粒径对福建无烟煤在CFB锅炉中燃尽的影响  

Influence of the Particle Size of Fujian Anthracite Coal on Its Burnout in CFB Boiler

作　　者：庄煌煌[1,2] 何宏舟[3,2] 李志伟[3,2] 邹峥[3,2] 

机构地区：[1]集美大学轮机工程学院,福建厦门361021 [2]福建省清洁燃烧与能源高效利用工程技术研究中心,福建厦门361021 [3]集美大学机械与能源工程学院,福建厦门361021

出　　处：《过程工程学报》2013年第5期846-850,共5页The Chinese Journal of Process Engineering

基　　金：福建省科技创新平台资助项目(编号:2009H2006)

摘　　要：建立了福建无烟煤细颗粒燃烧模型，计算了其在容量35讹循环流化床锅炉炉膛内的燃尽时间和一次通过炉膛的停留时间，分析了不同粒径煤颗粒在不同燃烧温度和不同烟气流速时在CFB锅炉内的燃尽时间和停留时间的变化差异．实验研究了福建无烟煤粒径对飞灰碳含量的影响及燃尽的影响．结果表明，细煤颗粒的燃尽时间与停留时间均随粒径增大而增长，但燃尽时间增幅更明显，颗粒一次通过炉膛完全燃尽的临界粒径约为0．15mm；粒径越大的颗粒其停留时间和燃尽时间对烟气流速和燃烧温度变化越敏感；无烟煤入炉粒径明显影响CFB锅炉飞灰含碳量，选用粒度为3-8mm的偏粗颗粒为宜．A simplified heat transfer and combustion model for the combustion of fine anthracite coal particles in a circulating fluidized bed （CFB） boiler was established. The burnout time and residence time （one time through furnace） of a single fine coal particle in the CFB boiler were calculated, and the effects of particle sizes of Fujian anthracite on both of time at different combustion temperatures and flue gas velocities examined. Besides, industrial combustion experiments of Fujian anthracite were conducted in a 35 t/h CFB boiler to test the effect of coal particle size on the carbon content of fly ash. It is shown that the particle size has a significant effect on the burnout of coal in the boiler. With rising of the coal particle size, both the burnout time and residence time increase, but the former increases more faster than the latter, the critical particle size of Fujian anthracite in burnout, which is burnt out once through the furnace, is about 0.15 mm. As the particles are coarser, their residence time is more sensitive to the flue gas velocity, while their burnout time to the combustion temperature. For those CFB boilers with small capacity for combustion of Fujian anthracite, in order to reduce the carbon content in fly ash, using the coarse coal particles with the sizes of 3-8 mm is suitable.

关 键 词：循环流化床锅炉 福建无烟煤 粒径 燃尽 停留时间 

分 类 号：TK229.66[动力工程及工程热物理—动力机械及工程]