Comparison of Fe–Mn enhanced coagulation and O3-BAC for removing natural organic matter from source waters: a case study

AbstractThis plant-scale investigation compared two process improvement strategies for Lianyungang drinking water treatment plant (L-DWTP), a typical plant employing conventional processes to treat source water impacted by seasonal non-point pollution. Hierarchical cluster analysis grouped it into two clusters, i.e. normal period and polluted period. Originally, the L-DWTP exhibited poor organic matter removal efficiency, and 76.7% of the effluent permanganate index (CODMn) levels exceeded the state regulation requirement (<3 mg/L). In addition, chloroform concentration was observed to exceed the regulation requirement (60 μg/L) by 14.2 and 56.2% in normal and polluted periods. The combined use of FeCl3 and KMnO4 (Fe–Mn enhanced coagulation) increased the CODMn removal efficiency by 10.6%, and decreased the chloroform formation by 26.4%. It indicates that about 94.5% of effluent CODMn values and nearly all of chloroform levels may meet the standard in normal period. However, Fe–Mn enhanced coagulation sho...