Dry redox reforming hybrid power cycle: Performance analysis and comparison to steam redox reforming

There has been much interest in the use of renewable resources for power generation as the world's energy demand and the concern over the rise in emissions increases. In the near term, however, renewable sources such as solar energy are expected to provide a small fraction of the world's energy demand due to intermittancy and storage problems. A potential solution is the use of hybrid solar-fossil fuel power generation. Previous work has shown the potential of steam redox reforming for hybridization. However, this type of reforming requires some water consumption (which may be infeasible in certain locations) as not all the water can be recovered through recycling. An alternative is to utilize dry (or CO2) redox reforming. In this paper, a system analysis for a CO2 redox reforming hybrid cycle and comparison of cycle and reformer performance between a CO2 redox reformer and steam redox reformer hybrid cycle are presented. The effect of important operating parameters such as pressure, amount of reforming CO2, and the oxidation temperature on the reformer and cycle performance are discussed. Simulation results show that increasing the oxidation temperature or the amount of reforming CO2 leads to higher reformer and cycle efficiencies. In addition, the comparison between the CO2 and steam redox reformer hybrid cycles shows that the CO2 cycle has the potential to have better overall performance.