Subjects -> ENVIRONMENTAL STUDIES (Total: 913 journals)
    - ENVIRONMENTAL STUDIES (810 journals)
    - POLLUTION (31 journals)
    - TOXICOLOGY AND ENVIRONMENTAL SAFETY (54 journals)
    - WASTE MANAGEMENT (18 journals)

WASTE MANAGEMENT (18 journals)

Showing 1 - 17 of 17 Journals sorted alphabetically
Advances in Recycling & Waste Management     Open Access   (Followers: 2)
Energy, Sustainability and Society     Open Access   (Followers: 15)
Exposure and Health     Hybrid Journal  
International Journal of Waste Resources     Open Access   (Followers: 5)
Journal of Hazardous, Toxic, and Radioactive Waste     Full-text available via subscription   (Followers: 6)
Journal of Material Cycles and Waste Management     Hybrid Journal   (Followers: 1)
Journal of Paper Conservation     Hybrid Journal   (Followers: 2)
Journal of Solid Waste Technology and Management     Full-text available via subscription   (Followers: 4)
Journal of Waste Management     Open Access   (Followers: 4)
Journal of Water and Wastewater / Ab va Fazilab     Open Access  
npj Clean Water     Open Access  
Open Waste Management Journal     Open Access   (Followers: 1)
Resources, Conservation & Recycling Advances     Open Access   (Followers: 1)
Waste Disposal & Sustainable Energy     Hybrid Journal  
Waste Management     Hybrid Journal   (Followers: 13)
Water-Energy Nexus     Open Access   (Followers: 2)
Worldwide Waste : Journal of Interdisciplinary Studies     Open Access   (Followers: 1)
Similar Journals
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Waste Disposal & Sustainable Energy
Number of Followers: 0  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 2524-7980 - ISSN (Online) 2524-7891
Published by Springer-Verlag Homepage  [2469 journals]
  • Experimental study on conversion path of sulfur in coal slime preheating
           combustion

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      Abstract: Abstract In this study, coal slime was mainly utilized to conduct experiments on a 30 kW preheating combustion test rig to analyze the conversion pathway of sulfur during the experiment, aiming at reducing slime pollution, controlling sulfur emission reasonably, and providing theoretical support for the preheating combustion technology. The results showed that after the coal slime was preheated, a large number of elements were released. The maximum release rates for H and S were 94.0% and 73.3%, respectively. The released S was converted into the sulfur-containing gases like H2S, COS, CS2, and the rest existed in the solid in the five forms of mercaptan, thiophene, sulfoxide, sulfone, and sulfate. Besides, during the combustion process, the gas was oxidized continuously and finally converted into SO2, leaving only the sulfate in the fly ash. In the preheating combustion process, 26.7% of the S was released from the coal, 73.3% of the S was retained in the semi-coke, and the final SO2 emission concentration of combustion was 959 ppm.
      PubDate: 2022-04-01
       
  • Utilization of leather fibrous wastes for the production of reconstituted
           fibric materials: heavy metal determination and removal

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      Abstract: Abstract Incomprehension concerning heavy metal containing finished solid leather wastes leads to environmental pollution. Conversion of these solid leather waste into energy and resource efficient products proves to be challenging. However, leather microfibres (LMF) were isolated from these heavy metal containing finished solid leather wastes. These heavy metal contain LMF further processed into metal reduction LMF. The metal reduction LMF were investigated for their heavy metal removal efficiency and toxicity analysis. The Cr (III) and Cr (VI) content of LMF was <1000 µg/mL and <800 µg/mL, respectively. Toxicity estimation was proved that the LMF had less than 1%. The study attempt to prepare reconstituted fibric materials (RFM) from metal reduction LMF and cellulose nanofibres (CNF). RFM were characterized for their physicochemical and mechanical properties. Hence, the study has proved a novel concept of RFM production which is recyclable, environmental friendly and cost effective.
      PubDate: 2022-03-21
       
  • Characterization of the temperature and oxygen concentration field in a
           decentralized solid-waste incinerator for villages and towns

