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Clean Technologies and Environmental Policy
Journal Prestige (SJR): 0.648  Citation Impact (citeScore): 2 Number of Followers: 5  Hybrid journal (It can contain Open Access articles)ISSN (Print) 1618-9558 - ISSN (Online) 1618-954X Published by Springer-Verlag  [2658 journals]
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- Greenness of things
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PubDate: 2021-11-01
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- Methane oxidation biosystem in landfill fugitive emissions using
conventional cover soil and compost as alternative substrate—a field
study-
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Abstract: Landfill is an important anthropogenic source of greenhouse gases (GHG). Aiming at methane mitigation through the use of a cover layer in the form of fugitive emissions, this study investigated the methane passive bio-oxidation in a Brazilian landfill in biofilters under two conditions: control column (packing material using only landfill cover soil with ≅ 0.8% organic matter) and enriched column (packing material using 45 cm landfill cover soil and 15 cm mixture of cover soil plus compost with ≅ 6% organic matter). Biogas was collected from a vertical drain pipe of a four-year-old cell and injected into the base of the columns with a high inlet loading (1000 gCH4.m−2.d−1) in upward flow mode. Ten campaigns were carried out for six months in order to determine the efficiency of the methane oxidation in each column. Soil temperature, moisture and nutrients content in both filter beds were also determined. The oxidation global efficiencies were higher in the enriched column throughout all campaigns, with ≈71 and ≈95% for the control and enriched columns, respectively, demonstrating that this technology can be applied even in landfills where there is no energy recovery from biogas (as in most landfills in developing countries). Our study demonstrated that the use of substrates with high organic matter content and low cost in landfill cover layers might present high efficacy in the reduction in methane fugitive emissions. Even operating in field-scale conditions, the results of this study were comparable to those obtained with biofilters on laboratory-scale (under controlled operational conditions). Graphic abstract
PubDate: 2021-11-01
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- Techno-economic assessment of common reed and sewage sludge
co-fermentation improved by vapothermal pre-treatment-
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Abstract: This study examines whether vapothermal pre-treatment is technically feasible and brings economic advantages for a subsequent anaerobic co-fermentation of reeds together with sewage sludge. This is illustrated by the example of remote sites located close to constructed wetlands in the Persian Gulf states. Thus, eight different biogas plant configurations with an installed electric power between 75 and 450 kW, each with and without vapothermal pre-treatment, are investigated in detail related to technical and economic figures. Within the technical assessment, suitable plant components are chosen and overall plant layouts are designed and dimensioned. Furthermore, the requirements on the substrate by means of quantity, pre-treatment and storage capacities are investigated. Based on this, an economic evaluation following the annuity method is performed in order to calculate the respective electricity production costs. The results show that the thermal energy required for vapothermal pre-treatment can be obtained completely from the residual heat of the combined heat and power unit used in each case. Additionally, the specific electricity production costs can be reduced by a vapothermal pre-treatment up to 7 % related to the systems without pre-treatment. Furthermore, a comparison shows that vapothermal pre-treatment can compete with other pre-treatment methods such as steam explosion and hydrothermal pre-treatment for plants with higher installed electric capacity. In addition, it is shown that the considered cases can compete with the production of electricity using diesel as a fuel at a fuel equivalent price of 1.00 € Graphic abstract
PubDate: 2021-11-01
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- Enhancing methane production by anaerobic co-digestion of extruded organic
wastes from slaughterhouse and vegetable market in batch and continuous
processes-
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Abstract: The organic wastes generated from centralized wholesale markets from urban centres are predominantly disposed in dumpsites/landfills. Although anaerobic digestion (AD) of wastes is a promising option for producing bio-fuel, the key barrier is the limitation in the waste conversion efficiency that demands the need for the organic waste pretreatment. Hence, the extrusion pre-treatment of wastes prior to AD of slaughterhouse wastes (ESHW) with mixed vegetable, fruit and flower market wastes (EVMW), from a centralized-wholesale market in an urban area, was studied in batch and continuous AD processes. Batch experiments were carried out in mono- and co-digestion modes of extruded wastes. The results of the batch study revealed maximum specific methane yield of 354.9 mLN/g oDM during anaerobic co-digestion of extruded slaughterhouse wastes with mixed vegetable, fruit and flower market wastes in 1:3 proportion (ESHW/EVMW). Based on these results, lab-scale continuous reactor study (15 L) at varying organic loading rates (OLR) was carried out and the maximum biogas yield of 618.5 mLN/g oDM with a methane content of 62.6% and energy potential of 12.2 MJ/kg DM was obtained for extruded wastes at an OLR of 2.5 g oDM/L/d (E) when compared with non-extruded wastes that showed biogas potential of 503.7 mLN/g oDM (with energy potential of 10.2 MJ/kg DM). The outcome of the study revealed that extrusion pretreatment along with anaerobic co-digestion resulted in an increase in the biogas production therein showing enhancement in green energy production during anaerobic co-treatment of centralized wholesale market and slaughterhouse wastes in urban centres. Graphic
