characteristics, Process, benefits, economics, and advantages

1. Dr. ANKITENDRAN MISHRA
Indian Institute of Technology, BHU, Varanasi

2. CONTENT
 INTRODUCTION
 IRON CARBIDES CHARACTERSTICS
 BENEFITS
 METALLURGICAL BENEFITS
 ENVIRONMENTAL BENEFITS
 PROCESS OVERVIEW
 COMMERCIAL PLANTS
 ECONOMICS
 ADVANTAGES of IRON CARBIDE
 CONCLUSION
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3. INTRODUCTION
 Premium quality feed for steel making- in EAF and
BOF’S
 It is clean and simple with excellent cost savings and
metallurgical advantages
 Only direct by-product is water
 Ancilliary by-product is CO2
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4. IRON-CARBIDE CHARACTERSTICS
 Density(iron carbide)=7640kg/cubic meter>Density(molten
iron)=6980kg/cubic meter. Intermetallic Compound
 Feed- not pelletized & products-not briquetted
 Iron carbide is completely free of sulphur and residual metals like- Zn
, Cu Sn , Cr etc.
Iron Carbide Chemical Analysis Compared to DRI and HBI
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5. BENEFITS
1. METALLURGICAL BENEFITS
 Preferred material for nitrogen control in EAF steel
making
 Being fine & heavy- can be easily injected into EAF’s
using submerged lances
 Being hard, dense , chemically stable& granular-easy to
handle and safe to ship
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6. BENEFITS…
2. ENVIRONMENTAL BENEFITS
 Lowest carbon emission of all virgin steel making
process(1.09kg CO2/kg of steel produced)
Carbon Emissions from Various Iron Ore to Steel Manufacturing Processes
 iron carbide produces much of its CO2 in a concentrated
stream- easy to sequester.
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7. PROCESS OVERVIEW
 The process converts iron ore—typically hematite (Fe2O3) or
magnetite (Fe3O4)—to iron carbide (Fe3C), using a strong reducing
gas composed of methane (CH4), hydrogen (H2), carbon monoxide
(CO), carbon dioxide (CO2), and water vapour (H2O).
 The process operates at a temperature between 565°C and 630°C
and at an absolute pressure of 4.5 atmospheres.
 Overall natural gas consumption is 14.8 GJ/mt of product.
 The nominal capacity of a single-module iron carbide plant is 1,000
mt/day & product quality is expected to be about 90% of the iron as
Fe3C. (ideally 85-95%)
 The iron carbide process does not remove impurities in the ore:
gangue components, such as silica (SiO2) and alumina (Al2O3),
pass through the process unchanged
 The cooled iron carbide product is exposed to dry magnetic
separation before being sent to product storage.
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8. Iron Carbide Process Flow Diagram 8

9. IMPORTANT COMPONENTS
 ORE STORAGE Hematite iron ore, which generally contains 63-65% iron, 1-
3% gangue, and 4-10% moisture, is the normal feed.
 ORE HEATER The ore heater raises the ore to 710°C , where it is held until
being fed to the fluidized-bed reactor.
 REACTOR FEEDING Two refractory-lined, lock hopper bins feed the heated
ore into the reactor.
 FLUIDIZED-BED REACTOR In the reactor, methane and hydrogen convert
the heated iron ore to iron carbide.
3Fe2O3 + 2CH4 + 5H2 ―› 2Fe3C + 9H2O
Natural gas reformed with steam, provides the necessary
hydrogen
CH4 + 2H2O ―› CO + 4H2
 PRODUCT HANDLING product discharges from the reactor via two lock
hoppers, releasing the product to ambient pressure & at approximately
587°C and cools to approximately 65°C on passing through a plate and
frame, water-cooled, product cooler.
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10. COMMERCIAL PLANT
NUCOR PLANT AT POINT LISAS, TRINIDAD, 1994
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11. COMMERCIAL PLANT…..
Qualitech Steel Plant at Corpus Christi, Texas,1999 11

12. ECONOMICS
 The battery limits capital for a 1 million annual ton capacity plant is $333 per
annual ton
 The operating cost depends upon the price of the basket of commodities
used for its manufacture.
OPERATING REQUIREMENTS
 In parts of the world, where natural gas is inexpensive, iron carbide can be
produced for approximately $80/mt plus the cost for iron ore.
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13. ADVANTAGES
 Most effective for producing low nitrogen and hydrogen steels
 Uses iron ore fines which is less expensive than iron ore
pellets
 Consists single stage converter and is therefore simple and
easy to control
 Closed loop process consisting 100% of the reagents input
 Never generates sticking material
 Operates at low temperature and is thermally efficient
 The only process byproducts are water and carbon dioxide(.)
 Much of the carbon dioxide exits the reformer in a
concentrated gas stream(.)
 Free from common residual metals like- Cu, Zn, Cr, Sn etc.
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14. CONCLUSION
 The iron carbide manufacturing process is simple
and robust.
 The process generates a product with outstanding
metallurgical properties and powerful economic and
environmental benefits.
 It makes high quality steels easier and at a lower
cost than by any other method.
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15. REFRENCES
 Dorel Anghelina, Geoffrey A. Brooks, and Gordon A.
Irons, “Nitrogen Control in EAF Steelmaking by DRI
Fines Injection,” American Iron & Steel Institute and
Department of Energy (AISE/DOE) Technology Roadmap
Program, 31 Mar 2004
 Gordon H. Geiger, “Iron Ore to Steel via the Iron Carbide
Route: an Analysis of the Environmental Impacts of the
Route,” paper presented at the International Symposium
on Global Environmental and Iron and Steel Industry,
Beijing, China, 1997
International Iron Carbide LLC
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