of the oxalate conversion route is that no additional reductant is needed to reduce lead dioxide to lead oxide or lead sulfate, as there is a strong thermodynamic force to convert lead dioxide directly to lead oxalate. As lanarkite is an important sulfate-bearing phase in lead pastes, this study evaluates the solubility constant for lanarkite regarding the following reaction, based on the solubility data, PbO•PbSO4 + 2H+ ⇌ 2Pb2+ + SO42− + H2O(l).
      Citation: Recycling
      PubDate: 2022-07-12
      DOI: 10.3390/recycling7040045
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 46: Leading the World: A Review of Household
           Recycling in Wales

    • Authors: Ian D. Williams, Joseph Phillips
      First page: 46
      Abstract: Wales is one of the world leaders in household waste recycling with a steady recent recycling rate of ~65%. The Welsh Assembly Government (WAG) set a statutory target of achieving a 70% recycling rate by 2024/25. We reviewed historical trends in waste management in Wales from 2006 to 2020, with a focus on recycling. Authoritative, official data were obtained from WasteDataFlow, an Internet system for municipal waste data reporting by UK local authorities to government. Data are collected quarterly allowing the generation of time series plots, trendlines and like-for-like comparisons between groupings of various characteristics, such as number of separate kerbside collections, income, political preference, and impact of policy changes. Results showed that the approach taken by the WAG to politically prioritise and encourage participation in household recycling has achieved impressive results that contrast starkly with the recycling performance of other UK countries. In Wales, household waste disposed annually per person via landfill decreased from ~410 kg to <50 kg and household waste recycled increased from to ~150 kg to ~310 kg, with a recent increase in incineration with energy recovery to ~135 kg as infrastructure has come online. Recycling rates show a seasonal variation due to increases in garden waste sent for composting in the summer. There are variations in local authority performance across Wales, mainly caused by variations in the number of separate collections. Co-mingled collections tend to lead to higher contamination of recyclates that are then not able to be sold for recycling. Deprivation, as indicated by differences in income, also influences total waste arisings and recycling rates. A plateau of ~65% recycling rate was reached in 2020, with incineration reaching a rate of >25%. The recycling rate plateaus at exactly the same time as incineration comes on stream. Evidence demonstrates that improvements to recycling rates can become more difficult when incineration becomes available. Whilst further reductions and improvements to recycling in Wales will be more challenging, the WAG’s track record of focused proactive political and policy support shows what can be achieved when there is suitable political will. The WAG has demonstrated that it tends to deliver on its waste-related plans, and it clearly has the best chance of any of the UK’s four countries of achieving its aims.
      Citation: Recycling
      PubDate: 2022-07-18
      DOI: 10.3390/recycling7040046
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 47: Skid Resistance Performance of Asphalt
           Mixtures Containing Recycled Pavement Materials under Simulated Weather

    • Authors: Maria Pomoni, Christina Plati
      First page: 47
      Abstract: One of the challenges of using recycled materials in road structures is to maintain safe and durable pavements. A multitude of research has been conducted over the years on various recycled materials, with a focus on the structural performance of pavements. Another crucial, but almost overlooked, aspect is the pavement’s ability to provide adequate skid resistance for road users under different climatic conditions. With this in mind, the present study aimed to investigate the skid resistance of asphalt mixtures containing two different types of recycled materials under laboratory-simulated weather conditions. Conventional hot-mix asphalt (HMA) and mixtures containing either reclaimed asphalt pavement (RAP) for aggregate replacement or crumb rubber (CR) as a bitumen additive were prepared and tested at different temperatures and different surface conditions (i.e., dry/wet) following a wetting protocol. Skid resistance was measured using a British Pendulum Tester (BPT). The results showed that the recycled mixtures performed similarly to conventional ones in terms of the skid resistance when the temperature was varied and under variable simulated surface conditions too. In some cases, they performed even better than conventional mixtures. Overall, a promising potential is demonstrated towards the use of the investigated recycled materials in asphalt surface courses.
      Citation: Recycling
      PubDate: 2022-07-19
      DOI: 10.3390/recycling7040047
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 48: An Approach for Automated Disassembly of
           Lithium-Ion Battery Packs and High-Quality Recycling Using Computer
           Vision, Labeling, and Material Characterization

    • Authors: Merle Zorn, Christina Ionescu, Domenic Klohs, Konstantin Zähl, Niklas Kisseler, Alexandra Daldrup, Sigrid Hams, Yun Zheng, Christian Offermanns, Sabine Flamme, Christoph Henke, Achim Kampker, Bernd Friedrich
      First page: 48
      Abstract: A large number of battery pack returns from electric vehicles (EV) is expected for the next years, which requires economically efficient disassembly capacities. This cannot be met through purely manual processing and, therefore, needs to be automated. The variance of different battery pack designs in terms of (non-) solvable fitting technology and superstructures complicate this. In order to realize an automated disassembly, a computer vision pipeline is proposed. The approach of instance segmentation and point cloud registration is applied and validated within a demonstrator grasping busbars from the battery pack. To improve the sorting of the battery pack components to achieve high-quality recycling after the disassembly, a labeling system containing the relevant data (e.g., cathode chemistry) about the battery pack is proposed. In addition, the use of sensor-based sorting technologies for peripheral components of the battery pack is evaluated. For this purpose, components such as battery pack and module housings of multiple manufacturers were investigated for their variation in material composition. At the current stage, these components are usually produced as composites, so that, for a high-quality recycling, a pre-treatment may be necessary.
      Citation: Recycling
      PubDate: 2022-07-20
      DOI: 10.3390/recycling7040048
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 49: Stakeholder Assessment on Closing Nutrient
           Cycles through Co-Recycling of Biodegradable Household Kitchen Waste and
           Black Water between Rural and Urban Areas in South India

    • Authors: Veronika Fendel, Martin Kranert, Claudia Maurer, Gabriela Garcés-Sánchez, Jingjing Huang, Girija Ramakrishna
      First page: 49
      Abstract: Agricultural land degradation, urban migration, increasing food demand and waste, and inadequate sanitation systems all affect farmers, local society, and the environment in South India. Joint recycling of biodegradable secondary household resources to close nutrient cycles between urban and rural regions can address all these challenges and thus several SDGs at the same time. Efforts are being made to this end, but many attempts fail. The central research question is, therefore: how can co-recycling concepts be evaluated in this context' For this purpose, composting plants, biogas fermenters, and a high-tech concept to produce plant charcoal, design fertilizer, and biopolymers are considered. The aim of this study is to evaluate the recycling concepts from the stakeholders’ perspective to avoid gaps between theory and practice. Six expert and one focus group interviews on two successful on-site case studies and 15 online expert interviews with thematic actors were qualitatively evaluated and presented in a social network analysis to identify preferences and indicators for the further evaluation of co-recycling concepts. The results show that the focus is on mature technologies such as compost and biogas. High-tech solutions are currently still in rudimentary demand but will play a more important role in the future. To evaluate such concepts, seven key indicators and their measured values were identified and clustered into the categories ecological, social, technical, economic, and connective. The results show that this methodology of close interaction with stakeholders and the evaluation of successful regional case studies minimize the gap between practice and theory, contribute to several goals of the SDGs, and thus enable such concepts to be implemented sustainably.
      Citation: Recycling
      PubDate: 2022-07-20
      DOI: 10.3390/recycling7040049
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 50: Use of a Design of Experiments (DOE) for
           Studying the Substitution of Natural River Sand (NRS) by Gold Mine
           Tailings (GMT) in Concrete Manufacturing

    • Authors: Clarisse Njovu Balegamire, Pierre Jean-Marie Dable, Kouwelton Kone, Bossissi Nkuba
      First page: 50
      Abstract: The extraction of precious minerals leaves behind an important amount of tailings. When stored in nature, these tailings contribute to environmental degradation. To reduce this degradation, tailings are incorporated in construction as substitute to natural materials. The objective of this study was to use a design of experiments (DOE) to reveal how the substitution of natural river sand (NRS) by gold mine tailings (GMT) in concrete manufacturing can be optimally achieved. This DOE considered three constituents: the amounts of NRS/GMT, that of gravel and of cement. The experimental domain was defined within the concrete standards dosage of 350 kg/m3 and 400 kg/m3 as the lower and upper levels, respectively. The smallest compressive strength on standard cubic specimens on the 28th day varied between 11 N/mm2 and 37 N/mm2 following to the experimental domain. The values of the compressive strength of the experiments carried out allowed to acquire the model of the strength with the coefficients of each factor: Strength=23.25−5.86*A+4.56*B−1.96*C−0.56*A*B+1.41*A*C+1.08*B*C+0.71*A*B*C (with A: GMT+NRS; B: cement; C: gravel). The values of the cumulative weight of the coefficients of each factor were 36.7% (A), 64.5% (B) and 76.6% (C). The study also found that a larger dosage of gravel (40 kg) improves the concrete compressive strength when GMT substitutes NRS between 70% and 100% and when 15 kg of cement is used. For a sustainable and better reuse of GMT as construction materials, an economic and environmental study (the leaching of metals) of the concrete based on GMT would be ideal to consider a large scale production.
      Citation: Recycling
      PubDate: 2022-07-26
      DOI: 10.3390/recycling7040050
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 51: A State-of-the-Art Review on the
           Incorporation of Recycled Concrete Aggregates in Geopolymer Concrete

    • Authors: Bahareh Nikmehr, Riyadh Al-Ameri
      First page: 51
      Abstract: Geopolymer concrete (GC) has the potential to incorporate recycled concrete aggregates (RCA) obtained from construction and demolition waste. This research aims to review the current state-of-the-art knowledge of the RCA in GC and identify the existing knowledge gaps for future research direction. This paper highlights the essential factors that impact the GC’s mechanical and durability properties. Moreover, the influence of various percentages of coarse and fine RCA and the pattern of their replacement will be assessed. The effect of aluminosilicate material, alkaline activators, and curing regime also will be evaluated. Besides, the durability-related characteristics of this concrete will be analysed. The impact of exposure to a higher temperature, freeze–thaw cycles, marine environment, and acid and alkali attack will be comprehensively reviewed. A literature review revealed that increasing alumina silicate content, such as slag and metakaolin, and increasing the Na2SiO3/NaOH ratio and alkali-activator-to-binder ratio improve the hardened GC. However, increasing slag and metakaolin content and the Na2SiO3/NaOH ratio has an adverse impact on its workability. Therefore, finding the optimum mix design for using RCA in GC is vital. Moreover, there is a scope for developing a self-compacting GC cured at ambient temperature using RCA.
      Citation: Recycling
      PubDate: 2022-07-27
      DOI: 10.3390/recycling7040051
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 52: Factors Influencing Household Waste
           Separation Behavior: Cases of Russia and Finland

