AWWA JAW55967

The objective of this study was to determine the rate of exertion of chlorine demand in new pipes. Calcium hypochlorite, sodium hypochlorite, and dissolved gaseous chlorine were contacted with full-size pipe sections (lined and unlined ductile iron, and polyvinyl chloride) under conditions that would be used in the disinfection of new mains. The subsequent demand and decay were measured. The process could be described by a biphasic kinetic model. The coefficients in the model could be correlated to the pipe type and diameter. From this work, a set of equations to estimate chlorine residual subsequent to main disinfection was developed.