Study On Economic Mining Of Pillarless Sublevel Caving Method

The steady development of domestic mining enterprises depends on the stable ore market price.Since 2014,with the continued expansion of the four major international mines,iron ore market prices continue to fall,resulting in many domestic large and medium-sized mining enterprises a loss,it is necessary to carry out economic research on domestic mines to improve the international competitiveness of domestic mining enterprises.Different mining methods correspond to different production cost structures.In this paper,the economic research of pillarless sublevel caving method is carried out,and the following research work is mainly carried out with Chengchao Iron Mine as the object of application.Firstly,considering the raw ore grade,beneficiation recovery rate,concentrate grade,comprehensive tax rate,concentrate production costs,the cost of the period,the ore production and the ore market price and other factors,the mathematical model of unit ore production cost limit is established.Secondly,the production sections of pillarless sublevel caving method is divided into eight main production sections: excavation,explosion,shoveling,transportation,crushing,lifting,ventilation and drainage.Activity Based Costing is used to allocate the manufacturing cost of the ore production cost reasonably.The cost of ore production is expressed as the sum of the cost of each section.Thirdly,the direct expenditure and the operating cost items are taken as the horizontal cost items,and the cost items of each section are taken as the vertical cost items.The gray correlation analysis method is used to calculate the gray correlation degree between the horizontal cost items and the total cost of the ore production,and the gray correlation degree between the vertical cost item and the total cost of the ore production respectively.Gray correlation matrix is obtained by adding the horizontal and vertical gray correlation degrees.Fourthly,according to the present situation of Chengchao Iron Mine,the 6 kinds of structural parameters of pillarless caving method under the same ore reserves are designed.The ore recovery and dilution rate of 6 kinds of stope parameters were calculated by PFC numerical simulation.The factors such as ore recovery rate and dilution rate are considered,the profit calculation model is constructed,and the final mining profit of the 6 kinds of stope structural parameters model is calculated respectively.The results of this paper show that the production cost limit of unit ore can help mine enterprises to judge profit and loss.Chengchao Iron Mine show a loss in November 2015.Activity Based Costing instead of the traditional cost accounting method can more fully reflect the ore production cost information.Gray correlation matrix can help enterprises find the reasons of the cost of a large change in time,and help enterprises to better manage the cost.The stope structure of the best economic benefit in-430?-500 m stage of Chengchao Iron Mine is that the segment height is 23.3m and the road spacing is 25m.