Multiscale Modeling of Radio Frequency Reactor Coupled Catalyst Heating for Ethylene Production

Abstract

Ethylene is the petrochemical compound with the highest production worldwide. Whether reactors are heated by direct fired heating or indirect heating via steam, manufacturers rely on economies of scale to overcome inherent thermodynamic inefficiencies while burning fossil fuels. New approaches to supply energy to chemical reactor systems can reduce energy waste created by traditional techniques while enabling large scale facilities to use other sources of raw materials and energy. Electromagnetic (EM) induction heating is one potential solution for providing energy efficiently to reactor systems. By taking advantage of the nature of radio frequency (RF) waves, heterogeneous-catalyst can be precisely targeted for heating inside the reactors. Site-selective heating can significantly reduce the energy requirements of the process by providing heat at reaction sites and reducing unnecessary heat transfer elsewhere. Other advantages to an EM enhanced system include rapid volumetric heating, broader turn-down capacity, and reduced process footprint.The purpose of this work is to establish a multiscale computational fluid dynamics (CFD) model that can be used to emulate the proposed process mechanics at the macroscale and microscale. At the macroscale, coil geometry (coil diameter, gap between coils, distance between coil and susceptors) is investigated to elucidate coil design and effects on heating rates. In the microscale, the oxidative (CO2) dehydrogenation (ODH) of ethane is explored using different catalysts and possible catalyst/susceptor configurations with heat supplied by an EM susceptor. This multiscale method can also be applied to electrochemical systems.