    • Authors: Anna Zaikova, Ivan Deviatkin, Jouni Havukainen, Mika Horttanainen, Thomas Fruergaard Astrup, Minna Saunila, Ari Happonen
      First page: 52
      Abstract: This paper investigates the factors influencing the behavior of individuals in source-separation of municipal solid waste in an immature system for collection of recyclable waste (Saint Petersburg, Russia) and a more mature waste system (selected urban areas, Finland). Online questionnaires were applied to collect data from citizens of Saint Petersburg and the Finnish urban population. The data were examined within an extended theory of planned behavior using structural equation modeling for the identification of factors affecting waste source-separation behavior. The findings indicate that the factors differed significantly in the two waste systems. In Russia, the inconvenience of waste collection limited waste source-separation behavior, while intentions of individuals and information availability had an almost equal positive effect. In Finland, waste source-separation behavior was mostly affected by people’s intentions. Based on the findings, recommendations for the development of recycling practices were made for practitioners in Russia and possibly other early-stage systems for the collection of recyclable waste. Limitations of the study pinpointed the possibilities for future research.
      Citation: Recycling
      PubDate: 2022-07-28
      DOI: 10.3390/recycling7040052
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 53: Unpicking the Gender Gap: Examining
           Socio-Demographic Factors and Repair Resources in Clothing Repair Practice

    • Authors: Rachel H. McQueen, Lisa S. McNeill, Qinglan Huang, Balkrushna Potdar
      First page: 53
      Abstract: Increased fashion consumption spurred by fast fashion has led to excessive textile waste, giving rise to a global crisis as textile waste pollutes land and waterways, while landfill and incineration contribute to global greenhouse gas emissions. Extending a product’s life for as long as possible is a core principle of the circular economy (CE) to ensure that the maximum value of the original product is realized over its lifetime. As such, repair is an essential component of a CE because it supports the preferred waste hierarchy elements of reduce and reuse, with recycling being the last resort in a CE necessary to close resource loops. Consumers are an essential enabler of a CE; therefore, it is critical to understand consumers’ characteristics in the context of behaviors such as repair. The purpose of this study was to examine the role of gender on engagement in clothing repair practices; women have often only been the focus of clothing repair studies. An online survey was conducted to collect responses from Canadian and U.S. consumers (n = 512). Findings showed that self-repair was the most common form of clothing repair, with women being more highly engaged in self-repair practices, increasing with age. Paid repair is the type of repair that has the lowest level of engagement, and there are only negligible differences between the genders. Men utilize unpaid forms of repair more than women. However, among the youngest age group (18–24), both genders are equally likely to have clothing repaired for free. Gender gaps exist, but opportunities for increased utilization in repair can be created to encourage full participation within a CE. In particular, the findings point to the importance of increasing repair activities amongst men and younger consumers.
      Citation: Recycling
      PubDate: 2022-08-05
      DOI: 10.3390/recycling7040053
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 54: Agro-Industrial Wastewater Treatment with

    • Authors: Nuno Jorge, Ana R. Teixeira, Marco S. Lucas, José A. Peres
      First page: 54
      Abstract: The removal of dissolved organic carbon (DOC) and total polyphenols (TPh) from agro-industrial wastewater was evaluated via the application of coagulation–flocculation–decantation (CFD) and Fenton-based processes. For the CFD process, an organic coagulant based on Acacia dealbata Link. leaf powder (LP) was applied. The results showed that the application of the LP at pH 3.0, with an LP:DOC ratio of 0.5:1 (w/w), achieved a high removal of turbidity, total suspended solids (TSS), and volatile suspended solids (VSS) of 84.7, 79.1, and 76.6%, respectively. The CFD sludge was recycled as fertilizer in plant culture (germination index ≥ 80%). Afterwards, the direct application of Fenton-based processes to raw WW was assessed. The Fenton-based processes (UV/Fenton, UV/Fenton-like, and heterogeneous UV/Fenton) showed high energy efficiency and a cost of 1.29, 1.31 and 1.82 €/g/L DOC removal, respectively. The combination of both processes showed the near complete removal of TPh and DOC after 240 min of reaction time, with high energy efficiency. In accordance with the results obtained, the combination of CFD with Fenton-based processes achieves the legal limits for the disposal of water into the environment, thus allowing the water to be recycled for irrigation.
      Citation: Recycling
      PubDate: 2022-08-08
      DOI: 10.3390/recycling7040054
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 55: Experimental and Artificial Neural
           Network-Based Study on the Sorptivity Characteristics of Geopolymer
           Concrete with Recycled Cementitious Materials and Basalt Fibres

    • Authors: Sherin Khadeeja Rahman, Riyadh Al-Ameri
      First page: 55
      Abstract: The environmental concerns regarding the production of the most widely consumed cement construction material have led to the need for developing sustainable alternatives. Using recycled industry waste products such as fly ash and slag via geopolymerisation has led to the development of geopolymer cement—an efficient replacement for ordinary Portland cement (OPC). Adopting geopolymer cement and concrete as a construction material reduces greenhouse gas and promotes the recycling of waste products. This study explores the suitability of a unique geopolymer concrete mix made of recycled cementitious materials including industry waste products such as fly ash, micro fly ash and slag for use in aggressive environments. Sorptivity tests are conducted to assess the durability of concrete and indicate the cementitious material’s ability to transmit water through the capillary forces. This study thus reports on the sorptivity characteristics of a newly developed self-compacting geopolymer concrete and two other fibre geopolymer concrete mixes containing 1% (by weight) of 12 mm- or 30 mm-long basalt fibres. The addition of basalt fibres indicated less water absorption and moisture ingress than the mix without fibres. The study used 18 specimens from three geopolymer concrete mixes, and the results showed that adding fibres improved the durability performance in terms of resistance to moisture ingress. Finally, an artificial neural network model is developed to predict the absorption rates of geopolymer concrete specimens using MATLAB. The prediction models reported excellent agreement between experimental and simulated datasets.
      Citation: Recycling
      PubDate: 2022-08-09
      DOI: 10.3390/recycling7040055
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 56: Special Issue “Feature Papers in
           Recycling 2021”

    • Authors: Francesco Paolo La Mantia, Beatrice Castellani
      First page: 56
      Abstract: Recycling is the collection and conversion process of waste materials into second raw materials [...]
      Citation: Recycling
      PubDate: 2022-08-11
      DOI: 10.3390/recycling7040056
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 57: Reclaiming the Value of Cotton Waste
           Textiles: A New Improved Method to Recycle Cotton Waste Textiles via Acid

    • Authors: Edvin Ruuth, Miguel Sanchis-Sebastiá, Per Tomas Larsson, Anita Teleman, Amparo Jiménez-Quero, Sara Delestig, Viktor Sahlberg, Patricia Salén, Marjorie Sanchez Ortiz, Simran Vadher, Ola Wallberg
      First page: 57
      Abstract: The fashion industry is becoming one of the largest emitters worldwide due to its high consumption of raw materials, its effluents, and the fact that every garment will eventually contribute to the vast amount of waste being incinerated or accumulating in landfills. Although fiber-to-fiber recycling processes are being developed, the mechanical properties of the textile fibers are typically degraded with each such recycle. Thus, tertiary recycling alternatives where textiles are depolymerized to convert them into valuable products are needed to provide end-of-life alternatives and to achieve circularity in the fashion industry. We have developed a method whereby cotton waste textiles are depolymerized to form a glucose solution, using sulfuric acid as the sole catalyst, with a high yield (>70%). The glucose solution produced in this process has a high concentration (>100 g/L), which reduces the purification cost and makes the process industrially relevant. This method can be applied regardless of the quality of the fibers and could therefore process other cellulosic fibers such as viscose. The glucose produced could subsequently be fermented into butanediol or caprolactam, precursors for the production of synthetic textile fibers, thus retaining the value of the waste textiles within the textile value chain.
      Citation: Recycling
      PubDate: 2022-08-12
      DOI: 10.3390/recycling7040057
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 58: Analyzing Polyethylene Terephthalate Bottle
           Waste Technology Using an Analytic Hierarchy Process for Developing
           Countries: A Case Study from Indonesia

    • Authors: Akhmad Amirudin, Chihiro Inoue, Guido Grause
      First page: 58
      Abstract: PET bottle waste is easy to recycle because it is easy to separate, abundant, and competitively priced. Technologies for the treatment of PET bottle waste have been evaluated to date by using life cycle assessment (LCA), but this does not take into account all of the aspects that policymakers consider necessary when selecting an acceptable technology. Aspects such as society, economics, policies, and technical applicability need to be considered along with the environment and resource consumption to complement the LCA results for PET bottle waste. These aspects were selected as criteria for the analytical hierarchy process (AHP), and stakeholders were invited to make a comparison evaluation of the criteria and sub-criteria. Academics were involved to compare the technology options. The results show that society is the highest priority because it is the main actor that ensures the application of the technology, and that job creation is the most important indicator for the selection of the technology in society criteria. After comparing open landfills, sanitary landfills, incineration with energy recovery, pelletizing, glycolysis, and hydrolysis for the utilization of PET bottle waste, this study suggests pelletizing as the acceptable technology for Indonesia because pelletizing is dominant in all the criteria and sub-criteria which support sustainability in waste management. This is the first time that a single plastic fraction that is easy to collect and recycle has been studied with the AHP. The results show that this type of plastic could also be reused in developing countries through mechanical recycling.
      Citation: Recycling
      PubDate: 2022-08-15
      DOI: 10.3390/recycling7040058
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 59: Strength and Microstructure of Coffee
           Silverskin Blended Mortar

    • Authors: Moruf Olalekan Yusuf, Zeyad M. A. Mohammed, Adeshina A. Adewumi, Mutasem Taisir Shaban, Meshrif Omar Meshrif AlBaqawi, Hatim Dafalla Mohamed
      First page: 59
      Abstract: This study pertains to incorporation of coffee silverskin (CSS) in partial replacement for ordinary Portland cement (OPC) in mortar, by investigating its fresh properties (setting and workability), compressive strength (3, 7, 14 and 28-day), absorption and microstructural characteristics. The objectives were to reduce environmental solid wastes and achieve cost efficiency in the use of construction materials. The CSS was expressed as a ratio of total binder (CSS/(OPC + CSS)) and varied from 0 to 5%. The findings revealed that CSS could reduce workability, setting time and early strength. It could also enhance the absorption of the CSS-blended mortar (CBM). The cause of reduction in workability was due to its contribution to the viscosity of the mixture due to the emulsification of the fat component (acetate) and aromatic compounds, as observed in the Fourier Transform Infrared (FTIR) spectroscopy and X-ray diffraction techniques. The presence of these compounds also caused microstructural disintegration that resulted in the lower strength. In addition, the presence of other organic compound in CSS but absent in OPC enhanced microstructural disintegration and porosity in CBM. The 28-day strength of 25 MPa could be achieved in CSS-blended mortar if the CSS/(CSS + OPC) ratios were kept below 3%. The maximum compressive strength of 38.5 MPa was obtained with the optimum CSS content of 1 wt%. The relative density (water) of CSS was 0.345; therefore, it could also be used to produce lightweight concrete. This study promotes the valorization of raw CSS waste as construction material which could be used for subgrade in the construction of road pavement.
      Citation: Recycling
      PubDate: 2022-08-15
      DOI: 10.3390/recycling7040059
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 60: Environmental Effects of Bio-Waste Recycling
           on Industrial Circular Economy and Eco-Sustainability

