Abstract
Six Kinds of coke oven waste-waters produced in Japanese ironmaking works were analysed before and after the deammonia and active sludge treatment by means of UV, gel-and high performance liquid chromatography to characterize the organic substances and their changes in the treatment. The substances was found with chromatography to consist of five components, of which quantities varied with TOC, reflecting the coking conditions and coal pretreatment as well as the treatment. Among the components, the lightest two components were completely digested by the active sludge and the heaviest two were partly removed by the deammonia step where they may be precipitated on the coke filter probably through the oxidative condensation. The oxidative decomposition of the component appears to help its digestion in the successive active sludge treatment. In contrast, a significant part of the intermediate component stayed undigested. The waste water in the formed coking carried the largest amount of whole organic substances and the undigestiable intermediate component. The dry coalcharge tends to produce more organic substances and the intermediate component, although the sludge treatment suffered small influence. Detail correlation between the organic component distribution in the waste water and its coking variables can be obtainable by the present approach, providing a basis for the operation of active sludge adjustable to the variable quality of the waste water.
