Thermodynamic analyses of near zero CO۲ emission oxy-fuel power plant with atmospheric condensation unit

Thermodynamic analyses of methane fired oxy-fuel power plant, using energy and exergy approaches, are reported for a proposed configuration. Oxy-fuel cycles proposed for removing carbon dioxide (CO۲) by producing a flue gas which is mainly CO۲ and steam. This flue gas mixture makes low temperature physical separation a promising technology for CO۲ capture. Advantages of proposed configuration are the subterfuge of the difficult condenser for the working fluid at vacuum pressure and the saving of the relatively large CO۲ compressors needed for compression to atmosphere. Instead of using a standard condenser, an additional condensation/re-vaporization unit is needed. This condensation/revaporization unit works at atmospheric conditions. Results show that the thermal and exergy efficiencies increase up to ۵۳.۲۵ and ۴۶.۴۵ respectively by adding of condensation/re-vaporization unit and using the waste energies. Also the percentage of vapor in HTT outlet flow is an important parameter that influences the efficiency of the cycle.

کلیدواژه ها:

Oxy-fuel ، condensation/revaporization ، exergy ، economizer ، superheater ، pinch point