Coffee Cherries Drying Trials Utilizing the Hybrid Solar Dryer

DOI

10.2991/absr.k.210609.075How to use a DOI?

Keywords

Hybrid dryer, coffee, solar energy, fuel combustion energy, overlay thickness

Abstract

Drying process of coffee cherries by sun drying needs two-three weeks to produce dry coffee beans. Efforts have been made by researchers to accelerate this process by introducing various types of solar dryer but their drying performances are subject to be improved. This experimental study aimed to explore the performance of an uniquely designed hybrid solar dryer for coffee cherry drying. Special characteristic of the dryer is electricity independence that makes it possible to be installed wherever demanded. Two experiments were set up in which the dryer was operated by solar energy accompanied with sun drying as a comparison and by the biomass energy generated from wood combustion. Four overlay thicknesses of coffee cherry samples were prepared together with samples for sun drying as comparison for the first experiment and three overlay thicknesses of coffee cherry samples were provided for the second experiment. The result of the first experiment indicated that the curves of coffee cherry moisture content plotted against drying time were linear and the time spends to complete the drying process for the overlay thickness of 4, 8, 12 and 16 cm were 91.42 h, 103,93 h, 109,65 h and 138,75 h respectively which were faster than those of sun drying about 56.04 h, 29,22 h, 24,28 h and 21,98 h respectively. The result of the second experiment demonstrated that utilizing wood fuel supply of 5 kg per hour, the curves of coffee cherry moisture content plotted against drying time were quadratic and the time spends to finish drying process for the overlay thickness of 5, 10 and 15 cm were 61.12 h, 76.23 h and 89.37 h, respectively. The fuel consumption to complete drying for the overlay thickness of 5, 10 and 15 cm were 0.53, 0.33 and 0.26 kg of wood per kg of fresh coffee cherries respectively. It is concluded that the hybrid solar dryer being tested was able to significantly accelerate the drying process of coffee cherries.

Copyright

© 2021, the Authors. Published by Atlantis Press.

Open Access

This is an open access article distributed under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

Download article (PDF)

TY  - CONF
AU  - Y. Yuwana
AU  - E.N. Silvia
AU  - B. Sidebang
PY  - 2021
DA  - 2021/06/11
TI  - Coffee Cherries Drying Trials Utilizing the Hybrid Solar Dryer
BT  - Proceedings of the International Seminar on Promoting Local Resources for Sustainable Agriculture and Development (ISPLRSAD 2020)
PB  - Atlantis Press
SP  - 497
EP  - 503
SN  - 2468-5747
UR  - https://doi.org/10.2991/absr.k.210609.075
DO  - 10.2991/absr.k.210609.075
ID  - Yuwana2021
ER  -