DBP FORMATION BEFORE AND AFTER IMPLEMENTATION OF MEMBRANE FILTRATION

摘要

The City of Kamloops (British Columbia) recently upgraded its drinking water treatment systemto include coagulation, flocculation, and membrane filtration (i.e., ultrafiltration) treatmentprocesses. The objective of the present study was to determine if implementation of themembrane treatment facility would reduce the formation of DBPs within the distribution system.Phase I of the study investigated trihalomethane (THM) and haloacetic acid (HAA) formation intwo sections of the distribution system – one section that received water treated by coagulation /flocculation / ultrafiltration / chlorination and one section that received the same source watertreated only by chlorination. Phase II of the study characterized THM and HAA formation usinga bench scale flow-through material-specific simulated distribution system (MS-SDS), madefrom pipe material resurrected from the City of Kamloops distribution system. The results of thepresent study showed that implementation of the membrane treatment facility did notsignificantly reduce THM or HAA formation in the distribution system. Further analysisrevealed that the THM and HAA precursors in the source water were relatively small andpredominantly hydrophilic. Small and hydrophilic DBP precursors typically cannot be removedby coagulation / flocculation / ultrafiltration treatment processes.