Continuous drying process - decrease in flow velocity increases product thickness during desorption drying

摘要

In a method for the continuous drying of granular product, initially dried by evaporation of the adhesive bound water, the product is moved over or along heated platens, followed by a desorption drying stage in which the sorptive bound water is removed, the product being moved over special heated platens and with a greater product thickness than that of the earlier stage. The increase in product thickness is obtained by decreasing the average product flow velocity and/or a step-back flow method. The special desorption drying platens are of hollow construction with perforations to allow the circulation of a gas. This method increases the plant capacity and reduces plant size.