露天矿采空区空洞火区治理方法研究

发布时间：2019-05-24 18:03

【摘要】：露天矿采空区空洞火区是露天矿生产过程中面临的最大威胁,它不仅烧毁和冻结大量煤炭资源,易造成大型生产设备陷落,影响露天矿的经济效益,而且对生态环境也造成了巨大的破坏,因此必须对露天矿采空区空洞火区进行研究和治理。采空区空洞火区具有三维立体特征,内部空间巨大,传统的注水、注浆等防灭火技术难以对空洞火区进行全方位治理。泡沫具有优良的堆积性能,对露天矿空洞火区具有很强的适用性,但是现有露天矿泡沫制备装置产泡能力弱,难以满足现场需求。本文采用理论分析、实验研究和现场结合的方法,进行了以大流量灌注泡沫为主的露天矿采空区空洞火区治理方法研究,取得的主要成果和结论如下:设计了新型大流量泡沫制备装置。从网孔成泡机理和泡沫的力学性质以及衰变机理分析了网式发泡的成因及影响因素。装置主要由螺旋喷头组、复合凹面网和高压离心风机构成,螺旋喷头组可以将泡沫液很好的雾化并均匀喷洒到复合凹面网上,复合凹面网则能够对泡沫液进行吸附并形成液膜,风机则为泡沫制备提供气源和动力。测试了大流量泡沫制备装置的产泡性能。利用自主构建的装置产泡性能实验系统,采用控制变量、分组多次实验的方式,探究了气体流量和液体流量对装置产泡性能的影响,实验研究表明:在1000~3000m3/h供风量范围内,装置产泡量随着供风量的增加出现先增加后减小的现象,装置发泡倍数的变化趋势和产泡量的变化趋势相似,最大产泡量出现在2100~2300m3/h供风量时,说明对于特定尺寸的泡沫制备装置,最佳产泡效果时的风速是一定的。在6~16m3/h供液量范围内,装置产泡量随着供液量的增加呈逐渐增加的趋势,而装置发泡倍数随着供液量的增加呈先增加后减小趋势。供液量较小时,泡沫呈不连续碎片状,此时装置风量利用率低,供液量过大时,泡沫内出现大量过剩的泡沫液,泡沫液并没有完全发泡,发泡倍数降低,综合考虑,该装置的最佳供液量为10~12m3/h。研究了泡沫的堆积特性。利用自主构建的可视化采空区空洞模型,研究了泡沫在采空区空洞内的堆积规律,研究表明,泡沫在受限空间内具有优良的堆积能力,堆积过程可分为三个阶段,第一阶段,泡沫沿着空洞模型底板扩散流动,该阶段中后期泡沫呈匀速流动状态;第二阶段,泡沫整体堆积高度增加,左侧壁面处泡沫高度增加速度快,最先到达模型顶板;第三阶段,泡沫从模型两边开始,逐渐将整个空洞模型空间充填满。开展了露天矿采空区空洞火区灭火工程实践。针对中煤平朔集团安家岭矿采空区空洞火区成因及特点,确定了“前期火区灭火降温、后期火区空洞全方位充填”的火区治理方案,提出了以大流量灌注泡沫为主体,辅助以注浆和注高水材料的综合灭火方法,首先采用注浆措施处理火区内部低位火源,然后向火区内部灌注泡沫,待完全熄灭火区火源后,采用超高水材料将火区空洞完全充填,防止火区复燃,取得了很好的灭火效果。
[Abstract]:The hollow fire area in the mined-out area of the open-pit mine is the greatest threat to the production of the open-pit mine. It not only burns and freezes a large amount of coal resources, but also causes the large-scale production equipment to fall, has an impact on the economic benefit of the open-pit mine, and also causes great damage to the ecological environment. Therefore, it is necessary to study and control the hollow fire area in the goaf of the open-pit mine. The hollow fire area of the goaf has three-dimensional and three-dimensional characteristics, the inner space is huge, and the traditional fire-fighting technology such as water injection, grouting and the like is difficult to carry out all-round treatment on the hollow fire area. The foam has excellent stacking performance, and has strong applicability to the open pit fire area, but the foam preparation device of the existing open-pit mine has weak foaming capacity and is difficult to meet the on-site demand. In this paper, by means of theoretical analysis, experimental research and on-site combination, the method of the treatment of the hollow fire area in the goaf of the open-pit mine with large flow perfusion foam is carried out. The main results and conclusions are as follows: a new type of large-flow foam preparation device is designed. The mechanism of cell formation and the mechanical properties of the foam and the mechanism of decay are used to analyze the causes and influencing factors of the net-type foaming. The device is mainly composed of a spiral spray head group, a composite concave net and a high-pressure centrifugal fan, And the air source and the power are provided for the foam preparation. And the foaming property of the large-flow foam preparation device is tested. The effect of gas flow and liquid flow on the bubble performance of the device was investigated by means of the self-constructed experimental system of the bubble performance of the device. The experimental results show that in the range of 1000-3000 m3/ h for air flow, The foaming quantity of the device is reduced by the increase of the air supply volume, the variation trend of the foaming multiple of the device and the change trend of the bubble generation amount are similar, and when the maximum bubble generation amount occurs between 2100 and 2300 m3/ h for air flow, the foam preparation device for the specific size is described. The wind speed at the time of the optimal bubble generation is certain. In the range of 6 ~ 16m3/ h, the foam volume of the device gradually increases with the increase of the liquid supply, and the foaming multiple of the device decreases with the increase of the liquid supply. When the liquid supply amount is small, the foam is in the form of discontinuous chips. At this time, the air volume of the device is low, and when the amount of liquid supply is too large, a large amount of excess foam liquid is present in the foam, the foam liquid is not completely foamed, the foaming multiple is reduced, and the optimal liquid supply amount of the device is 10 to 12 m3/ h. The pile-up properties of the foam were studied. By using the self-constructed visualization goaf cavity model, the accumulation law of the foam in the empty space of the goaf is studied. The research shows that the foam has excellent stacking capacity in the confined space, and the stacking process can be divided into three stages, in that second stage, the foam height of the foam is increase, the foam height at the left side wall surface is high, the first reach the model top plate, and the third stage, the foam starts from both sides of the model, The entire cavity model space is gradually filled with space. The practice of fire-fighting in the hollow fire area of the goaf in the open-pit mine is carried out. In view of the origin and characteristics of the hollow-fire zone in the Goaf of Anjialing Mine of the medium-coal-Pingshuo Group, the fire zone control scheme of the "Fire-fighting and cooling in the early-stage fire area and all-round filling in the fire area in the later stage" is determined, and a comprehensive fire-extinguishing method with large flow perfusion foam as the main body and auxiliary for grouting and high-water-filling materials is put forward, Firstly, a grouting measure is adopted to deal with the low-order fire source in the fire area, and then a foam is poured into the fire area, and after the fire area fire source is completely extinguished, the fire area cavity is completely filled with the ultra-high water material, so that the fire area is prevented from re-burning, and a good fire-extinguishing effect is achieved.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD753

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