高赋水煤岩层下向钻孔瓦斯抽采技术研究

发布时间：2018-04-03 00:17

本文选题：赋水状态　切入点：下向钻孔　出处：《安徽理工大学》2014年硕士论文

【摘要】：随着开采深度的增加,地应力、瓦斯含量与压力不断增高,矿井瓦斯涌出量和瓦斯灾害的威胁急剧增加,高瓦斯和煤与瓦斯突出矿井逐渐增多,如何采取有效措施实现安全高效开采成为摆在采矿工作者面前的重要任务。特定条件下,煤层采前预抽也是一种有效的区域性预防突出的技术措施,它对煤层赋存条件的要求较低,施工容易,成本较低。随着煤矿范围的扩大、开采深度的增加,瓦斯灾害日益加剧,由于受矿井采掘布置的影响,在矿井许多区域有必要采用下向钻孔进行瓦斯抽采,且顾北矿煤层顶底板赋水丰富,造成下向钻孔施工困难,瓦斯抽采效果不好,因此,研究矿井高赋水条件下向长钻孔的成孔、护孔工艺、排水工艺、封孔工艺、抽采考察工艺等关键技术,通过现场试验拟解决下向长钻孔抽采瓦斯的技术难点,实现下向长钻孔抽采瓦斯并获得很好的瓦斯抽采效果。本次课题研究是在充分搜集顾北煤矿大量文献资料基础上,通过大量现场试验与实验室实验,掌握了顾北煤矿4层瓦斯基础参数,得出顾北煤矿4层钻孔瓦斯流量衰减系数在0.09248d-1～0.1009d-1范围内波动,平均钻孔瓦斯流量衰减系数为0.09742d-1,透气性系数为0.090358654m2/MPa2·d。依据瓦斯压力降低法原理,通过长期观测不同距离测压孔瓦斯压力变化和经过科学合理的测算可以得出顾北煤矿4层在连续抽采一个月时抽采半径可以达到3m。所研制的下向钻孔施工成套技术(下向孔成孔工艺、套管护孔、机械动压注浆法封孔、喷注浆防水及瓦斯抽采排水技术装置),解决了煤层集中应力对下向钻孔垮孔、抽采封孔漏气等问题,满足了试验区域下向长孔层间含水条件下瓦斯抽采需要,提高了下向钻孔抽采效果。
[Abstract]:With the increase of mining depth, the in-situ stress, gas content and pressure are increasing constantly, the mine gas emission and the threat of gas disaster are increasing sharply, and the high gas and coal and gas outburst mines are increasing gradually.How to take effective measures to realize safe and efficient mining has become an important task for miners.Pre-extraction before mining is also an effective regional technical measure to prevent outburst under specific conditions. It has lower requirements for coal seam occurrence conditions easy construction and low cost.With the expansion of coal mine scope and the increase of mining depth, the gas disaster is becoming more and more serious. Because of the influence of mining arrangement, it is necessary to use downward drilling hole for gas extraction in many areas of the mine, and the top and bottom slab of the coal seam in Gubei Mine is rich in water.As a result of the difficulty in the construction of downward drilling and the poor effect of gas extraction, this paper studies the key techniques such as hole formation, hole protection, drainage, sealing, extraction and investigation under the condition of high incidence of water in the mine, and so on.Through the field test, the technical difficulties of gas extraction from the downward long borehole are solved, the gas extraction from the downward long borehole is realized and the good gas drainage effect is obtained.On the basis of collecting a large number of documents in Gubei Coal Mine, the paper grasps the basic parameters of gas in four layers of Gubei Coal Mine through a lot of field tests and laboratory experiments.It is concluded that the attenuation coefficient of gas flow in four layers of Gubei Coal Mine fluctuates in the range of 0.09248d-1~0.1009d-1, the average attenuation coefficient of gas flow in borehole is 0.09742 d ~ (-1), and the permeability coefficient is 0.090358654m2/MPa2 d.According to the principle of gas pressure reduction method, through long-term observation of gas pressure changes in different distance pressure measuring holes and scientific and reasonable calculation, it is concluded that the drawing radius of the four layers of Gubei Coal Mine can reach 3 m after one month of continuous extraction.The whole set of down-hole construction technology (down-hole forming technology, casing protecting hole, mechanical dynamic grouting sealing, grouting waterproof and gas drainage and drainage) have been developed to solve the problem that the concentrated stress of coal seam can bring down hole to the down-hole.The problems such as gas leakage and so on are satisfied with the need of gas extraction under the condition of water cut in the bottom long hole layer in the test area, and the effect of the downward hole drainage is improved.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TD712.6

【参考文献】