GASIFICATION AND THEGASIFICATION AND THEMIDREX® DR PROCESSMIDREX® DR PROCESS
By: Rob By: Rob CheeleyCheeley
Midrex Direct Reduction CorporationMidrex Direct Reduction Corporation
Presented at the:Presented at the:
1999 1999 Gasification Gasification Technologies ConferenceTechnologies Conference
MIDREXMIDREX
•• Technology CompanyTechnology Company
•• 80 employees80 employees
•• Located in CharlotteLocated in Charlotte
DIRECT REDUCED IRONDIRECT REDUCED IRON
•• Known as DRIKnown as DRI
•• Elemental iron produced as solidElemental iron produced as solid
•• Feedstock for steel mini-millsFeedstock for steel mini-mills
THE MIDREX PROCESSTHE MIDREX PROCESS
•• Converts iron ore to direct reduced ironConverts iron ore to direct reduced iron( DRI )( DRI )
•• 67% of World DRI Production of 3767% of World DRI Production of 37million tonsmillion tons
•• 47 Plants in 16 countries47 Plants in 16 countries
IRON ORE REDUCTIONIRON ORE REDUCTION
3 CO + Fe3 CO + Fe22OO33 --> 2 Fe + 3 CO --> 2 Fe + 3 CO22
3 H3 H22 + Fe + Fe22OO33 --> 2 Fe + 3 H --> 2 Fe + 3 H22OO
IMEXSA MIDREX PLANTIMEXSA MIDREX PLANT
SYN GAS CHARACTERISTICSSYN GAS CHARACTERISTICS
Temperature Ambient - 2700 F
Pressure < 300 psig
H2/CO Ratio All are acceptable
Gas Quality > 2 ; > 10 preferred
Methane 0 - 5 %
Sulfur < 0.3 %
Quality = ( % H2 + % CO ) / ( % H2O + % CO2 )
SYN GAS FLOW RATESSYN GAS FLOW RATES
FlowrateFlowrate Per t of DRIPer t of DRI
NmNm33 650 - 750650 - 750
SCFSCF 24,000 - 28,00024,000 - 28,000
MMBtuMMBtu 7.5 - 8.77.5 - 8.7
Assumes: Quality > 10 & 310 Btu/ftAssumes: Quality > 10 & 310 Btu/ft33
ECONOMICS IN U.S.ECONOMICS IN U.S.
Direct CostsDirect Costs
Iron Ore Iron Ore $ 58 / t$ 58 / t
CoalCoal $ 17 / t$ 17 / t
OthersOthers $ 18 / t$ 18 / t
Indirect CostsIndirect Costs
Capital ChargeCapital Charge $ 32 / t$ 32 / t
OthersOthers $ 5 / t$ 5 / t
TotalTotal $ 130 / t$ 130 / t
BEST LOCATIONSBEST LOCATIONS
•• East Asia East Asia
•• West Europe West Europe
•• Australia Australia
•• Brazil Brazil
•• India India
•• South Africa South Africa
KEYS TO VIABILITYKEYS TO VIABILITY
•• Use Excess Synthesis GasUse Excess Synthesis Gas
•• Use Refinery By-ProductsUse Refinery By-Products
•• Minimize Capital CostsMinimize Capital Costs
•• Integrated Mini-Mill ComplexIntegrated Mini-Mill Complex
INTEGRATED MINI-MILLINTEGRATED MINI-MILL
•• Gasification Gasification PlantPlant
•• MIDREX PlantMIDREX Plant
•• Steel MillSteel Mill
•• Power PlantPower Plant
INTEGRATED MINI-MILL FLOWSHEETINTEGRATED MINI-MILL FLOWSHEET
INTEGRATEDINTEGRATED MINI-MILLMINI-MILL
•• 2,700,000 t/y MIDREX Plant2,700,000 t/y MIDREX Plant
•• 2,400,000 t/y Steel Mill2,400,000 t/y Steel Mill
•• 360 MW Power Plant360 MW Power Plant
•• 16,000,000 SCF/h Synthesis Gas16,000,000 SCF/h Synthesis Gas
SALDANHA STEELSALDANHA STEEL
•• Near Cape Town, South AfricaNear Cape Town, South Africa
•• First First Gasifier Gasifier / DRI Combination/ DRI Combination
•• Uses COREX® ProcessUses COREX® Process
•• Started-up in 1999Started-up in 1999
COREX® Export GasCOREX® Export Gas
ItemItem Typical DesignTypical Design
HH22/CO/CO 0.50.5
Gas CompositionGas Composition
COCO 35 - 45 %35 - 45 %
HH22 15 - 20 %15 - 20 %
COCO22 35 %35 %
NN22, H, H22OO 1 - 6 %1 - 6 %
CHCH44 1 %1 %
TemperatureTemperature 100 - 140 F100 - 140 F
PressurePressure 2 - 25 2 - 25 psigpsig
SALDANHA STEEL PLANTSALDANHA STEEL PLANT
CONCLUSIONSCONCLUSIONS
•• GasifierGasifier / MIDREX is a viable option / MIDREX is a viable option
•• Integrated Mini-Mill has best economicsIntegrated Mini-Mill has best economics
•• Asia has best potentialAsia has best potential