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      Abstract: Abstract Decentralized solid-waste incinerators (DSWIs) have certain advantages for waste disposal from villages and towns. However, the incineration condition is always affected by the distribution of temperature and oxygen concentration, which causes difficulties in operation and maintenance. In this study, the temperature and oxygen concentration distribution of DSWI were characterized using different air flow rates and bottom ash volumes. The results showed that the adjustment of air flow has no significant influence on the heating process of the DSWI, while the retention of bottom ash did affect the temperature and oxygen concentration fields in the furnace. When the air flow rate was increased without the retention of bottom ash, 99% of the furnace volume temperature was observed between 780 °C and 800 °C. However, once the bottom ash was retained, the whole furnace temperature was steadily maintained between 800 °C and 850 °C. When the air flow rate was increased without bottom ash, the highest furnace volume percentage of oxygen concentrations higher than 3% maxed out at 11% volume, while it could reach 100% when bottom ash remained. The distribution of the temperature and oxygen concentration in the DSWI characterized by this research provides strong support for the operation and management of such systems.
      PubDate: 2022-03-14
       
  • Resource utilization of solid waste carbide slag: a brief review of
           application technologies in various scenes

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      Abstract: China is the largest producer and consumer of calcium carbide in the world. The calcium carbide industry is an indispensable industry to support the basic life of people. The huge production capacity of calcium carbide is accompanied by a large number of solid waste carbide slag. Due to the immature treatment technology of carbide slag, a large number of carbide slag are stacked on-site, resulting in land occupation, air-drying, easy take-off ash, and pollution of the environment and water resources. In China, calcium carbide is mainly used to produce acetylene and further utilized, 80% of which is used to produce polyvinyl chloride (PVC). A large amount of carbide slag is not used, while only a small part is used in the traditional building materials industry, flue gas desulfurization, sewage treatment, etc., however, the economic benefits are poor. Therefore, converting the solid waste carbide slag produced by the calcium carbide industry into high value-added CaCO3, CaCl2, CaSO4 whiskers, etc. has become a potential way to expand the development field of the calcium carbide industry and is environmentally friendly. This paper focuses on summarizing the traditional and emerging high value-added utilization technologies of carbide slag, and then introduces the application research of carbide slag in carbon emission reduction. Finally, the defects of these technologies are summarized and further research directions are prospected. This study provides basic guidance for the diversified development of efficient resource utilization of carbide slag. Graphical abstract Diversified development of calcium carbide industry, resource utilization of solid waste carbide slag and its application of carbon emission reduction have been fully reviewed.
      PubDate: 2022-03-01
      DOI: 10.1007/s42768-021-00090-z
       
  • Appropriate solid waste management system in Quelimane (Mozambique): study
           and design of a small-scale center for plastic sorting with wastewater
           treatment

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      Abstract: Abstract Appropriate solid waste management (SWM) strategies are necessary to avoid severe environmental and sanitary impacts, especially in low-income countries. Such strategies are most likely to succeed whether implementing actors are supported by scientific research. In this paper, the results of a collaboration between local authorities and researchers are presented and discussed that are the assessment of waste generation in the city of Quelimane (Mozambique), integrating existing and field-collected data and the design of a small-scale center for plastic sorting to complement the SWM system of the city. The center is expected to receive about 0.3–0.4 t/day of plastic waste (5%–7% of the overall amount of plastic waste daily produced in Quelimane). As long-term sustainability represents a typical issue, simplicity of operation was a leading principle in the design of the center; moreover, the design included a treatment plant (WWTP) for generated wastewater, whose management is usually neglected in such interventions. Among others, natural wastewater treatment (constructed wetlands) has been chosen for its affordability. Noteworthy, the so-conceived WWTP appears as a novelty in the scientific literature associated with small-scale plastic sorting plants. The system is designed to treat an average flow of 6 m3/day and consisted of a septic tank followed by a subsurface flow constructed wetland. Overall, the COD (chemical oxygen demand) and TSS (total suspended solids) removal higher than 80% and 90% were estimated, respectively. Based on this work, both the center and the WWTP were successfully realized, which are waiting to become operational. In the authors’ opinion, the implemented procedure could become a reference for broader investigations and surveys.
      PubDate: 2022-02-21
      DOI: 10.1007/s42768-022-00091-6
       
