A pilot scale(10 m 3/d) anoxic/oxic membrane bioreactor(A/O MBR) was tested for dyeing wastewater treatment of woolen mill without wasting sludge in 125 days operation. Results showed that the effluent quality was exc...A pilot scale(10 m 3/d) anoxic/oxic membrane bioreactor(A/O MBR) was tested for dyeing wastewater treatment of woolen mill without wasting sludge in 125 days operation. Results showed that the effluent quality was excellent, i.e. effluent COD less than 25 mg/L, BOD 5 under 5 mg/L, turbidity lower than 0 65 NTU, and colour less than 30 DT, and met with the reuse water standard of China. The removal rates of COD, BOD 5, colour, and turbidity were 92 4%, 98 4%, 74% and 98 9%, respectively. Constant flux operation mode was carried out in this study, and backwash was effective for reducing membrane fouling and maintaining constant flux. Membrane fouling had heavy impact on energy consumption. More attention should be paid on pipe selection and design for the sidestream MBR system, too.展开更多
Particles and natural organic matter （NOM） are two major concerns in surface water, which greatly influence the membrane filtration process. The objective of this article is to investigate the efiect of particles, N...Particles and natural organic matter （NOM） are two major concerns in surface water, which greatly influence the membrane filtration process. The objective of this article is to investigate the efiect of particles, NOM and their interaction on the submerged ultrafiltration （UF） membrane flux under conditions of solo UF and coagulation and PAC adsorption as the pretreatment of UF. Particles, NOM and their mixture were spiked in tap water to simulate raw water. Exponential relationship, （JP/JP0 = a×exp{-k[t-（n-1）T]}）, was developed to quantify the normalized membrane flux dynamics during the filtration period and fitted the results well. In this equation, coefficient a was determined by the value of JP/JP0 at the beginning of a filtration cycle, refiecting the flux recovery after backwashing, that is, the irreversible fouling. The coefficient k refiected the trend of flux dynamics. Integrated total permeability （ΣJP） in one filtration period could be used as a quantified indicator for comparison of different hybrid membrane processes or under different scenarios. According to the results, there was an additive effect on membrane flux by NOM and particles during solo UF process. This additive fouling could be alleviated by coagulation pretreatment since particles helped the formation of flocs with coagulant, which further delayed the decrease of membrane flux and benefited flux recovery by backwashing. The addition of PAC also increased membrane flux by adsorbing NOM and improved flux recovery through backwashing.展开更多
文摘A pilot scale(10 m 3/d) anoxic/oxic membrane bioreactor(A/O MBR) was tested for dyeing wastewater treatment of woolen mill without wasting sludge in 125 days operation. Results showed that the effluent quality was excellent, i.e. effluent COD less than 25 mg/L, BOD 5 under 5 mg/L, turbidity lower than 0 65 NTU, and colour less than 30 DT, and met with the reuse water standard of China. The removal rates of COD, BOD 5, colour, and turbidity were 92 4%, 98 4%, 74% and 98 9%, respectively. Constant flux operation mode was carried out in this study, and backwash was effective for reducing membrane fouling and maintaining constant flux. Membrane fouling had heavy impact on energy consumption. More attention should be paid on pipe selection and design for the sidestream MBR system, too.
基金supported by the National Key Technology R&D Program in the 11th-Five Year Plan of China (No.2006BAD01B03)
文摘Particles and natural organic matter （NOM） are two major concerns in surface water, which greatly influence the membrane filtration process. The objective of this article is to investigate the efiect of particles, NOM and their interaction on the submerged ultrafiltration （UF） membrane flux under conditions of solo UF and coagulation and PAC adsorption as the pretreatment of UF. Particles, NOM and their mixture were spiked in tap water to simulate raw water. Exponential relationship, （JP/JP0 = a×exp{-k[t-（n-1）T]}）, was developed to quantify the normalized membrane flux dynamics during the filtration period and fitted the results well. In this equation, coefficient a was determined by the value of JP/JP0 at the beginning of a filtration cycle, refiecting the flux recovery after backwashing, that is, the irreversible fouling. The coefficient k refiected the trend of flux dynamics. Integrated total permeability （ΣJP） in one filtration period could be used as a quantified indicator for comparison of different hybrid membrane processes or under different scenarios. According to the results, there was an additive effect on membrane flux by NOM and particles during solo UF process. This additive fouling could be alleviated by coagulation pretreatment since particles helped the formation of flocs with coagulant, which further delayed the decrease of membrane flux and benefited flux recovery by backwashing. The addition of PAC also increased membrane flux by adsorbing NOM and improved flux recovery through backwashing.
