AWWA WQTC58824

In Germany, new regulations for swimming pool water treatment generally require the use of activated carbon. Activated carbons with enhanced catalytic activity are of special interest, because manufacturers promise a better performance in pool water treatment concerning the removal of combined chlorine and disinfection byproducts. Yet they are mainly applied as powdered activated carbons. Process combinations for pool water treatment, permitted according to the German regulations, also include the application of granular activated carbon (GAC). The long time behavior of GAC with enhanced catalytic activity is yet not known. It is of special concern that, due to the enhanced production of biodegradable substances by catalytic conversion of NOM, microorganisms may proliferate in the GAC beds. Three different types of GAC (one standard GAC, two catalytic GACs) are compared for their long time behavior in pool water treatment. In a pilot plant operated with real swimming pool water, production and removal of disinfection byproducts (THM, HAA, AOX), of biodegradable substances (AOC), of bacteria (P. aerugionas, Legionella, Coliforms, HPC) as well as the removal of chlorine and chloramines are monitored as functions of GAC bed depth. Includes 8 references, table, figures.