Technical Research Of Fluorite Ore For The Second Mining Area Filling Method In Xilinhot Mine

Ore body of Xilinhot fluorite ore mine present vein output.Fluorite grade is average of 63.21%,for the value of high rich ore bodies.The thickness of ore body is 2?5m,and the angle of it is 80°?90°,for steeply inclined thin to medium thick ore body.Mine exploitation by short-hole shrinkage method,exists in the production of large ore dilution loss,low production capacity and security production conditions.At the same time,the mine is located in the grassland,the surface need to be protected,in need of improvement of mining method,in order to reduce ore loss and dilution to protect the surface environment.Through field investigation,rock mass structural plane investigation,determination of ore-bearing rock point load strength and stability of rock mass classification,the two mining ore body is moderate stability of surrounding rock to instability.Theoretical analysis and discrete element numerical calculation show that the current short-hole shrinkage method is not adapted to the stability of surrounding rock and is the main cause of the ore dilution loss.In order to adapt to the stability of surrounding rock and to protect the earth's surface,may need to change to overhand cut-and-fill stoping method.Therefore,using grey theory with analytic hierarchy process(ahp)mining method optimization model is established,and through the analytic hierarchy process(ahp)to determine weights of the factors affecting mining method selection,and then the optimum selection of mining method by grey incidence decision method.The results of the optimization on the big stage to horizontal layered classification tail sand filling mining method,the stope structure parameters are:phase level 100m,sublevel height 20m,stratification height 5m,ore removal using scraper.By analyzing the mechanism of the upward horizontal slice stoping and backfilling body,the characteristics of dynamic load and trackless equipment operation,with reference to roadbed engineering of roadbed,the design principle of analysis of strength of filling body model is established.According to the calculation results,recommend cementation layer thickness of 0.4m,7 days of filling body strength 1.OMpa.Analysis shows that the presented on the big stage to horizontal layered filling method can better adapt to the two mining ore body conditions and it can also obtain good recovery index and environmental effect.