Pub Date : 2021-12-17DOI: 10.1080/21622515.2021.2011431
M. Misra, Soham Chattopadhyay, A. Sachan, Shashwati Ghosh Sachan
ABSTRACT Rapid urbanization and development of industries have led to the continuous addition of various wastes and hazardous chemicals into the environment, thus polluting it beyond limits. It is an issue of global concern as coming up with effective methods for remediation has become a challenge. The traditional methods for pollutant removal face serious drawbacks in terms of cost and generation of secondary pollutants, thus innovating simple and environment-friendly approaches becomes a priority. New technologies are being explored for the eradication of different contaminants, of which nanotechnology has shown immense potential. Biogenic nanoparticles are synthesized using different microbes and are further employed for the remediation of environmental pollutants. Complete degradation of Methylene Blue within 11 min and 98% degradation of Congo Red after 20 min were accomplished using gold nanoparticles, synthesized using cell-free extracts of Bacillus marisflavi in a recent study. Palladium nanoparticles, synthesized using Shewanella loihica PV-4 and Enterococcus faecalis, facilitated the complete reduction of toxic hexavalent chromium. This review focuses on microbe-mediated synthesis of nanomaterials and their prospect in the field of environmental remediation. GRAPHICAL ABSTRACT
{"title":"Microbially synthesized nanoparticles and their applications in environmental clean-up","authors":"M. Misra, Soham Chattopadhyay, A. Sachan, Shashwati Ghosh Sachan","doi":"10.1080/21622515.2021.2011431","DOIUrl":"https://doi.org/10.1080/21622515.2021.2011431","url":null,"abstract":"ABSTRACT Rapid urbanization and development of industries have led to the continuous addition of various wastes and hazardous chemicals into the environment, thus polluting it beyond limits. It is an issue of global concern as coming up with effective methods for remediation has become a challenge. The traditional methods for pollutant removal face serious drawbacks in terms of cost and generation of secondary pollutants, thus innovating simple and environment-friendly approaches becomes a priority. New technologies are being explored for the eradication of different contaminants, of which nanotechnology has shown immense potential. Biogenic nanoparticles are synthesized using different microbes and are further employed for the remediation of environmental pollutants. Complete degradation of Methylene Blue within 11 min and 98% degradation of Congo Red after 20 min were accomplished using gold nanoparticles, synthesized using cell-free extracts of Bacillus marisflavi in a recent study. Palladium nanoparticles, synthesized using Shewanella loihica PV-4 and Enterococcus faecalis, facilitated the complete reduction of toxic hexavalent chromium. This review focuses on microbe-mediated synthesis of nanomaterials and their prospect in the field of environmental remediation. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"11 1","pages":"18 - 32"},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44408264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-12-17DOI: 10.1080/21622515.2021.2010131
Emmanuella Anang, Liu Hong, Xianyuan Fan, Ebenezer Nestle Asamoah
ABSTRACT Polluted water continues to be a major problem globally since it deteriorates human health after consumption and impedes sustainable development. Nanoscale zero-valent iron (nZVI) has been used to tackle the problem, but certain significant disadvantages of the nZVI limit its efficiency. Owing to the demerits of nZVI, various materials have been employed to support the nZVI to ensure efficient decontamination. There is rising interest in using attapulgite as a support for nZVI. The use of attapulgite supported nanoscale zero-valent iron (A-nZVI) to decontaminate wastewater/groundwater has proven to be highly efficient as compared to unsupported nZVI. This paper presents an overview of the syntheses, performance, application and limitations of using A-nZVI to treat wastewater/remediate groundwater. A-nZVI has been extensively employed on laboratory scale, thus making it difficult to simulate its removal efficiency on a large scale. However, its high removal efficiency under the appropriate operational conditions make it ideal to be used on an industrial level. This review is important because it identifies gaps in literature with respect to A-nZVI that need to be filled to improve ZVI-based technology. GRAPHICAL ABSTRACT
{"title":"Attapulgite supported nanoscale zero-valent iron in wastewater treatment and groundwater remediation: synthesis, application, performance and limitation","authors":"Emmanuella Anang, Liu Hong, Xianyuan Fan, Ebenezer Nestle Asamoah","doi":"10.1080/21622515.2021.2010131","DOIUrl":"https://doi.org/10.1080/21622515.2021.2010131","url":null,"abstract":"ABSTRACT Polluted water continues to be a major problem globally since it deteriorates human health after consumption and impedes sustainable development. Nanoscale zero-valent iron (nZVI) has been used to tackle the problem, but certain significant disadvantages of the nZVI limit its efficiency. Owing to the demerits of nZVI, various materials have been employed to support the nZVI to ensure efficient decontamination. There is rising interest in using attapulgite as a support for nZVI. The use of attapulgite supported nanoscale zero-valent iron (A-nZVI) to decontaminate wastewater/groundwater has proven to be highly efficient as compared to unsupported nZVI. This paper presents an overview of the syntheses, performance, application and limitations of using A-nZVI to treat wastewater/remediate groundwater. A-nZVI has been extensively employed on laboratory scale, thus making it difficult to simulate its removal efficiency on a large scale. However, its high removal efficiency under the appropriate operational conditions make it ideal to be used on an industrial level. This review is important because it identifies gaps in literature with respect to A-nZVI that need to be filled to improve ZVI-based technology. