污泥热解残渣制备聚合氯化铝的实验研究＊

含铝污泥热解或焚烧残渣制备聚合氯化铝的研究,有利于实现污水处理过程投加的铝盐絮凝药剂的回收与高效循环利用,减少污染物排放和资源消耗。针对辽河油田欢三联稠油污水处理污泥的热解残渣具有较高铝含量的特点,开展采用盐酸进行铝溶出及制备聚合氯化铝的实验研究。结果表明:焙烧温度为700～750℃,焙烧时间控制在1h即可。将经过焙烧活化的残渣在常温下进行酸溶,酸溶时间为2～5h,选用25%～30%盐酸,氧化铝与盐酸的摩尔比为1∶1.0～1∶1.2为宜。将溶出的铝溶液制备聚合氯化铝,在常温下采用CaO粉末来调节pH值为3.5,聚合反应时间为1d,即可得聚合氯化铝溶液。

Experimental Research on Preparation of Polyaluminium Chloride from Sludge Pyrolysis Residues

Studies on preparation of polyaluminium chloride by pyrolyzing aluminized sludge or incinerating residue are conducive to recovering pharmaceutical aluminum flocculation,recycling efficiently,and reducing pollutant emissions and resource consumption.Due to the characteristic of pyrolysis residue with high aluminum content in Liaohe Oilfield,we carried out an experimental study on hydrochloric acid dissolution and preparation of polyaluminium chloride.The results showed that the calcination time should be controlled within 1 h when the calcination temperature was 700～750 ℃.Then the calcined residue was dissolved by 25%～30% hydrochloric acid with 2～5 h at normal temperature.The proper molar ratio of alumina and hydrochloric acid was 1:1.0～1:1.2.Lastly the polyaluminium chloride could be prepared through adjusting the pH of alum solution to 3.5 with lime power at normal temperature,and the polymerization time was 1 d.