iron making course - blast furnace

1

CompanhiaVale do Rio Doce

IRONMAKING COURSE

BLAST FURNACE

August 27th 2010, Belo Horizonte, Brazil

Ironmaking Course

Blast Furnace

Metallurgical reactor where the iron oxides and reducing agents are transformed to liquid hot metal (pig iron) and slag is formed from the gangue of iron burden and the ash of coke.

Thermodynamic conditions (gas composition and temperature) inside blast furnace allows impurities incorporation as silicon, carbon, phosphorus and sulphur to pig iron. Another elements go to the slag.

The blast furnace operates in a countercurrent form. The solid burden flows downward as it reacts with the gases flowing upward. These gases are generated by coke combustion with air injected in the bottom of the furnace.

The blast furnace metallic burden is composed by lump, sinter and pellets. Coke is the reducing and fuel agent of the process.

The blast furnace slag can be sold as raw material to cement industry.

Ironmaking Course

Definition of Volume and Productivity

1) Definition of the blast furnace volumes

1) Total Volume: Is the volume of the BF between the bottom layer of the hearth and the stock line (zero level burden)

2) Inner Volume: Is the volume of the BF between the taphole level into the hearth and the stock line (zero level burden)

3) Work volume: is the volume of the BF between the tuyere level and the stock line (zero level burden)

Ironmaking Course

Blast Furnace Facilities and Cross Section

Top of the furnace

Body of the furnace

Gas Cleaner System

Hot Stove – Cowper’s

Auxiliary equipments

Drilling Machine

Blast Furnace Clay Gun

Torpedo Car

Slag Car

Drilling Machine

Blast Furnace Clay Gun

Torpedo Car

Slag Car

Ironmaking Course

Blast Furnace FacilitiesTop of the FurnaceAll BFs have auxiliary equipment such as:

Conveyor belts for transporting raw materials (iron ore and coke) to the top of the furnace.Hoppers for temporarily storing these raw materials before charging.bell-type charging equipment, where raw materials enter the furnace through the gap created by moving down a small inverted bell. This bell closes and a larger bell (big-end-down) opens to allow material to fall into the shaft below.bell-less charging equipment, the raw materials are dropped into the furnace through a rotating chute. This device allows charging the raw materials into the furnace with appropriate distribution in the radial and angular direction.

Ironmaking Course

Blast Furnace Charging Systems

1. Parallel Hopper Bell Less Top®• Normally 2 hoppers• But sometimes 3 material hoppers

2. Central Feed Bell Less Top®• Static receiving hopper• Rotating receiving hopper

3. Compact Bell Less Top®

4. Mini Bell Less Top®

5. Bell and Double Seal Valve Top

Ironmaking Course

Central Feed BLT® withRotating Receiving HopperCentral Feed BLT® with

Rotating Receiving Hopper

Parallel Hopper TopParallel Hopper Top

Series Hopper Top, Central Feed

Series Hopper Top, Central Feed

3-parallel hopper Bell Less Top® (CST)

3-parallel hopper Bell Less Top® (CST)

Mini Bell Less Top®Mini Bell Less Top®

Central Feed BLT® with R H (Sollac)

Central Feed BLT® with R H (Sollac)

Compact type Bell LessTop®

Compact type Bell LessTop®

Ironmaking Course

Advantages of the Bell Less Top® System:

1. Burden Distribution• More flexibility• More Stable Operation

2. Higher Furnace Top Pressure• Improved Furnace Operational Control

3. Reduced Maintenance• Increased Furnace Campaign Life• Increased Furnace Availability

4. Increased Furnace Production

Ironmaking Course

Blast Furnace FacilitiesBody of the Furnace

The blast furnace has a vertical cylindrical structure externally covered with a shell of thick steel plate and internally lined with refractory.The refractory structure is cooled by water-cooled metal components called cooling box or staves, which are assembled between the shell and the refractory wall.The furnace body is composed by (i) the shaft, which tapers outward from the top,(ii) the belly, which is a straight cylinder,(iii) the bosh, which tapers inward toward its bottom and is located immediately under the belly, and(iv) the hearth, at the bottom of the furnace.

