Modeling a zero-gap asymmetric electrolyzer: a fundamental approach to overcome the geometric limits
Date
2025
Journal Title
Journal ISSN
Volume Title
Publisher
National Higher School of Technology and Engineering-Annaba
Abstract
The widespread use of reverse osmosis (RO) for seawater desalination has intensified the issue of brine disposal, raising environmental concerns due to its high salinity and chemical load. This study investigates a sustainable valorization route by coupling industrial field data from the UTE Desaladora plant in Skikda, Algeria, with a numerical model of asymmetric zero-gap electrolysis for the recovery of valuable products, notably hydrogen (H₂) and hydroxide ions (OH⁻). A MATLAB-based simulation tool was developed to assess the performance of the electrolyzer under various operational parameters, including voltage, temperature, gas bubble accumulation, Faradaic efficiency, and hydroxide capture factor effects. Polarization curve, has demonstrated that anode activation significantly enhanced the system's efficiency, reducing internal resistance of nearly 70% and increasing performance by up to 65%. The performance assessment showed strong agreement between simulation and experimental results in hydrogen production while greater deviations were observed in current evolution over tome, mainly due to gas bubble accumulation and simplified assumptions in the model. The parametric study revealed that temperature increase reduced cathodic resistance by 46% and increased H₂ output by more than 60%. Similarly, bubble coverage beyond 30% drastically increased ohmic losses, while a hydroxide capture factor above 0.9 severely hindered conductivity and gas production. Discrepancies between simulation and experimental data highlighted the impact of real-world phenomena such as bubble coverage and side reactions, emphasizing the need for more comprehensive and dynamic modeling.
Description
Keywords
Osmose inverse (RO), valorisation de la saumure, cellule à écart nul, simulation MATLAB