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Background• Incoming iron ore fines of JSW are of wide variation in physical and chemical properties.
• The higher gangue content (Al2O3+SiO2) and the ultra fines (<150 micron)
are detrimental to agglomeration process.
• Low grade iron ore fines beneficiation to get the consistency w.r.t physical & chemical properties of iron ore fines
after mining ban at Karnataka.
• Usage of high manganese iron ore fines at Agglomeration and its impact in steel making.
• Blast furnace performance with respect to 90 percent agglomerate burden.
• Waste handling through micro pellet plant for efficient utilization in base mix.
• Usage of recovered slime through slime recovery plant in pellet making.
Source –wise Iron Ore Chemistry-Low & Medium Grade
Low Grade IOF
Medium Grade IOF
Wide variation in Chemistry
Jig and Spiral Performance
Particle size distributionJigs & Spirals
feedJigs & Spirals Conc.
Medium
grade IOF
(+1)mm 59.07 69.93
(-150) mic 9.61 5.13
Low grade
IOF
(+1)mm 59.61 60.74
(-150) mic 7.77 6.66
Medium grade IOF Low grade IOF
Jigs &
Spirals
feed
Jigs &
Spirals
Conc.
% up-gradation
Jigs &
Spirals
feed
Jigs & Spirals
Conc.% up-gradation
Fe(T) 58.59 59.34 1.28 55.73 57.89 3.88
SiO2 4.92 4.16 15.45 8.55 6.39 25.26
Al2O3 5.33 5.01 6.00 5.99 5.13 14.36
LOI 5.1 5.1 _ 5.13 4.77 7.02
Improved up-gradation in case of low grade IOF with respect SiO2 and Al2O3
Comparative Analysis- Low and Medium Grade IOF
Low Grade Medium Grade
Feed Fe 48.90 52.69
Feed SiO2 12.80 9.46
Feed Al2O3 9.76 8.21
Sinter Product Fe 57.89 59.34
Sinter Product SiO2 6.39 4.16
Sinter Product Al2O3 5.13 5.01
Pellet Product Fe 56.28 60.91
Pellet Product SiO2 10.32 5.24
Pellet Product Al2O3 4.86 3.78
Tails Fe 34.93 37.82
Improved Product grade up-gradation in case of Medium Grade Processing
Comparable product grade up-gradation of sinter fines in both cases
Raw Material Challenges in Agglomeration
• Bellary and Hospet Iron ore fines are
soft and flaky in nature with high
content of Al2O3 and SiO2
• High Super fines (<100 mesh) percentage
•Low Tumbler and flaky nature of local
lump ore is detrimental to high
productive BF.
• To minimize the lump ore dependency,
about 90 % of BF burden as
agglomerate
Impact of Calcined Lime addition in Sinter Making
Sinter productivity improves with ground Calcined lime addition (<75 micron) due to
better Quasi particle strength and Granulation of sinter green mix.
Sinter Chemistry Management at JSW
• Usage of 10 to 15 percent beneficiated sinter product in base mix preparation, lower the gangue content and
minimizes the ill effect of ultra fines (<100 mesh %)
• Usage of imported limestone and dolomite reduces the gangue content in sinter and Alkali Input to BF
• Usage of Anthracite coal as a solid fuel reduces the VM (<4, %)
• Usage of High Manganese iron ore fines in base mix blend which contain low alumina, reduces alumina in sinter
Anthracite Coal addition VS Solid Fuel VM
ESP performance improves with reduced VM in solid fuel after blending with Anthracite
Impact of High MnO IOF Usage in Sintering
• High MnO IOF reduces the sinter alumina from 5.23
% to 4.85 %
• Low alumina sinter reduces the BF slag rate from 571
Kg/thm to 544 kg/thm
• High MnO percent in sinter along with high alumina
reduces the sinter Tumbler by Index by 2.09 percent
Impact of Secondary Nodulizer in Sinter Making
