Method for adding distilled ammonia vapor into desulfurized solution in ammonia desulphurization process and special equipment thereof

Abstract

The invention provides a method used for adding a desulfurization solution into ammonia steam during ammonia desulfurization process and special equipment thereof, belonging to the field of purification technique of coke oven gas. The method comprises the steps as follows: part of circular desulfurization solution in the ammonia desulfurization process is injected in an injection tower so as to absorb, condense and cool the ammonia steam which is condensed from the top of a ammonia still, so as to lead the ammonia to be transferred into the desulfurization solution; the ammonia stream is absorbed by the desulfurization solution to form tail gas which is directly exhausted; the desulfurization solution with the ammonia absorbed is sent back in a desulfurization solution circulation system by pipelines; the residual desulfurization solution of the desulfurization solution circulation system is sent into a vacuum evaporation salt extractor, thus recovering the salt in the desulfurizationsolution; and the separated water generated by the vacuum evaporation salt extractor is sent into an ammonia disposal system. The method and the equipment have simple flow, are beneficial for improving the ammonia streaming efficiency, reduce the loss of the ammonia steam, and can keep the water balance of the desulfurization solution.

Description

technical field [0001] The invention belongs to the technical field of coke oven gas purification, and relates to a process and equipment related to ammonia desulfurization, in particular to a method for adding ammonia steam to desulfurization liquid in the ammonia desulfurization process and special equipment thereof. Background technique [0002] In the coke oven gas purification process of the coking plant, there is a process using ammonia desulfurization. In order to maintain a certain desulfurization efficiency and when the gas produced by high-sulfur coal coking contains high hydrogen sulfide, the desulfurization liquid needs to be maintained relatively high. For high liquid ammonia concentration, after cooling the ammonia vapor evaporated from the remaining ammonia water, add it to the desulfurization liquid. This process must solve three key problems: first, the ammonia vapor after being split and shrunk at the top of the ammonia distillation tower must be condensed ...

AI Technical Summary

Problems solved by technology

This process must solve three key problems: first, the ammonia steam that has been split and shrunk at the top of the ammonia distillation tower must be condensed and cooled, and then added to the desulfurization liquid; The concentration of ammonia is relatively high and cannot be discharged directly. It must be led to the gas equipment (usually a desulfurization precooling tower), which makes the tower pressure of the ammonia distillation tower higher and reduces the efficiency of ammonia distillation; third, due to the Generally, it contains 80-85% water, which puts forward requirements for the water balance of desulfurization liquid, and corresponding technical means for water balance of desulfurization liquid are required

However, since the ammonia-based desulfurization liquid is a high-concentration pollutant and cannot directly enter the biochemical treatment device, the environmental pollution caused by direct discharge is quite large.

If it is added to the mixed coal for treatment, it is quite uneconomical, which increases the moisture content of the mixed gas, increases the heating gas consumption of the coke oven, and most of the sulfur returns to the gas that needs to be purified, and returns to the desulfurization process. Increased desulfurization load, resulting in an ineffective cycle of sulfur

Images