Interconnected pyrolysis and gasification of typical biomass in a novel dual fluidized bed

• Published in: Energy conversion and management 2022-11, Vol.271, p.116323, Article 116323
• Main Authors: Zhou, Chunbao, Chen, Lei, Liu, Chenglong, Wang, Jun, Xing, Xuyang, Liu, Yang, Chen, Yuanxiang, Chao, Li, Dai, Jianjun, Zhang, Yingwen, Yu, Mengyan, Yuan, Yanxin, Yao, Bang, Li, Yan
• Format: Article
• Language: English
• Subjects: Biochar; Dual fluidized bed; Energy balance; Gasification; Pyrolysis
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2022.116323

[Display omitted] •A novel dual fluidized bed of pyrolysis and gasification was designed and built.•Total energy yield was 63.54–84.95% and energy efficiency reached 63.79–82.47%.•Wood char had highest methylene blue (600.15 mg/g) and iodine (397.08 mg/g) values.•Highest heating value and H2 content of pygas were 10.14 MJ/Nm3 and 23.91 vol%.•Carbon fixation ratio was 38.61–53.27% with peanut shells being the highest one. A novel 50 kg/h dual fluidized bed (DFB) was designed and constructed, and pilot study of interconnected pyrolysis and gasification/activation were conducted. Four typical biomass materials were investigated and compared in DFB system. Pyrolyzer temperature and riser temperature were 480–550 °C and 800–850 °C, respectively. Dolomite were used as bed material, and superheated steam was adopted as the fluidizing gas in pyrolyzer and transport gas in loop seals. Biochars were comprehensively characterized and analyzed, and were potential matrix for carbon-based materials. Biochar from wood sawdust was the best carbon-based material matrix compared to other biochars with the highest adsorption capacities of iodine (397.08 mg/g) and methylene blue (600.15 mg/g). Phenols and benzenes (total content of 63.26–97.36%) were the richest components in all bio-oils. Non-condensable pyrolysis gas from corn cob had the highest heating value (10.14 MJ/Nm3) and largest H2 content (23.91 vol%). The total energy yield was 63.54–84.95%, while energy efficiency was 63.79–82.47%. The carbon fixation ratio was in the range of 38.61–53.27% and the highest carbon fixation ratio was 53.27% from peanut shells. The advantages and feasibility of interconnected pyrolysis and gasification/activation technologies by DFB for biomass utilization and carbon capture were assessed in this pilot study. DFB is a promising technology to achieve carbon negative economy, and deserves more research in the future.