  • Fly ash and zero-valent iron-based in situ advanced anaerobic digestion
           with emphasis on the removal of antibiotics and antibiotic resistance
           genes from sewage sludge

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      Abstract: Abstract This study investigated the removal of antibiotics and antibiotic resistance genes from sewage sludge by using fly ash (FA)-based in situ advanced anaerobic digestion (AAD) under mesophilic conditions. Five antibiotics (sulfadiazine, sulfamethoxazole, ofloxacin, tetracycline, and roxithromycin) and 11 corresponding antibiotic resistance genes (Ib-cr, qnrS, ermF, ermT, ermX, sul1, sul2, sul3, tetA, tetB, and tetG) were selected as the targets. Adding FA to anaerobic digestion to remove antibiotics and resistance genes allows waste to be treated with waste. FA-based in situ AAD of sewage sludge effectively enhanced the process stability and methane yield, and the optimal FA-added dosage was 50 mg/L. The cumulative methane yield could be well described with the improved Gompertz model. FA addition effectively increased the overall removal of ofloxacin, by up to 85.3% at 50 mg/L FA and 10 μg/L antibiotics, and the combination of zero-valent iron and FA enhanced only the overall removal of ofloxacin to 92.4% and tetracycline to 85.6%. However, FA-based in situ AAD could not enhance the overall removal of other antibiotics from sewage sludge. Not all the same types of antibiotic resistance genes were strongly positively correlated with the concentrations of antibiotics. The removal of antibiotic resistance genes influenced by FA addition varied largely with the types of antibiotic resistance genes, FA dosage, antibiotic content, and the combination with zero-valent iron. FA addition could not be verified to enhance the removal of antibiotic resistance genes. The addition of FA or zero-valent iron and the antibiotic concentrations significantly changed the microbial community structure during in situ AAD, and the combination of zero-valent iron and FA significantly reduces the species diversity and microbial abundance. The most abundant bacteria were Methanogarcina, Methanoberium, unidentified_Archaea, Terrimonas, Methomethoxychlorovorans, and Candidatus_Cloacimonas in the ZVI-FA test.
      PubDate: 2022-01-31
      DOI: 10.1007/s42768-021-00089-6
       
  • Waste to energy (WTE) in China: from latecomer to front runner

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      Abstract: Abstract This paper discusses the 2000–2018 evolution of energy and metals recovery from urban wastes in the European Union and China. As a result of the zero-landfilling directive, in twenty years the European Union tripled its recycling rate (11%–30%) and its composting rate (6%–17%), doubled its WTE rate (14%–28%) and more than halved its landfilling (64%–25%). At the beginning of this century, the rapidly growing cities of China were literally surrounded by landfills. Therefore, the national government instituted policies, such as a credit of US$30 per MWh of WTE (waste to energy) electricity that resulted in the construction, by 2020, of 510 WTE plants with an annual WTE capacity of 193 million tons. In comparison, the European Union (EU) WTE capacity is 96 million tons and the USA has remained static at about 27 million tons, i.e., 10% of its post-recycling MSW (municipal solid waste), with the other 90% being landfilled. In the first decade of this century, two WTE technologies, moving grate and circulating fluid bed were developed in China at about the same rate. However, since 2010, the moving grate technology has become dominant and the WTE plants are built functionally and esthetically comparable to and U.S. plants.
      PubDate: 2021-12-18
      DOI: 10.1007/s42768-021-00086-9
       
  • Co-pyrolysis of cassava peel with synthetic polymers: thermal and kinetic
           behaviors

