A newly developed model for the optimum municipal wastewater treatment plant(MWTP) design is presented. Through introducing the interval variables, the model attempts to consider the effects of uncertainties caused by...A newly developed model for the optimum municipal wastewater treatment plant(MWTP) design is presented. Through introducing the interval variables, the model attempts to consider the effects of uncertainties caused by the fluctuation of the wastewater quality and quantity during the design of MWTP. The model solution procedure is illustrated in detail, and a numerical example is given to verify the feasibility and advantage of the model. Furthermore, the possibility of the model application is briefly outlined.展开更多
Wastewater treatment is an important source of greenhouse gases(GHGs).Yet large uncertainties remain in the quantification of GHG emissions from municipal wastewater treatment plants(MWWTPs)in China.A high-resolution ...Wastewater treatment is an important source of greenhouse gases(GHGs).Yet large uncertainties remain in the quantification of GHG emissions from municipal wastewater treatment plants(MWWTPs)in China.A high-resolution and technology-specific emission inventory is still lacking to support mitigation strategies of MWWTPs.Here we develop a plant-level and technology-based MWWTP emission inventory for China covering 8703 plants and 19 treatment technology categories by compiling and harmonizing the most up-to-date facility-level databases.China's methane(CH_(4))and nitrous oxide(N_(2)O)emissions from MWWTPs in 2020 are estimated to be 150.6 Gg and 22.0 Gg,respectively,with the uncertainty range of-30%to 37%and-30%to 26%at 95%confidence interval.We find an emission inequality across cities,with the richest cities emitting two times more CH_(4)and N_(2)O per capita from municipal wastewater treatment than the poorest cities.The emitted CH_(4)and N_(2)O are dominated by Anaerobic/Anoxic/Oxic-,Sequencing Batch Reactor-,Oxidation Ditch-,and Anoxic/Oxic-based MWWTPs of less than 20 years old.Considering the relatively young age structure of China's MWWTPs,the committed emissions highlight the importance of reducing on-site GHG emissions by optimization of operating conditions and innovation management.The emission differences among our estimates,previous studies,and the Intergovernmental Panel on Climate Change guidelines are largely attributed to the uncertainties in emission factors,implying the urgent need for more plant-integrated measurements to improve the accuracy of emission accounting.展开更多
Microplastics(MPs)and plasticizers,such as phthalate esters(PAEs),were frequently detected in municipal wastewater treatment plants(MWTP).Previous research mainly studied the removal of MPs and PAEs in wastewater.Howe...Microplastics(MPs)and plasticizers,such as phthalate esters(PAEs),were frequently detected in municipal wastewater treatment plants(MWTP).Previous research mainly studied the removal of MPs and PAEs in wastewater.However,the occurrence of MPs and PAEs in the sludge was generally ignored.To comprehensively investigate the occurrence and the migration behaviors of MPs and PAEs in MWTP,a series of representative parameters including the number,size,color,shape of MPs,and the concentrations of PAEs in wastewater and sludge were systematically investigated.In this study,the concentrations of MPs in the influent and effluent were 15.46±0.37 and 0.30±0.14 particles/L.The MP removal efficiency of 98.1%was achieved and about 73.8%of MPs were accumulated in the sludge in the MWTP.The numbers of MPs in the sludge before and after digestion were 4.40±0.14 and 0.31±0.01 particles/g(dry sludge),respectively.Fourier Transform Infrared Spectroscopy(ATR FT-IR)analysis showed that the main types of MPs were polyethylene terephthalate(PET),polypropylene(PP),polyethylene(PE),and polystyrene(PS).Six PAEs,including phthalate(DMP),diethyl phthalate(DEP),diisobutyl phthalate(DIBP),ortho dibutyl phthalate(DBP),butyl benzyl phthalate(BBP),and bis(2-ethyl)hexyl phthalate(DEHP),were detected in the MWTP.The concentrations of total PAEs(ΣPAEs)in the influent and effluent were 76.66 and 6.28μg/L,respectively.The concentrations ofΣPAEs in the sludge before and after digestion were 152.64 and 31.70μg/g,respectively.In the process of thermal hydrolysis,the number and size of MPs decreased accompanied by the increase of the plasticizer concentration.展开更多
