Study On The Combined Mining Technology Of Multilayer Adjacent Gently Inclined Orebody With Thin-medium Thickness

Abstract:The Guzhang yantouzhai is rich in vanadium mineral resource and the main useful minerals are high grade and good quality. Howerver, the mine ore body condition is extremely complex, multilayer composite is presented with the gently inclined thin-medium thickness orebody and mezzanine, and also the mezzanine thickness is close to seam thickness, which belongs to typical complexity of difficult mining body. In order to achieve the safe and efficient recovery of mine resources and improve resource utilization, on the basis of the analysis of the mining conditions, the paper firstly determine the commingled and sub-mining definition indicators of the mine mezzanine orebody by theoretical calculations. Then the limit exposed area of the stope is analyzed with the methods of numerical simulation and theoretical calculation.Acorrding to the analysis, two non-traditional mining plans are proposed and the optimization process is conducted. Finally, the monomer design is put forward for selected mining plan. The paper mainly achieves the following research results and conclusions:(1) By analyzing the yantouzhai vanadium mine geological reports, the author has mastered the mine stratigraphy, structure situation and geological characteristics, which can provide the basic information and data for carrying out numerical simulations and theoretical analysis and reasonablely designing mining plan of the gently inclined thin and thick orebodies and mezzanine.(2) Taking industrial grade as evaluation criteria, the paper has deduced the formula of reasonable stone removed thickness with submining sandwich orebody and the calculated results also show that the commingled method is not suited to the yantouzhai vanadium mine.(3) The stope limit exposure area is calculated and analysized respectively with MIDAS/GTS numerical simulation software and Mathews method by applying rock strength criterion and allowable limit displacement criterion synthetically as the underground stope engineering failure criterion. The comprehensive results show that, the stope limit exposure area is700m2when the arrangement of stope is horizontal and the stope limit exposure area is660m2when the arrangement of stope is gradient.(4) on the basis of above analysis results, two non-traditional mining methods, namly, commingled method and sub-mining method, are primarily choosed. By the technical and economic comparison comparison, the mechanized combined sub-mining on the level layering method wiht high degree of mechanization, flexibility and easy to implement is finally selected and then a detailed program design is carried out.