Energy and economic characterization of the traditional drying of cocoa beans in greenhouses

Abstract

Drying is a crucial step in cocoa production, for storing and reducing grain humidity. In Colombia, particularly in the Antioquia region, solar energy is used in simple structures called marquesinas. In this work, the authors characterized the process energetically by determining its specific energy consumption (SEC, 27793.9 kJ/kg), the thermal efficiency of the system (η, 12.94%), and specific cocoa drying process cost: 2.27 USD$/kg dry,cocoa (approx. 10442COP$/kg dry,cocoa). At the end, with this information, is constructed grain mass loss curve versus time. The drying on the first day was faster than the following days. The main disadvantage of the greenhouse was that the beans gained moisture at night. For this reason, extra energy and time were necessary to remove the additional humidity acquired by the air condensing over the cocoa beans. This phenomenon decreased the thermal efficiency of the processes and increased its drying time.