Modeling fixed-bed coal gasifiers

Journal Article · Fri May 01 04:00:00 EDT 1992 · AIChE Journal (American Institute of Chemical Engineers); (United States)

DOI:https://doi.org/10.1002/aic.690380506· OSTI ID:6945802

Hobbs, M L; Radulovic, P T; Smoot, L D ^[1]

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1. Advanced Combustion Engineering Research Center, Brigham Young Univ., Provo, UT (United States)

In this paper, a one-dimensional model of countercurrent fixed-bed coal gasification is developed, and results are compared to experimental data from commercial-scale gasifiers. The steady-state model considers separate gas and solid temperatures, axially variable solid and gas flow rates, variable bed void fraction, coal drying, devolatilization based on chemical functional group composition, oxidation and gasification of char, and partial equilibrium in the gas phase. Generalized treatment of gas-phase chemistry and accounting for variable bed void fraction were necessary to predict realistic axial temperature and pressure profiles in an atmospheric fixed-bed gasifier. Model evaluation includes sensitivity of axial temperature profiles to model options, model parameters and operational parameters. Model predictions agree reasonably well with experimental temperature and pressure profile data for gasification of eight coal types ranging from lignite to bituminous. The relative importance of char oxidation resistances to bulk film diffusion, ash diffusion, and chemical reaction is identified.

• OSTI ID: 6945802
• Journal Information: AIChE Journal (American Institute of Chemical Engineers); (United States), Journal Name: AIChE Journal (American Institute of Chemical Engineers); (United States) Vol. 38:5; ISSN 0001-1541; ISSN AICEAC
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010300 -- Coal
Lignite
& Peat-- Preparation-- (1987-)
010404* -- Coal
Lignite
& Peat-- Gasification
010600 -- Coal
Lignite
& Peat-- Properties & Composition
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
BITUMINOUS COAL
BLACK COAL
BROWN COAL
CARBONACEOUS MATERIALS
CHARS
CHEMICAL REACTION KINETICS
COAL
COAL GASIFICATION PLANTS
COAL RANK
COMPARATIVE EVALUATIONS
DATA
DEVOLATILIZATION
DIAGRAMS
DRYING
ENERGY SOURCES
EVALUATION
EXPERIMENTAL DATA
FOSSIL FUELS
FUELS
INDUSTRIAL PLANTS
INFORMATION
KINETICS
LIGNITE
MATERIALS
MATHEMATICAL MODELS
NUMERICAL DATA
ONE-DIMENSIONAL CALCULATIONS
PACKED BEDS
PHASE DIAGRAMS
PYROLYSIS PRODUCTS
REACTION KINETICS
TEMPERATURE GRADIENTS
VOID FRACTION