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
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
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 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.