Endocrine disrupting chemicals(EDCs) in the secondary effluent discharged from wastewater treatment plants are of great concern when water reuse is intended. Ozonation and ultrafiltration(UF) are powerful technologies...Endocrine disrupting chemicals(EDCs) in the secondary effluent discharged from wastewater treatment plants are of great concern when water reuse is intended. Ozonation and ultrafiltration(UF) are powerful technologies reported to eliminate EDCs. Due to the importance of effluent organic matters(EfOMs) in secondary effluent, the effects of three kinds of EfOM on the treatment of five EDCs using ozonation and UF were investigated. The three kinds of EfOM studied were humic acid sodium salt(NaAH), bovine serum albumin(BSA)and sodium alginate(NaAg); and the five EDCs were estrone, 17β-estradiol, estriol, 17α-ethynyl estradiol and bisphenol A. The results showed that EfOM accelerated the decay rate of ozone and inhibited the degradation efficiency of EDCs by ozonation in the order NaAH > BSA > NaAg.The ultraviolet absorbance at 280 nm(UVA_(280)) has potential for use as a surrogate indicator to assess EDC removal via ozonation without conducting difficult EDC analyses. When the decline in UVA_(280) exceeded 18%, the five EDCs had been completely removed. The UF behavior of NaAH,BSA and NaAg was found to follow the cake filtration law. The fouling potential of EfOM followed the order NaAg > NaAH > BSA; while EfOM on the membrane surface enhanced EDC removal in the order NaAH > BSA > NaAg. The mean retention rate of the membrane was increased by 24%, 10% and 8%, respectively. The properties of EDCs and EfOM cakes both influenced the EDC removal rates due to adsorption, size exclusion and charge attraction.展开更多
Municipal wastewater reclamation is becoming of increasing importance in the world to solve the problem of water scarcity. A better understanding of the molecular composition of effluent organic matter(Ef OM) in the...Municipal wastewater reclamation is becoming of increasing importance in the world to solve the problem of water scarcity. A better understanding of the molecular composition of effluent organic matter(Ef OM) in the treated effluents of municipal wastewater treatment plants(WWTPs) is crucial for ensuring the safety of water reuse. In this study, the molecular composition of Ef OM in the secondary effluent of a WWTP in Beijing and the reclaimed water further treated with a coagulation–sedimentation–ozonation process were characterized using a non-target Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS) method and compared to that of natural organic matter(NOM) in the local source water from a reservoir. It was found that the molecular composition of Ef OM in the secondary effluent and reclaimed water was dominated by CHOS formulas, while NOM in the source water was dominated by CHO formulas. The CHO formulas of the three samples had similar origins. Anthropogenic surfactants were responsible for the CHOS formulas in Ef OM of the secondary effluent and were not well removed by the coagulation-sedimentation-ozonation treatment process adopted.展开更多
Sulfamethoxazole(SMX)is commonly detected in wastewater and cannot be completely decomposed during conventional treatment processes.Ozone(O_(3))is often used in water treatment.This study explored the influence of nat...Sulfamethoxazole(SMX)is commonly detected in wastewater and cannot be completely decomposed during conventional treatment processes.Ozone(O_(3))is often used in water treatment.This study explored the influence of natural organic matters(NOM)in secondary effluent of a sewage treatment plant on the ozonation pathways of SMX.The changes in NOM components during ozonation were also analyzed.SMX was primarily degraded by hydrolysis,isoxazole-ring opening,and double-bond addition,whereas hydroxylation was not the principal route given the low maximum abundances of the hydroxylated products,with m/z of 269 and 287.The hydroxylation process occurred mainly through indirect oxidation because the maximum abundances of the products reduced by about 70%after the radical quencher was added,whereas isoxazole-ring opening and double-bond addition processes mainly depended on direct oxidation,which was unaffected by the quencher.NOM mainly affected the degradation of micropollutants by consuming•OH rather than O_(3)molecules,resulting in the 63%–85%decrease in indirect oxidation products.The NOM in the effluent were also degraded simultaneously during ozonation,and the components with larger aromaticity were more likely degraded through direct oxidation.The dependences of the three main components of NOM in the effluent on indirect oxidation followed the sequence:humic-like substances>fluvic-like substance-s>protein-like substances.This study reveals the ozonation mechanism of SMX in secondary effluent and provides a theoretical basis for the control of SMX and its degradation products in actual water treatment.展开更多
