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Date submitted2023-09-29
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Date accepted2023-10-25
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Date published2024-08-26
Laboratory studies of transformation of porosity and permeability and chemical composition of terrigenous reservoir rocks at exposure to hydrogen (using the example of the Bobrikovskii formations in the oil field in the northeast Volga-Ural oil and gas province)
The article describes the methodology for laboratory studies of reservoir rock exposure to hydrogen. The stages of sample research and the instruments used in the experiments are considered. A comparative analysis of the results of studies on porosity and permeability of core samples was performed. It was shown that after exposure to hydrogen, the porosity decreased by 4.6 %, and the permeability by 7.9 %. The analysis of correlation dependencies demonstrated a typical change in the relationship of these characteristics: after the samples exposure to hydrogen the scatter of the values increased and the correlation coefficient decreased, which indicates a change in the structure of the void space. Based on the research results, it was concluded that the decrease in porosity and permeability of the core samples occurred due to their minor compaction under the action of effective stresses. The chemical analysis of the rock showed no major difference in the composition of the basic oxides before and after exposure to hydrogen, which points to the chemical resistance of the studied formation to hydrogen. The experimental results showed that the horizon under consideration can be a storage of the hydrogen-methane mixture.
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Date submitted2023-11-27
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Date accepted2023-12-27
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Date published2024-02-29
Physico-chemical aspects and carbon footprint of hydrogen production from water and hydrocarbons
Physico-chemical aspects determine the efficiency and competitiveness of hydrogen production technologies. The indicator of water consumption is especially relevant, since water is one of the main sources of hydrogen in almost all methods of its production. The article analyzes comparative water consumption indicators for various technologies based on published research and actual data from production plants. The volume of water consumption depends on the quality of the source water, which should be taken into account when implementing hydrogen projects in order to minimize the negative impact on the environment. Based on the operating industrial plant, the material balance of hydrogen production by steam reforming was demonstrated, which made it possible to determine the proportion of hydrogen (48.88 %) obtained from water. Currently, the carbon footprint indicator is becoming more important, reflecting greenhouse gas emissions throughout the production chain. According to the results of the total greenhouse gas emissions assessment for hydrogen production by steam reforming (about 10.03 kg CO2-eq/kg H2), the carbon footprint of hydrogen from water (4.2-4.5 kg CO2-eq/kg H2) and hydrogen from methane (15.4-15.7 kg CO2-eq/kg H2) has been determined. Consequently, almost half of the hydrogen produced by steam reforming is produced from water, corresponds to the indicators of “low-carbon” hydrogen and can be considered as “renewable” hydrogen. To make management decisions, an objective assessment in terms of energy and water costs is necessary based on a system analysis by the development of hydrogen energy and the growth of global hydrogen production. The impact of these indicators on the water cycle and global water resources will increase.
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Date submitted2023-03-02
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Date accepted2023-06-20
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Date published2023-07-19
Improving the efficiency of autonomous electrical complex with renewable energy sources by means of adaptive regulation of its operating modes
Renewable energy sources are gradually becoming useful in mining industry. They are actively used in remote, sparsely populated areas to power shift settlements, geological and meteorological stations, pipeline equipment, mobile cell towers, helicopter pads lighting, etc. In comparison with diesel generators, systems with renewable sources do not require fuel transportation, have short payback periods and flexible configuration for different categories of electrical loads. The main obstacles to their spread are instability of generation and high cost of produced electricity. One of the possible ways to solve these problems is to develop new technologies, increase power density of generators and energy storage systems. The other way represents energy saving and rational use of affordable resources. The new solutions for implementation of the second method are proposed in this work. The object of the study is autonomous DC electrical complex with photovoltaic and wind power sources. In such systems the generated power from renewable sources is transferred to consumers via intermediate DC bus, the voltage level of which affects the power losses in the process of power transmission. The vast majority of complexes have a problem that their DC bus voltage is constant, while the optimum voltage level with lowest losses varies depending on the generated and consumed power. Therefore, electrical complexes potentially lose a part of the transmitted energy. To avoid this, a special algorithm was added to automatically adjust DC bus voltage to optimum level according to changes in working conditions. An additional contribution to efficiency improvement can be made by dynamic change of operating frequency in power converters depending on their load. The evaluation based on results of computer simulation showed that in a complex with rated power 10 kW active power losses during its lifetime can be reduced by 2-5 %.
