The Research Of Dynamics On HCl Removal From Blast Furnace Top Gas

The development of iron and steel industry has been promoted greatly by the development of blast furnace pulverized-coal injection technology, the promotion of cloth-bag dusting technology, and the application of TRT technology of blast furnace.However, the effects of HCl gas has gradually emerged on the whole process of blast furnace production. Mainly include the corrosion in gas pipeline, the slagging on hot-air furnace regenerator checker brick, the packing on cloth-bag dusting box wall, and the fouling on TRT unit’s leaf, which affected the normal operation of blast furnace production seriously. Therefore, the study about HCl removal of blast furnace gas is of important significance.Based on the mathematical model of the dechlorination reaction dynamics, can get a conclusion that the reaction of dechlorination agent and HCl gas is mainly controlled by chemical reaction, and the effect of product layer diffusion can not be ignored.The experiment studied the effects of gas components on HCl removal process in blast furnace top gas, such as CO, CO2, N2 and H2, both in clean conditions and in dusty conditions, by the gas removal experiment device, and further studied the effect of dust content on HCl removal process in blast furnace top gas. Main conclusions are drawn as follows: In blast furnace gas, when the content of CO2 increased, the breakthrough time and penetrated-chlorine capacity reduced, the dechlorination efficiency is getting worse;when the content of CO2 and the content of N2 increased, the breakthrough time and penetrated-chlorine capacity increased, the dechlorination efficiency is getting better; but the content of H2 have no significant effect on the breakthrough time and penetratedchlorine capacity. The effect of gas composition on the breakthrough time and penetrated-chlorine capacity in dusty conditions is similar to which in clean conditions.But the breakthrough time and penetrated-chlorine capacity in dusty conditions is significantly higher than which in dust-free conditions. The furnace dust has great influence on the speed of dechlorination reaction, when the dust content in blast furnace gas at 20g/m3~30g/m3, the dechlorination efficiency is relatively better. The best implement place of the HCl gas removal device for blast furnace top gas should be site after the gravity precipitator and before the cloth-bag dusting.