TREATMENT OF WASTE WATER

PROBLEM TO BE SOLVED: To provide a method for efficiently treating a waste water to be treated contg. low concn. of org. compd. with a high b.p. such as (CH3 )4 NOH (TMAH) as a main solute ingredient and an inorg washing waste water contg. low concn. of ammonia. SOLUTION: This method for treating waste water comprises an ammonia recovering process wherein a waste water to be treated contg. low concn. or org. compd. with a higher b.p. than that of water as a main solute ingredient and an inorg. washing waste water contg. low concn. of ammonia are mixed and this mixed waste water is distilled to recover ammonia and a concentrating process wherein the mixed waste water from which ammonia is recovered is concentrated to obtain a conc. waste water. It is possible thereby to reduce remarkably the amt. of waste water by treating two kinds of waste water with different properties and to safely and easily recover ammonia. In addition, the recovered ammonia and the conc. waste water can be decomposed into mainly nitrogen, carbon dioxide and water by supercritical water reaction.