Novel design and multi-objective optimization of autothermal steam methane reformer to enhance hydrogen production and thermal matching

Abstract

This study focuses on the design and optimization of autothermal reforming reactor for hydrogen production. Aiming for higher hydrogen yield, improving the thermal coupling efficiency and mitigating the hot and cold spots, a novel design was conducted and optimized. The configuration improved the performance compared to the traditional model: the highest average temperature was reduced by 24.8%, while the methane conversion improved by 27.2%. The released heat, which can be recovered for further utilization, was significantly increased as the outlet temperature was around 34.5% higher in the novel design compared to the conventional ATR indicating higher thermal efficiency. To further improve this design, a multi-objective genetic algorithm optimization approach was employed to find the optimum catalyst arrangement providing the maximum hydrogen yield with the lowest local wall temperature. Through the optimization, a slight enhancement in hydrogen yield was achieved compared to the design case; however, significant improvement was attained for the thermal behavior compared to the traditional reactor: a decrease in the maximum local wall temperature of 39.3%, the disappearance of the hot spot on the wall and increase in the average outlet temperature of 33.4%. This latter result proves improved heat exploitation in the proposed ATR design.