微絮凝-直接过滤工艺在城市污水深度处理中的应用研究

The study of phosphorus removal for secondary effluent in advanced municipal wastewater treatment using microflocculation-direct filtration

微絮凝 -直接过滤工艺是一种将混凝反应、沉淀截留集中在同一滤柱内同步完成的高效水处理工艺。该工艺应用于城市污水的深度处理中 ,通过絮凝剂的加入 ,具有同步去除PO3 -4 P、SS和部分COD的功能。本文研究了该工艺对二级处理出水中PO3 -4 P、SS和COD的去除效果及其规律。研究表明 :采用聚合氯化铁 (PFC)作为絮凝剂 ,当Fe/P摩尔比为 2∶1时 ,水中PO3 -4 P的去除率达 98.8% ,浓度可降至 0 .1mg/L以下 ,同时SS、COD去除率也有明显提高。与传统的混凝、沉淀除磷工艺相比 ,该工艺具有操作简单、结构紧凑、占地面积小、污泥量少等优点 ,是一种更为经济和简单的处理单元 。

Microflocculation direct filtration is a high efficient process which combines the flocculation and sediment in one filter unit. In this paper, advanced municipal wastewater treatment process, especially process of removing phosphorus ,SS,COD from secondary effluent of sewage treatment system by microflocculation direct filtration were studied .When PFC was applied as coagulating agent with the dosage 2.0mol Fe 3+ /molPO 3- 4 P, the PO 3- 4 P removal rate reached 98.8% and an effluent concentration of 0.1mg/L PO 3- 4 P could easily be obtained. SS and COD removal efficiencies also increased. Comparing to conventional processes with flocculation and sedimentation, this process is more economically and technically applicable for the post treatment units due to compact construction, easy operation and reduction for space.