Rotary dryer for thermo sensitive products

Abstract

To achieve the desired drying objectives in thermal sensitive products, such as medicinal plants, the process chosen should happen under minimally controlled conditions, such as, uniformity of temperature and air velocity, minimizing heat loss and with energy viability and efficiency. If possible, the process must occur using equipment with industrial implementation where the evaporation rate can be controlled. The intermittent drying process, which consist of cycles of exposure of the material to heated air (period of effective drying) and tempering (period of no exposure to heated air), is a great option to preserve the product’s quality during the drying process. We propose a new configuration of rotary dryer intended for intermittent drying; observing the configurations of widely applied rotary dryers, the relationship between angular velocity, period and frequency of rotation and laboratory experiments of manufacturing process in intermittent drying. The proposed dryer is efficient for the application of intermittent drying in products with high thermal sensitivity, such as medicinal plants. Making possible uniformity of temperature and air velocity distribution, minimizing heat loss and with energy viability and efficiency, guarantying the product quality.