正压直吹式制粉系统防爆燃技术研究与应用

Research and Application of Explosion Proof Combustion Technology in Positive Pressure Direct Fired Pulverizing System

文章介绍了一种利用低温炉烟作为惰性介质的烟气再循环系统,在不影响直吹式制粉系统干燥出力的情况下,可有效控制制粉系统含氧量在17%以内,提高其防爆燃能力。以国内某电厂为例,合理地设计了烟气再循环系统,投运后制粉系统含氧量可控制在14%~16%,SCR入口NOx浓度水平下降约50 mg/m3,排烟温度略有升高,主、再热汽温度不受影响。在锅炉运行参数基本维持不变、安全性得以提升的情况下,较大幅度地降低了燃煤采购成本。

In this paper flue gas recirculation system using low temperature flue gas as inert medium is introduced,which can effectively control the oxygen content of the pulverizing system within 17%without affecting the drying output of the direct fired pulverizing system,and improve its deflagration resistance.Taking a domestic power plant as an example,the flue gas recirculation system is designed reasonably.After the operation,the oxygen content of the pulverizing system can be controlled at 14%~16%,the NOx concentration at SCR inlet decreases about 50 mg/m3,the exhaust gas temperature increases slightly,and the main and reheat steam temperatures are not affected.Under the condition that the boiler operation parameters are basically unchanged and the safety is improved,the coal procurement cost is greatly reduced.