Drying is a process where by a reduction in water content can prevent fermentation or mold growth and slow down chemical changes in foods or fruits. The material used in the drying process is cassava. Drying process is a very long process if done traditionally because it takes a very long time about 3-4 days. Therefore, this study aims to create a mechanical device that can help speed up the drying process. One of the mechanical tools used in the drying process is a rotary dryer type dryer.The heat source is still transferred with the help of the blower. This study aims to create a simpler Rotary Dryer prototype than the existing rotary dryer in the market and heat source used from the gas stove that will directly affect the rotor with out the aid of a blower.
The design of the tool uses a long variation of the drying process on the fin and non-fin rotor with a time of 15, 20, 25 and 30 minutes. The data obtained after the research done on the non fin rotor obtained the reduction of cassava mass of 0.15 Kg, 0.22Kg, 0.29Kg and 0.31Kg. The heat produced is 1637,69W, 1757,50W, 1779,82W and 1900,82W. Efficiency gained that is 35,88%, 34,41%, 32,84% and 32,53%. While on the rotor fin found the reduction of cassava mass is 0.16Kg, 0.25Kg, 0.32Kg and 0.35Kg .. The heat produced is 2293,77W, 2396.68W, 2422.05W and 2593.56W. Efficiency obtained is 48.24%, 45.55%, 43.22% and 43.25%.
The results showed that the effect of time variation is directly proportional to the reduction of heat and heat of hot fluid received by cassava. Because the longer the drying process is done, the mass reduction and heat of the hot fluid will be greater. But the time change is inversely proportional to the thermal efficiency of the rotary dryer. Because the heat provided by the stove is getting bigger while the heat absorption on the product slows down resulting in wasted heat