• Improved Granulation during secondary Nodulizer operation leads to High Productivity with low Fan RPM
• Lower Fan RPM helps in reducing the power consumption
• Improved BTP help in achieving better sinter quality w.r.to Tumbler Index and MPS
Impact of Green Mix Carbon Percentage on Pellet Making
Green Mix
Carbon%
ranges
Green Mix
carbon,%CCS
Tumbler
Index
Abrasion
IndexRDI RDI
Unfired
%(+6.3mm)% (0.5mm)% (6.3mm)% (0.5mm)%
0.80-0.90 0.86 235 93.52 5.52 17 14 7.79
0.90-0.95 0.93 233 93.44 5.63 16 14 7.8
0.95-1.00 0.98 236 93.95 5.14 14 10 6.38
1.00-1.05 1.03 238 94.51 4.55 12 8 5.65
1.05-1.10 1.08 248 94.80 4.30 11 7 5.33
1.10-1.15 1.13 251 95.06 4.07 11 7 5.36
1.15-1.20 1.17 237 94.54 4.33 11 7 5.61
1.20-1.25 1.22 241 94.68 4.34 10 7 5.66
1.25-1.30 1.26 243 94.79 4.16 11 7 5.51
>1.30 1.38 245 94.28 4.84 12 8 5.68
1.10 to 1.15 percent green mix carbon is optimum for better pellet properties
Impact of < 45 micron Grain Size on Pellet Properties
Pellet
PropertiesUnit
Increase in (<45) mic,% in Pellet Concentrate
<55% 55-60% 60-65% 65-70% >70%
AI (-0.5mm) % 7.50 7.30 6.00 5.50 4.10
TI (+6.3mm) % 91.50 91.60 93.00 93.50 95.30
CCS Kg/pellet 216 222 235 240 283
RDI (-6.3mm) % 11.30 11.50 10.20 10.20 10.60
RDI (-0.5mm) % 7.80 8.00 6.50 6.50 3.30
RDI (-3.15mm) % 6.50 6.80 6.80 6.90 4.00
Pellet Properties significantly improves w.r.to CCS, TI and RDI
with increase of <45 micron percentage in pellet concentrate
Waste Material in Integrated Steel Plant
Unit Process By-productCalcination plant Lime fines, semi-calcined lime, lime stone undersize
Refractories plant Refractories waste
Sinter plant Electro-filter dust, air borne dust
Coke Ovens Coke breeze, coke oven gas
Pellet plant Pelletization slurry
Blast furnaces B F gas, top gas dust & sludge, cast house & bunker house dedusting,
and slag granulate
Corex Corex sludge, slag
H M desulphurisation Slag, dust
BOF steelmaking L D gas, slag, sludge, primary & secondary dedusting dust, vessel
slopping
Secondary steelmaking Slag, dust
Rolling mill Mill scale
Recycling of waste material is best method to protect Environment
which leads to cost reduction also
Waste Recycling Management at JSW
Three Major initiatives developed to utilize waste generation
Micro Pelletizing Plant Slime Recovery Plant Briquetting Plant
It process all dry waste like Bag
Filter dust, LCP dust etc in
desired proportion to meet the
base mix quality requirement
It process old dumped tailing
from tailing pond to get desired
product for pellet making.
•Reduction Specific IOF and
flux consumption at sinter plant
•Low sinter cost
•Input 46-48 % Fe upgrade to 56-
57 % Fe
•Low pellet cost
Mill scale Briquetting
• It is used in SMS as Coolant
• Low steel cost
Impact of Micro Pelletisation on Waste Consumption
Before Micro
Pellet
After Micro
Pellet
Metallurgical Waste Consumption increased from 50 kg/tons to 70 kg/tons
Major Innovative Initiative at Coke Oven
1) Usage of petroleum coke as an additives in coal blend to produce desired quality metallurgical coke
a) It helps in decreasing the coke ash by 17 percent and subsequently BF coke rate to the extent of
14kg/thm
2) Installation of Coke Dry Quenching system-Following advantage are depicted below
a) Conserve heat energy and water resources
b) Water pollution minimization in compare to Conventional quenching method
c) Reduction In CO emission.
