ULTRAHIGH-LEVEL METHOD FOR TREATING WATER AND WATER TREATMENT SYSTEM TO BE USED THEREIN

PROBLEM TO BE SOLVED: To provide a method and a system for treating water, in each of which a hardly biodegradable substance, COD, BOD and fungi can be decreased remarkably, stable treated water, wherein the quality is hardly fluctuated even when the quality of the water to be treated is fluctuated, and is kept within a constant good range, can be obtained, the water to be treated can be treated regardless of the water quality by using a small amount of ozone and hydrogen peroxide and the operation of treating water can be conducted efficiently at a low running cost. SOLUTION: The ultrahigh-level method for treating water is characterized in that the water to be treated is subjected at the least to such advanced oxidation treatment that the water to be treated is oxidized while supplying ozone and hydrogen peroxide and such biological treatment that organic matter is decomposed by a microbe, the biological treatment is performed after the advanced oxidation treatment and the concentration of ozone dissolved in the water to be treated is controlled within a constant range in the advanced oxidation treatment. COPYRIGHT: (C)2007,JPO&INPIT