四角切圆锅炉冷灰斗局部结焦异常分析与对策

某厂仓储式制粉系统四角切圆锅炉多次发生炉膛4号角冷灰斗结焦、并上涨至运行平台标高的异常情况,降负荷运行打焦后,锅炉能恢复正常运行。锅炉运行中从看火孔观察炉膛燃烧器区域仅有轻微挂焦,测量发现炉膛温度基本均匀。冷态进入炉内检查发现卫燃带挂焦并不严重,排除了燃烧组织不当造成炉内局部结焦的可能。通过对电厂混煤掺烧方式的分析,认为炉前掺混不均匀、制粉系统投退造成混煤掺烧比例发生变化、4号角对应燃烧器燃用高结焦性的义马煤比例高是造成4号角多次结焦的主要原因,采取相应措施后,4号角结焦问题得到解决。

Analysis and Countermeasure to Anomalous Partial Coking in Furnace Hopper of Tangential Circle Firing Boiler

It is often occurred anomalous partial coking in furnace hopper of tangential circle firing boiler with storage pulverizing system. The coke residue volume could rise to height mark and the boiler could recover after decoking when load down. During running, only slight coking around the burners are found out through fire hole and the furnace temperature is even. After the boiler stops running, it is found the cokes stick to burner band are not serious and provided anomalous partial coking not from bad burning arrangement. By analyzing the coal-blending method, it is concluded that asymmetrical blending and blending ration change caused by startup or stopping pulverizing system are the main causes to form coke. The coke problem is solved after adopting corresponding measures.