300 MW机组喷氨优化分析及评估

Optimization Analysis and Evaluation of Ammonia Injection for 300 MW Unit

某300 MW机组由于煤质变化及负荷波动等因素,存在SCR脱硝系统出口NOx质量浓度偏差较大的问题,为了保证NOx排放量不超标而过量喷氨,加剧了下游空气预热器硫酸氢铵的生成。针对该机组SCR脱硝系统进行喷氨优化调整试验,通过多次优化调整,A侧SCR脱硝反应器出口NOx质量浓度相对标准偏差由摸底试验工况的51.7%降低至8.4%,B侧SCR脱硝反应器出口NOx质量浓度相对标准偏差由摸底试验工况的28.0%降低至9.8%,A、B侧平均氨逃逸体积分数由调整前的2.10×10^(-6)、3.10×10^(-6)降低至0.30×10^(-6)、1.83×10^(-6),喷氨优化效果良好。

Due to the change of coal quality and load fluctuation for a 300 MW unit,the NOx concentration deviation at the outlet of SCR denitration system is large.To ensure the NOx emission does not exceed standard,excessive ammonia injection inevitably aggravates the of ammonium bisulfate generation in the downstream air preheater.The ammonia injection optimization adjustment test was carried out for the SCR denitration system of the unit.Through multiple optimization and adjustment,the relative standard deviation of NOx concentration at the outlet section of SCR denitration reactor on the A side was reduced from 51.7%to 8.4%under the test condition,and the relative standard deviation of NOx concentration at the outlet section of SCR denitration reactor on the B side was reduced from 28.0%to 9.8%under the test conditiont,and the average ammonia escape concentration at the A and B sides was reduced from 2.10×10^(-6)and 3.10×10^(-6)before adjustment to 0.30×10^(-6)and 1.83×10^(-6),showing the optimization effect of ammonia injection was good.