Use of a micro-porous membrane multi-tubular fixed-bed reactor for tri-reforming of methane to syngas: CO2, H2O or O2 side-feeding

A one-dimensional heterogeneous model for four configurations of a reactor, three micro-porous membrane reactors with O₂ (O-MMTR), CO₂ (C-MMTR) or H₂O (H-MMTR) side-feeding strategy and one traditional reactor (i.e., multi-tubular fixed-bed reactor (MTR)), was developed to explain tri-reforming of methane to produce syngas. Effect of various side-feeding strategies on reactor performance containing CH₄ and CO₂ conversion, H₂/CO ratio, and H₂ yield was investigated under the same condition and then described by chemical species and temperature profiles. It was found that use of side-feeding strategies could be feasible, beneficial, and flexible in terms of change in membrane thickness and shell-side pressure for syngas production with H₂/CO = 2 which is proper for methanol and Fischer-Tropsch process, and = 1.2 which is suitable for DME direct synthesis. However, the syngas produced by the MTR is only appropriate for the methanol and Fischer-Tropsch synthesis under the base case conditions. Also, the results show that the micro-porous membrane reactors have higher CO₂ conversion, based on the H₂/CO = 1.2; so these strategies are more environmentally friendly compared to the traditional reactor.