中国煤矿井下规模化抽采煤层气技术模式及适应条件研究

Study on technical mode and its adaptive conditions of underground scale extracting coalbed methane in coal mine of China

我国煤层气储层条件具有"三低一高"的特点,地面井抽采和井下抽采两者相互结合,取长补短是我国煤层气规模化开发的必由之路。本文通过对山西晋城、安徽两淮、重庆松藻3个示范矿区井下采煤和采气工程相互关系的研究,得出了煤矿井下规模化抽采煤层气技术模式划分方法和依据为煤层渗透率、煤层赋存条件和煤层开采顺序;煤矿井下采煤与采气工程相互衔接的关键节点为是否消除了煤层的煤与瓦斯突出危险性、是否实现了煤层瓦斯抽采达标和是否能避免工作面上隅角瓦斯超限;基于对煤矿井下规模化抽采煤层气技术模式和采煤-采气工程时空衔接关系的研究成果,结合各示范矿区井下煤层气抽采技术的应用现状,构建了3种典型模式对应的技术体系框架;从煤层条件、瓦斯条件和地质条件3个方面建立了典型井下规模化抽采煤层气技术的适应条件。最后,结合我国煤矿安全生产实际,提出了煤矿井下规模化抽采煤层气存在的技术瓶颈及新设想。

The reservoir conditions of the coalbed methane in our country are characterized by "three low and one high",the combination of ground well extraction and underground extraction which complement each other is the only way for the large-scale coalbed methane development in China. According to the relationship research between underground coal mining and gas extraction engineering of the three model mining areas of Jincheng, Lianghuai and Songzao, it is concluded that the key impact factors of scale underground extraction technology are the coal seam permeability, the occurrence condition of coal seam and the seam mining sequence. Critical joint nodes of underground coal mining and gas extraction project are whether or not the outburst danger of coal seam and gas is eliminated, whether or not gas extraction meets standard and whether or not gas overrun in upper corner could be avoided. Based on the research results of largescale coalbed methane extraction technical patterns in coal mines and the space-time connection of coal mining and gas extraction, combine with the present situation of various coals extraction technology, three types of technical system corresponded to typical extraction patterns are built. The adaptive conditions of the typical underground large-scale methane extraction technology is established from three aspects of coal seam conditions, gas conditions and geological conditions.Finally, combined with the actual safety of coal mines in our country, the technical bottlenecks and new ideas for the large-scale extraction of coalbed methane in coal mines are put forward.