    • Authors: Sasmoko, Khalid Zaman, Maida Malik, Usama Awan, Wiwik Handayani, Mohd Khata Jabor, Muhammad Asif
      First page: 60
      Abstract: Few prior studies have examined the social and environmental consequences of waste generation and recycling, resulting in a policy gap in the sustainability agenda. The research filled a knowledge vacuum in the literature by investigating the environmental repercussions of different waste generation and recycling processes in the Chinese economy. The study analyzed waste production and recycling statistics over the last 46 years, from 1975 to 2020, and their impact on the nation’s emissions per capita. This study used four primary approaches to determine the links between the examined variables, beginning with the unit root test, which identifies the stationary process of the variables’ underlying processes. Second, the autoregressive distributed lag (ARDL) model was used to produce the variables’ short- and long-run estimates. Third, estimations of Granger causality examined the causal relationships between the variables. Finally, innovation accounting matrices (IAM)were utilized to predict the relationships between variables during the following decade. The unit root estimates imply the mix order of variable integration; hence, it is appropriate to employ ARDL modeling for parameter estimations. The ARDL estimations demonstrate that combustible renewables and waste decrease a nation’s carbon emissions by boosting industrial waste recycling. Despite recycling systems, carbon emissions have escalated to uncontrolled levels owing to the massive production of municipal solid garbage. Sustainable waste management and recycling are vital to reducing carbon emissions. Granger’s estimations of causation imply that combustible renewables and waste and carbon emissions cause industrial and municipal solid waste recycling. Additionally, population growth is responsible for greenhouse gas emissions, biowaste recycling, and industrial waste recycling. Furthermore, this shows the two-way connections between combustible renewables and waste and carbon emissions, implying the need to develop green waste recycling strategies in a nation. The IAM method identified future relationships between variables, which aids policymakers in implementing sustainable waste management practices for a nation. This study concludes that the environmental consequences of waste generation and recycling impede the nation’s circular economy agenda, which can be sustained by knowledge spillovers, chemical reduction in manufacturing, and allocating a certain amount of US dollars to ecological resource conservation.
      Citation: Recycling
      PubDate: 2022-08-15
      DOI: 10.3390/recycling7040060
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 61: Engineering Characterisation of Wearing
           Course Materials Modified with Waste Plastic

    • Authors: Nuha Mashaan
      First page: 61
      Abstract: This review paper shows several sections of bitumen, asphalt mixtures, polymers, and waste plastic in pavement engineering. The paper reviews and evaluates the influence of using waste polymer in improving the rheological and engineering properties of the modified binder and mixtures. Evaluation of properties and design of stone mastic asphalt mixtures are reviewed. Reports and studies had investigated the advantages and importance of using polymer in bitumen modification; however, they yet show a gap in research in terms of the role of waste polymer in improving the durability, aging, and fatigue life in the long term of service.
      Citation: Recycling
      PubDate: 2022-08-18
      DOI: 10.3390/recycling7040061
      Issue No: Vol. 7, No. 4 (2022)
  • Recycling, Vol. 7, Pages 26: Liberation and Separation of Valuable
           Components from LED Modules: Presentation of Two Innovative Approaches

    • Authors: Adam Balinski, Volker Recksiek, Michael Stoll, Christian Christesen, Michael Stelter
      First page: 26
      Abstract: The rapid development of light-emitting-diode (LED) technology is attributed to its superiority over light sources of earlier generations. Although LED lamps, compared to compact fluorescent lamps, are considered less harmful to the environment, there is still no efficient solution to deal with them at the end of their lifecycle. The first part of the study provides a detailed characterisation of LED lamps, focusing on their most interesting component: the LED module. LED packages attached to the module are highly enriched with Ga, In, Pd, Ag, Au, Sr, Y, Ce, Eu, Gd, and Lu, with the content of each element varying greatly depending on the LED technology. In the second part of this research, two new approaches for liberation and concentration of valuable components from LED modules are presented and compared: a chemical route and a thermal route. The chemical treatment leads to a highly selective separation of LED chips and encapsulation. Enrichment factors up to about 125 are achieved, and a concentrate is obtained containing approximately 14 wt% of the aforementioned valuable components. However, the process requires aromatic solvents, which are viewed as toxic. The thermal treatment results in separation of the aluminium heat sink from all other components of the LED module. Enrichment is approximately ten times lower, but the approach is technically feasible.
      Citation: Recycling
      PubDate: 2022-04-19
      DOI: 10.3390/recycling7030026
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 27: Treatment of Scrap Tire for Rubber and Carbon
           Black Recovery

    • Authors: Alaa Sultan Abdulrahman, Fawzi Habeeb Jabrail
      First page: 27
      Abstract: In this study, a chemical dissolution treatment was used to recover rubber and carbon black (CB) from truck tire scrap, with gas oil acting as the solvent and 4-Hydroxy-TEMPO acting as the catalyst for the chemical reactions. Montmorillonite clay was used to separate the rubber solution from the CB and the other non-dissolved tire additives. The recovered rubber and CB were characterized together with the original scrap tire sample by XRD, SEM, BET and thermal analysis, as well as FTIR and 1H NMR spectral analyses. Characterization of the chemical structure of the recovered rubber showed that the main functional groups of styrene−butadiene rubber blend with natural rubber. The thermal behavior and crystalline structure of the recovered rubber, as well as its morphological images, showed that the properties of the rubber sample were acceptable and similar to natural rubber. The recovered CB characterizations showed that the sample after pyrolysis was a highly crystalline nanocomposite structure with a high specific surface area and scattered pores.
      Citation: Recycling
      PubDate: 2022-04-20
      DOI: 10.3390/recycling7030027
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 28: The Physical Characterization and Terminal
           Velocities of Aluminium, Iron and Plastic Bottle Caps in a Water

    • Authors: Alexander A. Nikolaev
      First page: 28
      Abstract: Aluminium, iron and plastic are materials which are extensively used at both industry and individual levels. However, significant amounts of aluminium, iron and plastic end up in the environment. Specifically, bottle caps made of these materials are often thrown away, with or without bottles, and appear among the common plastic debris entering the world’s oceans and beaches. More than 20 million bottle caps and lids have been identified during beach-cleaning campaigns over the last 30 years. To recover bottle caps from the shores, conventional technologies can be used. In this paper, the physical properties of used metal and plastic bottle caps were examined and related to the settling and rising velocities of the caps, as well as their drag coefficients and hydrodynamic modes in water environments, with respect to gravity separation. The sample contained aluminium, iron, high-density polyethylene (HDPE), low-density polyethylene (LDPE), and polypropylene (PP) bottle caps. The findings revealed that the density differences between the bottle caps resulted in the terminal settling velocities of aluminium and iron particles, which were significantly higher than the rising velocities of the plastic caps. The results allowed us to design a flowsheet for bottle cap recovery from beach coasts in order to reduce environmental impact and produce add-on plastic and metal products.
      Citation: Recycling
      PubDate: 2022-04-22
      DOI: 10.3390/recycling7030028
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 29: Analysis of Plastic-Derived Fuel Oil Produced
           from High- and Low-Density Polyethylene

    • Authors: Chandni Joshi Jangid, Kevin M. Miller, Jeffrey R. Seay
      First page: 29
      Abstract: The exponential growth of waste plastic accumulation has had an irreversible and lasting impact on the world. An imminent threat to marine and terrestrial ecosystems of massive proportions, plastic waste accumulation is a global problem that will not only have to be tackled by current generations but for many generations to follow. The scale of current recycling technologies and efforts to reduce consumption by for-profit and non-profit institutions, governments, and consumers will need to be rapidly increased to combat the negative impacts plastic waste has had on the planet since its conception. This is especially the case in areas with limited infrastructure to properly collect, manage, and dispose of plastic waste. Solutions to plastic waste accumulation crisis that are appropriate for the developing world are urgently needed. Conversion of plastic waste to liquid fuel by slow pyrolysis is a technology that is particularly suitable for developing countries due to its ability to convert polyolefin waste plastic into a useful product, thus preventing its eventual accumulation in the ecosystem. However, in developing countries, conversion techniques that do not rely on sophisticated technologies are needed. Since processing time and operating temperature are the simplest variables to control, an analytical study has been conducted to assess how the molecular composition of plastic derived fuel oil (PDFO) is impacted by these parameters. The results of gas chromatography-mass spectrometry (GC-MS) and thermogravimetric analysis (TGA) studies of PDFO from high- and low-density polyethylene plastic waste produced using appropriate technology techniques are presented alongside a comparison with traditional diesel fuel and kerosene. This approach is novel in that it differs from previously conducted research, which has studied the use of catalysts, additives, or single operating temperatures to assess the composition of PDFO. Therefore, this research contribution presents a simplistic and inexpensive approach for tuning PDFO composition in appropriate technology settings.
      Citation: Recycling
      PubDate: 2022-05-07
      DOI: 10.3390/recycling7030029
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 30: Processing of Gypsum Construction and
           Demolition Waste and Properties of Secondary Gypsum Binder

    • Authors: Girts Bumanis, Jelizaveta Zorica, Aleksandrs Korjakins, Diana Bajare
      First page: 30
      Abstract: The waste amount coming from construction and demolition (CDW) has significant volume and potential to provide the backbone of a secondary material bank. Up to now, little attention is paid to waste gypsum recycling from CDW while a shift in global attitude toward waste management brings motivation to use CDW gypsum as secondary raw material. The present research investigates the properties of gypsum binder obtained from secondary raw materials originating from CDW. Three types of drywall boards and cast monolithic gypsum from interior walls, treated in the laboratory, and a gypsum binder was obtained. Comparison has been studied and the most effective solutions regarding CDW treatment are represented. Separation, crushing, and milling were done. DTA/TG, XRD, SEM, and particle size distribution were characterized by CDW gypsum. The heat treatment temperature was selected at 130 °C for 4 or 24 h and 180 °C for 4 h. Consistency, set time, and mechanical properties were characterized. Results indicate that a gypsum binder with a strength up to 3.7 MPa can be obtained. Low strength is associated with fineness of CDW gypsum and a high water/gypsum ratio (from 0.6 to 1.396). Gypsum content in CDW (38 to 92 wt.%) should be considered as an important factor during gypsum CDW recycling.
      Citation: Recycling
      PubDate: 2022-05-17
      DOI: 10.3390/recycling7030030
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 31: Zero Liquid Discharge System for the Tannery
           Industry—An Overview of Sustainable Approaches

