Session II: DRI in focus. DRI in use: How can DRI (HBI) be utilized in the Blast Furnace and BOF? by Ralph Smailer, Director/Owner Metserv

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1 Session II: DRI in focus DRI in use: How can DRI (HBI) be utilized in the Blast Furnace and BOF? by Ralph Smailer, Director/Owner Metserv

2 Ironmaking and Steelmaking Practices with HBI Blast Furnace Practice with HBI

3 Discussion Topics BF material handling requirements HBI storage Compatibility with current practice Need to model entire BF process Run simulations to obtain sensitivity curves Display graphical results

4 Logistics for BF Raw Materials Large volumes required; 4Mtpy to 10 Mtpy Open transport and storage Rugged weather resistant products Iron ore pellets Steel scrap Limestone HBI Suitable for conveyor movement

5 How D0 You Want Delivery?

6 Ocean bulk carrier, 20,000 t

7 Ship Discharge dust control

8 Unloading of river barge

9 Build large stockpiles

10 Reclaim from open stockpile

11 Blast furnace overall view

12 BF Conclusions As with all steelmaking operations, the actual use of HBI in the BF is highly dependent on the relative costs of: 1. Iron ore pellets 2. Coke And offset by additional profit if increase in production at BF results in increased sales.

13 Advantages of HBI Use in Blast Furnace Use of HBI allows greater flexibility in BF production rates, allowing output to be increased during periods of increased hot metal demand. (v restarting an idled furnace) HBI is easier to use than scrap in the materials handling system of the blast furnace Rule of thumb is that for each 10 percent increase in burden metallization: Production rate increases 8%. Coke rate decreases 7%. Reduction of coke rate results in significantly reduced CO 2 emissions

14 BF cross section

15 BF Process Model Value of HBI in BF requires analysis of entire process A model simulates an actual BF operation and burden HBI increases production rate Cost of BF iron calculated for each simulation HBI reduces coke rate HBI reduces CO 2 emissions

16 HBI v Coke Rate 600 Coke rate kg/mthm HBI kg/mthm 250

17 HBI v Production MTHM/day HBI kg/mthm

18 HBI v Top Gas CO TG CO 2 kg/mthm HBI kg/mthm

19 Ironmaking and Steelmaking Practices with HBI BOF (Oxygen Converter) Practice with HBI

20 1. Use as a Charge Pad Value: reduced refractory cost, and increase availability Action: Daily gunning time, campaign life Evaluate: Data from existing customers 9. Transport Properties Value: Feeds easier in existing systems Action: Availability and timing of feed system Evaluate: Plant data 2. Predictable Quality Value: will give consistent operations Action: fewer off spec, heats, improved tap to tap time Evaluate: plant data 3. Physical Properties Value: High HBI density increases charge density Action: Reduces time involved in charging scoops and trimming Evaluate: End tap to change time Value of HBI to the BOF Plant 8. Adjust Heat Weight Value: Can optimize tap weight Action: Increase average tap weight Evaluate: Plant data 7. Minimize Storage Cost Value: Less storage space Action: High bulk density Evaluate: Table of charge material bulk densities 6. Technical Support Value: Local issues dominate results Action: Audit of plant operations Evaluate: Plant information and data 4. Charge Coolant Value: Reliability of feedstock Action: Long term contract Evaluate: BOF computer 5. End Blow Coolant Value: Accurate and point temp Action: Percent hit rate Evaluate: Plant data

21 Charging Practices

22 HBI Use as a Coolant Coolant Practical Cooling Effect Relative to Scrap Scrap 1.0 Iron Ore Limestone HBI 1.2

23 Phosphorus Reports to Slag Phase Fe, O intensity Distance (um) O Fe P P intensity

24 Effect of Basicity on Phos in Tap

25 Progress of Melting Normal C Briquette 5 sec 15 sec

26 Conclusions Use of HBI in the BOF is well practiced and understood Different value proposition to EAF Melting in high carbon baths is key to operation control Phosphorus in HBI has little effect in BOF (similar to an EAF)

27 Acknowledgement The use of materials previously produced for the Hot Briquetted Iron Association (HBIA), now the International Iron Metallics Association (IIMA) are gratefully appreciated. By Ralph Smailer, Director/Owner, Metserv