Evaluation of Solid Desiccant based Drying System for Energy-EfficientDrying of Agricultural Products

Abstract

Drying air conditions of agricultural produce including the temperature and humidity affect the quality andappearance of the dried product. High temperature and higher humidity cause to loss of nutrient and color. Controlof the latent load of drying air prior to use for drying seems more effective approach for the preservation of delicateand temperature sensitive nutrient present in agricultural produce. Desiccant drying system (DDS) removes themoisture from the drying air and makes it possible to dry at low temperature and low humidity. In present study thepertinence of DDS with two desiccant materials LiCl and Silica gel were analyzed in order to find the optimumdrying conditions for wheat and rice. Results showed that in case of desiccant material LiCl, process airtemperature found higher and humidity lowers, thus provided more pressure deficit and speedup drying ascompared to the silica gel. The value of drying potential per watt also showed that desiccant material LiCl foundmore economical to use as compared to silica gel for all range of regeneration temperature. However for differenttype of grains, optimum ranges of regeneration temperatures is different i.e. 55-60ºC for wheat and 60-65ºC for rice.