Kinetics of CO sub 2 gasification of fast pyrolysis black liquor char

Journal Article · Sat Sep 01 00:00:00 EDT 1990 · Industrial and Engineering Chemistry Research; (USA)

DOI:https://doi.org/10.1021/ie00105a007· OSTI ID:6224312

Li, J; van Heininger, A R.P. ^[1]

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1. Dept. of Chemical Engineering, McGill Univ., Pulp and Paper Research Institute of Canada, Montreal, Quebec (CA)

The CO{sub 2} gasification rate of black liquor char (BLC) was studied in a thermogravimetric analysis setup at temperatures between 600 and 800{degrees} C. The BLC was prepared via fast pyrolysis of dry solids of spent liquor of the kraft wood pulping process. BLC gasification by CO{sub 2} is well described by Langmuir--Hinshelwood type kinetics. The gasification rate of BLC is 1 order of magnitude larger than that of a high surface area activated carbon impregnated with 12% Na{sub 2}CO{sub 3}. Also, the gasification rate of BLC remains high at sodium/carbon ratios where the rate of Na{sub 2}CO{sub 3} impregnated chars would normally be strongly reduced. The rate of BLC gasification was also influenced by the drying method and pyrolysis heating rate. Using a scanning electron microscope and energy dispersive spectroscopy (SEM-EDS) mapping and line scan techniques, it is shown that the unique gasification properties of BLC are caused by a very fine distribution of sodium in the carbon matrix. The present data suggest that internal surface area measurements rather than swelling tests might be more appropriate to characterize combustion properties of black liquors.

• OSTI ID: 6224312
• Journal Information: Industrial and Engineering Chemistry Research; (USA), Vol. 29:9; ISSN 0888-5885
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
09 BIOMASS FUELS
CHARS
THERMAL GRAVIMETRIC ANALYSIS
COAL GASIFICATION
CHEMICAL REACTION KINETICS
WOOD
PYROLYSIS
BLACK LIQUIDS
CARBON DIOXIDE
COMBUSTION PROPERTIES
HIGH TEMPERATURE
SCANNING ELECTRON MICROSCOPY
SODIUM
SOLID WASTES
ALKALI METALS
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMICAL REACTIONS
DECOMPOSITION
ELECTRON MICROSCOPY
ELEMENTS
FLUIDS
GASIFICATION
GRAVIMETRIC ANALYSIS
KINETICS
LIQUIDS
METALS
MICROSCOPY
OXIDES
OXYGEN COMPOUNDS
PYROLYSIS PRODUCTS
QUANTITATIVE CHEMICAL ANALYSIS
REACTION KINETICS
THERMAL ANALYSIS
THERMOCHEMICAL PROCESSES
WASTES
010404* - Coal
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& Peat- Gasification
010409 - Coal
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090900 - Biomass Fuels- Processing- (1990-)