Rural domestic sewage treatment is an important part of the rural revitalization strategy and a key action to build a livable, livable and beautiful countryside. This paper composes and summarizes the relevant studies...Rural domestic sewage treatment is an important part of the rural revitalization strategy and a key action to build a livable, livable and beautiful countryside. This paper composes and summarizes the relevant studies on rural domestic sewage treatment from the governance techniques and modes of governance subjects and research perspectives, in order to provide reference for the implementation of rural revitalization strategy and rural domestic sewage treatment research and action implementation.展开更多
[Objectives] By reasonable water distribution and air supply to soil, soil water permeability is maintained, and the nutrient conditions of degrading bacteria in soil are improved to effectively prevent soil clogging....[Objectives] By reasonable water distribution and air supply to soil, soil water permeability is maintained, and the nutrient conditions of degrading bacteria in soil are improved to effectively prevent soil clogging. [Methods] Through the innovation and improvement of traditional soil sewage treatment technology, the physical, chemical and biological characteristics of soil for sewage purification are utilized to enhance the pollutant decomposition ability of soil microorganisms and maintain soil water permeability.[Results] It has no secondary pollution, and can effectively remove pollutants such as COD_(Cr), TN, TP, NH_3-N, etc. in sewage. [Conclusions] The operation and maintenance cost is low, and the land can be reused, while water and nutrients can be restored to the land.展开更多
With the development of rural economy, pollutions of rural sewage are in- creasingly serious. This paper introduces the characteristics of rural domestic sewage and the rural sewage treatment situation, and according ...With the development of rural economy, pollutions of rural sewage are in- creasingly serious. This paper introduces the characteristics of rural domestic sewage and the rural sewage treatment situation, and according to the problems of funds, management, process selection, policy and weak awareness of environmental protection in the rural domestic sewage treatment, puts forward relevant countermea- sures to ensure long-term operation of sewage treatment system, and achieve the purpose of improving rural water environment and protect the ecological environment in rural areas.展开更多
Biotransformation of nonylphenol ethoxylates (NPEOs) during continuous anaerobic sewage treatment was compared with the aerobic treatment of sewage spiked with 23 μmol/L technical NPEOs over a period of 90 d. Immed...Biotransformation of nonylphenol ethoxylates (NPEOs) during continuous anaerobic sewage treatment was compared with the aerobic treatment of sewage spiked with 23 μmol/L technical NPEOs over a period of 90 d. Immediate degradation of NPEOs was observed under both anaerobic and aerobic conditions, indicating that the enzymes and bacteria required for NPEO degradation existed abundantly in both aerobic and anaerobic sludge. Both treatments achieved high removal (〉 92%) of the spiked NPEO9 mixture. Liquid chromatography-mass spectrometry (LC-MS) analysis showed that short-chain NPEOs (NPEO1-NPEO3) accumulated in anaerobic (2.01-2.56 μmol/L) and aerobic (1.62-2.03 μmol/L) effluents, with nonylphenol (NP) (0.24-0.31 μmol/L) as another group of metabolites in the anaerobic effluent, and nonylphenoxy carboxylates (NPECs) (2.79-3.30 μmol/L) in the aerobic effluent. Significant accumulation of NP in the anaerobic sludge and NPEO1-3 in the sludge of two reactors was observed. These results indicated that it was difficult to control these harmful metabolites in the conventional treatment processes. Denaturing gradient gel electrophoresis profiles of sludge samples support the speculation that the NPEO degradation bacteria might be the dominant indigenous species.展开更多
It is generally believed that intelligent management for sewage treatment plants(STPs) is essential to the sustainable engineering of future smart cities.The core of management lies in the precise prediction of daily ...It is generally believed that intelligent management for sewage treatment plants(STPs) is essential to the sustainable engineering of future smart cities.The core of management lies in the precise prediction of daily volumes of sewage.The generation of sewage is the result of multiple factors from the whole social system.Characterized by strong process abstraction ability,data mining techniques have been viewed as promising prediction methods to realize intelligent STP management.However,existing data mining-based methods for this purpose just focus on a single factor such as an economical or meteorological factor and ignore their collaborative effects.To address this challenge,a deep learning-based intelligent management mechanism for STPs is proposed,to predict business volume.Specifically,the grey relation algorithm(GRA) and gated recursive unit network(GRU) are combined into a prediction model(GRAGRU).The GRA is utilized to select the factors that have a significant impact on the sewage business volume,and the GRU is set up to output the prediction results.We conducted a large number of experiments to verify the efficiency of the proposed GRA-GRU model.展开更多
