动态喷氨格栅在SCR脱硝工艺中的应用研究

Research of dynamic ammonia injection grid on SCR denitrification process

SCR工艺脱硝效率与NH3/NOx摩尔比,催化剂床层上方气流分布,NH3与烟气混合程度密切相关。借助物理模型模拟某电厂300 MW中型机组尾部SCR烟气脱硝反应器,对动态喷氨格栅对催化剂床层上下方测试断面Ⅰ、Ⅱ的烟气流速偏差和NH3(CO2)的浓度偏差进行测试。结果表明:Ⅰ断面最大和最小烟气流速分别为4.47 m/s和3.75 m/s,最大偏差16.11%;Ⅱ断面最大和最小烟气流速分别为4.21 m/s和3.42 m/s,最大偏差18.76%。I断面最大和最小CO2浓度分别为4.1%和3.4%,最大偏差为17.07%;Ⅱ断面最大和最小CO2浓度分别为4.0%和3.2%,最大偏差20.0%,因此采用动态喷氨格栅对SCR反应器的高效运行具有积极作用。

The denitrification rate of SCR process relates to NH3/NOy mole ratio, smoke flow distribution on catalyst bed and mixing degree of NH3 ＆ smoke. It utilized physical model simulated SCR denitrification reactor which is part of 300 MW middle - sized generator. Then it installed dynamic ammonia injection grid and measured the smoke flow distribution deviation and NH3 （CO2） concentration deviation on Ⅰ , Ⅱ sections which located at above and bottom of catalyst bed respectively. The result indicates that., the maximum and minimum smoke velocity of I section is 4.47 m/s and 3.75 m/s, the deviation is 16. 11%. The maximum and minimum smoke velocity of Ⅱ section is 4.21 m/s and 3.42 m/s, the deviation is 18.76%. The maximum and minimum NH3 （CO2） concentration of Ⅰ section is 4.1% and 3.4%, the deviation is 17.07%. The maximum and minimum NH3 （CO2 ） concentration of Ⅱ section is 4.0% and 3.2%, the deviation is 20.0%. Consequently, the dynamic ammonia injection grid is beneficial to the efficiently running of SCR denitrification reactor.