Comprehensive treatment method for chlorine-containing solid waste

Abstract

A comprehensive treatment method for chlorine-containing solid waste is characterized by comprising the steps: taking a solution containing magnesium chloride or / and magnesium sulfate as a washing liquid for the chlorine-containing solid waste, allowing obtained washed slag to return to be used as chlorination furnace charge, adding lime into the washing liquid, neutralizing to make impurities such as aluminum and iron precipitated and separated out, and filtering to obtain an impurity-removed post-liquid; and then adding sodium sulfate into the impurity-removed post-liquid, using a common ioneffect produced by chloridions, promoting chlorine to be precipitated and separated out in a form of sodium chloride solid, filtering to obtain sodium chloride crystals and a crystallization post-liquid, and allowing crystallized mother liquor to return to a washing process of the chlorine-containing solid waste for recycling, so as to realize the craft process of comprehensive utilization of thechlorine-containing solid waste. The method has the advantages of convenient operation, high operation efficiency, cleanliness and environmental protection, and is suitable for industrial applicationof treatment of the chlorine-containing solid waste.

Description

technical field [0001] The invention belongs to the fields of metallurgy and chemical industry, and in particular relates to a comprehensive treatment method for chlorine-containing solid waste. Background technique [0002] The chlorination metallurgical process produces a large amount of solid waste containing chloride, such as chlorination furnace gas dust slag, chlorination furnace bottom slag, chlorination waste salt slag, titanium tetrachloride precipitation mud, etc. Chlorides, especially metal chlorides, have relatively high solubility, such as aluminum chloride, ferric chloride, and calcium chloride, which all exceed 500g / L at room temperature. Most metal chlorides are deliquescent, so chlorine-containing solid waste is difficult to keep. Arbitrary stockpiling of chlorine-containing solid waste is likely to cause environmental pollution, so solid waste containing chloride is generally washed with water first, and then neutralized with sodium hydroxide for filtratio...

AI Technical Summary

Problems solved by technology

[0005] 2) The mixing volume ratio of the liquid after transformation and the high-concentration calcium chloride solution is 1:1~5, the mixing volume ratio is 1:1, the crystallization of sodium chloride is less than 50%, the mixing volume ratio is 1:5, the chlorine The crystallization of sodium chloride can be increased to about 75%, but the effective utilization rate of calcium chloride solution is too low;

[0006] 3) The solution containing calcium chloride is transformed by adding sodium sulfate first, and after the transformation, the solution is mixed with a high-concentration calcium chloride solution to crystallize and separate sodium chloride. The operation is cumbersome and the operation efficiency is low.