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      Abstract: Abstract This research effort focuses on the co-pyrolysis of cassava peels waste and some synthetic polymers towards energy conversion and reducing the volume of these waste fractions dumped on dumpsites. The co-pyrolysis behavior and pyrolysis kinetics of various synthetic polymer wastes/cassava peel blends were investigated by blending cassava peel waste with low-density polyethylene (LDPE), polyethylene terephthalate (PET), and polystyrene (PS) at different weight ratios. The physical characteristics of each sample were investigated and the co-pyrolysis experiments were conducted at a heating rate of 10 °C/min from room temperature to 800 °C in N2 atmosphere in a thermogravimetric analyzer. Subsequent to thermal decomposition, kinetic analysis was done using the thermogravimetric data. Results from physicochemical characterization showed that cassava peel has a relatively lower calorific value of 15.92 MJ/kg compared with polystyrene (41.1 MJ/kg), low-density polyethylene (42.6 MJ/kg), and polyethylene terephthalate (21.1 MJ/kg). The thermal decomposition behavior of cassava peel was seen to be significantly different from those of the synthetic polymers. The decomposition of the biomass material such as cassava peel generally occurs in two stages while the decomposition of LDPE, PS, and PET occurred in a single stage. The activation energy required for thermal degradation in cassava peel was also found to be lower to that of the plastic material. The co-pyrolysis of cassava peel and different synthetic polymers affected the thermal and kinetic behaviors of the blends, reduce the activation energy and residue after pyrolysis.
      PubDate: 2021-12-17
      DOI: 10.1007/s42768-021-00085-w
       
  • Environmental consequences of an ultra-low emission retrofit in coal-fired
           power plants from a life cycle perspective

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      Abstract: Abstract To make coal-fired power generation more environmentally friendly, China has initiated a series of ultra-low emission retrofits to the air pollution control (APC) system of the existing power plants. In this study, a life cycle assessment (LCA) is conducted to analyze the environmental net benefits for the typical ultra-low emission retrofit of a 1000 MW power plant. The key processes, substances, and APC devices are verified and discussed. The results confirm that the retrofit effectively decreases the environmental stress of acidification potential (AP), eutrophication potential (EP), and photochemical ozone creation potential (POCP) by 69%–79%, which can be attributed to significantly reduced emissions at the stack. However, the retrofit has also increased other impact categories by 24%–79%, primarily due to the consumption of additional electricity and adsorbents. The retrofit of selective catalytic reduction, electrostatic precipitator (ESP), and wet limestone flue gas desulfurization devices has a dominant effect on the impacts of EP, human toxicity potential (HTP), and AP. A newly installed wet ESP shows some environmental benefits (only for AP), but causes considerable burdens, in particular for the investigated impact categories global warming potential (GWP), marine aquatic ecotoxicity (MAETP), and abiotic depletion fossil (ADP fossil). The obtained results indicate that the hidden environmental consequences, which are associated with the production of energy and materials, need to be examined more comprehensively to inform the development of ultra-low emission technologies and strategies effectively.
      PubDate: 2021-12-17
      DOI: 10.1007/s42768-021-00083-y
       
  • In-situ sampling investigation of deposition and corrosion of convective
           heating surfaces in a grate type municipal solid waste incineration plant:
           a case study

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      Abstract: Abstract Metal corrosion and ash deposition are two common issues in municipal solid waste incineration (MSWI) plants. An in-situ sampling investigation was conducted in an MSWI plant in Jiangsu, China. The deposit samples were collected from 6 convective heating surfaces including the reheaters, superheaters, and economizer. The corrosion samples were obtained from a ruptured tube cut from the tertiary superheater. The element composition, crystal phases, and morphology of deposit and corrosion samples were characterized and analyzed. The results show that S contents of these deposits are 32–45 wt%, considerable Cl (10.63 wt%) was only detected in the deposits of the tertiary superheater. The composition of the deposits varies with the location because the flue gas temperature determines the thermodynamic trend of the sulfation reactions of different chlorides and the SO2 equilibrium partial pressure required in these reactions. Ca sulfates mainly exist in deposits at high temperatures (above approximately 500 °C). Whereas alkali metal sulfates are the main component of deposits at low temperatures (below approximately 500 °C). A multi-layer structure is exhibited on the cross-section of the corrosion samples. The discovery of Cl in the interface between the matrix and the oxide layer confirms that Cl can penetrate the outer oxide film. Besides, polysulfate components were observed inside the metal oxide layers, which indicates that a melt has occurred there. This study has provided a better understanding of ash deposition and corrosion phenomena in MSWI systems and more emphasis should be placed on the research of ash deposition and corrosion mechanisms.
      PubDate: 2021-12-02
      DOI: 10.1007/s42768-021-00087-8
       