d) Power Generation
e) Significant reduction in solid fuel consumption at Iron Making due to coke reduced and consistent
moisture compare to conventional method
Impact of Coke Moisture on BF Fuel Rate
Significant reduction in fuel rate in BF with reduced sp. Moisture input through coke
Technical Specification-Iron Making
Parameters Units CX#1 CX#2 BF#1 BF#2 BF#3 BF#4
Date of Blow in 8th Aug-99 15-Apr-01 18-Aug-04 10-Aug-06 18th Feb-09 18th July-11
Production Capacity Mtpa 0.8 0.8 0.9 1.3 3.0 3.0
Avg. Production tpd 2000 2000 2800 3625 8600 8600
Productivity (WV) t/m3/day 2.5 2.3 2.5 2.5
Working Volume m3 1107 1462 3445 3445
Inner Volume m3 1250 1681 4019 4019
No of Tuyeres no 26 26 18 20 36 36
Hearth Diameter m 7.3 7.3 8 8.4 13.2 13.2
Tap holes no. 2 2 2 2 4 4
Hot Blast Temperature oC NA NA 1050 1200 1250 1250
Stoves no. NA NA 3 3 3+1 3+1
TRT Station MWh NA NA NA NA 12.5 12.5
Impact of Sinter Burden on BF Productivity
Significant improvement in BF productivity after Increased sinter percentage in Burden from 50 to 80 %
Impact of Productivity on BF Fuel Rate
Reduction in Fuel rate after improved productivity with increase of sinter percentage
in BF Burden
Impact of Tap Duration/day and Slag Ratio
Improved Casting Practices through optimization of Tap Hole Diameter, Slag Ratio and
Cast Duration through in-house developed ‘Casting Model’ and ‘Slag-Balance Model’
High Slag Rate Management at BF
Increased slag rate from 380 Kg/thm to 450-550 Kg/thm due to increased sp. Alumina from from 55 Kg/thm
to 80-120 Kg/thm
Following Methodologies were adopted to optimize the process with high Slag rate operation at BF3 & BF4
• Optimizing Sinter Chemistry to minimize Raw Flux addition at Blast Furnace
• Optimizing Slag Chemistry: Al2O3 - 19.5% max., MgO – 7.5 to 8.0%, B2 – 1.05
• Stabilizing Burden descent by taking corrective and preventive measures to control Channeling and
Irregular Burden Descent.
• Optimizing Burden Distribution and blowing parameters to take care of Flooding & Loading of slag in
lower part of the furnace
Innovation in Corex Units
• Optimization of Fix-Carbon/thm from 670 to 600 kg/thm through reduction in Sp.
Oxygen from 560 to 510 Nm3/thm
•Lump Coke replaced by Nut Coke in Corex with sustainable furnace stability
resulting in low hot metal cost.
• Reduction in Fuel Rates by introduction of additional Coal Drying facility.
• Enhancement of Melting Rate through usage of Sinter fines directly into the Melter
Gasifier to negate the limitations in Reduction Shaft.
• Control of tuyere burning by optimizing the Slag Chemistry
HMPT at JSW Vijayanagar Works
• In the present time most of the iron making units is characterized by high silicon and
phosphorous, due to poor raw material characteristics.
• Removal of these impurities increases the processing time at LD converter and ladle treatment
and No full scale hot metal pre-treatment have been proved economically successful.
• JSW Steel, Vijayanagar Works, has successfully introduced India’s first Hot Metal Pre-Treatment
(HMPT) facility.
• JSW envisaged the removal of silicon and phosphorous separately by injection of reagents, fluxes
and oxygen through two lances in the transfer ladle in a two step process.
De-Si and De-P De-S
HMPT at JSW Vijayanagar Works
Blast Furnace 2
Blast Furnace 1
COREX 2
COREX 1
De-Si
De-P
De-S
De-C
Composition Change
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0.8 1.3 1.8 2.3
Silic
on W
t%
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0.8 1.3 1.8 2.3
Silic
on W
t %
0.00
0.04
0.08
0.12
0.16
0.20
0.24
0.8 1.3 1.8 2.3
Phosphoro
us, W
t %
1st Stage De-Siliconisation 2nd Stage De-Siliconisation De-Phosphorisation
Average ∆Si = 0.2 %Average ∆P = 0.06 %
Average ∆Si = 0.4 %Average ∆P = 0 %
Average ∆Si = 0.8 %
Average ∆P = 0 %
Start End Start End Start End
• The acceptable level of drop in silicon and phosphorous levels have been optimized to keep the
treatment time minimum without affecting the temperature.
• These levels have helped in keeping the charged hot metal average silicon and phosphorous levels
lower and consistent to primary steel making.
Benefits of Pre-Treatment
• Reduction in converter tap to tap time
• Improvement in Steel Cleanliness
• Reduction in slag generation and increased recycling
Slag Splashing
Initial Refractory Thickness : 900 mm
Slag splashing is a process of coating of left over
slag on the refractory lining of the vessel
It cools, solidifies, and creates a solid layer of slag
that serves as a consumable refractory layer.
