Mass Transfer and Liquid‐Film Formation in a Spray Tower for SO₂ Removal in Sodium Hydroxide Solution

Abstract

Abstract Spray towers allow for controlling air pollution in which a liquid is sprayed in small droplets to produce a large interfacial area for mass transfer between a gas and a liquid phase. An experimental study of a spray tower for removing SO 2 is described. The experiments were carried out under different operating conditions by varying the gas velocity, liquid flow rate, and SO 2 concentration. SO 2 removal efficiency, volumetric mass transfer coefficient, and liquid‐film formation as a result of the collision of droplets against the tower wall are investigated. Removal efficiency and volumetric mass transfer coefficient are analyzed as a function of gas velocity, liquid flow rate, and SO 2 concentration, while liquid‐film formation is evaluated as a function of tower height. The results indicate high removal efficiency. Correlations to predict the volumetric mass transfer coefficient are also proposed.