Zeta potential analysis of coagulation and biofiltration of water supply

Organic contaminants present in drinking water sources can change the water electrodynamic characteristics significantly. Such change may complicate the coagulation processes. Zeta potential analysis based on coagulation tests indicated that the trend of zeta potential changes in the coagulation of organic‐contaminated water sources is different from the classic coagulation process. In this case, the conformation of organic molecules may play an important role. The effect of biological treatment on the zeta potential was also investigated within a biofilter in the scale of 10,000 m3/day. The results showed that the biological process can change the zeta potential of turbidity particles, reducing the stability of the turbidity particles probably through biodegradation and bioflocculation, leading to the improvement of the coagulation process.