The problem of water pollution is one of the long-term difficulties in the process of rural environmental construction and economic development in China.In order to meet the requirements of the country’s green and su...The problem of water pollution is one of the long-term difficulties in the process of rural environmental construction and economic development in China.In order to meet the requirements of the country’s green and sustainable development,many regions actively promote the construction of rural sewage treatment and fill in the shortcomings of the rural habitat environment to accelerate the construction of beautiful and livable villages.Through a lot of literature and case studies,this paper explores the environmental problems that are common in rural sewage treatment in the northern region of China,explores advanced domestic and foreign cases and technologies on this topic,and summarizes the landscape design strategies on this issue.From the perspective of ecological landscape design,the thesis seeks the theoretical and technical support for rural sewage treatment in river valley areas,and establishes a bridge between rural sewage treatment technology and ecological landscape.Finally,combining theory with practice,taking the project of Lushi sewage treatment in Sanmenxia as an example,team completed the landscape design of ecological sewage purification display area in Zhangjiacun.The design focuses on presenting the application of internal sewage treatment technology and external landscape aesthetics.According to the main points of ecological landscape design and the theory of ecological edge effect,the local ecological system is effectively protected,and a rural domestic sewage purification display area with economic benefits is constructed.展开更多
Based on the statistics from the China Statistical Yearbook (2000-2009) on environment and methods recommended by the IPCC, the amounts of greenhouse gas (GHG) emissions from domestic and industrial sewage treatme...Based on the statistics from the China Statistical Yearbook (2000-2009) on environment and methods recommended by the IPCC, the amounts of greenhouse gas (GHG) emissions from domestic and industrial sewage treatment in China are estimated for the period of 2003-2009. CO2 emissions per capita from sewage treatment plants are also analyzed. The results show that the GHG emissions from sewage treatment plants increased steadily from 2003 to 2009; N20 emissions from domestic sewage are the major source of the total GHG emissions from domestic sewage; CH4 emissions from domestic sewage increase with the greatest speed; CH4 emissions from paper and pulp industry are the major source of industrial sewage emissions; CO2 emissions per capita increase constantly from 2003 to 2009.展开更多
Existing problems of sewage treatment plants in small towns were summarized firstly,and then the developing trend of construction of sewage treatment plants in small towns was discussed from the aspects of project dec...Existing problems of sewage treatment plants in small towns were summarized firstly,and then the developing trend of construction of sewage treatment plants in small towns was discussed from the aspects of project decision,site selection,design,processing technology and construction financing models. Finally,outlooks for its future development were proposed to provide reference for the construction of sewage treatment plants in small towns in future.展开更多
[Objective] The research aimed to study influence factors of phosphorus removal by chemical method in sewage treatment system. [ Method] In different reaction systems, removal effect of the phosphorus in sewage by dos...[Objective] The research aimed to study influence factors of phosphorus removal by chemical method in sewage treatment system. [ Method] In different reaction systems, removal effect of the phosphorus in sewage by dosing lime and influence of the constraint factor were stud- ied. [ Result] Lime precipitation method treating high-concentration phosphorus wastewater could not only decline cost of phosphorus removal by chemical method, but also reach better treatment effect under suitable stirring and precipitation conditions by controlling alkalinity and pH. Phosphor- us content of chemical sludge after treatment could reach 9% -12%, with higher recyclable value. E Conclusion] Lime method treating phosphorus- rich sewage was more economic than low-concentration phosphorus sewage, and had very great potential for recycling phosphorus.展开更多
