Development of High-Speed and High-Level Reduction Process of Difficult-to-Dewatering Sludge by Combined Reversible Flocculation and Multistage Ultrahigh-Pressure Expression System

采用升压超高压压榨与可逆絮凝相结合的方法，实现了难脱水污泥体积的快速减少。采用聚合氯化铝等多价阳离子无机电解质进行絮凝，对提高剩余活性污泥的脱水率极为有效，在15 MPa超高压作用下压榨，结合可逆絮凝，最终将压缩饼的含水率降至31wt%。该方法使活性污泥脱水时间缩短了51. 6%，污泥量减少99。百分之八十三通过一系列的试验，从脱水率和滤饼含水率两个方面都达到了研究目的。

High rate reduction in volume of difficult-to-dewatering sludge was achieved by step-up ultrahigh-pressure expression combined with reversible flocculation. Flocculation with inorganic electrolyte with multivalent cation such as poly aluminum chloride was extremely effective for the increase in the dewatering rate of excess activated sludge, and the water content of the compressed cake was finally reduced to 31wt% by expression under action of ultrahigh-pressure of 15 MPa combined with reversible flocculation. This new method shortened the total dewatering time of activated sludge by 51. 6% compared to the conventional method, and reduced the sludge volume by 99. 83%. The results derived from a series of experiments attained the research goals from the viewpoint of both the rate in dewatering and the water content of the compressed cake.