Numerical Simulation of Heat Transfer through the Pyrolysis of Woody Biomass

In order to predict the heat transfer through the pyrolysis of woody biomass, it is important to understand how the volume of the biomass layer reduces. In this report, the visualization of the biomass layer through the pyrolysis has been conducted. The setting temperature of the furnace, T_S, was changed from 350°C to 800°C. The heating rate of the furnace was 400°C/hr. From the experimental results, it was found that the volume reduction process was closely connected with the pyrolysis and divided three regions; i) region of dehydration from biomass (T_S < 310°C), ii) region of pyrolysis of cellulose(310°C< T_S <360°C) and iii) region of pyrolysis of lignin(360°C< T_S ). It was found that the reduction process of the biomass plastic layer through the pyrolysis could be expressed by the first-order lag system with the equilibrium. Numerical simulation for heat transfer through the pyrolysis, which is included the volume reduction process and radiation at the top surface of the biomass layer, has been developed and compared with the experimental results.