Investigation on biomass steam gasification in a dual fluidized bed reactor with the granular kinetic theory

• Published in: Bioresource technology 2018-12, Vol.269, p.384-392
• Main Authors: Yan, Linbo, Cao, Yang, Zhou, Hongzhiyuan, He, Boshu
• Format: Article
• Language: English
• Subjects: Biomass-steam gasification; Dual fluidized bed (DFB); Eulerian-Eulerian model; Granular kinetic theory
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2018.08.099

•A CFD model for the DFB reactor is built with the granular kinetic theory.•The model is fully validated against a series of experimental data.•The biomass steam gasification in the DFB reactor is comprehensively investigated.•The optimal cold gas efficiency of the DFB reactor is 82.9%.•The DFB cold gas efficiency is the most sensitive to biomass feeding rate. The dual fluidized bed (DFB) reactor is promising to convert biomass into high-quality syngas efficiently. In this work, a three-dimensional model is built based on the granular kinetic theory to predict the biomass steam gasification in dual fluidized bed reactors. The model is firstly validated against a series of experimental results. Then, the effects of some essential operation parameters including the biomass flow rate (Fb), the steam to fuel ratio (Rsf) and the gasification temperature (Tg) on the biomass steam gasification properties in a DFB reactor are comprehensively analyzed with the orthogonal method. In the concerned ranges of the operation parameters, the cold gas efficiency is found to be the most sensitive to Fb and least sensitive to Tg. The optimal cold gas efficiency of the DFB gasifier is 82.9% when Fb, Rsf and Tg are 15 kg/h, 1.5 and 900 °C, respectively, and the H2 mole fraction is 46.62%.