Temperature Dependence of the Effective Moisture Diffusivity of Yam (Dioscorea rotundata) Slices Dried Using a Refractance WindowTM Dryer
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Date
2018
Authors
Akinola, A. A.
Ayo, D. B.
Ezeorah, S. N.
Journal Title
Journal ISSN
Volume Title
Publisher
The Journal of the Association of Professional Engineers of Trinidad and Tobago, (JAPETT)
Abstract
The study presents the dependence of the effective moisture diffusivity of yam slices on temperature. A laboratory-scale Refractance WindowTM dryer was used in the investigation. Moisture content measurements of 4.5 mm thick yam slices, dehydrated at water temperatures of 65oC, 75oC, 85oC, and 95oC in the dryer were determined. The experimental drying data obtained was used to estimate the moisture diffusivities, and the activation energy for the process conditions considered. The effective moisture diffusivities estimated using Fick’s second law for 4.5 mm thick yam slices, varied between 1.94 x10-09 m2s-1 and 2.54 x10-09 m2s-1 for the temperatures studied. The activation energy estimated using the Arrhenius type equation was 29.64 kJ/mol for the given temperature range. The effective moisture diffusivities values are slightly higher than those reported in the literature because the investigations were performed at higher temperatures than those found in the literature. Higher moisture diffusivities imply that there is higher moisture movement through the interstices of the slices, which in turn indicates a higher rate of drying. However, the activation energy is within those reported in the literature. Knowledge of these parameters will aid in the design, modelling, and operation of a Refractance WindowTM dryer.
Description
Keywords
Refractance WindowTM Drying; Effective Moisture Diffusivity; Activation Energy; Drying Kinetics; Yam
Citation
Akinola, A. A., Ayo, D. B. and Ezeorah, S. N., (2018), Temperature Dependence of the Effective Moisture Diffusivity of Yam (Dioscorea rotundata) Slices Dried Using a Refractance WindowTM Dryer, The Journal of the Association of Professional Engineers of Trinidad and Tobago, (JAPETT), Volume 46 Number 1, pp 30 - 34. ISSN 1000 7924.