An improved chloroform surrogate for chlorine dioxide- and alum-treated waters

作者：Granderson Corey W; Pifer Ashley D; Fairey Julian L^*

来源：Journal American Water Works Association, 2013, 105(3): 45-46.

DOI：10.5942/jawwa.2013.105.0016

Reliable disinfection by-product (DBP) surrogates could be used to optimize dosing of chemicals for DBP precursor removal. In this study, ultraviolet- (UV-) and fluorescence-based DBP surrogates were evaluated for two drinking water reservoirs. Free chlorine DBP formation potential (FP) tests were performed on (1) raw waters, (2) alum-coagulated (AC) waters, and (3) chlorine dioxide (ClO2)-treated and alum-coagulated (CD-AC) waters. On average for the two reservoirs, AC decreased chloroform (TCM) FP by 30 and 42%, whereas CD-AC decreased TCMFP by 61 and 67%. Fluorescence excitation-emission matrixes from unchlorinated raw and treated samples were decomposed into component fluorophore groups using parallel factor (PARAFAC) analysis. Maximum intensity (FM) values of four humiclike fluorophore groups were more strongly correlated with TCMFP (R-2 %26gt; 0.92) than were UV-based surrogates (R-2 = 0.67-0.84). These results indicate fluorescence-PARAFAC could be used to track DBP precursor removal and optimize ClO2 and alum doses to curb DBP formation.

• 出版日期2013-3