1. 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, September 2013
New Concept of Hot Metal Production using Rotary Kiln – Smelting Reduction Technology

2. Iron and Steelmaking Route

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

4. Development of Iron and Steelmaking Technology

5. 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] °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

6. 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 Peluang Bijih Besi dalam Pemenuhan Kebutuhan Komoditas Mineral Strategis Nasional. Buletin Sumber Daya Geologi, Volume 6 Nomor 2.

7. Direct reduction technology

8. Direct reduction Technology
: 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

9. 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

10. 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

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

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

13. Idea

14. 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

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

16. 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

17. 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.

18. 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

19. Thank You
for Your Attention