Municipal wastewater consists of a downstream collection of flushed sewage(without solid waste),other household runoffs,industrial runoffs,hospital runoffs and agricultural runoffs through an underground pipe before t...Municipal wastewater consists of a downstream collection of flushed sewage(without solid waste),other household runoffs,industrial runoffs,hospital runoffs and agricultural runoffs through an underground pipe before treatment.A runoff collection system called the wastewater treatment plant(WWTPs)treats such wastewater before release into environment following specific regulatory standards.This years-long practice has been improved upon by adding end-to-end pipe technologies with a view to enhancing the quality of effluent released.However,effluents released into the environment from design/application of WWTPs appear to contain emerging contaminants of both biotic and abiotic nature.The observation of chemical contaminants,antibiotic resistant bacteria(ARB),antibiotic resistant genes(ARGs)and diverse pathogenic bacteria genera in wastewater works release further affirm the abundance of such emerging contaminants.As a result,the government and water regulatory organizations in various part of the world are considering the removal of water reuse act from recycling policy/process.Current global debate is focused on questions about sustenance of any improved additional treatment level;effect of energy consumption by added treatment stage and its impact on the environmental wellness as contaminants borne wastewater is consistently released.Technological advancement/research suggests implementation of newer innovative infrastructural systems(NIIS)such as Mobbing Bed Biofilm Rector(MBBR),for wastewater effluent management which involve addition of newer wastewater treatment stages.This review addressed current pitfalls including wastewater microbiota of high epidemiological/public health relevance and affirms the need for such improvement which requires modification of ongoing institutional framework with a view to encourage implementation of NIIS for an improved effluent release.Exploiting the advances of microbial biofilming and the potentials of microbial biofueling as discussed in various section promises a future of robust environmental system,stable operational standard,release of quality effluent and sustainable management of wastewater works.Application of the aforementioned would enhance qualityWWTPs release and in-defacto reduces spread of ARB/ARGs as well as impacts both the environment wellness and public health.展开更多
针对城市污水处理厂运行过程中产生微生物气溶胶,工作人员暴露于气溶胶环境可经呼吸摄入致病性微生物,最终造成健康寿命损失的问题,通过对污水处理厂空气中气溶胶颗粒及其携载的病原体进行定量识别,明确工作人员的职业暴露风险,进一步...针对城市污水处理厂运行过程中产生微生物气溶胶,工作人员暴露于气溶胶环境可经呼吸摄入致病性微生物,最终造成健康寿命损失的问题,通过对污水处理厂空气中气溶胶颗粒及其携载的病原体进行定量识别,明确工作人员的职业暴露风险,进一步结合微生物定量风险评估及疾病负担研究方法,以伤残寿命(disability adjusted life year, DALY)为健康评价指标,提出基于DALY的微生物气溶胶职业健康风险评估新模式及计算方法体系,并进一步遴选典型病原体进行疾病负担计算。结果表明:典型污水处理厂工作人员职业暴露过程中,经气溶胶摄入诺如病毒、腺病毒和轮状病毒造成的健康损失均明显高出WHO标准,需改进工艺或限制接触。展开更多
文摘A newly developed model for the optimum municipal wastewater treatment plant(MWTP) design is presented. Through introducing the interval variables, the model attempts to consider the effects of uncertainties caused by the fluctuation of the wastewater quality and quantity during the design of MWTP. The model solution procedure is illustrated in detail, and a numerical example is given to verify the feasibility and advantage of the model. Furthermore, the possibility of the model application is briefly outlined.
基金supported by the Shenzhen Science and Technology Innovation Commission(No.RCBS20210609103731062,No.WDZC20220810110301001)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515110887)H.L.acknowledge additional support from the Shenzhen Overseas High-Level Talent Project.
文摘Wastewater treatment is an important source of greenhouse gases(GHGs).Yet large uncertainties remain in the quantification of GHG emissions from municipal wastewater treatment plants(MWWTPs)in China.A high-resolution and technology-specific emission inventory is still lacking to support mitigation strategies of MWWTPs.Here we develop a plant-level and technology-based MWWTP emission inventory for China covering 8703 plants and 19 treatment technology categories by compiling and harmonizing the most up-to-date facility-level databases.China's methane(CH_(4))and nitrous oxide(N_(2)O)emissions from MWWTPs in 2020 are estimated to be 150.6 Gg and 22.0 Gg,respectively,with the uncertainty range of-30%to 37%and-30%to 26%at 95%confidence interval.We find an emission inequality across cities,with the richest cities emitting two times more CH_(4)and N_(2)O per capita from municipal wastewater treatment than the poorest cities.The emitted CH_(4)and N_(2)O are dominated by Anaerobic/Anoxic/Oxic-,Sequencing Batch Reactor-,Oxidation Ditch-,and Anoxic/Oxic-based MWWTPs of less than 20 years old.Considering the relatively young age structure of China's MWWTPs,the committed emissions highlight the importance of reducing on-site GHG emissions by optimization of operating conditions and innovation management.The emission differences among our estimates,previous studies,and the Intergovernmental Panel on Climate Change guidelines are largely attributed to the uncertainties in emission factors,implying the urgent need for more plant-integrated measurements to improve the accuracy of emission accounting.
