半焦点火特征时间的试验研究  

Experimental study on semi-coke particle ignition characteristics

作　　者：倪文婧[1] NI Wenjing(Tiandi Science & Technology Co.,Ltd.,Beijing 100013,China)

机构地区：[1]天地科技股份有限公司

出　　处：《煤炭科学技术》2019年第7期255-259,共5页Coal Science and Technology

基　　金：国家自然科学基金青年科学基金资助项目(51806220)

摘　　要：为了设计符合半焦燃烧特性的燃烧系统,在保证其系统安全性的前提,进一步提高其能源利用效率,通过新型高频振荡单分散煤粉给粉器,结合多元扩散火焰燃烧器技术,并配合煤粉全辐射信号分析试验方法,研究了温度和含氧量变化对半焦颗粒着火特性的影响。试验结果表明:当选择归一化信号强度0.1作为点火点时,半焦的特征点火时间在10ms量级;增加环境温度会加快半焦表面的化学反应速率,从而缩短半焦的点火时间,1800K时的点火时间小于1200K约4ms;增加同样会缩短半焦的点火时间,氧气体积分数为10%时的点火时间较20%时降低了约2ms;由于点火特征时间改变带来的燃烧器特征尺寸变化约为0.15m。In order to design a combustion system that meets the semi-coke combustion characteristics,the energy utilization efficiency is further improved on the premise of ensuring the safety of the system.In this paper,a multi non-premixed flat-flame Hencken burner system combined with a vibrated de-agglomeration particle feeder was used to investigate the effect of ambience temperature and the oxygen fraction on the semi-char ignition characteristic time.The experimental results shows when the normalized signal strength of 0.1 is selected as the ignition point,the characteristic ignition time of the semi-coke is about 10 ms;Increasing the ambient temperature accelerates the chemical reaction rate of the semi-coke surface and shortens the ignition time,and ignition time at 1 800 K is less than 1 200 K for about 4 ms;the increase will also shorten the ignition time of the semi-coke.The ignition time at an oxygen concentration of 10%is reduced by about 2 ms from 20%;the size of the burner changes due to the change in the ignition characteristic time is about 0.15 meters.

关 键 词：半焦 光学测量 点火特征时间 非均相燃烧 

分 类 号：TD94[矿业工程—选矿]