Characteristics of a 10 kW honeycomb reactor for natural gas fueled chemical-looping combustion

Chemical-looping combustion (CLC) is already treated as a promising way to capture CO2 in the utilization of fossil fuels. The most used reactors for the CLC are fluidized-beds, in which the fuel conversion and the conversion of fuel to CO2 is determined by the bed height. Here in this study, the CLC in an advanced 10 kW honeycomb reactor is studied by using natural gas as the fuel and Fe2O3 as the oxygen carrier. In the honeycomb reactor, a honeycomb chamber consisted by the oxygen carrier is employed to enhance the contact area and the disturbance between the fuel gas and the oxygen carrier. Both of these two enhancement are benefit for achieving a high CH4 conversion and a high conversion of CH4 to CO2. The experiment results show that three stages of Fe2O3 to Fe3O4, Fe3O4 to FeO and FeO to Fe are occurred in sequence during the reduction reaction of Fe2O3 and CH4 in the honeycomb reactor. The behaviors and the relationships for these complicated reactions, the oxygen transfer rate, the CH4 conversion and the conversion of CH4 to CO2 at different stages are further experimentally studied. Additionally, to increasing the conversion of CH4 to CO2 in the continuous operation, the characteristics for the honeycomb reactor in redox cycles are also experimentally investigated. Our study here would be expected to provide a new method for developing the energy and environment compatible systems.