FLUIDIZED BED DRYING OF CORN, BEAN AND CHICKPEA

In the agricultural industry, drying is a very important process to preserve food products. Also, fluidized bed drying is the most common preferred process due to its advantages. In this paper, the effects of the fluidizing air temperature and velocity on the drying performance of corn, beans and chickpeas were investigated by carrying out a series of tests. Laboratory-scaled fluidized bed drying apparatus was used. Batch drying experiments were conducted by applying three different air temperature and two different air velocities. In addition, the Henderson and Pabis model was used to compare experimental and model results. Lastly, activation energy values were determined for the particles. Results revealed that the drying air temperature has the greatest effect on the drying kinetics of particles, whereas air velocity has a small effect. It was also observed that bean, corn and chickpea particles have different drying curves during the drying period (5,400 s). Mean absolute errors, root mean square errors and mean absolute percentage error were used as performance criterion between experimental and model results. The activation energy values of the particles showed the same pace as similar studies in the literature. PRACTICAL APPLICATIONS Drying is energy-intensive and has a negative environmental impact due to fact that most of the thermal energy needed is obtained by combusting fossil fuels. From 12–25% of national industrial energy consumption is attributed to thermal dehydration in industrial nations. As global economies prosper, the demand for energy for drying will increase. Thus, there is need to understand this operation well and to ensure that it is carried out as efficiently as possible within the economic constraints of the market. It is also important to keep abreast with the current drying technologies, as well as the emerging new ones. The drying of various feedstocks is needed for one or several of the following reasons: need for easy-to-handle free-flowing solids, preservation and storage, reduction in cost of transportation, achieving desired quality of product, etc. In many processes, improper drying may lead to irreversible damage to product quality, and hence a nonsalable product.

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