COREX®
EFFICIENT AND ENVIRONMENTALLYFRIENDLY SMELTING REDUCTION

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ECONOMICALLY AND ECOLOGICALLY HOTMETAL PRODUCTIONADVANTAGES OF COREX• Product quality – hot metal
quality suitable for all steel
applications• Economic benefit – lowinvestment and operationalcosts due to the elimination of
coking and sinter plants• Ecologic benefit – lowest
process-related emission rates

YOUR CHALLENGEOUR SOLUTION

The conventional blast furnace routeis too costly and energy-intensive
to keep pace with dynamic market
changes, where even short- andmedium-term fluctuations show theirdramatic impact on iron production.
The need to use coke and sinter makes
it much more difficult to fulfill everstricter environmental regulations andachieve economical competitivenessbased on long-term sustainablegrowth. Rising energy demand,
continuous price increases for natural
gas and raw materials, and steadilydecreasing quality of iron ore dueto the global resource depletion are
formidable challenges today. Radical
changes are inevitable and are forcing
operators to revamp their production
routes and explore promising solutions
to continue developing their ironmaking business successfully andresponsibly.

Corex is besides FINEX® the only
reliable alternative to the conventional
blast furnace route. It frees fromthe need to invest in the erection,
operation and maintenance of
coking and sinter plants because
these additional facilities are notneeded at all. Because it combines
two decisive advantages, adaptableenergy management/production andoutstanding ecological compatibility,
Corex provides you with the key
technology for producing hot metal
in an economically and ecologicallysustainable manner. The ability to use
a wider spectrum of raw materials with
Corex will make you less dependent on
price trends for raw materials. As an
industrially and commercially provensolution, it already provides a numberof plant operators worldwide with all
the advantages to fulfill prospective
requirements for the iron and steel
industry. And how well prepared areyou?

• Resource preserving – use ofa wide variety of iron ores andespecially non-coking coals• Beneficial by-products –generation of a highly valuable
export gas for various purposes(electric power generation,
DRI production, or natural gas
substitution)

COKING PLANT
SINTER PLANT

COREX

BLAST FURNACEThe Corex process combines coking plant, sinter plant and blast furnace into a single iron making
unit.

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COREX
THE ALTERNATIVE TO THE CONVENTIONAL
BLAST FURNACE ROUTE
Conventional BF route
Fine ore

Corex route

Coking coalNon-coking coal

NOVEMBER 1989
Commissioning of the
C-1000 plant at ISCOR
Pretoria Works (South
Africa).

Lump ore/pellets

NOVEMBER 1995
Commissioningof the first Corex
C-2000 plant at
POSCO‘s PohangWorks (Korea).

Exportgas
Sinter plant

Reduction zone
Melting,
gasification zone

Top gas

Hot
blast

Hot
metal
and slag

HIGH FRACTION OF LUMP ORE

The main differences between Corex and a conventional
blast furnace route are:

The typical iron oxide mix for Corex is 30% lump ore and70% pellets. Operational results proved stable operations
with a lump ore fraction up to 80%. In addition, no sinter– and therefore no sinter plant – is necessary for optimal
operation.

• Up to 80% of the iron oxide fraction can be lump ore; nosintering is required

DIRECT USE OF NON-COKING COALAs the coal is chared inside the melter gasifier, evennon-coking coal can be used, making a coking plant
unnecessary. The high dome temperature exceeds
1,000°C, resulting in entire cracking of the coal‘s relievedhydrocarbons and avoiding the formation of tar.

APRIL 2000
Commissioning of
the Corex C-2000
plant No. 2 at JSW(India).

NOVEMBER 2007
The BAOSTEEL group started
up the first Corex C-3000
plant at its Luojing Works inShanghai (China).

MARCH 2014

Commissioning of a Corex
gas based MIDREXTM DR
plant at JSW (India)

MARCH 2011
The BAOSTEEL group started up thesecond Corex C-3000 plant at its
Luojing Works in Shanghai (China).
2011
Commissioning of the two Corex
C-2000 plants at ESSAR STEEL Ltd. in
Hazira (India)

Milestones of Corex

MAIN DIFFERENCES FROM THE BLAST FURNACE ROUTE• Non-coking coal can be used directly as a reducing agent
and energy source

DECEMBER 1998
Commissioning of theCorex C-2000 plantat ArcelorMittal South
Africa - SaldanhaWorks.

