METHOD FOR MEMBRANE-TREATING FORMALDEHYDE-CONTAINING DISCHARGE WATER

摘要

Provided is a method for membrane-treating formaldehyde-containing discharge water enabling adequate membrane separation of formaldehyde without the use of ammonia. A method for membrane-treating formaldehyde-containing discharge water, the method comprising a step for adding a sulfite to the formaldehyde-containing discharge water and thereafter treating by reverse osmosis membrane separation. Preferably, the pH during the reverse osmosis separation membrane treatment is 7 or greater. Preferably, the sulfite is added so that [SO3]/[HCHO] (weight ratio) reaches 3-7.