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"11 1","pages":"1 - 17"},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44704746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1080/21622515.2021.1881829
P. N. Egbuikwem, G. Obiechefu, F. Hai, M. C. Devanadera, D. Saroj
ABSTRACT Pollution and increasing water demand, especially for agriculture, put severe stress on freshwater sources, and as a result, there is progressive deficit in the global water supply and severe water scarcity is projected in the coming decades. Discharges from domestic, industrial and agricultural activities are potential sources of water pollution, impacting human and environmental health. In the face of growing water scarcity and droughts, coupled with the increasing water demand for irrigation, integration of high water-volume and nutrient-rich industrial effluents, into the existing water management plans for agriculture, could play an important role in tackling the problem of water scarcity. However, there is a gap in knowledge about integration of industrial effluents to sewage treatments and the reuse potential of biologically treated mixed industrial and domestic wastewater in agriculture. This study, therefore, provides a critical review on biological treatment of industrial effluents, including petroleum, textile and pharmaceutical wastewater to better understand the capability of bioprocesses and conditions for efficient degradation of pollutants. The effectiveness of activated sludge-based processes, for the treatment of mixed industrial and domestic wastewater, was critically examined, and biomass acclimation plays a vital role in enhanced biodegradation performance. Finally, the reuse potential of mixed industrial and domestic wastewaters for crop irrigation was assessed by studying the reuse outcomes in different cases where industrial effluents were utilized for crop production. Management practices, such as cultivation of salt- and metal-tolerant crops, blending and dilution of industrial wastewater with freshwater and sewage, could make industrial effluents valuable for irrigation. GRAPHICAL ABSTRACT
{"title":"Potential of suspended growth biological processes for mixed wastewater reclamation and reuse in agriculture: challenges and opportunities","authors":"P. N. Egbuikwem, G. Obiechefu, F. Hai, M. C. Devanadera, D. Saroj","doi":"10.1080/21622515.2021.1881829","DOIUrl":"https://doi.org/10.1080/21622515.2021.1881829","url":null,"abstract":"ABSTRACT Pollution and increasing water demand, especially for agriculture, put severe stress on freshwater sources, and as a result, there is progressive deficit in the global water supply and severe water scarcity is projected in the coming decades. Discharges from domestic, industrial and agricultural activities are potential sources of water pollution, impacting human and environmental health. In the face of growing water scarcity and droughts, coupled with the increasing water demand for irrigation, integration of high water-volume and nutrient-rich industrial effluents, into the existing water management plans for agriculture, could play an important role in tackling the problem of water scarcity. However, there is a gap in knowledge about integration of industrial effluents to sewage treatments and the reuse potential of biologically treated mixed industrial and domestic wastewater in agriculture. This study, therefore, provides a critical review on biological treatment of industrial effluents, including petroleum, textile and pharmaceutical wastewater to better understand the capability of bioprocesses and conditions for efficient degradation of pollutants. The effectiveness of activated sludge-based processes, for the treatment of mixed industrial and domestic wastewater, was critically examined, and biomass acclimation plays a vital role in enhanced biodegradation performance. Finally, the reuse potential of mixed industrial and domestic wastewaters for crop irrigation was assessed by studying the reuse outcomes in different cases where industrial effluents were utilized for crop production. Management practices, such as cultivation of salt- and metal-tolerant crops, blending and dilution of industrial wastewater with freshwater and sewage, could make industrial effluents valuable for irrigation. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"10 1","pages":"77 - 110"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21622515.2021.1881829","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41556967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1080/21622515.2021.1892203
Lemnaro Jamir, Prof Vikas Kumar, J. Kaur, Satish Kumar, H. Singh