OxygenThe reduction process of Corex• Pure oxygen instead of nitrogen-rich hot blast

JUNE 1999
Commissioning of the MIDREXTM
DR plant based on Corex gas for
ArcelorMittal South Africa - SaldanhaWorks.
AUGUST 1999
Commissioning of Corex C-2000 plant
No. 1 at JSW (India).

Coking plant

Hot
metal
and slag

JANUARY 1999
Introduction of the Corex C-3000
module on the market.

USE OF PURE OXYGENWhile blast furnace operators aim to enrich the hot blast
with oxygen, Corex already uses high-purity oxygen,
resulting in nearly nitrogen-free top gas. Due to its highcalorific value, this gas can be recycled for reduction workor used for heat or energy generation. Depending on thesteelworks demand, additional value can be created withthe produced gas.

Corex ArcelorMittal South Africa, Saldanha Works – profitable and environmental friendly iron making

45A LOOK INSIDEEFFICIENCY AT WORK

Lump ore/pellets/
additives
Export gas

Coal,
coal briquettes

Ø 5.5m

Hot metal
and slagØ 7.8m

C-1000C-0.5M

C-2000C-0.8M

C-1.0M40 - 60 t/h

80 - 100 t/h
600,000 800,000 t/a

OxygenPCIThe Corex processØ 7.3mØ 9.4mØ 9.6mØ 11.5m

C-1.3M

C-3000C-1.5M
C-1.5M

C-2.0M

100 - 125 t/h

125 - 160 t/h

160 - 180 t/h

210 - 240 t/h

800,000 1,000,000 t/a

1,000,000 1,300,000 t/a

1,300,000 1,500,000 t/a

1,700,000 2,000,000 t/a

Available Corex modules

PROCESS DESCRIPTIONECOLOGICAL AND PROFITABLE

RECYCLING SAVES RESOURCES

EXTENDED RAW MATERIAL SPECTRUM

With Corex, all metallurgical work is carried out in two
separate process reactors – the reduction shaft and themelter gasifier. Iron ore (lump ore, pellets, or a mixture
thereof) is charged into the reduction shaft, where it isreduced to direct reduced iron (DRI) by the reduction gas
in counterflow. Discharge screws convey the DRI into themelter gasifier, where final reduction and melting takeplace in addition to all other metallurgical reactions. Hot
metal and slag are tapped as in conventional blast furnace
practice.

The reduction gas exiting the melter gasifier mainly
consists of CO and H2 laden with fine coal, ash, and irondust. This dust is largely removed from the gas stream
in a hot gas cyclone and is then recycled to the process.
Oxygen is injected into the melter gasifier when the coal
is combusted, resulting in the generation of a highly
efficient reduction gas. The top gas is subsequently cooled
and cleaned in a scrubber, after which it is available asa highly valuable export gas with a net calorific value ofapproximately 8000 kJ/m³ (STP) suitable for a wide range
of applications (e.g., power generation, DRI production,
natural gas substitution, and heating within the steel
works).

Due to an increased gas utilization which is based ongas recycling, gas production in the melter gasifier canbe significantly lowered, which is directly reflected inlower fuel and oxygen consumption. Slag production issubsequently reduced by more than 20%.

In terms of raw materials, the main advantage of Corextechnology compared to the blast furnace route is the
direct use of non-coking coal as the fuel/reducing agent
and lump ore as the iron oxide feed. While the use offine coal via pulverized coal injection is available for bothtechnologies, coal briquetting is applicable to the Corex
only. By coal briquetting it is possible to mix low-quality,
low-cost coal fines with coals of higher grades. This resultsin lower coal cost and a substantially wider spectrum ofcoals to be utilized in Corex. This important economic
advantage will counter limited raw material availability andprospective price increases in the future.

