ABSTRACT

 Drying of turmeric rhizome using a passive solar dryer was studied with the objectives to find out the moisture content, the total drying time and to evaluate the performance of the solar dryer. 600g of turmeric was procured from National Root Crop Research InstitLite (NRCRI). The turmeric Rhizome initial moisture content of 20g was determined in the oven and weighed. Turmeric was sliced longitudinally and spread on the drying trays in the solar dryer. The weight of the Turmeric rhizome was measured at 1-hour interval until it reach equilibrium moisture content. The average temperature obtained for inlet and outlet temperature of the drying chamber were 34.03 and 32.11°C. Average humidity of the drying chamber was 64.05%, It took ten days and fifty-seven sunshine hours to dry the turmeric rhizome of the two varieties local haldi and red streaked from 593.95 to 95.71g and 593.95 to 84.71g respectively. The average valves of the performance parameters for the solar dryer, drying efficiency (%) of the dryer, Energy consumption (Kwh/kg), drying rate (g/hr), final mass (g) were 40.05 and 45.5%,76.24 and 66.24kwh,77.2 and 72.6g/hr, 95.71 and 84.61g. respectively. At the inlet collector, the humidity tends to be lower while the temperature is high. Two varieties of the turmeric Rhizome were compared, the Red Streaked drying rate is faster due to less moistLire and Local haldi drying rate is slow due to high moisture. The calculated collector efficiency was 26.05%.