Ironmaking Course

Blast Furnace FacilitiesBody of the Furnace

The shaft, belly, and bosh are usually lined with chamotte brick and silicon-carbide brick, and the hearth is lined with carbon brick. Depending on the size of the furnace, the side wall of the hearth is radially fitted with some 20 to 40 of water-cooled copper tuyeres, which are used to inject the hot blast into the furnace from the hot stoves through the hot-blast main and bustle pipes. Tapholes for discharging hot metal and cinder notches for discharging slag are also installed in the hearth section. The largest BFs at present are about 80m in total height, with a furnace body height of about 35m and a maximum internal diameter of about 16m, and have an internal volume of about 5,750 m3

which produce approximately 13,000 tons of hot metal a day.

Ironmaking Course

Blast Furnace FacilitiesAuxiliary equipments

hot stoves for heating the blast,blowers for feeding the blast,equipment for dust removal, and recovering and storing the gas from the furnace top.Blast furnaces in which pulverized coal is injected through the tuyeres are provided with equipment for pulverizing the coal and feeding it under pressure.In the cast house there is a drilling machine for opening the tap hole and the clay gun to close it when the runner finish.Radial probes for gas analyse and temperature. It is assembled above the burden and cover from wall to centre of the furnace.Profilometer for map the burden distribution and measure the descend of charge.

Ironmaking Course

Blast Furnace OperationBlast Furnace Operation

The furnace can be charged with iron ore lumps, pellets, and/or sinter; coke and flux.These are carried to the top of the furnace with skips or belt conveyors, and are distributed, (not tipped) into the furnace.At the same time, preheated air (around 1250°C) is injected through the tuyeres, which are nozzles at the bottom of the furnace.The coke is partially burned by the injected hot air both to produce heat, and to generate carbon monoxide (CO). Since coke is relatively expensive, some furnaces inject coal, tar, natural gas or oil along with the air as supplemental fuels to reduce coke usage.The carbon monoxide travels upward through the shaft, and removes oxygen from the iron ores on their way down, leaving metallic iron. By the time the charge reaches the base of the furnace, the heat generated there melts the iron. The resulting molten “hot metal” is tapped at regular intervals by opening the “tap hole” in the bottom of the furnace so that it can flow out.The fluxes combine with impurities in the coke and ore to form the slag, which floats on the hot metal and is removed through the “granulation system” (another auxiliary equipment).The hot metal from the furnace is collected in specially-constructed railway containers, called “torpedo cars”. The torpedo cars carry the molten iron to the steelmaking furnace.

Ironmaking Course

Blast Furnace OperationBlast Furnace Operation

Blast furnaces are operated continuously without shutdown for years (nowadays around 20 years) or more. If the furnace were allowed to cool, thermal stresses can cause damage to the refractory bricks.

Eventually, the refractory bricks in the furnace will wear away, and at that point the furnace is emptied and shut down so that it can be relined with new bricks. The period between shutdowns is referred to as a “campaign”.

Hot metal taken directly from the blast furnace contains about 94,5% of Fe, 4 -4.5% carbon, as well as a number of other elements. This is referred to as “pig iron” and is the mainl raw material to be converted to steel by refining in the steelmaking process, which reduces the carbon content and removes other impurities like (P, S , Si) to make stronger and more workable and useful product (=steel).

Ironmaking Course

IRON OREFe2O3 MnO2 P2O5 K2O SiO2 CaO Al2O3

SLAG

PIG IRON

BehaviourBehaviour of Different Elements in the BF Processof Different Elements in the BF Process

Fe3O4

FeO

FeO

Fe (99%) Si (10%)

SiO2 CaO Al2O3P2O5

P (95%)

GA

S

K2O

GA

S

Mn (70%)

MnO

GA

S

Mn3O4

MnO

COKEC S ASH

S (5%)C (12%)

GA

S

Ironmaking Course

Blast Furnace SlagMetals are generally extracted from ores which are always associated with impurities, mainly oxides, called gangue.

During the extraction of the metal, the gangue is removed, by addition of flux, and form the slag, an homogeneous melt (solution) of oxides, which is insoluble in the metal.

Blast furnace slag is formed from the acidic gangue of the metallic burden, ashes of the coke and auxiliary injected fuels and basics fluxes as limestone and/or dolomite.

Four major components amount to about 96% of the slag (CaO, SiO2, Al2O3 and MgO)

During the process, firstly a primary slag is formed during melt process and before the solution of the coke ash components into the slag.