PubDate: 2021-11-01
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- The environmental and energy policies to enable sustainable consumption
and production in the Gulf Cooperation Council countries-
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Abstract: Sustainable consumption and production mean that economic development should satisfy the needs of the current population without jeopardizing the lives of future generations. Relying on the hydrocarbon sector generates a significant trade-off between economic development and the environment. The GCC governments have an essential role in this process and can affect the outcomes. The policies that have been implemented in the GCC countries to protect the environment and empower sustainable consumption and production were explored and identified. Moreover, the success of these policies in achieving their goals was assessed. The analytical approach and utilizing the previous studies’ findings were used by the current study. This study finds that the institutional actions of the Gulf countries are not enough to generate sustainable consumption and production. These countries remain strongly affected by the hydrocarbon sector, and the diversification achievements are weak. Further, the energy price reforms have many problems as a tool to enhance sustainable consumption and production. Additionally, these countries work under the concept of entrepreneurial state capitalist. The government controls all the sectors, including the private sector, to secure the regime. The policy implication of the current paper is that the GCC countries should recover the process of diversifying the economy, enhancing the movements toward the free market economy, and adopting an efficient energy-environmental policy by enhancing more concrete actions toward new technologies. It includes shifting to renewable energy, i.e., solar and wind. Graphic abstract
PubDate: 2021-11-01
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- Real-time optimization of plug-in hybrid electric vehicles based on
Pontryagin’s minimum principle-
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Abstract: Battery aging can greatly reduce the energy efficiency of plug-in hybrid electric vehicles (PHEVs). This paper presents a novel real-time energy management strategy (EMS) for PHEVs, aiming at integrating the fuel economy and battery life optimization. While most existing EMSs consider constant battery temperature, this paper includes the temperature variation into the problem since its effect on battery aging is significant. The optimal offline solutions are obtained by dynamic programming (DP) and Pontryagin’s minimum principle (PMP). The results demonstrate that the battery life is extended by making a trade-off between fuel economy and battery aging. Then, a real-time EMS is suggested based on PMP since it is an instantaneous optimization approach. Contrary to the real-time EMSs with a pre-determined costate, a real-time tuning rule for costate is developed, making the strategy adaptable to the uncertainties in traffic conditions. Finally, the suggested method’s effectiveness in lowering the fuel consumption and the battery’s degradation rate is shown through simulations over multiple real-time driving cycles. The proposed method’s simulation results are compared with those of DP, PMP, and the charge depleting–charge sustaining (CD-CS), which is a widely investigated real-time approach. The results indicate that the proposed real-time EMS outperforms the CD-CS, and it has close matching to globally optimal solutions obtained by DP. Graphical abstract
PubDate: 2021-11-01
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- Sustainable supply chain management in construction industry: a Turkish
case-
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Abstract: In the construction industry, social, environmental and economic concerns are increasing in recent years. Sustainability approach is gaining wide interest to solve these concerns. Sustainable supply chain management ensures environmentally and socially pleasant practices, and provides economic gains. We propose a sustainable supply chain management model for the construction industry in Turkey context, which considers all levels of construction process. The proposed model is based on the life cycle assessment of buildings and employs triple bottom line sustainability dimensions—environmental, social and economical. We utilize the analytic network process methodology to evaluate the sustainability level of construction sustainable supply chain management in Turkey by employing the principles of the green buildings performance rating system (LEED). The contribution that lies in this paper provides the importance of sustainable supply chain management elements in construction, reasons for insufficient sustainability and a framework to improve sustainability integration. Graphic abstract
PubDate: 2021-11-01