  • Characterization of municipal solid waste based on seasonal variations,
           source and socio-economic aspects

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      Abstract: Abstract Municipal solid waste (MSW) generation and characterization are the basic inputs for waste handling and treatment systems design. In present research, we performed waste characterization investigations in Visakhapatnam (India), using a waste characterization methodology by integrating two standard sampling and characterization approaches. The characterization methodology was designed by combining seasonal variations, source, and socio-economic stratifications. Source-based sampling was performed at household(s), dumpster(s), transfer station, and landfill. Socio-economic-based sampling was performed based on the zone classification of the city. Three sampling campaigns were conducted to identify the waste composition based on seasonal variations. Studies aimed to perform stratified characterization of waste and assess chemical characteristics of the mixed waste fractions to evaluate waste-to-energy potential. Results indicate that the amount of MSW generated in the city is 1250±100 tons/day, with a generation rate of 0.65 kg/capita/day. Based on source stratification, organic matter (45.5% ± 6.5%) is a major component followed by inert waste. The paper, plastic, and textile components amount to 25% of overall waste. From seasonal studies, organic matter was higher in pre-monsoon (42%) compared to winter (39%). The moisture content of MSW varied between 30% and 35% and volatile solids between 39% and 43%. The calorific value was determined to be between 5680 – 7110 kJ/kg. Outlined the limitations and potential errors associated with sampling and waste characterization. Biochemical and thermal conversion treatment alternatives for processing, treatment, and handling were discussed. The findings of this research would assist regulatory bodies and city councils to formulate policy directives on waste sampling, characterization, segregation, education, and awareness campaigns.
      PubDate: 2021-11-30
      DOI: 10.1007/s42768-021-00084-x
       
  • Co-combustion of RDF and biomass mixture with bituminous coal: a case
           study of clinker production plant in Egypt

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      Abstract: Cement clinker production in Egypt till 2013 relied mainly on fossil fuel as a primary energy source. However, with multiple fossil fuel shortages, the utilization of biomass wastes was initiated by multiple cement producers. In the current work, and to present an industrial-scale biomass and coal co-combustion study, the utilization of multiple biomass fuels to substitute a portion of bituminous coal was studied in an Egyptian clinker production plant. Mixtures of biomass fuels were used to reduce the consumption of bituminous coal and to investigate the diminishing of the environmental impact of the clinker production process. The current study was conducted during 8 days of the stable clinker production process by replacing 14% of bituminous coal with biomass mixtures while monitoring the major process control parameters and resulting emissions. Emission results were compared to the nation’s regulations. A conclusion can be made that using biomass mixtures as alternative fuels minimized the dependency on coal as the main fuel and reduced the CO2 burden of the cement production process. In addition, NOx and SO2 emissions were declined while CO emissions were increased by utilizing biomass mixtures as alternative fuels; all emissions, however, were below the allowable limits stated by the Egyptian environmental authority. Noticeably, the heavy elements, dioxins, and furans were not changed significantly compared to those produced using coal only. Graphic abstract
      PubDate: 2021-11-18
      DOI: 10.1007/s42768-021-00081-0
       
  • Optimizing flow field in an SCR system of a 600 MW power plant: effects
           of static mixer alignment style

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      Abstract: Abstract The fluid flow in a selective catalytic reduction (SCR) system of a 600 MW power station is optimized using the numerical simulation method in this work. Given that guide plates and straightening gratings are properly installed, the relative standard deviation (Cv) of velocity related to the inlet of an ammonia injection grid (AIG) and catalysts satisfy the engineering demand of <15%, suggesting that a relatively uniform velocity field is obtained. The in-line arrangement of static mixers strengthens the disturbance of fluid, promoting the mixing of reductant NH3 with flue gas. The NH3 mole fraction Cv value correlated to the inlet of catalysts drops to ca. 3.5%, which is lower than that in the cases when the mixers are aligned in a staggered style. These results indicate that a solid foundation is achieved for the effective abatement of NOx in practical applications.
      PubDate: 2021-11-17
      DOI: 10.1007/s42768-021-00082-z
       
