【作者】 刘国俊；

【导师】 刘明举； 刘彦伟；

【作者基本信息】 河南理工大学 ， 矿业工程， 2011， 硕士

【摘要】 水力冲孔是采用岩石巷道做为安全屏障,通过施工穿层钻孔,利用喷嘴的切割和高压水射流的冲击作用冲出部分煤体与瓦斯,引起钻孔周边煤岩体应力降低、裂隙伸展、扩张与贯通,使钻孔周围一定范围内煤体充分卸压增透,从而强化瓦斯抽放效果,实现采掘工作面安全快速消突与掘进的目的,是一种具有广阔应用前景的防突技术措施。针对淮南矿区煤层松软、透气性低、瓦斯含量高、瓦斯压力大的特点,特别是深部无解放层可采的低透气性突出危险性煤层掘进速度缓慢、采掘接替紧张等问题,本文以达到严重突出危险性煤层安全快速高效掘进与揭煤为目标,采用理论分析、计算机数值模拟与工业性现场试验等手段相结合的方法,分析了水力冲孔的卸压增透理论,经过现场试验,确定了适合淮南矿区典型突出煤层的水力冲孔技术参数及工艺过程,应用瓦斯压力法和瓦斯流量法对水力冲孔的有效影响半径进行了考察,其变化范围为3.5m～9.32m,通过对比水力冲孔前后瓦斯涌出量、瓦斯流量、瓦斯流量衰减系数及煤层透气性等瓦斯基础参数,分析了水力冲孔的卸压增透效果,并建立了适合淮南矿区的水力冲孔卸压增透评价指标体系。介绍了水力冲孔的消突原理,通过数值模拟软件Rockscience Phase~2,模拟了不同钻孔间距情况下,穿层水力冲孔钻孔间应力场的分布情况及卸压范围,并以顾北矿6-2煤层赋存条件为研究对象,对水力冲孔的技术参数进行了优化。对水力冲孔消突效果的有效性进行了考察,各试验矿井实施水力冲孔措施后,瓦斯抽放效果大大提高,切实消除了试验工作面的突出危险性,实现了工作面的快速安全采掘,而且掘进期间预测效检超标率低,工作环境大为改善,没有出现任何瓦斯动力现象,充分显示了其消突效果的可靠性与有效性。更多还原

【Abstract】 The hydraulic flushing is a kind of gas outburst prevention technological measure with wide applications prospects in the future, which make rock roadway as security barrier, after the seam-crossing borehole has drilled over, coal and gas are flushed out by the effects of incision from jet and impact of high pressure water jet, the stress around the borehole will drop down, and fissure stretch out、expand and induce with each other, the coal would have a full pressure-relief and permeability improvement in some range of the borehole, the effect of gas drainage will be improved and strengthened powerfully, to eliminate the risk of gas outburst from working face will come ture easily. In allusion to the coal seams characteristics of Huainan coal mine? soft coal seam、low permeability、high gas content and high gas pressure, particularly to the problem of low excavation rate and the conflict of exploitation and mining for the deep buried coal seams with low permeability and gas outburst danger, which have no protective seams to mine, in this article, in order to achive the rapid、safe and efficient excavation in the coal seams with serious gas outburst potential, by the method of combination of theoretical analysis、computer numerical simulation and field test, the theory of pressure relief and permeability improvement by hydraulic flushing was analysised, suitable technique parameters and process of hydraulic flushing for Huainan mining area was determined, influence radius for hydraulic flushing was investigated by the means of gas pressure and gas flow, and the range of its influence radius is about 3.5m～9.32m, compare the gas basic parameters such as the gas emission quantity、gas flow volume、damping factor of gas flow and the permeability of the coal seam pre-and-post hydraulic flushing, the effect of pressure relief and permeability improvement for hydraulic flushing was analysised, and the evaluation index system of pressure relief and permeability for hydraulic flushing in Huainan mining area was established. The theory of gas outburst elimination for hydraulic flushing was introduced, stress field distribution and the range of pressure relief around seam-crossing borehole in the condition of different distance between tow boreholes are simulated by the software of Rockscience Phase2, the technological parameters of the hydraulic flushing was optimized based on the storage situation of the 6-2 coal seam in Gubei coal mine.Validity of outburst elimination with hydraulic flushing was checked after hydraulic flushing carried out, the effect of gas drainage improved greatly, outburst danger potential is eliminated practically and efficiently , the driving speed of the working face is more rapidly than before, and the over standard rate of validity check index is reduced, working environment is greatly improved, and no gas dynamic phenomenon occurred in the driving process of working face, these fully demonstrate the validity and reliability of the hydraulic flushing.更多还原