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This work investigated the influence of the operating parameters of the gasifier (pressure, temperature of the syngas at the outlet of the gasifier and the O2/CO2 ratio in the blast) on the composition of the syngas in relation to the Allam cycles and oxy-fuel IGCC. Thermodynamic modeling of the operation of Shell (Allam cycle) and MHI (oxy-fuel IGCC cycle) gasifiers by the entropy maximization method was carried out. For the Shell gasifier, a significant increase in methane concentration with an increase in pressure to 40 MPa has been revealed; it indicates the need to make changes to the syngas gas cleaning system. The optimal temperature at the outlet of the gasifier (1100°C) has been found for the MHI gasifier. At this temperature, there were high values of CO and H2, and, hence, the heating value of syngas. For both gasifiers, the most theoretically reasonable ratio of O2/CO2 in blast was 0.3, at which CO reached almost maximum values and decreased its growth rate. © Published under licence by IOP Publishing Ltd.

A combined steam-gas plant with in-cycle steam gasification of coal and hot gas purification is considered as a promising technology for increasing the efficiency of energy production with simultaneous reduction in environmental impact. To in-tensify steam-air gasification, mechanical activation of fuel is used; it consists in high-stress grinding in a mill-disintegrator. The supply of steam to the gasifier allows an increase in reactivity of fuel, suppression of sorbent decomposition in the unit of hot desulfurization, reduction in the steam load on the shift reactor, increase in useful external work of gas turbine expansion, reduction in nitrogen oxide formation, and general increase in the efficiency and ecological compatibil-ity of energy generation. On the other hand, a significant amount of steam can deteriorate the heat balance and efficiency of the gasifier. In this work, the influ-ence of the steam/fuel ratio on steam-air gasification of mechanically activated Kuznetsk coal in a flow reactor was studied experimentally. The excess air coeffi-cient was maintained constant and equal to 0.51, which corresponded to a temper-ature at the reactor outlet of about 1100 °C. When steam was supplied, the fuel and air-flow rates were adjusted to ensure a constant gas-dynamic regime. To evaluate the obtained regimes, the heat and material balances were compiled. A positive effect of steam on characteristics of the gasification process was revealed. For the studied coal, the maximum degree of coal conversion and the calorific value of synthesis gas are achieved with a steam/fuel ratio of about 0.4 kg/kg. © 2021 Society of Thermal Engineers of Serbia.Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia.This is an open access article distributed under the CC BY-NC-ND 4.0 terms and conditions

The aim of the work is using an experimental-computational method to study the process of air-steam-blown entrained-flow gasification of coal with multistage air supply. To achieve this aim, the experiment was conducted on a plant consisting of a swirler into which coal and air are supplied, and a reaction chamber into which steam and multistage air are supplied; the experiment was numerically simulated using a validated CFD model; and the process under study was analysed using the obtained experimental and calculated data. The conducted experimental and computational studies of air-steam-blown gasification allowed determining the effect of steam supply and multistage air supply on the features of the gasification process. Steam injection lowers the temperature of the gas mixture and increases the concentration of hydrogen due to the hydrogasification reaction. The air supply to the reaction chamber increases the temperature of the mixture due to the burning of part of the syngas, while the syngas heating value is reduced by an appropriate amount. The maximum concentration of the syngas combustible components (and hence syngas heating value) is observed before the second point of air supply to the reaction chamber. © Published under licence by IOP Publishing Ltd.

For industrialized economies, a strategically important area is developing active methods for industrial use of carbon dioxide emissions to produce marketable products. A rational approach to the problem of clean generation should be based on the complete coordination of the output parameters of the CO2 discharged from the power plant and the input (working) CO2 parameters of the consumer, which will reduce the cost of emissions conditioning, and maintain power plant efficiency. The CO2 parameters from fossil fuel power plants and CO2 consumers' potential were analyzed for three main indicators most sensitive to power generation: the amount of CO2, operating pressure, and purity considering the level of technological maturity and market attractiveness. Based on the analysis, three types of energy-industrial symbioses were identified with a cost-effective Power Plant - Consumer model without an intermediate unit for matching input and output parameters of CO2 (without a CO2 capture and conditioning system). A hybrid solution combining modern IGCC and the latest thermodynamic cycles based on oxy-fuel technologies is offered as a generalized configuration of the energy part of the promising complex. The concept and key technological solutions of the promising energy-industrial symbiosis "Power Generation Unit - CO2-based production"are being developed at Ural Federal University. Such symbiosis ensures the low-cost supply of CO2 to industrial consumers using mineralization technology. It will allow utilizing not only technogenic carbon but also ash, slag, and construction industry waste to produce marketable products (cement, concrete, and other materials). © Published under licence by IOP Publishing Ltd.

The problems of tightening harmful emissions standards and meeting commitments to reduce greenhouse gas emissions require the development of environmentally and economically viable technologies to capture CO2 and its subsequent utilization. The integration characteristics of the generic technologies for CO2 emission utilization from energy industries with a short, medium- and long-term commercialization prospects are considered, depending on the level of technological maturity and market attractiveness. Potential CO2 consumers were classified according to the central most sensitive energy generation parameters: volumes, pressure, and purity, depending on the CO2 capture processes parameters and types of thermal power plants. The CO2 utilization unit principles designed for full CO2 capture by various industries under the Paris agreements are considered. The joint analysis of the operating and prospective power plants, leading industrial technologies based on CO2 consumption, has revealed three types of energy-industrial symbioses representing a cost-effective "Power Plant - CO2 Consumer"model. This model operates without CO2 capture and conditioning unit and has the efficiency close to the traditional power plant without emissions utilization. Critical technology solutions are being developed for one of these types. © Published under licence by IOP Publishing Ltd.

In this paper the costs of creating a high-temperature air heater intended for the integrated gasification combined cycle unit developed by the authors are estimated and are compared with a steam boiler. The results can be used not only in the further development of the integrated gasification combined cycle plant under consideration, but also be interesting to specialists involved in the development of various high-temperature heat exchangers. © 2020 Institute of Physics Publishing. All rights reserved.

High temperature heat exchangers are needed in various energy technologies to increase their efficiency. The article is devoted to the optimization of the design of a high-temperature air heater used in the integrated gasification combined cycle plant, developed in Ural Federal University. In the air heater, air with a pressure of 2 MPa after the cycle compressor is heated by coal combustion to a temperature of 900°C before it is fed into the combustion chamber of a gas turbine. The air heater is developed as a pulverized coal fired boiler with air heating in tubular radiation-convection heating surfaces. The authors propose a new design of a high-temperature air heater, which allows reducing the cost of the expensive high-temperature part of the unit 1.8 times compared with the previous design. A computer simulation of the boiler section is carried out to verify the proposed design solutions. © Published under licence by IOP Publishing Ltd.

A gas turbine cycle working fluids group based on their production technology and application is presented. The energy parameters analysis procedure of unclosed and closed gas turbine cycles is described. The comparison of the effect of the working fluids thermophysical and thermodynamic properties variations on the useful work l0 of both unclosed and closed gas turbine cycles is presented. The effect of the fuel gas composition variation on the useful cycle work l0 is revealed. The effect of the working fluid thermophysical properties variation on the gas turbine cycle optimal combination of thermodynamic properties (T3 and P3 ) is presented. © Published under licence by IOP Publishing Ltd.