  • Effect of N2 and Ar on CO2 conversion with segmented micro-plasma reactor

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      Abstract: Abstract The increase of CO2 concentration in the atmosphere has brought serious greenhouse effects and environmental problems, so it is urgent to solve the problem of excessive CO2 concentration. The carbon capture, utilization, and storage technology refer to the use of CO2 as a C1 resource to generate new economic benefits in a new production process. In this work, the influence of adding different proportions of N2 and Ar to the CO2 gas on the discharge characteristics and reaction performance was investigated with a newly designed dielectric barrier discharge (DBD) micro-plasma segmented electrode reactor and optical emission spectroscopy. The results indicated that the discharge current value increased when the added N2 content was less than 50%, and decreased when the N2 content exceeded 50% under the condition of constant input power. The number and the current value of mixed gas micro-discharges showed a decreasing trend with the increase of Ar content. In the discharge system, the dielectric capacitance (Cd) and the gas gap capacitance (Cg) showed opposite trends with the increase of N2 and Ar content. The dielectric capacitance decreased and the gas gap capacitance increased as the N2 content increased, while the trend was just the opposite as the Ar content increased. In addition, adding a small amount of N2 and Ar was conducive to the conversion of CO2, but when the N2 and Ar content exceeded 50%, the amount of CO2 converted will be reduced.
      PubDate: 2021-11-08
      DOI: 10.1007/s42768-021-00080-1
       
  • Correction to: Missing Conflict of Interest statements in previously
           published articles

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      PubDate: 2021-09-01
      DOI: 10.1007/s42768-021-00078-9
       
  • Solid state anaerobic digestion of water poor feedstock for methane yield:
           an overview of process characteristics and challenges

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      Abstract: Abstract Solid state anaerobic digestion (SSAD) of water poor feedstock may be a promising technology for energy recovery. Feedstocks having high solid concentration like lignocellulosic biomass, crop residues, forestry waste and organic fraction of municipal waste may be the appropriate feedstock for its biochemical conversion into energy carries like biomethane through SSAD. Compared to liquid state anaerobic digestion (LSAD), SSAD can handle higher organic loading rates (OLR), requires less water and smaller reactor volume and may have lower energy demand for heating or stirring and higher volumetric methane productivity. Besides these, pathogen inactivation may also be achieved in SSAD of biodegradable waste. Around 60% of recently built AD systems have adopted SSAD technology. However, the process stability of an SSAD system may have several constraints like limited mass transfer, process inhibitors and selection of digester type and should be addressed prior to the implementation of SSAD technology. In this article, a comprehensive overview of the key aspects influencing the performance of SSAD is discussed along with the need for mathematical modelling approaches. Further to this, reactor configuration for SSAD and digestate management requirement and practice for solid-state condition are reviewed for a better insight of SSAD technology
      PubDate: 2021-09-01
      DOI: 10.1007/s42768-021-00076-x
       
  • Review of low-temperature plasma nitrogen fixation technology

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      Abstract: Abstract Nitrogen fixation is essential for all forms of life, as nitrogen is required to biosynthesize fundamental building blocks of creatures, plants, and other life forms. As the main method of artificial nitrogen fixation, Haber–Bosch process (ammonia synthesis) has been supporting the agriculture and chemical industries since the 1910s. However, the disadvantages inherent to the Haber–Bosch process, such as high energy consumption and high emissions, cannot be ignored. Therefore, developing a green nitrogen fixation process has always been a research hotspot. Among the various technologies, plasma-assisted nitrogen fixation technology is very promising due to its small scale, mild reaction conditions, and flexible parameters. In the present work, the basic principles of plasma nitrogen fixation technology and its associated research progress are reviewed. The production efficiency of various plasmas is summarized and compared. Eventually, the prospect of nitrogen fixation using low-temperature plasma in the future was proposed.
      PubDate: 2021-09-01
      DOI: 10.1007/s42768-021-00074-z
       
