Xiaoyi Bauxite China Goaf Ore Body Safe And Efficient Mining Technology Research

A large number of civil mined-out areas exsit in the mining stops for the complex surrounding environments of bauxite mine in China, not only bring about serious damages to primary ore structure, but also pose a great threat to safety production of bauxite mine.In order to seek maximum profit and reduce cost of predatory exploitation, the rich resources are exploited while the poor are abandoned and the irregular pillars and roofs are left,waste rock and lean ore were discarded everywhere in the mined-out areas,which brings in high loss and dilution rate.In all five diggings of Xiaoyi Aluminum Mine,there are a quantity of mined-out areas. Large scale equipments often fall into these areas in the production process, causing damages to equipments and casualties to working staffs, which brings in great security risks to safety production. Thereby,studying on the safety mining technology of civil-mined-out areas to increase the recovery rate and decrease the dilution rate shows high economic value and social benefit.Based on comprehensive analysis of literature and information both home and abroad, it studies on the mining technology of Xiaoyi Aluminum Mine of Shanxi Branch China Aluminium Company, and brings foword safety and highly-efficient mining technology to remove mining risks and realize comprehensive recovery and utilization of bauxite resource,by field investigation,academic research, simulation mining and testing mining.The main results are as follows:(1) Based on Reissner thick plates theory,the cirtical thickness of roof in limestone, shale,bauxite and sandstone mined-out areas under self-weight, ground overloading,equivalent moving loads and combined action of self-weight and equivalent moving loads are ananlyzed, with spans are 14.9m,18.7m and 21.9m and the safety factor is 1.0 and 1.3 respectively.(2) Relying on three dimensional numerical analysis, relation between stress and span at key position such as roof and pillar is studied in sedimentary Bauxite mine, distribution characteristics of maximum principal strain and stress are pointed out, providing guidence to safety production of Xiaoyi Aluminum Mine.(3) Mining technology and parameter in large civil mined-out areas are optimized, technical guide and standard of highly-efficient mining are brought forward. By testing mining,23788t high-grade bauxite are recovered, practical recovery rate and dilution rate reaches 92.7% and 6.5% respectively, recovery rate is above 3.06% than previous technology.This technology as the chief safety and highly-efficient mining method, has been popularized in Xiaoyi Aluminum Mine. Problems such as high loss rate, high dilution rate and safety production are successfully solved, as well as good economical and social effects are obtained.