赵继展.井下瓦斯抽采钻孔机械造穴技术研究[J ].矿业安全与环保,2015,42(6):66-68.
文章编号:1008-4495(2015)06-0066-03
井下瓦斯抽采钻孔机械造穴技术研究
赵继展
(中煤科工集团西安研究院有限公司,陕西西安710054)
摘要:为了解决低渗透性煤层瓦斯抽采困难的问题,通过理论分析和数值模拟研究了提高钻孔瓦斯抽采效率的主要途径,借鉴煤层气洞穴完井工艺技术,研制了以钻机给进和旋转为动力二适用于井下瓦斯抽采钻孔的开合机械臂式造穴工具,形成了可在井下煤层瓦斯抽采钻孔内定点位置实现Φ600mm 洞穴的工艺技术三在芦岭煤矿的2组造穴钻孔工程试验表明,机械造穴技术能够明显提高钻孔瓦斯抽采效果,与同一地点的常规瓦斯抽采钻孔相比,造穴钻孔单孔瓦斯抽采浓度提高了2.31~4.00倍,纯瓦斯流量提高了2.63~5.11倍三
关键词:低渗煤层;瓦斯抽采;机械造穴;数值模拟
中图分类号:TD712 文献标志码:B 网络出版时间:2015-12-0111:51
网络出版地址:http ://https://www.doczj.com/doc/3e11683119.html, /kcms /detail /50.1062.TD.20151201.1151.032.html
Study of Mechanical Cavity-forming Technology for Underground Gas Drainage Hole Drilling
ZHAO Jizhan
(China Coal Technology and Engineering Group Xi an Research Institute,Xi an 710054,China)
Abstract :In order to solve the problem of difficult gas drainage from the coal seam with low permeability ,study was carried
out on the main ways for improving gas drainage efficiency by theoretical analysis and numerical simulation ,coal-bed methane well completion technology was used for reference ,a cavity-forming tool with a retractable arm was developed ,which took the drill feed and rotation as the power and was suitable to drill gas drainage holes ,with this cavity-forming tool ,Φ600mm cavity-forming technology can be achieved at a fixed position in underground gas drainage holes.The cavity-forming drilling test in Luling Coal Mine showed that the mechanical cavity-forming technology for coal gas drainage drilling can significantly improve the efficiency of gas drainage ,and compared with the conventional gas drainage drilling ,the gas concentration of a single hole with the cavity-forming drilling technology increased by 2.31to 4.00times and the pure gas flow increased by 2.63~5.11times.Key words :coal seam with low permeability ;gas drainage ;mechanical cavity-forming ;numerical simulation 收稿日期:2015-04-10;2015-07-29修订
基金项目:国家科技重大专项资助项目(2011ZX05040);
国家自然科学基金项目(41202122);中国煤炭科工集团有限
公司科技创新基金项目(2011MS006)
作者简介:赵继展(1978 ),男,河北宣化人,博士研究
生,从事煤矿安全二瓦斯地质工作三E -mail :zhaojizhan @
https://www.doczj.com/doc/3e11683119.html, 三 我国煤层渗透率低,一般为(0.1~0.001)?10-3μm 2[1],随着煤炭开采逐渐向深部发展,地应力增加,煤层的渗透率进一步降低三为改善低渗透性
煤层瓦斯抽采困难的现状,近年来有关研究人员提
出了一系列的强化增透措施,如水力压裂[2-3]二高压
水射流割缝[4]二深孔爆破[5]等,取得了一定的效果,但也存在诸多局限性三水力压裂和高压水射流割缝
等需配置大型设备,对操作过程要求较高;而深孔爆破技术实施过程中工艺参数计算和控制复杂,且易产生哑炮而留有安全隐患,因此仍然需要寻求一种简单有效的瓦斯强化抽采技术三研究和实践表明,增大钻孔直径能有效地卸压消突二提高瓦斯抽采效果[6-7],但大直径抽采钻孔(孔径大于150mm)施工工艺复杂二成本较高[8],我国井下瓦斯抽采钻孔孔径局限在300mm 以内三裸眼洞穴完井是地面煤层气开发的一种特殊完井方式,在增大煤层暴露面积二卸压增透二提高煤层产气速率和产气总量等方面具有显著效果[9-10]三裸眼洞穴完井技术在美国的圣胡安二大绿河等盆地[11]和我国的沁水盆地都得到了应用[12]三在此,借鉴地面煤层气裸眼洞穴完井技术原理,通过分析井下抽采钻孔特性,开展井下瓦斯抽采四66四Vol.42No.6Dec.2015 矿业安全与环保MINING SAFETY &ENVIRONMENTAL PROTECTION 第42卷 第6期2015年12月