DIRECT AND EFFICIENT
From the coal route perspective, coal is directly charged
into the melter gasifier. It is gasified by injecting oxygen
into the melter gasifier, resulting in the generation of ahighly efficient reduction gas. This gas exits the melter
gasifier and is cleaned, cooled, and then blown into
the reduction shaft, reducing the iron ore to DRI in
countercurrent flow as described above.
Due to the high temperatures prevailing in the dome of
the melter gasifier (in excess of 1,000 °C), the higherhydrocarbons released from the coal during devolatilization
are immediately dissociated to carbon monoxide andhydrogen. Undesirable by-products such as tars andphenols are destroyed and therefore cannot be released tothe atmosphere.

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INCREASED GAS UTILIZATION
A recycling system consisting of a compressor station andCO2 removal makes it possible to utilize more export gas
for metallurgical work. This raises gas utilization to a higher
level and makes the overall process even more economicand environmentally friendly.

TYPICAL CONSUMPTION FIGURESStandard Recycle
optionFueldry940

770[kg/tHM]

Additives

265

185

[kg/tHM]

Oxygen520

455[m³/tHM]TYPICAL CONSUMPTION FIGURESStandard Recycle
option
Slag

340

265

[kg/tHM]

Export gas

1,650
8,000

1,410
7,500

[m3/tHM][kJ/m3]CUSTOMIZED PLANT OPERATION
The implemented recycling circuit allows the operator
to adjust the system according to on-site requirements– to minimize coal consumption or to maximize exportgas generation – in order to respond to the steelworks
demand. The reduced volume of export gas lowers theinvestment required for Corex export gas application, e.g.,a downstream power plant.

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A LOOK INSIDEEFFICIENCY AT WORK

Alternative

Corex export gas
451 MWthElectrical energy for export:

Conventional power plant

134 MWel
1,070,000 MWh/a

Combined cycle power plant(CCPP)

178 MWel
1,424,000 MWh/a

1 x Corex plantC-1.0M

HeaterElectrical energy
10 MWelCoal
973 MWth

Oxygen66,000 m3(STP)/hCorex

Corex export gas

Oxygen plant

Hot metal
1,000,000 t/a
125 t/hProduction of electricity (Basis: e.g. Corex C-1.0M Plant)

Depending on the composition of coal and the decision
whether gas recycling is applied or not, the amount andthe composition of the export gas can vary within definite
limits. The specific gas properties of the Corex export
gas are compatible with natural gas, allowing for a wide
variety of in-plant uses, including power generation by
combined-cycle technology and DRI production. For thechemical industry, this gas can also serve as a feed stockfor numerous applications.
PRODUCTION OF ELECTRICAL ENERGY
Regardless of the recycling decision and plant setup,with its excellent calorific value the Corex export gas is
excellent suited for power generation. When used in a
combined-cycle power station, the export gas is converted
to electrical energy with efficiencies up to 48%. Dependingon particular site conditions, a tailor-made production
route including power generation fulfills all requirementsfor optimized energy management. Beyond that, operators
benefit from value created by surplus electricity, which canbe used to supply public demand.

DRI
860,000 t/a
108 t/hProduction of DRI (Basis: Corex C-1.0 M Plant)

TYPICAL THERMAL ENERGY BALANCE(FOR 1 MTPA HOT METAL)PRODUCTION OF DRI

Plant setup

Standard

RecycleoptionEnergy input

973

790

[MWth]

Energyconsumption

522

450

[MWth]

Energy output

451

340

[MWth]TYPICAL ELECTRICAL ENERGY BALANCE* (FOR 1
MTPA HOT METAL)
Standard

RecycleoptionPower generation 216

155[MWel]

Internal power
consumption andoxygen plant

38

45[MWel]

Power export

178

110

[MWel]* Conversion ratio thermal energy:electricity 1:0.48

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DR export gas
33,000 m3 (STP)/hCO2
removal

