文档介绍：防灭火均压系统非稳定性研究及其应用
摘要
随着综采放顶煤技术的推广和应用,矿井生产逐步向高产高效集约化发展。但由于该方法冒落高度大、采空区遗煤多、漏风严重,使得煤层自然发火几率增高,矿井自燃火灾事故增多。均压防灭火技术就是一种常用的防治煤炭自然发火的措施,与其它防灭火技术相比,其具有工程量少、投资少、见效快等优点。为此,研究均压防灭火技术对防治煤矿自燃火灾有重大的理论和现实意义。
本文首先在前人对均压防灭火技术研究的基础上,通过分析自燃与漏风的关系,论述了均压防灭火的原理。并以局部通风机—调节风窗均压系统为例,对均压系统非稳定性影响因素进行了分析,得出采空区内外压差随时间变化的函数,并总结出了均压系统的调节方法。
其次,在分析采空区内冒落煤岩体的多孔介质特征后,采用渗流力学理论建立采空区内CO渗流的数学模型,并应用FLUENT软件对6-201综放工作面采空区内CO渗流流场进行数值模拟,得出渗流区域内CO浓度分布和压力分布。
最后,以内蒙古特弘集团来叶沟煤矿为例,根据6-201综放工作面启封的要求,建立了局部通风机—调节风窗均压通风系统。并通过适时地调节回风巷调节风窗,减少了非稳定性影响因素的扰动,降低了工作面CO涌出量,抑制了采空内火区复燃的势头,保证了工作面的安全生产,最终成功启封了来叶沟煤矿6-201综放工作面的火区。该火区的成功扑灭,为类似矿区扑灭采空区火灾提供了成熟的技术和经验。
关键词:煤炭自燃;数值模拟;均压系统;防灭火
Abstract
With the promotion and application of coal caving technology, the trend of coal production tends to be high efficiency and intensive. However, as the method tend to be high caving, more coals left, and serious air leakage, the risk of bustion increased, as well as the fire accident. The technology of even pressure is monly used measure of bustion, compared with other fire extinguishing technology, which has advantages of less quantities, lower investment, etc. Studying the technology of even pressure for fire extinguishing has great theoretical and realistic significance to control the spontaneous fires.
First, this paper analyzes the relationship between bustion and air leakage; discusses the principles of pressure balance for fire extinguishing on the base of the current research about the fire prevention system. And then makes an assay of the factors that impact the even pressure system, for an example of local fan - adjust pressure. Constructs a function of inside and outside gob pressure difference as the time-varying. The even pressure system adjustment method is summarized.
Second, based on the analysis of porous-medium characteristics of rocks in the coal gob caving, the paper establishes a model of CO flows, by using the theory of permeation fluid mechanics. Then we use the software of FLUENT to make numerical simulation fo