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Update on North American Ironmaking. Joseph J. Poveromo Quebec Cartier Mining Company Fred C. Rorick Rorick, Inc
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Update on North American Ironmaking Joseph J. Poveromo Quebec Cartier Mining Company Fred C. Rorick Rorick, Inc ABM 2nd International Meeting on Ironmaking, 1st International Symposium on Iron Ore, September 12 – 15, 2004, Vitoria – Espirito Santo, BRAZIL
TOPICS Blast Furnace ironmaking Alternative Ironmaking Processes Future Prospects
Problems of North American Blast Furnace Sector • External – EAF mini-mill competition, imports, environmental mandates • Internal – limited capital for modernization, high legacy costs, poor profitability • Consequences – reduction in hot metal, coke & sintering capacity – excess pellet plant capacity
Response of North American Blast Furnace Steelmakers • Non-technical – consolidation, reduce legacy costs, currency changes, markets • Technical improveraw materials, upgrade existing facilitiesto: increase productivity, reduce reductant rate and extend lining life
North American BF’s – Increased Productivity, Reduced Fuel Rates Key factors: fluxed pellets, improved acid pellets improved coke quality higher levels of natural gas, coal injection high levels of oxygen enrichment – lower cost oxygen-pipelines, on-site plants higher blast temperatures furnace upgrades: charging, cooling, casting
Extend Lining Life to 8 – 12 years + Enhanced cooling and refractory systems - intensive plate cooling, copper staves Remote repair methods - gunniting, grouting, shotcreting Hearth life extension - North American carbon, coke quality Burden distribution equipment PW or MA tops on 25 of 41 furnaces
Weighted (by Production Rate) Averages of Reductants by AISI BF’s (4) Hot Metal # of Reductant Usage, kg/tHM Production, Working Coke Coal Oil Gas Tar COG MT BF’s Lump Nut Total 1990 55 60 454 1 455 1 12 23 3 0 1995 61 51 402 8 410 34 13 38 1 1 2002 50 38 377 23 400 60 7 29 2 3
Increased Furnace Productivity Furnace Hearth Productivity Burden Injectant Dia., M T/M3/day AK Middletown BF 3 8.9 3.9 pellets,HBI gas Dofasco 4 BF 8.5 2.9 pellets oil Severstal NA C 8.8 3.1 pellets gas ISG. Sp.Pt. L BF 13.5 2.5 sinter/pellets coal
ISG Sparrows Point Ispat Inland L Furnace 7 Furnace Hearth diameter, m 13.5 13.7 Burden, kg/tHM Sinter 1040 228 Acid Pellets 534 0 Fluxed Pellets 0 1350 Lump ore, siliceous ore, etc 48 13 Reductant use, kg/tHM Large coke 316 319 Small coke 24 22 Coal 149 155 Natural gas 1 0 Top gas utilization, % 50.4 49.2 Slag volume, kg/tHM 270 265
Waste Oxide Processing • 7 Remaining sinter plants • Direct BF charging: BOF slag, pellet chips • Cold bonded briquettes, < 5% of burden • DR options, Severstal RHF plant • Landfill options
Coke Supply Challenges • US Coke Oven Capacity: 14 MTPY • Expensive Imported Coke • Maximize Injection of Coal, Gas, etc • Use HBI – ISG Circored Plant ?? • Rebuild Slot Oven Batteries • Heat Recovery Cokemaking - Indiana Harbor Coke Corp - ISG Haverhill Coke Battery, 0.8 MTPY
Development of Competitive Processes & Process Routes • Smelting reduction – Corex, HIsmelt • Direct reduction/scrap/EAF steelmaking route • Hot metal/scrap/EAF steelmaking route • Alternative (pig iron) iron/scrap/EAF steelmaking route
Development of Alternative Ironmaking Processes o large scale ironmaking - avoid cokemaking, sintering steps preceding blast furnace – most efforts have failed except for Corex – high capital cost? o small scale ironmaking - provide iron units to EAF mini-mill sector – only shaft furnace gas based plants ( Midrex, HyL ) so far successful in North America o process waste oxides at both EAF and BF-based steel plants – limited success
