Simulation of sorption-enhanced gasification: H2O staging to a circulating fluidised bed gasifier to tailor the producer gas composition. (1st March 2023)

• Record Type: Journal Article
• Authors: Pitkäoja, Antti; Ritvanen, Jouni
• Is Part Of: Energy. Volume 266(2023)
• Publication Date: 2023-03-01
• Subjects: Sorption-enhanced gasification -- Gasification -- Circulating fluidised bed -- Biomass -- Simulation; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2022.126446
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: Sorption-enhanced gasification (SEG) is an advanced gasification technology for biofuel and biochemical synthesis processes. The SEG process allows tailoring of the producer gas composition for different synthesis processes by adjusting the temperature of the gasifier. Conventionally, the solids circulation rate from the combustor to the gasifier has been used to tailor producer gas composition. In this study, H 2 O staging is investigated in a circulating fluidised bed (CFB) gasifier as an alternative approach. The H 2 O staging can be used to decrease the riser temperature locally to enhance the main chemical reactions. The H 2 O staging as gas and liquid phases were considered in this study. Also, reactor cooling was combined with the staging. A validated one-dimensional CFB gasifier model was used to investigate the process. The simulation results indicate that H 2 O staging and cooling enhance the gasifier's limestone carbonation and water-gas shift reactions. Thus, allowing to tailor the producer gas composition directly by adjusting the gasifier's operating parameters. The methods investigated increase flexibility for operating the SEG CFB gasifier and the reactor system. Understanding different operation methods of the process and their impact on the system's operation enables more flexible use and design of the gasification process. Highlights: Sorption-enhanced gasification process is investigated with modelling. A one-dimensional model is applied to study a circulating fluidised bed gasifier. An H2 O staging to the circulating fluidised bed gasifier is investigated. H2 O staging enhanced the carbonation and water-gas shift reactions. The method enabled direct and flexible tailoring of producer gas composition.