Combusting and Gasification Using Discrete Phase Method

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Combusting and Gasification Using Discrete Phase
Method

• Combustion Through a Chamber

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BACKGROUND Gasification and Coal Combustion
Ash Deposition
Slagging and Slag Disposal
Fouling Downstream
McDaniel, 2002
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GOVERNING EQUATIONS

• Gas Phase Equations

Turbulent Kinetic Energy
Convection
Generation
Destruction
Diffusion
Dissipation
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GOVERNING EQUATIONS (Continue)
Mass Diffusion Tensor
Conservation of Energy
Mass Rate
Conservation of Species
Molecular Rate of Destruction and Creation of
Species
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Constitutive Equations
Force Momentum Balance
Heat Balance
Surface Reactions
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FORMULATION OF PROBLEM USING FLUENT
Schematic of Domain
Boundary Conditions
Boundary Condition Secondary Air Primary Air Pressure Outlet
Velocity 15 m/s 50m/s ------------------------
Temperature 1500K 1500K 2000K
Turbulence Intensity 10 5 5
Hydraulic Diameter .75 .25 1 m
Oxygen Mass Fraction .23 .23 .23
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SOLUTION
Temperature Profile
Mass Fraction of H2O
Mass Fraction of CO2
Mass Fraction of CO
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SOLUTION (CONTINUED)
Particle Residence Time
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PARAMETRIC ANALYSIS
Mole Fraction of Medium Volatile Coal at Selected
Operating Temperatures as a Function of the Duct
Length
1500 K Case
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PARAMETRIC ANALYSIS
Mole Fraction of Medium Volatile Coal at Selected
Operating Temperatures as a Function of the Duct
Length
1000 K Case
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PARAMETRIC ANALYSIS
Mole Fraction of Medium Volatile Coal at Selected
Operating Temperatures as a Function of the Duct
Length
2000 K Case
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VALIDATION Equilibrium Equations
System of Equations Based On Stoichiometry
Equilibrium Coefficient based on Partial Pressures
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VALIDATION CONTINUE
Values for Fractions
The ratio of CO to CO2 in Fluent was
.247 Difference between Calculated and Fluent is
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Reference

• 1. McDaniel, J., Tampa Electric Polk Power
  Station Integrated Combined Cycle Project Final
  Report. 2002, Tampa Electric Company Tampa. p.
  1-15-1-71.