    • Authors: Rajamanickam Ricky, Subramanian Shanthakumar, Ganapathy Pattukandan Ganapathy, Fulvia Chiampo
      First page: 31
      Abstract: The tannery industry is characterized by the consumption of a large quantity of water, around 30–40 m3 for processing 1000 kg of hide or skin. This amount becomes wastewater, containing about 300 kg of different chemicals, mainly refractory organic compounds, with high chemical oxygen demand (COD), total dissolved salts (TDS), chromium, and evolution of toxic gases, such as ammonia and sulfides, etc. The remaining tanning chemicals are released as effluent having high resistance against biological degradation, becoming a serious environmental issue. Usually, end-of-pipe treatment is not sufficient to meet the concerns of environmental issues. In terms of cleaner production options, the redesigning of the existing effluent treatment procedures with alternate or additional treatment techniques, which “supports resource recovery with no added chemicals”, is expected to give a sustainable solution for the management of toxic effluent. The Zero Liquid Discharge (ZLD) system serves to ensure zero water emission, as well as treatment facilities by recycling, recovery, and reuse of the treated wastewater using advanced cleanup technology. The international scenario shows the implementation of ZLD thanks to pressure from regulatory agencies. The ZLD system consists of a pre-treatment system with conventional physicochemical treatment, tertiary treatment, softening of the treated effluent, reverse osmosis (RO) treatment for desalination, and thermal evaporation of the saline reject from RO to separate the salts. By adopting this system, water consumption is reduced. Moreover, ZLD also becomes effective in disaster mitigation in areas where the tannery industry is a strong economic actor. With this review, we aim to give an outlook of the current framework.
      Citation: Recycling
      PubDate: 2022-05-24
      DOI: 10.3390/recycling7030031
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 32: Identifying Future Skill Requirements of the
           Job Profiles for a Sustainable European Manufacturing Industry 4.0

    • Authors: Tugce Akyazi, Patricia del Val, Aitor Goti, Aitor Oyarbide
      First page: 32
      Abstract: The exponential growth of digitalisation and the continuous increase in sustainability needs are currently reshaping the European manufacturing industry through its entire value chain. Industrial sectors have undergone significant changes globally in recent years, and they will continue to face this deep transformation. The manufacturing sectors, more specifically, companies, need to develop a relevant strategy that can support their organisation to handle the upcoming future technological developments and sustainability requirements properly. In order to implement the strategy effectively and achieve an adequate digital and green transformation, their main focus should be the development of a multi-skilled workforce. This competent workforce can only be built by foreseeing the changes in the needed skills for the manufacturing industry and then updating the skills of the current workforce accordingly. As an answer to this need, we developed an automated skill database for the manufacturing industry, particularly transversal occupations of this sector related to the industrial symbiosis (IS) and energy efficiency (EE). Differently from the conventional ones, the generated database incorporated not only the current but also the future skill needs for each profile. During the development of the future skills for each occupation in the database, we identified the foreseen skill needs for the manufacturing industry through detailed desk research. Therefore, this paper presents a valuable perspective on the subject. Our work aimed to fill the gap for a database specifically developed for the manufacturing industry, which provides the end-users with data about the new skills requirements resulting from industrial changes and sustainability needs. We believe that companies, education and training institutions and policymakers can make use of the generated database as a complementary tool for developing their training programmes or strategy roadmaps to cover the emerging changes in each individual industrial sector.
      Citation: Recycling
      PubDate: 2022-05-26
      DOI: 10.3390/recycling7030032
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 33: Lithium-Ion Battery Recycling in the Circular
           Economy: A Review

    • Authors: Md Tasbirul Islam, Usha Iyer-Raniga
      First page: 33
      Abstract: Lithium-ion batteries have become a crucial part of the energy supply chain for transportation (in electric vehicles) and renewable energy storage systems. Recycling is considered one of the most effective ways for recovering the materials for spent LIB streams and circulating the material in the critical supply chain. However, few review articles have been published in the research domain of recycling and the circular economy, with most mainly focusing on either recycling methods or the challenges and opportunities in the circular economy for spent LIBs. This paper reviewed 93 articles (66 original research articles and 27 review articles) identified in the Web of Science core collection database. The study showed that publications in the area are increasing exponentially, with many focusing on recycling and recovery-related issues; policy and regulatory affairs received less attention than recycling. Most of the studies were experiments followed by evaluation and planning (as per the categorization made). Pre-treatment processes were widely discussed, which is a critical part of hydrometallurgy and direct physical recycling (DPR). DPR is a promising recycling technique that requires further attention. Some of the issues that require further consideration include a techno-economic assessment of the recycling process, safe reverse logistics, a global EV assessment revealing material recovery potential, and a lifecycle assessment of experiments processes (both in the hydrometallurgical and pyrometallurgical processes). Furthermore, the application of the circular business model and associated stakeholders’ engagement, clear and definitive policy guidelines, extended producer responsibility implications, and material tracking, and identification deserve further focus. This study presents several future research directions that would be useful for academics and policymakers taking necessary steps such as product design, integrated recycling techniques, intra-industry stakeholder cooperation, business model development, techno-economic analysis, and others towards achieving a circular economy in the LIB value chain.
      Citation: Recycling
      PubDate: 2022-05-28
      DOI: 10.3390/recycling7030033
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 34: A Study of the Feasibility of Using Grey
           Sedge Residue to Facilitate Zero Waste Production

    • Authors: Kamonwan Chucheep, Nathaporn Suwanpayak, Naree Phanchindawan
      First page: 34
      Abstract: There is approximately 30% of grey sedge (Lepironia articulata) residue remaining from weaving production that could add value to support zero waste management. Therefore, the aim of this research was to study the feasibility of using a residue of grey sedge or Krajood strips from weaving production to form a value-added product. To obtain preliminary data, Krajood strip residue was examined for its biological and physical properties. In addition, the biological and physical properties of Krajood strip residue in combination with loam soil (KSRL) were examined and compared with the properties of loam soil (LS) itself. The results showed that the total microbe and moisture content of the Krajood strip residue was significantly higher than that of the products made from Krajood strips (KS). The stress value of Krajood strips was higher than the stress values of other samples except for that of a bag made of paper. Identification of bacteria and mold by MALDI Biotyper and DNA sequencing compared with BLAST revealed the presence of the types of soil microbes that benefit plants. KSRL was enriched with larger amounts of the primary elements important for plant growth: nitrogen, phosphorus, and potassium, and the three second tier elements. The pH of KS, LS, and KSRL were 6.40 ± 0.14, 5.87 ± 0.04, and 5.26 ± 0.02, respectively. These results could support the use of this beneficial residue for bioresource sustainability.
      Citation: Recycling
      PubDate: 2022-05-31
      DOI: 10.3390/recycling7030034
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 35: Encouraging Sustainable Use of RAP Materials
           for Pavement Construction in Oman: A Review

    • Authors: Husam Al Dughaishi, Jawad Al Lawati, Munder Bilema, Ali Mohammed Babalghaith, Nuha S. Mashaan, Nur Izzi Md. Yusoff, Abdalrhman Milad
      First page: 35
      Abstract: The Sultanate of Oman has experienced rapid development over the last thirty years and has constructed environmentally friendly and sustainable infrastructure while it continues to find economical alternative resources to achieve the goals of the Oman 2040 vision. The primary concerns are preserving natural resources and reducing the impact of carbon dioxide (CO₂) emissions on the environment. This review aims to encourage the sustainable use of reclaimed asphalt pavement (RAP) materials in pavement construction and focuses primarily on employing RAP materials in new pavement projects. Currently, new construction projects utilise a significant percentage of demolished asphalt pavement to save costs and natural resources. The key issue that arises when mixing RAP into new asphalt mixtures is the effects on the mixtures’ resistance to permanent disfigurements, such as fatigue cracks, that influence asphalt mixture performance. Numerous studies have assessed the impact of using RAP in asphalt mixtures and found that RAP increases the stiffness of asphalt mixtures, and thus improves rutting resistance at high temperatures. Nevertheless, the findings for thermal and fatigue cracking were found to be contradictory. This review will address the primary concerns regarding the use of RAP in asphalt pavements, and aims to encourage highway agencies and academic researchers in the Gulf countries to develop frameworks for the practical usage of RAP in the construction of sustainable pavement systems.
      Citation: Recycling
      PubDate: 2022-06-06
      DOI: 10.3390/recycling7030035
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 36: Does Policy on Plastic Waste Support Higher
           Waste Management Hierarchy Options'

    • Authors: Kunle Ibukun Olatayo, Paul T. Mativenga, Annlizé L. Marnewick
      First page: 36
      Abstract: There is an urgent and growing need to further advance the plastic waste management system globally and in South Africa, due to the increasing impact of plastic waste. This study focused on the adequacy of plastic policies to sustainably manage plastic waste. Policies need to address the plastic material supply systems and the options up the waste hierarchy for them to be effective and support material circularity. The study used qualitative content analysis to assess how the evolution of plastic policies for plastic waste management in South Africa aligned with national plastic material flows and promoted options higher up the waste hierarchy. This was benchmarked with Norway and Germany, which have some of the highest plastic recycling rates. The results showed that the evolution of existing plastic policies for South Africa addresses stages of production, trade and consumption, and recycling. There is no focus on waste generation, collection and sorting. None aligned with the waste hierarchy options of rethink, reduce, reuse, repair, refurbish, remanufacture and repurpose. This policy gap supports the need for broader national plastic policy frameworks that embed a policy drive in the value chain points and promote the priority higher value measures of the waste hierarchy.
      Citation: Recycling
      PubDate: 2022-06-08
      DOI: 10.3390/recycling7030036
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 37: Waste Management for Green Concrete
           Solutions: A Concise Critical Review

    • Authors: Magdalena Osial, Agnieszka Pregowska, Sławomir Wilczewski, Weronika Urbańska, Michael Giersig
      First page: 37
      Abstract: Reinforced concrete based on ordinary Portland cement (OPC) is one of the most commonly used materials in modern buildings. Due to the global growth of the building industry, concrete components have been partially or completely replaced with waste materials that can be used as binders or aggregates. Besides the ecological aspects, modern architecture widely needs materials to make the concrete durable, resisting large loads and various detrimental forces in the environment. This opens the possibilities of managing waste materials and applying them in practice. This paper presents a concise review of the green solutions for ecofriendly materials in the building industry that deal with the practical application of materials commonly treated as waste. The main emphasis was placed on their influence on the properties of the building material, optimal composition of mixtures, and discussion of the advantages and disadvantages of each of the “green” additives. It turned out that some solutions are far from being ecofriendly materials, as they leech and release numerous harmful chemicals into the environment during their presence in concrete. Finally, the paper suggests a research direction for the development of an ecofriendly structural material for a sustainable future.
      Citation: Recycling
      PubDate: 2022-06-10
      DOI: 10.3390/recycling7030037
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 38: An Overview of Packaging Waste Models in Some
           European Countries

