超低排放电站锅炉SCR脱硝装置的故障诊断及运行优化研究

摘要

The operation control of SCR becomes more difficult after the ultra-emission retrofits.Some problems,such as,NOx emission exceeding the guideline standard and extensive air pre-heater blocking,are much easier to happen.Generally,these problems are treated with diagnosis and optimization experiments of SCR (DOES for short).However,the effectiveness of DOES is directly related to the state of the SCR equipments:on the condition of no equipment defects,DOES tends to achieve good results,otherwise,if severe defects existing in the equipments,the effectiveness of DOES' is poor,and the improvement on the original bad operation condition is limited.In this situation,the DOES functions is more like the fault diagnosis,which is able to find out the most possible causes for the SCR performance decreasing,and provide the technical evidence for the owner to take effective treatment to deal with the problems.%超低排放改造后脱硝装置运行控制难度加大,易出现NOx排放不达标或空气预热器堵塞加剧等问题,一般通过SCR诊断优化试验进行处理,而试验的效果与脱硝装置的设备情况直接相关:在设备基本无缺陷情况下,诊断优化试验往往能够取得良好的效果;而当系统的缺陷较严重时,诊断优化试验则效果不佳,仅能在一定程度上改善原有恶劣工况,此时试验的作用更多地体现为故障诊断,能够较为准确地排查出引起脱硝装置性能下降的可能的原因,为业主采取有针对性的解决措施提供技术依据.