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

• Published in: Energy (Oxford) 2022-01, Vol.238, p.121616, Article 121616
• Main Authors: Liu, Zhibin, Zhao, Chuankai, Cai, Longhao, Long, Xinman
• Format: Article
• Language: English
• Subjects: Aspen plus; Biomass; Calorific value; Cold gas; Devolatilization; Drying; Emissions; Energy utilization; Free-tar syngas; Gasification; Greenhouse gases; Renewable energy; Simulation; Steady state models; Steam; Synthesis gas; Tar
• ISSN: 0360-5442; 1873-6785
• DOI: 10.1016/j.energy.2021.121616

Due to its abundance, biomass is widely used in many engineering applications such as gasification process. Using biomass as a raw material for H2-rich syngas production can not only reduce greenhouse gas emissions but also promote renewable energy utilization. In this study, a multi-stage model for H2-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 H2 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/Nm3 to 127.193 g/Nm3, 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. [Display omitted] •Air-steam gasification of biomass was modeled using Aspen Plus.•The proposed model was successfully validated with the reported results.•The maximum H2 content of 14.9 vol% was achieved at S/B of 1.0 and reaction temperature of 1123 K.•Increase in S/B from 0 to 0.5 led to a lower tar yield, and then leveled off for further steam loading.