Abstract
This work experimentally determined drying rates for beds of glass beads containing a concentrated sodium chloride solution and noted the existence of a constant rate period following a falling rate period. A one-dimensional model was developed to interpret the experimental findings. The salt movement carried by up-flow of solution reduced the chemical potential of the solution near the top surface, hence limiting the drying rate. The model suggested that once the salt concentration at the top reached saturation, the process entered the constant rate drying stage. The proposed model reproduced the drying characteristics for the studied medium with a concentrated NaCl system.