Metabolic uncoupler,3,3’,4’,5-tetrachlorosalicylanilide addition for sludge reduction and fouling control in a gravity-driven membrane bioreactor  

作　　者：An Ding Yingxue Zhao Huu Hao Ngo Langming Bai Guibai Li Heng Liang Nanqi Ren Jun Nan 

机构地区：[1]State Key Laboratory of Urban Water Resource and Environment(SKLUWRE),School of Environment,Harbin Institute of Technology,73 Huanghe Road,Nangang District,Harbin 150090,China [2]Faculty of Engineering,University of Technology Sydney,Sydney,NSW 2007,Australia

出　　处：《Frontiers of Environmental Science & Engineering》2020年第6期53-64,共12页环境科学与工程前沿（英文）

基　　金：This work was jointly supported by the National Natural Science Foundation of China(Grant No.51608150);the Open Project of State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(No.ES201810-02);the Natural Science Foundation of Heilongjiang Province(No.E2017042);the Natural Science Foundation of Harbin(No.2017RAQXJ206);special support from the China Postdoctoral Fund(No.2018T110303);special support from the Heilongjiang Postdoctoral Found(No.LBH-TZ14).

摘　　要：The gravity-driven membrane bioreactor(MBR)system is promising for decentralized sewage treatment because of its low energy consumption and maintenance requirements.However,the growing sludge not only increases membrane fouling,but also augments operational complexities(sludge discharge).We added the metabolic uncoupler 3,3’,4f,5-tetrachlorosalicylanilide(TC$)to the system to deal with the mentioned issues.Based on the results,TCS addition effectively decreased sludge ATP and sludge yield(reduced by 50%).Extracellular polymeric substances(EPS;proteins and polysaccharides)decreased with the addition of TCS and were transformed into dissolved soluble microbial products(SMPs)in the bulk solution,leading to the break of sludge floes into small fragments.Permeability was increased by more than two times,reaching 60-70 L/m2/h bar when 10-30 mg/L TCS were added,because of the reduced suspended sludge and the formation of a thin cake layer with low EPS levels.Resistance analyses confirmed that appropriate dosages of TCS primarily decreased the cake layer and hydraulically reversible resistances.Permeability decreased at high dosage(50 mg/L)due to the release of excess sludge fragments and SMP into the supernatant,with a thin but more compact fouling layer with low bioactivity developing on the membrane surface,causing higher cake layer and pore blocking resistances.Our study provides a fundamental understanding of how a metabolic uncoupler affects the sludge and bio-fouling layers at different dosages,with practical relevance for in situ sludge reduction and membrane fouling alleviation in MBR systems.

关 键 词：Gravity-driven membrane(GDM) Energy uncoupling Permeability Sludge reduction Membrane fouling Fouling layer 

分 类 号：X703[环境科学与工程—环境工程]