Energy Performance Analysis of Convective Drying of Sorghum Gruel Residue

Abstract

This research is concerned with the energy performance analysis of convective drying of sorghum gruel residue. The process was carried out on a hot air dryer conducted at four drying air temperatures of 40, 50, 60, and 70 °C respectively, three different air velocities 0.8, 1.0 and 1.2m/s and three different varieties of sorghum gruel residue, Caudatum,Durra and Guineense respectively. The effects of drying temperature and air velocities on the specific energy consumption, energy efficiency, drying efficiency and thermal efficiency were investigated. The specific energy consumption for Caudatum,Durra, Guineensevarieties ranges from 169530.001 J/kg - 71433.758 J/kg, 170557.25 J/kg - 76732.96 J/kg and 179367.266 J/kg - 83750.923 J/kg respectively while the energy efficiency for Caudatum,Durra, Guineensevarieties ranges from 35.5% - 13.934%, 31.188% - 13.836% and 28.463% - 13.157% respectively. The results of this study also confirmed that the convective drying process is energy intensive and drying fresh agricultural produce with heated-air dryers requires a relatively large amount of energy.