steelmaking by molten oxide...
TRANSCRIPT
![Page 1: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/1.jpg)
Steelmaking
by
Molten Oxide Electrolysis
Department of Materials Science
& Engineering
Massachusetts Institute of Technology
Cambridge, Massachusetts
Donald R. Sadoway
![Page 2: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/2.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
goal of the research
develop a carbon-free technology for the production of iron by molten oxide electrolysis
![Page 3: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/3.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
(FeOx) Fe(l) + ½ O2iron
iron
green ironmaking: cell schematic
x
![Page 4: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/4.jpg)
world capacity: ~40 million tons/year
aluminum produced by electrolytic reduction of Al2O3
decompose Al2O3 dissolved in Na3AlF6 (T = 960°C)
liquid Al (-) and CO2 (+)
find an inert anode & molten oxide electrolyte
Charles Martin Hall, USAPaul L.T. Héroult, France
1886
![Page 5: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/5.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
Technology Needs: dateline 2050
![Page 6: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/6.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
Technology Taxonomy: Reducing Agents
![Page 7: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/7.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
Environmental Impact & Energy Savings
![Page 8: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/8.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
Environmental Impact & Energy Savings
what did the European study conclude?
CO2 emissions reduced from 1750 kg/tonne liquid steel
for benchmark blast furnace technology
to 345 kg/tonne liquid steel: a five-fold reduction
90 g CO2/kWh for generation of electric power
equivalent energy consumption: MOE vs benchmark
![Page 9: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/9.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
Environmental Impacts & Other Benefits
zero GHG emissions when electricity is carbon-free
byproduct tonnage oxygen
no coke ovens, blast furnace, BOF
treatment of hazardous waste,
e.g., chromate sludge
![Page 10: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/10.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
Technical Challenges & Barriers
suitable electrolyte: no electronic conductivityinert anodeoperational stability of cell
service life of cell components
metal purity
![Page 11: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/11.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
progress to date:
designed, constructed, and operated laboratory-scale cell up to 1750ºC
conducted electrochemical testing on candidate electrolyte melts
demonstrated production of liquid iron and oxygen gas by electrolysis in laboratory-scale cell
![Page 12: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/12.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
electrolytic production of molten iron:
cathode: Mo
anode: Pt
electrolyte:
CaO - MgO - SiO2
feed: FeOcrucible: Moreactor tube: Al2O3
![Page 13: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/13.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
constant-current electrolysis at 1575oC
current density: ~1 A cm-2
iron
electrolyte
Mo crucible
![Page 14: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/14.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
more electrolytic production of molten iron:
iron
![Page 15: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/15.jpg)
SEM and EDX analysis
![Page 16: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/16.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
what have we learned?
deposition of iron is feasible in these
meltsvery high current densities are sustainable
5 A cm-2 observed; maybe higher!
c.f. 0.7 A cm-2 in Hall-Héroult cell15⋅ productivity of aluminum smelting
4 capable of producing tonnage metal
![Page 17: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/17.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
what else have we learned?
first evidence of inert anode
full realization of the molten oxide electrolysis concept
carbon-free steelmaking with tonnage industrial oxygen as by-product
![Page 18: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/18.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
next steps: phase 2
design, build, & operate pre-pilot cell
- current: 4000 A = 100⋅ today’s lab cell
- externally heated
- operating temperature: 1675ºC
- daily productivity: 67 kg Fe & 29 kg O2
![Page 19: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/19.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
acknowledgments
Dr. Aislinn SirkMr. Andrew GmitterVisiting Professor Dihua Wang Dr. Chanaka DeAlwis
Thank you for your attention!
![Page 20: Steelmaking by Molten Oxide Electrolysisweb.mit.edu/course/3/3.a30/www/refs/sadoway_gm08.pdfSteelmaking by Molten Oxide Electrolysis Department of Materials Science & Engineering Massachusetts](https://reader030.vdocument.in/reader030/viewer/2022021616/5e66e232d28e992f705b44f2/html5/thumbnails/20.jpg)
AISI Annual Meeting, Phoenix, AZ May 6, 2008Sadoway
towards carbon-free steelmaking