With the rapid development of early industry, there are many kinds of sewage, which causes a headache in metallurgy. Because it is difficult to treat the sewage according to the specific conditions of each industry, polyaluminium chloride is used as the matrix, mixed with other chemicals, and mixed into composite PAC. The sewage can be treated with surprising results.

　　，由于我们的聚合氯化铝分子结构大，吸附能力强，用量少，处理成本低。其溶解性好，活性高，在水体中凝聚形成的矾花大，沉降快，比其他无机絮凝剂净化能力大2-3倍。聚合氯化铝适应性强，受水体PH值和温度影响小，原水净化后能达到引用水标准，处理后水质中阳、阴离子含量低，有利于离子交换处理和高纯水的制备。

　　First of all, because of the large molecular structure, strong adsorption capacity, low dosage and low treatment cost of polyaluminium chloride. It has good solubility and high activity. The alum flower formed by coagulation in water body is large, settling is fast, and its purification capacity is 2-3 times larger than other inorganic flocculants. Polyaluminium chloride has strong adaptability and is little affected by the pH value and temperature of water body. After purification, the raw water can reach the national standard of drinking water. The content of cation and anion in the treated water is low, which is conducive to the preparation of ion exchange treatment and high-purity water.

　　然后，聚合氯化铝腐蚀性小，操作简便，能改善投药工序的劳动强度和劳动条件。当聚合氯化铝絮凝剂和聚丙烯酰胺进行配合使用的时候，我们应视不同的水质按照先后顺序投加，而其药量也要通过试验确定。其实，聚合氧化铝也可以单用，但其比PAC高，效果不比加PAC的水质差，当然要分水质情况而定。如果处理水要排放的话，丙烯酰胺单体带有毒性也是需要考虑的一个问题。悬浊物比较多的时候一般单用PAM也可以了。

　　Then, the polyaluminium chloride is less corrosive and easy to operate, which can improve the labor intensity and working conditions of the dosing process. When polyaluminium chloride flocculant and polyacrylamide are used together, we should add them in order according to different water quality, and the dosage should also be determined by test. In fact, Polyalumina can also be used alone, but its price is higher than that of PAC, and the effect is not worse than that of PAC. Of course, it depends on the water quality. If the treated water is to be discharged, the toxicity of acrylamide monomer should also be considered. When there is a lot of suspended matter, PAM alone can also be used.