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SINTERING PLANT
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DEFINITION OF SINTERING
Sintering is a process of agglomeration of fine mineral
particles into a porous and lumpy mass by incipient fusion
caused by heat produced by combustion of solid fuel within
the mass itself.
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TYPES OF SINTER
NON FLUX SINTER
FLUXED SINTER
SELF FLUXED SINTER
SUPER FLUXED SINTER
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SCHEMATIC DISTRIBUTION OF THE ZONES IN CHARGE DURING SINTERING
ON THE SINTER STRAND
ZONE OF SINTERING
ZONE OF
CONDENSATION
OF MOISTURE
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RAW MATERIALS USED FOR SINTERING
1. Iron ore fines
2. Flux ( lime stone & dolomite )
3. Coke breeze
4. Waste Materials:a). Flue dust ( From Blast Furnace but added in RMHP )
b). Mill scale ( From Slabbing Mill, H.S.M.&CCS)
c). L.D.Slag (From S.M.S.)
d). Lime dust ( From R.M.P.)5. Sinter return ( Own generation)
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MAIN SECTIONS OF SINTERING PLANT
1. RAW MATERIAL SECTION.( For crushing of coke and flux )
2. STOCK BINS AND PROPORTIONING SECTION
( For storing,proportioning & mixing )
3. SINTER MACHINE SECTION
( For sinter making )
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COKE CRUSHING BY FOUR ROLL CRUSHERS( 08 Nos. CAPACITY 16 T/Hr. EACH )
MIX COKE FROM C.O. COKE RETURN FROM B.F.
( - 15mm ) ( - 25mm )
+ 15 mm TO B.F.
MIXED WITH SINTER
-15 mm TO FUEL
STORAGE
- 15 mm
- 3 mm-3 mm TO STOCK BINS
6 mm
2 mm
(NUT COKE SCREEN)
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STOCK BINS AND PROPORTIONING SECTION
A. TO STOCK RAW MATERIALS :
There are three similar series of over head bunker andconveyors to feed three sinter machines at a time. Each series
contains 23 bunkers . Materials are stored in the bunkers in
following order :
BUNKER No. TOTAL BUNKER MATERIAL1 6 06 Iron ore fines
7 13 07 Crushed flux ( - 3 mm )
14 17 04 Crushed coke ( - 3 mm )
18 01 Waste materials
19 20 02 Cold sinter return
21 01 Hot sinter return
22 23 02 Lime dust
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B. FIXING OF FEED RATE :
For sending raw mix to sinter machine for sintering, fixation of
feed rate of materials is done considering capacity of the sinter
machine and quality requirement of blast furnace.
Feed rate fixed is :
Iron ore fines 250 T/hr.Flux 75 T/hr.
( Feeding of Flux depends on available lime in sinter required
in blast furnace.Available lime means CaO SiO2in sinter.)
Coke 20 T/hr.
Waste materials 20 T/hr.
Sinter return 60 T/hr.
Lime dust 02 T/hr.
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PROPORTIONING OF CHARGE
ELECTRONICCONVEYOR SCALES
ELECTRONIC
FEEDER
VIBRO FEEDER
O/F FLUX COKE W/M S/R L/D
A 1
CONV.
TO
S/M -1
A 3
CONV.
TO
S/M -2
A 5
CONV.
TO
S/M -3
PRIMARY
MIXING
DRUM
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RAW MIX
SRC
D/C
D/F C/S
SHAKER GATE
RAW MIX BUNKERS
ELECTRONIC FEEDERS
BALLING DRUMS
SHUTTLE DISTRIBUTOR
FURNACE
CHARGE HOPPER
DRUM
FEEDER
SINTER MACHINE
WIND BOXES
1 2 25 26
MAIN GAS COLLECTOR
TO EXH.
TO EXH.DUST POCKETS
(36Nos.)
WATERDRUM
COOLER
-5mm
+8mm TO BF
-8mm
TO STOCK BINS
-5mm TO STOCK BINS (HOT SINTER RETURN)
SINGLE ROLL CRUSHER
HOT SCREEN
COLD SCREEN
DISC FEEDER
SINTER MACHINE PROCESS FLOW
WATERWATER
H/S
RAW MIX
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Sinter Machine Specification for each machine
There are three Sintering machines
Length - 78 M
No. of pallets - 130
Sintering area
252M2Bed height - 480mm
Exhauster - 02 Nos.
Aspirator - 02 Nos.
