The problem of increasing efficiency of the underground mining of low-powered low dipping ore bodies is considered in the article. The need to ensure comfortable and safe working conditions for miners requires using engineering solutions for ensuring quality of the ore being mined in the conditions of the congested worked out space.
The effectiveness is substantiated concerning the selective mining of the reserves with blasting of the mine working soil while maintaining the quality of the mined ores. For this through an industrial experiment at the field in the Northern Kazakhstan the studies were conducted that included the methods of mathematical statistics in the processing of empirical material.
The forecasting method was developed concerning evaluation of ore quality that allows to quickly obtain the information. The model for the output of tailings of ore sorting at the ore monitoring station is formulated. The regularity of the distribution of metal content and ore body power in the experimental blocks is revealed. The nomogram of a predictive estimate of the yield of sorting tailings during mining of ore bodies by means of the longwall mining system is proposed. An example of forecasting tailings yield during mining of the ore body section with specific parameters is given. The technology of block mining by the longwall mining system of the rise working with selective ore mining is detailed. The results of the experimental blocks mining are compared with the predicted indicators of the breaking-out in bulk of these blocks reserves using traditional technology.
It is proved that the selective mining reduces the losses and dilution at a slight decrease in labor productivity. Selective mining of blocks is more economically feasible than the complete mining, and the additional labor cost required to break down empty rocks while expanding the working excavation is lower in terms of money than the profit from the additionally obtained metal.