Microplastic pollution has become a worldwide issue.The discharge of sewage treatment plants(STPs)or wastewater treatment plant(WWTPs)is an important way for microplastics to enter the environment.This study reviewed ...Microplastic pollution has become a worldwide issue.The discharge of sewage treatment plants(STPs)or wastewater treatment plant(WWTPs)is an important way for microplastics to enter the environment.This study reviewed the sources and occurrence characteristics(type,size,color and components)of microplastics in domestic and foreign sewage plants.It elaborated the removal principles of microplastics by primary,secondary and tertiary treatments.In addition,the removal effects of various treatment units and different processes on microplastics were summarized.In the future,the removal mechanism of microplastics in sewage treatment plants should be discussed in more depth,so as to further improve the removal rate of microplastics by optimizing and transforming traditional sewage treatment processes.Therefore,it is necessary to develop new technologies/processes specifically for the removal of microplastics and promote them to practical applications.展开更多
Daily influent quantity forecasting plays an important role in sewage treatment plant design and operation. Its uncertain factors are classified into three categories including day types, weather conditions and specia...Daily influent quantity forecasting plays an important role in sewage treatment plant design and operation. Its uncertain factors are classified into three categories including day types, weather conditions and special events, of which the latter two are considered with a BP (Back Propagation) model. On this basis, the daily period feature is taken into account in the presented model. The data from a practical sewage treatment plant utility is employed to show the effectiveness of the method.展开更多
The estrogenic activity of influents and effluents of five municipal sewage treatment works (STWs) in Nanjing was investigated. The water samples were enriched by solid phase extraction, then eluted with different p...The estrogenic activity of influents and effluents of five municipal sewage treatment works (STWs) in Nanjing was investigated. The water samples were enriched by solid phase extraction, then eluted with different polar solvents, and f'mally three fractionated extracts were obtained. Estrogen receptor recombinant yeast screen was used to evaluate the estrogenic activity of individual fractionated extracts and their mixture. The results show that the influents and effluents of the two STWs mainly receiving industrial wastewater have no obvious estrogenic activity, and the water samples from the other three STWs mainly receiving domestic wastewater show different degrees of estrogenic activity. The total estrogenic concentration ranged from 171. 52 ng/L EEQ (E2 - equivalent concentration) to 1 008.37 ng/L EEQ in the influents, and from ND (not detected) to 36.3 ng/L EEQ in the effluents. By comparing the results of different fractionated extracts, the methanol and dichloromethane extracts of the water samples show higher estrogenic activity, while the hexane extracts very low. The (xeno)estrogens from domestic wastewater could be removed obviously by activated sludge treatment units. However, the effluents of STWs in Nanjing still have chemical contaminants capable of binding to estrogen receptors.展开更多
Based on the principle of selective permeability of cell membrane,a new urban sewage treatment device and urban sewage recycling system are designed.The new urban sewage treatment device consists of 10 parts,namely:in...Based on the principle of selective permeability of cell membrane,a new urban sewage treatment device and urban sewage recycling system are designed.The new urban sewage treatment device consists of 10 parts,namely:inlet pipe,secondary filter screen,tertiary rectifier,gravity separation chamber,floating material collection chamber,sewage shunt pipes,cell membrane filtration chamber,cell membrane purification device,sediment collection chamber and purified water collection chamber.The urban sewage recycling system consists of 6 parts,namely:urban sewage collection device,filtration and sedimentation separation device,floating matter collection device,cell membrane sewage purification device,sediment collection device and urban water pool.展开更多
