Study on the performance of a baffle demister for improving the separation efficiency of small droplets

Abstract

In order to prevent the gas purified by wet desulfurization from being discharged into the atmosphere with droplets, the efficient demisters are required to separate droplets. This study proposes to regulate the baffle angle to improve the separation efficiency of the demister, and further improve the separation efficiency of small droplets. The influence of baffle angle on the total separation efficiency, grade separation efficiency, and pressure drop of the demister is analyzed. The instantaneous distribution characteristics of droplets and the action mechanism of the baffle are studied. The results indicate that the separation efficiency increases with the decrease of the baffle angle. Within the scope of this study, an optimal separation efficiency is achieved with a 40° baffle angle. Complete separation occurs for droplets larger than 30 µm, while the separation efficiency for droplets smaller than 20 µm is enhanced by 52%−80% in comparison to the wave-plate demister. The separation efficiency of the baffle demister for 10 µm droplets is 2.7–5.8 times that of the wave-plate demisters. The relationship between the baffle angle and the Euler number (Eu) is established. These relationships provide a reference for optimizing demister performance.