尿素SCR催化反应中气态氨供给速率计算方法研究

Study of Gaseous Ammonia Supply Rate Calculation Method for Urea-SCR Catalytic Reactors

在研究选择性催化还原(SCR)反应的气态氨平衡关系及催化剂动态转化效率-储氨量关系的基础上,提出了一种基于催化剂台架试验-性能模拟计算结果对比的台架试验条件下SCR催化反应体系中气态氨供给速率、尿素存积速率的定量计算方法。使用该方法针对特定SCR台架试验数据进行的计算,结果表明:在催化剂入口排气温度300℃、空速40 000h-1时,尿素水溶液分解存在一定程度滞后,但最终分解较为完全。这为研究SCR台架评价中尿素水溶液的分解条件及其对评价结果的影响提供了工具。

Based on the research of the gaseous ammonia equilibrium equation in S C R reaction as well as the functional relationship between S C R dynamic conversion rate and ammonia storage amount, a quantitative calculation method for gaseous ammonia supply rate and urea deposit rate is proposed by comparing the catalyst bench evaluation and performance simulation calculation. Using this method, the calculation of specific bench test data shows that there is a certain degree of delay in the decomposition of urea solution at a catalytic converter inlet temperature of 300 ℃ and space velocity of 40 000 h^-1 , but the final decomposition is quite complete. This study provides an effective tool for analyzing the decomposition conditions of urea solution and its effect on engine bench evaluations.