ABSTRACT The rise in population is driving up the global food demand, which, in turn, influences the processing of foods that leads to the ample generation of waste material throughout the world. Molasses is one of the wastes generated from the sugarcane processing industry by repeated crystallization during sugar preparation. The yield varies from 2.2 to –3.7% per tons of sugarcane. Due to its composition and economic importance, it is the major choice (as a carbon source) for food, feed and fermentation industries in the fructification of ethyl alcohol, liquor (rum), dry yeast, acetone, butanol, certain organic acids, etc. However, the on-going scenario of global research, the largest quantity of molasses is being utilized for the manufacture of ethanol. Traditionally, this is used for the manufacture of hukas, tobacco and liquors. However, due to its improper management, such as storage, packaging and transportation, the entire production of molasses is not being commercially utilized. It possesses numerous health benefits, such as antioxidant, anti-obese, anti-cancerous, antimicrobial, anti-anaemic, improves bone and hair health, used for the treatment of skin and anaemia. The present review is aimed to enlighten the composition, types of molasses, its respective utilization (traditional/conventional), health benefits and regulations. GRAPHICAL ABSTRACT
{"title":"Composition, valorization and therapeutical potential of molasses: a critical review","authors":"Lemnaro Jamir, Prof Vikas Kumar, J. Kaur, Satish Kumar, H. Singh","doi":"10.1080/21622515.2021.1892203","DOIUrl":"https://doi.org/10.1080/21622515.2021.1892203","url":null,"abstract":"ABSTRACT\u0000 The rise in population is driving up the global food demand, which, in turn, influences the processing of foods that leads to the ample generation of waste material throughout the world. Molasses is one of the wastes generated from the sugarcane processing industry by repeated crystallization during sugar preparation. The yield varies from 2.2 to –3.7% per tons of sugarcane. Due to its composition and economic importance, it is the major choice (as a carbon source) for food, feed and fermentation industries in the fructification of ethyl alcohol, liquor (rum), dry yeast, acetone, butanol, certain organic acids, etc. However, the on-going scenario of global research, the largest quantity of molasses is being utilized for the manufacture of ethanol. Traditionally, this is used for the manufacture of hukas, tobacco and liquors. However, due to its improper management, such as storage, packaging and transportation, the entire production of molasses is not being commercially utilized. It possesses numerous health benefits, such as antioxidant, anti-obese, anti-cancerous, antimicrobial, anti-anaemic, improves bone and hair health, used for the treatment of skin and anaemia. The present review is aimed to enlighten the composition, types of molasses, its respective utilization (traditional/conventional), health benefits and regulations. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"10 1","pages":"131 - 142"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21622515.2021.1892203","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42501937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1080/21622515.2021.1921056
Z. Ho, R. Bahar, C. Koo
ABSTRACT The main focus of this review is to investigate the potential of small-scale solar desalination as a viable freshwater source by comparing the performance of different types of modification on solar stills. The design factors that could provide impacts to the parameters affecting the performance in terms of distillate production have been considered. The design factors include mostly the different mechanisms of solar stills, concentration of solar power,sand thermal storage. The impacted parameters of each type of solar stills are one of the highlights of this review. The cost of production has also been explored. The purpose of this review is to enable future researchers in identifying the appropriate features to be used for designing a solar desalination system in water and energy-stressed rural regions. The minimum cost per liter of water production reported was 0.0085 USD and the maximum production reported from modified passive solar still was reported to be 11.65 L/m2/day with a spherical absorber. Minor addition of active elements like a small pump to the still with Fresnel absorber reported producing 12.47 L/m2 day. For performance enhancement of passive solar stills in water and energy scarce regions, it is suggested to add Phase change material (PCM) with heat conductive particles and solar irradiation concentration through absorbers/reflectors or Fresnel lenses. HIGHLIGHTS Renewable energy based desalination methods are preferable over energy-intensive methods. For water and energy scarce regions, independent small scale passive solar stills can be a viable option. Parameters affecting the performance of a solar still include uncontrollable climatic parameters and manipulative parameters. Highly productive passive solar stills can be designed by controlling the manipulative parameters like evaporation area of the basin, tilt angle and temperature of condensation surface, thermal gain of the feedwater by thermal storage, heat transfer using fins/conductive material in the basin. The recent trends to improve passive solar stills’ efficiency with cost effectiveness include usage of sunlight concentrators through refraction, addition of conductive nano particles with thermal storage and multi-staging. GRAPHICAL ABSTRACT
