The technology for extracting and discharging coal from an underroof seam uses the so-called gravitational extraction method in which coal is extracted and discharged from under the roof by gravity. Here, coal can be discharged onto the main conveyor (face conveyor, located in the supported area), central conveyor (rear conveyor in Western literature), and tail conveyor (discharge conveyor, located in the unsupported area). The most common facilities used currently are longwall sets of equipment providing discharge onto tail conveyors. The purpose of this study is to measure the performance of a motorised plate feeder supplying coal from the outlet port of a roof support to a conveyor during the extraction of thick seams with discharge onto the face conveyor. To achieve the goal, it is proposed to measure the coal volume using machine vision. Methods for calculating a unit volume in a measuring section using a three-dimensional model were investigated. Laboratory studies were carried out to estimate the relative errors of the methods. The research allowed properly defining: a method for collecting data to calculate the unit volume of coal; a method for calculating the unit volume in the measuring section; a method for calculating the feeder performance using machine vision, and approaches for physically simplifying the video scene examined by machine vision. A relative error of less than 10 % with the existing measurement accuracy for constructing a coal layer surface height map indicates the sufficiency of the proposed calculation method for engineering use. The developed mathematical apparatus for calculating the unit volume of coal at the measuring section and measuring the feeder performance allows creating algorithmic software using the elementary mathematical functions of addition, subtraction, multiplication, and division. This aspect is important because it lower sights for the software development environment, and therefore expands the range of hardware suitable for calculating the feeder performance.

The Timan-Pechora oil and gas province remains rather promising for the discovery of new hydrocarbon fields and deposits, including large ones. However, in recent years, the efficiency of oil and gas prospecting and exploration has been rather low. At relatively high exploration maturity of prognostic oil resources (> 50%) and low exploration maturity of gas resources (about 30%), prospecting for new fields and deposits focuses on nonstandard geological conditions of their occurrence. This, in turn, requires the development of new methods and technologies for the development of such resources and the simulation of hydrocarbon systems and specific deposits, reflecting their non-standard occurrence and structure, thereby making prospecting more complicated. Therefore, the determination of rational methodological approaches to prediction, prospecting, and exploration of hydrocarbon deposits represents an urgent scientific and applied task.
A comprehensive analysis of geological and geophysical characteristics of the promising targets based on the data of up-to-date seismic exploration and drilling ensures that complex traps are mapped by geophysical methods and prognostic resources and reserves of discovered deposits are estimated more precisely and confidently. Integration and analysis of geological and geophysical research materials using advanced methods and technologies can significantly expand oil and gas prospects and optimize the prospecting for productive traps and increase exploration efficiency by reducing the risk of unproductive wells.
This paper presents and discusses the options for predicting oil and gas potential and provides recommendations for prospecting hydrocarbon deposits using up-to-date methods and technologies for interpreting geological and geophysical data. The research targets were terrigenous and carbonate natural reservoirs in the northeastern part of the Timan-Pechora oil and gas province, including the shelf of the Pechora Sea, Izhma- Pechora and Khoreiver Basins situated in different structural and tectonic zones. The analysis of extensive geological information has revealed that these areas exhibit all the necessary conditions for the existence of unique geological features and the potential for the discovery of oil and gas deposits therein.

The condition for stable fixation of a collector on the surface of diamonds and their flotation is the use of collectors of the optimal fractional composition and the choice of the optimum temperature regime of the process. To determine the parameters of the diamond flotation regime, the regularities of the phase transitions of asphaltene-tar fractions at increasing temperature and diluting F-5 with technical diesel fraction were established. It was demonstrated that increasing the collector temperature leads to the transfer of asphaltenetar fractions to a dissolved and finely dispersed state. To an even greater extent, dissolving asphaltene-tar fractions is facilitated by the addition of medium- and low-molecular weight fractions of oil, for instance, a technical diesel fraction.
It was revealed that the KM-10, KM-14, and KM-18 reagents, being compounds of F-5 fuel oil with technical diesel fraction (10–18 % DF), were characterized by optimal viscosity and ability to displace aqueous phase from a diamond surface, thus ensuring stable hydrophobization and high floatability of diamonds. The optimal temperature regime has been selected, which involved maintaining the temperature at the stage of conditioning with the collector at +30–40 °С, at which the maximum selective fixation of compound collectors on the diamond surface, characterized by the value of the limiting wetting angle, was achieved. The flotation tests have confirmed that the best results are achieved at a temperature of +30–40 °С at the conditioning stage and +14–24 °С at the flotation stage. At +24 °С, the best results were obtained for the relatively less diluted KM-10 and KM-14 fuel oils obtained by diluting F-5 fuel oil with a technical diesel fraction at the diluent volume fractions of 10 and 14 %. The diamond recovery achieved in the flotation tests was 3.8–4.5 % higher than when using the traditional collector, F-5 fuel oil. At +14 °С, the highly diluted fuel oil, KM-18 with a volume fraction of 18 % of the technical diesel fraction, demonstrated better collecting abilities.
The optimal compositions of the collector and the regimes of feed preparation and flotation were tested at a foam separation unit. The tests showed that it is possible to increase diamond recovery into concentrate by 2.3–4.5 %. The recommendations are provided on the use of thermal conditioning in the foam separation cycle and maintaining the conditioning medium temperature at +30–40 °С and the foam separation temperature at +14–24 °С.