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Date submitted2023-04-02
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Date accepted2023-06-20
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Date published2023-07-19
Integration of renewable energy at coal mining enterprises: problems and prospects
This article addresses the issue of developing renewable energy in coal mining enterprises in the Russian Federation. The study presents a methodology for assessing the technical and economic efficiency of introducing renewable energy sources based on simulation modeling. An analysis of the potential of solar and wind energy for coal mining regions in Russia is conducted. The authors use a custom software developed by them to simulate the power supply system for various scenarios of renewable energy integration, including solar generation, wind generation, solar generation with energy storage, wind generation together with solar generation. Based on the example of the Rostov region, a feasibility study of the considered options is presented. Additionally, the research includes a sensitivity analysis of the investment project in the conditions of uncertainty in the development of Russian renewable energy. The research findings indicate that even in market conditions with CO2 emission quotas and prices at the level of the Sakhalin experiment, renewable energy in coal mining enterprises in Russia remains unattractive and requires additional support.
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Date submitted2021-02-24
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Date accepted2022-04-06
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Date published2022-07-13
Study of the kinetics of the process of producing pellets from red mud in a hydrogen flow
The reduction kinetics of serial phase transitions of iron oxides during reduction to a metallized state with different modes of technical hydrogen supply has been studied and substantiated. The results of the pellets formation when 3-5 % molasses is added to the red mud as a binding reagent are presented. The dependences of the reduction rate of iron oxides on the hydrogen flow rate are obtained. Based on the results of the experiments, a kinetic model was constructed, and with the help of X-ray phase and spectral analysis, it was proved that the agglomerates formed after heat treatment received high strength due to the adhesion of reduced iron particles with red mud particles. The use of a new type of charge materials in melting units will reduce the amount of emissions and dust fractions, as well as increase the metal yield.
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Date submitted2021-03-11
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Date accepted2021-05-21
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Date published2021-09-20
The influence of solar energy on the development of the mining industry in the Republic of Cuba
Cuba is traditionally considered a country with an underdeveloped industry. The share of the mining and metallurgical industries in the gross industrial production of the republic is small – about 3 % of GDP. The development of deposits and the extraction of nickel ores is an important sector of the economy of the Republic of Cuba, since the largest reserves of nickel and cobalt on the North American continent are located on the territory of the country. The development of the country energy system can serve as a growth factor in this sector of the economy. Due to climatic features and impossibility of integrating new capacities into the energy system through the construction of hydroelectric power plants, solar energy is a promising direction. Determining the feasibility of using solar tracking systems to increase the generation of electricity from solar power plants is one of the main challenges faced by engineers and renewable energy specialists. Currently, there are no solar tracking systems in Cuba that can provide information to assess the effectiveness of this technology in the country. The lack of the necessary technologies, as well as the high cost of developing solar power plants with tracking systems, limit the widespread introduction of such complexes. Hence follows the task of creating an inexpensive experimental model that allows assessing the effectiveness of tracking systems in specific weather conditions of the Republic of Cuba. This model will allow in future to increase the efficiency of electrical complexes with solar power plants, which provide power supply to the objects of the mineral resource complex and other regions.
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Date submitted2020-05-13
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Date accepted2020-06-24
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Date published2020-10-08
Barriers to implementation of hydrogen initiatives in the context of global energy sustainable development
Modern trends in the global energy market linked to the Sustainable Development Goals often lead to the adoption of political decisions with little basis in fact. Stepping up the development of renewable energy sources is an economically questionable but necessary step in terms of its social and ecological effects. However, subsequent development of hydrogen infrastructure is, at the very least, a dangerous initiative. In connection with mentioned above, an attempt to examine hydrogen by conducting an integral assessment of its characteristics has been made in this article. As a result of the research conducted, the following conclusions concerning the potential of the widespread implementation of hydrogen in the power generation sector have been made: as a chemical element, it harms steel structures, which significantly impedes the selection of suitable materials; its physical and volume characteristics decrease the general efficiency of the energy system compared to similar hydrocarbon solutions; the hydrogen economy does not have the necessary foundation in terms of both physical infrastructure and market regulation mechanisms; the emergence of widely available hydrogen poses a danger for society due to its high combustibility. Following the results of the study, it was concluded that the existing pilot hydrogen projects are positive yet not scalable solutions for the power generation sector due to the lack of available technologies to construct large-scale and geographically distributed infrastructure and adequate international system of industry regulation. Thus, under current conditions, the risks of implementing such projects considerably exceed their potential ecological benefits.