Cooler Blower- 06 Nos.
Balling Drum - 02 Nos.
Drum Cooler - 01 No.
Straight line Cooler - 01 No.
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CRANES Location & Capacity
Name Location Tons
G/Crane Fuel Storage 10
C/Crane C/Crane Building 05
H/Crane H/Crane Building 10
S/B S/B Tops 05
A1/A2 A1/A2 Area 15
B/Drum B/Drum Area 50
Exh. Exh Buld. 50
Sinter Machine Machine Build. 30
Bay 1,4& 5 ARS 15
Bay 6 ARS 03
MDP MDP 05
JN 12 S/B Top 15
Other then these 46 nos. of Telphers are also there.
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WHAT IS
AGGLOMERATION Agglomeration is defined as the process to
prepare a suitable Blast furnace feed forsmooth, proper and efficient running of theBlast furnace operation.The process of agglomeration can be classifiedas follows:i) Briquetting.
ii) Nodulising.
Iii)Vacuum Extrusion process.iv) Sinteringv) Pelletizing.
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ADAVANTAGES OF
AGGLOMERATION Ability to use all kinds of Raw Materials- like iron ore
fines, iron bearing waste products, flue dust, Steel plantreverts.
It can be produced into any shapes and sizes. It can be cured to adequate strength suiting Blast
Furnace needs.
Process designed to suitable small batch operations andlarge scale operations.
Excellent blast Furnace charge material in place oflump ore, reduces the cost of smelting of ore, increasesFurnace permeability there by increasing BFproductivity and lowering cost in terms of lower fuelrate.
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WHAT IS SINTER
Sintering is the process of agglomeration of
iron ore fines into a porous mass by
incipient fusion heat generated within themass itself.
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TYPES OF SINTER
Depending upon weather bases have been incorporated in the Sinter mix,sinters are divided into three broad classes: -
(i) Non Fluxed OR ACID SINTERS: - Those where no flux is present or isadded in the ore.
(ii) BASIC SINTER OR Self Fluxing SINTER: - Those where sufficientflux has been added in the sinter mix to provide a basicity that is desiredin the final slag, taking into consideration only the burden acids. An extraflux is added to the BF burden, to take care of coke ash acids.
(iii) SUPER BASIC OR SUPER FLUXED SINTER: - In these type of
sinters an additional flux is added to the mix to provide for the desiredfinal slag basicity, taking into account the acids content of both ore as wellas the coke ash.
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THE NEED FOR SINTER
(i) To utilize the fines generated during the miningoperation.
(ii) To utilize different additives like mill scale, fluedust, hearth slag etc. in an integrated steel plant.
(iii) The need for charging prepared burden in Blast
Furnaces to increase productivity and lower fuel rate.
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ADVANTAGE OF SINTER i) Agglomeration of fines into hard, strong and irregular porous lumps which givesbetter bed permeability.
ii) Elimination of 60 - 70 % of sulphur and Arsenic (if present) during sintering.
iii) Elimination of moisture, hydrated water and other volatiles on the sinter strand witha cheaper fuel.
iv) Increased the softening temperature and narrowing down of the softening range.
v) As the calculation of flux takes place in sinter strand, super-fluxing saves much morecoke in the furnace.
vi) It increases the Blast Furnace productivity.
vii) Lime rich bosh slag hinders reduction of silica, absorbs vaporized silicon and
sulphur to produce low- Si, low-S iron.
viii) Increase of sinter percentage in Blast Furnace burden, increases the permeability,hence reduction and heating rate or burden increases, so the productivity also.
ix) Utilization of solid wastes generate within steel works
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TYPES OF SINTER MAKING
PROCESS Huntington and
Heberlein Pot Process-fpr non-Ferrous metal
Industry. Batch Sintering-
Greenwalt Single PanProcess
Allmanns IngenoirsBryans Multi PanProcess
Dwight-LloydContinuous SinteringProcess
Pelletizing Process- Thisconsists of suboperations likepreparation of ore feed,balling, hardening. Shaft
furnaces are used forproducing smalltonnages. MultipleShafts handle largerproduction level.
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23Huntington & Heberlein Blast roasting Pot Vacuum Extrusion Process
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24Green walt Single Pan Sinter Machine Pelletizing Process
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PRINCIPLE OF THE SINTER
MAKING PROCESS Iron one sintering is carried out by putting GREEN MIX after Mixing and Nodulizing drum (a
mixture of Base mode with iron ore fines, mixed with flux, coke breeze as a solid fuel, otheradditions, sinter return fines, lime, moisture) over a traveling gate in form of permeable bedand permeable bed.
