Thermodynamic Assessment of Ginger (Zingiber officinale) Drying in Fluidized Bed Dryer

Abstract

AbstractFluidized bed drying of ginger (Zingiber officinale) cubes (1 cm × 1 cm × 1 cm) with initial moisture content of 87% wet basis (wb) has been carried out at three different temperatures of 45, 50 and 60 °C. A thermodynamic study of the fluidized bed dryer to achieve final moisture content of below 7% (wb) has been presented. The activation energy and moisture diffusivity for the drying process have also been reported. Results showed that drying of ginger in fluidized bed dryer was an effective method that reduced the moisture content of samples of 1000 g to below 7% within 7 hours for all three drying air temperatures. The specific moisture extraction rate (SMER) was 0.3337–0.8368 kg/kWh. The theoretical thermal efficiency was 14.1%, 20.1% and 20.7% for drying air temperature of 45, 50 and 60 °C, respectively. While the overall average exergetic efficiency was significantly high in the range of 64.2–74.7% for specified drying air temperatures. The moisture diffusivity of ginger cubes increased with the rise in air temperature and was between 3.1117 × 10−9 and 3.2508 × 10−9 m2/s, while the activation energy was 73.46 kJ/mol. The calculated values of activation energy and moisture diffusivity were within the range for drying of food products when compared to similar studies in the literature.KeywordsEnergyExergyFluidized bedImprovement potentialGinger drying