Isothermal Drying Characteristics and Kinetic Mechanism for Tobacco with Different Water Content

Abstract

The effect of drying temperature on the drying characteristics of tobacco was investigated with different water content. The isothermal drying characteristics and kinetics of three kinds of tobacco on the production line of a tobacco factory in Hubei were studied by halogen water analyzer. The drying characteristics of tobacco with different water content under isothermal conditions were evaluated by water loss characteristics, water diffusion coefficient, and activation energy. The results showed that the drying time of cut tobacco was reduced by increasing the drying temperature within a certain range. The water diffusion coefficient of cut tobacco decreased with the increase of temperature from 70 to 100 °C, and increased with the increase of initial water content. The activation energy of cut tobacco was related to the production process. The activation energy in the experiment was as follows: CT-2 > CT-3 > CT-1. Five drying models were used for non-linear fitting of the drying behavior of tobacco. The fitting degree of the Midilli model was the highest, reaching 0.9944. This data will be useful in the design of tobacco drying equipment.