Simulation of roasting process

in fluidized bed using CFD-DEM

Ilia Beloglazov

beloglazov@spmi.ru

National Mineral Resources Uinversity (Uinversity of Mines)

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Process in the high-temperature reactors

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Particle-particle collisions (attrition and adhesion)

Particle-fluid combination

Particle size distribution of various fractions

Destruction and agglomeration of solids

Heat exchange between the gas and particulate material

Heat transfer within the bulk material

Heat transfer between the gas phase and the furnace

lining

Dust discharge fine fraction with countercurrent gases

The chemical reactions

Features of high-temperature reactors

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The complex geometry and configuration

Multi-layer insulation;

Complex nonlinear material properties at the inlet

and outlet of the furnace (density, thermal

conductivity, specific heat, Young's modulus, etc.);

Unsteady equipment operation mode (blades,

loading and unloading devices);

Insufficient information about the process

(thermocouples, pressure sensors).

Combination of methods

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Furnace

Granular materials Gases and liquids Solids

(furnace design

and liners)

DEM(loading / unloading, distribution,

the formation of the layers)

CFD(Calculation combustion,

gas and liquid streams,

temperature fields,

physical and chemical processes)

FEM

(deformation)

Thermo-strength calculations

DEM-CFD

DEM----------------FEM

Modeling of multiple hearth furnace

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Analysis of the loads

generated by the rotating

handles and mixing

material with blades

The system handles and blades6

Multiple hearth furnace

DEM – FEM calculation

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DEM-FEM coupling

Rocky+ANSYS Mechanical

The interaction of the material and the

blades in the multiple hearth furnace

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Analysis of motion and loads bulk material

during the rotation of the blades

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Shaft furnace

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CFD+DEM

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Fields velocities of gases and liquids (CFD)

Fields of temperatures in gases, liquids

and solids (CFD)

Chemical combustion reaction (CFD)

Moving and destruction of the particulate

(DEM)

Chemical reactions in the particle (DEM)

The friction between the particles, the

particles and the wall (DEM)

Unloading the shaft furnace

CFD parameters in furnace

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Loading / unloading and movement of

particles

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Heat transfer in the shaft furnace

DEM + CFD

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Fluidized Bed Reactor Components

The material fluidized is a solid

The medium is gas–liquid–

solid three-phase fluidized

bed

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Kinetic features of the oxidation process

The purpose of oxidizing roasting - maximum removal

of sulfur from sulfide materials. This is achieved by

exothermal reaction between nickel sulfide and free

oxygen:

2Ni3S2 + 7O2 = 6NiO + 4SO2,

Maintaining the right temperature

Intensive mixing

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Flow modes in Fluidized BedsJ. Ruud van Ommen, 2003

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CFD in multiphase modeling

In the case of multiphase flows currently

there are two approaches for the numerical

calculations:

1. Euler-Lagrange approach

2. Euler-Euler approach

2.1. The VOF Model

2.2. The Mixture Model

2.3. The Eulerian Model

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Typical stages of model creation

Definition of the furnace geometry

Generation of the mesh

Choice of physicochemical processes for

simulation

Definition of the liquid and solid phase

properties

Definition of the boundary conditions

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Trial 2D CFD-model

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3D model

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Mesh

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Simulation

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Schematic of a basic fluidized bed for DEM

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DEM

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Thank you for your attention

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Industrial Applications of Fluidized Bed

Reactor Acrylonitrile by the Sohio Process.

Fischer-Tropsch Synthesis.

Phthalic anhydride synthesis.

Methanol to gasoline and olefin processes.

Cracking of Hydrocarbons (Fluid Catalytic Cracking, etc).

Coal combustion.

Coal gasification

Cement clinker production.

Titanium dioxide production.

Calcination of AL(OH)3.

Granulation drying of yeast.

Heat exchange

Absorption

Nuclear energy (Uranium processing, nuclear fuel fabrication, reprocessing of fuel and waste disposal).

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