CFD Simulation of a Hydrogen-Permeable Membrane Reactor for CO₂ Reforming of CH₄: The Interplay of the Reaction and Hydrogen Permeation

Abstract

A symmetric two-dimensional computational fluid dynamic model of a catalytic membrane reactor for dry reforming of methane is built up. A nondimensionalization method is employed and the governing equations are simplified. Crucial factors including the DamkO ̈hler number (Da), the Pećlet number (Pe), and the relative permeability number (Pm) are obtained. The reaction and hydrogen permeation phenomena in the membrane reactor are visualized and analyzed to reveal the interplay between them. Variation of Da and Pm shows that high hydrogen permeability combined with a moderate catalysis rate is beneficial to obtain a high methane conversion at the retentate side and a large hydrogen amount at the permeate side. The effect of the reverse water− gas shift reaction (RWGS) is also examined, and it turns out that the membrane with high hydrogen permeance could inhibit RWGS, thus declining the steam concentration at the outlet nearly by half (from ∼0.6 to ∼0.3 mol m −3 ). Besides, the effect of counter-current sweep gas and the inflow rate of reactants are investigated and it indicates that counter-current sweep gas configuration is more efficient, especially in the high inflow rate condition. This work also shows that the hydrogen permeation flux profile could be a crucial indicator for membrane reactor design.

Carbon dioxide utilization: A critical review from multiscale perspective

“…[95][96][97][98][99][100] A few CFD studies are available on CO 2 utilization processes. [101][102][103][104][105][106][107][108][109] A brief summary of literature in this regard is presented in Table 4. CFD simulations can be used to carry out the sensitivity analysis of the processes, that is, to evaluate the effect of various parameters (e.g., ratio of liquid to gas flows, pressure, temperature, steam flows, etc.)…”

“…A 2D CFD model of catalytic membrane reactor (for dry reforming of CH 4 ) was developed to visualize the reaction and hydrogen permeation phenomena. 108 The membrane with high hydrogen permeance inhibited the RWGS reaction thus reducing the steam yield and increasing the yield of hydrogen. The study concluded that the most crucial parameter for membrane reactor design is the hydrogen flux permeation profile.…”

A CFD study on the performance of CO2 methanation in a water-permeable membrane reactor system

“…However, it implies that the methanation reaction rate could not match the fast permeation rate. As discussed in the previous literature, the interplay between the reaction and permeation rate is crucial and it determines the performance of MR. 29,[47][48][49] Therefore, in order to make full use of the high membrane permeance, GHSV could be increased to get a higher CH 4 yield. Fig.…”

Zeolite-based catalytic membrane reactors for thermo-catalytic conversion of CO2

“…Based on the above discussions, it would be attractive if an integrated reactor system is constructed to form a synergy of physical and chemical processes. One of the representatives is the membrane catalytic reactor, which has been applied in environmental protections and exhaust gas conversions ( Bian et al., 2020b ; Yang et al., 2013 ; Wang et al., 2020a , 2020b ), such as CO oxidation ( Medrano et al., 2018 ; Peng et al., 2019 ; Bernardo et al., 2008 ; Galletti et al., 2008 ), water-gas shift ( Arvanitis et al., 2018 ; Tang et al., 2010 ; Kim et al., 2012 , 2013a , 2013b ; Wang et al., 2014 ; Zhang et al., 2012 ; Dong et al., 2015 ; Yin et al., 2019 ; Bang et al., 2021 ; Sun et al., 2020 ) and volatile organic compound (VOC) combustion ( Liu et al., 2020c ; Chen et al., 2014 ; Yan et al., 2014 ). Specifically, membrane catalytic reactors are also deemed as a promising candidate for the conversion of CO 2 into value-added products.…”