Study On Optimizing Transition Scheme Of Slope-to-Depth Open-pit Mining In Dumu Mining Area

At present,a large number of open-pit mines have entered the middle and late stages,and high-altitude mining has been switched to pit mining.A series of new problems such as new boundary delineation,rock transportation and ore crushing after the expansion of the boundary mining have restricted the safe and efficient mining of the hillside to deep concave open pit mining.Dumu Mining Area of Gongchangling Opencast Iron Mine of Anshan Iron and Steel Group has been one of the important iron ore raw material production bases since it was put into production in the 1950 s.In recent years,the investment in geological and mineral exploration in the North part of Dumu Mining Area has greatly changed the deposit form and reserves of the ore body,which has changed the overall layout of the iron ore resources,resulting in a lot of waste of resources and energy,and affecting the continuous development of the output of the Iron Mine.In order to solve the problems,we have established a three-dimensional model of the mining area and calculated reserves,through the second optimization of the mining realm and the optimization of the transportation road,we have obtained a new optimized realm and increased the high-level minerals.The main research results are as follows:(1)Through digital processing of mine quarry and drilling information,a special spatial database of ore body grade and a digital model of ore body grade space in Dumu mining area have been established.(2)Through the study of slope stability,the influence of slope angle change on the safety factor was analyzed,and it was found that the safety factor of section 1 and 2 in the northern part of the mining area is small,especially the section 2,which is close to the critical value.(3)An optimized calculation based on geological reserves was carried out.After the optimization,the new realm increased a net amount of high-level ore of 0.1882 billion tons,and the service life of the mine was increased by 7.5 years.Based on the optimized calculation results of the production ore volume,the service life was increased by 5.5 years.(4)From the stope exit to the rock discharge point,a total of 6 rock removal schemes were considered,the routes were optimized,and the costs were calculated separately.It is considered that the plan of the transportation distance station dominated by the boundary is the most beneficial for rock discharge.It is the most economically reasonable and the most beneficial to all aspects of expanding the border.The rock drainage road in the Dumu mining area has been adjusted.The new rock drainage road is currently shortened by 1km(actual distance),and the cost can be reduced by 162.228 million yuan compared with the use of the original rock drainage road.