Optimization of methane catalytic decomposition in a fluidized bed reactor: A computational approach

The catalytic decomposition of methane (CDM) in fluidized bed reactors offers a solution for turquoise hydrogen generation with valuable solid carbon as a byproduct. Precise numerical simulations are essential for optimizing reaction processes. This paper presents a novel 2D computational fluid dynamics (CFD) model based on a multiphase Euler-Euler framework for simulating the CDM over a typical Cu-based catalyst in a fluidized bed reactor. The model incorporates an Arrhenius-based deactivation kinetics model considering catalyst deactivation behaviour when carbons are formed and deposited onto the surface of catalysts. The inclusion of catalyst deactivation in the model is crucial for simulating the dynamic fluidization behaviour in the bed layer. The model validation includes determining the minimum fluidization velocity (Umf) and evaluating the CDM performance under various operating conditions, while concurrently investigating the effect of the gas flow rate through a parametric study. The simulation results revealed that decreased flow rates extended the methane residence time in the catalyst bed layer, thereby increasing the conversion rate and effective catalyst lifespan. The findings of this study would highlight the optimization of industrial-scale CDM processes and provide valuable insights for subsequent experimental designs and improvements.

Automated summary

This study presents a computational fluid dynamics model for simulating the catalytic decomposition of methane in a fluidized bed reactor. The model takes into account catalyst deactivation behavior and investigates the effect of gas flow rate. The simulation results show that reducing flow rates can improve reaction conversion rate and catalyst lifespan.