After the the primary slag progress to a final slag.

96%96%Total

8-20%10%Al2O3

28-38%36%SiO2

6-12%10%MgO

34-42%40%CaO

RangeTypical

(CaO+MgO)/ (SiO2+Al2O3)B4

(CaO+MgO)/SiO2B3

CaO/SiO2B2

Typical Slag Composition

Definitions of Basicity

Ironmaking Course

Blast Furnace Cross Section: Internal view

COUNTERCURRENT PROCESS

GOOD PERMEABILITY IN

THE BED IS ESSENTIAL!!!

Raw Materials

Exhaustion Gas

Tuyere

Tap Hole

Slag

Pig Iron

CokeOre

Granular Zone

CoesiveZone

DrippingZone

Hearth

Ironmaking Course

Solid Move Down and Gas Come Up Inside the Blast Furnace GRANULAR ZONE

ORE LAYER

COKE LAYER

TEMP. BEGIN MELTING

COESIVE LAYER

TEMP. MELTING

COKE WINDOW

FLUXODE GÁS SOFTENING

& MELTING ZONE

COKE COMBUSTION

SLAGMETAL

pre-heated air (1100°C) is injected into tuyeres.

combustion of coke (C) with pre-heated air (O2) produces energy to burden heating and reduction.

hot gases cross the bed of coke and ore, heating them and accomplish the chemical reactions of the process.

GASburden top charged is heated

SOLID

iron oxide reduction reactions are started.

the reduced iron oxides are melted.

pig iron and slag are settled in the hearth and separated by density, from where they are tapping.

18

CompanhiaVale do Rio Doce

IRONMAKING COURSE

REDUCTANT/FUEL TO BLAST FURNACE

August 27th 2010, Belo Horizonte, Brazil

Ironmaking Course

Coke Production

Coke is the solid residue from destillation (progressive heating in an air free environment) of a coal blending, in a temperature range of 1000 ~ 1200C, in a series of thin furnaces called coke oven.

The distillation process generates many products like gases, condensables, benzol, tar, etc., sold by the steel industry. The internal consumption of coke oven gas is very important for the global energy balance of the works.

The process could last 20 hours. The incandescent product is discharged by pushing and wet or dry quenched

The environmental aspects related to coke oven emissions are a critical problem. A lot of units have been shut down in the world. INCANDESCENT

COKE INSIDE THE OVEN

Ironmaking Course

Coke Oven View

DrawingDrawing MachineMachine

Charging Car

CokeCoke GuideGuide

Coke Ovem View

Ironmaking Course

Coke Oven Operations

Empty Furnace

Coking

Discharge

Charge Leveling

Charged Furnace

Ironmaking Course

Coke Quality Evaluation

Size Distribution

Tumble Index

CO2 Reactivity

Chemical Analysis

Ironmaking Course

Preparation of the blast furnaceburden

Components of the charge to a blast furnace:

An important aspect of the blast furnace process is the preparation of the charge materials, in order to ensure the gas flow through the burden column. Iron ores (hematite Fe2O3 or magnetite Fe3O4) are charged into blast furnace in the form of lump ores, sinter and pellets. The main components of the charge to a blast furnace are:

• Lump Ore • Pellet • Sinter • Fluxes • Coke

Lump ores:The lump ore are naturally mined ores that are crushed and screened to a certain grain size before their use. However, as a result of preparation and enrichment processes in the iron ore mines to increase the Fe content, very fine-grained ores are generated which have to undergo agglomeration before used in blast furnace. This is done by means of pelletizing and sintering.

Ironmaking Course

Components of the charge to a blast furnace:

Pellets:Pelletizing involves the forming of ore fines (pellet feed) and concentrates with grain sizes of well under 1 mm into pellets measuring around 10 to 15 mm in diameter. To do this, the ore mix is moistened and a binding agent added. The "green" pellets are then formed in rotating drums or on rotary discs . These green pellets are dried and indurated at temperatures of more than 1000 °C. This can take place in shaft or rotary furnaces or on a travelling grate. Pellet plants are generally located at the iron ore producers.

