大型超超临界机组SCR系统问题探析

Analysis on SCR System Issues of Large Ultra Supercritical Unit

针对某电厂7000MW超超临界#1机组SCR系统脱硝出口的NOX数据与脱硫塔出口监测的NOX数据相差较大,为了控制SCR出口NOX浓度而大量喷氨的现象。本文通过试验研究,对该机组进行了SCR出口和脱硫塔出口NOX浓度分布测试,最终发现导致此现象的原因是A侧SCR入口喷氨存在较大不均匀性,进而导致了A侧SCR出口NOX浓度分布不均匀所致。通过改善A侧SCR入口喷氨均匀性,SCR出口与脱硫塔出口监测数据基本一致,同时还大幅降低了A侧SCR的喷氨量,取得了显著成效。本文研究成果对SCR脱硝系统的运行具有较强的指导意义。

In The lighe of NOx dates of SCR outlet and Desulfurization tower outlet are differ consider- ably of A 7000MW ultra supercritical #1 units, In order to control the SCR outlet concentration of NOx ,then injecting more ammonia. Through experiments in this paper,we test the NOx Concentration distribution of SCR outlet and Desulfurization tower outlet, Finally found the reasons of this phenome- non is A side SCR entrance ammonia existing inhomogeneity. By improving the A side SCR entrance ammonia spraying uniformity,The NOx dates of SCR outlet and Desulfurization tower outlet are agree- ment ,and substantially reducing the ammonia injection amount of A side SCR. This study Achieved re- markable results, so this paper has a strong guiding significance to the Operation of SCR system.