表面活性剂改进活性污泥的脱水性能及其作用机理

表面活性剂无论单独或与 FeCl₃和 CaO混合使用 ,都能提高离心脱水效果 ;表面活性剂与 FeCl₃和 CaO混合作用 ,污泥经过滤脱水后的含水率比不加表面活性剂的明显降低 .对于离心脱水 ,当表面活性剂的加入量与污泥干重比为 0.109时 ,脱水污泥的体积比不加表面活性剂的降低 11%左右 ;对于过滤脱水 ,当用表面活性剂 (加入量为污泥干重的 0.08)与 FeCl₃和 CaO同时调理时 ,污泥的含水率 (78.92%)比只用 FeCl₃和 CaO调理的降低约 6%.进一步的研究显示 ,表面活性剂之所以能降低脱水污泥的含水率是与其能加快污泥的沉降速度及促进污泥表面的蛋白质和 DNA释放、减少污泥颗粒间的间隙水有关 .

Surfactant Improving Activated Sludge Dewaterability and Its Mechanism

Effects of surfactant used separately or together with ferric chloride and lime water on activated sludge dewaterability and its mechanism were investigated in this paper Results showed that the centrifugal dewatering efficiency could be increased no matter surfactant used solely or plus ferric chloride and calcium oxide.It was observed that when surfactant,ferric chloride and calcium oxide were applied to condition sludge,and vacuum filtrtion was employed to dewater,the water content of dewatered sludge was decreased significantly compared with only ferric chloride and calcium oxide used.To a centrifugal dewatering,the sludge volume,compared with absence of surfactant,was reduced by almost 11% in the case of a 0 109 ratio of surfactant to dry sludge weight.when sludge was preconditioned with surfactant,ferric chloride and lime ahead of filtration,a water content of 78 92% was obtained as the ratio of surfactant to dry sludge was 0 08,which was declined by about 6% compared with just ferric cholride and calcium oxide utilized.Further studies indicated that the mechanisms of surfactant increasing sludge dewaterability were it could improve the sedimentation rate,promote the release of protein and DNA from sludge surface and reduce the amound of interstitial water bounded in the sludge.