Sinter:The sintering is performed at sintering plants, measuring more than 4 m in width and over 100 m in length. Sintering involves charging a mix of ore fines together with coke breeze, fluxes, in-plant returns and return fines, and igniting the coke breeze contents in the surface by means of gas flames in an ignition furnace. A stream of gas or air is drawn from top to bottom through the mix. A flame front passes through the thick layer over the strand length and agglomerates the mix into coarse lumps of ore. Normally, sintering plants are located on the works sites of the steel producers.


Ironmaking Course

Fluxes:When metal is smelted, the metal is separated from its impurities by melting, with the impurities forming a molten slag on top of the metal. Many of the impurities associated with iron ore are difficult to melt, and so they will not form a proper slag easily, which retards the smelting process.

To make these impurities easier to melt, fluxes are added Limestone (CaCO3) or dolomite ((Ca,Mg)CO3) are two typical fluxes used in blast furnaces.

When a large amount of sulfur needs to be removed from the furnace charge, limestone is the preferred flux. Limestone is also a better flux to use if slag from the blast furnace is to be used as a raw material for cement manufacture.

An important criterion for flux selection is availability and cost, and dolomite is often more readily available and less expensive than limestone.by gas chemical reactions


Ironmaking Course

All the iron ore charged contain oxygen, which has to be removed through reduction in the blast furnace process. To do this, carbon is used.The most important source of carbon is metallurgical coke, which nowadays is produced in modern, environmentally friendly coking plants. The coke ovens, are heated by the coking coal in coking chambers, closed off from the outside air, in the course of which the volatile constituents such as coke oven gas, tar, benzol, hydrogen sulphide and ammonia are expelled, collected and recycled for other uses.

Coke:

Coke performs three main roles in a BF.Thermal role to provide energy to heat and melt the burden;Chemical role to act as a reducing agent and carburize pig iron.Mechanical role to maintain the permeability;

for upward flowing gases.for flow the liquids into hearth

OBS: Pulverized Coal Injected cannot assure permeability in blast furnace burden. The permeable bed is provided by the coke charged to the furnace


Ironmaking Course

Mass Balance for Blast Furnace

Ironmaking Course

Carbon Consumption in the Blast Furnace(Thyssen Stahl AG, Germany)

Pig Iron Carburization 47 11,75

Reducing Gas Regeneration(C + CO2 = 2CO)

100 25,00

Burden Sensible Heat+ Thermal Losses

253 63,25

FUNCTIONCARBON

CONSUMPTION (kg/t HM)

(%)

Total 400 100

Basis : 400 kg C /t , Without PCI

Ironmaking Course

Main Mechanism of Fines Generation on Ironmaking

MECHANICAL STRENGTHRelated to amount of finesamount of fines generated by mechanical force (handling)

DECREPITATIONRelated to amount of finesamount of fines generated by thermal shock

DEGRADATION UNDER REDUTIONRelated to amount of finesamount of fines generated by gas chemical reactions

Ironmaking Course

PROPERTIES OF IRON ORE AND METALLURGICAL COAL AND COKE

Physical PropertiesPhysical

Properties

Chemical PropertiesChemical Properties

Metallurgical And Thermal

Properties

Metallurgical And Thermal

Properties

• Chemical composition: Fe, SiO2, Al2O3, Mn, S, P, Alkalis

• Loss of Ignition (LOI)• Moisture

• Size distribution• Average mean size• Porosity• Mechanical strength

• Mineralogical composition• Microstructure• Crystal size• Morphology• Softening and melting properties • Reduction disintegration

properties

• Chemical composition: Fe, SiO2, Al2O3, Mn, S, P, Alkalis

• Loss of Ignition (LOI)• Moisture

• Size distribution• Average mean size• Porosity• Mechanical strength

• Mineralogical composition• Microstructure• Crystal size• Morphology• Softening and melting properties • Reduction disintegration

properties

IRON OREIRON ORE COAL / COKECOAL / COKE

• Chemical composition: fixed C,ashes, S, P and alkalis

• Macerals: Volatile matter• Replacement ratio• Moisture

• Size distribution• Mean size• Bulk density• Porosity• Mechanical strength

• Combustibility • Mineralogical composition• Microstructure• Crystal size• Morphology• Coke Strength after Reaction• Reactivity

