(249f) Modeling of Steam Methane Reforming Reactor for Electrification through Induction Heating

Steam Methane Reforming (SMR) accounts for 50% of global hydrogen production [1]. The main reforming reaction CH₄ + H₂O ↔ 3H₂ + CO ΔH^298K= 206.1 kJ/mol, being endothermic, is conventionally powered by the combustion of fossil fuels. The combustion heat is transferred from furnace to catalyst bed packed inside tubular reactors. This process contributes approximately 590 Mt of CO₂ annually, representing 1.7% of global emissions [2]. As a decarbonization strategy, heat electrification utilizes low-emission renewable electricity to replace fossil fuel combustion. In this context, NiCo alloy, embedded with ferromagnetic properties, facilitates internal induction heating as a magnetic susceptor for SMR. Technological feasibility has been demonstrated by lab-scale experiments [3]. There is a need for characterizing the performance numerically to explore potential for scale-up and optimization. This work introduces a first principles model of Electrified-SMR (E-SMR) that integrates an electromagnetic hysteresis heat model with a conventional SMR tubular reactor design.

In our study, a comprehensive model for SMR reactor is developed that incorporates mass, heat, and momentum conservation equations, with heat transfer primarily through conduction and convection and mass transfer through diffusion and convection. The classical Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model is used.

Validation against published models confirms the accuracy of our 2D model, which is implemented along axial and radial axes. The results reveal expected theoretical behavior, indicating that conventional reactors are limited by radial heat transfer. This comprehensive 2D model is composed of Partial Differential Algebraic Equations (PDAEs) with nonlinear physical properties. Potential of simplifications to reduce computational demands are investigated.

Additionally, our study realizes the electrification of the reactor by incorporating heat from electromagnetic hysteresis. The energy conservation equation is revised to account for internal heat generation within the pseudo-homogeneous phase, contrasting with conventional SMR models where heat is externally applied and introduced into the model at radial boundary. This adjustment allows for an examination of performance including temperature distribution and energy efficiency in an inductively heated SMR reactor.

This study contributes to the decarbonization of conventional hydrogen production and provides a more sustainable and environmentally friendly energy system for an endothermic reaction.

References:

[1] S. T. Wismann, J. S. Engbæk, S. B. Vendelbo, et al., “Electrified methane reforming: A compact approach to greener industrial hydrogen production,” Science, vol. 364, no. 6442, pp. 756–759, 2019.

[2] D. Latham, Mathematical modelling of an industrial steam methane reformer. Queen’s University Kingston, ON, 2008.

[3] M. G. Vinum, M. R. Alm ind, J. S. Engbæk, et al., “Dual-function cobalt–nickel nanoparticles tailored for high-temperature induction-heated steam methane reforming,” Angewandte Chemie, vol. 130, no. 33, pp. 10 729–10 733, 2018.