Microalgae have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production.However,the high energy cost associated with complicated b...Microalgae have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production.However,the high energy cost associated with complicated biorefinery(e.g.microalgae cultivation,harvesting,drying,extraction,conversion,and purification)is a critical challenge that inhibits its large-scale application.Among different nutrition(e.g.carbon,nitrogen and phosphorous)sources,food processing wastewater is a relative safe and suitable one for microalgae cultivation due to its high organic content and low toxicity.In this review,the characteristic of different food wastewater is summarized and compared.The potential routes of value-added products(i.e.biofuel,pigment,polysaccharide,and amino acid)production along with wastewater purification are introduced.The existing challenges(e.g.biorefinery cost,efficiency and mechanism)of microalgal-based wastewater treatment are also discussed.The prospective of microalgae-based food processing wastewater treatment strategies(such as microalgae-bacteria consortium,poly-generation of bioenergy and value-added products)is forecasted.It can be observed that food wastewater treatment by microalgae could be a promising strategy to commercially realize waste source reduce,conversion and reutilization.展开更多
Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and...Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and crops at two peri urban areas in Zambia. Two study sites were New Farm Extension in Mufulira Town in the Copperbelt Province and Chilumba Gardens in Kafue Town in Lusaka Province. The heavy metals investigated were lead, copper, cobalt, nickel and chromium. These heavy metals were found to be higher than acceptable limits in wastewater used to irrigate crops and there are potential human health risks associated with consumption of heavy metal contaminated food crops which have implications on the livelihoods of people. Samples of water, soil and crops were collected and analysed for lead (Pb), copper (Cu), chromium (Cr), cobalt (Co) and nickel (Ni) using the Atomic Absorption Spectrometer (AAS). The data on heavy metals was analysed using mean, standard error and T-test. The results indicated that the levels of heavy metals in wastewater, soil and food crops were above acceptable limits at two study sites. It can be concluded that there was heavy metal contamination of wastewater, soil and food crops at the two peri-urban areas in Zambia. The study highlighted the actual levels of heavy metal contaminant uptake in food crops consumed by the peri urban population. The information from this study can be used by the relevant authorities to develop appropriate measures for monitoring and control of heavy metal contamination in wastewater irrigation farming systems in peri urban areas inZambia.展开更多
Although wastewater irrigation in agriculture could be a potential adaptation to water scarcity, its effect on crop yield varies in the literature, making it difficult to evaluate its role in global food security comp...Although wastewater irrigation in agriculture could be a potential adaptation to water scarcity, its effect on crop yield varies in the literature, making it difficult to evaluate its role in global food security comprehensively. Using agronomic experiment data from 62 studies between 1987 and 2021, we employ a meta-analysis to analyze the factors contributing to the heterogeneous effects of wastewater irrigation on crop yield. Our findings can be summarized as(1) the mean yield growth effect of wastewater irrigation is 19.7%;(2) domestic and breeding wastewater irrigation could significantly increase crop yield, while industrial wastewater has a negative effect although not significant;(3) high nutrients concentration of domestic wastewater is significantly positively correlated with crop yield;(4) agronomic experiment designs in terms of field experiment, experiment times, and fertilizer use could contribute to the divergent crop yield effects across the studies;(5) there is a publication bias of the research results between the English and Chinese literature;(6) the literature mainly sheds light on the short-run effect, and the long-run impact shall be an important research question in the future.展开更多
This review discusses high-strength wastewater treatment using anaerobic baffled reactors(ABRs)and modified ABRs.The research findings and applications of ABRs in treating various types of high strength wastewater gen...This review discusses high-strength wastewater treatment using anaerobic baffled reactors(ABRs)and modified ABRs.The research findings and applications of ABRs in treating various types of high strength wastewater generated from food companies,livestock,and industries were summarized and reported.Measurement parameters affecting the performance of ABRs are briefly discussed.The state-of-the-art laboratory studies are compiled and critically reviewed.Critical challenges and suggestions for future investigation are also addressed.展开更多
低强度进水制约了城镇污水处理厂的总氮(TN)脱除效果。采用易腐垃圾沼液作为补充碳源,在强化污水处理厂脱氮效果的同时,降低了污水处理和易腐垃圾沼液运行成本及碳排放量。实验分析了沼液成分,并研究了不同沼液/进水混合比对污染物去除...低强度进水制约了城镇污水处理厂的总氮(TN)脱除效果。采用易腐垃圾沼液作为补充碳源,在强化污水处理厂脱氮效果的同时,降低了污水处理和易腐垃圾沼液运行成本及碳排放量。实验分析了沼液成分,并研究了不同沼液/进水混合比对污染物去除、运行稳定性及污泥性状的影响。结果表明,当混合比为0.100%(体积分数)时,工艺具有最佳运行效果。沼液投加后生化段反硝化速率增加了2.23倍,同步硝化反硝化(SND)效率增加了39.2%,TN去除率提高了1.34倍。污水处理厂出水水质稳定,达到《城镇污水处理厂主要水污染物排放标准》(DB 33/2169—2018)(“准四类”排放标准)。工艺流程中重金属(Pb、Cd及Cr)含量均未超标,出水的环境污染风险可控。沼液的资源化利用每年约减少污水处理厂运行成本38万元,易腐垃圾运行成本144万元,并削减近84 t CO_(2)排放。结果表明,对易腐垃圾沼液的资源化利用“以污治污”,有助于碳减排目标的实现,降低了运行成本,并具有良好的社会和环境效益。展开更多
基金Supported by the National key Research and Development project(2016YFB0601003)National Natural Science Foundation of China(21878228 and31701526)+3 种基金Basic Research Fees of Universities and Colleges in Tianjin(2017KJ001)Youth Teacher Innovation Fund of Tianjin University of Science&Technology(2015LG26)Project Program of Key Laboratory of Food Nutrition and Safety,Ministry of Education,China(2018007)Open Project program of State Key Laboratory of Food Nutrition and Safety,Tianjin University of Science&Technology(SKLFNS-KF-201824).
