临涣矿区东南缘瓦斯赋存构造控制特征及防治技术研究

发布时间：2018-11-16 07:45

【摘要】：针对淮北煤田临涣矿区东南缘矿井瓦斯赋存和突出灾害具有明显的构造控制特征这一特点，本文运用地球化学、构造地质学、岩石矿物学、物理化学、渗流力学、岩石力学等多学科交叉的研究方法，采用理论分析、数值模拟、实验室测定分析与现场工程实践等手段，以该区域两大典型矿井——许疃和任楼煤矿做为研究对象，，对构造控制下的矿井瓦斯赋存状态与赋存规律进行了研究，提出相应的分区分级安全开采技术体系。论文的研究内容对建立单一煤层条件下或煤层群赋存条件下的区域性瓦斯综合治理技术体系有着重要的理论指导意义。论文针对许疃煤矿33采区南北翼瓦斯差异性赋存特征以及采区南翼有大面积厚层古近系红层沉积的特点，通过地面钻井采集岩样，对比分析了红层与常见煤系地层岩石（泥岩、砂岩、粉砂岩）在矿物成分、孔隙结构、渗透性以及煤层瓦斯封盖能力上的差异。结合33采区煤样的多元物性参数测试结果，发现红层沉积对煤的物性参数没有显著影响，造成采区南北两翼瓦斯差异性赋存的原因主要在于煤层上覆巨厚红层的影响。红层的孔隙结构以小孔和中孔为主，与砂岩、泥岩和粉砂岩相比具有高孔隙率、高渗透性的特点，对煤层瓦斯的封盖能力较差。现场瓦斯含量和瓦斯成分测定结果也表明红层覆盖区32煤层瓦斯含量小、煤层瓦斯赋存呈现瓦斯风化带特征，说明在红层沉积的区域煤系地层透气性好，其下伏煤层瓦斯逸散作用强烈，煤层的煤与瓦斯突出危险性也随之减弱。任楼煤矿靠近徐宿弧形推覆构造南段前缘，井田内石炭-二叠系煤层自沉积以来经受过两期或者两期以上大型地质构造运动的改造作用，构造极为发育。针对这一特点，本文对任楼煤矿的构造，特别是断层的分布特点进行了梳理，对矿井的地应力进行了测量，对采煤工作面过小断层时的瓦斯涌出特征开展了系统分析。研究发现任楼煤矿以水平应力为主导，最大水平主应力与垂直应力之比为2.46～2.72，且均为压应力，这一地应力分布特点为构造煤的形成提供了力学条件，同时局部的构造残余应力也容易成为诱导突出发生的重要因素。此外，任楼矿小型断层两侧的瓦斯异常涌出具有一定的规律性，最大瓦斯涌出段至断层点的距离和瓦斯异常涌出范围均与断层落差呈良好线性关系；断层附近瓦斯涌出量峰值出现的位置以及瓦斯异常涌出范围分别约为断层落差的35倍与60倍。最后，根据许疃煤矿和任楼煤矿瓦斯赋存的构造控制特点，分别建立了适用于许疃煤矿32煤层的单一煤层分区分级瓦斯综合治理技术体系和适用于任楼煤矿7、8煤层的保护层开采及卸压瓦斯强化抽采治理技术体系。
[Abstract]:In view of the obvious structural control characteristics of gas occurrence and outburst disaster in the southeast edge of Linhuan mining area in Huaibei coalfield, this paper applies geochemistry, tectonics, petromineralogy, physicochemistry, seepage mechanics, etc. By means of theoretical analysis, numerical simulation, laboratory analysis and field engineering practice, the two typical mines in this area, Xutuan and Renlou Coal Mine, are taken as the research objects. This paper studies the occurrence state and occurrence law of mine gas under structural control, and puts forward the corresponding technical system of classified and safe mining. The research content of this paper has important theoretical guiding significance for the establishment of regional comprehensive gas control technology system under the condition of single coal seam or the condition of coal seam group occurrence. In view of the characteristics of gas diversity in the north and south wing of Xutuan coal mine area 33 and the characteristics of large area thick Paleogene red bed deposits in the south wing of the mining area, rock samples collected from surface drilling are compared and analyzed between red bed and common coal measure strata (mudstone). The differences in mineral composition, pore structure, permeability and sealing ability of coal seam gas. Combined with the test results of multivariate physical parameters of coal samples in No. 33 mining area, it is found that red bed deposition has no significant effect on the physical parameters of coal, and the main reason for the difference in gas occurrence between the north and south wings of the mining area lies in the influence of the overlying thick red bed on the coal seam. Compared with sandstone, mudstone and siltstone, the pore structure of red bed is characterized by high porosity and high permeability, and the sealing ability to coal seam gas is poor. The results of gas content and gas composition measurement also show that the gas content of 32 coal seam in the red bed overburden area is small, and the gas weathering zone of coal seam gas occurrence is characteristic, which indicates that the gas permeability of coal measure strata in the red bed sedimentary area is good. The risk of coal and gas outburst is also weakened because of the strong gas emission in the underlying coal seam. Renlou coal mine is close to the front edge of Xushu arc nappe structure, and the coal seam of Carboniferous-Permian system in the mine field has undergone two or more periods of reformation of large-scale geological tectonic movement since sedimentation, and the structure is extremely developed. Aiming at this characteristic, this paper combs the structure of Renlou coal mine, especially the distribution characteristic of fault, measures the ground stress of coal mine, and makes a systematic analysis of the gas emission characteristics when the coal face passes through the small fault. It is found that the horizontal stress is dominant in Renlou Coal Mine, and the ratio of maximum horizontal principal stress to vertical stress is 2.46 ~ 2.72, both of which are compressive stress, which provides a mechanical condition for the formation of tectonic coal. At the same time, local tectonic residual stress is also easy to become an important factor of induced outburst. In addition, the abnormal gas emission on both sides of the small fault in Renlou Mine has certain regularity. The distance from the maximum gas emission section to the fault point and the range of abnormal gas emission are all in good linear relationship with the fault drop. The location of peak value of gas emission near fault and the range of abnormal gas emission are about 35 times and 60 times of fault drop respectively. Finally, according to the structural control characteristics of gas occurrence in Xutuan Coal Mine and Renlou Coal Mine, The technical system of comprehensive gas control for single coal seam zone classification in Xutuan Coal Mine No. 32 seam and the technology system for mining protective layer and enhanced drainage of unpressurized gas in No. 7 No. 8 seam of Renlou Coal Mine are established respectively.
【学位授予单位】：中国矿业大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TD712.2

【参考文献】