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- Managing a sustainable integrated inventory model for imperfect production
process with type one and type two errors-
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Abstract: Unlike previous research, this study develops an integrated inventory model for controllable lead time with defective items, errors in inspection, and variable lead time considering sustainability. The research investigates the effect of controlling lead time and capital investment in the setup cost. We assume that the buyer receives a lot size that may contain some defective items with a known defective probability. The buyer’s inspector conducts a 100% quality inspection and may incorrectly classify a non-defective item as a defective item (type one (I) error) or incorrectly classify a defective item as a non-defective item (type two (II) error). The mathematical inventory model considering carbon emission cost is developed, and the solution procedure is designed using the heuristic algorithm to derive the optimal or near optimal solution. Finally, numerical examples and sensitivity analysis are given to illustrate the results. The results show that the defective rate, and type I type II inspection errors, have a significant impact on the shipment lot. This leads to the changes in the total cost, lead time, and the carbon emissions. Our study provides cost savings of 4.39% and carbon emission savings of 28.44%. Graphic abstract
PubDate: 2021-11-01
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- Clean treatment of rejected brine by zero liquid discharge thermal
desalination in Persian Gulf countries-
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Abstract: In this study, four zero liquid discharge thermal desalination processes were technoeconomically investigated to select the most efficient and economic process for the treatment of the brine rejected from desalination units. These processes were (1) evaporation/crystallization, (2) evaporation/spray drying, (3) membrane distillation/crystallization, and (4) membrane distillation/spray drying. To harmonize the economic assessment conditions in this technoeconomic study, the feed concentration and feed flow rate of all processes were considered to be 80,000 ppm and 1500 m3/day, respectively. The results showed that the specific water production costs for Processes 1–4 were 8.1, 22.1, 8.4, and 20.7 $/m3, respectively. Therefore, the produced water from Processes 1 and 3 had the lowest specific production cost. In addition, these processes had the lowest total fixed capital investment. On the other hand, although the specific production cost and the equivalent thermal gained output ratio of Processes 1 and 3 were almost the same, Process 1 can produce demineralized water. Therefore, Process 1 was considered as the most economic option due to the high economic value of demineralized water. Graphic abstract
PubDate: 2021-11-01
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- Carbon footprint in Higher Education Institutions: a literature review and
prospects for future research-
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Abstract: Higher Education Institutions (HEI) or universities, as organisations engaged in education, research and community services, play an important role in promoting sustainable development. Therefore, they are increasingly linked to the initiative of calculating their carbon footprint (CF), which is a tool to assess sustainability from the perspective of greenhouse gas (GHG) emissions. The aim of this study is to carry out a systematic review of the current situation of CF assessment in academic institutions by analysing different key elements, such as the time period, methodologies and practises, calculation tools, emission sources, emission factors and reduction plans. The review protocol considered articles published until March 2021. Of the articles reviewed, 35 are aimed specifically at calculating the CF of HEI, while the remaining articles consist of review, activity-specific CF assessment or GHG emission reduction articles. Clear differences have been identified when results are compared for the normalised CF (average of 2.67 t CO2e/student, ranging from 0.06 to 10.94) or the percentage of carbon offsetting, only considered in 14% of the studies and ranging from 0.09 to 18%. The main reason for this is the lack of standardisation as regards the time metric (year, semester), functional unit (student, employee, area) and data collection boundary (scope 1, 2, 3), the emissions sources and emission factors, mainly for scope 3 (water consumption and treatment, waste treatment, office, ICT and laboratory consumables, commuting and travel, construction materials, canteens, etc.), and the inclusion or not of the effect of carbon offset projects to offset the CF (aim of the project and absorption sources and factors). However, despite the differences, a reduction over time is clearly observed. Therefore, CF in HEI requires further improvements and solutions to a number of challenges, including the definition of representative emission sources, the creation of a robust emission factor database and the development of tools/methodologies that cover all the needs of this type of organisation. Graphic abstract
PubDate: 2021-11-01
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- Impact of environmental strategies and practices on the socioeconomic
development of the Brazilian sugar-energy sector-
