剩余污泥回流至初沉池对A/O污水处理系统的影响

Influence of Excess Sludge Return to Primary Sedimentation Tank on A/O Sewage Treatment System

基于静态模拟试验结果,进行了将A/O处理工艺中二沉池剩余污泥按比例回流至初沉池的生产性试验,运行结果显示,这一措施能明显提高初沉池的沉淀效率,且当剩余污泥的回流比例为40%～60%时,初沉池对SS、COD等去除效果最佳,同时可提高A/O池进水的可生化性及处理能力,并降低浓缩池出泥含水率。该工艺运行稳定,可有效降低污水处理厂的总体运行成本。

Based on the static simulation experiment, a full-scale test was conducted by returning in proportion excess activated sludge from secondary sedimentation tank to primary sedimentation tank in A/O process. The result shows that the efficiency of primary sedimentation tank can be obviously increased, and when the returned sludge ratio is between 40% and 60%, the removal effect of pollutants is the best. At the same time, the biodegradability of the influent and treatment capacity of the secondary treatment can be improved, and the water content of sludge from sludge thickener can be reduced. The process operates steadily and can effectively decrease the total operation cost of sewage treatment plant.