The characteristics of effluent organic matter(EfOM) from a wastewater treatment plant(WWTP) during ozonation were investigated using excitation and emission matrix(EEM)spectra, Fourier transform infrared spectroscopy...The characteristics of effluent organic matter(EfOM) from a wastewater treatment plant(WWTP) during ozonation were investigated using excitation and emission matrix(EEM)spectra, Fourier transform infrared spectroscopy(FT-IR) and high-performance size exclusion chromatography(HPSEC) at different ozone dosages. The selectivity of ozonation towards different constituents and functional groups was analysed using two-dimensional correlation spectra(2D-COS) probed by FT-IR, synchronous fluorescence spectra and HPSEC.The results indicated that ozonation can destroy aromatic structures of EfOM and change its molecular weight distribution(MWD). According to 2D-COS analysis, microbial humiclike substances were preferentially removed, and then the protein-like fractions. Terrestrial humic-like components exhibited inactivity towards ozonation compared with the above two fractions. Protein-like substances with small molecular weight were preferentially reacted during ozonation based on 2D-COS probed by HPSEC. In addition, the selectivity of ozone towards different functional groups of EfOM exhibited the following sequence:phenolic and alcoholic C\O groups > aromatic structures containing C_C double bonds >aliphatic C\H. X-ray photoelectron spectroscopy(XPS) further elucidated the preferential reaction of aromatic structures in EfOM during ozonation.展开更多
以城市污水厂二级出水为研究对象,利用大孔吸附树脂将污水中溶解性有机物(Dissolved organic matter,DOM)分离成疏水酸性、中性、碱性物质和亲水性物质等4个组分,同时分析了各组分的有机物特性.结果表明,二级出水溶解性有机物中疏水酸...以城市污水厂二级出水为研究对象,利用大孔吸附树脂将污水中溶解性有机物(Dissolved organic matter,DOM)分离成疏水酸性、中性、碱性物质和亲水性物质等4个组分,同时分析了各组分的有机物特性.结果表明,二级出水溶解性有机物中疏水酸性物质是二级出水溶解性有机物的主要组成部分.4种组分中均含有腐殖质类物质,疏水酸性物质(Hydrophobic acids,HOA)和疏水中性物质(Hydrophobic neutrals,HON)中腐殖酸类峰的荧光强度较大,亲水性物质(Hydrophilic fraction,HI)中的蛋白峰荧光强度较大.腐殖质类物质分子量分布较为单一,主要分布在0.9 k Da左右,而疏水性组分蛋白类物质分子量分布较为广泛,在200 k Da左右及小于9 k Da时均有一定分布,亲水性组分蛋白类物质主要由分子量小于9 k Da的物质组成.X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)分析结果表明,HOA、HON中含有较多的芳香族化合物,而疏水碱性物质(Hydrophobic bases,HOB)、HI中则含有较多的羰基和羧基类官能团.展开更多
基金supported by the National Natural Science Foundation of China (No.51808008)the Natural Science Foundation of Hebei Province (No.E2017409004)the Youth Foundation of Hebei Province Education Department (No.QN2016224)
文摘Endocrine disrupting chemicals(EDCs) in the secondary effluent discharged from wastewater treatment plants are of great concern when water reuse is intended. Ozonation and ultrafiltration(UF) are powerful technologies reported to eliminate EDCs. Due to the importance of effluent organic matters(EfOMs) in secondary effluent, the effects of three kinds of EfOM on the treatment of five EDCs using ozonation and UF were investigated. The three kinds of EfOM studied were humic acid sodium salt(NaAH), bovine serum albumin(BSA)and sodium alginate(NaAg); and the five EDCs were estrone, 17β-estradiol, estriol, 17α-ethynyl estradiol and bisphenol A. The results showed that EfOM accelerated the decay rate of ozone and inhibited the degradation efficiency of EDCs by ozonation in the order NaAH > BSA > NaAg.The ultraviolet absorbance at 280 nm(UVA_(280)) has potential for use as a surrogate indicator to assess EDC removal via ozonation without conducting difficult EDC analyses. When the decline in UVA_(280) exceeded 18%, the five EDCs had been completely removed. The UF behavior of NaAH,BSA and NaAg was found to follow the cake filtration law. The fouling potential of EfOM followed the order NaAg > NaAH > BSA; while EfOM on the membrane surface enhanced EDC removal in the order NaAH > BSA > NaAg. The mean retention rate of the membrane was increased by 24%, 10% and 8%, respectively. The properties of EDCs and EfOM cakes both influenced the EDC removal rates due to adsorption, size exclusion and charge attraction.
基金supported by the National Natural Science Foundation of China(Nos.21377150 and 51578530)
文摘Municipal wastewater reclamation is becoming of increasing importance in the world to solve the problem of water scarcity. A better understanding of the molecular composition of effluent organic matter(Ef OM) in the treated effluents of municipal wastewater treatment plants(WWTPs) is crucial for ensuring the safety of water reuse. In this study, the molecular composition of Ef OM in the secondary effluent of a WWTP in Beijing and the reclaimed water further treated with a coagulation–sedimentation–ozonation process were characterized using a non-target Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS) method and compared to that of natural organic matter(NOM) in the local source water from a reservoir. It was found that the molecular composition of Ef OM in the secondary effluent and reclaimed water was dominated by CHOS formulas, while NOM in the source water was dominated by CHO formulas. The CHO formulas of the three samples had similar origins. Anthropogenic surfactants were responsible for the CHOS formulas in Ef OM of the secondary effluent and were not well removed by the coagulation-sedimentation-ozonation treatment process adopted.