    • Authors: Giacomo Di Foggia, Massimo Beccarello
      First page: 38
      Abstract: Efficient packaging waste management systems are essential considering recent revisions of the European legislation on packaging waste management that sets ambitious targets. European rules aim to deal with the increasing quantities of packaging waste, which cause environmental problems. Consequently, it is necessary to identify functional packaging waste management systems to achieve these targets effectively and efficiently. However, given the heterogeneity of the different packaging management systems, policymakers, scholars, and industry operators struggle to have a comparative view. The number of non-harmonized laws in force across countries, autonomous recycling targets, and constant updates are prominent problems that make it difficult to obtain comparable information for research, business, and policymaking. To fill this gap, our research question consists of assigning responsibilities for prevention, collection, recycling, and recovery and an overview of some models at a glance with respect to the general governance and functioning of the system. We base our research on a multiple-case design since more cases are examined using complementary data collection methods, analysis of the previous literature, reports, legislation, and business and institutional websites. Our results provide insights from the following cases: Germany, France, the United Kingdom, the Netherlands, Portugal, Denmark, Spain, and Italy. In addition, policy implications emerge as our insights help overcome barriers in the European market’s development caused by the different rules on packaging management and design serving policymakers that aim to harmonize the management of packaging waste. The paper also contains managerial implications for circular economy business models that can be used by managers who aim to design or upgrade their business models according to both recent legislative upgrades and packaging management systems.
      Citation: Recycling
      PubDate: 2022-06-10
      DOI: 10.3390/recycling7030038
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 39: Properties of Rubberized Concrete Prepared
           from Different Cement Types

    • Authors: Idriss, Gamal
      First page: 39
      Abstract: At present, global waste tire generation considerably exceeds consumption. Moreover, waste rubber tires (WRTs) are a cause of concern, as huge volumes are being discarded and buried, thus causing serious environmental pollution. Rubberized waste concrete (RWC) is a type of environmentally friendly construction material. The main challenge encountered when manufacturing rubberized concrete is the low adhesive properties between the cement paste and rubber particles. This paper demonstrates the effects, through experiments, of using waste tire rubber instead of recycled coarse aggregate (RCA) on two types of cement, i.e., sulfate-resistant cement (SRC) and ordinary Portland cement (OPC), where SRC is a specially blended cement designed to improve concrete performance and workability in the most aggressive environments. All tested samples contained 10% silica fume (SF) and 0.2% fly ash (FA), and the substitution of recycled aggregate content with waste rubber tier (WRT) at different percentages of 100%, 75%, and 50% was evaluated .The research investigated the synergistic effect on the workability and mechanical properties of various cement types with different amounts of rubber aggregate . It was found that the sulfate-resistant (SRC)type can increase the compressive strength than OPC with a percentage of 25% with the same content of WRT at concrete mix. Moreover, ductility and cracking behavior are improved, and it appears that it is also possible to make lightweight rubber aggregate concrete with this type of mixture. Using this type of cement, it is possible to restore satisfactory ductility to the waste tires, thus facilitating a reduction in the formation of potential plastic cracks. Moreover, the indicative compressive strength development for SRC with recycled rubber in concrete positively contributes to a reduction in formed cracks. However, SEM microstructural analyses suggest a higher proportion of C–S–H intermixed with sulfate reaction phases of SRC rubberized mortar than those of OPC; thus, given that crystal growth results in a decreased percentage of air voids rather than decreased internal cracking, it is clearly shown that the average crack width increases in OPC mortar compared with SRC. Finally, t-testing was used as an inferential statistical tool to determine whether there is a sizeable distinction between the properties of the two categories of materials, OPC and SRC, by comparing the mean and standard deviation of the values for compressive and tensile strength.
      Citation: Recycling
      PubDate: 2022-06-12
      DOI: 10.3390/recycling7030039
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 40: Rudimentary Assessment of Waste-to-Wealth of
           Used Tires Crumbs in Thermal Energy Storage

    • Authors: Hussain H. Al-Kayiem, Bilawal A. Bhayo, Elena Magaril, Pavithra Ravi
      First page: 40
      Abstract: Disposing of waste tires is a major environmental and economic issue. Different recycling methods have been studied to account for its re-usage. This project aims to evaluate the possible usage of shredded waste tires in thermal energy storage (TES) applications, whether they are sensible or latent materials. An experimental setup has been developed with seven compartments. Each compartment contains different TES materials, including tire crumbs, paraffin wax, paraffin wax with shredded tires, pebbles, pebbles with shredded tires, concrete, and concrete with shredded tires. In all cases of the mixture, the base materials are 60%vol, and the tire crumbs are 40%vol. The experimental included three locations for temperature measurements in each compartment, solar irradiation, and ambient temperature. The tests were carried out from 9:00 a.m. till 7:00 p.m. and repeated for five days to account for the weather’s daily change. Results revealed that mixed 60%vol pebbles and 40%vol shredded tires have the highest recorded temperature, at 112.5 °C, with a 39.5% increment compared to pure pebbles. The interesting finding is that the added tire crumbs reduced the storage capacity of the paraffin wax, which is latent TES material. At the same time, it increased the storage capacity of the concrete and pebbles, which are sensible TES materials. Adding 40%vol of tire crumbs to the paraffin wax has a negative effect, where the thermal storage capacity is reduced by 43%, and the discharge capacity is reduced by 57%. In contrast, the concrete and the pebbles show enhanced storage capacity. Adding 40%vol of crumbs to the concrete increased the charging capacity by 54% and discharging capacity by 33.7%. The 40%vol added tire crumbs to the pebbles increased its charging capacity by 25% and the discharging capacity by 33%. The rudimentary assessment encourages further investigations on using the wasted tires crumbs for TES. The results reveal the probability of a circular economy using wasted tires with sensible TES for solar-to-thermal energy conversion.
      Citation: Recycling
      PubDate: 2022-06-13
      DOI: 10.3390/recycling7030040
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 41: Assessing Alternative Supporting Organic
           Materials for the Enhancement of Water Reuse in Subsurface Constructed
           Wetlands Receiving Acid Mine Drainage

    • Authors: Martha M. Oberholzer, Paul J. Oberholster, Luyanda L. Ndlela, Anna-Maria Botha, Johannes C. Truter
      First page: 41
      Abstract: Acid mine drainage (AMD) is a global problem with severe consequences for the environment. South Africa’s abandoned mines are a legacy from the country’s economic dependence on the mining sector, with consequent negative impacts on ecosystems. AMD remediation includes active and passive techniques. Constructed wetlands (a passive technique) have lower operational costs but require larger spaces and longer timeframes to achieve the remediation of AMD, and are supported by anaerobic sulphate-reducing bacteria (SRB), which capable of remediating high-sulphate-laden AMD while precipitating dissolved metals from the AMD. Organic substrates supporting these activities are often the limiting factor. When enhancing existing passive AMD remediation technologies, alternative waste material research that may support SRB activity is required to support the circular economy through the reduction in waste products. Chicken feathers show potential as a substrate enhancer, boosting organic carbon availability to SRB, which sustains passive AMD treatment processes by achieving pH elevation, sulphate and metal reductions in AMD water for reuse. Microbial biodiversity is essential to ensure the longevity of passive treatment systems, and chicken feathers are proven to have an association with SRB microbial taxa. However, the longer-term associations between the AMD water parameters, microbial diversity and the selected substrates remain to be further investigated.
      Citation: Recycling
      PubDate: 2022-06-14
      DOI: 10.3390/recycling7030041
      Issue No: Vol. 7, No. 3 (2022)
  • Recycling, Vol. 7, Pages 11: Assessment of Performance and Challenges in
           Use of Commercial Automated Sorting Technology for Plastic Waste

    • Authors: Cesar Lubongo, Paschalis Alexandridis
      First page: 11
      Abstract: Recycling plastic is an important step towards a circular economy. Attaining high-quality recycled plastics requires the separation of plastic waste by type, color, and size prior to reprocessing. Automated technology is key for sorting plastic objects in medium- to high-volume plants. The current state of the art of commercial equipment for sorting plastic as well as challenges faced by Material Recovery Facilities (MRFs) to sort post-consumer plastics are analyzed here. Equipment for sorting plastic recyclables were identified using publicly available information obtained from manufacturers’ websites, press releases, and journal articles. Currently available automated sorting equipment and artificial intelligence (AI)-based sorters are evaluated regarding their functionality, efficiency, types of plastics they can sort, throughput, and accuracy. The information compiled captures the progress made during the ten years since similar reports were published. A survey of MRFs, reclaimers, and brokers in the United States identified methods of sorting used for plastic, sorting efficiency, and current practices and challenges encountered at MRFs in sorting plastic recyclables. The commercial sorting equipment can address some of the challenges that MRFs face. However, sorting of film, multilayered, blended, or mixed-material plastics is problematic, as the equipment is typically designed to sort single-component materials. Accordingly, improvements and/or new solutions are considered necessary.
      Citation: Recycling
      PubDate: 2022-02-23
      DOI: 10.3390/recycling7020011
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 12: Special Issue “The Use of Recycled
           Materials to Promote Pavement Sustainability Performance”

    • Authors: José Neves, Ana Cristina Freire
      First page: 12
      Abstract: Recycling road pavement materials allows for a more sustainable use of raw materials and contributes to creating a circular economy [...]
      Citation: Recycling
      PubDate: 2022-02-23
      DOI: 10.3390/recycling7020012
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 13: Modelling and Simulation of Building Material
           Flows: Assessing the Potential for Concrete Recycling in the German
           Construction Sector

    • Authors: Clemens Mostert, Christian Weber, Stefan Bringezu
      First page: 13
      Abstract: The reuse and recycling of materials can make an important contribution to the conservation of natural resources in the sense of a circular economy. This applies in particular to high quality recycling, supporting the material use of waste and closing product cycles. The construction sector is the most important sector in terms of available volume of materials for recycling. However, the largest share of recycling (RC) materials goes predominantly into road construction and underground engineering. This research developed a dynamic model and used a simulation tool to calculate future building material flows in the German construction sector of residential buildings to explore the medium- and long-term potential for RC concrete. The results show that, by increasing the RC rate of concrete to produce recycled aggregates for concrete (RAC) from currently 1.5% to 48%, up to 179 million tons of sand and gravel could be saved until 2060. If the current maximum secondary input rate of RAC of 45% is increased to 70%, the savings could rise over another 66 million tons. If a secondary input rate of 100% is applied, RAC could completely fulfill the demand for sand and gravel for new residential building in Germany from 2045 onwards. The approval of RC concrete for more concrete strength and exposure classes is required to avoid a surplus of RAC and a rapid exhaustion of landfill capacities in the future.
      Citation: Recycling
      PubDate: 2022-03-01
      DOI: 10.3390/recycling7020013
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 14: Application of Electrodialysis for the
           Selective Lithium Extraction Towards Cobalt, Nickel and Manganese from
           Leach Solutions Containing High Divalent Cations/Li Ratio

