高级检索

急倾斜煤组煤岩放出流动规律及控制

Flow law and control of coal-rock drawing in steeply inclined coal seam groups

  • 摘要: 急倾斜近距离煤层群水平分段开采,受倾角与边壁效应影响,煤岩流动规律复杂、放出率低,严重制约该类煤层的安全高效开采。以新疆天顺煤矿水平分段大段高综放联合开采工作面为工程背景,采用数值计算方法,系统研究了不同放煤工艺对煤岩流动规律、放出体形态、放出率的影响机制,提出了以控制散体间隔岩层优先放出为核心的高效放煤控制技术,优化了联合综放工作面放煤工艺,并结合相似模拟与工业性试验验证了放煤工艺的科学性。结果表明:在急倾斜联合工作面开采过程中,煤岩放出体流动规律与放出率受顶、底板倾斜边壁与间隔岩层破碎矸石影响,下层散体顶煤在间隔岩层破碎矸石与底板的夹持作用下,导致联合开采工作面底板侧三角煤远大于顶板侧,上层散体顶煤受间隔岩层影响较小;根据不同放煤工艺下煤岩放出情况,提出优先保证散体间隔岩层放出,减少其对下煤层散体顶煤约束效应的控制技术,进而提高急倾斜联合开采工作面煤岩放出率;最后结合天顺矿井中组煤地质条件,提出采用顶板侧向底板侧多轮间隔放煤工艺,可有效削减间隔岩层破碎矸石对煤层的约束效应。根据现场工业性试验验证,采用该放煤工艺可使工作面日产量相较于其余放煤工艺提升最高达24.5%,大幅减少顶、底板侧三角煤损失。

     

    Abstract: The horizontal slicing mining of steeply inclined closely spaced coal seam groups is characterized by complex coal-rock flow patterns and low recovery rates due to the influence of seam dip angle and boundary effects, which severely restricts the safe and efficient mining of such coal seams. Using the horizontal slicing combined fully mechanized top-coal caving mining face with large slicing height at Xinjiang Tianshun Coal Mine as an engineering background, this study employs numerical simulation methods to systematically investigate the influence mechanisms of different drawing processes on coal-rock flow patterns, drawing body morphology, and recovery rate. An efficient drawing control technology is proposed, focusing on the prioritized drawing of the fragmented parting rock stratum. The drawing process for the combined working face was optimized and validated through similarity simulations and industrial tests. Results indicate that during the mining of the steeply inclined combined working face, the flow law of the drawing body and the recovery rate are governed by the inclined roof and floor boundaries, as well as the fragmented gangue from the parting rock stratum. The lower loose top coal is strongly constrained by the combined effects of the fragmented gangue and the floor, resulting in an asymmetric distribution of corner coal, which is significantly greater on the floor side than on the roof side, while the upper loose top coal is less affected by the parting rock stratum. Based on the coal-rock drawing results under different drawing processes, a control strategy is proposed that prioritizes the efficient drawing of the fragmented parting rock stratum to reduce its restraining effect on the lower loose top coal, thereby improving the overall coal-rock recovery rate in the steeply inclined combined working face. Finally, considering the geological conditions of the middle coal group at Tianshun Mine, a multi-round interval drawing process from the roof side to the floor side is recommended. This optimized process effectively reduces the constraining effect of the fragmented gangue from the parting rock stratum on the coal seams. Field industrial tests demonstrate that adopting this drawing process can increase daily face output by up to 24.5% compared to other processes, while significantly reducing corner coal loss on both the roof and floor sides.

     

/

返回文章
返回