Study on the general dynamic model of biomass drying processes

Abstract

[EN] Nowadays most studies of drying processes dynamics are established on empirical models without clear physical meanings, which could not predict the drying characteristic on different dryers. In order to describe the change of temperature and water content in the cut tobacco in different dryers, a mathematical model based on heat and mass transfer phenomena was developed, and the model employed the relationship of equilibrium moisture content and air humidity as basis, the difference of moisture between biomass and wet air as mass transfer driver, and the difference of temperature between biomass and wet air as heat transfer driver. The drying experiments under different air temperature and humidity are carried out on the batch rotary dryer, and the variance of temperature and moisture content in the biomass is obtained by using infrared thermometer and oven. The model is validated by two parameters with experiment data under each condition of air temperature and humidity. The results show that the drying dynamic model is well on accuracy and universality, and it could be applied on different drying device to predict the characteristic of kinds of drying processes.