Fuel cells are a promising source of clean energy. To find optimal parameters for their operation, modeling is necessary, which is quite difficult to implement taking into account all the significant effects occurring in them. We aim to develop a previously unrealized model in COMSOL Multiphysics that, on one hand, will consider the influence of electrochemical heating and non-isothermal fluid flow on the temperature field and reaction rates, and on the other hand, will demonstrate the operating mode of the Solid Oxide Fuel Cell (SOFC) on carbonaceous fuel. This model incorporates a range of physical phenomena, including electron and ion transport, gas species diffusion, electrochemical reactions, and heat transfer, to simulate the performance of the SOFC. The findings provide a detailed view of reactant concentration, temperature, and current distribution, enabling the calculation of power output. The developed model was compared with a 1-kW industrial prototype operating on hydrogen and showed good agreement in the volt-ampere characteristic with a deviation not exceeding 5% for the majority of the operating range. The fuel cell exhibits enhanced performance on hydrogen, generating 1340 W/m² with a current density of 0.25 A/cm². When fueled by methane, it produces 1200 W/m² at the same current density. Using synthesis gas, it reaches its peak power of 1340 W/m² at a current density of 0.3 A/cm².

Due to climate concerns, most countries are looking for alternative ways to generate energy in a clean, efficient, and environmentally friendly way. Currently, a practical and technically feasible solution can be obtained by integrating a gas turbine and a solid oxide fuel cell to form a hybrid system. Experimental studies of the thermophysical, electrochemical, and other internal processes in solid oxide fuel cells are an expensive procedure, so theoretical tools such as simulations are very important in the analysis and design of solid oxide fuel cell stack systems. In this work, a 3D model of a planar fuel cell was studied. Numerical modeling was carried out, taking into account the flow channel design, the movement of thermal air, and fuel flows. A calculation of the thermodynamic parameters of a solid oxide fuel cell with hydrocarbon fuel has been carried out. In conclusion, some constructive perspectives and recommendations for future research are offered.

RELEVANCE. Steam methane reforming is the dominant method of hydrogen production. Its significant share in global CO₂ emissions highlights the importance of optimizing technological parameters to reduce environmental impact. The developed multi-component model of steam methane reforming in COMSOL Multiphysics is relevant not only due to its applicability for optimizing existing production facilities but also for its potential in developing new methods for utilizing associated petroleum gas. In the context of import substitution in the hydrogen energy sector, this model is also of interest, allowing for the calculation of technological parameters of industrial installations.THE PURPOSE. The aim of the work is to develop and verify a multi-component model of steam methane reforming.METHODS. The research methodology includes the use of experimental data from the literature and industrial indicators for integration into a multi-component model in COMSOL Multiphysics. This enables the modelling of complex chemical interactions under conditions characteristic of the industrial steam methane reforming process.RESULTS. The developed multi-component model allows calculating key parameters of the steam methane reforming process, including the concentration of components (methane, hydrogen, carbon monoxide, and carbon dioxide) and temperature along the reactor. The model successfully describes the chemical interactions between components and takes into account the influence of operating conditions, such as temperature, pressure, and steam/gas ratio, on process efficiency. The model verification was carried out by comparing the modelling results with experimental data and indicators of real industrial processes. Their correspondence confirms the high degree of reliability and suitability of the model for practical application in engineering calculations and optimization of steam methane reforming processes.CONCLUSION. The conclusions made based on the modelling can be used for further improvement of methane conversion technologies, contributing to their efficiency and environmental friendliness. There is also potential for using the model to calculate the stages of installations for the utilization of products from the processing of associated petroleum gas.

Relevance. The continued dependence on the combustion of carbon-based fuels for energy and industry leads to the need to develop various categories of technologies to reduce carbon dioxide emissions. Aim. Development of carbon capture and storage technologies for all stages of fuel conversion and processing, ensuring a low-carbon cycle for the production of electrical and thermal energy, as well as industrial and social facilities. Methods. Chemical, physical adsorption and absorption. Results and conclusions. For large industrial and energy producers, for small energy consumers, it is necessary to be guided by the principles of environmental friendliness and efficiency when implementing the production process, and to increase the percentage of carbon dioxide removal, implement decarbonization technologies at all stages of producing electricity and thermal energy. For the category of CO2 removal at the stage of preliminary fuel conversion, adsorbent compositions using predominantly environmentally friendly and inexpensive natural materials based on bentonite have been developed and tested. The collection capacity of the developed adsorbents is 85–98%. For the category of CO2 removal at the stage of fuel use, a hybrid energy system is presented, including a microgas turbine with heat recovery, a high-temperature fuel cell and other devices and material flows connecting them. A pilot industrial prototype of a 30 kW hybrid energy system will produce heat, electricity, steam, and hot water. In this embodiment, the hybrid system can work as an autonomous energy source for small social and commercial facilities, representing a pilot stage of the engineering and design implementation of the results of an industrial-level hybrid system. For the category of carbon dioxide removal at the stage of CO2 separation from the flue gas mixture after fuel conversion, a block for removing CO2 from flue gases using the absorption method was proposed. Solutions of 15% monoethanolamine, 15% ammonia solution, and 6% sodium hydroxide solution showed the best absorption capacity. It is proposed to equip the hybrid energy system with a CO2 capture unit for complete decarbonization of gas emissions based on closed-cycle technology. The proposed technology for capturing and storing carbon dioxide at the post-fuel conversion stage is characterized by ease of implementation and economic accessibility.