Xu G R, Yan Z C, Wang Y C, Wang N
State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, P.O. Box 2602, 202 Haihe Road, Nangang District, Harbin, Heilongjiang Province, Postal code 150090, China.
J Hazard Mater. 2009 Jan 30;161(2-3):663-9. doi: 10.1016/j.jhazmat.2008.04.008. Epub 2008 Apr 10.
An investigation was made to study the feasibility of recovering the Alum from coagulation sludges and reusing it in chemically enhanced primary treatment (CEPT) process to make the CEPT more cost-effective and recover the resource (Alum) efficiently. The optimum condition and efficiency of the acidification method for Alum recovery from coagulation sludge were investigated in the test. The results show that when the recovery rate of Alum reaches its highest level, 84.5%, the reduction rate of sludge is 35.5%. It turns out that the capability of recovered coagulant to remove turbidity, UV(254) and COD are 96%, 46% and 53%, respectively. The results prove that the recovered coagulants could be used in CEPT and the efficiency of recovered coagulant to remove pollutants is similar to that of fresh coagulant. Although some substances will be enriched during recycle, they have little effect on the quality of treated wastewater. The experiments verify that it would be an advisable and cost-effective way to recover Alum from coagulation sludges in water treatment and chemical wastewater treatment, and it could be then recycled to CEPT as well as reduce sludge volume.
开展了一项调查，以研究从混凝污泥中回收明矾并将其重新用于化学强化一级处理（CEPT）工艺的可行性，从而使CEPT更具成本效益并有效回收资源（明矾）。在试验中研究了从混凝污泥中回收明矾的酸化方法的最佳条件和效率。结果表明，当明矾回收率达到最高水平84.5%时，污泥减少率为35.5%。结果表明，回收的混凝剂去除浊度、UV(254)和COD的能力分别为96%、46%和53%。结果证明，回收的混凝剂可用于CEPT，且回收的混凝剂去除污染物的效率与新鲜混凝剂相似。尽管在循环过程中会有一些物质富集，但它们对处理后废水的质量影响很小。实验证明，在水处理和化工废水处理中从混凝污泥中回收明矾是一种可取且具有成本效益的方法，然后可以将其循环用于CEPT，同时减少污泥体积。