The main source of potassium fertilizers is sylvinite ores consisting primarily of halite (NaCl), silicate and clay-carbonate slurries (clay-salt slurries). Processing of natural potash ores is mainly carried out by the flotation method, which separates KCl, NaCl, and clay-salt slurry. The research is aimed at revealing the effect of sonochemical pretreatment of the depressor reagents, CMC and starch, on dynamic viscosity, aggregate size, electrokinetic potential of these reagent solutions and sylvin flotation performance. It has been established that sonochemical treatment of depressor solutions decreases the size of aggregates of starch molecules by more than 133 times and that of aggregates of CMC molecules from 6 to 4 nm. It has been revealed that sonochemical treatment of anionic CMC solution shifts the electrokinetic potential towards the area of negative values with an increase in acoustic power, while sonochemical treatment of any acoustic power has no effect on the zeta potential of nonionic starch. It has been found that the sonochemical treatment lowers the dynamic viscosity of CMC and starch solutions: the viscosity of CMC solution at a maximum acoustic power of 420 W decreases by 44 % and the viscosity of starch solution at the same acoustic (ultrasonic) power decreases by 70 %. Furthermore, sonochemical pretreatment of sylvin flotation depressors contributes to an increase in KCl recovery and a decrease in the slurry content in the flotation concentrate. The possibility of reducing the consumption of ultrasonic treated depressor is also demonstrated. It is expedient to test the obtained findings in pilot-plant conditions.

The steady trend of complication of mining and geological factors in underground coal mining and at the same time the processes of mining intensification cause growth of dynamic manifestations of natural factors of mining, such as sudden coal and gas outbursts, rock bursts, rock collapses, leading to gas and dust explosions and fires. This requires developing the models of different phenomena manifestation risks, which enable improving the process safety of a mining enterprise. In this study, based on the methodology of aerological risk assessment in coal mines, a structural analysis of aerological risks was carried out. The criteria of hazard of mining-geological and mine engineering factors and vulnerability of schemes and methods of ventilation, ventilation facilities, and main fans were developed. A hierarchical structure of aerological risks of higher ranks was developed. The presented risk structure allows determining the area of superposition of hazards of coal mining and vulnerability of ventilation systems for each mine and its individual facilities, as well as quantifying these areas in the form of aerological risks. The ranges of aerological risk values of higher ranks for super-category mines and mines hazardous by sudden coal and gas outbursts for different ventilation modes were established. The presented methodology enables forecasting and reducing aerological risks in course of designing, operation, liquidation, and conservation of coal mines.

The «National Security Strategy of the Russian Federation until 2030» prioritises the use of resource-saving and waste-free technologies for natural resource extraction and processing, import substitution of mining equipment in the Russian mining sector, and the introduction of digital technologies at all stages of resource extraction and processing in the mining industry to improve their safety. The aim of the article is to study the gradual development of peat machinery classification and the relevance of its improvement through integrated mechanization devices to create waste-free extraction and processing of peat deposits using fullcycle mobile complexes with the development of environmentally friendly and resource-saving technologies for peat production. The methodological basis of the research includes post-event analysis, peat machine design theory, and systems analysis. As a research result, new system factors influencing the development of the classification of currently available machinery and equipment for peat production, as well as classification variants combining the processes of extraction and processing of peat deposit resources are provided, which allow modeling the structure of full-cycle mobile complexes for extraction and processing of peat deposit resources without waste. In terms of practical application, the classification of peat machinery enables the development of a rational decision-making data system for optimizing the structure of the technological machinery and equipment fleet of peat extraction enterprises, taking into account the deteriorating conditions of peat resources and development technologies, the economic conditions of the industry and the current trends of digitalization in the extractive industry.

Under the current conditions, the Russian coal industry is under unprecedented external pressure: it is both the imposed sanctions and the need to meet strict environmental requirements that inevitably lead to the closure of part of the enterprises, the collapse of value chains (VCs) in the coal and related industries. As a result, a complex restructuring of the industry is required. To carry it out successfully, a reliable criterion is needed to assess the prospects for the long-term development of both individual companies and VCs as a whole. From the authors’ point of view, the degree of stress resilience of VCs is the criterion needed.
The article deals with the evaluation of the long-term development prospects of the coal industry based on the established stress resilience of VCs and the related strategies of coal companies’ behavior. The authors proposed an algorithm for assessing the stress resilience of VCs in the coal industry: a description of the aspects and typology of VCs in the Russian coal industry; an assessment of their current stress resilience; a description of the survival strategy of the companies included in the VCs; an assessment of the prospects for sustaining VCs under sanctions. Subsequently, this article presents theresults of the stress resilience assessment of 169 coal companies operating in 110 different VCs between 2010 and 2021.
The authors created a typology of VCs in the coal industry, which makes it possible to identify three basic types of VCs in the domestic coal industry: two integrated – the captive market and the hierarchical market – and one non-integrated market. Analysis of companies operating from 2010 to 2021 showed that 90 out of 169 businesses (53%) operated as integrated companies (hierarchical and captive VCs), the remaining 79 were classified as market ones.
For each type we measured overall stress resilience (βrescom), indicating the VC degree of recovery from shocks; robustness (βres), the VC ability to withstand (swallow) shocks; adaptability (βrec), the VC flexibility CDS and the ability to recover quickly after a shock. The analysis conducted by the authors showed that the stress resilience of key segments of the coal industry is low and tends to decrease and will only decrease in the long run. The research also found that systemically important companies are in the most difficult situation. They belong to the hierarchical VCs, especially the energyand coal companies, which are mainly focused on foreign markets. Their cooperative survival strategy does not even maintain the current level of stress resilience. Market and relational VCs are in a more favorable position. As a result, the authors conclude that part of the coal companies will inevitably close and for the other part a profound restructuring will be necessary, while the current survival strategies of the companies will not allow to solve this problem by themselves and an active participation of the state will be necessary.