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Using the well-known laws of the theory of elasticity and the basic principles of the quasi-static wave hypothesis of the mechanism of destruction of a solid medium by an explosion, methods have been developed for calculating the parameters of drilling and blasting (D&B) for raises advance using the methods of blast-hole and borehole charges. It has been established that the calculating D&B parameters is carried out in the same sequence as when drifting operation. To check the calculating D&B parameters using the new method during raise advance, a numerical simulation of changes in the stress-strain state of a rock mass under the influence of an explosion was carried out. According to the results of numerical simulation, the formation of zones of inelastic deformation in the face of a rising mine working under blast load, uniform grinding of the rock was obtained, which will avoid the release of oversized pieces after the explosion. The developed methodology was tested in the conditions of the “Yuvileina” mine of PJSC “Sukha Balka” during the raise advance of a 1420 m level using a sticked emulsion explosive (EE) Anemix P. Test explosions obtained good results in blasting the face of a raise, uniform crushing of the rock and a high coefficient of use of bore-holes has been established.

The article provides a comprehensive analysis of using TNT-free explosives (E) in the iron ore mining sector in Ukraine. It delves into the development and application of a specific type of emulsion explosive known as "Ukrainit," which is free from TNT, with the objective of its adoption in underground iron ore mining operations. Pilot blasting activities were carried out at PJSC "Zaporizhzhia Iron Ore Plant" (PJSC "ZIOP"), selected for its state-of-the-art equipment and advanced ore extraction technology. Through examination of ground-level concentrations of environmentally hazardous substances, the study revealed that the highest levels of carbon monoxide, nitrogen oxide, and dioxide were observed in 2008 when underground mining operations exclusively used 100% TNT-containing E. However, by the year 2020, a situation changed with implementation of a blend comprising 78% "Ukrainit" type EE and 22% TNT-containing explosives, resulting in a notable decrease in the maximum concentrations of environmentally hazardous substances compared to 2008. Specifically, carbon monoxide level decreased by 5.0-5.5 times, while nitrogen oxide and dioxide levels decreased by 1.2-1.3 times. Furthermore, use of "Ukrainit" type EE at PJSC "ZIOP" led to a 1.5 times decrease in the environmental hazard index on average (reduced to 36%) compared to the usage of TNTcontaining E. These findings underscore the significant environmental benefits associated with the adoption of TNT-free explosives in iron ore mining operations, particularly in mitigating the release of harmful substances and reducing environmental risks. [ABSTRACT FROM AUTHOR]

The paper represents the analysis, which has helped to determine tendencies of the formation of energy resource complex based on the available mining facilities. The approach helps prolong operating life of the mine with the depleted balance reserves or the one being under abandonment. The proposed technologies of generator gas production by anaerobic digestion of organic raw material in the methane-tanks as well as other approaches to the combined formation of new energy systems make it possible to reorient the mine operation. The approach is extremely important for rather depressed mining regions as it helps solve the problem of social strain. Formation of the joint power and chemical production allows both improving economic expediency and preventing negative ecologic impact on surface and underground mine environment. The proposed tendencies make it possible to outline further issues to be highlighted in the following authors’ studies.

Mathematical modelling of rock mass breaking using blasting has been applied to obtain formulas for the calculation of crush zone radii, intensive fragmentation, and crack formation around the charging cavity in the structure, diameter of the charging cavity, diameter of the charge itself, detonation characteristics of an explosive, boundaries of the rock strength, rock mass jointing, and mineral compression under the effect of rock pressure. The methods have been developed to calculate parameters of drilling and blasting operations (DBOs) while driving the mine workings based upon the idea of the arrangement of blastholes in terms of areas they occupy in a fore-breast as well as upon their location relative to break-off outline. Stage one of the methods involves calculating and designing burn cuts where a distance between blastholes is determined with the help of a fragmentation zone radius. Stage two means calculation of both specific and total explosion consumption per borehole bottom, line of least resistance (LLR) for a borehole in terms of intensive fragmentation, areas of borehole groups, borehole number, analytical and actual distance between boreholes, actual charge amount per borehole, and actual specific and the total explosive (E) consumption per borehole bottom. The methods have been tested in the operating ore mine while driving a mine working. Emulsion explosive (EE) Ukrayinit-PP-2 has been applied. The developed methods have been used to calculate DBOs parameters for the explosive. Trial blasts demonstrated the good firing of a borehole bottom and uniform ore fragmentation; a high coefficient of borehole use has been supported. [ABSTRACT FROM AUTHOR]

The analysis has been made of the technical parameters of the existing passport for drilling and blasting operations (DBO) in terms of compliance with labour safety requirements and scientific-technical standards. The methodology for constructing the DBO passport has been developed, which takes into account the areas of blast-hole groups and the properties of emulsion explosives. The type of the cut has been analysed, modelled and accepted for use, which corresponds to the conditions of tunnelling as much as possible. The zones of deformation and fracturing in the massif around blast-hole charges have been simulated. The level of decrease in the hazard index for atmospheric air has been set when using the emulsion explosive Ukrainit-PP instead of TNT-containing charge – Ammonite No.6 ZhV.

The perspective of discovery of zonal disintegration phenomenon of rocks around underground mine workings is analyzed. The methodological stages for research of this phenomenon are shown. The physics of zonal disintegration of rocks around underground mine workings is disclosed. There are described the possibilities of advanced entropy method and developed energy method that allow to investigate a phenomenon of zonal capsulation of underground mine workings. The sequence of research of this phenomenon parameters is presented. The order of choice of stable shape and resource-saving support in underground mine workings is substantiated, for the deep horizons of the Kryvorizkyi Iron-Ore Basin mines. The method of parameters calculation of self-regulating roof-bolting in underground mine workings is substantiated, which allows to use the rock pressure energy. The design of a self-regulating roof-bolting is developed, which allows applying metal, polymer and rope bolts. The economic efficiency of rock pressure energy usage is substantiated in case of support setting at great depths in underground mine workings.

Laboratory and industrial studies have established the total impact of environmentally hazardous substances, taking into account the distance from the source of emissions and the specific consumption of explosives. With the help of physicochemical analysis and biological testing, the dependence of the change in the conditional indicator of damage to bioindicators with an increase in the distance from the source of emission and the specific annual consumption of explosives was revealed. A methodology for calculating the environmental assessment of the state of atmospheric air around the mine ventilation shaft has been developed. The exponential dependence of the influence of surface concentrations of environmentally hazardous substances on the damage of bioindicators at the cellular and organismic levels has been established, which makes it possible to assess the state of atmospheric air at industrial sites of iron ore mines. The proposed technology of sand drilling, which involves the use of emulsion explosives in mining ore deposits in chamber development systems will reduce emissions of environmentally hazardous substances into the atmosphere and increase the level of environmental safety of iron ore mines. [ABSTRACT FROM AUTHOR]