Simulation investigation of drying characteristics of wet filamentous biomass particles in a rotary kiln

摘要

Biomass is an important part of renewable energies and characterized by physical properties and structures, including high moisture content, heterogeneous size, and low density. Wet filamentous biomass particle drying was performed in a rotary kiln, aiming to get the appropriate moisture content. To investigate the drying characteristics of biomass particles, a mathematical model on the heat and mass transfer was proposed. Experiments with filamentous biomass particles under selected conditions were compared to simulations and the feasibility of mathematical models was verified. Furthermore, the transfer of heat and mass between the wet filamentous biomass particle and gas flow was described in terms of rotary drum temperatures, gas flow velocities and gas temperatures. The aim was to gain more information on temperature, moisture content, and the moisture evaporation rate of wet filamentous biomass particles within a rotary kiln during drying processes. The simulation results indicated that the drum temperature could greatly affect the drying behaviors of particles. The temperature and moisture content of particles were marginally affected by properties of the gas flow. The results show that the proposed models offer effective methods to investigate the drying characteristics of wet filamentous biomass particles.