{"title":"A comprehensive review on small-scale passive solar stills for desalination","authors":"Z. Ho, R. Bahar, C. Koo","doi":"10.1080/21622515.2021.1921056","DOIUrl":"https://doi.org/10.1080/21622515.2021.1921056","url":null,"abstract":"ABSTRACT The main focus of this review is to investigate the potential of small-scale solar desalination as a viable freshwater source by comparing the performance of different types of modification on solar stills. The design factors that could provide impacts to the parameters affecting the performance in terms of distillate production have been considered. The design factors include mostly the different mechanisms of solar stills, concentration of solar power,sand thermal storage. The impacted parameters of each type of solar stills are one of the highlights of this review. The cost of production has also been explored. The purpose of this review is to enable future researchers in identifying the appropriate features to be used for designing a solar desalination system in water and energy-stressed rural regions. The minimum cost per liter of water production reported was 0.0085 USD and the maximum production reported from modified passive solar still was reported to be 11.65 L/m2/day with a spherical absorber. Minor addition of active elements like a small pump to the still with Fresnel absorber reported producing 12.47 L/m2 day. For performance enhancement of passive solar stills in water and energy scarce regions, it is suggested to add Phase change material (PCM) with heat conductive particles and solar irradiation concentration through absorbers/reflectors or Fresnel lenses. HIGHLIGHTS Renewable energy based desalination methods are preferable over energy-intensive methods. For water and energy scarce regions, independent small scale passive solar stills can be a viable option. Parameters affecting the performance of a solar still include uncontrollable climatic parameters and manipulative parameters. Highly productive passive solar stills can be designed by controlling the manipulative parameters like evaporation area of the basin, tilt angle and temperature of condensation surface, thermal gain of the feedwater by thermal storage, heat transfer using fins/conductive material in the basin. The recent trends to improve passive solar stills’ efficiency with cost effectiveness include usage of sunlight concentrators through refraction, addition of conductive nano particles with thermal storage and multi-staging. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"10 1","pages":"188 - 212"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21622515.2021.1921056","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46280147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1080/21622515.2021.1960642
Simon D. Fairbanks, S. Pramanik, Jim A. Thomas, Amitiva Das, N. Martin
ABSTRACT Dental restorative material mercury amalgam - which is composed of approximately 50% mercury - has been used for centuries. Although many alternatives to amalgam are available or under development, its mechanical, inert, durable and cost-effective properties mean that globally it is still the predominant filling material in dental practices. Current expert opinion is that, in a clinical setting, amalgam is safe and well tested, with clinical studies revealing no adverse health effects to amalgam fillings. Nevertheless, in line with the Minamata convention, the use of mercury amalgam is being phased down. More significantly, although waste disposal methods have developed considerably, the ultimate environmental fate of dental mercury is not fully delineated; furthermore, the amount of mercury in the environment from historical poor practice is still largely unknown. In this review an overview of how mercury is managed and disposed of in modern dental clinics is provided. Recent best estimates for mercury consumption in dental applications are discussed and compared to total global mercury consumption. The ultimate environmental sinks for the metal are identified and the methods currently employed to process products that are highly deleterious to the environment and human health are described. With a focus on environmentally mobile and highly toxic alkyl mercury compounds, some of the possible environmental implications that could occur with poor waste management are also outlined. GRAPHICAL ABSTRACT
{"title":"The management of mercury from dental amalgam in wastewater effluent","authors":"Simon D. Fairbanks, S. Pramanik, Jim A. Thomas, Amitiva Das, N. Martin","doi":"10.1080/21622515.2021.1960642","DOIUrl":"https://doi.org/10.1080/21622515.2021.1960642","url":null,"abstract":"ABSTRACT Dental restorative material mercury amalgam - which is composed of approximately 50% mercury - has been used for centuries. Although many alternatives to amalgam are available or under development, its mechanical, inert, durable and cost-effective properties mean that globally it is still the predominant filling material in dental practices. Current expert opinion is that, in a clinical setting, amalgam is safe and well tested, with clinical studies revealing no adverse health effects to amalgam fillings. Nevertheless, in line with the Minamata convention, the use of mercury amalgam is being phased down. More significantly, although waste disposal methods have developed considerably, the ultimate environmental fate of dental mercury is not fully delineated; furthermore, the amount of mercury in the environment from historical poor practice is still largely unknown. In this review an overview of how mercury is managed and disposed of in modern dental clinics is provided. Recent best estimates for mercury consumption in dental applications are discussed and compared to total global mercury consumption. The ultimate environmental sinks for the metal are identified and the methods currently employed to process products that are highly deleterious to the environment and human health are described. With a focus on environmentally mobile and highly toxic alkyl mercury compounds, some of the possible environmental implications that could occur with poor waste management are also outlined. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"10 1","pages":"213 - 223"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42804855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1080/21622515.2021.1989060
