Performance of greenhouse effect-hybrid type tray dryer in drying cloves

Abstract

The open sun drying method needs to be improved. This study aimed to evaluate the performance of the greenhouse effect hybrid (GHE-hybrid) type tray dryer using solar and biomass energy in drying cloves as a sustainable dryer for future. The dryer has 10 series of thin layers at gap of 10cm and each layer contains of 4 separated trays by 0.80m x 0.75m cross-section. We had run 2 experiments at capacity of 72 and 244kg, respectively. Results showed that increasing the drying capacity will prolong the drying time. The low solar irradiation will also increase the use of biomass energy and the input energy in the system was dominated by biomass energy at level of 75%. The drying temperature ranged from 37 to 46°C. The humidity was relatively high while the air velocity in drying chamber was lower than 0.68m/s and non-uniformly distributed. The moisture of cloves was reduced below 14% in both experiment after 3 and 6 days drying, respectively. The thermal efficiency was about 14 to 15% and the drying efficiency was 17%. The use of GHE-hybrid dryer is promising to be used by farmers sustainably. However, the dryer needs some improvement on air circulation system.