不同温度下预氧化煤自然发火特性研究  

Study on spontaneous combustion characteristics of preoxidized coal at different temperatures

作　　者：李高静 董宪伟 王福生[1,2] 周建 LI Gaojing;DONG Xianwei;WANG Fusheng;ZHOU Jian(School of Mining Engineering,North China University of Science and Technology,Tangshan,Hebei 063210,China;Key Laboratory of Mining Development and Safety Technology of Hebei Province,Tangshan,Hebei 063210,China;Donghuantuo Mining Branch,Kailuan(Group)Co.,Ltd.,Tangshan,Hebei 064002,China)

机构地区：[1]华北理工大学矿业工程学院,河北唐山063210 [2]河北省矿业开发与安全技术重点实验室,河北唐山063210 [3]开滦(集团)有限责任公司东欢坨矿业分公司,河北唐山064002

出　　处：《中国科技论文》2024年第7期752-759,共8页China Sciencepaper

基　　金：国家自然科学基金资助项目(51974128)。

摘　　要：为研究采空区遗煤自然发火问题,将东欢坨气煤分别进行80、160、230℃预氧化处理,以此研究氧化煤自燃特性的差异。采用低温氮气吸附实验、程序升温-气相色谱联用实验、热重(thermogravimetric,TG)实验联合分析,对不同预氧化温度下煤孔隙变化及自燃氧化前期的特征气体和活化能变化进行研究,以此探讨煤样自燃倾向性变化。研究表明:预氧化程度越高,煤样大孔含量越大,自燃危险性越高;在程序升温实验中检测出主要气体为CO、CH_(4)、C_(2)H_(4)、C_(2)H_(2);各类气体产生的初始温度随预氧化程度的升高而升高;预氧化煤样释放的CO、CH_(4)气体速率有超越原煤的趋势;通过热重发现煤样特征温度点(T_(1)、T_(2)、T_(3))和煤样活化能会随预氧化温度的升高而降低,得出预氧化煤样的自燃氧化能力强于原煤;煤样在低温氧化环境下,煤孔隙的结构变化和内部能量变化共同影响煤自燃倾向性。To investigate the problem related to spontaneous combustion of leftover coal in goaf,Donghuantuo gas coal was taken as the model material and pre-oxidizations at 80,160,and 230℃were carried out to study the difference in spontaneous combustion characteristics.In this paper,low-temperature nitrogen adsorption,temperature-programmed gas chromatography and thermogravi⁃metric(TG)experiments were used to study the pore changes of coal samples at different pre-oxidation temperatures,the changes of characteristic gases and activation energy in the early stage of spontaneous combustion oxidation,based on which the change of spontaneous combustion tendency of coal samples were explored.The results show that the higher the degree of pre-oxidization,the higher the content of macropores and the higher the risk of spontaneous combustion.The main gases are CO,CH_(4),C_(2)H_(4) and C_(2)H_(2) in the programmed temperature test.The initial production temperatures of all kinds of gases rise with the increase of pre-oxidization temperature.Among them,the rate of CO and CH_(4) gas released by pre-oxidized coal sample has a tendency to surpass that of raw coal.It is found that the characteristic temperature points(T_(1),T_(2),T_(3))of coal sample decrease with the increase of pre-oxidization temperature and the activation energy of coal sample decreases after low temperature oxidation.It is concluded that the spontaneous combustion oxidation capacity of preoxidized coal sample is stronger than that of raw coal.Additionally,the tendency of coal sponta⁃neous combustion of the coal sample is affected by the structural changes of coal voids and internal energy changes in low temperature oxidization environment.

关 键 词：二次氧化 自燃 自燃倾向性 孔隙结构 活化能 

分 类 号：TD752[矿业工程—矿井通风与安全]