A. Mohammad, Venkata Siva Naga Sai Goli, Petra Martínez Barroso, M. Vaverková, D. Singh
ABSTRACT Composting enables microbial decomposition of biodegradable organic fractions of municipal solid waste (OFMSW) and converts them into a valuable resource having profuse application in agriculture and horticulture. The efficiency of composting, primarily, would depend upon physico-chemico-biological properties of the feedstock (moisture content, particle size and organic matter) and operational parameters (temperature, aeration rate and frequency, presence of bulking agents and microorganisms). However, lack of appropriate selection of the initial physico-chemico-biological properties of municipal solid waste (MSW) and inadequate maintenance of operational conditions during composting results in generating low-quality end products with undesirable characteristics, such as phytotoxicity and nutrients-deficiency. Also, the release of toxic elements, greenhouse gases and volatile organic compounds (odorants) into the environment are other major issues related to composting technology, which need immediate attention of the researchers. Hence, a critical synthesis of the literature has been conducted to understand the effect of different (i) physical (particle size, moisture content), (ii) chemical (pH, elemental composition), (iii) biological (type of microorganisms, enzymatic activities) and (iv) operational (temperature, aeration strategy, turning frequency, addition of bulking agents) parameters on the composting of OFMSW and emission of major gaseous products. Furthermore, by utilizing the available data in the literature, several trends have been developed to depict the impact of substrate characteristics and operational conditions on compost quality and emission of gaseous products. These relationships would be instrumental in devising general recommendations on the selection of initial properties of MSW to (i) obtain superior quality compost and (ii) reduce the emission of harmful gaseous products during composting. GRAPHICAL ABSTRACT
{"title":"Effect of physico-chemico-biological and operational parameters on composting of organic fraction of municipal solid waste and gaseous products emission: review","authors":"A. Mohammad, Venkata Siva Naga Sai Goli, Petra Martínez Barroso, M. Vaverková, D. Singh","doi":"10.1080/21622515.2021.1989060","DOIUrl":"https://doi.org/10.1080/21622515.2021.1989060","url":null,"abstract":"ABSTRACT Composting enables microbial decomposition of biodegradable organic fractions of municipal solid waste (OFMSW) and converts them into a valuable resource having profuse application in agriculture and horticulture. The efficiency of composting, primarily, would depend upon physico-chemico-biological properties of the feedstock (moisture content, particle size and organic matter) and operational parameters (temperature, aeration rate and frequency, presence of bulking agents and microorganisms). However, lack of appropriate selection of the initial physico-chemico-biological properties of municipal solid waste (MSW) and inadequate maintenance of operational conditions during composting results in generating low-quality end products with undesirable characteristics, such as phytotoxicity and nutrients-deficiency. Also, the release of toxic elements, greenhouse gases and volatile organic compounds (odorants) into the environment are other major issues related to composting technology, which need immediate attention of the researchers. Hence, a critical synthesis of the literature has been conducted to understand the effect of different (i) physical (particle size, moisture content), (ii) chemical (pH, elemental composition), (iii) biological (type of microorganisms, enzymatic activities) and (iv) operational (temperature, aeration strategy, turning frequency, addition of bulking agents) parameters on the composting of OFMSW and emission of major gaseous products. Furthermore, by utilizing the available data in the literature, several trends have been developed to depict the impact of substrate characteristics and operational conditions on compost quality and emission of gaseous products. These relationships would be instrumental in devising general recommendations on the selection of initial properties of MSW to (i) obtain superior quality compost and (ii) reduce the emission of harmful gaseous products during composting. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"10 1","pages":"271 - 294"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43189567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1080/21622515.2021.1900404
Yang Li, Xia Li
