Dynamic optimization of fixed bed chemical-looping combustion processes

The feasibility of incorporating chemical-looping combustion (CLC) into a combined cycle power plant is explored. We propose a model-based framework to optimally design the cycle strategy for a CLC system, composed of multiple fixed bed reactors. The CLC reactor system is optimally integrated with the downstream gas turbine of a combined cycle power plant, by solving a dynamic program to optimize the temperature profile of the heat removal step out of each reactor, with constraints on the system performance during reduction and oxidation. We demonstrate the feasibility of fixed bed CLC systems to achieve different exhaust temperatures, using synthetic Cu- and Ni-based oxygen carriers. The optimal operating strategy is scaled-up to a system of fixed bed reactors operating in parallel. We show that through process optimization, the batch-operation of fixed bed CLC reactors is void of significant exhaust gas temperature fluctuations and can reach high thermal efficiencies with in-situ CO2 capture.