Development of a high and low temperature Agro-dryer using biomass and an integrated moisture laden extractor fans

Abstract

Agricultural produce spoilage from microbial activity is a major course of concern. One of the means to reduce microbial activity is to reduce the amount of moisture content in crops. This is most often achieve by sun drying or using cabinet dryer. However due to varied drying temperature and moisture contents of crop this research have developed and tested a high and low temperature cabinet suitable for drying crops with high and low moisture contents requiring different air temperature in order to retain the nutritional value of agricultural produce. The drying rate for the respective produce are 0.08875, 0.02, 0.1275, 0.025, 0.07 and 0.07 kg/h for tomatoes, pepper, onions, bitter-leaf, fish and plantain respectively, with the high temperature chamber experiencing higher drying rates than the low temperature chamber due its higher temperature. The maximum recorded temperature in the high and low chamber are 69 °C and 52 °C, 60 °C and 45 °C, 75 °C and 55 °C respectively for day 1, day 2 and day 3 of testing. Peak high-chamber efficiency was 49% and consistently exceeded the low-chamber peak of 35%. This demonstrates that the developed
high and low temperature cabinet dryer is both functional and efficient for multi-crop drying application.