基于加权磨煤机组合工况的喷氨格栅调整方法研究

Research on Adjustment Method of Ammonia Injection Grid Based on Weighted Coal Mill Combination Operation Condition

从已投运的燃煤机组SCR脱硝系统的实际运行情况看,SCR脱硝系统在运行过程中存在共性问题,如脱硝反应器出口与烟囱排放口的在线监测值相差较大、脱硝出口氨逃逸超标、两侧喷氨量实际值偏离计算值等。脱硝系统内浓度场不均是造成上述问题的主要原因之一,采取针对性喷氨方式是改进脱硝系统运行的有效手段。针对机组运行实际,开展一种基于加权磨煤机组合工况的喷氨格栅调整方法研究。研究结果显示,该方法可在不增加测试仪表、不对喷氨手动阀进行改造的前提下,实现各种变动工况的NOX有效控制。

In the actual operation of SCR denitrification system of coal-fired generating units, there are common problems in the operation of SCR denitrification system such as the large difference between on-line monitoring values of denitrification reactor outlet and chimney outlet, excessive ammonia escape at denitrification outlet, deviation of actual value of ammonia injection from calculated value. The uneven concentration area in denitrification system is one of the main reasons of the above problems, and targeted methods of ammonia injection is an effective means to improve the operation of denitrification system. Given the actual operation of the units, a method of ammonia injection grid adjustment based on weighted coal mill combination operation condition is developed. The research results show that this method can effectively control the NOX under various changing conditions without adding test instruments and modifying the manual valve for ammonia injection.