Method for processing waste acid generated in process of preparing acid from metal smelting fume

Abstract

The invention relates to a method for processing waste acid generated during preparing acid from fume generated in the smelting process of metal sulphide ore. In the method, the waste acid generated in process of preparing the acid from the metal smelting fume is processed by adopting a ferrous sulfate-lime neutralization method. The method comprises a sulfuration step and a neutralization step and is characterized in that a neutralizer used in the neutralization step is calcium carbide neutralizer slurry prepared from calcium carbide. In the invention, improvement is carried out aiming at the problems that in industrial application, the ferrous sulfate-lime neutralization method is large in the consumption of the calcium material lime of the neutralizer and high in processing cost; through fully utilizing the characteristic that the content of effective CaO in carbide slag is high, the carbide slag is used as a calcium material to replace the lime, thereby greatly reducing the cost, achieving the environment-friendly effect of treating the waste liquid by utilizing the waste slag, creating a novel way for use of calcium carbide and achieving the purpose of using wastes to treat wastes.

Description

technical field [0001] The invention relates to a method for treating by-products of metal smelting, in particular to a method for treating dirty acid produced by producing acid from metal sulfide ore smelting flue gas. Background technique [0002] During the smelting process of metal sulfide ore, a large amount of flue gas will be produced, which contains a large amount of sulfur dioxide and some harmful metal components. From the perspective of environmental protection and comprehensive utilization, in industrial production, generally according to the flue gas SO 2 Concentrations are different using different treatment processes, when SO 2 When the concentration is less than 2.5%, the method of flue gas desulfurization (FGD) is generally required for treatment. When SO 2 When the concentration is 2.5%~3.5%, SO 2 Flue gas can be directly used to produce sulfuric acid. There are currently two main processes, one is low-concentration SO 2 Unsteady conversion process, the...

AI Technical Summary

Problems solved by technology

Although the treatment effect of this process route has been improved, the process flow is complex, especially the calcareous material lime consumption as a neutralizing agent is large, resulting in high treatment costs, which has become the main factor affecting the industrial application of this process. Economic feasibility for industrial applications

[0010] On the other hand, in the production process of calcium carbide, after hydrolysis of calcium carbide to obtain acetylene gas, a large amount of waste residue with calcium hydroxide as the main component is produced. Carbide mud is calcium carbide slag with a water content higher than 50%, which has a large output and strong alkalinity. The price is cheap, and the effective CaO content in calcium carbide mud is about 60%, which can be used as a calcium substitute, but has not been used in this field