A kind of waste acid recycling and recovery method

Abstract

The invention discloses a resource recovery and treatment method of polluted acid. The method comprises the following steps: 1) adding a vulcanizing agent to the polluted acid, first recovering valuable metals in the polluted acid, and then removing arsenic; 2) Under the action of an electric field, the treated polluted acid is electrodialyzed to separate fluoride ions, chloride ions and sulfate ions by using a selective separation ion membrane, and the dilute sulfuric acid obtained after the removal of fluoride ions and chloride ions is reused in production; 3 ) Step 2) The obtained high-fluorine wastewater containing fluoride ions and chloride ions is reused or discharged after neutralization treatment+adsorption treatment. The recovery rate of valuable metals in the invention reaches over 90%, the waste acid after treatment reaches the reuse standard, and the generation of hazardous waste is reduced by over 90%.

Description

technical field [0001] The invention belongs to the field of environmental protection hazardous waste treatment methods. Specifically, the invention relates to a resource recovery and treatment method of polluted acid, which is used for resource recovery and treatment of polluted acid produced in nonferrous metal smelting, especially for copper, lead, zinc, Treatment of dirty acid in nickel and other smelting industries. Background technique [0002] Flue gas from non-ferrous metal smelting must be washed and purified before acid production. During this process, heavy metals such as arsenic, lead, and cadmium, fluoride, and chloride are particularly easily absorbed by water and dilute acid. Dirty acid with chlorine. Because the polluted acid contains heavy metals, especially fluorine and chloride ions, it cannot be reused. At present, the methods of lime neutralization, HDS neutralization, and sulfide-lime neutralization are mainly used for the treatment of polluted acid wa...

AI Technical Summary

Problems solved by technology

Because the polluted acid contains heavy metals, especially fluorine and chloride ions, it cannot be reused. At present, the methods of lime neutralization, HDS neutralization, and sulfide-lime neutralization are mainly used for the treatment of polluted acid wastewater, and the following problems exist: ① Pollution Valuable metals are transferred to the waste residue during the acid treatment process, which is difficult to recycle. At the same time, a large amount of hazardous waste is generated, the disposal cost is high, and it is easy to cause serious secondary pollution; ② The loss and waste of acid resources; ③ Due to the large amount of lime milk , which not only results in high cost of sewage treatment, but also makes the hardness of the effluent too high, which seriously affects the reuse of wastewater

In this patent application, 1) there are many pretreatment steps for the removal of arsenic and heavy metals by polluted acid, and valuable metals cannot be recovered; 2) the ion exchange method is usually used in occasions with relatively good water quality, and ion exchange is used to remove pollutants under strong acid conditions. It is very difficult to realize the technology of fluorine and chlorine in acid

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