A kind of pretreatment method of vacuum potassium carbonate gas desulfurization waste liquid

Abstract

The invention relates to a pretreatment method for a desulfurization waste solution by vacuum potassium carbonate coal gas. The technical scheme is that the pretreatment method comprises the following step: collecting the desulfurization waste solution in a liquid storage tank (1) and acidifying the desulfurization waste solution in the liquid storage tank (1) by virtue of an acidifying tower (7), wherein hydrogen sulfide and hydrogen cyanide generated by acidification and acid gas from a vacuum potassium carbonate desulfurization regeneration tower enter a Claus oven together to recover sulfur, and the acidified desulfurization waste solution is incorporated into a bio-adjustment pool of a bio-treatment system of coking phenol cyanogen wastewater and the pH value is adjusted to 7.0-8.5 for bio-treatment; the acidification comprises the following steps: firstly, adding acids into the acidifying tower (7) through an acid groove (4); then spraying the desulfurization waste solution to the acidifying tower (7) through a sprayer (6) by using a circulating pump (3); introducing compressed air into the acidifying tower (7) by using an air compressor (2); and operating acidification in an intermittent mode. The pretreatment method provided by the invention treats the desulfurization waste solution from the source and has the characteristics of being short in process flow, simple in process, less in equipment, less in investment, low in operating cost and free of secondary pollutants.

Description

technical field [0001] The invention belongs to the technical field of desulfurization waste liquid treatment. Specifically relates to a pretreatment method for vacuum potassium carbonate gas desulfurization waste liquid. Background technique [0002] The vacuum potassium carbonate desulfurization process is a wet desulfurization technology widely used by large coking enterprises in my country in the field of gas purification. Coke oven gas enters the desulfurization unit after initial cooling, electric tar capture, final cooling, and benzene washing. The vacuum potassium carbonate method uses potassium carbonate as the absorption liquid, and the potassium carbonate solution absorbs the H in the coke oven gas in the absorption tower. 2 S, HCN and CO 2 After waiting for the acid gas, it becomes a desulfurization rich liquid, and the desulfurization rich liquid is sent to the regeneration tower, and the H in the desulfurization rich liquid 2 S and HCN-based acid gases are ...

AI Technical Summary

Problems solved by technology

[0003] There is no mature treatment technology for desulfurization waste liquid by vacuum potassium carbonate method. The main treatment methods are: regularly discharge the desulfurization waste liquid into the coal blending system. The disadvantage of this method is that the sulfide, thiocyanate, Secondary salts such as thiosulfate enter the coking system, affecting coke quality and corroding coke oven equipment; other methods, such as adding precipitants or oxidants to desulfurization waste liquid, can reduce the sulfide and Cyanide content, but the treatment process is complicated, the process is cumbersome, and the operating cost is high

So far, there is no method for controlling the waste liquid of vacuum potassium carbonate desulfurization from the source

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