CO2 capture in power plants- using the oxy-combustion principle

Abstract

In the CO2 capture from power generation, the energy penalties for the capture are one of the main challenges. Nowadays, the post-combustion methods have energy penalties lower than the oxy-combustion and pre-combustion technologies. One of the main disadvantages of the post-combustion method is the fact that the capture of CO2 at atmospheric pressure requires quite big equipment for the high flow rates of flue gas, and the low partial pressure of the CO2 generates an important loss of energy.The Allam cycle presented for NETPOWER gives high efficiencies in the power production and low energy penalties. A simulation of this cycle is made together with a simulation of power plants with pre-combustion and post-combustion capture and without capture for natural gas and for coal.The simulations give lower efficiencies than the proposed for NETPOWER. For natural gas the efficiency is 52% instead of the 59% presented, and 33% instead of 51% in the case of using coal as fuel. Are brought to light problems in the CO2 compressor due the high flow of CO2 that is compressed until 300bar to be recycled into the combustor.