Analysis and Discussions on the Nonuniformity Problem of SCR Denitration Equipment NO x Concentration Distribution in a 600MW Coal-fired Unit

Combining with an engineering example, from the aspects of SCR inlet NOx concentration distribution, flue gas velocity uniformity, ammonia injection valve opening, ash deposit, abrasion and flue arrangement, the uniformity problem of SCR denitration equipment outlet NOx concentration distribution is analyzed and discussed in a 660MW coal-fired unit. The results show that the uneven distribution of NOx concentration is caused by the combined action of many factors. In the cause analysis and solution formulation, the influence factors need be overall consideration. By adjusting the ammonia injection valve opening, the uniformity of SCR outlet NOx concentration increases by about 30%, the performance of SCR denitration equipment is obviously improved. At the same time, rationalization proposals and solution measures for the improvement of outlet concentration uniformity are given in order to ensure the safe and stable operation of denitration equipment.