Spectrum Comparison of Raw Water Using Three-Dimensional Fluorescence Excitation-Emission Matrix and Control of Disinfection By-Product by the Color of the Filtered Water

Abstract

There is a risk of Disinfection By-Product (formation exceeding water quality standards due to water pollution caused by rainfall at water treatment plants located in the mountainous areas in Tokyo. Therefore, we studied Humin which creates DBP, in order to control DBP formation. We used Three-Dimensional Fluorescence Excitation-Emission Matrix to study Humin and examined the performance of flocculants for removing Humin. As a result, it became clear that the Humin created in all of the mountainous areas of Tokyo share similar fluorescence properties. It revealed that correlations between the fluorescence intensity, the color and the DBP Formation Potentials (DBP FP) were strong. So we were able to make a formula to calculate DBP FP from the fluorescence intensity or from the color. Thereby, we could control DBP formation by monitoring the color of filtered water. Furthermore, it was thought that here are two factors which have an effect on removing humic acid, one of which is the flocculation of aluminum and the other is the pH decrease. We applied these results to the operating conditions of the water purification plants, and we use the results to control DBP formation.