Arsenic treatment:With the development of industry, arsenic pollution has become a global environmental problem. In recent years, countries around the world are paying more and more attention to the control of arsenic pollution. Arsenic is one of the common pollutants and has great toxicity to human body. Arsenic is also a cumulative toxicant. Arsenic has also been found to be a carcinogenic substance. Arsenic pollution in the environment is mainly caused by three major industrial wastes, including pollution caused by arsenic-containing fumes, wastewater, waste gas, and slags emitted during the production of arsenic-containing metal ores in mining, roasting, smelting, chemical, coking, thermal power, paper making, and tanning. In this paper, the treatment technologies of arsenic-containing waste slag at home and abroad are reviewed as follows.

　　I. Arsenic treatment: stabilization technology

　　Arsenic treatment: stabilization process is the use of additives to change the engineering properties (such as permeability, compressibility, strength, etc.). .) .) .) .) Waste.) , even if the waste is converted into a non-movable solid. This process reduces the hazards of waste by turning hazardous contaminants into low-solubility, low-toxicity, low-mobility substances.

　　Arsenic treatment:Since soluble arsenic can form salt compounds with a variety of metal ions, using this property, arsenic-containing waste sludge and sludge should be pretreated, leaching out arsenic with hot water or acid-base solutions, and then stabilizing the leachate. In recent years, the common method used at home and abroad is the calcium and iron salt precipitation method.

　　(1) Arsenic treatment: calcium salt precipitation method

　　Calcium salt precipitation method is a common method of stabilization, low cost, simple process. The disadvantage of the calcium salt precipitation method is that the solubility of calcium salts is large, and the concentration of calcium must be far too much in order to reduce the concentration of arsenic to a low level, which requires the consumption of a large amount of flocculant, and the amount of residue after treatment is greatly increased.

　　(2) Arsenic treatment: iron salt precipitation method

　　Iron removal of arsenic is also a common method, and ferric chloride is often added to water as a flocculant. Under high pH conditions, when arsenic and iron are produced by this method, a large amount of iron hydroxide colloid is produced, and the arsenic salt and iron hydroxide in solution can be adsorbed and co-precipitated, thus obtaining a high rate of arsenic removal.