28 MWelHot metal
1,000,000 t/a
125 t/h

ADJUSTABLE EXPORT GAS GENERATION

1 x Corex gas based
MIDREXTM DR plant

Another way to benefit from the surplus reduction potential
is to reheat and utilize the export gas in a downstream
direct reduction plant. According to the desired productmix, even more additional DRI can be produced comparedto hot metal, thus raising the gas yield for iron making to a
new level never imagined before.
LOWEST SPECIFIC CONSUMPTION RATES
A decrease of 25% in the fuel rate and an increase of up
to 20% in gas utilization compared to best-performing
modern blast furnaces are decisive driving factors,
especially when present and future mandatory CO2
reductions for the iron and steel industry are taken into
account. Even the calorific value of the direct reduction
export gas is higher than blast furnace top gas and, similar
to the Corex export gas, it can be utilized efficiently forvarious purposes.
COREX/DR COMBINATION DRIVING FACTORSDRI production

850[kg/tHM]

Fueldry

530[kg/tIron]

CO2 emissions< 1250[kg/tIron]

9PROFITABLE AND ENVIRONMENTALLY FRIENDLY
PREPARED FOR PRESENT AND FUTURE IRON
MAKING CHALLENGES
Corex
BFmin
BFmax

3,783
2,027
1,080

g/tHM

553
361
300
35
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Dust

SO2

NOX

Emission comparison - Blast furnace / Corex, (Source: BAT for the production of iron and steel – EU Joint Research Center)

Corex Baosteel, Shanghai Baosteel Pudong Iron & Steel Shanghai, China

WHAT IS ENVIRONMENTALLY FRIENDLY?

GREEN IS NOT ALWAYS EXPENSIVELOWER PRODUCTION COSTS

Corex and the blast furnace route are coal-based processes
reducing iron ore to sponge iron, which is subsequently
melted into hot metal. In both processes, the same productis generated out of almost the same raw material. A
question that arises – and not only from an economic pointof view – is “how do these production routes deal withunwanted impurities?”

Minimizing the emission values for the blast furnaceroute requires the highest investment for environmental
protection, disregarding all reasonable economic aspects.
This can already be seen in the case of blast furnace dust
emissions, where efficient but costly filter systems are
installed in the sinter and coking plant. The Corex values
are already far better than expected future standards.
Moreover, the full development potential of Corex has not
yet been realized with respect to a further reduction ofemissions.

Because coking and sinter plants are not needed with
Corex, production and investment cost are reduced
substantially. The extent of the savings depends, of course,on the local plant site and other specific conditions. Given
the recent dramatic increase in cost for metallurgical coaland energy, the Corex can typically save operators up to
10% in hot metal production costs in comparison to the
traditional blast furnace route.

A certain amount of environmentally harmful substances
are inevitable based on the raw material mix. Hence,
the objective of a sustainable iron making process is
to discharge these substances in an environmentallycompatible condition, or destroy them in the process itself.
Since the Corex Process captures most of the pollutants in
an inert state in the slag and the released hydrocarbons aredestroyed in the dome of the melter gasifier, no additional
investment or operational costs are incurred for a complex
gas or disproportional waste water conditioning plant.

GASEOUS EMISSIONS
Thanks to the in-situ coking of the coal in the melter
gasifier, a large portion of sulfur is captured in the slag,
dramatically decreasing emissions of gaseous SO2 or H2S.
Furthermore, pure oxygen is used instead of the hot air
blast, significantly reducing nitrogen emissions in the formof NOx and providing the advantages already mentioned
regarding dust emissions.

Essar Steel, India

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COREX SUCCESS STORIESSELECTED REFERENCES

COREX ESSARCOREX JSW

Customer: Essar Steel Ltd., Hazira, India

Customer: Jindal South West Steel Ltd. (JSW), Toranagallu, India

The challenge: Relocation of the two Corex plants from Asan Bay, Korea to Hazira, India and to successfully carry out a brownfield

The challenge: Economical iron making basis for a new steelworks in an isolated area with limited access to fuel gas.

implementation into the existing steel plant infrastructure.

Our solution: Corex-DR combination consisting of two Corex C-2000 plants with a total annual output of 1.6 million tons of hot metal and a

Our solution: 2 x Corex C-2000 plants with an annual production of 1.7 million tons of hot metal per year in blast furnace quality with highly

MIDREXTM DR plant with an annual output of 1.2 million tons of DRI

valuable export gas for substituting natural gas for DR production.

