Experimental Study on an Novel Environment-Friendly Coagulant for Treating Drinking Water

Abstract

An environment-friendly composite coagulant for treating drinking water was prepared by using [Al 2 (OH) n Cl 6-n ]m?[Fe2 (OH) NCl6-N ]M (PAFC), chitosan (CTS) and modified starch (MS). It is called PCS. Results indicated that the best proportion of this coagulant was V (0.1%wt PAFC): V (0.001%wt CTS): V (3%wt modified starch) = 25:6:8. If compared with using traditional coagulant such as PAC, adding the novel coagulant, turbidity and the mass concentration of Al3+ in the water were decreased by 5.17% and 51.1% respectively. Rapid and slow stirring speed in Jar test were evaluated and they were founded to be slight influence. And neutral pH and room temperature allow up to 97.2% turbidity removal. Low coagulant doses reached high turbidity removal percentage, so this coagulant has obvious economic and environmental benefits.