METHOD FOR TREATING A WASTE STREAM USING A BIOREACTOR AND A MEMBRANE FILTER

摘要

Method for treating a fluid aqueous waste stream comprising a biodegradable organic substance comprising feeding said stream into a bioreactor containing a fluid which contains biomass; reacting the biodegradable organic substance with the biomass in the bioreactor under essentially anaerobic conditions; taking a first flow from the bioreactor and using the first flow as a feed to a membrane filtration unit in which said feed is subjected to filtration thereby forming a permeate stream and a retentate stream; returning the retentate stream to the bioreactor; taking a second flow from the bioreactor as feed to a sludge treatment unit in which sludge treatment unit the second flow is separated into a third flow having an increased organic substance content compared to the second flow and a fourth flow having a decreased organic substance content compared to the second flow.