摘要
煤的自燃倾向性多采用氧化动力学综合判定指数来评定。针对不同煤种得出的氧化动力学综合判定指数差异较大的问题,通过程序升温和红外光谱实验研究5种不同变质程度煤样的低温氧化特性,分析氧化动力学综合判定指数差异性的原因。实验结果表明,氧化动力学综合判定指数越低的煤样,温度为70℃时的O2含量越低,耗氧速率越高,低温下氧化能力越强。不同煤样的缓慢氧化进入快速氧化阶段的临界温度明显不同,致使交叉点温度差异很大。实验数据表明:褐煤临界温度为70℃,交叉点温度为151℃;长焰煤、气煤临界温度为100℃,交叉点温度分别为165.2℃、174.1℃;焦煤和无烟煤临界温度达到140℃,交叉点温度达到约200℃。通过分析煤氧化过程中的活性基团变化规律,进一步分析了氧化动力学综合判定指数,通过评定煤自燃倾向性等级能够诠释煤整个自燃过程的氧化特性。
The tendency of coal spontaneous combustion is generally evaluated by the comprehensive oxidation kinetics determination index.The comprehensive oxidation kinetics determination index obtained by different coal types is quite different.In this paper,the low temperature oxidation characteristics of five coal samples with different degrees of metamorphism were studied by programmed temperature rising and infrared spectroscopy experiments to explain the reasons for the comprehensive oxidation kinetics determination index.The experimental results show that the lower the comprehensive oxidation kinetics determination index,the lower the O2 contant at 70℃,the higher the oxygen consumption rate,and the stronger the oxidation ability at low temperature.The critical temperatures for slow oxidation of different coal samples entering the rapid oxidation stage are significantly different,resulting in large differences in crossing-point temperature.Experimental data show that the critical temperature of lignite is 70℃and the crossing-point temperature is 151℃;the critical temperatures of long-flame coal and gas coal are 100℃;the crossing-point temperatures are 165.2℃and 174.1℃respectively;the critical temperatures of coking coal and anthracite coal have reached 140℃.The crossing-point temperature also reached about 200℃.By analyzing the variation of active groups in the coal oxidation process,and further analyzing the comprehensive oxidation kinetics determination index,the oxidation characteristics of the whole spontaneous combustion process of coal can be interpreted by evaluating the coal spontaneous combustion tendency grade.
作者
王福生
戴可心
李紫旭
王建涛
WANG Fusheng;DAI Kexin;LI Zixu;WANG Jiantao(College of Mining Engineering, North China University of Science and Technology, Tangshan, Hebei 063210, China;Mining Development and Safety Technology Key Lab of Hebei Province, Tangshan, Hebei 063210, China)
出处
《中国科技论文》
CAS
北大核心
2020年第9期1005-1010,共6页
China Sciencepaper
基金
国家自然科学基金资助项目(51474086,51974128)
河北省自然科学基金资助项目(E2014209138)。
关键词
煤自燃
综合判定指数
低温氧化
活性基团
coal spontaneous combustion
comprehensive oxidation kinetics determination index
low temperature oxidation
active groups
