Sorption enhanced reforming of methane combined with an iron oxide chemical loop for the production of hydrogen with CO2 capture: Conceptual design and operation strategy

Abstract

High purity H2 is produced by means of a sorption enhanced reforming (SER) process combined with an iron oxide chemical loop to regenerate the CO2-sorbent High-temperature Fe2O3 particles coming from an air reactor supply the heat required for the calcination of the CaCO3 formed during the SER stage, while generating a concentrated stream of CO2. Fe2O3 is reduced using the PSA off-gas and the calcination of CaCO3 can take place simultaneously in the same reduction reactor. The novel process operates in an arrangement of interconnected fluidized-bed reactors, which facilitates the introduction of a solids separation step between the CaO and reforming catalyst and the denser iron oxide particles. This operation largely reduces the energy demand in the reduction-calcination operation. A sensitivity analysis of the main operating parameters has been made to establish possible operational windows. A hydrogen production efficiency of 88.4% is achievable, while around 98% of the CO2 emissions can be captured in this highly integrated process scheme.