Method for removing chlorine radicals and sulfate radicals in zinc hypoxide raw material

Abstract

The invention discloses a method for removing chlorine radicals and sulfate radicals in a zinc hypoxide raw material, which comprises the following steps: A, mixing and reacting raffinate containing chlorine radicals, sulfate radicals, ammonium radicals and a small amount of metal ions with a calcium chloride solution to obtain mixed turbid liquid, and carrying out solid-liquid separation on the mixed turbid liquid to obtain calcium sulfate solid and calcium sulfate supernate; B, drying the calcium sulfate solid to obtain calcium sulfate dihydrate; C, adding lime into the calcium sulfate supernatant through a lime feeding system, and carrying out pre-deamination to obtain a deamination liquid; and D, pumping the deamination liquid into a deamination tower, carrying out steam stripping deamination on the deamination liquid, and collecting obtained ammonia gas through an ammonia gas absorption tower to obtain regenerated ammonia water. The method for removing the chlorine radicals and the sulfate radicals in the zinc hypoxide raw material adopts the structure, is simple in process, short in flow and high in operability, can solve the problem of enrichment of the chlorine radicals and the sulfate radicals in the zinc hypoxide raw material comprehensively recovered by a traditional process, and reduces the production cost.

Description

technical field [0001] The invention relates to the technical field of hydrometallurgy, in particular to a method for removing chloride radicals and sulfate radicals in secondary zinc oxide raw materials. Background technique [0002] In hydrometallurgy, the mainstream process of raw material leaching is acid leaching. However, acidic leaching requires high acidity, and a large amount of non-target metals will also be leached into the solution. In the subsequent purification process, metal ions such as Fe ions in conventional treatment will form colloids, making the solution basically impossible to filter Or replacement purification consumes a large amount of acid. Therefore, more and more companies start to use chlorine salt leaching. The obvious advantage of ammonium salt leaching is that iron ions will not be leached out of the solution, and the solution can maintain a high pH value. During replacement purification, the consumption of replacement products can be signifi...

AI Technical Summary

Problems solved by technology

[0003] The types of raw materials used in wet leaching are various, and it is unavoidable that soluble sulfate radicals and chloride salts enter the leaching system. After entering the production system, chloride salts will continue to be enriched with the continuous entry of raw materials. Due to the chloride ion itself It is highly corrosive to metal equipment. At the same time, chlorine salts generally have a large solubility and are also very sensitive to temperature changes. Therefore, when the solution temperature fluctuates during the production process, it is easy to get out of the solution. Precipitation clogs pipes and equipment

In addition, when chlorine radicals enter the electrowinning system, traditional sulfate electrowinning will produce chlorine gas that pollutes the environment and corrodes equipment, reducing electrowinning efficiency. The enrichment of sulfate radicals causes the precipitation of metal salts in the solution, resulting in pipeline blockage and low equipment efficiency.

Many enterprises have to restrict the use of secondary zinc oxide raw materials containing chlorine and high sulfate, resulting in an increase in the price of low-chlorine and low-sulfate raw materials in the market

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