bio-carbon for blast furnace ironmaking - cancarb.ca bio-carbon working meeting_june 2012.pdfrole of...
TRANSCRIPT
Blast Furnace Ironmaking
• Reduction of iron ore to metallic iron
• Melting of metallic iron (Hot Metal)
CO
C + O2 Hot Metal
Fe + CO2 Iron Ore
heat
Atm
Coke
Role of Coke in Blast Furnace
Source of Reducing Gas
Source of Heat
Burden Support
Gas Distribution
Hot and cold strength of particular coke determines
its suitability for blast furnace ironmaking
Coke Properties
Cold Strength Tumbling Tests Stability
Hardness
Hot Strength Reacting with CO2 at high temperature followed by impact test
Coke reactivity index (CRI)
Coke strength after reaction (CSR)
Pilot Scale Bio-Coke Making Tests
Coke : Carbonization of coal blend
Bio-coke: Carbonization of coal blend partially substituted by charcoal
Hot Strength of Bio-Coke
Fine charcoal has a much stronger negative impact on CSR and
CRI than coarse charcoal
Bio-Carbon for cokemaking
Low in Ca: To maintain hot strength
Low in Na and K: To avoid alkaline accumulation
Low in P: To facilitate steelmaking
Auxiliary Fuel Injection
Coke
Auxiliary
Fuel
• To reduce coke
consumption on per tonne of
hot metal production basis
• Pulverized coal, Oil, Natural
Gas
• Substitute fossil carbon
injectant by bio-carbon
Fuel for Injection
• High combustibility: To ensure rapid gasification
• High in C and Low in O: To maximize coke
replacement and maintain furnace heat balance
• Low in Na and K: To avoid alkaline accumulation
• Low in P: To facilitate steelmaking