Steam methane reforming over a catalyst-coated wire with Joule heating: Heat and mass transfer study in catalyst-wire system

Abstract

Steam methane reforming (SMR) driven by renewable electricity has emerged as a promising technology for low-carbon hydrogen production. This study focuses on SMR over a catalyst-coated wire heated by Joule heating, aiming to explore the complexities of heat and mass transfer within the catalyst-wire system. Numerical modeling utilizes to evaluate the effect of various parameters such as temperature (up to 1400 K), Reynolds number (up to 2000), and catalyst layer thickness (1 mm, 2 mm, and 5 mm), on energy and material balance. The maximal temperature wire was chosen as control parameters and volume heat flow from hot wire to catalyst layer was changed to change the maximal wire temperature. The numerical model was validated against experimental data. The results reveal that a 1-mm-thick catalyst layer behaves as thermally thin (Bi < 0.1), with catalyst temperature closely resembling wire temperature. However, increasing the catalyst layer thickness to 5 mm leads to a notable rise in the temperature difference between the catalyst layer and the wire. Moreover, thicker catalyst layers of 5 mm suffer from intra-layer diffusion limitations, which can reduce overall process efficiency. It was established that inside catalyst layer for a temperature range above 1200 K the complete methane conversion close to equilibrium value can be achieved. • Steam methane reforming over catalyst-coated hot wire by renewable electricity. • Catalyst layer of 1 mm is thermal thin with negligible intra-layer diffusion limitation. • Catalyst layer of 5 mm suffers from intra-layer diffusion limitation. • Close to equilibrium methane conversion at a low Reynolds number. • High catalyst layer temperature makes unfavorable carbon formation.

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