  • Numerical study on the role of microwave–metal discharge in
           microwave pyrolysis of WPCBs

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      Abstract: Abstract As a promising green technology, microwave heating is highlighted by its high efficiency and low consumption, especially in the fast pyrolysis treatment for e-waste recycling. Electric discharge induced by microwave–metal interaction plays a significant role in the process, and its contribution to heat generation is, however, always hard to define qualitatively through direct experiments. In this simulation, a microwave heating model featuring the pulsed microwave–metal (MW-m) discharge was designed in multi-dimensions, using COMSOL Multiphysics software, to emphatically probe the depth and extent of the hot-spot effect as well as its auxo-action on the pyrolysis process of waste printed circuit boards (WPCBs). The energy loss generated by MW-m discharge was added into the models in the form of a built-in fluctuating heat source, and it is found that at a relatively low microwave energy-to-heat conversion rate (31.5%, 220.5 W), due to the unique thermal effect of microwave–metal discharge, it can achieve an ideal pyrolysis effect. Based on the results, the instantaneous heat by discharge is generated in the similar trend of radiation pulses, and the local temperature of discharge spots can reach more than 2000 K the instant the discharge occurs, shortening the overall pyrolysis from dozens of minutes to around 200 s.
      PubDate: 2021-09-01
      DOI: 10.1007/s42768-021-00079-8
       
  • Investigation on the Hg0 adsorption performance of Na2S- and S0-modified
           ZSM-5 adsorbent

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      Abstract: Abstract In this study, a series of Na2S- and S0-decorated ZSM-5 adsorbents were prepared and their Hg0 adsorption performance was evaluated. Given that S0 and Na2S were co-doped with the mass ratio of S0 to ZSM-5 fixed to 2:1, Hg0 removal efficiency quadruples compared with raw ZSM-5 and reached ca. 100% at 300 °C. Combined with the characterization results, it could be concluded that chemical properties, instead of physical structures, played an important role in Hg0 removal. Among the various gas components, O2, NO, and SO2 made negligible impacts on Hg0 capture over 2:1-S/ZSM-5 adsorbent surface. After recycling four times, Hg0 removal efficiency of 2:1-S/ZSM-5 adsorbent remained higher than 80%, which was indicative of a certain recyclability. Finally, XPS results illustrated that S0 and S2− on 2:1-S/ZSM-5 surface functioned as the active sites for the transformation of Hg0 to HgS, which facilitated the chemisorption process and consequently led to an improved Hg0 capture performance.
      PubDate: 2021-09-01
      DOI: 10.1007/s42768-021-00077-w
       
  • Experimental study on the partial preheating combustion characteristic of
           Yankuang coal sludge

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      Abstract: Abstract Coal sludge is a seriously polluted solid waste, and the rational utilization of its resources has long being an undoubtedly important research topic. This paper mainly studies the coal sludge partial preheating characteristic, combustion characteristic and the process of migration and conversion of nitrogen with preheating combustion technology. The experimental results indicate that most of the elements in the coal sludge are released during preheating, and the ratio of the fuel-N converted to the N2, NH3 and HCN are 75.5%, 6.74% and 0.64%, respectively. Compared with the coal sludge, the BET surface area and cumulative pore area of preheated char are increased. The surface of preheated char is loose and porous with many fine particles, while raw coal is dense with larger particles. Meantime, the quantity of carbon defect structure, the active sites and the reactivity of preheated char are all increased. In the whole process, the NOx emission is about 156 mg/m3 (@6% O2), the ratio of fuel-N converted to NOx was 2.98%, and the combustion efficiency is 96.5%. This experiment results will play a vital role in efficient and clean utilization of coal sludge.
      PubDate: 2021-09-01
      DOI: 10.1007/s42768-021-00073-0
       
 
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