Comparison of thermodynamical potentials of oxy-fuel combustion and regenerative combustion

Abstract

Possibility of the higher combustion efficiency using the oxy-fuel combustion technology has been studied from the thermodynamic point of view. The energy consumption and the change in entropy were calculated for the case of the normal air combustion, the regenerative combustion, and the oxy-fuel combustion. The energy consumption and the change in entropy were compared and discussed for three cases. For the oxy-fuel combustion, the energy required to produce the pure oxygen from the air was considered. The regenerative combustion was the case in consideration of a heat recovery. As a result, the thermodynamical potential of the oxy-fuel combustion is higher than that of the normal air combustion when the exhaust gas temperature is high. The thermodynamical potential of the regenerative combustion depends on the heat recovery efficiency of the regenerative system. The thermodynamical potential of the oxy-fuel combustion is lower than that of the regenerative combustion for the lower exhaust gas temperature, but for the higher exhaust temperature that of the oxy-fuel combustion is higher than that of the regenerative combustion.

Keywords

• oxygen combustion
• oxy-fuel combustion
• entropy
• enthalpy
• normal air combustion
• regenerative combustion