Patent ID: 6592763
Filing Date: 2003-07-15
Classification: C02F,Y02W,Y10S

Abstract:
A method for purifying, in an essentially closed circuit water purification system, an aqueous flow from a processing unit, comprising the steps of:(a) supplying to a bioreactor, and combining therein, the aquecus flow, as well as a discharge flow from a membrane filtration unit, the membrane filtration unit being located downstream of the bioreactor and included in the closed circuit water purification system; (b) allowing microbiological conversion of biodegradable constituents present in and contaminating the combined aqueous and discharge flows, to take place in the bioreactor, thereby, generating an effluent flow from the aqueous and discharge flows thus treated, the effluent flow exiting from the bioreactor; (c) supplying the effluent flow from the bioreactor to an ultrafiltration unit so as to separate therein the effluent flow into a permeate flow and a concentrate flow; (d) supplying at least a portion of the permeate flow to a membrane filtration unit so as to separate therein the permeate flow into a product flow and the discharge flow, the discharge flow comprising dissolved substances; and (e) supplying the discharge flow to the bioreactor, as noted in step (a), supplying at least a portion of the product flow from the membrane filtration unit to the processing unit, and supplying at least a portion of the concentrate flow from the ultrafiltration unit to the bioreactor.