Coagulation Features and Characteristics of Dissolved Organic Matter in Treatment of Combined Sewer Overflow Wastewater

摘要

in this study, coagulation features and molecular weight (MW) distribution dissolved organic matter (DOM) of CSO wastewater were investigated. FeCB and PAC were employed in the coagulation process, Both FeCB and PAC were effective for remove Turbidity and TP, the removal efficiency were all above 90% when the dosages .was reasonable; optimal removal efficiency of COD were appropriate of 60-70%; but the removal efficiency of NH4+-N and TN were 10-20% only. The comparison results of removal efficiency of COD, Turbidity, NH4+-N, TN and TP in different concentration of raw wastewater with the same dosages of FeC13 and PAC were also investigated. The results showed that water quality of raw wastewater was one of the influential parameters for the optimized treatment of the wastewater. The MW distribution of DOM of the raw wastewater and coagulated samples was analysis by gel filtration cbromatography (GFC) and ultrafiltration technology. Compared with the initial wastewater, coagulated samples had much narrower distributions of MW. DOM fraction MW>30kDa can be removed by both FeCI3 and PAC.