    • Authors: Soumaya Gmar, Alexandre Chagnes, Florence Lutin, Laurence Muhr
      First page: 14
      Abstract: The present work aims at investigating the potentialities of implementation of electrodialysis for the recycling of spent lithium-ion batteries. In this work, the use of highly-selective membrane toward lithium(I) in electrodialysis was investigated to recover selectively lithium(I) toward cobalt(II), nickel(II) and manganese(II) by means of monovalent ion-selective membranes. It was shown that the presence of divalent cations in the leach solution is responsible for a significant decrease of the limiting current despite an increase in ionic conductivity. Therefore, monitoring the ionic conductivity was not sufficient to operate electrodialysis under optimal conditions, especially when highly selective membranes were used. Furthermore, it was demonstrated that the current has to be lower than the limiting current to avoid metal hydroxide precipitation into the membrane porosity by monitoring the limiting current over time.
      Citation: Recycling
      PubDate: 2022-03-02
      DOI: 10.3390/recycling7020014
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 15: Factors That Affect Methane Yield Using Raw
           Olive Alperujo (Unhydrolyzed) as Substrate in BMP Assays

    • Authors: Valentina Ortega, Andrés Donoso-Bravo, Rolando Chamy-Maggy, José Luis Campos, Anuska Mosquera-Corral, Marisol Belmonte
      First page: 15
      Abstract: The olive alperujo (OA) corresponds to the solid waste generated in the olive oil extraction process using the two-phase centrifugation method. OA is produced in large quantities (800 kg OA/ton olives processed) and is characterized by its high moisture content, organic matter, and low pH. In Chile, the olive oil industry is recent, and one of its main challenges is to be able to manage OA to reduce the impact caused by its disposal. In this sense, its valorization as biogas by means of anaerobic digestion is an economically attractive option. For this, it is previously necessary to evaluate the biomethane potential (BMP) of the raw OA using batch assays. This study was focused on evaluating the factors that most affect the methane yield (MY) when using OA as substrate in BMP tests. First, a sweep analysis (Plackett–Burman) was applied to determine those factors that, according to the literature, would have an influence on the BMP tests. Among the factors studied, the most significant were preincubation, OA concentration, and agitation level. Subsequently, a 23 factorial experimental design was applied to evaluate the effect of these factors on MY at different levels. Results show that the OA concentration was the most significant factor affecting MY.
      Citation: Recycling
      PubDate: 2022-03-04
      DOI: 10.3390/recycling7020015
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 16: Evaluation of the Performance of Two
           Australian Waste-Plastic-Modified Hot Mix Asphalts

    • Authors: Nuha S. Mashaan, Amin Chegenizadeh, Hamid Nikraz
      First page: 16
      Abstract: The construction of hundreds of kilometres of roads around the world every year results in the consumption of large amounts of raw materials and the depletion of natural resources. In addition, technologically advanced countries such as Australia are currently facing a major issue regarding the waste materials produced daily by their citizens. The disposal of these waste materials is a critical issue faced by municipalities in modern cities. Currently, using waste materials in civil and construction engineering is of great interest to researchers and industry. This study investigates the impact of using waste polyethylene terephthalate to modify asphalt mixtures following Australian design guidelines and criteria. Different types of asphalt are used to investigate and determine the mechanical properties of modified asphalt mixtures. The Marshall stability, Marshall flow, Marshall quotient, and wheel-tracking tests were tested. The Marshall stability, Marshall flow, and MQ of the Marshall test results exhibited significant improvements when using PET in modified SMA and AC mixtures. It can be seen that the 8% PET produced a mixture with the highest stability of 19.78 kN. The lowest rut depth was about 2.08 mm for samples modified with 8% PET.
      Citation: Recycling
      PubDate: 2022-03-04
      DOI: 10.3390/recycling7020016
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 17: Assessment of Belief Constructs to Support an
           Intervention in Municipal Solid Waste Separation at the Source in
           Low–Middle-Income Countries: Observations from the Greater Accra
           Region of Ghana

    • Authors: Kwaku Oduro-Appiah, Abraham Afful, Henrietta Osei-Tutu
      First page: 17
      Abstract: This article uses a modified model of the theory of planned behaviour to assess salient beliefs of household heads towards the separation of municipal solid waste at its source in the Greater Accra Region of Ghana. Structural equation modelling was used to analyse the responses of 598 household heads to a questionnaire in a cross-sectional design. Whilst the default model produced an acceptable fit to the data and explained 37% of the variance in households’ intention to separate waste at its source, the modified model with moral norms as an additional construct fitted the data excellently, explaining 52% of the variance in intention. Moral norms and perceived behavioural control were the predominant latent constructs to influence intentions. Control beliefs related to the availability of waste receptacles, provision of regular waste collection services, and access to knowledge of the separation process had the greatest tendency to facilitate households’ intentions. Pro-environmental interventions designed in a participatory manner to promote moral correctness, responsibility, respect for the environment, and positive affect may empower households to separate waste at its source. This research contributes to the development of a municipal solid waste strategy in the region, and may further support research in waste diversion and the circular economy in other jurisdictions.
      Citation: Recycling
      PubDate: 2022-03-09
      DOI: 10.3390/recycling7020017
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 18: A Comparison on Physical and Rheological
           Properties of Three Different Waste Plastic-Modified Bitumen

    • Authors: Nuha Mashaan, Amin Chegenizadeh, Hamid Nikraz
      First page: 18
      Abstract: This study aims to investigate the effect and the possibility of using waste plastic as a sustainable cost-effective polymer to modify bitumen binders. Different types of waste plastic have been used in this modification, including polyethylene terephthalate (PET), high-density polyethylene (HDPE), and low-density polyethylene (LDPE). The modification targets the physical characteristics, rheological properties, and binders’ resistance to ageing. Both long- and short-term ageing are investigated to determine the durability and ageing resistance of the modified binder using rolling thin film oven tests (RTFOT) and pressure ageing vessels (PAVs). Penetration tests and dynamic shear rheometer (DSR) tests were conducted to investigate and evaluate the complex shear modulus, stiffness, elasticity, and viscous properties. The results show that 2% and 4% of HDPE and LDPE are recommended as ideal contents for good performance, as reflected by the penetration tests before and after ageing. However, higher contents, such as 6% and 8% HDPE and LDPE, are not significant in improving the stiffness, elasticity, and ageing resistance. Therefore, samples of 6–8% HDPE and LDPE are more vulnerable to permanent deformation. Furthermore, using waste PET exhibits obvious improvements in terms of the physical characteristics, rheological properties, stiffness, elasticity, and ageing resistance with up to 8% PET-modified bitumen. Based on the results, the ideal type and content is 6–8% PET waste plastic.
      Citation: Recycling
      PubDate: 2022-03-11
      DOI: 10.3390/recycling7020018
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 19: Life Cycle Assessment of Existing and
           Alternative Options for Municipal Solid Waste Management in Saint
           Petersburg and the Leningrad Region, Russia

    • Authors: Anna Zaikova, Natalia Vinitskaia, Ivan Deviatkin, Jouni Havukainen, Mika Horttanainen
      First page: 19
      Abstract: A waste reform was recently introduced in Russia to divert waste from landfills. To help advance the reform, this paper presents a life cycle assessment of the municipal solid waste management system in Russia’s second largest city—Saint Petersburg—and its neighboring Leningrad region. Five scenarios were evaluated: the current state of the system (S0), its expected post-reform state in 2024 (S1), and its state improved by increased landfill gas collection (S2), by increased waste incineration (S3), and by separate collection of waste (S4). The environmental impact was assessed in terms of climate change, acidification, eutrophication, and abiotic resource depletion (fossil fuels). The results showed an overall reduction in the environmental impact of the waste management system across all impact categories and all scenarios studied. The largest reduction in all impact categories (except abiotic resource depletion) was achieved through source separation of municipal solid waste. Particularly, global warming potential was reduced from 0.328 kg CO2-eq./kg waste generated in S0 to 0.010 kg CO2-eq./kg waste in S4. Regarding abiotic resource depletion potential (fossil fuels), the incineration scenario is the most beneficial, since it reduces the impact by 573%.
      Citation: Recycling
      PubDate: 2022-03-14
      DOI: 10.3390/recycling7020019
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 20: Promising Developments in Bio-Based Products
           as Alternatives to Conventional Plastics to Enable Circular Economy in

    • Authors: Tetiana Shevchenko, Meisam Ranjbari, Zahra Shams Esfandabadi, Yuriy Danko, Kseniia Bliumska-Danko
      First page: 20
      Abstract: Transforming the plastic industry toward producing more sustainable alternatives than conventional plastics, as an essential enabler of the bio-based circular economy (CE), requires reinforcing initiatives to drive solutions from the lab to the market. In this regard, startups and ideation and innovation events can potentially play significant roles in consolidating efforts and investments by academia and industry to foster bio-based and biodegradable plastic-related developments. This study aimed to present the current trends and challenges of bioplastics and bio-based materials as sustainable alternatives for plastics. On this basis, having conducted a systematic literature review, the seminal research themes of the bio-based materials and bioplastics literature were unfolded and discussed. Then, the most recent developments of bio-based sustainable products in Ukraine, as alternatives to petroleum-based plastics, that have gained publicity through local startup programs and hackathons were presented. The findings shed light on the potential of the bio-based sector to facilitate the CE transition through (i) rendering innovative solutions most of which have been less noticed in academia before; (ii) enhancing academic debate and bridging the gap between developers, scholars, and practitioners within the plastic industry toward creating circularity across the supply chain; (iii) identifying the main challenges and future perspectives for further investigations in the future.
      Citation: Recycling
      PubDate: 2022-03-25
      DOI: 10.3390/recycling7020020
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 21: Potential of Alternative Organic Binders in
           Briquetting and Enhancing Residue Recycling in the Steel Industry

