Modeling sulfur dioxide absorption by fine water spray.

A novel theoretical model was developed to determine the removal efficiency of sulfur dioxide using fine water spray. The droplet pH, diameter, S(IV) concentration, sulfur dioxide concentration, and liquid-to-gas ratio are found to influence the absorption of sulfur dioxide by the fine water spray. The results demonstrate that the absorption of sulfur dioxide by the fine water spray increases as the droplet diameter falls. The concentration gradient between the interface of the gaseous and liquid phases causes the absorption of sulfur dioxide by the droplets to increase as the initial S(IV) concentration decreases or the sulfur dioxide concentration increases. The results indicate that the performance of the fine water spray in removing sulfur dioxide is generally improved by reducing the droplet diameter or the initial S(IV) concentration, or by increasing the sulfur dioxide concentration, the droplet pH or the liquid-to-gas ratio. The proposed model reveals the parameters that should be controlled in using a fine water spray device and a method for improving its performance in removing sulfur dioxide.