Effects of polydiallyldimethyl ammonium chloride coagulant on formation ofchlorinated by products in drinking water

The objectives of this research work was to evaluate the reduction of THM p recursors by cationic p-DADMAC and determine the correlations between the c hlorine demand and trihalomethane formation in the presence of electrolyte solutions and ambient light. The chlorine demand was found to be significan tly reduced provided that the H2SO4 electrolyte was fed to the sample solut ions. The amount of CHCl3 formation was also decreased when the Na2SO4 elec trolyte was introduced in spite of the levels of light intensity. The p-DAD MAC can not only effectively remove the turbidity but also reduce the forma tion of CHCl3. The optimum dosage of p-DADMAC for reducing the turbidity, T OC and CHCl3 in the humic acid and source water samples was determined and depended upon the nature of organics. (C) 1999 Elsevier Science Ltd. All ri ghts reserved.