Evaluation of Ozonation By-Products from Two California Surface Waters

摘要

Ozonation by-products were analyzed for two surface water sources in Southern California--Los Angeles Aqueduct Water (LAAW) and State Project Water (SPW). Included are data obtained when LAAW was being treated at the Los Angeles Aqueduct Filtration Plant and similar data obtained during a two-day experiment in which the plant was treating SPW. Some batch-scale ozonation studies are also reported. Ozonation by-products were monitored using three methods: closed-loop stripping analysis, nonionic resin accumulation, and a direct aqueous derivatization method for low-molecular-weight aldehydes, each followed by gas chromatography-mass spectrometry analysis of the extracts. The major neutral by-products appear to be aliphatic aldehydes, but the levels are unexpectedly low in SPW compared with LAAW treated under similar conditions. Low levels of several other compounds were found in ozonated water, including bromoform and some compounds tentatively identified as ketones.