In this paper,from the three dimensions of development quality,sustainable development and public satisfaction,the index system of government performance evaluation of wastewater treatment in Beijing City was construc...In this paper,from the three dimensions of development quality,sustainable development and public satisfaction,the index system of government performance evaluation of wastewater treatment in Beijing City was constructed by conversion of critical success factor method.Using comprehensive evaluation method based on entropy weight method and principal component analysis method,the sewage treatment effect of Beijing municipal government from 2010 to 2017 was quantified,and the government s sewage treatment work was comprehensively evaluated.The evaluation results showed that the government has achieved remarkable results in sewage treatment,but it should continue to optimize the countermeasures in promoting the transformation and upgrading of economic structure,strengthening the management of urban sewage treatment and strict management system of water environment.展开更多
<span style="font-family:Verdana;">We are confronting a new threat in the prevalence of antibiotic-resistant bacteria followed by epidemic spread in aquatic environments in metropolitan areas because d...<span style="font-family:Verdana;">We are confronting a new threat in the prevalence of antibiotic-resistant bacteria followed by epidemic spread in aquatic environments in metropolitan areas because damage from river floods is increasing remarkably in Japan due to global extreme weather. The sewer penetration rate is about 100% in Tokyo and reclaimed water from sewage treatment plants accounts for over 50% of all water in both the down- and mid-stream areas of local rivers. The water quality of these rivers, which contain microflora, seems to be seriously affected by reclaimed water. In this study, we collected water samples on July 17, 2018 and examined the behavior of antibiotic-resistant fecal coliforms in the stream of a sewage treatment plant in Tokyo. Extended-spectrum </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-lactamase (ESBL)</span><span style="font-family:Verdana;">-producing fecal coliforms with encoding genes were found;the CTX-M-1, CTX-M-9, TEM, and SHV groups were found to have survived in the final effluent to the river after sterilization with sodium hypochlorite.展开更多
In recent years,the construction of rural sewage treatment in Beijing City has developed rapidly,but there are still many problems in some rural domestic sewage treatment. In this paper,the current situation of rural ...In recent years,the construction of rural sewage treatment in Beijing City has developed rapidly,but there are still many problems in some rural domestic sewage treatment. In this paper,the current situation of rural domestic sewage in Beijing City is combed,and its characteristics are summarized. Meanwhile,the current situation of rural domestic sewage treatment in Zhejiang Province,Hunan Province and Shandong Province is summarized by consulting relevant data. By comparing with current situation of rural domestic sewage treatment in Beijing City,it is found that there are some problems in the treatment of rural domestic sewage in Beijing City,such as unsuitable treatment mode,unreasonable discharge requirements and inadequate treatment technology. Therefore,some countermeasures and suggestions are proposed,such as strengthening the investigation,research and planning,and differential formulation of the sewage treatment discharge standards,and establishing modular treatment technology system. It is hoped that this paper will be helpful to the treatment of rural domestic sewage in Beijing City.展开更多
These days, water and wastewater treatment are one of the most important issues regarding to the human health. Wastewaters are one of the most environmental pollutants and a wide range of adverse effects linked to the...These days, water and wastewater treatment are one of the most important issues regarding to the human health. Wastewaters are one of the most environmental pollutants and a wide range of adverse effects linked to the effect of untreated wastewaters or wastewaters that treat improperly. The aim of this present study was to evaluate performance of the wastewater treatment plant at Al-Diwaniyah City according to the national standards. Therefore, data of the most common parameters (PH, BOD<sub>5</sub>, COD, TSS, PO<sub>4</sub>, NO<sub>3</sub>, Cl, and Oil and Grease) were collected from the wastewater treatment plant. The study revealed that the wastewater treatment plant was receiving medium to strong influent with a BOD<sub>5</sub>/COD ratio of between (0.4 - 0.7). Regression analysis was achieved to approximate the influent of BOD<sub>5</sub> and TSS. While the effluent quality was exceeded the Iraq standards for disposing treated wastewater to the water bodies with a fluctuation in the ratio of BOD5to COD as a consequence of the operational problems. Therefore, these results would be of help to planners and policy makers in the City to combat such this problem and to take the necessary actions to reduce the impact of these pollutants.展开更多
