Experimental Study On South-to-North Water Diversion Raw Water By Combined Potassium Permanganate-Powder Activated Carbon

In the high temperature season,the problem of algae pollution of the middle route of the South-to-North Water Transfer Project puts a lot of pressure on the operation of water plants along the route.Appropriate algae removal technology is an effective way to solve the problem of algae pollution.In this study,the water source of the Handan section of the South-to-North Water Diversion Project was used as the raw water.The water purification effect of potassium permanganate pre-oxidation,powder activated carbon（PAC）,and the combined process in reducing the dosage of coagulant was investigated.The research has significantly improved the removal effect of algae and pollutants in raw water.The conclusions of this study are as follows:（1）Through the beaker test,the removal effect of polyaluminum chloride on conventional pollutants was analyzed.The results showed that when polyaluminium chloride was added at 10 mg/L,the average removal of chl-a,turbidity,COD_Mn,and UV₂₅₄ was removed.The rates were 76.60%,79.81%,13.43%,and 27.5%.COD_Mn and UV₂₅₄ can not be effectively removed by conventional methods.（2）Experimental studies on the treatment of source water from the South-to-North Water Diversion Project with a combined process of potassium permanganate pre-oxidation,activated carbon pre-adsorption and conventional treatment,the results showed that the removal rate of chl-a,turbidity,COD_Mn,and UV₂₅₄ by the combined process of 0.4 mg/L potassium permanganate and conventional coagulation was 86.69%,89.14%,29.63%and 37.5%;10 mg/L powder activated carbon and conventional coagulation combined process for chl-a,turbidity,COD_Mn,and UV₂₅₄ The removal rates were 86.19%,76.76%,30.56%and 42.5%.（3）Using potassium permanganate and activated carbon adsorption to study pollutants in water,response surface methodology to optimize the combination of potassium permanganate and powdered activated carbon combined with conventional processes to achieve the best algae removal effect of 93.58%.The average removal rates of chl-a,turbidity,COD_Mn,and UV₂₅₄ in raw water of potassium acid activated carbon reached 91.15%,92%,42.59%and 56.06%.（4）Based on the beaker experiment,the dynamic test is simulated by simulating the process and process parameters of the water plant.The results show that the combined process of 0.4 mg/L potassium permanganate and 8 mg/L powdered activated carbon has the best effect on dynamic algae removal.After filtration,the chl-a,turbidity,COD_Mn,and UV₂₅₄ removal rates were maintained at 95.1%,98%,34.2%,and 61.3%,and the aluminum content was lower than 0.2 mg/L in the Drinking Water Safety and Health Standard（GB5749-2006）.