Abstract
Using the secondary effluents from 4 domestic wastewater treatment plants and their advanced effluents by flocculation-sedimentation, activated carbon adsorption and ozonation processes, reduction effect of their trihalomethane and total organic halide formation potentials (THMFP and TOXFP), and removal effect of each component in TOXFP samples by GC-MS analysis were examined, respectively.
It was shown that effective removal of NH4-N concentration in the secondary effluent was very important in order to reduce its THMFP and TOXFP, since both potentials were very susceptible to NH4-N component. The averaged 32-34% of THMFP and 25-24% of TOXFP in the secondary effluents were reduced by flocculation-sedimentation and ozonation processes, respectively. In case of the combination process of activated carbon adsorption after flocculation-sedimentation, high removal effciencies of COD and TOC were obtained and reduction efficiencies of THMFP and TOXFP were 76% and 71% on the average, respectively. Main components of halogenated organic compounds in the secondary effluents were trichloroacetic acid. dichloroacetic acid and chloral hydrate, and their components could be reduced effectively by the same combination process.
