Steady state modelling of steam-gasification of biomass for H2-rich syngas production

Due to its abundance, biomass is widely used in many engineering applications such as gasification process. Using biomass as a raw material for H-2-rich syngas production can not only reduce greenhouse gas emissions but also promote renewable energy utilization. In this study, a multi-stage model for H-2 rich syngas production from biomass gasification was developed and studied using Aspen Plus simulator. The model is divided into four sub-models including drying sub-model, devolatilization sub-model, tar cracking sub model and gasification sub model. Performance of biomass gasifier was evaluated by predicting the gas yield, lower heating value of produced syngas, carbon conversion efficiency and cold gas efficiency. The maximum H-2 content of 14.9 vol% was achived when S/B and reaction temperature were 1.0 and 1123 K, respectively. The highest CCE of 67.8 % and CGE of 37.9 % were also achieved at 1123 K. An increase in S/B from 0 to 0.5 led to a lower tar yield, which was from 133.557 g/Nm(3) to 127.193 g/Nm(3), and then leveled off as loading increased further from 0.5 to 1.0. The results also showed that during high S/B conditions, the gas-phase chemistry is dominated by water-gas shift (WGS) and Boudouard reactions. (C) 2021 Elsevier Ltd. All rights reserved.