Taking a sewage treatment project of Dalian for example, this paper studied the feasibility and characteristics of two sewage treatment technologies, analyzed the process, operation management and energy consumption, ...Taking a sewage treatment project of Dalian for example, this paper studied the feasibility and characteristics of two sewage treatment technologies, analyzed the process, operation management and energy consumption, and determined the hydrolytic sedimentation tank - biological filter - V-Filter technology as the final solution of this project.展开更多
Rural sewage treatment is in need of more capital investment,in which the financing model of PPP(public-private partnership)is able to encourage the investment of social capital in this sector.Risk sharing is one of t...Rural sewage treatment is in need of more capital investment,in which the financing model of PPP(public-private partnership)is able to encourage the investment of social capital in this sector.Risk sharing is one of the core features in the PPP model.In view that the risk loss of projects cannot be accurately estimated,this article describes the uncertainty of risk loss with fuzzy numbers and allocates the distribution of risk loss among the participants of rural sewage treatment PPP projects with interval fuzzy Shapley value to ensure a more reasonable and effective risk distribution.展开更多
A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary...A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA River. We will gain a better understanding of the water quality in the LA River and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA River using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This data informs decisions regarding additional treatment or mitigation actions to safeguard downstream water quality and ecosystem health.展开更多
文摘Rural domestic sewage treatment is an important part of the rural revitalization strategy and a key action to build a livable, livable and beautiful countryside. This paper composes and summarizes the relevant studies on rural domestic sewage treatment from the governance techniques and modes of governance subjects and research perspectives, in order to provide reference for the implementation of rural revitalization strategy and rural domestic sewage treatment research and action implementation.
文摘[Objectives] By reasonable water distribution and air supply to soil, soil water permeability is maintained, and the nutrient conditions of degrading bacteria in soil are improved to effectively prevent soil clogging. [Methods] Through the innovation and improvement of traditional soil sewage treatment technology, the physical, chemical and biological characteristics of soil for sewage purification are utilized to enhance the pollutant decomposition ability of soil microorganisms and maintain soil water permeability.[Results] It has no secondary pollution, and can effectively remove pollutants such as COD_(Cr), TN, TP, NH_3-N, etc. in sewage. [Conclusions] The operation and maintenance cost is low, and the land can be reused, while water and nutrients can be restored to the land.
文摘With the development of rural economy, pollutions of rural sewage are in- creasingly serious. This paper introduces the characteristics of rural domestic sewage and the rural sewage treatment situation, and according to the problems of funds, management, process selection, policy and weak awareness of environmental protection in the rural domestic sewage treatment, puts forward relevant countermea- sures to ensure long-term operation of sewage treatment system, and achieve the purpose of improving rural water environment and protect the ecological environment in rural areas.
基金This work was supported by the National Natural Science Foundation of China (No. 50578153, 50525824, 20307010).
文摘Biotransformation of nonylphenol ethoxylates (NPEOs) during continuous anaerobic sewage treatment was compared with the aerobic treatment of sewage spiked with 23 μmol/L technical NPEOs over a period of 90 d. Immediate degradation of NPEOs was observed under both anaerobic and aerobic conditions, indicating that the enzymes and bacteria required for NPEO degradation existed abundantly in both aerobic and anaerobic sludge. Both treatments achieved high removal (〉 92%) of the spiked NPEO9 mixture. Liquid chromatography-mass spectrometry (LC-MS) analysis showed that short-chain NPEOs (NPEO1-NPEO3) accumulated in anaerobic (2.01-2.56 μmol/L) and aerobic (1.62-2.03 μmol/L) effluents, with nonylphenol (NP) (0.24-0.31 μmol/L) as another group of metabolites in the anaerobic effluent, and nonylphenoxy carboxylates (NPECs) (2.79-3.30 μmol/L) in the aerobic effluent. Significant accumulation of NP in the anaerobic sludge and NPEO1-3 in the sludge of two reactors was observed. These results indicated that it was difficult to control these harmful metabolites in the conventional treatment processes. Denaturing gradient gel electrophoresis profiles of sludge samples support the speculation that the NPEO degradation bacteria might be the dominant indigenous species.
