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
For effective wastewater reclamation and water recovery,the treatment of natural and effluent organic matters(NOM and EfOM),toxic anions,and micropollutants was considered in this work.Two different NOM(humic acid of ...For effective wastewater reclamation and water recovery,the treatment of natural and effluent organic matters(NOM and EfOM),toxic anions,and micropollutants was considered in this work.Two different NOM(humic acid of the Suwannee River,and NOM of US and Youngsan River,Korea),and one EfOM from the Damyang wastewater treatment plant,Korea,were selected for investigating the removal efficiencies of tight nanofiltration(NF)and ultrafiltration(UF)membranes with different properties.Nitrate,bromate,and perchlorate were selected as target toxic anions due to their well known high toxicities.Tri-(2-chloroethyl)-phosphate(TCEP),oxybenzone,and caffeine,due to their different K_(ow) and pK_(a) values,were selected as target micropollutants.As expected,the NF membranes provided high removal efficiencies in terms of all the tested contaminants,and the UF membrane provided fairly high removal efficiencies for anions(except for nitrate)and the relatively hydrophobic micropollutant,oxybenzon.Through the wetlands,nitrate was successfully removed.Therefore,a fair process of combining membranes with an engineered wetland could be proposed for sustainable wastewater reclamation and optimum control of contaminats.展开更多
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.
基金This research was supported by the National Research Laboratory Program by the Korea Science and Engineering Foundation(Grant No.R0A-2007-000-20055-0)partially supported by the Basic Research Project through a grant provided by the GIST in 2008.
文摘For effective wastewater reclamation and water recovery,the treatment of natural and effluent organic matters(NOM and EfOM),toxic anions,and micropollutants was considered in this work.Two different NOM(humic acid of the Suwannee River,and NOM of US and Youngsan River,Korea),and one EfOM from the Damyang wastewater treatment plant,Korea,were selected for investigating the removal efficiencies of tight nanofiltration(NF)and ultrafiltration(UF)membranes with different properties.Nitrate,bromate,and perchlorate were selected as target toxic anions due to their well known high toxicities.Tri-(2-chloroethyl)-phosphate(TCEP),oxybenzone,and caffeine,due to their different K_(ow) and pK_(a) values,were selected as target micropollutants.As expected,the NF membranes provided high removal efficiencies in terms of all the tested contaminants,and the UF membrane provided fairly high removal efficiencies for anions(except for nitrate)and the relatively hydrophobic micropollutant,oxybenzon.Through the wetlands,nitrate was successfully removed.Therefore,a fair process of combining membranes with an engineered wetland could be proposed for sustainable wastewater reclamation and optimum control of contaminats.
