Theory And Method Of Selected Mining Multiple Coal Seam In Open Pit

The thesis is based on the needs of compound seems selective mining of indomestic open pit coal mines, the studied methods involve basic theories of surfacemining, mining system engineering theories,computer technology and economicevaluation, and so on. Based on field investigations, case study and theoreticalanalysis; the influence factors of selective mining and the ways to improve theselective mining efficiency were studied in this thesis. There are four aspects canimprove selective mining efficiency including selective mining technology, miningprocedure, mining parameters and blasting method.Based on the coal resources deposit occurrence and characteristics of our countryopen pit mines, the selective mining is divided into four types, including thin seemsselective mining, thick parting layer seems selective mining, thin parting layer seemsselective mining and coal and rock mixed layer. The thesis analysis of the factorsaffecting the need and feasibility for selective mining, and effective composition ofcompound seems selective mining, proposed evolution of selective mining result. Thepaper analyzes the typical production technology of China's open pits for the selectivemining and the effects of selected mining, involved single Bucket-truck system, andBucket wheel excavator continuous mining technology, and surface miner miningtechnology. Proposed compound seems selective mining technology and equipmentselection principles and the thickness of the selected mining method. Establishedcompound seems selective mining decision model. According to the layer depositsmining characteristics, through the single-bench mining model, the thesis analysis ofthe typical ways to advance during the mining in open pit on the impact of theselective mining index such as refuse rate and loss rate. To maximize the benefits ofopen pits, the thesis established the minimum coal seam thickness optimization modelwithin bench; the results show that the mining produce has influence on the benefitsof resources development and selective mining index. On the target of the maximumrecovery coal reserves and the minimum refuse coal reserves, Using graph theorymethods to optimize compound seams selective layered combinations, by the way ofgeometric modeling and mathematical modeling, the thesis obtained the relationsbetween the selective mining performance index such as loss rate, dilution rate, theminimum thickness of the selective mining, the gangue minimum removed thickness of coal and the bench height, cut width. Proposed ways to working face parameters tooptimize the effect of selective miningFrom the perspective of method of loose blasting in open pit and optimization ofblasting parameters, this paper makes classification of conditions of selectedmining and put forward pertinent blasting method. The feasibility of using tightblasting to improve effects of Selected mining is analyzed; drilling method ofimproving recovery rate and reducing loss rate and optimum structural design methodof charge are put forward in conditions of separate blasting and mining of rock andore, mixed blasting and separate mining of rock and ore and mixed blasting andmining of rock and ore. The practicability of the study result is verified with severalopen pit examples in this paper. This study result has positive significance inenriching our country·s theory and technology of compound seam and building openpit with large-scale, efficient and low-carbon.There are36figures,21tables and150references in the thesis.