Thermal design of 5 kg capacity coffee bean dryer simulator using Geothermal energy

Abstract

A coffee bean dryer simulator that would be able to fully simulate the whole process of coffee bean drying using heat recovered from geothermal energy source has been thermally designed. This simulator is planned to educate people living near the geothermal resources or power plants about the direct use of geothermal energy, especially in coffe drying. The maximum capacity of this simulator is 5 kilogram of fresh coffee bean that is dried using hot air at 45°C and mass flow rate of 0,23 kg/s. The duration of drying is about 3000 seconds which should be adequate to represent the drying process. The heat exchanger proposed for this thesis is a compact heat exchanger with staggered pipe arangement. The total number of pipes is 10 pipes at 36 cm in length and 65 flat plate alluminium fins measured at 0,6m x 0,16m x 0,005m. The fin efficiency value and the overall surface efficiency value are 72% and 73% respectively.