College of Mining, Liaoning Technical University
Sichuan Gem Flower Xinsheng Oil and Gas Operation Service Co Ltd
College of Safety Science and Engineering, Xinjiang Institute of Engineering
No.1 Geological Institute of China Metallurgical Geology Bureau

坚硬顶板特厚煤层采场瓦斯涌出及运移特征具有特殊性,研究其特征是确定瓦斯治理方案、解决工作面瓦斯超限的基础。以大同矿区石炭系坚硬顶板特厚煤层开采为工程背景,运用理论分析、数值模拟及现场实测等方法研究采场瓦斯运移规律、抽采治理技术与参数。研究表明:坚硬顶板采动影响范围广、悬顶面积大,导致瓦斯异常涌出且积聚于顶板悬顶下的无风区域,工作面来压时瓦斯随悬顶垮落挤压进入工作面易引起瓦斯超限;工作面仅通过U型通风方式不能解决上隅角瓦斯超限问题,故提出采用高抽巷作为工作面瓦斯防治技术;首次定义了抽采权重概念,并基于抽采权重的动态调整,确定了高抽巷竖布置层位及抽采参数,高抽巷竖直距离工作面18m、水平距回风巷15m,最佳抽采负压为7kPa,最佳抽采权重范围为0.25~0.5,实现了上隅角瓦斯最高浓度仅为0.63%、瓦斯抽采浓度3.92%、工作面来压期间平均瓦斯抽采率可达80.8%的抽采效果。研究结果对坚硬顶板特厚煤层综放工作面瓦斯灾害治理具有重要的借鉴意义。

The unique characteristics of gas emission and migration in the extra-thick, hard-roofed coal seam present specific challenges. By studying these characteristics, it is possible to determine the gas control scheme and solve the problem of gas overflow at the coal face. Based on mining the Carbonifer- ous extra-thick hard-roof coal seam in the Datong mining area, this study investigates the gas migration law, mining and processing technology and parameters through theoretical analysis, numerical simulation and field measurement. The research shows that the complex roof's mining influence zone and the sus- pended roof zone are large, resulting in abnormal gas emission and accumulation areas lacking ventilation under the broken roof. When the working face is pressed, the gas enters the working facewith the collapse of the suspended roof, which quickly causes the gas to overflow. Merely employing U- shaped ventilation at the working face does not effectively address gas overflow in the upper corner, and the high-drainage roadway is proposed as the prevention and control technology of the working face gas. The concept of extraction weight is defined for the first time, and, the vertical layout layer and extrac- tion parameters of the high drainage roadway are determined based on the dynamic adjustment of extrac- tion weight. The vertical distance of the high drainage roadway is 18 m from the working face, and the horizontal distance is 15 m from the air return roadway. The optimum negative pressure for extraction is 7 kPa, and the optimum extraction weight range is 0.25-0.5. The maximum gas concentration in the upper corner is only 0.63 % , the gas extraction concentration is 3.92 % , and the average gas extraction rate during the pressure period of the coal face can reach 80.8 % . These research findings provide valua- ble insights for managing gas-related risks in fully mechanized coal faces with extra-thick hard roofs.

国家自然科学基金项目(52174185);山西省科技计划揭榜招标项目(20191101015)