Now a days about 60% of iron ore converted to fines during mining, handling and transporting so pellet is a process of utilizing iron ore fines up to size of 0.15 microns. i investigate its process,equipment used in process, wear and other problems in them and its future scope
Pelletization of iron ores and the type of wear liners used in thier eqipments
1. BY; Gulshan kumar singh
VT20161710
Mechanical engineering
SS College Of Engineering
Udaipur,Rajasthan
Guided by: Dr. Anand prabhakaran.
IRON ORE PELLETPLANT;
PROCESS & WEAR MAPPING AT TATA steel
2. TATA STEEL
Overview
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▫Established in 1907,Asia’s first and India,s largest private sector steel company.
▫World’s 6th largest steel company with manufacturing units in 26 countries.
▫Existing crude steel production capacity is 30MTPA.
▫Tata steel jamshedpur alone has crude steel production capacity of 8.8 MTPA which will said
to increase to 10 MTPA by 2020.
▫It,s community outreach programmes covers Tata steel managed city of Jamshedpur and
over 600 villages in and around.
3. What is
pellet ?
The “pellets” or “Iron ore pellets” is actually a
spherical uniform form of iron ore fines mixed
with some ingredients like Dolomite, Bentonite,
limestone and coke breeze which are later
introduce in a furnace to get high quality iron or
steel later.
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Coal fines/coke
Iron ore fines
Bentonite
Pellets
4. Need of
pelletizing of Iron
ores
▫Configuration of Iron ore fines as tightly packed
structure that restricts heat and air flow in blast
furnace.
▫Utilization of iron ore fines of size even 0.5-0.15mm.
▫Extending the life of iron ore reserves of nation.
▫To improve Blast furnace performance
Increase in blast furnace productivity.
Decrease in uses of blast furnace fuel/coke fuel.
Improve in quality of hot metal.
Decrease in slag rate.
5. Product pellet
screening
Despatch to Blast
furnace
Raw material storage
bins
Drying Disc pelletizing
Grinding Mixing
Ground concentrate
storage bins
Air classification
Induration
Lime stone
Iron ore fines
coal
Crushing
Bentonite Water
Olivine
FLOW PROCESS IN TATA STEEL PELLET PLANT5
7. A. Raw material recieving circuit;
Blended Iron fines from Noamundi jharkhand is brought into trucks and fed
into 4 Iron ore Bins/hoppers.
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stage1;Raw material preparation
8. Dolomite; Dolomite or limestone is used to tailor the chemistry of pellets and
to produce fired pellets with desired chemical and physical properties.
Dolomite/limestone are used to remove sulphur, phosphorous and other
unwantedimpurities from Iron ore fines.
Coke/coal; It is simply a solid fuel added to pellets to improve the furnace
productivity and overall fuel economy..
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B. Receiving of Coal and Limestone and crushing circuit
9. 9
Raw material
section
IOF BINS
Capacity-2125tonn
Volume- 850 m3 each
Bulk density-2.5tonn/m3
Material size- <80mm
FLUX BIN
Capacity-320tonn
Volume- 200m3
Bulk density- 1.6tonn/m3
Material size-< 40mm
COAL BIN
Capacity- 160tonn
Volume- 200m3
Bulk density-0.8tonn/m3
Material size-< 40mm
Conveyer
11. 11
GRINDING
CIRCUIT
Ball mills are used for grinding of ores and additives.
Iron ores and additive ground to size of minus 45 microns.
•TATA steel opt for DRY GRINDING
presence of high alumina content can leads to sluggish filtration in Wet grinding.
+ Ores along with additives can ground together, unlike wet grinding.
12. BALL MILL12
Type- Dry grinding
Size- Ø 6.096 m x 12.2 m long
Mill drive power- 2x5000kW
Mill speed- 8.68 to 13.19
Balls Loading-(% of Mil lVolume)
20% to 35%
Liners - Hi-Chrome
Material handle -iron ore
Mass flow rate- 433.5TPH dry
solids
Product sizeP80 = -50 microns
Feed head
shell Discharge
head
13. stage2. Green pellet formation
Mixing circuit
Ground ores is mixed with BENTONITE 0.4% (binder) with approx 9% moisture.
Bentonite is the binder holds the particles in the agglomerates to convert it into pellets.
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16. ▫Seven zones
1.Updraft drying UDD
2.Downdraft drying DDD
3.Preheating
4.Firing
5.After firing
6.Primary Cooling
7.Secondary cooling
Heat from secondary cooling
zone is supplied to updraft drying
zone.
Heat from firing zone is
supplied to downdraft drying
▫
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18. Concept of wear
“Removal or displacement of materials from one body when subjected in contact
with other body or having relative motion with other body.”
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1.Adhesive wear
(Galling, scuffing)
2. Abrasive wear
(scratching of harder
material on softer)
3. Fretting wear
(fretting corrosion)
4. Erosive wear
(cavitations)
5. Rolling wear
6. Fatigue wear
19. Wear mapping
of major
components of
pellet plant
▫Iron ore & raw materials
bins/hoppers
▫Conveyer chutes
▫Drier (rotary kiln)
▫Ball mills
▫Bins & mixer (mixing sec.)
▫Pelletizing discs
▫Plough scrappers
▫Induration sec. Fans
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20. ▫Wear can reduce the life
of components .
▫It can cause sudden
downtime in plant.
▫Can decrease
productivity.