• Chemical composition: fixed C,ashes, S, P and alkalis

• Macerals: Volatile matter• Replacement ratio• Moisture

• Size distribution• Mean size• Bulk density• Porosity• Mechanical strength

• Combustibility • Mineralogical composition• Microstructure• Crystal size• Morphology• Coke Strength after Reaction• Reactivity

Ironmaking Course

COKE / COAL PROPERTIES TO GUARANTEEHIGH BLAST FURNACE PERMEABILITY

• Physical Properties of the Coke and Coal• Narrow size distribution range• High mechanical strength. • Lower blast momentum in raceway

• Lower volatile matter coal injection• Metallurgical properties

• High Coke Strength after Reaction (CSR)• Low ash content to promote lower slag rate

COKE / COAL PROPERTIES TO GUARANTEEHIGH BLAST FURNACE PERMEABILITY

• Physical Properties of the Coke and Coal• Narrow size distribution range• High mechanical strength. • Lower blast momentum in raceway

• Lower volatile matter coal injection• Metallurgical properties

• High Coke Strength after Reaction (CSR)• Low ash content to promote lower slag rate

MAIN DRIVER: HIGHER PERMEABILITYMAIN DRIVER: HIGHER PERMEABILITY

HIGH PRODUCTIVITY ON BLAST FURNACE

BURDEN (Iron Ore) PROPERTIES TO GUARANTEE HIGHER BLAST FURNACE PERMEABILITY• Physical Properties of the Burden

• Narrow size distribution range• Good mechanical strength and low fine

• Metallurgical properties• Low swelling• Good softening and melting properties• Low reduction disintegration properties

• Lower gangue to decrease the slag rate• Lower lump ore rate; higher pellet and sinter

BURDEN (Iron Ore) PROPERTIES TO GUARANTEE HIGHER BLAST FURNACE PERMEABILITY• Physical Properties of the Burden

• Narrow size distribution range• Good mechanical strength and low fine

• Metallurgical properties• Low swelling• Good softening and melting properties• Low reduction disintegration properties

• Lower gangue to decrease the slag rate• Lower lump ore rate; higher pellet and sinter

HIGH

PERMEABILITY

AND

PRODUCTIVITY

BLAST

FURNACE

HIGH

PERMEABILITY

AND

PRODUCTIVITY

BLAST

FURNACE

Ironmaking Course

COKE AND COAL PROPERTIES FOR GOODQUALITY AND LOW PRODUCTION COST

Physical Stability • High mechanical strength and high yield.

• Metallurgical properties• High Coke Reactivity (CRI)• High replacement ratio of the coal injection.

• Low ash, P, and S content.• High Injection rate (PCI)

COKE AND COAL PROPERTIES FOR GOODQUALITY AND LOW PRODUCTION COST

Physical Stability • High mechanical strength and high yield.

• Metallurgical properties• High Coke Reactivity (CRI)• High replacement ratio of the coal injection.

• Low ash, P, and S content.• High Injection rate (PCI)

MAIN DRIVER: LOWER CONSUMPTION AND GOOD CHEMICAL COMPOSITIONMAIN DRIVER: LOWER CONSUMPTION AND GOOD CHEMICAL COMPOSITION

GOOD HOT METAL QUALITY AND LOW COST

METALLIC BURDEN PROPERTIES FOR GOOD QUALITY AND LOW PRODUCTION COST

• Physical Properties of the Burden• Low fines generated and high yield

• Metallurgical properties• Low reduction disintegration properties

• Low S and P• Lower gangue, to decrease the slag rate• Higher lump ore rate

METALLIC BURDEN PROPERTIES FOR GOOD QUALITY AND LOW PRODUCTION COST

• Physical Properties of the Burden• Low fines generated and high yield

• Metallurgical properties• Low reduction disintegration properties

• Low S and P• Lower gangue, to decrease the slag rate• Higher lump ore rate

HIGH HOT

METAL

QUALITY

AND LOW

PRODUCTION

COST

HIGH HOT

METAL

QUALITY

AND LOW

PRODUCTION

COST

* A method to produce high reactivity and strength coke is being investigating by use Ca as catalyze elements* A method to produce high reactivity and strength coke is being investigating by use Ca as catalyze elements