The top layer of this sinter bed is heated to the sintering temp. (1200C-1300C) inside a Ignition
Hood furnace. In the ignition hood the air is drawn downwards, through the grate with the helpof exhaust blowers (Waste Gas Fan) connected by means of Waste gas main.
The narrow combustion zone developed initially at the top layer by layer to the sintering level.The cold blast drawn through the bed cools the already sintered layer the thereby gets itselfheated. The heat contained in the blast is utilized in drying and preheating the lower layers inthe bed. In advance of combustion therefore each layer gets dried and preheated by the heattransferred from the upper combustion zones. The lower portion of the bed absorbs much ofthe heat in the gases.
In the combustion zone, bonding takes place between the grains and a strong and porousaggregate is formed. The process is over when the combustion zone has reached the lowestlayer of the bed. The sinter cake is thus tipped from the grate in hot condition . It is thenbroken, cooled in sinter cooler cold sized and sent to the Blast furnace.
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MECHANISM OF SINTERING
2Fe2O3.CaO + Al2O3.SiO2 2Fe2O3 CaO.Al2O3.SiO2
(SFCA)
SILICO FERRITE OF CALCIUM
AND ALUMINIUM
2Fe2O3
SLAG BOND
2Fe2O3
2Fe2O3
Heating Cooling
Singlelump
Heating2Fe2O3
2Fe2O3
+ CaO 2Fe2O3CaO at 12000CCALCIUM FERRITE
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GENERAL ARRANGEMENT OF
A SINTER PLANT Raw material receiving and
proportioning system
Mixing and Nodulizing-moisture addition
Charging Station-laying ofGreen mix on the strand
Ignition
Sintering Process
Sinter Discharging and Hotbreaking
Cooling of sinter in SinterCooler
Treatment of Sinter in termsof Cold crushing and sizing.
Conveying to BF stock-house
Dust treatment and Waste
Gas system with Waste GasFan and De-dusting Fan
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EQUIPMENTS IN SINTER
PLANTS RAW MATERIAL BINS AND
WEIGH FEEDERS
MIXING AND NODULIZINGDRUM WITH WATERINJECTION SYSTEM
SURGE BIN-SECTOR GATESWITH SERVO DRIVES ANDFEED DRUM
IGNITION HOOD FURNACEWITH BURNERS
SINTER MACHINE-PALLETS
with GRATE BARS WINDBOXES WITH WASTE
GAS MAIN
SPIKE CRUSHER-WITHCRASH DECK
DOUBLE ROLL CRUSHER
VIBRATORY COLD SCREENFOR HEARTH LAYER
VIBRATORY SCREEN FORRETURN FINES
CONVEYORS, RECEIVINGCHUTES AND TRANSFERCHUTES FOR RAWMATERIAL AND SINTER
WASTE GAS FAN WITH LCIDRIVE
DEDUSTING FAN FOR PLANT
DEDUSTING ESPs
LT and HT DRIVES
PNUEMATIC ACTUATORS &VALVES
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SINTER PLANT FACILITIES AT
TATA STEEL
F:\Sinter Plant Facilities at Tata Steel.pdf
http://localhost/var/www/apps/conversion/Master/My%20Documents/SP-3%20Comm/Sinter%20Plant%20Facilities%20at%20Tata%20Steel.pdfhttp://localhost/var/www/apps/conversion/Master/My%20Documents/SP-3%20Comm/Sinter%20Plant%20Facilities%20at%20Tata%20Steel.pdfhttp://localhost/var/www/apps/conversion/Master/Sinter%20Plant%20Facilities%20at%20Tata%20Steel.pdfhttp://localhost/var/www/apps/conversion/Master/Sinter%20Plant%20Facilities%20at%20Tata%20Steel.pdfhttp://localhost/var/www/apps/conversion/Master/Sinter%20Plant%20Facilities%20at%20Tata%20Steel.pdfhttp://localhost/var/www/apps/conversion/Master/Sinter%20Plant%20Facilities%20at%20Tata%20Steel.pdfhttp://localhost/var/www/apps/conversion/Master/My%20Documents/SP-3%20Comm/Sinter%20Plant%20Facilities%20at%20Tata%20Steel.pdfhttp://localhost/var/www/apps/conversion/Master/My%20Documents/SP-3%20Comm/Sinter%20Plant%20Facilities%20at%20Tata%20Steel.pdfhttp://localhost/var/www/apps/conversion/Master/My%20Documents/SP-3%20Comm/Sinter%20Plant%20Facilities%20at%20Tata%20Steel.pdf8/12/2019 Sintering Plant at a Glance - Copy
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DIFFERENT UNITS OF SINTER PLANT
RAW MATERIAL BEDDING AND BLENDING PLANT
SINTER PLANT 1
SINTER PLANT 2
RAW MATERIAL BEDDING AND BLENDING ( NEW )
SINTER PLANT 3
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FUNCTIONS OF RMBB
Stacking of Raw materials
Bedding and Blending of various rawmaterials and other constituents of Sintermix through proportioning
Homogenizing the mix components forachieving consistent Sinter chemistry
R M B B PLANT LAYOUT
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R.M.B.B.PLANT LAYOUT
WAGO
NT/H
C/S
TGH
P
R
O
P
B
U
I
L
D
I
N
G
ROD MILLS
CRUSHER
H/M
COKE SCREEN
FLUX
SCEEN
WOB#2
WOB#1
TBS#1
TBS#2
SP1/SP2
B/R (L&T)
B/R
(ELECON)
P
Y
RD
U
N
Ld
Slg.
