摘要
建立了煤粉燃烧率通用模型,模型可以根据煤粉的工业分析值计算燃烧动力学参数并预测煤粉燃烧率.通过对比前人的实验数据,验证了模型的准确性,同时研究了影响高炉煤粉燃烧率的若干因素.研究结果表明:在高炉喷煤过程中,煤粉颗粒在2 ms左右就可以达到热风速度,由于煤粉颗粒在直吹管内停留时间短并且温度较低,因此在直吹管内煤粉不会发生燃烧.煤粉进入风口回旋区后,挥发分瞬间全部析出,并且颗粒粒径越小,挥发分开始析出时间越早.降低煤粉粒径和增加氧气体积分数均有利于提高煤粉燃烧率.氧气体积分数每增加1%,燃烧率提高2%.随着喷煤量的增加,煤粉燃烧率逐渐降低.当提高煤粉喷吹量时,为了保证较高的燃烧率,实际操作过程中应提高富氧率并适当降低煤粉粒径.
A general model of pulverized coal combustion ratio was put forward, which can calculate the kinetic parameters and combustion ratio based on coal industrial analysis. The accuracy of this model was verified by comparing with previous experimental data. Some factors influencing the coal combustion ratio were discussed. It is found that during the process of pulverized coal injection, the pulverized coal particle can reach the velocity of hot blast within 2 ms. In the blowpipe, due to the pulverized coal particle with short residence time and lower temperature, combustion reaction does not occur. When the pulverized coal particle enters into the race-way, the volatile is released instantly. The smaller the coal diameter is, the earlier the volatile will be released. The coal combustion ratio can be improved by decreasing the coal diameter or increasing the oxygen enrichment. When the oxygen enrichment increases 1%the combustion ratio increases about 2%. With increasing coal injection rate, the coal combustion ratio decreases. Therefore, when the coal injection rate increases, we should increase the oxygen enrichment and decrease the particle diameter appropriately to maintain the high combustion ratio.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2014年第2期226-234,共9页
Journal of University of Science and Technology Beijing
基金
国家自然科学基金资助项目(61271303)
关键词
高炉
煤粉燃烧
数学模型
因素分析
blast furnaces
coal combustion
mathematical models
factor analysis