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Date submitted2017-09-10
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Date accepted2017-11-01
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Date published2018-02-22
Uninterruptible power supply system for mining industry enterprises
- Authors:
- B. N. Abramovich
Immediate problem of compensating falls and deviations of voltage in the power supply systems of mining enterprises in order to ensure the proper level of power supply reliability for the most important technological consumers is substantiated in the article. The main causes of the voltage falls and deviations occurrence in the power supply systems of mining enterprises have been identified. The degree of different nature voltage falls and deviations influence on the dynamic and static stability of power supply systems is established. The necessity of ensuring an uninterrupted and guaranteed power supply mode for continuous technological processes of mining production is shown. The analysis of the existing regulatory documentation in the field of guaranteed and uninterrupted power supply is carried out. Based on the results of experimental studies and mathematical modeling, a relationship has been revealed between formally independent sources of electricity supply from the viewpoint of existing regulatory documentation. The expression allowing determination of cohesion coefficient of two power supply sources is given. The necessity of taking into account the degree of sources interconnection in the synthesis of uninterruptible power supply systems for mining enterprises is justified. The analysis of existing technical means and solutions for reserving power supply for mining enterprises, including modern uninterruptible online power supply systems, own needs power plants, as well as dynamic voltage distortion compensators, is done. The classification of the consumers categories related to possibility of their complete or partial shutdown in emergency modes in case of voltage falls and interruptions is given. System of uninterruptible power supply for mining enterprises based on the combined use of alternative and renewable energy sources, uninterruptible power supply sources and a multi-step automatic reserve transition system, which allows ensuring uninterrupted mode of energy supply for the most responsible consumers of mining enterprises, was developed.
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Date submitted2014-07-20
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Date accepted2014-09-18
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Date published2014-12-22
Use оf renewable energy sources in the coal industry
- Authors:
- A. V. Limanskii
- M. A. Vasileva
There are three fundamental basic documents in energy conservation and energy efficiency today: the Energy Strategy in the period up to 2030; the Federal Law «On energy-saving and energy efficiency and in amending particular legislative acts of the Russian Federation»; and the State Energy Conservation and Energy Efficiency Program in the period up to 2020. In recent years, the upward trend in the use of renewable energy sources (RES) is becoming all the more evident. Until recently, the development of energy has seen a clear pattern: the areas of energy which have developed most are those which have a quite fast direct economic effect. The social and environmental impacts associated with these areas were considered only as incidental, and their role in decision-making was negligible. With this approach, we considered RES only as a future energy source, when traditional energy sources have been exhausted, or when obtaining them becomes extremely expensive and timeconsuming. The primary driver behind the intensive development of RES has been public pressure based on environmental concerns, rather than economic calculations about the future. The economic potential of the world’s renewable energy is currently estimated at 20 billion tons of oil equivalent per year, which is twice the annual output of all fossil fuels. This fact shows us the path of energy development in the near future. In this paper, on the basis of the laws of the Russian Federation, renewable energy in the coal industry is considered. We describe the experience and prospects of the use of mine water and burning rock dumps.
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Date submitted2009-10-14
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Date accepted2009-12-28
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Date published2010-09-22
Geodynamic model of hydrogen sulphide’s formation in natural gas and oil in the process of rocks impulsive compression under conditions оf earthquakes
- Authors:
- A. V. Petukhov
By experiments, conducted on the installation like Bridgeman’s anvil it was determined that under conditions of high pressure, displacement deformations and elastic wave’s effect of short duration, sulphates are reclaimed by hydrocarbons. As a result of this reaction sulphur and hydrogen sulphide are produced.
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Date submitted2009-09-05
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Date accepted2009-11-17
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Date published2010-06-25
Photoelectric method of hydrogen detection
The new photoelectric method of the detection of hydrogen is proposed, based on strong dependence of the photo induced current on concentration of hydrogen in III-V heterostructures with Pd contact. The given influence at a room temperature is stronger on few orders than influence of hydrogen on electric characteristics of solid-state elements in existing sensors. The original design of portable sensor module was developed on the base of photosensitive element and infrared light-emitting diode that meet demands of hydrogen power engineering.