Permeate Flux and Membrane Fouling Controlling of a Membrane Bioreactor with Gravity Flow to Treat Domestic Sewage and Landfill Leachate
重力出流式膜生物反应器的膜通量及膜污染控制研究

A novel membrane bioreactor(MBR) with gravity flow was applied to treat domestic sewage and landfill leachate.The variation of permeate flux and its impact factors were studied.The long-term test showed that the average permeate flux of this MBR could be 11.2L·(m2·h)-1 under the pressure of 8.5 kPa for treating domestic sewage while 6.4L·(m2·h)-1 and 15.0 kPa,respectively,for landfill leachate.The permeate flux increased with increase of aeration density and decrease of activated sludge concentration when aeration density was less than 400m3·(m2·h)-1.While activated sludge concentration and aeration density had hardly impact on the permeate flux when aeration density was more than 400m3·(m2·h)-1.The performances of several different cleaning solutions were tested and the results showed that NaOH-NaClO solution had the best cleaning efficiency.The permeate flux can recovered over 85% of the initial flux.A very high concentration of soluble extracellular polymeric substances(soluble EPS) existed in landfill leachate compared with domestic sewage,which was the main cause leading to a lower permeate flux when treating landfill leachate.