青东煤矿突出煤层水力冲孔消突试验研究

发布时间：2018-12-13 05:19

【摘要】：在我国煤炭井工开采的比例比较高,随着井工开采深度的增加,我国煤矿安全生产将面临地应力升高、瓦斯压力增大等严峻问题。针对青东煤矿松软低透气性煤层,煤体松软,煤体破坏程度较高,煤体透气性较差等特点,采用传统防突措施,现场抽排效果不佳,给现场煤与瓦斯突出防治工作带来诸多困难,因此采取水力冲孔措施提高煤体透气性,提高瓦斯抽采效率是防治煤与瓦斯突出、提高煤炭安全高效开采行之有效的方法。本文在分析水力冲孔过程动力特性、影响水射流破煤因素的基础上,利用ANSYS/LS-DYNA数值模拟对水射流侵蚀煤体动态过程分析,并分析计算水力冲孔对钻孔周围煤体的应力、应变变化影响。在青东煤矿728工作面顶板岩巷实施水力冲孔措施工业试验,平均单孔冲煤量1.3t,水力冲孔前后钻孔直径扩大到593.4mm,较冲孔前增大6.3倍。对水力冲孔后瓦斯抽采浓度和瓦斯抽采纯量考察,单孔最大瓦斯浓度冲孔后峰值6.53%,较冲孔前平均值提高6.5倍；最大瓦斯抽采纯流量冲孔后最高值0.4m3/min,比冲孔前增加0.33m3/min,提高5.7倍；试验区最大残余瓦斯压力0.21MPa,最大残余瓦斯含量3.17m3/t,验证水力冲孔的卸压增透效果。结合在煤巷工作面掘进过程中的钻屑瓦斯解吸指标K1(mL/gmin1/2)最大值为0.11,最大钻屑量Smax(Kg)最大值为3.9,"縣2(Pa)最大值为80,瓦斯放散初速度△p最大值为8mmHg,煤体坚固性系数大于0.7等突出指标进行了分析,顶板巷下向钻孔水力冲孔消突效果显著,该技术为82采区的728工作面投产节省了时间,经济效益显著。
[Abstract]:The proportion of coal miners is relatively high in our country. With the increase of mining depth, the safety production of coal mines in our country will face some serious problems, such as the increase of in-situ stress and the increase of gas pressure. In view of the characteristics of soft and low permeability coal seam in Qingdong coal mine, the coal body is soft, the destruction degree of coal body is high, and the gas permeability of coal body is poor, the effect of field drainage is not good by adopting traditional anti-outburst measures. It is difficult to prevent coal and gas outburst on the spot, so it is an effective method to prevent coal and gas outburst and to improve the safety and efficiency of coal mining by taking hydraulic punching measures to improve the permeability of coal body and improve the efficiency of gas extraction. On the basis of analyzing the dynamic characteristics of hydraulic punching process and influencing factors of water jet breaking coal, the dynamic process of water jet eroding coal body is analyzed by ANSYS/LS-DYNA numerical simulation, and the stress of hydraulic punching on coal body around borehole is analyzed and calculated. The effect of strain variation. The industrial test of hydraulic punching measures in the roof rock roadway of No. 728 working face of Qingdong Coal Mine shows that the average coal flushing capacity of single hole is 1.3 t, the diameter of borehole before and after hydraulic punching expands to 593.4 mm, which is 6.3 times larger than that before punching. The concentration of gas extraction and the scalar amount of gas extraction after hydraulic punching are investigated. The peak value of the maximum gas concentration in single hole after punching is 6.53, which is 6.5 times higher than the average before punching. The maximum value of 0.4m3 / min after punching was increased by 0.33m3 / min, which was 5.7 times higher than that before punching. The maximum residual gas pressure is 0.21 MPA and the maximum residual gas content is 3.17 m3 / t in the test area. The maximum value of gas desorption index K1 (mL/gmin1/2) is 0.11, the maximum value of Smax (Kg) is 3.9, the maximum value of county 2 (Pa) is 80, the maximum value of K1 (mL/gmin1/2) is 0.11 and the maximum value of Smax (Kg) is 3.9, respectively. The maximum initial velocity p of gas release is 8mm Hg, and the coal body firmness coefficient is greater than 0.7. The outburst suppression effect of hydraulic punching in the bottom of roof roadway is remarkable. This technique saves time for 728 working face in 82 mining area. The economic benefit is remarkable.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TD713

【参考文献】