Institute of Mining Technology, Liaoning Technical University

在我国近水平复合煤层露天煤矿开采建设过程中，边帮压煤问题普遍存在，但通常只针对下部煤层回采问题进行研究。基于如何进行非工作帮高位煤层回采的问题，利用初步形成的内排土场为作业平台，考虑边帮边坡稳定性对回采模式的影响，提出了在边坡稳定的前提下沿边帮依次形成“敞口”、“斜坡道”并分阶段回采的模式。结合露天矿实际生产中需满足一定边坡角以确保边帮整体稳定的要求，以经济效益最优为判断准则，将分阶段回采模式分为回收阶段间煤柱和保留阶段间煤柱两种回采方式，并通过定量分析分别给出2者经济可行性的理论判据，随之讨论了2种回采方式所取得的净收益值与煤层厚度的关系。研究表明：不同回采方式的净收益值与煤层厚度大小正相关，因此可借助分析煤层厚度与净收益值的关系来选择较优回采方式，具体应用过程中回采方式的经济合理性需结合现场实际进行验算。以某露天矿为工程实例：①确定回收阶段间煤柱回采方式更经济，其净收益为6 385.320万元，非工作帮残煤回采剥采比为0.758；②可通过降低煤柱高度、增大采场和排土场所对应帮坡角的方式对保留阶段间煤柱回采方式进行改进以提高经济效益。成果可应用于类似露天矿，通过减少煤炭资源浪费，提升矿山企业整体经济效益的同时保证矿山安全、绿色、高效开采。

In the extraction of subhorizontal multiple coal seams using open-pit mining in China, the problem of coal seam in the high wall is commonly existed, but studies usually focus on the lower coal seam mining problem only. Based on the problem of implementing the mining of upper coal seams in non-working step, the initially formed inner refuse dump is used as the working platform, and the influence of the stability of the slope stability on the mining mode is also considered. It is proposed, in the premise of stable slope to form a pattern of “openings” and “ramps” stage by stage. In the actual production of open pit mines, combined with the requirement to meet the specific slope angle to ensure the overall stability of the highwall, making the maximum of economic benefit as the judgment criterion, the staged mining mode is divided into two types: recover coal pillars between the stages and retain coal pillars between the stages. By means of quantitative analysis, the theoretical criteria for the economic feasibility of the two are given, respectively, and the relationship between the net income obtained by the two mining methods and the thickness of the coal seam is discussed. The results shows that the net profit value (NPV) of different mining methods is positively correlated with the thickness of the coal seam, so the optimal mining method can be selected by analyzing the relationship between the thickness of the coal seam and the NPVs. The economic rationality of the mining method in the specific application should be checked according to the actual situation on site. Taking an open-pit mine as the engineering example: ① It is determined that the recovering coal pillar between stages is more economical, the net income is 63.853 million yuan, and extraction and stripping ratio of remnant coal in the non-working side is 0.758; ② By reducing the height of the coal pillar and increasing the corresponding slope angle of the stope and dump, economic benefit can be increased using the retaining coal pillar between stages. The results can be applied to similar open-pit mines. By reducing the waste of coal resources, the overall economic benefits of mining enterprises are improved while ensuring safe, green and efficient mining.

国家自然科学基金资助项目（51974144）；辽宁省揭榜挂帅资助项目（2021JH1/10400011）；辽宁工程技术大学学科创新团队资助项目（LNTU20TD-07）

曹　博，李青怡，汪　帅，等. 近水平复合煤层露天矿非工作帮高位煤层回采方案研究[J]. 煤炭科学技术，2023，51（8）：47−57

CAO Bo，LI Qingyi，WANG Shuai，et al. Research on mining plan of non-working high-level coal seam in open-pit mine with near-horizontal composite coal seam[J]. Coal Science and Technology，2023，51（8）：47−57