Effect of Superficial Gas Velocity on Bubbling Fluidized Bed Behaviour in a Biomass Gasifier

Cornelius Agu
Department of Process, Energy and Environmental Technology, University of South-EasternNorway, Porsgrunn, Norway

Britt M.E. Moldestad
Department of Process, Energy and Environmental Technology, University of South-EasternNorway, Porsgrunn, Norway

Ladda ner artikelhttps://doi.org/10.3384/ecp20170158

Ingår i: Proceedings of The 60th SIMS Conference on Simulation and Modelling SIMS 2019, August 12-16, Västerås, Sweden

Linköping Electronic Conference Proceedings 170:24, s. 158-163

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Publicerad: 2020-01-24

ISBN: 978-91-7929-897-5

ISSN: 1650-3686 (tryckt), 1650-3740 (online)


This study investigates the behaviour of bubbling fluidized beds in biomass gasification processes based on the variation of superficial gas velocity at different temperatures and air flow rates. In the paper, the operating window is defined as the gas velocity between the minimum fluidization and slugging velocities, which are computed using the correlations in the literature. The analysis shows that the operating gas velocity depends on the amount of char accumulated in the bed. An increase in the char accumulation results in higher minimum fluidization and slugging velocities of the bed mixture. This therefore suggests that the gas velocity ratio required to achieve the desired operating fluidized bed regime is higher when the biomass accumulation is considered.


biomass, gasification, air-fuel ratio, CPFD, bubbling fluidized bed


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