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Abstract: Different environmental strategies have been devised and implemented as instruments to change companies’ socio-environmental behavior worldwide. In this study, we investigated the motivations for implementing environmental strategies and practices in Brazilian mills, as well as their organizational profile, and evaluated the effects of adopting environmental practices on competitiveness. Through case studies using face-to-face interviews with key people, we surveyed six medium- and large-sized Brazilian mills. The results highlighted that the main motivations for implementing environmental strategies and practices in the mills were external and internal pressures, operational performance, and the improvement in competitiveness. In relation to external and internal pressures, environmental legislation and regulations, safety at work, and commodity trading were the parameters that guided the adoption of environmental strategies. Regarding operational performance, we observed that the mills linked environmental issues to an organizational structure in conjunction with the company’s strategic decisionmakers, as well as monitoring and treating soil, water, air, and sugarcane by-products and reducing and reusing by-products in order to prevent environmental impacts and reduce operating costs, which provided them with improvements in operational excellence. Our results also showed that the use of environmental strategies led to improvements in mills’ competitiveness, as it enhanced the company’s image in the most demanding markets and guaranteed a better position in the current market, besides raising employee satisfaction through participation in internal and external projects. Therefore, adopting environmental strategies and practices in the sugar-energy sector can contribute to improving the mill’s operational performance, reducing social pressures, and gaining competitive advantages, as well as leading to sustainable production. Graphic abstract
PubDate: 2021-11-01
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- Strategies to promote circular economy in the management of construction
and demolition waste at the regional level: a case study in Manaus, Brazil
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Abstract: Construction and Demolition Waste (CDW) cause environmental impacts in a worldwide scale. The existing international concern regarding the adequate management of CDW is justified by the large amount of this waste produced in a daily basis, together with its potential hazardous effects on ecosystems and human health. In this scope, the application of Circular Economy principles to the construction industry is of the utmost importance to define management strategies regarding CDW. Although highly dependent on policies developed at the national level, the promotion of circularity in construction materials usage is also at the reach of local administration bodies. The present research identifies strategies for CDW management at the regional level, involving different stakeholders of the construction industry. These strategies were successfully operationalized through a case study focusing CDW management in the municipality of Manaus, in the centre of the Amazon Forest. The characterization of the reference situation regarding CDW management in Manaus revealed several deficiencies, namely the lack of reuse and recycling opportunities, the unsupervised disposal of CDW in illegal landfills, together with insufficient surveillance procedures and inadequate policies from regional authorities. Improved CDW management strategies were identified and operationalized: valorization of CDW through the enhancement of reuse and recycling opportunities, operationalized through a mobile phone application; reinforcement of training and surveillance practices; and alterations in the municipal policies regarding CDW disposal in the public landfill. The CDW management strategies described and validated in this research are applicable to other Brazilian municipalities or to other countries’ realities, promoting sustainability-oriented practices that can co-exist with economic development. Graphic abstract
PubDate: 2021-11-01
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- Does environmental stress affect economic growth: evidence from the Gulf
Cooperation Council countries'-
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Abstract: The current paper empirically investigates the effect of environmental stress on economic growth in the Gulf Cooperation Council countries during 1995–2016. A panel cointegration analysis, specifically an autoregressive distributed lag model, is used to achieve the paper’s goal. The present work is motivated by the high carbon dioxide emissions per capita and environmental stress in these countries relative to other countries, and it assumes that the income per capita is a function of the natural resource’s rents and environmental stress. The findings show that environmental stress enhances economic growth, mainly in the long run. At the same time, the natural resources’ rents improve it in the short run and impede it in the long run. These results are significant because they tell that the Gulf Cooperation Council countries’ environmental stress did not reach critical levels that produce vast negative influences on the economy, and the resource curse hypothesis is valid in the long run. The current study’s policy implication states that economic policymakers should monitor and evaluate future environmental stress outcomes in these countries. There is no guarantee that the positive influence prevails. Therefore, the Gulf Cooperation Council countries should adopt genuine procedures to diversify their economies. Besides, it should continue its initial steps to expand renewable energy resources, i.e., nuclear, wind, and solar. Graphic abstract
