Abstract
This research focuses on testing rotary dryers for the small-scale drying of cherry coffee, using hot air through the conversion of rice husk into thermal with a heat exchanger. Drying cherry coffee with a moisture content of 62% was dried using a rotary dryer and sun drying. Rotary dryer testing for mass variations of 10 kg, 15 kg, and 20 kg. During the drying process, rice husks are not added to the furnace. The results showed that the rotary drying temperature was higher than the sun drying. The final moisture content of sun drying was 13.14%; the average temperature was 29.44 °C for 16 days. The rotary dryer produces final moisture content of 10.71%, 10.45%, and 11.13%. The time required is 1440 min, 1680 min, and 1920 min, respectively. The fastest drying rate occurs at a mass of 10 kg. The highest drying efficiency occurs for a mass of 20 kg. The greater the mass affects the moisture content evaporation, so the drying efficiency is high. During the drying process, there is a decrease in efficiency because the energy absorbed by cherry coffee decreases as the moisture content decreases.