Ret. Sinter fines From G.Fce.
I
O
F
LS
F
R
P
D
F
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Material Flow at Sinter Plant
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Hot Return
Fines
Hearth
Layer
SINTER
STORAGE
Sinter
Screening
Proportioning
Bins
Mixer
Water
Sinter
Machine
Sinter
Cooler
Waste Gas
Fan Waste Gas
Esp.
BF HIGH
LINE
Raw
MaterialsReturn Fines Lime
Dust
Hearth
Layer
Hot Air
Combustion Air
Cold Return
Fines
Ignition Hood
Spike
CrusherCooler Fan
Segregati
on
Chute
Doubl
eRoll
Crusher
Cold
screen
SINTER PLANT
OVER VIEW OF SP#3-a typical DWL Sinter
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OVER VIEW OF SP#3-a typical DWL Sinter
Machine
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FEDDING SYSTEM
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BED
HEIGHT
LEVEL SENSOR
FLAPGATES
IGNITION
HOOD
FEED ROLL
HEARTH LAYER
GREEN-MIX
BIN
GREEN MIX
SHUTTLE CONVEYOR
THERMO-VISION
CAMERA
PROBES
HEAT TREAT
MENT HOOD
HEARTH
LAYER
BIN
CUT-OFF
PLATE
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QUALITY ASPECT OF SINTER-
WITH RESPECT TO BLAST
FURNACES PERFORMANCE CHEMICAL
1. Fe% in Sinter
2. CaO % in Sinter
3. SiO2 % in Sinter
4. MgO% in Sinter
5. Al2O3 % in Sinter
6. FeO % in Sinter
7. K2O % in Sinter
PHYSICAL
1. SINTER SIZEANALYSIS in terms ofCum+10mm and -5mm
2. TUMBLER INDEX
3. SHATTER INDEX
4. RDI (ReducibilityDegradation Index)
5. RI (Reducibility Index)
6. Softening and MeltingTest (S-M)
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FACTORS AFFECTING SINTER
QUALITY
(1) Size of The Charge Mix: The strength of sinter is directly related to the sizedistribution of the charge mix. If size is large, the contact area will be less and thestrength of the sinter will be low and conversely if size is too small the contact area ofparticles will be large and the strength will be high.
Ideal size of ore Fines -10 mm to + 100 meshCoke breeze -3.2 mm 85%Flux - - 3.2 mm 85%
(2) Fuel content: - Variation in Fuel content in Charge Mix affect the peak Temperatureattained during sintering, the combustion zone will not be uniform leading to poor bedpermeability, This increases return fines generation
(3) Moisture: - The presence of moisture in the Charge mix has several advantages. Itmaintains proper permeability in the bed during sintering. This is beneficial from thepoint of view of heat transfer during sintering.
(4) Re-circulating load or Return fines addition:- For higher output of the sinter strandthe circulating load should be low. A low circulating load however, reduces thepermeability of the bed. An optimum-circulating load is established for maximumoutput of the acceptable sinter to the Blast Furnaces.
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Parameters Controlling Sintering
Process Fuel content for heat input
Ignition intensity-Temperature of Ignition
Hood Furnace
Moisture content of mix tocontrol its permeability.