PubDate: 2021-11-01
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- Emerging technology for sustainable production of bleached pulp from
recovered cardboard-
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Abstract: Post-use corrugated packaging cardboard is commonly known as old corrugated containers (OCC). They are complex and heterogeneous materials composed of various sources of unbleached cellulose pulp derived from several raw material processes which must be revalued due to its functionality, recyclability, and biodegradability. Besides, as recovered pulp have a greater composition of long fiber than short fiber because are mainly manufactured from softwood pulp by the kraft process. OCC are the main category of recovered paper; however, due to their high lignin content and hemicelluloses, additives, pollutants, hornification and degradation of fibers and other problems resulting from the pulp to cardboard conversion processes, their physical properties decrease with each recycling or reprocessing, which justifies evaluating a set of technologies to improve it. The objective of this work was to obtain improved unbleached and bleached OCC pulp more ecologically and economically justifiable than derived from wood chips for higher grade papers using sustainable processes evaluated in pilot scale tests. Mixed OCC were collected as waste from a landfill, cleaned, repulped, and treated with extended delignification with the alkaline soda process, obtaining a pulp with significant physical–mechanical improvements in relation to the original material, such as tensile strength, tearing resistance, bursting strength and folding endurance. The OCC soda pulp was bleached by a sequence totally free of chlorinated compounds (TCF), obtaining bleached pulp with optical and mechanical properties comparable to virgin pulps of annual plants such as bagasse but with improved drainage properties and lower processing costs. According to their properties, it is a competitive pulp obtained with emerging and existing technologies, available for use in various grades of printing and writing paper replacing totally or partially bleached wood pulp. Graphic
PubDate: 2021-11-01
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- Prioritizing novel wastewater-to-hydrogen production technologies based on
different decision-making approaches-
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Abstract: With the increasing population, the amount of wastewater that needs to be managed is also increasing. Population growth also increases energy demand. While treating wastewater containing organic matter and water, hydrogen energy can be produced at the same time. In this study, microbial fuel cells, dark fermentation, supercritical water gasification, and photobioreactors that produce hydrogen from wastewater have been evaluated and prioritized for the first time in terms of benefit, opportunity, cost, and risk criteria. The analytic hierarchy process (AHP) technique and benefit, opportunity, cost, and risk (BOCR) model have been used to achieve this aim. In addition, a sensitivity analysis was performed to determine critical criteria for prioritizing technologies. With the analytic hierarchy process technique, it was determined that the criterion with the highest priority was benefit (53%), while the sub-criterion with the highest priority was technological development (33%) followed by operating cost (15%) and compliance with sustainability (12%). Supercritical water gasification technology was found to be the top priority with the AHP technique. In the BOCR model, dark fermentation was determined to be the highest priority technology. In the sensitivity analysis, changes in the weights of the opportunity and cost criteria showed that these criteria were critical. The results obtained show that dark fermentation, which is a technology close to the development, is preferred in the first rank because it has less risk and can produce a high rate of hydrogen. This study could spur more R&D work for researchers to industrialize this technology. It can also give an idea for different studies to researchers. Graphic abstract
PubDate: 2021-11-01
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- The green solvent: a critical perspective
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Abstract: Solvents are important in most industrial and domestic applications. The impact of solvent losses and emissions drives efforts to minimise them or to avoid them completely. Since the 1990s, this has become a major focus of green chemistry, giving rise to the idea of the ‘green’ solvent. This concept has generated a substantial chemical literature and has led to the development of so-called neoteric solvents. A critical overview of published material establishes that few new materials have yet found widespread use as solvents. The search for less-impacting solvents is inefficient if carried out without due regard, even at the research stage, to the particular circumstances under which solvents are to be used on the industrial scale. Wider sustainability questions, particularly the use of non-fossil sources of organic carbon in solvent manufacture, are more important than intrinsic ‘greenness’. While solvency is universal, a universal solvent, an alkahest, is an unattainable ideal.
