Application Range Research On Semi-continuous Mining System In Large Open-Pit Coal Mines

Through investigation, theoretical analysis and in-situ engineering practice, this paperconducts a deep investigation into the confirmation of large tonnage truck’s economichauling distance, starting point hauling distance of semi-continuous mining system andscale economies of applied semi-continuous mining system of surface mine, starting withthe study of applied range of semi-continuous mining system of large surface coal mine inChina by adopting the principle of surface mining, methods of mining system engineering,technological economics, computer technology as well as other methods..Based on the previous research results, this paper uses the approach of grey correlationtheory to analyze the amount of factors that affect the production cost of surface mines.Thus, by finding out the main influential factor, the cost reduction of the surface mine mayoccur, meanwhile, this also provides a reference for elevating the economic benefit ofsurface mines. In the meantime, this paper invites an oil price variation coefficient K toanalyze the influence towards the truck’s proper hauling distance giventhe fluctuationof theoil price. Through this process, a proper hauling distance changing trend is get which alsoprovide a certain technical basis and reference.By establishing a calculation model of material hauling distance, this paper takes aclose look at the factors that affect material hauling distance under the approach ofsemi-continuous mining system. Meanwhile, this paper makes a comparison betweendiscontinuous mining system and semi-continuous mining system by modeling the haulagecost. Through case studies, this paper compared the starting point hauling distance whengiven a fixed annual output and an unfixed mining depth with a fixed mining depth but anunfixed annual output. Through cost analysis, this paper confirms the production scale ofapplied semi-continuous mining system when mining depth is fixed. The oil price variationcoefficient K is invited to analyze the effect on the production cost of surface mine when theannual output and mining depth is fixed but the oil price is unfixed. Thus, the cost riskswhich brought by oil price fluctuation can be reduced.Based on the cost analysis of surface mine, the boundary conditions of establishmentand application of overburden semi-continuous mining system are systematically analyzed.The paper suggests that the construction condition is to determine the boundary haulingdistance under the assuming production capacity by adopting the method ofsemi-continuous mining system instead of single-shovel-truck discontinuous mining system.The application condition（hauling distance is fixed） is to determine the systematic profit,operation and system abolished boundary output scale. Meanwhile, for the applied condition of continuous mining system of bucket wheel excavator of surface mines in China, weanalyze this special case of transforming the continuous mining system into thesemi-continuous mining system as well as bring up the systematic transformation schemes,pros and cons, and the conditions of boundary production scale.Through case studies, this paper testifies the practicability o f the models mentionedabove and the research results have positive meanings for enriching the semi-continuousmining system theory and building a large, efficient, low carbon surface mine.