Enhancing separation efficiency and secondary vapor quality in zinc gluconate evaporation: Application of a structurally innovative vapor–liquid separator

To overcome the low secondary vapor quality and insufficient separation efficiency in zinc gluconate evaporation systems, a novel vapor–liquid separator integrating a bowl-shaped bottom plate and corrugated tubes was developed using CFD simulation. Three separator designs were evaluated: a conventional gravity-settling separator (Model 1), an improved version with a bowl-shaped bottom (Model 2), and a hybrid structure combining a bowl-shaped bottom with corrugated tubes (Model 3). Under varied flow rates, the internal flow characteristics, pressure distribution, separation efficiency, and pressure drop were systematically investigated. Results showed Model 2 improved separation efficiency by 17.2%–20.7% compared to Model 1. Model 3 achieved the highest efficiency of 84.78%, exceeding Model 1 by 26.37% and Model 2 by 6.84%, while maintaining a modest pressure drop increase (5%–7%). Analysis revealed that the combined ”contraction–expansion” channels and micro-vortices generated by the corrugated tubes enhanced droplet coalescence, stabilized interfaces, extended droplet residence time, and improved adaptability to flow fluctuations. This study provides valuable insights and practical guidance for optimizing vapor–liquid separator design and enhancing operational efficiency in zinc gluconate evaporation systems.