1. Panias Dimitrios Associate Professor in Extractive Metallurgy National Technical University of Athens

2. 6/2/20142 Global Iron and Steel Production Global Copper Production Global Aluminum Production Million tonnes

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5. 5 Social EconomicEnvironment Bearable Equitable Sustain able Viable innovatIoninnovatIon i n n o v a t i o n

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7. 7 Red Mud 2kg Bauxite 5.1kg Al 2 O 3 1.93kg

8. 6/2/20148 Chemical Species %wt (dry basis) Fe 2 O 3 47.74% Al 2 O 3 16.22% CaO 10.73% SiO 2 6.09% TiO 2 5.93% Na 2 O 2.51% V2O5V2O5 0.21% -SO 3 0.60% -CO 2 1.63% H 2 O(cry)8.35% Resource for Pig-Iron Production Common Resources for Mineral Wool production

9. 6/2/20149 Total Utilization of Bauxite Residue Total Utilization of Bauxite Residue No Solid/Liquid Wastes No Solid/Liquid Wastes Red Mud Pig Iron Mineral Wool CO 2 off- gases

10. 6/2/201410 1MVA dust treating AC EAF with 1 ton Batch Capacity Melt Spinning Fiberizing Line 25 tons of BR has been treated

11. 6/2/201411 Pig Iron%w/w Fe (%wt) 93.44 C (%wt) 4.59 S (%wt) 0.07 P (%wt) 0.22 Si (%wt) 1.12 Cr (%wt) 0.50 Total 99.94 Used in Secondary Steel Industry as 21% w/w substitution of Steel scrap White Iron Grinding Balls

12. 6/2/201412 wool%w/w Fe 2 O 3 1.1 SiO 2 26.5 CaO 23.4 Al 2 O 3 31.1 Cr 2 O 3 0.1 MgO 8.3 TiO 2 6.1 Na 2 O 1.8 Wool of excellent quality λ = 0,034 W/m.K λ = 0,034 W/m.K Mean Fiber Diameter 7 μm Mean Fiber Diameter 7 μm Bright white color (low Mn content) Bright white color (low Mn content) High Mechanical resistance due to high TiO 2 High Mechanical resistance due to high TiO 2 Industrial pipes insulation

13. 6/2/201413 Extrapolation for a 5.0 MVA EAF treating 1300 tons of bauxite residues and producing 442 tons of pig iron and 931 tons of mineral wool per month Extrapolation for a 5.0 MVA EAF treating 1300 tons of bauxite residues and producing 442 tons of pig iron and 931 tons of mineral wool per month Pig Iron revenues (calculated at a market price of 415/t) amount to 25% of operational costs Pig Iron revenues (calculated at a market price of 415/t) amount to 25% of operational costs Mineral wool revenues depend on market price (depends on product quality and market demand) Mineral wool revenues depend on market price (depends on product quality and market demand)

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15. 6/2/201415 High Electrical Energy consumption (an upgraded energy form with high cost and exergy content) for production of chemical work and heat High Electrical Energy consumption (an upgraded energy form with high cost and exergy content) for production of chemical work and heat Molten Salts Electrolysis Al 2 O 3 = 2Al 3+ + 3O 2- Cathode: 4Al 3+ + 12e - = 4Al Anode: 6O 2- + 3C graphite = 3CO 2(g) + 12e - Increased Environmental Impact due to mainly CO 2 emissions Increased Environmental Impact due to mainly CO 2 emissions Low volumetric efficiency due to 2 Dimensional Electrolytic Reactor. That means, for a given production capacity, a big number of cells and therefore big industrial space are necessary Low volumetric efficiency due to 2 Dimensional Electrolytic Reactor. That means, for a given production capacity, a big number of cells and therefore big industrial space are necessary Typical Aluminum Smelter -around 300 electrolytic cells -125.000 ton/y Al production New generation smelters 400-500 kton/y Al production Located in Middle East, China, Russia, India, Malaysia and Africa

16. 6/2/201416 Al 2 O 3 + 3C = 2Al + 3CO (g) Substitution of a part of Electrical Energy with the chemical and thermal energy of carbon Substitution of a part of Electrical Energy with the chemical and thermal energy of carbon Decrease of waste heat Decrease of waste heat Higher volumetric efficiency due to 3 Dimensional Reactor Higher volumetric efficiency due to 3 Dimensional Reactor Potential for waste heat recovery Potential for waste heat recovery For a given production capacity - smaller reactor size and thus industrial space - less capital cost For a given production capacity - smaller reactor size and thus industrial space - less capital cost Electrolytic Process 7.42kg CO 2 1kg Al 1.93kg Al 2 O 3 15.3MJ C anode 56.24MJ Electricity 44.73MJ Electricity 20% decrease Carbothermic Process 24.23MJ C Reductant Cathode: 4Al 3+ + 12e - = 4Al Anode: 6O 2- + 3C graphite = 3CO 2(g) + 12e - 1.66kg CO 2.6kg CO 2 Recovery of 15.82MJ Reduction in indirect CO 2 emissions Decrease of CO 2 emissions Decrease of CO 2 emissions

17. 6/2/201417 2Al 2 O 3 + SiO 2 + 8C = 4AlSi 0.25(l) + 8CO (g) 1. Co-Reduction of Alumina and Silica Under high temperatures (>2500 o C) Under high temperatures (>2500 o C) Under vacuum (1500 o C) Under vacuum (1500 o C) Al 2 O 3 + 3C = 2Al (g) + 3CO (g) 2. Gaseous aluminum production all are proven in Laboratory Scale is now tested in Pilot Scale

18. 6/2/201418 2Al 2 O 3 + SiO 2 + 8C = 4AlSi 0.25(l) + 8CO (g) Carbon Source: Wood charcoal Binder: 7% corn starch 2600 o C <1000 o C Molded Al-Si Alloy Identification Number Al wt.-% Si wt.-% Ex. 1: Si/Al=0.26 (T=1300°C) 72.5325.58 Ex. 1: Si/Al 0.26 (T=700°C) 71.3725.95 33% of 42 Mt of Global Al- Castings are AlSi Castings 33% of 42 Mt of Global Al- Castings are AlSi Castings Al 77.07 wt.-% Si 22.93 wt.-%

19. 6/2/201419 Concept: Hollow electrode EAF Feeding Alumina-Carbon pellets directly in the arc zone Controlled feeding rate No liquid phase formation Water cooled lid acts as condenser Argon Overpressure No Liquid PhaseHomogeneous Condensed Material with Metallic Shine Almost Pure Aluminum

20. 6/2/201420 Concept: Reactor under vacuum Concentrated Solar Radiation provides process heat Condenser before vacuum pumps collects the metal. Energy of the process = pumping work (electricity) + concentrated solar radiation. Quartz Window ZIrconia Before test After test Condensed Deposit

21. 6/2/201421 Estimated gains of the new Alumina Smelter in Comparison to the Hall-Heroult Energy SourceEnergy SavingsReduction in GHG Emissions Exergy Efficiency Increase Coal based electricity16%35%3% Hydroelectricity10%65%5% Hydroelectricity for H-H and Concentrated Solar for New Smelter 68%65%82%

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