PubDate: 2021-11-01
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- A land-use-constrained, generation–transmission model for electricity
generation through solar photovoltaic technology: a case study of south
India-
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Abstract: Full exploitation of solar photovoltaic electricity generation potential is being pegged back by land availability and the imbalance between demand and generation capacity. In the present work, a land-use-constrained generation model is proposed to identify natural pathways for energy flows within a politically administered region so as to evolve a sustainable nexus between electricity generation and consumption in a decentralized power generation scenario. The model envisages district-level coordination of electricity generation on barren rocky waste land and state-level coordination of distribution. Application of the model to five south Indian states, individually and together, demonstrates how the model is able to account for intra- and interstate disparities in electricity consumption and photovoltaic electricity generation potential. Two of these states can go completely renewable by using all available barren rocky area for electricity generation while the other three will have to rely on as yet untapped off-shore wind power and nuclear power to move towards carbon neutrality in power generation. When considered together, almost all the day time electrical energy demand of all the states can be met by utilizing barren rocky waste land for harnessing solar energy, thus saving considerably on storage losses. Graphic abstract
PubDate: 2021-11-01
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- Effect of organic loading rate on the biological performance of the
thermophilic anaerobic membrane bioreactor treating pulp and paper primary
sludge-
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Abstract: Waste-to-energy or value-added products have been increasingly considered in many pulp and paper mills (PPMs) worldwide. However, developing appropriate conversion technologies are a major challenge in transforming PPMs wastes into biofuels or value-added biomaterials. In the present study, a long term (320 d) anaerobic digestion of primary sludge of a thermomechanical pulp mill (TMP) was carried out for the first time in a thermophilic anaerobic membrane bioreactor (ThAnMBR). Effect of organic loading rate (OLR) in the range of 2.5–6.8 kg COD/m3 d and hydraulic retention times (HRT) of 3–8 d on the process performance was investigated. Under various OLRs, stable biogas productions were obtained, and the best results were achieved with lower OLR (2.5 kg COD/m3 d) and higher HRT (8 d), at biogas yields of 189 L biogas/kg MLSS fed. However, it was found that the biogas production and sludge biomass degradation decrease when the organic loading rate increases. The proportion of sludge reduction ranged from 28.9 to 46.7% depending on the applied OLRs. Despite varying OLRs, stable membrane performance was obtained, where the required membrane flux was easily maintained during the reactor operation. In this study, also the properties of digestate and membrane permeates were studied under different operating conditions, and they fluctuated to some extent with OLR. ThAnMBR is a promising new technology for pulp and paper mill primary sludge treatment. Graphic abstract
PubDate: 2021-11-01
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- Ecological system for water treatment in fine chemicals industry
enterprises-
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Abstract: The issues of water management in chemical enterprises are considered to be very challenging and important at present. There are a significant number of studies devoted to individual stages of enterprises’ water management (water treatment, wastewater purification, etc.). For the first time, an integrated water management system (SWME) for the fine chemicals industry is proposed. The structure of the system is designed on a modular principle and consists of seven local subsystems: water recycling; steam generation, collection and treatment of condensate; desalted water production; high-purity water production; collection and treatment of polluted water; industrial water purification; and hot water. Balanced and interactive operation of all subsystems of SWME allows to reduce the water consumption of the enterprise as a whole by 20%, the loss of water, industrial and semi-pure wastewater, and the negative impact of the enterprise on the environment, while increase the efficiency and safety of production. Development of SWME was carried out under CALS (Continuous Acquisition and Life cycle Support) technologies—the most prospective system of computer support. The CALS technology of project design documentation (technological regulations) and an information model have been developed to optimize the input and retrieval of information at all levels of the hierarchy: an integrated system, a local subsystem, and equipment. Graphic abstract
PubDate: 2021-10-12
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- Environmental regulation, economic policy uncertainty, and green
technology innovation-
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Abstract: Green technology innovation is imperative to sustainable and environmentally sound economic development and is currently facing increasingly serious environmental threats. However, existing research has overlooked the uncertainties in economic policies. Based on the logical relationship between environmental regulation, economic policy uncertainty, and green technology innovation, this study empirically analyzed the quantitative relationship among these three variables using the fixed-effect panel method and provincial panel data from 2000 to 2017 for 30 administrative regions of China. The results show that environmental regulation is positively correlated with green innovation, whereas economic policy uncertainty has a negative influence on green innovation, thereby regulating the relationship between the remaining two factors. Moreover, considerable regional heterogeneity exists in these causal influences, i.e., environmental regulation promotes green innovation in the eastern and middle regions but not significantly in the west. The uncertainty actively moderates the impact of environmental regulation on green innovation in all regions with an adjustment coefficient of approximately 0.8; however, it inhibits green innovation in different degrees, especially in the eastern and middle regions. Based on empirical results, we conclude that strict and appropriate environmental regulations are necessary and effective in China to encourage green technology innovation, especially in regions with uncertain economic policies. Graphic abstract
PubDate: 2021-10-11
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