Process Optimization
Tap
Temperature
Slag Height
Initial Lance Ht Slag Characteristics
Splashing Pattern
Time of
Splashing
Innovations
Selective Splashing
To splash the areas of localized erosionTo increase the life of bottom plugs
Slag Mushrooming
• Structured methodologies has been successfully used to improve the
converter lining life.
• Slag conducive for effective coating is developed.
• Splashing parameters have been optimized.
• Innovative methods of slag mushrooming and selective splashing have been
initiated.
• Furnace availability has increased.
• Holds the national bench mark of 13771 heats
Results
LD Slag
• The use of blast furnace slag as a constituent of concrete, either as
an aggregate or as a cementing material, or both, is well known.
• LD slag due to its very non-uniform nature and metallic content it
was never successfully utilized in cement making.
• In recent years, processed steel slag has evolved as an alternative
construction aggregate for many specialized applications.
Iron & Steel Slag : Comparison
BF Slag
• Limestone is chemically converted in
high temperature processes (High CaO).
• Generation @ 350 kgs / tcs
• CaO – 33% ; SiO2 – 30%; FeO – 0.3%
• Low Free Lime Content
• Low iron oxide fraction
• Negligible metallic iron fraction
• Better hydraulic properties
• Granulated and used in Cement making
Steel Slag
• Limestone is chemically converted inhigh temperature processes (High CaO).
• Generation @ 200 kgs / tcs
• CaO – 45% ; SiO2 – 12%; FeO – 20%
• High Free Lime Content
• High iron oxide fraction
• High metallic iron fraction
• Poorer hydraulic properties
• Metallic part recycled; rest is dumped
LD Slag Granulation
• JSW Steel introduced India’s first LD Slag Granulation process for increasing there-cycling of LD Slag
• LD Slag Granulation involves sudden quenching, of the molten slag, leading todifferent contraction of metal and slag and results in good separation of metal andslag.
• Adequate granulation takes place and leads to good stability of the final slag.
• Process can be called as accelerated ageing process which reduces the free limecontent. Removal of free lime also confirms its volumetric stability.
• Because of rapid cooling it generates more glassy structure than the air cooled slag.
LD Slag Granulation
• Shape of the granulated slag sand is
similar to BF Slag.
• Microscopically also, BF and LD slags are
similar.
Use of Granulated LD Slag
• With the introduction of LD slag granulation, new avenues of its applications
have been identified through in-house trials and in collaboration with NCCBM
(National Council for Cement and Building Research).
• Extensive studies have been carried out at JSW confirmed following
applications.
• As Raw Material in Cement Manufacture (up to 4.25 %)
• As Performance Improver in cement making (up to 5 %)
• As Blending Materials in cement making (up to 40 %)
• As Replacement of Natural Sand in Cement Mortar (up to 100 %)
Mill Scale Briquettes
• All Integrated steel plants generate waste oxides such as mill scale, caster scale,
CRM dust, sludge, dust etc.
• There is also environmental pressure to adopt eco-friendly strategies to reduce,
recycle and re-use their wastes.
• One way is through improvements in technology, operational practices, or
adopt/develop clean processes, or processes that do not generate the same
amount of waste.
• Requires huge investments and large design changes.
• Present industrial focus is to convert the generated wastes to usable form and
re-cycle back in the present process route.
Mill Scale Briquettes
• JSW steel is the first plant in the country and one of the very few in the world
to adopt mill scale briquetting.
• Mill scale, caster scale, CRM dust and similar high iron containing wastes are
mixed and briquetted.
• Presently mill scale briquettes are being used in both the steel making shops as
secondary coolant – replacement of Iron ore
Comparison with Iron ore
Iron Ore Mill Scale Briquettes
Fe (Total) 50 - 55 % 62 - 65 %
Silica Load 5 - 6 % 1.5 - 2.5%
Sulphur 0.03 - 0.15 % 0.05 - 0.1%
Sulphur Form In-Organic Organic
Moisture 3 - 5 % < 2%
Fines 20 - 40 % 5 - 10 %
Intangible Benefits Flame Shoot-up X
Difficult to handle in
Rainy SeasonX
Source of Hydrogen X
Red Fumes X
ID Fan Perfomance Improved
Bunker Jammng X
Summary
• JSW steel is front runner in adopting innovative and novel technologies for its
operation with wide range of raw materials.
• Continuous Innovations being carried out for sustainable growth.
• Innovation cell is created to monitor status and encourage employee.
• Innovation online portal created for logging the innovations