Patent ID: 9206059
Filing Date: 2015-12-08
Classification: B01D,C02F,Y02W

Abstract:
1. A method of treating a waste stream with a reverse osmosis or nanofiltration membrane unit and removing biodegradable compounds from the waste stream at a point upstream of the reverse osmosis or nanofiltration membrane unit to prevent biofouling of the reverse osmosis or nanofiltration membrane unit, the method comprising: upstream of the reverse osmosis or nanofiltration membrane unit, directing the waste stream into a bioreactor filled with packing elements, that support a biofilm, having a void fraction of at least 70% and wherein the packing elements within the bioreactor have a specific surface area of at least 750 m biologically treating the waste stream by directing the waste stream through the bioreactor; limiting the removal efficiency of suspended solids to 30% or less in the bioreactor by maintaining the velocity of the waste stream passing the packing elements to a velocity of at least 20 m/h; wherein the method of treating the waste stream is accomplished in the absence of any biocide or biostatic compound; and after directing the waste stream through the bioreactor, directing the waste stream to the reverse osmosis or nanofiltration membrane unit and wherein the reverse osmosis or nanofiltration membrane unit removes dissolved solids from the waste stream.