To read this content please select one of the options below:

Design and evaluation of a refractance window lab-scale dryer

Shaffic Ssenyimba (Department of Agricultural and Biosystems Engineering, Makerere University College of Agricultural and Environmental Sciences, Kampala, Uganda)
Julia Kigozi (Department of Agricultural and Biosystems Engineering, Makerere University College of Agricultural and Environmental Sciences, Kampala, Uganda)
Peter Tumutegyereize (Department of Agricultural and Biosystems Engineering, Makerere University College of Agricultural and Environmental Sciences, Kampala, Uganda)
John H. Muyonga (Department of Food Technology and Nutrition, Makerere University College of Agricultural and Environmental Sciences, Kampala, Uganda)
Raymonds Mutumba (Department of Agricultural and Biosystems Engineering, Makerere University College of Agricultural and Environmental Sciences, Kampala, Uganda)

Journal of Engineering, Design and Technology

ISSN: 1726-0531

Article publication date: 11 October 2021

Issue publication date: 6 December 2022

92

Abstract

Purpose

Refractance window drying (RWD) has been identified as the method that can give high-quality products at a relatively low production cost. However, knowledge about its use and adoption remains lacking both in academic curricula and industry in the developing world.

Design/methodology/approach

A lab-scale batch RWD of a closed-loop control system was designed, fabricated and evaluated for drying rates, evaporation rate, the energy of evaporation, energy efficiency and throughput. Testing was done using mango and tomato pulps.

Findings

Drying rates at 95°C of 1.32 gg−1min−1 and 0.854 gg−1min−1 at 2 and 3 mm, respectively, for tomato, 0.6 gg−1min−1 and 0.33 gg−1min−1 at 2 and 3 mm for mango pulp were obtained. The dryer had an evaporation rate of 4.63 × 10–4 kg/s and 4.25 × 10–4 kg/s, the energy of evaporation of 1.05 kW and 0.96 kW and thermal energy efficiency of 25.64% and 21.73% while drying tomato and mango pulps, respectively. Dryer throughput of 0.6 kg/h of dried mango Pulp and 0.47 kg/h of dried tomato pulp was obtained.

Originality/value

The designed RWD can be adequately used in laboratory experiments on different products to produce powders. This will enable the transfer of knowledge about RWD technology in developing countries.

Keywords

Acknowledgements

Conflict of interest statement: Authors declare no conflict of interest.

Citation

Ssenyimba, S., Kigozi, J., Tumutegyereize, P., Muyonga, J.H. and Mutumba, R. (2022), "Design and evaluation of a refractance window lab-scale dryer", Journal of Engineering, Design and Technology, Vol. 20 No. 6, pp. 1499-1518. https://doi.org/10.1108/JEDT-12-2020-0523

Publisher

:

Emerald Publishing Limited

Copyright © 2021, Emerald Publishing Limited

Related articles