高危空区群下地下转露天协同开采技术研究

Study on Synergetic Mining Technology of Underground to Open Pit under High Risk Goaf Group

柿竹园矿地表塌陷给井下生产带来了一系列难题,如地表泥水混入井下导致矿石贫化且影响选矿,塌陷区北部和东北部高陡悬崖导致地表滚石和滑坡显现,塌陷区南部形成大跨度悬臂空区,不稳定间柱与大采空区形成高危空区群、含矿大块堵塞出矿巷等。根据矿山现场调研、实测绘图和岩移研究,通过3Dmine软件建模,精准划分了塌陷区、过渡型空区、高危明空区、外围空区等。为解决该矿生产难题,提出了井下与露天协同开采技术方案:首先采用低品位矿石充填塌陷区周边的高危空区群;再禁止塌陷区南部井下采出矿石,并在地表采用深孔爆破技术崩落悬臂矿岩;然后对塌陷区北部和东北部高陡悬崖实施地表削坡剥离和利用低品位矿石回填塌陷区;最后在6~8 a内由地下开采过渡到露天开采,并探索性回采塌陷区内的巨块矿石。为减少前期剥离投入、缓解剥离境界外修路难的问题,结合环山贴坡布置螺旋型阶梯状剥离台阶、道路融入山坡剥离境界等思路,利用3Dmine软件建模研究,优化确定了720剥离境界。同时,通过生产计划上图标识,及时更新协同作业区,实时微震监测地下采区和GPS监测塌陷区岩移等技术措施,实现了矿山协同开采的动态监测与预警。研究表明:所提出的优化剥离境界思路和一系列露天与井下协同开采技术方案,解决了该矿当前的生产难题,为该矿露天与井下协同作业提供了安全保障,可为类似矿山提供有益参考。

The surface collapse of Shizhuyuan Mine has brought a series of problems to the underground production,such as the surface mud water mixed into the underground leads to ore dilution and affects mineral processing,the high steepcliffs in the north and northeast of the collapse area lead to the surface rolling stones and landslides,the large-span cantileverempty area in the south,the formation of high-risk goaf groups between unstable pillars and large goafs,and the ore bearingblocks block the ore roadway,etc..According to the field survey,field survey mapping and rock movement research,through3 Dmine software modeling,the collapse area,transition type goaf,high-risk open goaf and peripheral goaf are accurately di-vided.In order to solve the production problem of the mine,the technical scheme of synergetic mining of underground andopen pit is put forward:firstly,the low-grade ore is used to fill the high-risk empty area around the collapse area;secondly,itis forbidden to mine ore underground in the south of the subsidence area,and the cantilever ore-rock is collapsed by thedeep hole blasting technology on the surface;then the high steep cliffs in the north and northeast of the collapse area arestripped on the surface and the subsidence area is backfilled with low-grade ore;finally,the transition from underground min-ing to open-pit mining in 6~8 years,and tentative mining of large ore in the subsidence area.In order to reduce the invest-ment in the early stage of stripping and ease the difficulty of road construction beyond the boundary of stripping,combingwith the idea of arranging spiral step-by-step stripping steps around the mountain and embedding the road into the step of thehillside stripping boundary,the 720 stripping boundary is optimized and determined by using 3 Dmine software modeling study.At the same time,through the technical measures such as marking the production plan on the map,updating the coop-erative operation area in time,monitoring the underground mining area with real-time micro earthquake and monitoring therock movement in the subsidence area with GPS,the synergetic mining operation of the mine has realized the dynamic moni-toring and early warning. The study results show that the idea of optimizing stripping boundary and a series of technicalschemes of open-pit and underground synergetic mining are put forward,which solve the current production problems of themine,provide safety guarantee for the open-pit and underground synergetic operation of the mine,and provide useful refer-ence for similar mines.