of Iron Oxide Concentrate University of Utah PI: H. Y. Sohn Postdoc: G. Han (1 st 1.5 yrs.) Lab Assts: M.E. Choi, Y.

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1 Suspension Hydrogen Reduction of Iron Oxide Concentrate University of Utah PI: H. Y. Sohn Postdoc: G. Han (1 st 1.5 yrs.) Lab Assts: M.E. Choi, Y. Zhang, Josh Ramos Partner Companies Dofasco Inc., Gallatin Steel, Ipsco, ArcelorMittal Steel, Nucor, Praxair, Timken, Ternium Mexico, and US Steel

2 Overall Objective Develop an ironmaking process based on: Hydrogen Direct use of concentrate Without coke Without pelletization/sintering Main goal: Significant reduction in energy consumption and CO 2 generation in the steel industry

3 Other Benefits Eliminate the cost and environmental problems in making and burning coke Eliminate pelletizing/sinter-making Produce iron with a low carbon content that can directly proceed to the refining process

4 Proposed Process Concept H 2 as reducing agent and fuel (portion or whole) Possible use of natural gas or coal Product - Solid or Liquid (Feed to steelmaking step or part of direct steelmaking process)

5 Major tasks vs. Progress Tasks Material and energy balances Progress Completed Impurity behavior evaluation Completed Determination of the kinetics of hydrogen reduction Critical data collection completed. Supplementary data collection continuing. Preparation for the pilot-scale test facility Completed Bench-scale test work Data collection in progress

6 Summary of Important Results Calculated energy savings up to 38% of BF process. Complete elimination or drastic reduction of CO 2 emission from ironmaking. Reduction rate determined to be sufficiently fast to apply a gas-solid suspension process to ironmaking. Possibility of eliminating the use of coke and pelletization/sintering, with associated generation of pollutants.

7 Analysis of Impurity Behavior Sulfur in iron produced by hydrogen reduction would remain at about the same % level as in BF. It could be lowered by reducing FeO content in slag. Phosphorus in iron could be lowered from the % level in BF down to 0.01 or lower depending on FeO content in slag.

8 Rate of H 2 Reduction Extrapolation of previous rate data: - Deemed too slow for suspension process Careful examination of data and other factors showed possibility of higher rate. - Basis for current project

9 Drop-tube Reactor System

10 Drop-tube Reactor System

11 Rate Determination Rate is fast enough for a suspension process in H 2 above 1200ºC.

12 Reduction at 1100 o C 2-second reduction (50% metallization) 10-second reduction (100% metallization)

13 Effect of SiO 2 100% reduction (1350 o C, 2.7 seconds)

14 Slide 13 B7 Mapping??? ByEobs, 8/23/2006

15 Bench-scale Test Facility

16 Bench-scale Test Work For higher reduction and feeding rate, longer residence time or higher T needed.

17 What s next This Phase Continue the pilot-scale test work. Collect more data at 1150 o C. Use a syngas to simulate a process with an internal burner. Evaluate methods to increase the reduction temperature above 1200 o C. Complete the determination of reduction kinetics with the drop-tube reactor experiment (with emphasis on the effect of water vapor).

18 What s next Beyond this Phase Phase 2 (Cost $2.5 MM): Comprehensive bench-scale tests - Univ of Utah facility Test of various gaseous reducing agents & fuels Flowsheet construction for industrial pilot facility Complete material and energy balances Design & cost estimation of the industrial pilot test facility Phase 3: Industrial pilot tests: 75, ,000 tpy (Cost ~$50 MM) 10 25,000 tpy (Cost ~$15MM)