复杂因素影响下矿井CO气体来源辨识及涌出规律研究

In order to make clear the source and emission law of carbon monoxide and the critical index for forecasting coal spontaneous combustion on the basis of carbon monoxide in coalmines, the technological means of laboratory experiments, theoretical analysis, numerical simulation and field combined tests would be adopted in the item. Meanwhile, coal mining theory, coal mine fire prevention theory, coal geology theory, gas geology theory, coal chemistry theory and quantum chemistry would be across used. The viewpoint that the source of carbon monoxide was comprised of the primal and secondary carbon monoxide is put forward on the basis of analyzing the source and origin of carbon monoxide. And then the classification identification method of carbon monoxide is set up. The mathematical model of carbon monoxide migration in the mining fissure field is established according to the prototype of the test working face on the basis of the physical analog simulation test and FLAC numerical simulation. Then the characteristics of migration and diffusion of carbon monoxide is analyzed. Finally, the emission and accumulation characteristics of carbon monoxide in the coalface which are influenced by complex factors are researched. The volume fraction of the primary and secondary carbon monoxide of the total carbon monoxide in the coalface is analyzed and calculated through the comprehensive analysis by the fuzzy mathematics theory. The forecasting system as carbon monoxide major is built. It could provide the scientific basis of forecasting coal spontaneous combustion accurately. Through the research, the item has the important theoretical and practical significance.

项目通过实验室实验、理论分析、数值模拟与现场综合试验等相结合的研究方法，综合运用煤矿开采学、矿井火灾学、煤田地质学、瓦斯地质学、煤化学、色谱分析技术等多学科交叉方法和分析手段，分析CO气体来源及成因类型，提出CO气体成因类型由原生CO气体和次生CO气体构成,建立一套行之有效的CO气体分类辨识方法。以试验工作面为原型，基于物理相似模拟试验和FLAC数值模拟，建立采动裂隙场中CO运移的数学模型，研究CO气体在采动裂隙场中的运移扩散特征。研究复杂因素影响下采煤工作面CO涌出与积聚特征，综合运用模糊数学理论对数据进行处理和分析，分析、计算采煤工作面CO气体构成中原生CO气体和次生CO气体的体积分数，确定并构建基于现场实际条件的CO预测煤自燃临界值及预测模型。

论文采用实验室实验、现场综合观测、理论分析与数值模拟相结合的方法，系统开展了综放采场CO涌出特征和采空区煤自燃危险区域判定等方面的研究，这对于煤矿内因火灾防治具有重要的理论意义和实用价值。综放采场煤自燃的基础特性与矿压显现方面，通过综合热分析实验揭示了煤自燃进程失水失重、氧化增重和燃烧失重等反应现象的本质和特征温度的变化规律，发现了煤自燃进程不同增失重阶段对应不同临氧体积分数的客观现象。提出了将煤自燃析出的气态产物分为解吸气体、氧化气体和热解气体的分类方法，计算获得了氧化气体和热解气体生成的活化能，指出了CH4、C2H6、C3H8、C2H4和C3H6等气体的生成是多元反应综合作用的结果。通过矿压现场观测与UDEC数值模拟，分析获得了试验采场的断裂带基本顶、基本顶初次及周期来压步距，指出了基本顶失稳形式为滑落失稳，垮落形式为台阶岩梁结构的整体切落。根据采场底板支承压力的变化规律划分了“矿压水平三带”，为后续划分采空区煤自燃三带提供了理论支撑。.综放采场CO涌出与来源辨识方面，在系统分析矿井CO气体成因类型与产生机理的基础上提出了原生和次生CO气体的分类方法。通过多参量的相关性分析，辨识出了试验采场CO气体的主要来源。结合采场矿压显现特征揭示了回风隅角CO气体周期性增大涌出是周期性滑落失稳形成的冲击力挤压模拟墙前方采空区CO气体造成的。采空区煤自燃危险区域判定方面，获得了采空区O2与CO体积分数在走向方向和倾向方向上的变化规律，阐述了CO体积分数法划分采空区煤自燃三带的具体方法。利用氧体积分数法和漏风流速模拟法分析证明了CO体积分数法划分采空区煤自燃三带是可行和切合实际的。阐述了采空区煤自燃三带与矿压水平三带的对应关系，并取CO体积分数法、氧体积分数法和漏风流速法划分的氧化自燃带的交集作为采空区的煤自燃危险区域，计算获得了预防采空区煤自燃的安全回采速度。