Numerical Investigation of the Effects of Thermo-physical Properties on Tar Intra-particle Secondary Reactions during Biomass Pyrolysis

Abstract

In this study, a coupled transport and chemical kinetic model was used to simulate the effects of biomass thermo-physical properties on intra-particle secondary reactions during convective-radiative pyrolysis of wood cylinder ( ? in a thermally thick regime. Wood cylinder was modeled as a one-dimensional porous solid. Solid mass conservation equations were solved by first-order Euler Implicit Method. Finite volume method was used to discretize the mass conservation equation for tar and gas, the energy conservation equation and the pressure equation. Tri-Diagonal Matrix Algorithm (TDMA) was used to solve the resulting simultaneous equations. Findings revealed that thermo-physical properties influence the extent of intra-particle secondary reactions, biomass conversion time and product yield distribution. Simulation results also showed that density has the highest influence on intra-particle secondary reactions.Keywords: Biomass, pyrolysis, thermo-physical properties, intra-particle secondary reactions1. Introduction