| In this dissertation, the follows were studied: 1) The methods for the measurements of the concentrations of biodegradable organic matter (AOC and BDOC) and haloacetic acids (HAAs); 2) The removal characteristics of AOC, BDOC, DBPs and DPB precursors in water treatment processes; 3) The variation characteristics of AOC, BDOC, THMs and HAAs in distribution systems, 4) The relationship among disinfection, disinfectin by-products and biological stability in drinking water; and 5) the selection of the optimal disinfection processes. Based on the research, the following conclusions were drawn:1. For the measurement of AOC, the method of inoculating P17 and NOX strains step by step, which was presented by this dissertation, is better than the other two methods (separately inoculating and simultaneously inoculating methods) that were recommended widely in peer-reviewed papers.2. In the course of BDOC measurements, the BDOC degradation could be depicted by first-order kinetics model as BDOCt=BDOCu(1-10-0.077t). Based on the kinetics equation and real retention time of water in distribution systems, the BDOC3 that took three days in measurement was proposed to substitute the BDOC28 that took 28 days. The modification of BDOC measurements makes this method easily applicable.3. The method for the measurement of HAAs was established and further polished. The modification was made to use methanol to supersede carcinogenic and easily explosive diazomethane that was widely used by other researchers as the esterification reagent so that the measurement procedure was much more safe and applicable.4. It was observed that pre-chlorination had great impacts on concentrations of AOC and DBPs in source water. Pre-chlorination resulted in that AOC concentrations increased by 223%~498%, and HAA and THM concentrations elevated to 19μg/L and 30μg/L from nothing, respectively.5. AOC and HAAs were removed by 40%~60% with mostly above 50% by...
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