基金Project(KJZD-M202000801) supported by the Major Project of Chongqing Municipal Education Commission,ChinaProject(2016YFE0205600) supported by the National Key Research&Development Program of China+1 种基金Project(CXQT19023) supported by the Chongqing University Innovation Group Project,ChinaProjects(KFJJ2018069,1853061,1856033) supported by the Key Platform Opening Project of Chongqing Technology and Business University,China。
文摘It is generally believed that intelligent management for sewage treatment plants(STPs) is essential to the sustainable engineering of future smart cities.The core of management lies in the precise prediction of daily volumes of sewage.The generation of sewage is the result of multiple factors from the whole social system.Characterized by strong process abstraction ability,data mining techniques have been viewed as promising prediction methods to realize intelligent STP management.However,existing data mining-based methods for this purpose just focus on a single factor such as an economical or meteorological factor and ignore their collaborative effects.To address this challenge,a deep learning-based intelligent management mechanism for STPs is proposed,to predict business volume.Specifically,the grey relation algorithm(GRA) and gated recursive unit network(GRU) are combined into a prediction model(GRAGRU).The GRA is utilized to select the factors that have a significant impact on the sewage business volume,and the GRU is set up to output the prediction results.We conducted a large number of experiments to verify the efficiency of the proposed GRA-GRU model.
文摘The problem of water pollution is one of the long-term difficulties in the process of rural environmental construction and economic development in China.In order to meet the requirements of the country’s green and sustainable development,many regions actively promote the construction of rural sewage treatment and fill in the shortcomings of the rural habitat environment to accelerate the construction of beautiful and livable villages.Through a lot of literature and case studies,this paper explores the environmental problems that are common in rural sewage treatment in the northern region of China,explores advanced domestic and foreign cases and technologies on this topic,and summarizes the landscape design strategies on this issue.From the perspective of ecological landscape design,the thesis seeks the theoretical and technical support for rural sewage treatment in river valley areas,and establishes a bridge between rural sewage treatment technology and ecological landscape.Finally,combining theory with practice,taking the project of Lushi sewage treatment in Sanmenxia as an example,team completed the landscape design of ecological sewage purification display area in Zhangjiacun.The design focuses on presenting the application of internal sewage treatment technology and external landscape aesthetics.According to the main points of ecological landscape design and the theory of ecological edge effect,the local ecological system is effectively protected,and a rural domestic sewage purification display area with economic benefits is constructed.
基金supported by the GEF/UNDP Second National Communication on Climate Change of China--China’s inventory of GHG emissions from wastewater/sewage treatment subproject
文摘Based on the statistics from the China Statistical Yearbook (2000-2009) on environment and methods recommended by the IPCC, the amounts of greenhouse gas (GHG) emissions from domestic and industrial sewage treatment in China are estimated for the period of 2003-2009. CO2 emissions per capita from sewage treatment plants are also analyzed. The results show that the GHG emissions from sewage treatment plants increased steadily from 2003 to 2009; N20 emissions from domestic sewage are the major source of the total GHG emissions from domestic sewage; CH4 emissions from domestic sewage increase with the greatest speed; CH4 emissions from paper and pulp industry are the major source of industrial sewage emissions; CO2 emissions per capita increase constantly from 2003 to 2009.
文摘Existing problems of sewage treatment plants in small towns were summarized firstly,and then the developing trend of construction of sewage treatment plants in small towns was discussed from the aspects of project decision,site selection,design,processing technology and construction financing models. Finally,outlooks for its future development were proposed to provide reference for the construction of sewage treatment plants in small towns in future.
文摘[Objective] The research aimed to study influence factors of phosphorus removal by chemical method in sewage treatment system. [ Method] In different reaction systems, removal effect of the phosphorus in sewage by dosing lime and influence of the constraint factor were stud- ied. [ Result] Lime precipitation method treating high-concentration phosphorus wastewater could not only decline cost of phosphorus removal by chemical method, but also reach better treatment effect under suitable stirring and precipitation conditions by controlling alkalinity and pH. Phosphor- us content of chemical sludge after treatment could reach 9% -12%, with higher recyclable value. E Conclusion] Lime method treating phosphorus- rich sewage was more economic than low-concentration phosphorus sewage, and had very great potential for recycling phosphorus.
