采空区抽放负压对自燃影响规律研究

发布时间：2018-06-23 20:00

本文选题：抽放负压 + 自燃“三带”　；参考：《华北理工大学》2017年硕士论文

【摘要】：近年来,瓦斯抽放已成为防治采空区瓦斯事故灾患的重要手段,但抽放负压的存在影响了采空区气体流场,从而改变了采空区气体浓度环境,很大程度上影响到遗煤自燃问题,因此研究抽放条件下采空区自燃规律对煤矿安全开采极为重要。综合国内外应用及研究现状,在对煤炭自燃机理、采空区瓦斯抽放理论等现有研究的基础之上,通过部分实验室实验、现场束管监测试验以及大量的数值模拟计算,对吕家坨矿5877Y工作面埋管抽放不同负压条件作用下的采空区遗煤自燃规律进行了研究。基于流体力学、传热学和传质学等基本学科理论分析,建立了采空区遗煤自燃的多物理场耦合数学模型;通过工业分析、综合热分析等实验,测得煤体水分含量、煤体密度、放热强度等基础参数,并分析了煤样的放热情况,得出了放热量随温度的变化折线图,为后期数值模拟提供参考依据;通过对5877Y工作面布置束管监测回采期间采空区的氧浓度分布情况,并结合氧浓度指标划分出埋管抽放前采空区自燃“三带”的范围;通过建立采空区自燃发火数学模型,并利用COMSOL数值模拟软件解算,模拟得出不同抽放负压条件下的采空区流场、温度场和氧浓度场分布情况,划分出不同抽放负压条件下采空区自燃“三带”和高温危险区域,并对比束管监测实验数据与数值模拟分析结果,验证了数值模拟的准确性。最终利用数值模拟得出了不同抽放负压对采空区遗煤自燃的影响规律,准确预测了不同抽放负压条件下自燃“三带”以及高温危险区域的范围,对抽放条件下采空区遗煤自燃火灾防治工作的开展具有重要的现实指导意义。
[Abstract]:In recent years, gas drainage has become an important means to prevent and cure gas accidents in goaf, but the existence of drainage negative pressure has affected the gas flow field in goaf, which has changed the gas concentration environment in goaf and affected the spontaneous combustion of coal to a great extent. Therefore, it is very important to study the spontaneous combustion law of goaf in the condition of pumping. On the basis of existing research on coal spontaneous combustion mechanism, gas drainage theory in goaf and so on, through some laboratory experiments, field beam tube monitoring tests and a large number of numerical simulation calculations, this paper synthesizes the application and research status at home and abroad. The spontaneous combustion of coal left in goaf under different negative pressure conditions of buried pipe drainage in 5877Y face of Lujiatuo Coal Mine was studied. Based on the theoretical analysis of fluid mechanics, heat transfer and mass transfer, the multi-physical field coupling mathematical model of spontaneous combustion of coal in goaf is established, and the moisture content and density of coal body are measured by industrial analysis and comprehensive thermal analysis. The basic parameters such as exothermic intensity, and the exothermic situation of coal sample are analyzed, and the curve diagram of heat release with temperature is obtained, which provides a reference for the later numerical simulation. The distribution of oxygen concentration in goaf during mining period is monitored by arranging beam tube in 5877Y working face, and the range of "three zones" of spontaneous combustion in goaf before drainage of buried pipe is divided according to oxygen concentration index, and the mathematical model of spontaneous combustion in goaf is established. By using COMSOL numerical simulation software, the distribution of flow field, temperature field and oxygen concentration field in goaf under different pumping negative pressure conditions are obtained, and the "three zones" and high temperature dangerous areas of goaf spontaneous combustion under different suction negative pressure conditions are divided. The accuracy of the numerical simulation is verified by comparing the experimental data of beam tube monitoring with the results of numerical simulation. Finally, by using numerical simulation, the influence of different suction negative pressure on spontaneous combustion of coal in goaf is obtained, and the "three zones" of spontaneous combustion and the range of high temperature dangerous area under different suction negative pressure conditions are accurately predicted. It has important practical guiding significance for the fire prevention and control work of coal spontaneous combustion in goaf under the condition of pumping.
【学位授予单位】：华北理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD752.2

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