基金This work was supported by the National Key Research and Development Project(No.2019YFD1100204).The experimental supporting by National Environmental and Energy Base for International Science&Technology Cooperation was greatly appreciated.
文摘Sulfamethoxazole(SMX)is commonly detected in wastewater and cannot be completely decomposed during conventional treatment processes.Ozone(O_(3))is often used in water treatment.This study explored the influence of natural organic matters(NOM)in secondary effluent of a sewage treatment plant on the ozonation pathways of SMX.The changes in NOM components during ozonation were also analyzed.SMX was primarily degraded by hydrolysis,isoxazole-ring opening,and double-bond addition,whereas hydroxylation was not the principal route given the low maximum abundances of the hydroxylated products,with m/z of 269 and 287.The hydroxylation process occurred mainly through indirect oxidation because the maximum abundances of the products reduced by about 70%after the radical quencher was added,whereas isoxazole-ring opening and double-bond addition processes mainly depended on direct oxidation,which was unaffected by the quencher.NOM mainly affected the degradation of micropollutants by consuming•OH rather than O_(3)molecules,resulting in the 63%–85%decrease in indirect oxidation products.The NOM in the effluent were also degraded simultaneously during ozonation,and the components with larger aromaticity were more likely degraded through direct oxidation.The dependences of the three main components of NOM in the effluent on indirect oxidation followed the sequence:humic-like substances>fluvic-like substance-s>protein-like substances.This study reveals the ozonation mechanism of SMX in secondary effluent and provides a theoretical basis for the control of SMX and its degradation products in actual water treatment.
基金supported by the National Key Technology Support Program (No.2014BAC13B06)the National Natural Science Foundation of China (Nos.51708443,51378414)+2 种基金the National Key Research and Development Program of China (No.2016YFC0400701)the China Postdoctoral Science Foundation (No.2017M623326XB)the Program for Innovative Research Teams in Shaanxi (No.2013KCT-13)
文摘The characteristics of effluent organic matter(EfOM) from a wastewater treatment plant(WWTP) during ozonation were investigated using excitation and emission matrix(EEM)spectra, Fourier transform infrared spectroscopy(FT-IR) and high-performance size exclusion chromatography(HPSEC) at different ozone dosages. The selectivity of ozonation towards different constituents and functional groups was analysed using two-dimensional correlation spectra(2D-COS) probed by FT-IR, synchronous fluorescence spectra and HPSEC.The results indicated that ozonation can destroy aromatic structures of EfOM and change its molecular weight distribution(MWD). According to 2D-COS analysis, microbial humiclike substances were preferentially removed, and then the protein-like fractions. Terrestrial humic-like components exhibited inactivity towards ozonation compared with the above two fractions. Protein-like substances with small molecular weight were preferentially reacted during ozonation based on 2D-COS probed by HPSEC. In addition, the selectivity of ozone towards different functional groups of EfOM exhibited the following sequence:phenolic and alcoholic C\O groups > aromatic structures containing C_C double bonds >aliphatic C\H. X-ray photoelectron spectroscopy(XPS) further elucidated the preferential reaction of aromatic structures in EfOM during ozonation.
文摘以城市污水厂二级出水为研究对象,利用大孔吸附树脂将污水中溶解性有机物(Dissolved organic matter,DOM)分离成疏水酸性、中性、碱性物质和亲水性物质等4个组分,同时分析了各组分的有机物特性.结果表明,二级出水溶解性有机物中疏水酸性物质是二级出水溶解性有机物的主要组成部分.4种组分中均含有腐殖质类物质,疏水酸性物质(Hydrophobic acids,HOA)和疏水中性物质(Hydrophobic neutrals,HON)中腐殖酸类峰的荧光强度较大,亲水性物质(Hydrophilic fraction,HI)中的蛋白峰荧光强度较大.腐殖质类物质分子量分布较为单一,主要分布在0.9 k Da左右,而疏水性组分蛋白类物质分子量分布较为广泛,在200 k Da左右及小于9 k Da时均有一定分布,亲水性组分蛋白类物质主要由分子量小于9 k Da的物质组成.X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)分析结果表明,HOA、HON中含有较多的芳香族化合物,而疏水碱性物质(Hydrophobic bases,HOB)、HI中则含有较多的羰基和羧基类官能团.