【作者】 张春；

【导师】 题正义；

【作者基本信息】 辽宁工程技术大学 ， 安全技术及工程， 2013， 博士

【摘要】 随着综放开采方法的广泛应用,综放采场煤炭自燃已经成为矿井的主要灾害之一,严重影响安全高效矿井的建设。数值模拟分析是对其进行研究的主要方法之一因此,本文在对综放采场煤炭自燃特性分析的基础上,开展综放采场煤炭自燃三维数值模型构建的研究,并利用模型对综放采场煤炭自燃规律及防治措施进行研究。基于遗煤厚度与冒落煤岩空隙率对综放采空区煤炭自燃影响的重要性,采用理论分析方法对遗煤厚度、冒落煤岩空隙率进行了研究,得到了依据顶板压力与碎胀系数确定遗煤厚度及冒落煤岩空隙率的方法；并对受压遗煤进行了实验研究,得到了遗煤厚度对煤炭自燃的影响规律。由于综放采场极限平衡区顶煤也易发生自燃,应用回归分析方法、损伤力学理论及实验方法,对综放采场极限平衡区宽度及顶煤渗透率进行了研究,得到了极限平衡区宽度的确定方法及计算顶煤渗透率的经验公式。通过对综放采场煤炭自燃的渗流场、浓度场、温度场的特点分析,构建了综放采场煤炭自燃三维数值模型,并对具体条件下极限平衡区及采空区的煤炭自燃进行了模拟,通过对现场观测数据与数值模拟结果的对比分析,证明了所构建综放采场煤炭自燃三维模型的正确性及模拟结果的可靠性。利用所建数值模型对综放极限平衡区及采空区煤炭自燃规律进行了分析,得到了工作面供风量与顶煤升温时间及高温点位置、与采空区氧化带高度及宽度、与采空区高温点位置及遗煤升温时间的关系；耗氧速度与自然发火期的关系；综放采空区“三带”划分及温度场分布的特点。依据构建数值模型对九道岭矿E1S6综放面采空区煤炭自燃特点进行了分析,提出了具有针对性的注氮防治措施,并对其有效性进行了数值模拟分析。分析结果表明,该措施能够发挥采场煤炭自燃控制作用。最后,将防治措施在九道岭矿进行了实际应用,并取得了较好的防治效果,证明了所构建综放采场煤炭自燃数值模型的实用性。更多还原

【Abstract】 With the widespread application of fully mechanized caving mining, the coal spontaneous combustion of fully mechanized caving mining in stope has become one of the serious mine disasters, and it has seriously affected the construction of mine that is safe and efficient. The numerical simulation analysis is one of the main research methods for it. So the construction of3d numerical model of coal spontaneous combustion of stope for fully mechanized caving mining is studied in this thesis based on the analysis of coal spontaneous combustion characteristics of fully mechanized caving mining in stope. And the numerical model is applied to study the rules and the control methods of coal spontaneous combustion of fully mechanized caving mining in stope.Based on the importance of thickness of residual coal and voidage of fractured rock to coal spontaneous combustion of goaf, the theoretical analysis method is applied to study thickness of residual coal and voidage of fractured rock. The methods for determining the thickness and the voidage based on the roof pressure and the expansion coefficient of fractured rock are obtained. The experiment of coal spontaneous combustion under pressure is done, and the influencing rule of thickness of residual coal on spontaneous combustion is obtained.Because the top-coal spontaneous combustion of limit equilibrium zone is possible in stope of fully mechanized caving mining, the method of regression analysis, the theory of damage mechanics and experimentation are applied to study width of limit equilibrium zone and permeability of top-coal of fully mechanized caving mining in stope. The method for determining width of limit equilibrium zone and the empirical formula for calculating permeability of top-coal are obtained.According to the analysis on the characteristics of seepage field, concentration field and temperature field of coal spontaneous combustion of fully mechanized caving mining in stope, the3d numerical model of coal spontaneous combustion of stope for fully mechanized caving mining is constructed, and the coal spontaneous combustion of limit equilibrium zone and goaf are simulated under given conditions. Based on the contrast analysis on the actual observation data and the simulation results, the correctness of the3d numerical model and the reliability of simulation results are proved.The3d numerical model is used to analyze the rules of coal spontaneous combustion of limit equilibrium zone and goaf. The relations of air-volume of working face and the heat-up time of top-coal, and the position of high temperature of top-coal, and height of oxidation zone, and width of oxidation zone, and the position of high temperature of goaf, and the heat-up time of residual coal are obtained. At the same time, the relation of oxygen consumption velocity and spontaneous combustion period, the characteristics of three zones division and temperature field distribution of goaf of fully mechanized caving mining are also achieved.The characteristics of coal spontaneous combustion of goaf of E1S6working face in Jiu Daoling mine is analyzed through the3d numerical model, and the nitrogen injection scheme is selected to prevent coal spontaneous combustion based on the characteristics. The efficiency of nitrogen injection is analyzed through the method of numerical simulation. The results of analysis show that the prevention measure can control coal spontaneous combustion of stope. At last, the prevention measure is used in Jiu Daoling mine, and the prevention measure has good control effect to coal spontaneous combustion of goaf. The practicality of the3d numerical model of coal spontaneous combustion of stope for fully mechanized caving mining is proved.更多还原