Res. Agr. Eng., 2021, 67(1):8-16 | DOI: 10.17221/48/2020-RAE

Energy and exergy analyses of okra drying process in a forced convection cabinet dryerOriginal Paper

Abiodun Okunola, Timothy Adekanye ORCID...^*, Endurance Idahosa

Department of Agricultural and Biosystems Engineering, College of Engineering, Landmark University, Omu-Aran, Nigeria

A forced convection automatic cabinet dryer integrated with a data logger was designed and fabricated. The okra samples were dried in the dryer at drying temperatures of 50, 60, and 70 °C and at three different load densities of 200, 300, and 400 g at a continuous air velocity of 0.7 m.s^-1. Energy and exergy analyses of the drying process were performed. The obtained results showed that the energy efficiency, energy utilisation, and utilisation ratio increased from 26.59 to 68.24%, 5.47 to 114.36 W, and 0.36 to 0.71 as the temperature increased to 70 °C, respectively. The inflow, outflow, and exergy losses were in the range of 7.02 to 26.14 W, 4.43 to 14.16 W, and 2.59 to 11.98 W, respectively, while exergy efficiency varied from 49.15 to 63.47%. The findings show that exergy efficiencies decrease with an increase in the drying temperature, but increase with a lower load rate. The index of sustainability varies from 2.14 to 2.77, the value increases as the load density decreases while it decreases with a temperature increment.

Keywords: agriculture; food processing; force drying; tray dryer

Published: March 31, 2021  Show citation