North American Direct Reduced Iron ( DRI ) Production • Main process route in Mexico > 5 MTPY shaft furnace ( HyL, Midrex ) DRI • USA, Canada: < 2 MTPY DRI ( Ispat Sidbec, ISG Georgetown ); other facilities down due to high gas prices: AIR, Corus Mobile • North America major importer of metallics: HBI (Venezuela ); pig iron ( Brazil, Russia )
North American Shaft Furnace DRI Developments • Application of pellet coating techniques; increase bustle gas temperature • Midrex – OXY+ system • HyL – self reforming, hot charging of DRI ( HyTemp system )
EVOLUTION OF MIDREX FURNACE PERFORMANCE – Ispat Sidbec DRI Reducing O2 Nat. Elec. Production Gas Temp.Addition Gas Cons. T/hr C Nm3/T Nm3/T kWh/T 1970’s 88.8780 0.0 268.6 135 1980’s lump ore100.3850 0.0 262.3 120 1990’s coat pellets110.2918 0.0 257.9 109 late90’s, O2 inj.121.51050 17.5 260.3 99 2000 OXY+ 129.2961 30.2 265.8 93
Coal-based Alternative Ironmaking • Iron Dynamics, Inc ( IDI ) – hot metal process to feed SDI’s EAF flat-rolled mini-mill, IDI is an RHF(rotary hearth furnace)/SAF (submerged arc furnace ) process – start with briquettes of iron ore/waste oxides/coal, produce DRI in RHF, then melt DRI in SAF – plant restarted late 2003 • Mesabi Nugget Demonstration Plant of Kobe ITmk3 pig iron nugget process
Coal-based Alternative Ironmaking • HIsmelt plant ( 0.8 MTPY pig iron ) in Kwinana, Australia – JV involving Nucor • Nucor/CVRD JV to build mini-blast furnaces in Brazil to produce pig iron for Nucor EAF’s in USA • RHF waste oxide plants – built at EAF and BF/BOF plants; all are currently idle
Role of Quebec Cartier Mining Company in North American Ironmaking • QCM mines iron ore in Quebec-Labrador Trough, with pellet plant, port facilities at Port Cartier on St. Lawrence Seaway. • Mt. Wright mining, concentrating: produce 13 MT; mining and upgrade 2.4 MT of raw ore at 32 % Fe to yield 1 MT of concentrate: specular hematite at 66 % Fe. • Produce pellets ( 8.7 MTPY ) in (2straight grate machines, 464 m2 ) for BF and DR use • Ship to Europe, N. America, Asia
Chemistry of QCM’s Mt. Wright concentrate and pellets Fe SiO2 Al2O3 CaO MgO Mt. Wright concentrate 66.0 4.90 0.33 0.07 0.05 TiO2 P S Mn 0.18 0.015 0.005 0.025 Blast Furnace pellets Fe SiO2 Al2O3 CaO MgO Fluxed 63.3 3.75 0.50 3.68 1.30 Low SiO2 Fluxed 65.1 2.50 0.40 2.25 1.50 Acid 65.1 5.20 0.45 0.60 0.25 DR grade pellets 67.8 1.65 0.35 0.50 0.30
US Steelmaking vs. Off-shore slabs Advantages of existing blast furnace plants: fully depreciated plants high labor productivity, < 1 man-hour/ton local coal, equity pellet plants Off-shore slab plants – added costs capital recovery ocean freight
AISI Actual – 2002 ICSTI’03 Forecast - 2015 Blast Furnace DR DS* Blast Furnace DR** DS M tonnes # of BF’s M tonnes # of BF’s USA 39.4 31 0.5 <0.1 33.0 25 1.0 2.0 Canada 8.0 5 0.2 0 8.0 5 1.0 1.0 Mexico 3.5 3 4.6 0 4.0 3 6.0 0 ------------------------------------------- ---------------------------------------- 50.9 39 5.3 <0.1 45.0 33 8.0 3.0 * IDI (RHF/SAF), HIsmelt, ITMk3 ** Midrex, HyL or RHF waste oxide
Conclusion - Key North American Developments • “Heat Recovery”Cokemaking • Blast Furnaces – high productivity, “endless campaigns”, high use of O2, pellets, HBI • Midrex, HyL DR – higher productivity, metallization: coated pellets, O2, hot discharge • Coal based alternative ironmaking – IDI, ITmk3 processes