基于大功率定向钻进技术与装备的发展和矿井瓦斯防治技术的提升，保德煤矿先后创造了2311、2 570、3 353 m井下顺层定向长钻孔瓦斯抽采施工纪录，为矿井实施超大区域瓦斯治理技术提供了基础条件。以保德煤矿8号煤的煤层气防治为研究对象，基于超长工作面区域瓦斯治理需要，依据区域范围及预抽时间的不同，分别采用井上井下联合抽采、盘区超前大区域预抽、掘进工作面主巷羽状钻孔大区域预抽、采煤工作面大区域递进式预抽等措施对采掘区域内煤层气进行了大面积超前预抽，为煤层气治理提供了充裕的时间和空间，确保了抽采达标所必备的时间条件；针对8号煤层透气性低、抽采衰减快的问题，采用定向钻孔分段压裂增透技术并辅以高效封孔工艺技术，实现了煤巷掘进前和工作面回采前煤层气的高效治理；针对矿井超长工作面回采后形成的大范围采空区瓦斯异常涌出问题，提出并实施了大范围采空区平衡卸压抽采技术，有效地阻止了采空区瓦斯涌入采掘空间。实践表明：保德煤矿8号煤层通过实施超大区域瓦斯治理技术措施，煤层气预抽率大于30%，切实有效地解决了工作面采掘期间的瓦斯涌出治理问题，矿井生产全过程瓦斯抽采达标；采掘工作面月产量达80万t，掘进工作面月单进尺560 m以上，实现了高瓦斯矿井长周期安全高效生产，实践证实了超大区域瓦斯治理技术具有显著的安全和经济效益。

Based on the development of high-power directional drilling technology and equipment and the improvement of mine gas prevention technology, BaodeCoal Mine has successively created the record of gas extraction in 2 311, 2 570 and 3 353 m underground directional long borehole, which provides the basic conditions for the implementation of gas control technology in super large area.Taking No.8 coal seam gas prevention and control in Baode coal mine as the research object, based on the needs of gas management in the area of ultra-long working face, according to the difference of regional scope and pre-draining time, the combined extraction of the well and the pre-drainage of the large area are adopted respectively. Measures such as large-area pre-drainage of pinnate boreholes in the heading face and large-area progressive pre-drainage of coal mining face have carried out large-area advanced pre-drainage of the coalbed methane in the mining area, providing sufficient time space for coal seam gas pre-drainage, to ensure the necessary time conditions for the pre-drainage to meet the standard; in view of the relatively low permeability of No. 8 coal seam and the rapid attenuation of drainage, the use of directional drilling and staged fracturing and anti-reflection technology is supplemented by high-efficiency sealing technology. In order to solve the problem of the abnormal gas emission problem in the large-scale gob formed after the ultra-long working face of the mine, the large-scale gob balanced pressure relief was proposed and implemented. The extraction technology effectively prevented the gas from the goaf from flowing into the mining space. Engineering practice shows that the coal seam gas pre-drainage rate is greater than 30% through the implementation of super-large area gas treatment technical measures in  No. 8 coal seam of Baode Coal Mine, which effectively solves the problem of gas emission control during the mining of the working face, and the gas drainage in the whole process of mine production meet the standard; the monthly output of the mining face reaches 800 000 tons, and the monthly excavation of the tunneling face is more than 560 m, which realizes the long-term safe and efficient production of high gas mines. Practice has proved that the super-large area gas treatment technology has significant safety and economic benefits. 

0 引言

1 矿井概况

   1.1 基本情况

   1.2 瓦斯赋存情况

   1.3 瓦斯治理存在的难题

2 超大区域瓦斯治理技术

   2.1 超大区域瓦斯抽采方案

   2.2 超大区域瓦斯高效抽采技术

3 瓦斯治理效果分析

   3.1 井上下联合正压排采

   3.2 超大区域预抽采效果分析

   3.3 大区域超前预抽采对巷道掘进的影响

   3.4 综采工作面大区域超前抽采效果分析

   3.5 采空区大区域高位钻孔抽采效果分析

4 结论