Predicting Chlorine Residuals in Drinking Water: Second Order Model

Abstract

A major objective of drinking water treatment is to provide water that is both microbiologically and chemically safe for human consumption. Drinking water chlorination, therefore, poses a dilemma. Chemical disinfection reduces the risk of infectious disease, but the interaction between chemical disinfectants and precursor materials in source water may result in potentially harmful by-products. Chlorine consumption results in the formation of by-products, and the loss of chlorine residual reduces protection against potentially pathogenic bacteria. Therefore, much effort has been invested in characterizing the loss of chlorine residuals in raw and treated water. This paper presents a mathematical model based on the use of two second-order terms for predicting this loss or decay.