▫It may lead to failure of
equipments
▫LINERS are the material made up of
composition of alumina, sillicon
,mangnese, carbides etc that is used to
bolt on the wear prone surface of
equipments.
▫Some of most common liners used
▫ Polymer liner
▫ Arcoplate liner
▫ Ceramic liner
▫ Hardox liner
▫ PU (Poly-Urethane) liner
▫ High-Chrome liner plate
▫ Rubber liner etc.
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Losses due to wear
Wear liners
To prevent wear loss
Wear liners are used
21. Wear prone areas in Bins and hoppers:
▫1. screening/Grating- deals with the
screening of unwanted hard rocks and other
scraps. Hence wear occurs at grating.
▫2.Silo/Bins section- deals with the flow
resistance of coarse ores and additives.
Abrasion wear occurs.
▫3. Hopper- Here VolumeV1>V2
Means more amount of coarse ores passes
through lesser volume. It’s one of most
wear prone areas of RMS.
▫4.Chutes- since they receives the raw
materials from hopper thus subject to high
impact load.21
22. 22
Silo/Bin
UHMWPE high abrasion
polymer liner
Size-1000X750X20
20mm thick
COF-0.08
Life-8 months to 1 yr.
Provides good flow
ability
Bottom mouth
piece/hopper
LINER ACROPLATE
7mm
Life-3 yrs.
Conveyer Chutes
ESAB CHROME-C
16mm thick (10mm
base plate+6mm
carbide coating)
Life-1year 6 to 8
months approx
Liners in raw material bins/hoppers.
Grating or screening
ACROPLATE liner
with high chrome-
40%
Size-
2340mmX1060mmX1
10mm
15mm thick
Life- 1 year
23. Various types of liners used in Ball mill
Feed head liner
Life- 1 and ½ year.
4 rows of liner is employed
Shell liner
ASTMA36 liner
50-70 mm thick
Life - > 3years.
0.01% max. sulphur
48 rows and 60 columns
Discharge head liner
Life- 10 months- 1year
24. Inside Ball mill (LINERS)
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Discharge feed liner
Shell liner
Ball grinding media
Feed head liner
25. Liners used in Drier
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32m
6m dia.
HARDOX LINER
1. SHELL LINER (1 ROW)
2. SPIRAL LINER (2 ROW)
3. LIFTER LINER (3 ROW AT 45°)
4. LIFTER LINER (4 ROWS AT 60°)
4°inclined
Liners inside drier
26. Wear mapping of pelletizing disc
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This area is continuously in contact
with the radically outwards moving
green pellets. This can reduce life of
disc.
Discharge chute
This is used to discharge the green
pellets to bins and hence always in
contact with pellets. This is a wear
prone area too.
Pelletizing disc deals with the
green pellets having low strength
Hence low impact and low wear.
The life of liners used are greater
here.
27. Liners used in pelletizing Disc
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Ultra High Molecular Weight
Poly-Urethane liner
•Highly abrasion resistant
•Low COF
•Offers good flow-ability and jamming
patterns
•Mostly used in lining of curved
surfaces.
•Good for sticky abrasive materials
•Life-( in trial presently.)
PU liner
28. Induration fans- wear mapping ▫Cooling fan- sucks the
ambient air from atmosphere
and provide to cooling zone.
▫Recuperation fan- Sucks the
hot air from firing zone and
supply to downdraft zone
▫It is subject to dust load and
heat impact, hence most wear
prone part.
▫UDD fan- sucks heat from
cooling zone to supply to UDD
zone.
▫Second most wear prone area.
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29. Liners in Fans
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Arcohardox liner is
used in casing of all
process fans.
12 mm thickness
Life - >5 years.
Tungsten Carbide layer is put on by
welding on
*Tip
*mating of shroud and vanes
*Nose
They are subject to dust load and heat as
dust used to rub at tip and nose of fan.
Nose
shroud
vanes
Tungsten carbide layer
30. Histogram showing lives of liner
30 0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
IOB silos
IOB hopper
Conveyerchutes
screening
fan casing
fan nose tip
ballmill shel
discharge head
Life of liners used
in IOB silos
,hoppers and
discharge head is
lesser
Ball mill
discharge
head life
31. Cause and effect diagram for lesser life of silos liners
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Abrasion wear High impact load
Unwanted
materials and
scraps
Wear of Grate
Lesser liner life
of RMS
equipments
Deals with coarse Weigh of RMSize of
RM
High harder
unwanted material
content
32. Recommendation
▫Presently used liner
▫POLYMER LINER
▫Cost– less
▫Life- 1year
▫Liner bolting labor
charge- same
▫Downtime- 3 times in
2yrs
▫Total cost- equal or
greater
Recommended for trial
▫POLY-SILI LINER
▫Cost- more
▫Life- 2year
▫Same labor charge
▫Downtime- 1 time in 2
years
▫Total cost-equal or
lesser
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Recommended
Benefits; less downtime hence greater production
Relief from complex process of employing liner number of times
lesser maintainenace inspection.
33. CREDITS Nirmal B kumar (SSTG)
Panchanand Panda (GPV, pellet
plant)
Kanhaiya singh(RMS, pellet plant)
Mohzarul Haq (Drier, pellet plant)
K sundar rao(Ballmill, pellet plant)
All staffs of TATA steel pellet plant who took
the pain of my so many questions and provide
details inspite of their hectic routine.33
34. THANKS Any questions?
You can find me at
▫ gulshangaurav221@gmai.com
▫ Linkedin
@gulshangaurav221@gmail.com
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