Machine speed control to
obtain complete Burnthrough
Return Fines Addition
Waste Gas Temperature
Sintering Temperature orBurn through Temperature
Pressure drop across theSinter Bed- Main Suction
Bed Height
Calcined Lime addition- toimprove bed Permeability.
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IMPROVEMENT IN PERFORMANCE OF
SINTER PLANTS
BYINTENSIFICATION OF SINTERING
PROCESS
By
Dr M T Raju
Deputy General ManagerRDCIS
SAIL
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Managing the existing technologies to reach
designed/rated performance
Incorporation of innovations to surpass rated
capacity
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Reaching rated capacity:
1. MEN (WOMEN)
2. MATERIAL3. MONEY
4. MINUTES
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Surpassing rated capacity:
Creative (Innovative) solutions can only
enable to surpass.Five elements of creativity.
1. FLUENCY
2. FLEXIBILITY
3. ORIGINALITY
4. AWARENESS
5. DRIVE
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INTENSIFICATION OF SINTERING
PROCESS
Sinter as a prepared burden material
continues to hold its prominent position in
world due to its very good metallurgicalproperties such as tumbling strength,
reduction degradation index, reducibility
index, high softening temperature and low
range of softening range
PRINCIPAL STEPS OF IRON ORE
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PRINCIPAL STEPS OF IRON ORE
SINTERING TECHNOLOGY The iron ore fines , lime stone fines, dolomite
fines, lime dust, metallurgical wastes and cokebreeze are proportioned based on charge
calculations.
Then this mix is mixed and balled in mixing and
balling drums with the addition of water and thenloaded onto the pallet.
The sinter mix undergoes ignition as well as
suction is applied under the bed.
The top layer gets ignited and sintering proceeds
down wards till the end .
The hot sinter is screened and crushed.
The hot sinter is then cooled on a cooler
The cooled sinter is screened to remove -5mm
fraction and then transported to blast furnace.
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Need of Intensification of
sintering process
Why?
Intensification of sintering process is required
to enhance the production capacity of existingsinter machines.
How?
Without sacrificing the quality aspects.
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What is meant by intensification?
Accelerating sintering process for achieving higherproduction without deterioration in quality.
Production = k*A*B*V*Yk = Constant
A = Sintering Area
B = Bulk Density of mix
V = Vertical sintering speedY = Yield
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Methodology of Intensification of
sintering process
Factors that influence sintering
1) MEN2) MATERIALS
3) PROCESS PARAMETERS.
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MATERIALS1) Iron ore fines size
2) Iron ore fines chemistry
3) Coke breeze
4) Calcined Lime
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.
The granulometry of iron ore fines, used in
sintering, has a great influence on sinter plant
performance.
Laboratory Experiments were conducted withdifferent granulometry of iron ore fines to assess its
influence on sinter quality and productivity.
The upper size of the iron ore fines was reduced ineach of the experiments.
GRANULOMETRY OF IRON ORE FINES
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EFFECT OF IRON ORE FINES SIZE ON
SINTERING
Sl.No Size Lime %yield VSS Prod. T.I(mm) (Kg/t) (+5mm) mm/min t/m2/h %
1 0-15 0.0 70.6 18.6 1.182 69.3
2 0-8 0.0 76.5 19.6 1.272 68.3
3 0-8 20.0 75.6 20.1 1.326 67.2
4 0-6 20.0 80.3 20.3 1.418 67.3
5 0-5 20.0 81.0 21.6 1.489 66.7
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Chemical Quality
EFFECT OF TOTAL Fe
Results show that lower Fe grade (< 62% Fe) ores and
concentrates will typically form SFCA (SiO2-Fe2O3-
CaO-Al2O3) as part of the final assemblage.
Medium grade (62-65% Fe) ores will form a mixture of
SFCA and SFCA-1..
High grade (65-68% Fe) ores will form largely SFCA-1.
The SFCA-1 phase is the most desirable bonding phase in
iron ore sinter, since microstructures composed entirely ofSFCA-1 show higher physical strength and higher
reducibility than microstructures composed predominantly
of SFCA
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LOSS ON IGNITION
The higher LOI of iron ore fines has a detrimental
effect on sinter quality and productivity
EFFECT OF Al2O3
An increase in Al2O3 % by 1 % increases the RDI
value by 10%
EFFECT OF SiO2
Higher SiO2 in sinter will induce the formation of
glassy phases in sinter and reduce the strength ofsinter.
