Patent attributes
A process for treating biological oxygen demand (BOD), nitrogen and phosphorus containing wastewater, wherein the process includes providing wastewater influent to an oxygen-deficit aeration zone having activated sludge and mixing the wastewater influent with the activated sludge in the oxygen-deficit aeration zone to form a mixed liquor. The process further includes transferring the mixed liquor from the oxygen-deficit aeration zone to an oxygen-surplus aeration zone and transferring a portion of the mixed liquor from the oxygen-surplus aeration zone to a membrane filter wherein a filtrate is separated from sludge. In addition, the process includes recycling at least a portion of the sludge to the oxygen-deficit aeration zone as recycled activated sludge.
