Paper details

Title:

Experimental Study of Wood Char Gasification Kinetics in Fluidized Beds

Author(s):

Reschmeier, R., Karl, J.

Document(s):

Abstract:

Steam gasification is an efficient way for energy recovery from solid biomass fuels. For designing new plants it is necessary to use kinetic data for the gasification of the char remaining back after pyrolysis, because the char gasification is usually slower than pyrolysis and thus the limiting step in designing gasifiers. The objective of this work is to determine “apparent” kinetic constants for wood char gasification in bubbling fluidized bed gasifiers. In order to obtain realistic results for gasification kinetics in fluidized beds, the experiments are carried out directly on a fluidized bed by utilization of gravimetry as measurement method. The samples are char of 6 mm pellets and wood cubes (10 – 40 mm). The gravimetrical measurements result in a measured mass loss as a function of time. As further step this paper shows the reactivities in Arrhenius and half­value period diagrams. The half­value period diagram is introduced as a additional method for presenting results from gasification. This method has many advantages, e.g. that it is independent of gasification models and allows the comparison of any data in literature. The results of the measurements show that the Arrhenius law is fulfilled quite well and that there is no visible influence of the particle size for char from wood cubes within the size range 10 ­40 mm.

Keywords:

char, fluidized bed, wood, allothermal gasification

Topic:

Biomass Conversion Technologies for Heating, Cooling and Electricity

Subtopic:

Gasification for power, CHP and polygeneration

Event:

22nd European Biomass Conference and Exhibition

Session:

2BO.1.3

Pages:

436 - 441

ISBN:

978-88-89407-52-3

Paper DOI:

10.5071/22ndEUBCE2014-2BO.1.3

Price:

FREE