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COKE BREEZE SIZE
The required coke breeze granulometry for
efficient sintering is:
+5 mm < 5 %
- 3 mm = 85-90 %
-0.5 mm < 15 %
Presence of higher % of +5 mm slows down the
coke breeze burning rate and thus reducing
sintering rate.
For reducing the micro-fines generation during
crushing, -3 mm should be screened out before
the crusher.
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PROCESS PARAMETERS
Mixing and Balling
Segregation of mix
Moisture
Ignition
Under-grate Suction
Preheating of sinter mix
Use of hot air in ignition hood
cooling
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MIXING AND BALLING REGIMES
Generally most of the sinter plants are provided
with separate mixing and balling drums. But the
latest generation of sinter plants are provided with
a combined mixing and balling drums.
The main purpose of mixing drum is to
homogenize the sinter mix . The diameter of the
drum , the RPM and the space factor play a major
role in achieving higher degree of mixing.
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The balling drum (Nodulising drum) ensures that
fines are coated on the nuclei particles, thus
produce higher size balls. This facilitates in
improving the mean size of sinter mix and hencethe permeability of mix. Here again the diameter ,
RPM and space factor play a major role in
achieving higher degree of balling.
Very little water is added in mixing drum and
major quantity of water is added in the balling
drum
The amount of water added and the method ofwater addition in the balling drum also control the
degree of balling and hence the permeability of
sinter mix.
Laboratory model of high speed agitating mixer
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A
Laboratory model of high speed agitating mixer
Lab study at RDCIS showed improvement of strength
index with reference to conventional mixer
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MOISTURE
As is known, faster the rate of air flow through
the bed faster is the rate of sintering.
The rate of flow of the air through the bed is
controlled by the vacuum under the bed and the
permeability of the bed.
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SUCTION UNDER-GRATE
The rate of flow of the air through the bed is
controlled by the vacuum under the bed and the
permeability of the bed.
The optimization of the gas dynamics parameters of
the sinter machines enables one to achieve higher
under grate suction and thus substantial
improvements in the techno-economic parameters ofthe sinter production.
IMPROVING IN SM PRODUCTVITY PER 10 AS
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IMPROVING IN SM PRODUCTVITY PER 10 mmwc AS
A FUNCTION OF SUCTION UNDER GRATE
500 600 700 800 900 1000 110 1200 1300 1400 1500
1.2
1.0
0.8
0.6
0.4
SUCTION, mmwc
IN
CR
E
A
SI
N
G
IN
P
R
O
D
U
C
TI
VIT
Y,
%
IGNITION
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IGNITION
To provide the required free oxygen potential in thezones for faster burning of the fuel and also early
starting of sintering.
Oxygen enrichment in ignition hood
To produce a strong sinter in the upper part of the
layer;
PRE HEATING OF SINTER MIX
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PRE-HEATING OF SINTER MIX
Pre-heating of sinter mix helps in reducing the ill effects
of Re-condensation of moisture
Pre-heating of sinter mix can be done by:
* Addition of hot water in balling drum* Addition of steam in balling drum or raw mix hopper
* Installing gas burners inside the balling drum
* Adding hot return fines
* Addition of calcined lime
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HOT AIR IN IGNITION HOOD
Hot air recovered from sinter cooler could be used in
the ignition hood.
This will help in not only saving gaseous fuel, but alsoincreases the free oxygen potential.
COOLING OF SINTER
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COOLING OF SINTER
Efficient cooling of sinter will help in improving sinterstrength
Installation of proper waste heat recovery system of
cooler will help in adding hot air in ignition hood
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Rate
Size
BTP
Temp
Sinter Quality
Temp
Free O2
Potential
Top layer
Starting of
sintering
Productivity
Rate
Method of
Addition
Balling
Permeability
Re-condensation
Under
Ignition hood
Rest of
machine
Coke
Water
Under grate
suction
Ignition
RECENT TRENDS OF INTENSIFICATION OF
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RECENT TRENDS OF INTENSIFICATION OF
SINTERING
High Fe, low Al2O3iron ore fines Serpentine replacing dolomite
Good quality and quantity of lime addition
High Intensity mixer
Divided coke addition Polymer addition in balling drum
Pre-heating of sinter mix
New sinter mix charging system
New ignition furnaces
Taller bed operation Higher under grate suction
Taller bed circular coolers
Process control models
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