Irkutsk school of mining engineers is celebrating 90th anniversary

It is in 1930 that the training of mining engineers began in Eastern Siberia on the basis of the Siberian Mining Institute (now Irkutsk National Research Technical University). In 1931 the Department of Mining Arts was organized, which later was named the Department of Mineral Deposits Development. Over the years, the Department has trained more than 7000 graduates – mining engineers, who made a huge contribution in the development of the mining industry in the Irkutsk region and neighboring territories including Mongolia. The Department has trained more than a hundred mining engineers and Masters of science for Mongolia; assisted the lecturers and professors of the Mongolian Polytechnic University (now Mongolian University of Science and Technology) in organizing the educational process for training specialists for the country's mining industry. At its different formation stages the Department of Mineral Deposits Development was headed by well-known scientists – mining engineers, who created three scientific schools for the development of coal, placer and gold deposits; the obtained scientific results were marked with two State awards of the Russian Federation, dozens of doctoral and candidate dissertations were defended and about 100 patents were received. Today, the Department super- vises the training of mining engineers in open-pit and underground mining of mineral deposits, carries out a large amount of research and design work on the orders from mining enterprises, trains academic staff, develops new technologies and technical solutions in order to improve mining operations. The Department is deeply involved in the cooperation with mining enterprises, research and design organizations, as well as with universities that train mining engineers.

APPLICATION OF HUMATIC REAGENT FOR DUST DESTRUCTION AND DEGASATION IN MASS EXPLOSIONS

The work is devoted to the coverage of the results of research and industrial tests of environmental efficiency of water replacement in internal and external hydraulic wells in the quarries of mining enterprises for humic reagent [1]. Scientific and technical problem of determining environmental efficiency, solved by conducting in 2020 by the Research Mining Institute (NDGRI KNU) industrial research in the conditions of PJSC "Northern Mining and Processing Plant" (PJSC "PIVNGZK", Kryvyi Rih) kg / dust3 kg rocks) and gas formation (kg / kg BP) during mass explosions with the use of water in the holes in comparison with the use of humic reagent. Dust- binding and degassing properties of humate-based reagents are confirmed by the results of research and industrial tests conducted by the Research Institute of Occupational Safety and Ecology in the Mining and Metallurgical Industry (NDIBPG KNU) in 2019 by conducting experiments with pre-wetting blocks before conditions of quarries of Inguletskyi, Central and Northern GZK [1]. According to the results of experimental and industrial tests, it is substantiated that the efficiency of the use of humic reagent in the external water hammer in comparison with the use of technical water was: dust suppression increases by 20.0%; neutralization of carbon monoxide - 59.4%; neutralization of nitrogen oxides - 55.1%.

Experimental and CFD Simulations of the Aerosol Flow in the Air Ventilating the Underground Excavation in Terms of SARS-CoV-2 Transmission

The paper presents the results of experimental and model tests of transport of dispersed fluid droplets forming a cloud of aerosol in a stream of air ventilating a selected section of the underground excavation. The excavation selected for testing is part of the ventilation network of the Experimental Mine Barbara of the Central Mining Institute. For given environmental conditions, such as temperature, pressure, relative humidity, and velocity of air, the distribution of aerosol droplet changes in the mixture of air and water vapor along the excavation at a distance was measured at 10 m, 25 m, and 50 m from the source of its emission. The source of aerosol emission in the excavation space was a water nozzle that was located 25 m from the inlet (inlet) of the excavation. The obtained results of in situ tests were related to the results of numerical calculations using computational fluid dynamics (CFD). Numerical calculations were performed using Ansys-Fluent and Ansys-CFX software. The dimensions and geometry of the excavation under investigation are presented. The authors describe the adopted assumptions and conditions for the numerical model and discuss the results of the numerical solution.

LOCALIZATION OF EXPLOSION PULSES IN A CLOSED SPACE IN COAL MINES

The data on the prospect of using an artificial high pressure water barrier as a method of localizing the explosion impulse in the confined space of tunnels and mines are presented. The explosion impulse and the process of its decay in interaction with water fog have been studied. In the course of field research, an explosion was simulated in the shock installation, and a method for its localization was developed using four water screens (barriers). The water screen was created using a system of ring-shaped water distribution headers with high pressure nozzles installed in a circle. Hexogen was used as an explosive. Experiments on localization of explosions were carried out on the base of the "Grigol Tsulukidze Mining Institute of Georgia" in Tbilisi, Georgia, together with the research group of the Faculty of Chemistry and Chemical Technology of al Farabi Kazakh National University and the Institute of Combustion Problems. The influence of the water barrier on the process of shock wave attenuation at 3 points of overvoltage of the section is established. The test results showed that the average values of the overpressure in the three sections were reduced by 38.8%, 26.67% and 19.2%, respectively. The action of the shock wave occurs according to an exponential function, and all other wave changes along any other trajectory on the plane of h – t change are described by a single time dependence.

