Influence of Surrounding Conditions and Fuel Size on the Gasification Rate of Biomass Char in a Fluidized Bed
Artikel i vetenskaplig tidskrift, 2016

While the operational conditions of a fluidized bed are known to influence the fuel axial mixing, the effect of the resulting axial location of the fuel particles on the char gasification rate remains unexplored. In this work, a laboratory-scale bubbling fluidized bed was used to investigate how the gasification rate of biomass char was influenced by the fuel axial location (during pyrolysis and char gasification), the pyrolysis atmosphere, the fuel size, and the fuel concentration. When pyrolysis at the bed surface was followed by char gasification inside the dense bed the char gasification rate was up to 2-fold lower than the other combinations of the fuel axial location, which held similar rates. Cooling the char after pyrolysis decreased the char gasification rate in all cases studied. The gasification rate increased when the fuel particle size was decreased, and its dependence on the degree of char conversion was also affected. Thus, the operational conditions of a fluidized bed reactor, through modified fuel axial mixing, can influence the char gasification rate. Furthermore, experimental determination of reactivity data in laboratory-scale systems must account for the axial location of the fuel at the desired end-scale, using similar fuel particle sizes.

biomass char

char gasification

fluidized bed

fuel segregation

char kinetics

Författare

Louise Lundberg

Chalmers, Energi och miljö, Energiteknik

Placid Tchoffor Atongka

Chalmers, Energi och miljö, Energiteknik

David Pallarès

Chalmers, Energi och miljö, Energiteknik

Robert Johansson

Chalmers, Energi och miljö, Energiteknik

Henrik Thunman

Chalmers, Energi och miljö, Energiteknik

Kent Davidsson

SP Sveriges Tekniska Forskningsinstitut

Fuel Processing Technology

0378-3820 (ISSN)

Vol. 144 323-333

Drivkrafter

Hållbar utveckling

Ämneskategorier

Energiteknik

Styrkeområden

Energi

DOI

10.1016/j.fuproc.2016.01.002