降低循环流化床锅炉飞灰可燃物的探讨与实践

The technical transformation reducing fly ash combustibles in circulating fluidized bed boiler

针对2台燃用福建无烟煤的DG75/3.82-11型CFB锅炉所存在的飞灰可燃物含量较高的问题,通过分析福建无烟煤特有煤质特性、燃料颗粒特性、锅炉总体设计和运行调整工况是影响福建无烟煤在CFB锅炉中燃尽的主要因素。针对性采取优化筛分破碎系统、增强二次风的扰动穿透能力、提高旋风分离器的分离效率、改造回料风系统以减少返料偏流等措施;同时不断摸索CFB锅炉运行规律,完善和优化运行方式,应用锅炉燃烧优化控制系统实现CFB锅炉的自动优化控制运行。2台锅炉平均飞灰可燃物含量从2003年的22.17%降低到2009年第1季度的15.03%。

To solve the problem that higher levels of the combustible in fly ash on two DG75/3.82-11 type CFB boiler burning fujian-nthracite, by considered that the factors such as coal characteristics, fuel particles specification, boiler general design and operational condition are the major factors which influence the burn-out rate of Fujian anthracite coal. The technology measures such as optimizing screener and crusher system, enhancing secondary air＇s disturbance penetration, improving the efficiency of cyclone separation and retrofitting the return-charge wind system are adopted in order to raise the burn-out rate of Fujian anthracite in CFB boilers. At the same time, the regularity of CFB boiler operation are tried to find out, the operation mode are improved and optimized, the CFB boiler omnipotent optimize control systems are applied to achieve automatic optimal control. The combustible in fly ash of the two CFB boilers are reduced from 22.17% in 2003 down to 15.03% in the first quarter of 2009.