(222f) Electrified Steam Methane Reforming with High Frequency Magnetic Induction

The chemical industry has been one of the major contributors of greenhouse gas (GHG) emissions, accounting for nearly one third of global CO₂ emissions. Many of these industrial processes require the heating of volumetric reaction media to high temperatures, with applications ranging from the selective capture of gases (e.g., CO₂, SO₂, etc) and the production of fuels and chemicals (e.g., biomass decomposition, hydrogen and syngas generation, etc) to the processing of materials (e.g., baking of bricks, sintering of minerals, etc). One solution to mitigating these carbon emissions is to utilize renewable and clean electricity, instead of fossil fuels, to provide endothermic heat for these processes. Amongst the wide range of environmentally friendly electrification heating concepts currently being explored, inductive heating is an established method for clean, efficient, and rapid heating and is used industrially in the processing of raw iron and silicon materials. However, an underlying challenge to date is understanding how inductive heating can be adapted to heat volumetric media uniformly and its integration with different reactor configurations. An extensive and thorough understanding of the design of three-dimensional heating susceptors, catalyst integration with the susceptor, and co-design of power electronics with the susceptor are required.

In this study, we discuss the potential for inductive heating to serve as an electrification heating solution for heating steam methane reforming catalytic reactors. Metallic open cell lattice susceptors were washcoated with the zirconia and impregnated with Ni solution to act as both heating susceptors and supported catalyst material. With a combination of analytic and numerical electromagnetic optimization, the lattice geometry was optimized to produce uniform volumetric heating across the susceptor, minimizing temperature gradients within the reactor and minimizing heat transfer limitations between the susceptor and catalyst. A focal point of our research effort was in addressing heating efficiency, which has been limited in prior studies by poor energy transfer efficiency between the magnetic coils and susceptors due to operation at low frequencies. In combination with parametric studies on the effects of circuit frequency and coil geometry on heating efficiency, we utilize a high frequency inductive heating scheme, based on megahertz frequency power electronics, to enable susceptor heating at near unity efficiencies. We evaluate the reactor system's performance through experiments at different residence time and temperature and experimentally demonstrate that operating the setup at MHz scale frequency can lead to heating efficiencies above 90%, comparable to resistive heating method.