Development of resource-saving mining method for stoping of various grades of rich iron ores

Purpose. Research and development of resource-saving development of resource-saving mining method for stoping of various grades of rich iron ores using borehole hydraulic technology during the formation of a underground quarry and the breaking of the main stock of the panel onto it using the drilling and blasting, which will ensure an increase in the quality of the extracted ore raw materials, safety, environmental friendliness and technical and economic indicators of the efficiency of mining operations in complex engineering and geological conditions. Methodology. A comprehensive research method was used, which includes: analysis of mining-geological and mining-technical conditions of occurrence and characteristics of rich martite ore deposits in the fields of Kryvbas mines; constructive and functional analysis of the mining method of stoping of rich iron ores; generalization of the theory and practice of development of complex-structured iron ore deposits using borehole hydrotechnology at deep horizons; geomechanical simulation of the stress-strain state of the ore-rock mass in the zone of stoping using the finite element method; design of a scheme for cleaning extraction of different grades of iron ores using borehole hydrotechnology; technical and economic assessment of the developed resource-saving mining method of stoping. Results. A resource-saving mining method for stoping of various grades of iron ores using borehole hydraulic technology has been developed and economically substantiated, which allows: increasing labor productivity in all mining processes due to the use of self-propelled equipment and high-performance jet-monitor method breaking during the formation of a underground quarry during most mining operations; reducing the volume of temporary workings due to the exclusion of driving cut-out raises; organizing selective flows of ore of different quality and separately waste rock; extracting a larger volume of clean ore, creating large areas of outcrops of underground quarrys, due to the use of borehole hydraulic technology in the process of forming a underground quarry (development of the richest part of the deposits located in their central part). Scientific Novelty. It has been established that in the conditions of development of deep horizons of iron ore mines, rational technological parameters of the processes of geotechnology of stoping are determined by geomechanical conditions and complexes of applied geotechnics. Dependencies of transformation of stress-strain state around underground quarrys formed by the hydromonitor method have been further developed. Practical Implication. The practical development, during the development of various ore deposits in complex geomechanical conditions of deep horizons of Krivbas mines, of borehole hydrotechnology for the stoping of rich iron ores, without dilution and with an increase in their quality, as well as without enrichment, will make it possible to obtain a new type of raw material – iron ore superconcentrate, and will allow achieving an economic effect of about 64.4%. Keywords: rich iron ores, extraction rates, stoping, stress-strain state, borehole hydrotechnology, iron ore superconcentrate, numerical simulation.