(502d) Efficient, Wireless, and Volumetric Heating in Scalable Electrified Resonant Chemical Reactors

Induction heating is a promising method for internal volumetric heating in thermochemical reactors, however, efficiency losses from parasitic currents in nearby metallic structures and dissipation in the coil still present significant challenges. From the viewpoint of wireless energy transfer technology, one approach to achieving high efficiency lies in in the principle of resonance. Efficient wireless energy transfer through resonance has long been applied to transfer power in biomedical, robotic, consumer electronic systems, but the concept of resonance has not been explored for converting electrical energy to heat in induction heating systems. Recently, we demonstrated a resonant susceptor design that achieves ultrahigh heating efficiency and uniform volumetric heating. This design is made by rolling a metal sheet into a structure termed a “Swiss Roll” (SR).

Our initial study showed that the SR structure exhibits a well-defined resonant frequency defined by the number of turns, spacing, inner radius, and thickness. The heating profile may also be manipulated by controlling the geometry and the dielectric properties of nearby materials such as catalysts and supports. These factors necessitate rigorous co-design of the SR geometry, high frequency power electronics, and catalyst integration, which we have investigated using both analytic models and FEM simulations. Our SR-based induction reactor exhibits several key features: (a) Volumetric heating at resonance, with either uniform or spatially designed profiles—unlike conventional non-resonant inductive reactors that suffer from limited radial heating profile tunability. (b) Ultrahigh coupling efficiency, with over 99% of energy delivered directly to the reaction zone. (c) Promising scalability, enabled by the high coupling efficiency, which allows for robust structural design without the typical trade-offs from parasitic losses in metallic supports or enclosures.

In this talk, we discuss how we can advance the SR concept, previously made from a solid metal sheet to one made from metal mesh. We term the susceptor MeshSR and show that this susceptor topology can significantly enhance scalability, manufacturing feasibility, and process intensification potential of resonant reactors. We will cover the following points. First, we co-design the geometry of the MeshSR with the dielectric properties of the catalyst particles, achieving a very low volumetric fraction (<5%) occupied by the mesh. This enables easy packing of catalyst particles in a fixed-bed reactor with minimal disruption to catalyst loading and gas mixing, while still maintaining uniform volumetric heating across the reactor zone. Second, we experimentally validate the concept by constructing a 5-inch-diameter MeshSR baffle packed with K₂CO₃/Al₂CO₃ catalyst particles, which we use to perform reverse water–gas shift (RWGS) reaction at 550 °C under various flow rates. Our results show that the MeshSR achieves near-unity heating efficiency and sustains high conversion rates at elevated flow rates, highlighting its potential for process intensification. Third, we also present a COMSOL Multiphysics simulation that accurately recovers the experimental results. Furthermore, we use this model to project the performance of MeshSR in an industry-scale reactor, demonstrating its potential to save on both capital and operating costs through efficient energy use and simplified construction.