Challenges and Opportunities for End-of-Life Coal Mine Sites: Black-to-Green Energy Approach

This paper presents the possibilities of adapting active mines to generate green energy after their closure using their resources and/or infrastructure. For this purpose, firstly, the temporal horizon of selected mines in Poland was determined, its basic assumption being the analysis of the current state. In the research, 18 mining plants operating within 12 mines in the Upper Silesian Coal Basin (USCB) were analyzed. The analyzed mines belong to three of the five largest hard coal producers in Poland, and the main object of exploitation is hard coal of energy types. Severe restrictions or even abandonment of further investments in the development of the coal mining industry were taken into consideration (regarding the construction of new shafts or the development of new exploitation levels). When determining the temporal horizon, the challenges that hamper the exploitation based at the levels of natural hazards and depth of exploitation in each mine were considered. Secondly, the criteria for the adaptation of active mines to generate energy are presented. The possibility of using the resources and infrastructural potential of active mines to produce geothermal energy from water, extracting coalbed methane (CBM), and processes of underground coal gasification (UCG) are analyzed. Finally, for a selected example—generating energy from underground coal gasification in Polish mine conditions—a structural analysis of the criteria was performed using the MICMAC method, as the Central Mining Institute has an extensive experience in the development of underground coal gasification trials in coal mines. Based on expert analysis and using structural analysis, the criteria important for UCG were selected. As demonstrated in the article, the MICMAC method can be applied in other scenarios with different criteria to implement new technologies in coal mines.

Technological investigations of alluvial garnet sands from the Kola Peninsula

The paper presents the investigation results on two technological samples of alluvial garnet sands from Yavr area located in the southwest of the Kola Peninsula. The first sample TP-11/2 (mass 250 kg) was used to study the granulometric, mineralogical and chemical composition of garnet sands. The second sample TP-12 (mass about 6.5 ton) was used to manufacture some garnet concentrates for the waterjet cutting testing. It has been established that the main material of TP-11/2 sample is concentrated in the size of -0.63 + 0.10 mm. The larger particles make 5.0%, the smaller particles make 7.0%. The size distribution in the TP-12 sample is similar. The main minerals of the sands are quartz, feldspar, garnet, amphiboles, pyroxenes, mica, rutile and ilmenite. The percentage of secondary minerals represented by sillimanite, kyanite, apatite, tourmaline, graphite, magnetite, and single zircon grains is less than 2%. Garnet in Javr area sands is 9–-97% in the free phase. The mass concentration of garnet in the sands is 15–19%, the mass concentration of rutile is 1.0%. Garnet corresponds to almandine in composition. A small part of garnets (about 15–20%) contains a pyrope component. The prevailing shape of garnet grains is angular; the profile of the grains is predominantly isometric and elongated. The garnet sands were dressed at the pilot concentration plant of the Mining Institute, in the gravitymagnetic-electric circuit using the following equipment: a fine screen, a spiral sluice, a concentration table, a weak field magnetic separator, a high-intensity magnetic separator, an electrostatic separator for scavenging of rough garnet concentrates. According to the test results, all garnet concentrates with the size of –0.63 + 0.315 mm, –0.315 + 0.18 mm, –0.18 + 0.10 mm were assumed suitable for the waterjet cutting.

Silver 50 kopecks coins made by the metallurgist and the Mining Institute graduate Petr Latyshev

This paper continues a series of publications on the history of Russian silver 1 Rouble coins and the contribution of the Saint Petersburg münzmeisters, who graduated from the Mining University, to the coin business. The study focused on silver 50 Kopecks coins of the 1922–1924ss made by the former münzmeister of the Saint Petersburg Mint Petr Latyshev, who graduated from the Mining School. A study of archives confirmed his involvement in the minting of the first silver coins issued by the Soviet State in the 1920s at both the Leningrad Mint and the London Mint. The authors examined silver 50 Kopecks coins of the 1922–1925ss and established certain features of their production. By means of modern technology, the authors examined the distribution of chemical elements across the surface and defined the structure of the silver matrix. A relationship was established between certain elements and the hardness of different areas of the coin. All experiments were conducted using state-of-the-art equipment of specialized laboratories at the Saint Petersburg Mining University. The new approach to the study of historic artefacts enables to get a deeper insight into the production technology that was used. Vickers microhardness tests helped establish that the segregation can be primarily linked to such elements as nickel, copper and lead, which may affect the quality of the final product if their concentration is high. This research study was carried out as part of the preparation research work for the exhibition of the Coin Collection of the Saint Petersburg Mining University’s Museum of Mining, as well as in the framework of the cooperation agreement signed on 29/11/2019 between the Saint Petersburg Mining University and the Museum für Naturkunde at the Leibnitz Institute for Evolution and Biodiversity Science in Berlin, Germany.