LONG TERM ON-SITE EXPERIMENTS ON PURIFICATION FOR STRONG POLLUTED RIVER BY BIO-ACTIVE CONTACT OXIDATION METHOD

The large-scale experimental channels were constructed in 1994 in the course of the Takaya-gawa river which is a branch of the Ashida river, in Fukuyama-city. In these experimental channels, two kinds contact oxidation materials such as coral stone and deoiled coal paved into one channel and another channel which called a control channel were paved by nothing. The conduction period of water to these channels is about 80-55 days for each season during Aug. 1999 to Nov. 2000.The purification effects for the strong polluted river-water were estimated by several items of water quality and sludge. In this paper, items of BOD, nitrogen and phosphorus were especially considered from the angles such as particle component and dissolved component.