| abstract |
A treatment method for photoresist development wastewater that uses an RO device, wherein there is no need for neutralizing the RO permeate with an alkaline chemical, blockage of the RO membrane by slime is prevented or limited, and RO membrane permeate of good water quality can be obtained. After being brought into contact with a cation exchange resin without adjusting the pH, the photoresist development wastewater is clarified using an MF membrane device, etc. and then passed through a reverse osmosis membrane device to obtain the membrane permeate. |