不均匀喷氨系统在SNCR+SCR耦合脱硝技术中的应用

Application of Non-uniform Ammonia Injection System in Hybrid SNCR+SCR Denitrification Process

通过增加SCR梯度不均匀喷氨系统,克服SNCR烟气氨氮分布严重不均匀的明显缺点,也充分发挥了SNCR不需催化剂在炉内脱硝的优势。对比分析尿素水解、热解制氨的优缺点,通过实验研究优化喷氨格栅,强化了喷氨系统的适用性。分析了尿素水解SCR不均匀喷氨系统在实际工程中的效果,结果表明:尿素水解制氨结合SNCR+SCR耦合脱硝系统可以显著提高NOx的脱除效率;解决NH3/NOx分布不均匀问题。

To overcome the obvious shortcomings of uneven NH3-NOx distribution in selective non-catalytic reduction （SNCR） flue gas, and taking full advantages of SNCR system that does not require catalyst during denitrification, a hybrid SNCR＋SCR denitrification process was proposed by adding a non-uniform ammonia injection system. The advantages and disadvantages of urea hydrolysis and pyrolysis for ammonia production were compared and analyzed. The ammonia injection grid was optimized by experimental study, with focus on the applicability of the ammonia injection system. The effect of hybrid urea hydrolysis for ammonia and SCR non-uniform ammonia injection system in industrial application was analyzed. Results show that the the NOx removal efficiency could be significantly improved by coupling the urea hydrolysis for ammonia with the hybrid SNCR＋SCR denitrification system, thus solving the problem of uneven NH3-NOx distribution.