Traveling Microwave Reactor: Design Challenges and Solutions

Abstract

With the increasing importance of renewable electricity as a primary source of energy on the planet, the importance of electricity–based technologies in process industries is expected to rise as well. Microwave heating is a well–known electricity–based industrial technology that is used in a variety of commercial applications.

This work addresses challenges and explores opportunities for industrial–scale utilization of microwave heating in heterogeneous catalytic gas-phase reactors. Through critical analysis of microwave applicators, the thesis highlights the limitations of traditional cavity–based reactors and underscores the potential of traveling–wave systems for achieving uniform heating profiles in heterogeneous catalytic flow reactors. The contribution of the thesis lies primarily in the design and optimization of traveling microwave reactors (TMRs). Challenges associated with catalyst heating profiles and process scale–up are addressed by introducing a coaxial waveguide structure and a tailored catalyst loading pattern. The TMR model demonstrates its effectiveness in accurately predicting temperature profiles and reaction dynamics along the reactor through simulation studies and experimental validation. Furthermore, the thesis introduces the Reverse Traveling Microwave Reactor (RTMR) as a novel reactor concept aiming to minimize temperature gradients along the catalyst bed by periodic reversal of microwave irradiation. Simulation–based studies showcase the RTMR’s potential in achieving temperature uniformity within the catalyst bed, offering new insights into reactor design and scale–up considerations for microwave–assisted catalytic flow processes.