• Energy Research

Based on both theoretical and practical experiences, the measures aimed at controlling emergency shutdowns of stopes have been highlighted. These stopes are connected with the emergency rigid settlements of powered complexes. In terms of the Western Donbas mines, there are certain risks of a shutdown of stopping operations within the zone of primary roof caving. Thus, the causes of emergency rigid settlements of the support may include the following: layers of the main roof rocks are hanging and not timely delaminated; sudden changes in lithology; hydraulic overloading of the main roof; structural flaws of support under certain conditions of its use, etc. In this paper, the theoretical method of scientific cognition was applied, which, with its help, makes it possible to switch from single low-efficiency measures to a set of actions aimed at preventing any uncontrolled situation. Obtaining certain generalized knowledge means obtaining a much deeper representation of reality, penetrating into its essence. The study also involves statistical analysis, being the basis for outlining a zone of primary caving where a high degree of risk is observed. Certainly, the generalization of these measures does not solve the problem completely. Consequently, there will be further attempts to search for and achieve principal new solutions in the future.

Based on both theoretical and practical experiences, the measures aimed at controlling emergency shutdowns of stopes have been highlighted. These stopes are connected with the emergency rigid settlements of powered complexes. In terms of the Western Donbas mines, there are certain risks of a shutdown of stopping operations within the zone of primary roof caving. Thus, the causes of emergency rigid settlements of the support may include the following: layers of the main roof rocks are hanging and not timely delaminated; sudden changes in lithology; hydraulic overloading of the main roof; structural flaws of support under certain conditions of its use, etc. In this paper, the theoretical method of scientific cognition was applied, which, with its help, makes it possible to switch from single low-efficiency measures to a set of actions aimed at preventing any uncontrolled situation. Obtaining certain generalized knowledge means obtaining a much deeper representation of reality, penetrating into its essence. The study also involves statistical analysis, being the basis for outlining a zone of primary caving where a high degree of risk is observed. Certainly, the generalization of these measures does not solve the problem completely. Consequently, there will be further attempts to search for and achieve principal new solutions in the future.

Abstract A study of gas flow through porous coals is significantly important for the accurate assessment of the state of endogenous fire risk. Coal characterizes of a unique pore structure which provides a good storage capacity and an ideal transport pathway for the movement of gases. Gaseous products released from the source of coal self-heating flow through coal and may be subject to adsorption. In this study, the effects of the transport of multi-component gas mixture through a sorption column filled with granular coal and inert material were investigated. The experiment with coal presented in the paper proved that gas concentrations at the inlet (Co) and at the outlet of the sorption column (Ck) varied depending on the properties of coal and gas molecules. Based on the results, an index demonstrating the relationship between these concentrations was calculated. The experiment of gas mixture flow through inert material confirmed that the lowest index, i.e. below 0.7, obtained for propylene and acetylene in the experiment with coal was a result of sorption processes. Gases with lowest critical temperatures, such as carbon monoxide and hydrogen had the highest index which was above 0.9.

Abstract A study of gas flow through porous coals is significantly important for the accurate assessment of the state of endogenous fire risk. Coal characterizes of a unique pore structure which provides a good storage capacity and an ideal transport pathway for the movement of gases. Gaseous products released from the source of coal self-heating flow through coal and may be subject to adsorption. In this study, the effects of the transport of multi-component gas mixture through a sorption column filled with granular coal and inert material were investigated. The experiment with coal presented in the paper proved that gas concentrations at the inlet (Co) and at the outlet of the sorption column (Ck) varied depending on the properties of coal and gas molecules. Based on the results, an index demonstrating the relationship between these concentrations was calculated. The experiment of gas mixture flow through inert material confirmed that the lowest index, i.e. below 0.7, obtained for propylene and acetylene in the experiment with coal was a result of sorption processes. Gases with lowest critical temperatures, such as carbon monoxide and hydrogen had the highest index which was above 0.9.

Global warming increases the risk of power outages. Mine water pumping stations pump approximately 100 million m3 of water per year (2023). The cessation of mine water pumping would expose neighboring mines and lower lying areas to flooding. The pumping stations have some containment, but a prolonged shutdown could cause environmental problems. Remediation of the resulting damage would be costly and time-consuming. The combination of the problems of dewatering abandoned mines and storing energy in the form of hydrogen to ensure continuity of power supply to pumping stations has not been the subject of extensive scientific research. The purpose of this paper was to develop options for protecting mine water pumping stations against the “blackout” phenomenon and to assess their investment relevance. Six technically feasible options for the modernization of mine water pumping stations were designed and analyzed in the study. All pumping station modernization options include storage of the generated energy in the form of green hydrogen. For Q1 2024 conditions, the option with the partial retail sale of the produced hydrogen and the increased volume of produced water for treatment is recommended for implementation.

Global warming increases the risk of power outages. Mine water pumping stations pump approximately 100 million m3 of water per year (2023). The cessation of mine water pumping would expose neighboring mines and lower lying areas to flooding. The pumping stations have some containment, but a prolonged shutdown could cause environmental problems. Remediation of the resulting damage would be costly and time-consuming. The combination of the problems of dewatering abandoned mines and storing energy in the form of hydrogen to ensure continuity of power supply to pumping stations has not been the subject of extensive scientific research. The purpose of this paper was to develop options for protecting mine water pumping stations against the “blackout” phenomenon and to assess their investment relevance. Six technically feasible options for the modernization of mine water pumping stations were designed and analyzed in the study. All pumping station modernization options include storage of the generated energy in the form of green hydrogen. For Q1 2024 conditions, the option with the partial retail sale of the produced hydrogen and the increased volume of produced water for treatment is recommended for implementation.

AbstractThe hydro-mining technology is considered as a promising method of bituminous coal excavation. The paper presents the results of the in-situ experimental campaign and modelling of hydro-cutting technology application. The proposed innovative technology was tested in terms of the effects of the distance between the outlet of water from the nozzle and a sidewall, pressure of the water jet, as well as the type of a nozzle on hydro-mining effectiveness. The hydro-cutting tests of coal seam performed in the Experimental Mine “Barbara” in Poland proved that the increase in water pressure in the range 20–40 MPa only slightly affects the coal face structure, while high pressure, of 80–100 MPa, has a significant impact on a coal face structure. The experimental results also showed the major effects of operating time as well as the distance of the water jet on the effectiveness of coal face mining.

AbstractThe hydro-mining technology is considered as a promising method of bituminous coal excavation. The paper presents the results of the in-situ experimental campaign and modelling of hydro-cutting technology application. The proposed innovative technology was tested in terms of the effects of the distance between the outlet of water from the nozzle and a sidewall, pressure of the water jet, as well as the type of a nozzle on hydro-mining effectiveness. The hydro-cutting tests of coal seam performed in the Experimental Mine “Barbara” in Poland proved that the increase in water pressure in the range 20–40 MPa only slightly affects the coal face structure, while high pressure, of 80–100 MPa, has a significant impact on a coal face structure. The experimental results also showed the major effects of operating time as well as the distance of the water jet on the effectiveness of coal face mining.