『保健医療科学』 2023 第72巻 第2号 p.179－180（2023年5月）
＜研修報告＞令和 4 年度研究課程
原水の水質変動に対応する高度浄水プロセスの水質改善効果や運転条件に関する研究
森田久男
A study on treatment performance and operation conditions of advanced drinking water treatment process to cope with fluctuations of raw water qualities
MORITA Hisao
Abstract
Pilot-scale experiments of ozone/biological activated carbon (BAC) process were conducted to reduce dis-infection by-products and their precursors, especially trihalomethane formation potential (THM-FP). There were no organic indicators (ultraviolet absorbance (E260), fluorescence intensity, and total organic carbon (TOC)) that were related to the behavior of THM-FP in all treatment processes. Two indicators, E260 and fluorescence intensity, of water after coagulation and sedimentation were used to predict THM-FP after ozo-nation. It was shown that precursors of dichloroacetic acid and trichloroacetic acid could be controlled using chloroform as an indicator. The ozone consumption per TOC to reduce THM-FP sufficiently was about 0.6 to 1.0 mg/mg C. Bromate formation after ozonation was controlled by feedback control of 0.1 mg/L of dissolved ozone at the inlet of biological activated carbon treatment.
keywords: ozonation, trihalomethane, organic indicator, ozone consumption, haloacetic acid