大型铁矿山露天转地下开采过渡方案优化

合理确定大型铁矿山露天转地下开采过渡方案是露天转地下开采矿山关键技术问题之一。以庙沟铁矿为研究对象,首先在系统分析露天开采终了阶段,境界外矿体空间赋存状态的基础上,对不同区域的矿体开采进行方案设计,确定其基建时间节点与逐年产能;然后依据矿山开采现状与计划,结合挂帮矿体开采及覆盖层形成方案,分析矿山露天转地下开采过渡期阶段的时空相关性,提出了4种可行过渡方案;最后以露天转地下平稳过渡为目标,结合现有规范、标准,提出方案优化的评价指标为投资、资源利用可靠系数、产能平稳系数和开采安全系数。采用模糊综合评价理论对可行方案进行优化,确定了庙沟铁矿露天转地下开采过渡方案为:北端帮挂帮矿体采用崩落法、西边帮挂帮矿体采用平硐溜井联合开拓和回填形成覆盖层的过渡方案。

Optimization of Transitional Scheme from Open-pit to Underground Mining for Large-scale Iron Mine

It is one of the key technical problems for mines that transit from open-pit to underground mining to confirm transitional scheme from open-pit to underground mining rationally.Taking Miaogou iron mine as the research object，based on the systematically analysis of the stage of the end of open-pit mining and the occurrence of ore body which is outside the boundary，the infrastructure time and annual production capacity are firstly determined after designing the mining scheme of different districts.Then，on the basis of the exploitation status quo and plan，combing with the formation plan of covering layer and mining schemes of hanging wall ore body，four transition schemes were put forward by analyzing the time-space relationship of transitional period.Finally，in order to achieve a smooth transition，such indexes as investment，resource utilization coefficient，smooth capacity coefficient and mining safety coefficient are regarded as the evaluation index of scheme optimization combined with existing norms and standards.Fuzzy comprehensive evaluation theory is used to optimize the feasible schemes，and the transitional scheme determined finally is that the northern hanging wall ore body will be mined by caving method，and the western hanging wall ore body will be recovered by combination of footrill and chute，and then backfill to form the covering layer.