OUTLINECUSTOMER BENEFITOUTLINECUSTOMER BENEFIT

In 2007 Essar Steel decided to relocate the Corex plant
erected for HANBO STEEL, Korea to their existing steel
works at Hazira, India. Beside production of high quality
hot metal to be used in two new EAFs to improve the steel
quality, one main target was to substitute natural gas at
the existing MidrexTM DR plants. A special challenge was tointegrate the Corex plants into the existing steel works due
to very tight space availability.

• Lower investment and operation costs compared to theconventional blast furnace route

At Jindal South West Steel Ltd. (JSW), the two Corex
C-2000 plants formed the iron making basis for steel
production. As a special feature, plant wastes, such as
Corex, limestone/dolomite fines, and LD slag, are recycled
into the two Corex modules, either directly or indirectly
through the pellet/sinter plants. The synergy of Corex andblast furnace helped JSW steel to maximize the utilizationof solid waste and thereby reduced the cost of hot metal. In
addition, Corex export gas is used for the production of DRI
and as a backup in blast furnace stoves, boilers, and thesinter and pellet plant.

• Lower production costs compared to JSW‘sbenchmarking blast furnaces• Economical and environmentally friendly production of
hot metal• Reduced DRI production cost in the adjacent MidrexTM
plants due to substitution of high natural gas by Corex
export gas• Lower dependency on the local power and gas supply
ENVIRONMENTAL BENEFIT• Synergistic combination of Corex and blast furnaces• Stable operation and production of additional DRI in
separate Midrex® plant
ENVIRONMENTAL BENEFIT• Efficient recycling of metallurgical waste material• Production of valuable export gas for power generation• Considerably reduced SO2 and NOx emissions• Reduced phenol, sulfide and ammonium contamination ofwaste water• Resource preservation due to alternative raw material
consumption

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WE TAKE THE RESPONSIBILITY
ALWAYS AT YOUR SIDE

LIFECYCLE MANAGEMENTROUND THE CLOCK, ROUND THE GLOBE

Bayi SteelChina
1 x C-3000

BaosteelChina
1 x C-3000

Essar SteelIndia
2 x C-2000

Jindal South West
(JSW)
India
2 x C-2000 and
1 x DR plant

ArcelorMittal
South Africa
1 x C-2000 and
1 x DR plant

Corex plants in operation and under construction

THERE IS ALWAYS A GOOD REASON FOR COREXPRIMETALS TECHNOLOGIES LIFECYCLE SERVICES

Corex fulfills all additional requirements beyond an
economical and reliable iron making unit. Examples include
JSW in India, where two Corex plants were erected for asteelworks in an isolated area with no access to natural gas
or electricity; Baosteel in China, where a new steelworks
was erected in a water protection area with a demandfor electricity; and ArcelorMittal South Africa, where aCorex-DR combination forms the iron making basis fora steelworks in an environmentally restricted area with azero-emission restriction specified by law. The expansion
to a Corex-DR combination plant at JSW underlines theflexibility of Corex to respond to actual market demands inthe iron and steel business.

As a plant operator, you have conflicting needs. On the one
hand, your performance is measured each quarter against
short-term profitability expectations. On the other hand,
you have to think on a totally different timescale comparedwith the capital market. Depending on the lifetime of yourplant, you have to take 15 years or more into account. At
the very least, that’s 60 full quarters.

But thanks to our comprehensive expertise and integrated
approach to solutions, you benefit both in the shortand long term from our lifecycle services. In the short
term: Backed by our extensive experience with manyreference plants, we provide you with the certainty of fast,
dependable production start-up and shorter amortization
periods. In the long term: Our master plan guarantees
competitive performance for your plant in every phaseof its lifecycle. Whether we’re providing 24/7 technicalsupport, optimizing maintenance, or making permanent
plant improvements, we’re always working to ensure thecost-effective operation of your plant.

NEW INVESTMENT

IMPLEMENTATIONOPERATION

MODERNIZATION• On-site assessments• Start-up support• Migration packages• Consulting• Plant documentation• E&A spares andcomponents• Feasibility studies• Technologicalassistance• Financing
engineering• Training packages• Service contracts• Technical assistance• Individual training
packages• System upgrades• System add-ons• Expansion packages• Maintenance packages

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