Efficiency evaluation of alternative disinfectant for the removal of THMs precursors in drinking water supplies of India

Abstract

In pursuit of alternatives to disinfection by chlorine, there has been increased interest in the use of UV, O 3 , and H 2 O 2 in drinking water supplies to regulate the formation of Trihalomethane (THMs). Present study aimed the efficiency evaluation of these alternative disinfectants and combined effect of H 2 O 2 /UV for the removal of natural organic matter (NOM) which are major precursor of THMs. Water quality status of all the selected WTPs revealed that concentration range of NOM (1.70 to 3.8 mg/L) were fairly good but range value of THMs range (275.8 to 367.2 ppb) exceed BIS, USEPA, and WHO standard. The study was conducted in batch mode with real raw water collected from some of major drinking water treatment plants from eastern part of India. Experimental outcomes revealed that no significant removal of THMs precursors occurred during the individual treatment with UV, O 3 , and H 2 O 2 . However, the combination of H 2 O 2 /UV shown great efficiency in reduction of TOC (77%) and trihalomethane formation potential (THMFP) (46%) from raw water.