INTEGRATION OF WET OXIDATION AND NANOFILTRATION FOR TREATMENT OF RECALCITRANT ORGANICS IN WASTE-WATER

Wet oxidation and nanofiltration are employed in an integrated system for the treatment of bioresistant industrial wastewaters. The partial oxidation products formed during a brief period of pretreatment in a l ow pressure WO reactor are separated by nanofiltration, and larger mol ecules are recycled into the reactor where they undergo further oxidat ion. Experiments were carried out with polyethylene glycol as a model compound in aqueous solution, representing polymer manufacture wastewa ter, The results demonstrate that by using a combination of an oxidati ve and a separative step, a higher selectivity of the overall process toward partial oxidation can be achieved. The permeate leaving the fil tration step is mainly composed of short chain organic acids which cou ld be readily biodegraded in a subsequent biological treatment, or dis charged if concentrations are low.