Ironmaking Course

Lump Ore and Metallic Burden Evaluation

Sample degradation during heating on the blast furnace

Decrepitation Test

Tumbler Test ( ISO – 3271) Fine generation due to transfer/drops and abrasion

Reduction Test (ISO 7215/JIS M8713)Evaluate the reducibility of the sample

RDI Test (Reduction Degradation Index - ISO 4696-2)Mechanical strength of reduced sample

MLT Test (Midrex Linder Test)Dynamic reduction to evaluate metallization and degradation

Classify ores into several grades

Chemical analysis

Ironmaking Course

GasGas

SlagLiquid Metal

200

500a

800 900

a1000 1100

a1300 1400

a1600

2000

1400a

1500

Chemical Analysis

Size Distribution

Tumbler Test

Decrepitation

Disintegration

Reducibility

Softening

Melting And Dripping

Blast Furnace

Ore and Metallic Burden Evaluation

Ironmaking Course

REQUIRED PROPERTIES FOR BLAST FURNACE METALLIC CHARGE

BLAST FURNACE INSIDE

Zone Phenomenon Coke

Requered Properties

Sínter Pellet Ore

Granular Pre-heatingReduction

Softening and Melting

Softening and Melting

Gaseous Flow Redistribution

High Temperature Properties

Hearth

Raceway

DesulfurizationS/M Separation

Combustion

Dripping DrippingCarburization

Melting Characteristics

Primary metal behaviour

RDI SwellingDecrepitation

RDICSR/CSI

Reduticibility

Size Distribution

Resistance Resistance

Resistance and

adherent fines

Resistance

Reactivity

Ironmaking Course

INITIAL QUESTIONS

What do you understand as softening and melting?

What do you understand as the cohesive zone?

Ironmaking Course

Blast Furnace Cross Section: Emphasis to Softening & Melting Zone

PERMEABLE REGIONS

ORECOKE

FUSING IRON AND SLAG

PERMEABLE COKE SLITS

ACTIVELOOSE-PACKED

COKE BED

COMPACT

TUYERE

WALLCENTRE

GAS LINES

COHESIVE ZONE

High heat consumption region, where is accomplished:

The greatest part of iron oxides reduction

Metal and slag melting

Boudouard reacion takes place

High thermal gradient region

High pressure drop

Have a strong effect in the gas distribution

Ironmaking Course

Importance of Softening & Melting Zone

Dis

tânc

efr

om tu

yere

leve

l

Pressure (BAR)

2,0 2,5 3,0 3,5 4,0

Pressure drop in Pressure drop in the granular zonethe granular zone

Pressure drop in the Pressure drop in the softening & melting softening & melting

zonezone

Pressure drop Pressure drop in the tuyeresin the tuyeres

(70%)(70%)(15%)(15%) (15%)(15%)

HIGH PCI OPERATION

HIGH PRODUCTIVITY OPERATION

ACTIONS HAS TO BE TAKEN TO RESTORE THE BED

PERMEABILITY IN THIS RESTRICTIVE CONDITIONS

RESTRICTIONS FACTORS TO PERMEABILITY

Ironmaking Course

Softening Start Temperature Ts

Final Melting Temperature Te

∆ Temperature (Te-Ts)

Dripping Start Temperature Td

Reduction degree at 1100 °C R1100

Reduction Degree at Ts Rs

Accumulated pressure loss S value

Maximum Pressure Loss ∆ Pmax

TEST SUMMARY

Ironmaking Course

RIReduction index at 900ºC

R1000Reduction index at 1000ºC

R1100Reduction index at 1100oC

R1200Reduction index at 1200oC

S(S’) valueIntegration of pressure drop with respect to temperature(or time)

Ts200Start of pressure dropover 200mmH2O

Te200End of pressure dropover 200mmH2O

TdStart of dripping of metal or slag

∆T Te200-Ts200

CORRELATION BETWEEN INDEXES AND THE BLAST FURNACE

Ironmaking Course

Upper Heater Power: 45 kW

Maximum T: 1600°C

Lower Heater Power: 55 kW

Maximum T: 1700°C

Heating Rate:

Upper: 5°C/min > 800°C

Lower: 10°C/min > RT

Input Gas:

N2 (22.7 NL/min)

CO ( 9.9 NL/min)

CO2 ( - NL/min)

H2 ( 1.4 NL/min)

