[Determination for optimal ozone dose in O3-BAC].

The ozonation can increase biodegradability of water and the biofilter after ozonation can increase biostability of water. The result shows that with different doses of ozone between 2 and 8 mg/L, ozonation can increase AOC-P17, AOC-NOX and BDOC by 20.9%-85.5%, 42.1%-158.2% and 21.4%-84.4%, respectively. The optimum ozone dose for maximum AOC and BDOC formation is 3 mg/L. In the test, the AOC of effluent from BAC is lower than 50 microg/L (acetate-C). The AOC concentration is between 35.9 and 46.6 microg/L (acetate-C), and the effluent belongs to biostability.