煤自燃过程中极限参数的研究

Research on Key Parameters in the Process of Coal Self-Ignition

煤自燃过程是煤氧化产热和环境散热之间热平衡关系的变化过程 .通过对煤自燃过程的热平衡关系进行分析 ,导出了煤体氧化蓄热升温的必要条件的数学表达式 .在此基础上 ,研究得出了上限漏风强度、上限煤体粒度、下限氧含量和下限煤体厚度 4个煤自燃过程的重要极限参数 .研究结果表明 ,任何一种煤在氧化蓄热过程中 ,只有同时满足煤体的漏风强度小于该煤体的下限漏风强度 ,煤体粒度小于其上限煤体粒度 ,煤体中的氧含量大于其下限氧含量 ,以及煤体厚度大于其上限煤体厚度 ,才有可能引起自燃 .这一研究结果为进一步完善煤自燃理论以及研究新型自燃防治技术提供了必要的理论基础 .

According to analysis of the process of coal self-ignition, it is put forward that the process of spontaneous combustion is a variety process of thermo-balance relationship between heat producing from oxidizing coal and heat radiating to surroundings. The prerequisite for temperature rising of coal is presented by analyzing the thermal balance relationship in the process of coal self-ignition. Some key limit parameters of spontaneous combustion, include superior intensity limit of air leakage, superior particle size limit of coal, inferion limit of oxygen concentration and inferior thickness limit of coal, are obtained. The study shows that the spontaneous combustion will be possible for every kind of coal only when the following conditions are simultaneously met: the intensity of air leakage in coal is smaller than the upper limit of intensity of air leakage, the granularity of coal is smaller than its upper limit granularity, the concentration of oxygen in coal is larger than its lower limit concentration of oxygen and the thickness of coal is larger than its lower limit of thickness. The study provides essential theoretical basis for advanced improvement of spontaneous combustion theory and study of the prevention and cure of spontaneous combustion.