TREATMENT OF PHOTORESIST-CONTAINING WASTE WATER

摘要

PURPOSE:To efficiently treat a photoresist-contg. waste liquid and to effectively remove COD therefrom by subjecting the waste water to a UV irradiation treatment under an alkaline condition and under addition of an oxidizing agent, then passing the liquid through a reverse osmosis membrane device, thereby treating the liquid. CONSTITUTION:A pH adjusting agent injecting pipe 1'' is disposed to a waste water tank 1 and the waste photoresist water in the tank 1 is kept at about 8-13 pH by a pH adjusting agent such as caustic soda injected from the injecting pipe 1''. The waste water subjected to the pH adjustment is pumped 7 into a UV ray oxidizing device 2 and a proper amt. of the oxidizing agent is added from an oxidizing agent injecting pipe 2' to the water just before the supply of the waste water to said device. The waste water which is kept at about 8-13 pH and is added with the oxidizing agent is subjected to UV irradiation, by which the photoresist contained therein is decomposed or modified to the hardly insolubilizing state.