    • Authors: Elsayed Mousa, Hesham Ahmed, Daniel Söderström
      First page: 21
      Abstract: Steel production generates various types of residues that cannot be directly recycled in the production process without pre-treatment and agglomeration. In the present study, recipes were designed to develop briquettes in a blast furnace (BF) with the partial replacement of cement with alternative commercial organic binders, including molasses–lime, bitumen, keracoal, carboxymethyl cellulose, and wood tar. The briquettes were produced using a technical-scale vibrating machine and the mechanical strength was evaluated using drop test and standard tumbler index results. The reduction behaviour was investigated by thermogravimetric analysis (TGA) coupled with QMS. A heat and mass balance model (MASMOD) was used to evaluate the potential of developed briquettes to reduce the energy consumption and CO2 emissions from the BF. Although cement was superior in developing mechanical strength, bitumen was the best among the other alternative organic binders and provided sufficient strength to the briquettes at 2.0% addition, which corresponded to 18.2% replacement of total cement. The briquettes containing bitumen possessed a higher reduction rate and lower activation energy compared to cement. The MASMOD calculation demonstrated that the developed briquettes have the potential to provide annual savings of 15,000–45,000 tons of lump coke, 4500–19,500 tons of CO2 emissions, and 5000–20,000 tons of limestone in Swedish BFs.
      Citation: Recycling
      PubDate: 2022-04-01
      DOI: 10.3390/recycling7020021
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 22: Recovery and Use of Recycled Carbon Fibers
           from Composites Based on Phenol-Formaldehyde Resins

    • Authors: Yuliya Kulikova, Natalia Sliusar, Vladimir Korotaev, Olga Babich, Viktoria Larina, Svetlana Ivanova
      First page: 22
      Abstract: The technical feasibility of the recycling of specific polymeric composite materials was evaluated. Two types of carbon composites, both with phenol-formaldehyde resin but with different reinforcement, were studied. It was discovered that the solvolysis with the oxidizing agents used in an acidic environment allowed for the achievement of a high-efficiency fiber extraction. The extracted secondary carbon fibers had a high degree of purity (95–99.5% of resin was removed). Fiber thickness slightly decreased during the process (on average, by 20%). The use of chopped secondary fibers (3–9 mm fiber length) for concrete reinforcement produced a positive effect. Hence, the compressive and bending strength of the concrete blocks were accordingly 1.5% and 16% higher in comparison with the control sample. The use of secondary carbon fabric for the production of composite materials a good result: the effective tensile strength of CFRP samples reinforced with recovered fabric is only lower by 4.5% in comparison with virgin fabric.
      Citation: Recycling
      PubDate: 2022-04-02
      DOI: 10.3390/recycling7020022
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 23: Biofuel Generation from Potato Peel Waste:
           Current State and Prospects

    • Authors: Omojola Awogbemi, Daramy Vandi Von Kallon, Adefemi O. Owoputi
      First page: 23
      Abstract: Growing environmental concerns, increased population, and the need to meet the diversification of the source of global energy have led to increased demand for biofuels. However, the high cost of raw materials for biofuels production has continued to slow down the acceptability, universal accessibility, and affordability of biofuels. The cost of feedstock and catalysts constitutes a major component of the production cost of biofuels. Potato is one of the most commonly consumed food crops among various populations due to its rich nutritional, health, and industrial benefits. In the current study, the application of potato peel waste (PPW) for biofuel production was interrogated. The present state of the conversion of PPW to bioethanol and biogas, through various techniques, to meet the ever-growing demand for renewable fuels was reviewed. To satisfy the escalating demand for biohydrogen for various applications, the prospects for the synthesis of biohydrogen from PPW were proposed. Additionally, there is the potential to convert PPW to low-cost, ecologically friendly, and biodegradable bio-based catalysts to replace commercial catalysts. The information provided in this review will enrich scholarship and open a new vista in the utilization of PPW. More focused investigations are required to unravel more avenues for the utilization of PPW as a low-cost and readily available catalyst and feedstock for biofuel synthesis. The application of PPW for biofuel application will reduce the pump price of biofuels, ensure the appropriate disposal of waste, and contribute towards environmental cleanliness.
      Citation: Recycling
      PubDate: 2022-04-05
      DOI: 10.3390/recycling7020023
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 24: Enzymatic Glucose and Xylose Production from
           Paper Mill Rejects

    • Authors: Joseph Rauzi, Ulrike Tschirner
      First page: 24
      Abstract: Recycled paper fiber rejects have shown potential as a source of waste-to-resource carbohydrates for renewable chemicals production. This study examined three classes of recycled paper fines (old corrugated containers, old newspaper, and mixed office waste) and two industrial papermaking rejects streams from different recycling mills (one mill processes linerboard and the other old corrugated cardboard). The effect of chemical pretreatment using dilute sodium hydroxide, hot water and dilute sulfuric acid on enzymatic glucose and xylose yields was evaluated. Enzymatic hydrolysis results indicated that recycled fiber streams with more old corrugated cardboard have higher potential to produce carbohydrates. The recycled cardboard rejects produced more glucose and xylose per kilogram of rejects than the linerboard rejects under all untreated and pretreated conditions. The highest producing rejects sample was sodium hydroxide pretreated cardboard rejects with 373 g glucose and 61 g xylose produced per kilogram of rejects. However, a simple hot water pretreatment showed similar results, with 335 g glucose and 58 g xylose produced per kilogram of rejects. The hot water pretreatment is recommended due to its comparable yield and lower chemical addition.
      Citation: Recycling
      PubDate: 2022-04-13
      DOI: 10.3390/recycling7020024
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 25: Recycling of Pretreated Polyolefin-Based
           Ocean-Bound Plastic Waste by Incorporating Clay and Rubber

    • Authors: Shawn Martey, Keith Hendren, Nicholas Farfaras, Jesse C. Kelly, Matthew Newsome, Izabela Ciesielska-Wrobel, Margaret J. Sobkowicz, Wan-Ting Chen
      First page: 25
      Abstract: Plastic waste found in oceans has become a major concern because of its impact on marine organisms and human health. There is significant global interest in recycling these materials, but their reclamation, sorting, cleaning, and reprocessing, along with the degradation that occurs in the natural environment, all make it difficult to achieve high quality recycled resins from ocean plastic waste. To mitigate these limitations, various additives including clay and rubber were explored. In this study, we compounded different types of ocean-bound (o-HDPE and o-PP) and virgin polymers (v-LDPE and v-PS) with various additives including a functionalized clay, styrene-multi-block-copolymer (SMB), and ethylene-propylene-based rubber (EPR). Physical observation showed that all blends containing PS were brittle due to the weak interfaces between the polyolefin regions and the PS domains within the polymer blend matrix. Blends containing clay showed rough surfaces and brittleness because of the non-uniform distribution of clay particles in the polymer matrix. To evaluate the properties and compatibility of the blends, characterizations using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and small-amplitude oscillatory shear (SAOS) rheology were carried out. The polymer blend (v-LDPE, o-HDPE, o-PP) containing EPR showed improved elasticity. Incorporating additives such as rubber could improve the mechanical properties of polymer blends for recycling purposes.
      Citation: Recycling
      PubDate: 2022-04-14
      DOI: 10.3390/recycling7020025
      Issue No: Vol. 7, No. 2 (2022)
  • Recycling, Vol. 7, Pages 1: An Empirical Study on the Main Determinants of
           Recycling Plastic Waste in Tunisia

    • Authors: Lamia Ben Amor, Sami Hammami
      First page: 1
      Abstract: Over the past fifteen years, numerous policies for recycling and recovering waste have been implemented throughout the world. Tunisia is among the countries considering recycling as a sustainable development path. This empirical study aimed to investigate and examine the influence of financial determinants measured by the price of waste disposal (PDI), institutional determinants measured by the collection of waste (CW) and the number of drop-off recycling centers, and ordinance and demographic determinants measured by the population density and the recycling rate for plastic as a domestic waste based on a panel of 24 Tunisian governorates over the 2001–2020 period. It is concluded from the empirical findings that all exogenous variables except population density have a significant effect on the recycling rate.
      Citation: Recycling
      PubDate: 2022-01-06
      DOI: 10.3390/recycling7010001
      Issue No: Vol. 7, No. 1 (2022)
  • Recycling, Vol. 7, Pages 2: Baseline Data of Low-Density Polyethylene
           Continuous Pyrolysis for Liquid Fuel Manufacture

    • Authors: Aleksandr Ketov, Vladimir Korotaev, Natalia Sliusar, Vladivir Bosnic, Marina Krasnovskikh, Aleksei Gorbunov
      First page: 2
      Abstract: The recycling of end-of-life plastics is a problem, since small parts can be returned into circulation. The rest is burned, landfilled or recycled into low-quality heating oil by pyrolysis methods. The disadvantages of this method are the need to dispose the formed by-product, pyrolytic carbon, the poor quality of produced liquid fuel and the low productivity of the method associated with the periodicity of the process. In this work, methods of thermogravimetry and chromatography–mass spectrometry (GC-MS) have been used to study the co-pyrolysis products of low-density polyethylene (LDPE) and oxygen-containing substances at the pressures of 4–8 MPa and temperatures of 520–620 °C. Experiments have highlighted the conditions needed for producing of high-quality liquid fuel. Initial data have been prepared for the design of a continuous pyrolysis reactor to dispose polymer waste for the production of bio-oil which would be available to enter the petrochemical products market.
      Citation: Recycling
      PubDate: 2022-01-12
      DOI: 10.3390/recycling7010002
      Issue No: Vol. 7, No. 1 (2022)
  • Recycling, Vol. 7, Pages 3: Acknowledgment to Reviewers of Recycling in

    • Authors: Recycling Editorial Office Recycling Editorial Office
      First page: 3
      Abstract: Rigorous peer-reviews are the basis of high-quality academic publishing [...]
      Citation: Recycling
      PubDate: 2022-01-20
      DOI: 10.3390/recycling7010003
      Issue No: Vol. 7, No. 1 (2022)
  • Recycling, Vol. 7, Pages 4: Critical Evaluation of the Potential of
           Organic Acids for the Environmentally Friendly Recycling of Spent
           Lithium-Ion Batteries

    • Authors: Eva Gerold, Clemens Schinnerl, Helmut Antrekowitsch
      First page: 4
      Abstract: The need to recover valuable metals from spent lithium-ion batteries (LIBs) is undisputed. However, the environment and the climate are also affected by emissions from the recycling processes. Therefore, the call for environmentally friendly recycling methods is currently louder than ever. In the field of hydrometallurgical recovery of metals from spent LIBs, inorganic acids have so far proved to be an effective, but environmentally problematic, leaching agent, since the pollution of wastewater by high salt loads and the emission of toxic gases cannot be avoided. This has recently led to a trend towards the application of organic acids, as these have significantly more environmentally friendly properties. In order to continue this approach, and to improve it even further from an environmental point of view, this work focuses on the utilization of low leaching temperatures in combination with organic acids for the recovery of valuable metals from spent lithium-ion batteries. This can drastically reduce the required energy demand. Furthermore, attention is paid to higher (50–100 g·L−1) solid-liquid ratios, which are indispensable, especially with regard to the economic establishment of the tested process. The experimental verification of the feasibility using citric, oxalic, and formic acid showed the possibility of an efficient recovery of cobalt, nickel, and lithium. In particular, citric acid in combination with hydrogen peroxide as a reducing agent appears to be a suitable and environmentally friendly alternative to classical inorganic acids, even at low process temperatures, for the hydrometallurgical recycling of lithium-ion batteries.
      Citation: Recycling
      PubDate: 2022-01-31
      DOI: 10.3390/recycling7010004
      Issue No: Vol. 7, No. 1 (2022)
  • Recycling, Vol. 7, Pages 5: Effect of Graphite on the Recovery of Valuable
           Metals from Spent Li-Ion Batteries in Baths of Hot Metal and Steel

