Suchergebnisse

A description of the experimental rig is presented. The effect of combustion air high-temperature (up to 800?C) heating on the model artificial gas combustion process is described. The model artificial gas is a CO-N2 mixture. A comparison of the premixed and diffusion flame lower explosive limits is carried out. Experimental data are compared with open access published data of production of artificial gas-fired CCPP. © 2019 Published under licence by IOP Publishing Ltd. ; The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006.

The priority direction of thermal energy on solid fuels is to increase efficiency and environmental safety, approaching zero emissions of harmful substances. To achieve these goals, they are currently creating new schemes for combined cycle gas turbine units with intra-cycle gasification (IGCC). To improve the efficiency of the IGCC cycle, hot dry desulfurization (HGC) technologies are being developed. HGC uses regenerable sorbents that allow the repeated adsorption of hydrogen sulfide from synthesis gas, among which the most acceptable thermodynamic and operational characteristics are based on ZnO sorbents. The article uses the method of thermogravimetric analysis (TGA) to investigate the development of target reaction capture hydrogen sulfide ZnO-containing sorbent and sorbent reactions with components of synthesis gas in the temperature range up to 1000°C. The sorbent calcined at 900°C shows thermal stability in an inert atmosphere over the entire temperature range studied. Uncalcined sorbents at temperatures of 200 and 600°C emit carbon dioxide in an amount of 1.5-4.5% by weight of the sorbent. At temperatures up to 550°C, the target reaction is basic, and side reactions practically do not develop. The maximum rate of absorption of hydrogen sulfide by the sorbent is observed at a temperature of 600°C. At 500-550°C reactions of a sorbent begin with H2 and CO, at 750-800°C-with carbon, at 850°C-with CH4. The intensity of effect of reagents is defined on degradation of a sorbent by reactionary ability of gases more than temperature. © Published under licence by IOP Publishing Ltd. ; The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006.

The IGCC technology serves to efficiently produce thermal and electrical energy with minimal impact on the environment. In operating IGCC, wet desulphurization is used at temperatures below 200°C. The use of hot desulphurization at temperatures around 500°C will significantly improve IGCC efficiency. The preferred sorbent for hot gas cleaning is ZnO. At temperature of 450-500°C, ZnO begins decomposing because of reactions with syngas components (primarily hydrogen). Steam impedes reaction of ZnO with H2 and increases ZnO thermal stability. Syngas H2/H2O ratio is determined by gasifier operation mode. The purpose of this work is to determine maximum temperature of hot gas cleaning depending on condition of ZnO-sorbent thermal stability and steam-air-blown mechanically activated coal gasifier operation mode. To determine the effect of steam supply to syngas composition, experiments were performed on entrained-flow gasifier (1 MW). Experimental results were processed using thermodynamic analysis to determine idealized syngas composition and CFD-modeling to determine real experiment process parameters. Syngas H2O content was determined by CFD-modeling results. Study of ZnO-sorbent thermal stability depending on H2 concentration and syngas H2/H2O ratio was performed by TGA. As a result of experimentally confirmed thermodynamic calculations, ZnO-sorbent thermal stability was found to increase to 815°C due to steam dilution. © Published under licence by IOP Publishing Ltd. ; The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006.

The thermodynamic analysis of effect of the syngas combustion products (working fluid) thermophysical parameters variation on the economic and energy parameters of the gas turbine cycle is described. The thermodynamic analysis of Brayton cycle performance on various compositions of working fluid within a selected range of control parameters variation is presented. A gas turbine working fluid database was generated based on the analysis of flow diagram and operating regime of the production and design alternative gas-fired CCPP. The relationship between the cycle thermodynamic (pressure and temperature) and thermophysical parameters of the working fluid, which ensures gas turbine cycle maximum work, is derived analytically and supported by the well-known actual data. © Published under licence by IOP Publishing Ltd. ; The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006.

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 work was supported by Decree 211 of the Government of the Russian Federation, contract No. 02.A03.21.0006.