SCR尿素热解炉优化的数值模拟

Numerical simulation on optimization of SCR urea pyrolysis furnace

以采用选择性催化还原法(SCR)的尿素热解炉为研究对象,对炉内烟气速度场、氨气浓度场进行数值模拟,结果表明烟气入口的弯管结构造成热解产物(NH3)浓度在一定范围出现不均匀。针对这一问题,分别采用添加整流器、增加烟气引入管长度、同时添加整流器和增加烟气引入管长度的三种改进方案。结果显示:同时添加整流器和增加烟气引入管长度的改进方案效果最好,有利于氨气浓度分布均匀,提高脱硝效率。

The urea pyrolysis furnace using selective catalytic reduction(SCR)was taken as research subject, the numerical simulation of the flue gas velocity field and ammonia concentration field in the furnace showed that heterogeneous concentration of pyrolysis products(NH3) at the bent inlet of flue gas pipe. To solve this problem, three improved schemes of adding a rectifier, increasing the length of the flue gas introduction tube, adding a rectifier at the same time, and increasing the length of the flue gas introduction tube were respectively adopted. The results showed that the improved scheme of adding rectifier and increasing the length of flue gas introduction tube is the best scheme, which was beneficial to the uniform distribution of ammonia concentration and improve the denitration efficiency.