煤自燃高温环境中多元可燃性气体链-热爆炸动力学研究

The interaction mechanism of coal spontaneous combustion and mine gas explosion has always been a focused but difficult scientific problem in mining industry. As the disaster of coal spontaneous combustion has main features of high temperature and multiple combustible gases decomposed from the pyrolysis and oxidation of coal. In this research, the gases of CH4/CO/H2/C2H4/C2H6 would be took as medium, the self-made visualization sealed spherical gas explosion equipment would be employed as experimental apparatus, the transient spectroscopy measurement system, the particle image velocimetry system (PIV), and the planar laser induced fluorescence system (PLIF), combined with the software of FLACS, GAUSSIAN and CHEMKIN would be conducted as main methods. The influences of different initial temperature, various gases composition with multi-ratios and mole fractions on the explosion characteristics would be explored by analyzing the explosion sensitivity of multiple combustible gases at high temperature caused by spontaneous combustion, the emission spectrum of the intermediate products, the explosive fields information and the chain-thermal process of explosion. The chain - heat internal relevance during explosion will be studied as well. Thus we can get the explosion dynamic parameters of chain-thermal reaction at high temperature caused by coal spontaneous combustion, reveal the chain-thermal regime of the explosion reaction, and provide theoretical basis to preventing the gas explosion caused by coal spontaneous combustion.

煤自燃与瓦斯爆炸耦合致灾机理一直是煤矿安全研究领域的热点和难点。针对矿井煤自燃火灾环境具有温度高、煤氧化和热解释放出的可燃可爆性气体构成复杂等特征，将CH4/CO/H2/C2H4/C2H6等多元可燃性气体作为研究对象，以自主研制的可视化气体爆炸实验系统为实验平台，采用瞬态光谱测量、PIV、PLIF光学测试等先进仪器，结合FLACS、GAUSSIAN和CHEMKIN数值模拟软件，在不同温度、可燃性气体种类、混合气体浓度及组分配比等条件下，研究煤自燃高温环境中多元可燃性气体爆炸引发敏感性、中间产物光谱特征与辐射强度、爆炸过程多场信息特征、以及爆炸链-热反应微观进程等，建立爆炸反应过程的链-热内在关联，掌握煤自燃高温环境中多元可燃性气体链-热爆炸动力学特性参数，揭示其爆炸链-热反应的诱导-促进机制，为预防与控制煤自燃引起瓦斯爆炸提供理论依据。

煤层自燃与瓦斯爆炸都是威胁煤矿安全生产的五大灾害之一。随着煤矿开采强度的加大、深度的延深，煤矿瓦斯涌出量越来越大、地温也越来越高。煤自燃引起的瓦斯爆炸是煤矿非常典型且常有发生的灾害事故，造成了巨大的经济损失并严重威胁着矿工生命安全。本项目紧密围绕煤矿安全领域中的煤自燃与瓦斯爆炸耦合致灾机理这一研究热点和难点，针对矿井煤自燃火灾环境温度高、煤氧化和热解释放出的可燃可爆性气体构成复杂等特征，选取煤自燃环境中的五种典型可燃性气体CH4/CO/H2/C2H4/C2H6，采用自主研制的可视化气体爆炸实验系统，结合瞬态光谱测量、PIV等先进光学测试手段以及FLACS、GAUSSIAN、CHEMKIN数值模拟与计算，在不同温度、可燃性气体种类、混合气体浓度及组分配比等工况条件下，获得了多元可燃性气体爆炸极限特征、中间产物光谱特征、爆炸过程多场信息特征、以及爆炸链-热反应微观进程等，进行了多元可燃性气体爆炸反应微观热力学和动力学分析；掌握了多元可燃气体爆炸点火特性与效应特性关键参数的影响规律、爆炸压力与火焰传播发展行为变化规律、爆炸过程关键自由基产生时序与浓度变化规律；构建了多元可燃气体爆炸压力与中间产物的时间耦合模型、基于火焰扩散边界层理论预测可燃气最小点火能的物理模型、以及点火能与自由基对可燃气体爆炸的热力学作用模型；通过以上研究，揭示了多元可燃性气体爆炸引发敏感性与微观反应机理，建立了煤自燃高温环境中多元可燃性气体爆炸过程及特性表征参数之间宏观-微观的内在关联和链-热的内在关联。本项目研究成果为预防与控制煤自燃引起瓦斯爆炸提供了理论依据，可有效指导矿井火区安全治理，对保障煤炭资源开发的防火防爆安全具有重要的科学意义和现实意义，社会经济效益显著，推广应用前景广阔。