摘要
为解决淮南矿区松软低透气性突出煤层群条件下煤层构造复杂、多源瓦斯涌出、抽采流量衰减快、岩巷与钻孔成本高、低(超低)浓度煤层气利用率低等制约煤层气资源高效开发难题,通过分析煤层群条件下保护层卸压井上下立体抽采煤层气开发模式,提出较为适用的、与淮南矿区煤层群开采条件下煤与煤层气协调开发模式配套的六大关键技术,即:地面水平分段压裂井煤层气抽采技术,煤层气抽采巷道盾构快速施工技术,井下松软煤层煤层气强化抽采技术,地面采动区井卸压煤层气抽采技术,“以孔代巷”施工技术,低浓度煤层气梯级利用技术。配套关键技术应用表明:形成的碎软煤层顶板水平井分段压裂工艺及精细化排采技术,有效提高煤层气预抽产量;煤矿深井巷道全断面硬岩掘进机大幅提高巷道掘进效率,实现硬岩掘进自动化、少人化;井下水力压裂加砂、超高压水力割缝实现井下大区域卸压增透;Ⅲ、Ⅳ型地面采动区井在煤层群采动卸压瓦斯治理方面可以取代顶板高抽巷,且减少其他措施工程量,减小投入成本和工期;“以孔代巷”技术显著提升了复杂顶板中高位定向钻孔成功质量;低浓度煤层气梯级利用技术大幅减少了煤层气排放量;六大关键技术保障了淮南矿区安全生产,提高了煤、煤层气产量与煤层气利用水平。最后,针对地面水平井水力压裂煤储层改造技术作业成本高、产量低、范围小与采动井存在破断风险、超低浓度煤层气梯级利用规模小等问题,提出了深部煤层气精准地质导向、超大规模高效储层体积改造、抽采效果评价技术、采动区地面井稳定持续抽采技术、井下大面积智能水力化增透技术、“一井多用”协同抽采煤层气技术、全浓度煤层气综合利用技术的发展方向。
In order to solve the problems that restrict the efficient development of coalbed methane resources under the conditions of soft and low permeability outburst coal seams in Huainan Mining Area, such as complex coal seam structure, multi-source gas emission, rapid decline of drainage flow, high rock roadway and drilling costs, and low(ultra-low) concentration coalbed methane utilization rate, six key technologies suitable for the coordinated development mode of coal and coalbed methane under the condition of coal seam group mining in Huainan mining area are put forward, namely: coalbed methane extraction technology of ground level staged fracturing wells, shield rapid construction technology of coalbed methane extraction roadways, enhanced extraction technology of underground soft coalbed methane,coalbed methane extraction technology of pressure relief in ground mining area, the construction technology of "replacing roadways with holes", and cascade utilization technology of low concentration coalbed methane. The application of supporting key technologies shows that staged fracturing technology and refined drainage and production technology of roof horizontal wells in broken and soft coal seam have effectively improved the pre pumping production of coalbed methane;The full face hard rock roadheader in deep coal mine roadway greatly improves the roadway excavation efficiency, realizing the automation and less humanization of hard rock excavation;Sand adding of hydraulic fracturing and ultra-high hydraulic slotting have realized pressure relief and permeability enhancement in large areas underground coal mine;Type III and IV surface mining area wells can replace the roof high drainage roadway in the treatment of pressure relief gas in coal seam group mining, and reduce the coalbed methane drainage intensity of other measures;The technology of "replacing roadways with holes" has significantly improved the quality of successful directional drilling at middle and high levels in complex roof;Cascade utilization technology of low concentration coalbed methane has greatly reduced the emission of coalbed methane. The six key technologies have guaranteed the safe production in Huainan mining area, and comprehensively improved the output of coal and coalbed methane and the utilization level of coalbed methane. Six key technologies ensure the safe production in Huainan mining area, and comprehensively improved the output of coal and coalbed methane and the utilization level of coalbed methane. Finally, in view of the problems such as high operation cost, low production, small scope of hydraulic fracturing coal reservoir reconstruction technology for surface horizontal wells, and the risk of breakage of mining wells, and small scale of cascade utilization of ultra-low concentration coalbed methane, the development direction of deep CBM precise geological guidance, super large scale efficient reservoir volume transformation, pumping effect evaluation technology, stable and continuous pumping technology of surface wells in mining areas, underground large area intelligent hydraulic enhanced permeability technology, "one well with multiple uses" collaborative pumping CBM technology, and full concentration CBM comprehensive utilization technology are proposed.
作者
孔祥喜
唐永志
李平
王传兵
陈建
李琰庆
袁本庆
陈本良
叶敏
KONG Xiangxi;TANG Yongzhi;LI Ping;WANG Chuanbing;CHEN Jian;LI Yanqing;YUAN Benqing;CHEN Benliang;YE Min(Huainan Mining Group Corporation Limited,Huainan 232001,China;National Engineering&Technology Academy for Coal Mining,Huainan 232001,China;China Coal Technology Engineering Group Chongqing Research Institute,Chongqing 400037,China)
出处
《煤炭科学技术》
CAS
CSCD
北大核心
2022年第12期26-35,共10页
Coal Science and Technology
基金
国家科技重大专项资助项目(2016ZX05068)。
关键词
松软低透煤层
煤层气
地面水平井分段压裂
采动区地面井
强化抽采
梯级利用
以孔代巷
soft and low permeability coal seam
coalbed methane
staged fracturing of surface horizontal wells
surface wells in mining area
strengthen drainage
cascade utilization
replacing roadway with drilling
