Non-stationary and LCA analysis of impurity adsorption using Kanuma clay and HAS-Clay in a Bio-H production system

Abstract

In recent years, fuel cell (FC) applications have shown potential in the reduction of greenhouse gas (GHG) emissions, leading to an increase in demand for hydrogen fuel. The current source of hydrogen is generally fossil fuel origin. Therefore, for mitigating GHG emissions in the hydrogen production stage, we focused on the biomass-derived hydrogen (Bio-H2) production process. In this study, we discuss the environmental impacts of Bio-H2 through the biomass pyrolysis process of Blue Tower (BT) biomass gasification. The bio-syngas contains H2S, HCl, and NH3 as impurities, which can reduce the performance of FCs. In our previous experimental studies, we used hydroxyl aluminum silicate clay (HAS-Clay) as an adsorbent for removing impurities. However, based on the life cycle assessment methodology, it was found that the impact of HAS-Clay was higher, indicating that the environmental contribution of the one through operation using HAS-Clay would be lower. Thus, in this study, using Kanuma clay, which is a natural resource and lower impact adsorbent, we used the desulfurization test and designed an optimal process to mitigate its eco-burden and maintain removal performance. Finally, using the dynamic process simulator of ANSYS fluent (2020 R1), we compared the proposed process to the conventional process in terms of plant performance and evaluated the environmental impacts. The results showed that there was a 12.3% reduction in GWP due to the replacement of Kanuma clay and HAS-Clay as compared to ZnO, a chemical adsorbent.