基金supported by the National Natural Science Foundation of China(Nos.42177051 and 52170021).
文摘Microplastics(MPs)and plasticizers,such as phthalate esters(PAEs),were frequently detected in municipal wastewater treatment plants(MWTP).Previous research mainly studied the removal of MPs and PAEs in wastewater.However,the occurrence of MPs and PAEs in the sludge was generally ignored.To comprehensively investigate the occurrence and the migration behaviors of MPs and PAEs in MWTP,a series of representative parameters including the number,size,color,shape of MPs,and the concentrations of PAEs in wastewater and sludge were systematically investigated.In this study,the concentrations of MPs in the influent and effluent were 15.46±0.37 and 0.30±0.14 particles/L.The MP removal efficiency of 98.1%was achieved and about 73.8%of MPs were accumulated in the sludge in the MWTP.The numbers of MPs in the sludge before and after digestion were 4.40±0.14 and 0.31±0.01 particles/g(dry sludge),respectively.Fourier Transform Infrared Spectroscopy(ATR FT-IR)analysis showed that the main types of MPs were polyethylene terephthalate(PET),polypropylene(PP),polyethylene(PE),and polystyrene(PS).Six PAEs,including phthalate(DMP),diethyl phthalate(DEP),diisobutyl phthalate(DIBP),ortho dibutyl phthalate(DBP),butyl benzyl phthalate(BBP),and bis(2-ethyl)hexyl phthalate(DEHP),were detected in the MWTP.The concentrations of total PAEs(ΣPAEs)in the influent and effluent were 76.66 and 6.28μg/L,respectively.The concentrations ofΣPAEs in the sludge before and after digestion were 152.64 and 31.70μg/g,respectively.In the process of thermal hydrolysis,the number and size of MPs decreased accompanied by the increase of the plasticizer concentration.
文摘Municipal wastewater consists of a downstream collection of flushed sewage(without solid waste),other household runoffs,industrial runoffs,hospital runoffs and agricultural runoffs through an underground pipe before treatment.A runoff collection system called the wastewater treatment plant(WWTPs)treats such wastewater before release into environment following specific regulatory standards.This years-long practice has been improved upon by adding end-to-end pipe technologies with a view to enhancing the quality of effluent released.However,effluents released into the environment from design/application of WWTPs appear to contain emerging contaminants of both biotic and abiotic nature.The observation of chemical contaminants,antibiotic resistant bacteria(ARB),antibiotic resistant genes(ARGs)and diverse pathogenic bacteria genera in wastewater works release further affirm the abundance of such emerging contaminants.As a result,the government and water regulatory organizations in various part of the world are considering the removal of water reuse act from recycling policy/process.Current global debate is focused on questions about sustenance of any improved additional treatment level;effect of energy consumption by added treatment stage and its impact on the environmental wellness as contaminants borne wastewater is consistently released.Technological advancement/research suggests implementation of newer innovative infrastructural systems(NIIS)such as Mobbing Bed Biofilm Rector(MBBR),for wastewater effluent management which involve addition of newer wastewater treatment stages.This review addressed current pitfalls including wastewater microbiota of high epidemiological/public health relevance and affirms the need for such improvement which requires modification of ongoing institutional framework with a view to encourage implementation of NIIS for an improved effluent release.Exploiting the advances of microbial biofilming and the potentials of microbial biofueling as discussed in various section promises a future of robust environmental system,stable operational standard,release of quality effluent and sustainable management of wastewater works.Application of the aforementioned would enhance qualityWWTPs release and in-defacto reduces spread of ARB/ARGs as well as impacts both the environment wellness and public health.
文摘针对城市污水处理厂运行过程中产生微生物气溶胶,工作人员暴露于气溶胶环境可经呼吸摄入致病性微生物,最终造成健康寿命损失的问题,通过对污水处理厂空气中气溶胶颗粒及其携载的病原体进行定量识别,明确工作人员的职业暴露风险,进一步结合微生物定量风险评估及疾病负担研究方法,以伤残寿命(disability adjusted life year, DALY)为健康评价指标,提出基于DALY的微生物气溶胶职业健康风险评估新模式及计算方法体系,并进一步遴选典型病原体进行疾病负担计算。结果表明:典型污水处理厂工作人员职业暴露过程中,经气溶胶摄入诺如病毒、腺病毒和轮状病毒造成的健康损失均明显高出WHO标准,需改进工艺或限制接触。
