王洼二矿下分层综放开采煤自燃规律及防治技术

发布时间：2018-03-19 16:10

  本文选题：下分层　切入点：综放工作面　出处：《西安科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：煤炭自燃是我国煤矿重要灾害,不仅造成大量的资源损失,还严重威胁煤矿的安全生产。而煤矿开采方式是影响煤炭自燃的主要因素之一,其中在特厚煤层分层开采时,下分层重新揭露煤体受漏风影响会造成上分层遗煤再次氧化升温,使下分层开采时煤自燃危险性增大。当采用综放开采时,两巷顶煤放出率较低,采空区两道留有较大遗煤量,是煤自燃的多发地。王洼二矿5#特厚煤层03区段采用分层开采,上分层综采,下分层综放开采。下分层综放回采时,采空区与上分层采空区呈现相互连通,巷道顶板出现多处破碎带与上分层采空区贯通,致使预氧化的上分层浮煤发生再次氧化,煤自然发火概率增大。下分层采用综放工艺时,两道数米范围内顶煤放出率较低,留有大量遗煤,易发生煤自燃。因此,研究王洼二矿下分层综放开采时煤自燃特性及防治技术尤为重要。本文以王洼二矿下分层115032综放面为研究对象。首先,结合理论分析了下分层115032综放开采时煤自燃特点。其次,应用工业分析、表面结构分析、程序升温实验与大型煤自然发火实验对下分层115032综放面的混合煤样进行实验,得出煤样的挥发分、比表面积及微孔和中孔比例都较大,临界温度为50～60℃,干裂温度为110～120℃,C2H4出现煤温为70～90℃,C2H6出现温度为80～90℃,自然发火期为22天。再次,通过现场实测下分层115032综放面和215021综放面采空区浮煤厚度、氧气浓度和漏风强度的分布情况,结合实验所得煤自燃极限参数,得出下分层115032综放面采空区氧化升温带大于215021综放面采空区氧化升温带,且更接近工作面,窒息带深度相差不大。最后,根据实验和下分层115032综放面采空区煤自燃危险区域,应用注氮、注浆和高分子胶体的综合防灭火技术对巷道破碎顶板处与开切眼处煤自燃隐患进行治理,对回采、临时停采和回收期间煤自燃进行预防,实践证明综合防灭火技术对下分层115032综放面煤自燃防治起到了良好效果。文中的研究结果对相似本工作面的煤自燃防治提供了理论、实验和技术借鉴。
[Abstract]:Coal spontaneous combustion is an important disaster of coal mine in China, which not only causes a lot of loss of resources, but also seriously threatens the safety of coal production. Coal mining mode is one of the main factors affecting coal spontaneous combustion. The reexposure of coal body under the influence of air leakage in the lower stratification will result in the reoxidation and heating of the upper stratified coal, which will increase the danger of spontaneous combustion of coal in the next stratified mining. When fully mechanized caving mining is adopted, the caving rate of the top coal in the two roadways is lower, and the coal left in the two goaf is larger than that in the goaf. Wwangwa No.2 Coal Mine adopts stratified mining, upper stratified fully mechanized mining, lower stratified fully mechanized caving mining. When fully mechanized caving mining in lower stratification, goaf and upper stratified goaf are connected with each other. There are many broken zones in the roof of the roadway and the goaf of the upper layer, which leads to the re-oxidation of the upper stratified floating coal, which increases the spontaneous combustion probability of the coal. When the fully mechanized caving process is adopted in the lower layer, the caving rate of the top coal in the range of two meters is low. A large amount of residual coal is left, which is prone to spontaneous combustion of coal. Therefore, it is particularly important to study the characteristics of coal spontaneous combustion and the prevention and control technology in fully mechanized coal caving mining. This paper takes 115032 fully mechanized top-coal caving face under Wangwa No. 2 Mine as the research object. Combined with the theory, the characteristics of coal spontaneous combustion in 115032 fully mechanized caving mining are analyzed. Secondly, the mixed coal samples of 115032 fully mechanized caving face are tested by industrial analysis, surface structure analysis, temperature-programmed test and large coal spontaneous combustion test. The results show that the volatile matter, specific surface area and the ratio of micropore to mesopore of coal sample are large, the critical temperature is 50 ~ 60 鈩，

本文编号：1635008