Feasibility Study of the CO2 Regenerator Parameters for Oxy-Fuel Combustion Power Cycle

Abstract

The atmosphere carbon dioxide content grows subsequently due to anthropogenic factors. It may be considerably mitigated by the development of thermal power plants with near zero emissions. A promising way is the transition to the semi-closed oxy-fuel combustion power cycles with carbon dioxide and water vapor mixture as a working fluid. However, their wide implementation requires reduction of the metal consumption for the highly efficient regeneration system. This paper discloses the results of feasibility study for the regeneration system of the prospective oxy-fuel combustion power plant. The effect of operating parameters on the cycle energy efficiency, overall dimensions, and the cost of the regenerator was determined. Underheating increase in the regenerator by 1 °C leads to the net efficiency factor drop of the oxy-fuel combustion power cycle by 0.13% at average and increases fuel costs by 0.28%. Increase of pressure drop in the hot channel by 1% leads to efficiency drop by 0.14%. The optimum set of design and operating parameters of the feed heating system has been determined, which ensures the best technical and economic indicators of electrical power generation: the minimum cumulative costs are achieved when underheating in the regenerator is 20 °C and pressure drop in the hot channel is 4%, under the use of S-shaped fins channels.