基金Supported by Project of National Natural Science Foundation of China(42007317)Project of Guangdong Basic and Applied Basic Research Foundation(2019A1515110272)+1 种基金Outstanding Young Teachers'Scientific Research Ability Improvement Program Funding Project of Zhaoqing University(YQ202105)Innovation and Entrepreneurship Training Program for College Students(202210580015).
文摘Microplastic pollution has become a worldwide issue.The discharge of sewage treatment plants(STPs)or wastewater treatment plant(WWTPs)is an important way for microplastics to enter the environment.This study reviewed the sources and occurrence characteristics(type,size,color and components)of microplastics in domestic and foreign sewage plants.It elaborated the removal principles of microplastics by primary,secondary and tertiary treatments.In addition,the removal effects of various treatment units and different processes on microplastics were summarized.In the future,the removal mechanism of microplastics in sewage treatment plants should be discussed in more depth,so as to further improve the removal rate of microplastics by optimizing and transforming traditional sewage treatment processes.Therefore,it is necessary to develop new technologies/processes specifically for the removal of microplastics and promote them to practical applications.
基金Funded by the National Natural Science Foundation of China (No.59838300)
文摘Daily influent quantity forecasting plays an important role in sewage treatment plant design and operation. Its uncertain factors are classified into three categories including day types, weather conditions and special events, of which the latter two are considered with a BP (Back Propagation) model. On this basis, the daily period feature is taken into account in the presented model. The data from a practical sewage treatment plant utility is employed to show the effectiveness of the method.
基金Program for New Century Excellent Talents in University of China(No.05-0481)
文摘The estrogenic activity of influents and effluents of five municipal sewage treatment works (STWs) in Nanjing was investigated. The water samples were enriched by solid phase extraction, then eluted with different polar solvents, and f'mally three fractionated extracts were obtained. Estrogen receptor recombinant yeast screen was used to evaluate the estrogenic activity of individual fractionated extracts and their mixture. The results show that the influents and effluents of the two STWs mainly receiving industrial wastewater have no obvious estrogenic activity, and the water samples from the other three STWs mainly receiving domestic wastewater show different degrees of estrogenic activity. The total estrogenic concentration ranged from 171. 52 ng/L EEQ (E2 - equivalent concentration) to 1 008.37 ng/L EEQ in the influents, and from ND (not detected) to 36.3 ng/L EEQ in the effluents. By comparing the results of different fractionated extracts, the methanol and dichloromethane extracts of the water samples show higher estrogenic activity, while the hexane extracts very low. The (xeno)estrogens from domestic wastewater could be removed obviously by activated sludge treatment units. However, the effluents of STWs in Nanjing still have chemical contaminants capable of binding to estrogen receptors.
基金Supported by Undergraduate Innovation and Enterpreneurship Training Program of Dalian University(202111258202).
文摘Based on the principle of selective permeability of cell membrane,a new urban sewage treatment device and urban sewage recycling system are designed.The new urban sewage treatment device consists of 10 parts,namely:inlet pipe,secondary filter screen,tertiary rectifier,gravity separation chamber,floating material collection chamber,sewage shunt pipes,cell membrane filtration chamber,cell membrane purification device,sediment collection chamber and purified water collection chamber.The urban sewage recycling system consists of 6 parts,namely:urban sewage collection device,filtration and sedimentation separation device,floating matter collection device,cell membrane sewage purification device,sediment collection device and urban water pool.
基金Supported by the Collaborative Innovation Project of Chaoyang District(cyxc1819).
文摘In this paper,from the three dimensions of development quality,sustainable development and public satisfaction,the index system of government performance evaluation of wastewater treatment in Beijing City was constructed by conversion of critical success factor method.Using comprehensive evaluation method based on entropy weight method and principal component analysis method,the sewage treatment effect of Beijing municipal government from 2010 to 2017 was quantified,and the government s sewage treatment work was comprehensively evaluated.The evaluation results showed that the government has achieved remarkable results in sewage treatment,but it should continue to optimize the countermeasures in promoting the transformation and upgrading of economic structure,strengthening the management of urban sewage treatment and strict management system of water environment.