Shrinkage and Pressure

Drop Measurement

INDUSTRIAL TESTING EQUIPMENT - VALE

Coke (20 mm)

(20mm)

(70mm)

(20 mm)

MetallicBurden

Load

Load

Coke

Ironmaking Course

0,0

10,0

20,0

30,0

40,0

50,0

60,0

70,0

80,0

90,0

100,0

800 900 1000 1100 1200 1300 1400 1500 1600Temperature (°C)

Shrin

kage

(%)

0

1000

2000

3000

4000

5000

6000

Pres

sure

Dro

p (m

mH

2O)

Shrinkage

Pressure Drop

Ts: 1243°C Te: 1473°C S: 59.51 kg.°C/cm2 dPmax: 5419 mmH2O

TYPICAL RESULTS

Softening Melting

Cohesive Zone

Ironmaking Course

To provide solution in metallic => geo-metallurgy approach

Vale’s Technical Support to CustomersTechnical Methodology

Geological and mineralization

processes

Variabillity and ore types

Ore dressing behaviour

Characteristics and product quality

Behaviour in agglomeration and

metallurgic processes

Ironmaking Course

Lump

PelletsSinter Plant

SinterSinterfeed

Pig iron

BF

Steel

BOF

Stee

l Mill

sPi

lot P

lant

s

Pellet feed

Pelletizing

Para

met

ers

ChemicalPhysicalMetallurgicalMineralogical

ProductivityFuel consumptionProduct characteristics

Reduction indexesCohesive zone properties Permeability of burdenInteraction coke/metallic burden

Sinterização Piloto

Sintering pot

Pelotização Piloto

Forno de Amolecimento & Metallurgical testsPelletizing pot

Softening and meltingfurnace

Characterization

Chemical Analysis

Vale’s Technical Support to CustomersPhysical Simulation (1)

Ironmaking Course

Coke oven

Sintering

BF

FEA

Casting

DRIDirect reduction

BOF

Steel

Hot Metal

Pelletizin

LUMP

Rolling

Global thermal balance

Operations covered by mathematicalmodels at Vale

Vale’s Technical Support to CustomersNumerical Simulation (1)

Ironmaking Course

CFD Model considers:

Fluid and solid flows

Burden distribution

Softening and melting of burden components

Void fraction inside furnace

Temperature dependence of kinetic parameters

Heat and mass balances

Blast Furnace Fluid-dynamic Model(CFD)

Outputs:

Different operational practices

Productivity

Coke rate

Position and thickness of cohesive zone

Operation with high PCI

Environmental aspects 63% Sínter27% Pelotas10% Granulado

63% Sínter27% Pelotas10% Granulado


Ironmaking Course

Simulation motto: “Operate a virtual Blast Furnace”

Increase production ?

Increase thermal reserve ?

reduce coke consumption?

increase PCI ?

Reduce hot metal cost ?

Unstable Stable response

Need for

model/operator

interaction

CFD Operator


Blast Furnace Fluid-dynamic Model(CFD)

Ironmaking Course


Ironmaking Course

Lump

PelletsSINTERING

Sinter

Sinter Feed

PIG IRON

BF

STEEL

BOF

Sintering Neural Network Model

Prediction of sintering parameters and product

BOF model

Mass and heat balance of refining operations to calculate steel costs and quality

Optimization of iron ore mix (linear programming)

Optimum iron ore mix to minimize pig iron costs and/or slag volume in BF

Computational Fluid Dynamic Model

BF inner state predictions

Stee

lmak

ing

chai

n

PHYSICAL SIMULATION

Pelletizing pilot plant

Sintering pilot plant

BF pilot plant

Characterization facilities

Num

eric

al s

imul

atio

n Ph

ysic

al s

imul

atio

n

CVRD products characteristics

Vale’s Technical Support to CustomersPhysical and Numerical Simulation

Ironmaking Course

Knowledge

StrategiesGeneration of Models

INFO Treatment(SIMULATION)

IntelligenceBuild-uo Data Analysis

Physical SimulationNumeric Simulation

Client Situation

Operational Data

INFO

Data Mining

Organizeand Process

INFOrmation Generation(Data Base)

Technical Visits

Data Base Structureand classification

Value in Use (VIU)Concept (1)

Ironmaking Course

Thanks for your attention!!!

iron making course - blast furnace

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