A two dimensional Euler–Lagrangian model of wood gasification in a charcoal bed – Part I: model description and base scenario

Abstract

In this article we present a parameter study for an Euler–Lagrangian model with application to wood gasification in fluidized beds. The bed material consists of charcoal and wood only. The detailed model involves processes of heat up, drying, particle shrinkage, primary and secondary pyrolysis, gasification, and tar decomposition. Initially we introduce a bidisperse mixture of 12,000 charcoal particles idealised as perfect spheres. The collision model is based on a linear discrete element method (DEM) and allows to account for multiple particle–particle contacts and collisions. This first part of the study gives a detailed description of the model with all submodels and assumptions. The base scenario mimics experimental conditions of a lab-scale fluidized bed reactor. The base scenario will be used in the second part of the study as the base of comparison for a comprehensive parameter study. The data shown for the base scenario include temporal data for the reactor outlet temperature and species concentrations (including tars) as well as barycenter data for the solid phases. The data gained from the simulation is also compared to available experimental data.