Treatment of Micro-polluted Raw Water by Activated Carbon/Sand Filter

The previous common sand filter was reconstructed into activated carbon/sand filter in Jiaxing Nanmen Waterworks.Under the steady operating condition,the activated carbon/sand filter reduces NH3-N of 0.70 to 1.30 mg/L,and has higher the removal efficiencies of CODMn and Mn than the previous common sand filter,with 15% to 22% and 90% to 100% respectively,but water treatment cost is increased only by 0.025 yuan/m3.The practice shows that the combined process of enhanced coagulation and biological activated carbon/sand filter is an economic choice for treating raw water polluted by NH3-N of less than 1.5 mg/L,CODMn of 4 to 6 mg/L,and Mn of less than 0.7 mg/L.