文摘Microalgae have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production.However,the high energy cost associated with complicated biorefinery(e.g.microalgae cultivation,harvesting,drying,extraction,conversion,and purification)is a critical challenge that inhibits its large-scale application.Among different nutrition(e.g.carbon,nitrogen and phosphorous)sources,food processing wastewater is a relative safe and suitable one for microalgae cultivation due to its high organic content and low toxicity.In this review,the characteristic of different food wastewater is summarized and compared.The potential routes of value-added products(i.e.biofuel,pigment,polysaccharide,and amino acid)production along with wastewater purification are introduced.The existing challenges(e.g.biorefinery cost,efficiency and mechanism)of microalgal-based wastewater treatment are also discussed.The prospective of microalgae-based food processing wastewater treatment strategies(such as microalgae-bacteria consortium,poly-generation of bioenergy and value-added products)is forecasted.It can be observed that food wastewater treatment by microalgae could be a promising strategy to commercially realize waste source reduce,conversion and reutilization.
文摘Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and crops at two peri urban areas in Zambia. Two study sites were New Farm Extension in Mufulira Town in the Copperbelt Province and Chilumba Gardens in Kafue Town in Lusaka Province. The heavy metals investigated were lead, copper, cobalt, nickel and chromium. These heavy metals were found to be higher than acceptable limits in wastewater used to irrigate crops and there are potential human health risks associated with consumption of heavy metal contaminated food crops which have implications on the livelihoods of people. Samples of water, soil and crops were collected and analysed for lead (Pb), copper (Cu), chromium (Cr), cobalt (Co) and nickel (Ni) using the Atomic Absorption Spectrometer (AAS). The data on heavy metals was analysed using mean, standard error and T-test. The results indicated that the levels of heavy metals in wastewater, soil and food crops were above acceptable limits at two study sites. It can be concluded that there was heavy metal contamination of wastewater, soil and food crops at the two peri-urban areas in Zambia. The study highlighted the actual levels of heavy metal contaminant uptake in food crops consumed by the peri urban population. The information from this study can be used by the relevant authorities to develop appropriate measures for monitoring and control of heavy metal contamination in wastewater irrigation farming systems in peri urban areas inZambia.
基金supported by the National Social Science Fund of China(20CSH048,20AZD024 and 21ZDA062)the National Natural Science Foundation of China(71773099)+1 种基金the Humanities and Social Sciences Project Funded by the Ministry of Education,China(21YJC790110)the Rural Finance Survey of the Ministry of Agriculture and Rural Affairs,China(05190084)。
文摘Although wastewater irrigation in agriculture could be a potential adaptation to water scarcity, its effect on crop yield varies in the literature, making it difficult to evaluate its role in global food security comprehensively. Using agronomic experiment data from 62 studies between 1987 and 2021, we employ a meta-analysis to analyze the factors contributing to the heterogeneous effects of wastewater irrigation on crop yield. Our findings can be summarized as(1) the mean yield growth effect of wastewater irrigation is 19.7%;(2) domestic and breeding wastewater irrigation could significantly increase crop yield, while industrial wastewater has a negative effect although not significant;(3) high nutrients concentration of domestic wastewater is significantly positively correlated with crop yield;(4) agronomic experiment designs in terms of field experiment, experiment times, and fertilizer use could contribute to the divergent crop yield effects across the studies;(5) there is a publication bias of the research results between the English and Chinese literature;(6) the literature mainly sheds light on the short-run effect, and the long-run impact shall be an important research question in the future.
文摘This review discusses high-strength wastewater treatment using anaerobic baffled reactors(ABRs)and modified ABRs.The research findings and applications of ABRs in treating various types of high strength wastewater generated from food companies,livestock,and industries were summarized and reported.Measurement parameters affecting the performance of ABRs are briefly discussed.The state-of-the-art laboratory studies are compiled and critically reviewed.Critical challenges and suggestions for future investigation are also addressed.
文摘低强度进水制约了城镇污水处理厂的总氮(TN)脱除效果。采用易腐垃圾沼液作为补充碳源,在强化污水处理厂脱氮效果的同时,降低了污水处理和易腐垃圾沼液运行成本及碳排放量。实验分析了沼液成分,并研究了不同沼液/进水混合比对污染物去除、运行稳定性及污泥性状的影响。结果表明,当混合比为0.100%(体积分数)时,工艺具有最佳运行效果。沼液投加后生化段反硝化速率增加了2.23倍,同步硝化反硝化(SND)效率增加了39.2%,TN去除率提高了1.34倍。污水处理厂出水水质稳定,达到《城镇污水处理厂主要水污染物排放标准》(DB 33/2169—2018)(“准四类”排放标准)。工艺流程中重金属(Pb、Cd及Cr)含量均未超标,出水的环境污染风险可控。沼液的资源化利用每年约减少污水处理厂运行成本38万元,易腐垃圾运行成本144万元,并削减近84 t CO_(2)排放。结果表明,对易腐垃圾沼液的资源化利用“以污治污”,有助于碳减排目标的实现,降低了运行成本,并具有良好的社会和环境效益。