Simulation of Air Residence Time Distribution of Spray Droplets in a Counter –Current Spray Dryer

Abstract

This research focused on the development of a fundamental model that can be used to predict the air residence time distribution of spray droplets in a counter-current spray dryer. The proposed model consists of two parallel sections. Firstly, two continuous stirred tanks and a plug-flow in between and secondly, a plug-flow and a stirred tank. A FORTRAN 77 program using Runge Kutta-Mersion subroutine was used to simulate the three first order differential and two linear model equations. The simulated results showed that at high water and airflow rates, more droplets enter into the mixing zones and large amount of moisture content evaporated at a short time interval. There was good agreement between the experimental data and simulated results airflow patterns which make it suitable for industrial application and the standard deviations obtained are within the acceptable limit.