ABSTRACT Water distribution systems play a vital role in the transportation of drinking water. By the combination of traditional literature review, bibliometric analysis and scientific knowledge mapping, this study evaluated 6,968 related literatures extracted from the database of Science Citation Index-Expanded from 1998 to 2019 to quantitatively analyze and visualize current research hotspots and emerging trends. The results revealed that water quality and optimal design of systems were research hotspots in the early periods, however in recent years, certain keywords that are more in accord with the characteristics of the times such as climate change, resilience, leak detection and energy recovery have appeared with high frequency, indicating that the research on water distribution systems might have turned from the study of single system to the overall consideration of the system and external environment. Therefore, the future studies may focus on (1) impact of climate change on water distribution systems (2) research on the resilience of urban water supply infrastructure (3) more accurate leak detection and more effective leakage control management (4) energy efficiency improvement and energy recovery in water distribution systems. GRAPHICAL ABSTRACT
{"title":"Research on water distribution systems from the past to the future: a bibliometric review","authors":"Yang Li, Xia Li","doi":"10.1080/21622515.2021.1900404","DOIUrl":"https://doi.org/10.1080/21622515.2021.1900404","url":null,"abstract":"ABSTRACT\u0000 Water distribution systems play a vital role in the transportation of drinking water. By the combination of traditional literature review, bibliometric analysis and scientific knowledge mapping, this study evaluated 6,968 related literatures extracted from the database of Science Citation Index-Expanded from 1998 to 2019 to quantitatively analyze and visualize current research hotspots and emerging trends. The results revealed that water quality and optimal design of systems were research hotspots in the early periods, however in recent years, certain keywords that are more in accord with the characteristics of the times such as climate change, resilience, leak detection and energy recovery have appeared with high frequency, indicating that the research on water distribution systems might have turned from the study of single system to the overall consideration of the system and external environment. Therefore, the future studies may focus on (1) impact of climate change on water distribution systems (2) research on the resilience of urban water supply infrastructure (3) more accurate leak detection and more effective leakage control management (4) energy efficiency improvement and energy recovery in water distribution systems. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"10 1","pages":"161 - 176"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21622515.2021.1900404","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45745784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1080/21622515.2021.1994658
Rabia Sabir, A. Waheed, M. Moazzam Ali, Umar Mushtaq
ABSTRACT Graphene (G), a two-dimensional carbon layer, is regarded as twenty-first century wonder material and due to its remarkable physio-chemical properties it has been explored for application in various science and technology areas. In environmental remediation field, the quest for eco-friendly and green processes has put a growing emphasis on solar-driven photocatalysis. The conventional semiconductor photocatalysts suffer with the shortcoming of electron–hole pair recombination, aggregation and wide band gap, which inhibit their commercialization. Coupling of graphene derivatives, such as graphene oxide (GO) and reduced graphene oxide (RGO), with semiconductors (TiO2, ZnO) offers a considerable potential to enhance the photocatalytic efficiency by providing higher surface area, stability, and fast electron conduction ability. Numerous papers have been published in recent years which couples Graphene, GO and RGO with different semiconductors for photocatalytic degradation of various organic pollutants. So, it is high time a comprehensive review should be presented to understand the potential and future prospects of photocatalysis in water treatment. This article aims to provide a critical review about recent progress in fabrication methods, modification techniques (non-metal or metal doping), efficiency and mechanism for organic pollutant photo degradation and visible light activation of graphene-based photocatalysts. The role of graphene in photocatalysis and organic pollutant degradation mechanism is summarized. Moreover, novel graphene and layered double hydroxide (LDH) composites are also discussed as potential candidates in wastewater treatment. Furthermore, future prospects and challenges such as separation, recyclability and health hazards of these composites are discussed to provide an outlook about their practical application in water purification. GRAPHICAL ABSTRACT
