Author(s)

Ying Chi, Gang Zhou

Corresponding Author

Ying Chi

Abstract

In practical engineering application, because the washing effect of the screen demister is not ideal, ammonium sulfate particles are easy to stick to the screen and cause scaling and blockage, which not only leads to the increase of pressure drop in the absorption tower, but also leads to the shutdown of the whole system in serious cases. In practical engineering application, it is necessary to comprehensively consider the desulfurization efficiency and control the formation of "ammonia escape", and find the best operating parameters according to the actual situation on site. Aiming at the problem of low demisting efficiency of corrugated plate demister in common use at present, this paper studies the influence of ammonia escape and aerosol on CEMS and its countermeasures, so a new cosine demister is proposed and the demisting is optimized by numerical simulation. In this simulation, a boundary layer grid is set near the demister wall. The height of the first layer grid meets the grid scale factor, and the grid growth factor is 1.3, with a total of 6 layers. Under the same parameter setting conditions, compared with the original corrugated plate demister, the optimized cosine demister is 26.98% more efficient than the original corrugated plate demister when dealing with 5 μm particle size, which shows that the cosine demister has higher demisting efficiency when dealing with small particle size. Therefore, the optimized cosine demister has higher demisting efficiency than the original corrugated plate demister, and has more advantages in dealing with small-size particles, which can effectively reduce the escape of ammonium sulfate when it is used in ammonia single-tower desulfurization system.

Keywords

ammonia escape; aerosol; CEMS