摘要
针对一台410t/h煤粉锅炉设计了再燃实施方案,提出煤粉颗粒群变氧浓度燃尽计算方法,计算分析再燃燃料比例、配风情况、再燃煤粉细度对煤粉炉内燃烧过程和飞灰含碳量的作用影响规律。结果表明,再燃实施方案设计合理,与现运行相比飞灰含碳量增加1.04%。为保证煤粉的燃尽度,燃尽区高度应大于7m,为煤粉提供大于1s的燃烧时间。主燃区过量空气系数、再燃区过量空气系数和再燃燃料比例在小范围内变化虽然影响到颗粒的燃烧放热过程,但对飞灰含碳量的影响不大。飞灰含碳量随燃尽区过量空气减少呈非线性显著增加,随再燃煤粉细度增加呈指数函数关系减少。再燃粉越细,飞灰含碳量随细度增加而降低越慢。
A ruburning retrofit scheme of a 410t/h pulverized-coal （PC） boiler was designed. And a method to calculating combustion efficiency of PC group in changing oxygen concentration was brought forward. Applied the method to the boiler, the effects of reburning fuel ratio, excess air ratio （α） and reburning coal fineness on combustion process and unburned coal in fly ash （UBC） were analyzed. The results show that the scheme is fitting and UBC increases 1.04% compared with that of the current operation. The burnout zone should be higher than 7 meters and provide combustion time more than 1 second in order to gain high combustion efficiency. Small change of α of main zone,α of reburning zone and rebuming fuel ratio affects UBC little through it affects combustion process. UBC increases evidently with α of burnout zone decreasing. UBC decreases exponentially with reburning PC fineness increasing. And reburning PC is finer, UBC increase is smaller.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2006年第18期116-120,共5页
Proceedings of the CSEE
关键词
热能动力工程
再燃
煤粉
飞灰含碳量
过量空气系数
thermal power engineering
reburning
pulverized coal
unburned coal in fly ash
excess air ratio
