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Feng-San Water Treatment Plant (FSWTP) is the major public
water supplier for Greater Kaohsiung area. Its raw water mainly
come from surface water of Tung-Kang River and is supplemented
by ground water pumped from under the bed of Kao-Ping River. In
this research,the source waters came from both the raw water of
the FSWTP and the effluent from a pilot-scale pack-bed
biological nitrification column set up inside the FSWTP. Both
waters were sujected to batch ozone oxidation using ozone
demand flask. The effect of ozone dosage,bromide concentration,
pH value and cotact time on the concentrations of residual
ozone,bromate, and other organic surrogate parameters of the
ozonated water were studied. The results indicate that: compare
to raw water,nitrified water usually has higher residual ozone,
lower A254,and also higher bromate concentrations at same ozone
dosage,as reducing materials could be removed during the
biological nitrification process. High bromide,residual ozone,
pH value,and long contact time could facilitate the production
of bromate. When both raw water and the nitrified water were
subjected to ozonation and subsequent chlorination,the
trihalomethanes (THM),haloacetic acids (HAA), and their
formation potentials of the treated water of the latter were
lower than those of the former. And all the data indicated that
THM,HAA,and HAAFP reduced with increasing ozone dosages, except
THMFP which could increase at low ozone dosage,and subsequently
reduce at higher ozone dosage. Furthermore,higher bromide could
not only increase the total amount of halogenated organics,but
also the proportion occupied by the brominated species. And THM
and THMFP concentrations were found to be increased with
increasing pH value.
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