关键词: 火电厂, 烟气脱硝, SCR, 故障诊断, 优化, 空气预热器

Abstract: The operation control of SCR becomes more difficult after the ultra-emission retrofits. Some problems, such as, NO_x 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.

Key words: thermal power plant, flue gas denitrification, SCR, fault diagnosis, optimization, air pre-heater