AWWA JAW59512

Utility managers will find this article useful because it discusses removal of dissolved organic carbon (DOC) by enhanced coagulation, which is considered a best available technology. The authors describe how to predict the proportion of dissolved organic compounds that will be removed during treatment with ferric- or aluminum-based coagulants. Often, it is necessary to remove a percentage of these compounds because they cause the loss of chlorine residual and the formation of disinfection byproducts in the distribution system. For the US and Australian waters modeled, the authors found that at a fixed pH alum removed more DOC than ferric coagulant did at lower doses. At higher doses, however, they observed that ferric coagulant removed more DOC than alum. Being able to predict the amount of DOC in treated water can be useful for such actions as designing a new treatment plant, optimizing the DOC removal of an existing plant, and influencing chlorine stability in a distribution system. Includes 20 references, table, figures.