    • Authors: Elsayed Mousa, Xianfeng Hu, Guozhu Ye
      First page: 5
      Abstract: The recycling of valuable metals from spent lithium-ion batteries (LIBs) is highly important to secure the sustainable production of new LIBs and reduce the dependence on virgin resources. The present paper aims to study the smelting behaviour of black mass (BM) from spent LIBs and investigate the effect of graphite on metal recovery in a carbon-saturated hot metal bath and in a low-carbon steel bath. The smelting trials of BM were conducted in a technical scale (150 kg) induction furnace using hot metal and steel scrap at operating temperatures in the range of 1278–1438 °C and 1470–1610 °C, respectively. Two grades of BM were applied in the current study; high-Ni BM and high-Co BM. Parts of both grades of the BM were briquettes to enhance the direct reduction of metal oxides with embedded graphite and to reduce the dust generation during loading into the furnace. The briquette BM was charged to carbon-saturated hot metal bath while the other part of the BM was subjected to de-coking in a muffle furnace in an oxidising atmosphere to remove graphite (37–39%) and to concentrate the valuable metals in the BM. The de-coked BM was loaded directly, without the need for the briquette, to the low-carbon steel bath. The results indicated that smelting of the de-coked BM in a steel bath is more efficient in metal recovery than the smelting of the corresponding briquette BM in a molten hot metal bath. The highest recovery rate of Co, Ni and Cu (98–99%) was obtained by smelting de-coked high-Co BM in a low-carbon molten steel bath, while the lowest recovery rate (38–55%) was obtained by smelting the briquette high-Ni BM in the carbon-saturated hot metal bath.
      Citation: Recycling
      PubDate: 2022-02-03
      DOI: 10.3390/recycling7010005
      Issue No: Vol. 7, No. 1 (2022)
  • Recycling, Vol. 7, Pages 6: Embodied Energy in Pyrolysis and Solvolysis
           Approaches to Recycling for Carbon Fiber-Epoxy Reinforced Composite Waste

    • Authors: Komal Kooduvalli, John Unser, Soydan Ozcan, Uday K. Vaidya
      First page: 6
      Abstract: Carbon fiber composites are increasingly used in aerospace, motorcycles, sporting, and high-performance vehicles, and their end of life recycling is of growing interest. This study deals with the life cycle assessment (LCA) of carbon fiber reinforced plastics (CFRP) waste streams. The embodied energy (EE) of recycling CFRP via two viable methods—i.e., pyrolysis and solvolysis—is studied. Both pyrolysis and solvolysis were studied for EE with different variants. Alongside fiber recovery from CFRP, the pyrolysis process calculations consider energy recovery from syngas and oil produced within the system. For pyrolysis, electric furnace and natural gas were primarily considered. For solvolysis, different solvent scenarios were considered, including (a) deionized water, (b) water and potassium hydroxide, (c) acetone and water, and (d) water with acetic acid and potassium hydroxide. Energy reduction from one generation to the next has also been highlighted. The EE for recycling CFRP is quantified and discussed for these scenarios in this paper.
      Citation: Recycling
      PubDate: 2022-02-14
      DOI: 10.3390/recycling7010006
      Issue No: Vol. 7, No. 1 (2022)
  • Recycling, Vol. 7, Pages 7: Energy Potential Assessment of Excavated
           Landfill Material: A Case Study of the Perm Region, Russia

    • Authors: Iuliia Shcherbinina, Stepan Polygalov, Galina Ilinykh, Vladimir Korotaev, Natalia Sliusar, Ivana Mihajlovic, Nemanja Stanisavljevic
      First page: 7
      Abstract: The paper presents results of field and laboratory studies of thermal characteristics to excavated landfill waste in Perm region, Russia. The peculiarity of the study includes the following aspects: waste composition with a high share of polymers, the climatic conditions of the territory and the lack of engineering infrastructure at the waste disposal facility. When determining the waste composition and thermal properties of waste, it is proposed to include a stage of removal of contamination from landfilled waste fraction, since their share of contamination can reach up to 33%. This stage will allow researchers to adjust the net calorific value of the excavated waste without overestimation, which may affect decision-making when implementing waste management technology. Among combustible components with the highest moisture content are waste paper (69.1%) and diapers (65.8%), whereas wood (11.2%), PET bottles (3.1%) and other 3D plastics (13.4%) have rather low ash content on a dry basis. Calculation of thermal properties and analysis of the energy potential of the waste samples was conducted based on the obtained data. The calorific value of the individual components and excavated waste depends not only on the moisture and ash content of the individual components, but also on the presence of contaminants. The average net calorific value of the excavated waste is 4.9 MJ/kg, and for the separate mixture of combustible components, it is 7.5 MJ/kg at a moisture content of 44%. Excavated landfill waste can be regarded as a resource for the manufacture of secondary fuel only after pretreatment that includes at least sorting and drying. The results of this study may be useful in developing technologies needed to eliminate old MSW dumps and old landfills, for the development of the concept of circular economy and prevention of environmental degradation problems.
      Citation: Recycling
      PubDate: 2022-02-15
      DOI: 10.3390/recycling7010007
      Issue No: Vol. 7, No. 1 (2022)
  • Recycling, Vol. 7, Pages 8: Physicochemical and Biological Contribution of
           Native Macrophytes in the Constructed Wetlands to Treat Municipal
           Wastewater: A Pilot-Scale Experiment in a Sub-Tropical Climate Region

    • Authors: Tofeeq Aalam, Carlos Alberto Arias, Nadeem Khalil
      First page: 8
      Abstract: In this study, the physicochemical and biological contributions of different macrophytes in horizontal sub-surface flow constructed wetlands (HSSF-CWs) to treat low-strength municipal wastewater operated at high hydraulic loads under a sub-tropical climatic region is investigated. Out of the four identical beds, three were planted with locally available macrophytes (P. australis, Sagittaria, and Iris), whereas one bed was kept as a control. The beds were filled with media and operated in parallel continuously for eight months, with increasing the surface loading rate (SLR) from 0.19 to 2.78 m day−1. The results indicate that the planted beds performed significantly (p < 0.01) better to remove TSS (70% to 78%), BOD5 (66% to 77%), COD (59% to 75%), NO3-N (56% to 64%), NH4-N (41% to 69%), TN (36% to 41%), and TP (44% to 61%) as compared to the unplanted bed for the same parameters (48%, 39%, 40%, 33%, 18%, 20%, and 29%, respectively). The presence of macrophytes in HSSF-CWs was found to be highly significant. The average relative growth rate (RGR) was observed in the order of P. australis (0.0086 day−1) > Sagittaria (0.0061 day−1) > Iris (0.0059 day−1). When compared to the performances of the species used, Sagittaria and P. australis produced better results than Iris. The investigations on biomass showed that Sagittaria yielded higher production, followed by P. australis and Iris. The proportions of uptake by the macrophytes were found to be 9.3%, 6.3%, and 3.9% of mass N removal, and 7.6%, 5.1%, and 4.4% of mass p removal in Sagittaria, P. australis, and Iris, respectively. This study contributes to the effective response to the environment, which validates a major role of macrophytes and their disparate response to pollutant removal processes by different species from municipal wastewater through HSSF-CWs.
      Citation: Recycling
      PubDate: 2022-02-17
      DOI: 10.3390/recycling7010008
      Issue No: Vol. 7, No. 1 (2022)
  • Recycling, Vol. 7, Pages 9: Intelligent and Real-Time Detection and
           Classification Algorithm for Recycled Materials Using Convolutional Neural

    • Authors: Dimitris Ziouzios, Nikolaos Baras, Vasileios Balafas, Minas Dasygenis, Adam Stimoniaris
      First page: 9
      Abstract: In recent years, the production of municipal solid waste has constantly been increasing. Recycling is becoming more and more important, as it is the only way that we can have a clean and sustainable environment. Recycling, however, is a process that is not fully automated; large volumes of waste materials need to be processed manually. New and novel techniques have to be implemented in order to manage the increased volume of waste materials at recycling factories. In this paper, we propose a novel methodology that can identify common waste materials as they are being processed on a moving belt in waste collection facilities. An efficient waste material detection and classification system is proposed, which can be used in real integrated solid waste management systems. This system is based on a convolutional neural network and is trained using a custom dataset of images, taken on site from actual moving belts in waste collection facilities. The experimental results indicate that the proposed system can outperform existing algorithms found in the literature in real-world conditions, with 92.43% accuracy.
      Citation: Recycling
      PubDate: 2022-02-18
      DOI: 10.3390/recycling7010009
      Issue No: Vol. 7, No. 1 (2022)
  • Recycling, Vol. 7, Pages 10: Evaluation of Vermicompost Produced by Using
           Post-Consumer Cotton Textile as Carbon Source

    • Authors: Vijaypal Singh, Jordan Wyatt, Ali Zoungrana, Qiuyan Yuan
      First page: 10
      Abstract: A large amount of textile waste is generated every year around the globe. The textile product made from natural fibers might be vermicomposted and used as fertilizer. The present study aimed to research an integrated system of pre-composting (pathogen kill) and vermicomposting with various levels of post-consumer cotton waste to determine if this addition has any effects on the composting process. A vermicompost bin was constructed and filled with feedstocks mixed with post-consumer cotton textile waste at a 25:1 C:N ratio, and operated for three months at approximately 70% moisture content, with four composting trials with 0 g (control), 100 g, 200 g, and 300 g of textile waste. The pre-composting stage reached a temperature ranging from 40 °C to 50 °C, able to neutralize the pathogens. All four trials resulted in final compost with C: N ratios around 14, proving that post-consumer cotton textile waste did not affect the vermicomposting process, and was successfully used as a carbon source by worms to produce a healthy and mature compost. This indicates a sustainable option for the recovery of textile waste that is being decomposed in landfills.
      Citation: Recycling
      PubDate: 2022-02-21
      DOI: 10.3390/recycling7010010
      Issue No: Vol. 7, No. 1 (2022)
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762

Your IP address:
Home (Search)
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-