{"title":"Graphene-based photocatalysts for organic pollutant removal from waste-water: recent progress and future challenges","authors":"Rabia Sabir, A. Waheed, M. Moazzam Ali, Umar Mushtaq","doi":"10.1080/21622515.2021.1994658","DOIUrl":"https://doi.org/10.1080/21622515.2021.1994658","url":null,"abstract":"ABSTRACT\u0000 Graphene (G), a two-dimensional carbon layer, is regarded as twenty-first century wonder material and due to its remarkable physio-chemical properties it has been explored for application in various science and technology areas. In environmental remediation field, the quest for eco-friendly and green processes has put a growing emphasis on solar-driven photocatalysis. The conventional semiconductor photocatalysts suffer with the shortcoming of electron–hole pair recombination, aggregation and wide band gap, which inhibit their commercialization. Coupling of graphene derivatives, such as graphene oxide (GO) and reduced graphene oxide (RGO), with semiconductors (TiO2, ZnO) offers a considerable potential to enhance the photocatalytic efficiency by providing higher surface area, stability, and fast electron conduction ability. Numerous papers have been published in recent years which couples Graphene, GO and RGO with different semiconductors for photocatalytic degradation of various organic pollutants. So, it is high time a comprehensive review should be presented to understand the potential and future prospects of photocatalysis in water treatment. This article aims to provide a critical review about recent progress in fabrication methods, modification techniques (non-metal or metal doping), efficiency and mechanism for organic pollutant photo degradation and visible light activation of graphene-based photocatalysts. The role of graphene in photocatalysis and organic pollutant degradation mechanism is summarized. Moreover, novel graphene and layered double hydroxide (LDH) composites are also discussed as potential candidates in wastewater treatment. Furthermore, future prospects and challenges such as separation, recyclability and health hazards of these composites are discussed to provide an outlook about their practical application in water purification. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"10 1","pages":"323 - 341"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42751782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1080/21622515.2021.1913242
Arti Malviya, D. Jaspal
ABSTRACT Artificial intelligence (AI) is nowadays an upcoming technology. It is a practice of simulating human intelligence for varied applications. When compared with the standard practices, AI is developing at a rapid rate. AI has proved its worth in several areas such as agriculture, automobile industry, banking and finance, space exploration, artificial creativity, etc. Owing to the efficiency, speed, and independence from human operations, AI is now entering the wastewater treatment sector. This technology has been used for monitoring the performance of the water treatment plants in terms of efficiency parameters, Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) determination, elimination of nitrogen and sulphur, prediction of turbidity and hardness, uptake of contaminants, etc., in the wastewater sector. Artificial Neural Networks (ANN), Fuzzy Logic Algorithms (FL), and Genetic Algorithms (GA) are the basic three models under AI predominantly used in the wastewater sector. Studies reveal that the determination coefficient values of 0.99 can be attained for COD, BOD, heavy metals and organics removal using ANN and hybrid intelligent systems. This review paper describes research with all the possible models of AI utilized in the water treatment which have enhanced the pollutant removal percentage accuracy of ranging from 84% to 90% and provided viewpoint on future directions of novel research, in the field with due focus on pollution remediation, cost effectiveness, energy economy, and water management. GRAPHICAL ABSTRACT
{"title":"Artificial intelligence as an upcoming technology in wastewater treatment: a comprehensive review","authors":"Arti Malviya, D. Jaspal","doi":"10.1080/21622515.2021.1913242","DOIUrl":"https://doi.org/10.1080/21622515.2021.1913242","url":null,"abstract":"ABSTRACT Artificial intelligence (AI) is nowadays an upcoming technology. It is a practice of simulating human intelligence for varied applications. When compared with the standard practices, AI is developing at a rapid rate. AI has proved its worth in several areas such as agriculture, automobile industry, banking and finance, space exploration, artificial creativity, etc. Owing to the efficiency, speed, and independence from human operations, AI is now entering the wastewater treatment sector. This technology has been used for monitoring the performance of the water treatment plants in terms of efficiency parameters, Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) determination, elimination of nitrogen and sulphur, prediction of turbidity and hardness, uptake of contaminants, etc., in the wastewater sector. Artificial Neural Networks (ANN), Fuzzy Logic Algorithms (FL), and Genetic Algorithms (GA) are the basic three models under AI predominantly used in the wastewater sector. Studies reveal that the determination coefficient values of 0.99 can be attained for COD, BOD, heavy metals and organics removal using ANN and hybrid intelligent systems. This review paper describes research with all the possible models of AI utilized in the water treatment which have enhanced the pollutant removal percentage accuracy of ranging from 84% to 90% and provided viewpoint on future directions of novel research, in the field with due focus on pollution remediation, cost effectiveness, energy economy, and water management. GRAPHICAL ABSTRACT","PeriodicalId":37266,"journal":{"name":"Environmental Technology Reviews","volume":"10 1","pages":"177 - 187"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21622515.2021.1913242","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44058772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：