ITB Bandung, 24-27 September 2013 Teknik Metalurgi Dr.-Ing. Zulfiadi Zulhan Department of Metallurgical Engineering Institut Teknologi Bandung INDONESIA Seminar Nasional Besi dan Baja III 3rd Indonesian Iron and Steel Conference ITB Bandung, 24-27 September 2013 New Concept of Hot Metal Production using Rotary Kiln – Smelting Reduction Technology

Iron and Steelmaking Route

1 4 3 2 Blast furnace as first option for new ironmaking plant !!! Statistical Data in 2010 www.worldsteel.org 984.08 mio tons (70.3%) 4.51 mio tons (0.3%) 62.95 mio tons (4.5%) 347.77 mio tons (24.9%) 1 4 3 2 Blast furnace as first option for new ironmaking plant !!!

Development of Iron and Steelmaking Technology

Blast furnace (High Eficiency!!! High Productivity!!!) 6-8 hours, burden from top to tuyere level H2O = {H2O} 200°C Fe2O3 Fe2O3 3<Fe2O3> + {CO} = 2<Fe3O4> + {CO2} C C C C H2O C 2{CO} = {CO2} + <C> <MgCO3 > = <MgO> + {CO2} 3<Fe3O4> + {CO} = 3<FeO> + {CO2} Fe3O4 Fe3O4 CO2 <FeCO3 >= <FeO> + {CO2} 800°C CO2 CaO CO2 <CaCO3 >= <CaO> + {CO2} FeO FeO 3<Fe3O4> + 4{CO} = 3<Fe> + 4{CO2} CO CO CO CO <FeO> + {CO} = <Fe> + {CO2} FeO FeO + {CO} = Fe + {CO2} > 1000°C Fe Fe {CO2} + <C> = 2{CO} Fe Fe Fe Al2O3 CaO P2O5 Fe SiO2 + 2<C> = [Si] + 2{CO} CaS MnO SiO2 {CO2} + <C> = 2{CO} CO CO MnO + <C> = [Mn] + {CO} CO CO C Fe Si CO CO {O2} + <C> = {CO2} Fe Mn <C> = [C] 1800-2000°C N2 O2 S P O2 N2 CaO+SiO2+Al2O3 1500°C Residence time of gas: 1-10 seconds or more [S] + (CaO) + C = (CaS) {CO} 1400°C

Added Value Mining Regulation (UU No. 4 2009) and Source of Iron Export ban of raw material will be inforce in 2014 The limitation of blast furnace technology: Requirement of coke for reductant as well as for energy sources. Sourrce of Iron ore: Hematite/magnetite Iron sand laterite Reserves Pardiarto, B. 2011. Peluang Bijih Besi dalam Pemenuhan Kebutuhan Komoditas Mineral Strategis Nasional. Buletin Sumber Daya Geologi, Volume 6 Nomor 2.

Direct reduction technology

Direct reduction Technology 2001 -2010: share of sponge iron produced by rotary kiln process in the world increases steadily especially in India Reasons: - Easy to operation and to control Flexibility in term of raw material Proven technology www.midrex.com

Temperature sponge iron > 1000oC Metallization > 90% Rotary Kiln Temperature sponge iron > 1000oC Metallization > 90% Cooling of sponge iron, T < 100oC why sponge iron from rotary kiln shall be cooled down? Could hot sponge iron from rotary kiln be charged directly into smelting furnace? S: A. Chatterjee, Sponge Iron Production by Direct Reduction of Iron Oxide

Replace by Smelting Furnace Idea Replace by Smelting Furnace COREX (Smelter gassifier)? HiSmelt? ... Shaft furnace, HOTLINK and HyTEMP were applied in industry S: A. Chatterjee, Sponge Iron Production by Direct Reduction of Iron Oxide

COREX and Finex Gudenau: Eisen und Stahlerzeugung, Vorlesung, 2012 MSTS, Ironmaking volume, 1999

Idea Biswas, A.K., 1980, Principles of Blast Furnace Ironmaking, Cootha Publ.

Idea

Rotary kiln – melting furnace US Patent (1950) Rotary kiln – melting furnace it is not well documented and reported whether this process was applied in industrial scale US Patent: Harman and Loftus (US Patent 2,526,658) in1950 (process for smelting iron ore). Detail of melting furnace

New Concept (Patent Pending, Z. Zulhan, ITB) Smelting furnace Lower part of blast furnace Stove PCI Layout rotary kiln – smelting furnace

New Concept (Patent Pending, Z. Zulhan, ITB), e.g for laterite ore Off-gas Rotary Dryer Dust Screen Coal/coke breeze Mixer fluxes Off-gas Sintering Gas Gas cleaning Dust + Off gas Dust Coal Off gas Fluxes Stove Hot Air Rotary Kiln – Smelting Reduction Furnace (DSR-Z) Slag (granulated) Air Pulverized coal Pig iron (hot metal) / ferronickel

Advantages: The advatages of this technology for the current situation in Indonesia where coking coal is limited and electricity is not well equipped especially in the east part of Indonesia are following: 1. energy contained in hot sponge iron from rotary kiln can be beneficiated directly by charging hot sponge iron into smelting furnace to produce hot metal and then convert it into steel by intalling a converter (BOF). 2. No EAF is needed for melting of sponge iron which means that electricity is used only to operate the equipments (motors, valves, sensors, etc.), not for smelting. 3. Coal can be used as source of reductant as well as energy sources instead of coke. 4. Coal is used as primary energy for smelting. In case of electric arc furnace for smelting of sponge iron, coal is converted first into electricity which has efficiency of around 30%. The melting itself in EAF has energy efficiency around 50 – 70% which yields low overall energy efficiency.

Outlook The ouput of models: coal, flux, ore consumption, hotmetal composition Productivity dimension of rotary kiln, uptake and smelting furnace comparation of overall consumption for following route: - conventional route: rotary kiln – EAF -new concept: rotary kiln – smelting furnace - BOF

Thank You for Your Attention Email: zulfiadi@mining.itb.ac.id zulfiadi.zulhan@gmail.com