本文關(guān)鍵詞： 穿層孔 低透氣性煤層 水力壓裂 卸壓增透 數(shù)值模擬　出處：《安徽理工大學》2014年碩士論文　論文類型：學位論文

【摘要】：本文針對李嘴孜煤礦水力壓裂卸壓增透技術(shù)的研究,采用理論分析、數(shù)值模擬和現(xiàn)場試驗相結(jié)合的方法,以A1煤層32321底板巷區(qū)域進行現(xiàn)場試驗研究了水力壓裂卸壓增透效果。結(jié)果表明通過水力壓裂措施能提高A1煤層的透氣性系數(shù)、加強內(nèi)部瓦斯氣體的流動、濕潤煤體降塵作用、提高抽采率降低煤層突出危險性的目的。 對水力壓裂的力學特性進行了分析,采用大直徑的鉆孔進行水力壓裂時可增加鉆孔四周的卸壓區(qū)域,加大鉆孔四周的煤體的暴露表面積,加強內(nèi)部瓦斯氣體的流動,起到增加煤層透氣性的效果。分析了鉆孔的起裂位置和起裂所需壓力,得出：起裂壓力的臨界值 在數(shù)值模擬實驗中,模擬了不同埋深的起裂壓力,得出煤巖體的起裂時的注水壓力隨著煤層埋深而增加,壓裂鉆孔起裂壓力數(shù)據(jù)進行回歸分析得到煤層埋深與起裂壓力的關(guān)系式：y=10.351e0.0014x,R2=0.9837,計算得A1煤層處的起裂壓力24.92Mpa。600m處的壓裂半徑在12.665-14.965m；500m處的13.683-16.876m；400m處壓裂半徑在16.011-18.846m；卸壓區(qū)域的煤層滲透系數(shù)提高了2.5倍左右。 現(xiàn)場試驗中,通過對A1煤層的壓裂試驗,對壓裂工藝流程和壓裂前后的安全措施進行了詳細設(shè)計,分走向和傾向方向上設(shè)計了考察方案。傾向上最大影響半徑50m、走向上最大影響半徑70m,水力壓裂后對瓦斯抽采濃度和抽采量的提高十分明顯,抽采濃度在36%～56%之間,平均抽采混合流量濃度0.3lm3/min,平均抽采純流量則基本穩(wěn)定在0.16m3/min,單孔純流量約為0.013m3/min,壓裂后干管抽采平均濃度為壓裂前的1.7倍；壓裂后單孔平均抽采純量為壓裂前的3.5倍,壓裂影響區(qū)域煤層透氣性系數(shù)達0.372m2/(MPa2·d)較原始0.062m2/(MPa2·d)提高了6倍。 對李嘴孜煤礦A1煤層層內(nèi)卸壓增透技術(shù)的研究,結(jié)合現(xiàn)場實測,驗證了力學分析結(jié)果和數(shù)值模擬計算結(jié)果的準確性。
[Abstract]:Aiming at the research of hydraulic fracturing and anti-permeability technology in Lizuizi Coal Mine, this paper adopts the method of combining theoretical analysis, numerical simulation and field test. In this paper, the anti-permeability effect of hydraulic fracturing is studied in 32321 floor roadway area of coal seam A1. The results show that hydraulic fracturing measures can improve the permeability coefficient of coal seam A1, strengthen the flow of gas gas in coal seam, and reduce dust of wet coal body. The purpose of increasing extraction rate and reducing coal seam outburst risk. The mechanical characteristics of hydraulic fracturing are analyzed. When hydraulic fracturing is carried out with large diameter borehole, the pressure relief area around the borehole can be increased, the exposed surface area of coal around the borehole can be increased, and the flow of gas gas inside the borehole can be strengthened. This paper analyzes the starting position of borehole and the pressure required for the initiation of the crack, and obtains the critical value of the initiation pressure of the coal seam with the effect of increasing the permeability of the coal seam. In the numerical simulation experiment, the initiation pressure of different burying depth is simulated, and the water injection pressure of coal and rock mass increases with the depth of coal seam burying. The regression analysis of fracture initiation pressure data obtained the relationship between coal seam burying depth and fracture initiation pressure, and calculated the fracture radius of A 1 coal seam at 24.92 Mpa.600m, 13.683-16.876m400m at 12.665-14.965mand 16.011-18.846m, respectively, and the fracturing radius was 16.011-18.846m, and the fracture radius was 24.92Mpa.600m at A1 coal seam, and the fracturing radius was 16.011-18.846m at 12.665-14.965mb.500m, and the fracture radius was 16.011-18.846m at the point of 12.665-14.965mb / 500m. The permeability coefficient increased about 2.5 times. In the field test, the fracturing process and safety measures before and after fracturing are designed in detail through the fracturing test of A1 coal seam. The investigation plan is designed in the direction of strike and inclination. The maximum influence radius on inclination is 50 m, and the maximum influence radius on strike is 70 m. After hydraulic fracturing, the concentration and quantity of gas extraction are obviously increased, and the extraction concentration is between 36% and 56%. The average pumping flow rate was 0.3lm 3 / min, the average pumping pure flow rate was 0.16m3 / min, the single hole pure flow rate was 0.013m3 / min, the average extraction concentration after fracturing was 1.7 times higher than that before fracturing, and the average extraction scalar amount after fracturing was 3.5 times higher than that before fracturing. The permeability coefficient of coal seam in the area affected by fracturing is 0.372m-2 / m-2 路d), which is six times higher than that of original 0.062m2 / m-1 / m-2 路d). Based on the research of pressure relief and antireflection technology in A1 coal seam of Lizuizi coal mine, the accuracy of mechanical analysis and numerical simulation results is verified by field measurement.
【學位授予單位】：安徽理工大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TD712

【參考文獻】

相關(guān)期刊論文 前10條

1 蔣惺耀,王允誠,孟慕堯,朱過才;水力壓裂機理研究[J];成都地質(zhì)學院學報;1983年01期

2 李同林;水壓致裂煤層裂縫發(fā)育特點的研究[J];地球科學;1994年04期

3 劉萬倫;水力沖刷防突技術(shù)在突出煤層掘進工作面的應(yīng)用[J];礦業(yè)安全與環(huán)保;2004年04期

4 陽友奎,肖長富,吳剛,邱賢德;不同地應(yīng)力狀態(tài)下水力壓裂的破裂模式[J];重慶大學學報(自然科學版);1993年03期

5 王兆豐;許彥鵬;劉軍;;水力擠出快速消突措施在大眾煤礦的應(yīng)用[J];河南理工大學學報(自然科學版);2007年02期

6 張志勇;;井下水力壓裂強化抽放技術(shù)應(yīng)用[J];礦山機械;2010年12期

7 林柏泉;李子文;翟成;比強;溫永宇;;高壓脈動水力壓裂卸壓增透技術(shù)及應(yīng)用[J];采礦與安全工程學報;2011年03期

8 連承波,李漢林;地應(yīng)力對煤儲層滲透性影響的機理研究[J];煤田地質(zhì)與勘探;2005年02期

9 王國鴻;徐贊;;水力壓裂技術(shù)提高低透氣性煤層瓦斯抽放量淺析[J];煤礦安全;2010年08期

10 代志旭;;高壓水力壓裂技術(shù)在瓦斯綜合治理中的研究與應(yīng)用[J];煤炭工程;2010年12期

，

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