2007-01-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/705437摘要：在傳統淨水程序中，消毒劑與水中有機物質反應將產生具致癌潛勢的消毒副產物，其中三鹵甲烷與鹵乙酸為最主要的兩種指標物質，在歐美各國已受到法令管制。目前美國環境保護署規定總三鹵甲烷及五種鹵乙酸濃度標準各為80及60 μg/L，而台灣現行的飲用水水質標準只規定三鹵甲烷濃度須在80 μg/L以下，尚未規範鹵乙酸濃度。由於台灣大多數的自來水水廠為實行前加氯消毒程序，不但可能形成大量消毒副產物，當原水有機物質含量高時，情形將更為嚴重。一些研究結果顯示，鹵乙酸在餘氯含量低的配水管線或儲水槽中可能會進行生物降解作用，但其生物降解的反應機制與不同淨水程序造成鹵乙酸濃度變化的原因，目前仍尚未釐清。本研究嘗試建立台灣自來水處理程序水中鹵乙酸的濃度及分布資料，並藉由分析其中數個鹵乙酸含量高的水廠水樣，分別探討不同處理程序（包含混凝、沉澱、過濾等程序）中鹵乙酸生成與降解的可能機制。另外，由於在過濾程序中可能有生物膜附著於濾材中，鹵乙酸進行生物降解的可能性極高，因此本研究將針對鹵乙酸生物降解作用進行更深入的探討。此研究不但能提供飲水處理相關單位及研究人員更詳細的鹵乙酸在水處理程序中分布資料，並藉由進一步深入探討鹵乙酸的生成與降解機制，期能有助於實場運作的處理技術與效率，進而提昇水質。<br> Abstract: Disinfection byproducts (DBPs) come from the reaction of disinfectant and natural organic matter. Trihalomethane and haloacetic acid are two of the major DBPs from chlorination and are currently regulated in many countries. The Stage II Disinfection/Disinfectant Byproducts Rule (D/DBPR) of United State Environmental Protection Agency (USEPA) requires the concentrations of total trihalomethanes (THM4) and five HAAs (HAA5) to be under 80 and 60 &micro;g/L (running annual average), respectively. Currently, only THM4 are regulated under the water quality standards of the ROC Environmental Protection Agency (hence after EPA) as 80 &micro;g/L. Since most water utilities in Taiwan use prechlorination, DBPs can be form in large quantity in the beginning of the treatment, especially in plants processing high organic raw water. Several studies indicated that HAA can be biodegraded in the distribution or storage where chlorine residual is low. However, the HAA concentration reduction within the treatment process was unclear. And, the mechanisms of HAA reduction by treatment process were unclear. The objective of this study is to investigate the detailed HAA formation, physical-chemical reduction, and biodegradation in each process including coagulation/flocculation, sedimentation, and filtration. Water samples from three to five utilities with high HAA concentrations will be collected and tested for their HAA concentration and biodegradation potential. With special focus on the filtration process - where major biodegradation may possibly take place, the HAA concentration may be greatly reduced. The results from this study will help water utilities and regulating agencies to better understand and control HAA in drinking water.鹵乙酸消毒副產物生物膜生物降解haloacetic aciddisinfection by-productbiofilmbiodegradation