文摘<span style="font-family:Verdana;">We are confronting a new threat in the prevalence of antibiotic-resistant bacteria followed by epidemic spread in aquatic environments in metropolitan areas because damage from river floods is increasing remarkably in Japan due to global extreme weather. The sewer penetration rate is about 100% in Tokyo and reclaimed water from sewage treatment plants accounts for over 50% of all water in both the down- and mid-stream areas of local rivers. The water quality of these rivers, which contain microflora, seems to be seriously affected by reclaimed water. In this study, we collected water samples on July 17, 2018 and examined the behavior of antibiotic-resistant fecal coliforms in the stream of a sewage treatment plant in Tokyo. Extended-spectrum </span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">-lactamase (ESBL)</span><span style="font-family:Verdana;">-producing fecal coliforms with encoding genes were found;the CTX-M-1, CTX-M-9, TEM, and SHV groups were found to have survived in the final effluent to the river after sterilization with sodium hypochlorite.
基金Supported by the Collaborative Innovation Project of Chaoyang District。
文摘In recent years,the construction of rural sewage treatment in Beijing City has developed rapidly,but there are still many problems in some rural domestic sewage treatment. In this paper,the current situation of rural domestic sewage in Beijing City is combed,and its characteristics are summarized. Meanwhile,the current situation of rural domestic sewage treatment in Zhejiang Province,Hunan Province and Shandong Province is summarized by consulting relevant data. By comparing with current situation of rural domestic sewage treatment in Beijing City,it is found that there are some problems in the treatment of rural domestic sewage in Beijing City,such as unsuitable treatment mode,unreasonable discharge requirements and inadequate treatment technology. Therefore,some countermeasures and suggestions are proposed,such as strengthening the investigation,research and planning,and differential formulation of the sewage treatment discharge standards,and establishing modular treatment technology system. It is hoped that this paper will be helpful to the treatment of rural domestic sewage in Beijing City.
文摘These days, water and wastewater treatment are one of the most important issues regarding to the human health. Wastewaters are one of the most environmental pollutants and a wide range of adverse effects linked to the effect of untreated wastewaters or wastewaters that treat improperly. The aim of this present study was to evaluate performance of the wastewater treatment plant at Al-Diwaniyah City according to the national standards. Therefore, data of the most common parameters (PH, BOD<sub>5</sub>, COD, TSS, PO<sub>4</sub>, NO<sub>3</sub>, Cl, and Oil and Grease) were collected from the wastewater treatment plant. The study revealed that the wastewater treatment plant was receiving medium to strong influent with a BOD<sub>5</sub>/COD ratio of between (0.4 - 0.7). Regression analysis was achieved to approximate the influent of BOD<sub>5</sub> and TSS. While the effluent quality was exceeded the Iraq standards for disposing treated wastewater to the water bodies with a fluctuation in the ratio of BOD5to COD as a consequence of the operational problems. Therefore, these results would be of help to planners and policy makers in the City to combat such this problem and to take the necessary actions to reduce the impact of these pollutants.
文摘Taking a sewage treatment project of Dalian for example, this paper studied the feasibility and characteristics of two sewage treatment technologies, analyzed the process, operation management and energy consumption, and determined the hydrolytic sedimentation tank - biological filter - V-Filter technology as the final solution of this project.
文摘Rural sewage treatment is in need of more capital investment,in which the financing model of PPP(public-private partnership)is able to encourage the investment of social capital in this sector.Risk sharing is one of the core features in the PPP model.In view that the risk loss of projects cannot be accurately estimated,this article describes the uncertainty of risk loss with fuzzy numbers and allocates the distribution of risk loss among the participants of rural sewage treatment PPP projects with interval fuzzy Shapley value to ensure a more reasonable and effective risk distribution.
文摘A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA River. We will gain a better understanding of the water quality in the LA River and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA River using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This data informs decisions regarding additional treatment or mitigation actions to safeguard downstream water quality and ecosystem health.