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Ferromanganese research in Norway
� Introduction; Me, NTNU and SINTEF
� Manganese research at NTNU/SINTEF
1
FeMn-S.Bunkholt 2007 SiMn-S.Bunkholt 2007
Prof. Merete TangstadNorwegian University of Science and TechnologyDepartment of Material Science and Engineering
� Department of Material Science and Engineering, NTNU (since 2004)
� Eramet 2000-2004, R&D
� Elkem 1989-2000, R&D and Furnace Metallurgist
� PhD at NTNU in Cokebed Relations
2
� FeMn/SiMn furnace operation
� Fundamentals of the Si production
� Feedstock to solar cell Si production
Norwegian University of Science and Technology - NTNU
3
FACTSFACTS
NTNU key figures 2008
53 departments in 7 faculties
NTNU Library
Museum of Natural History and Archaeology
20 000 registered students
2 850 degrees awarded
4
2 850 degrees awarded
314 doctoral degrees awarded
4 500 person-years
2 700 employed in education and research; 557 professors
Budget: EUR 550 million
560 000 m2 owned and rented premises
Degrees awarded in 2008
Lower degrees Higher degrees
Technology [not offered] 1 098Social Sciences 252 333Humanities 229 176Science 104 123Architecture [not offered] 90
EDUCATION
5
Architecture [not offered] 90Medicine [not offered] 117Psychology [not offered] 55Fine Art 13 7Performing Music 20 6Teacher Training Diploma 212 [not offered]
TOTAL 830 2 029
6
Education for international students
� No tuition fees
� Must document a minimum of NOK 85 000 (EUR 10 000) per year to cover living expenses
Categories of international students at NTNU:
� Exchange students
EDUCATION
7
� Exchange students
� Degree-seeking students (undergraduate and graduate)
� International master's programme students
� Visiting/non-degree students
� NUFU students
� PhD candidates
International Master program from 2008Silicon and Ferroalloy production
Ex Subject no.
Subject title Note Autumn F Ø S
Spring F Ø S
Credits Exam
1h
1h
1h
1h
1v
TMT4155
TMT4280
TMT4325
TMT4305
TMT4150
HETEROGEN EQUILIBRIA
EXTRACTIVE METALLURGY
REFIN/RECYCL METALS
ELECTROMETALLURGY
REFRACTORIES
4 2 6
4 2 6
4 1 7
3 1 8
4 2 6
7,5
7,5
7,5
7,5
7,5
Autumn
Autumn
Autumn
Autumn
Spring
8
1v
1v
1v
1v
TMT4150
TMT4230
TMT4165
MT8301
REFRACTORIES
METALLURGICAL ENGINEERING
MAT/ELECTROCH, PR.WORK
CARBON MAT TECHN
4 2 6
4 2 6
2 6 4
2 2 8
7,5
7,5
7,5
7,5
Spring
Spring
Spring
Spring
Total weighing
60,0
2h
2h
2h
TMT5500
TMT5505
TMT4300
PROC MET/ELECTR SP
PROC MET/ELECTR SC
LIGHT AND ELECTRON
MICROSCOPY
24
12
4 2 6
15,0
7,5
7,5
Autumn
Autumn
Total weighing
30,0
2v Master Thesis 30,0 Spring
Department of Materials Science and Engineering - DMSE
• Metallurgy• Electrochemistry• Inorganic chemistry
• Staff of 125 persons• 21 professors (+10 adjunct professors)• ~110 1st – 5th grade students
9
• ~110 1st – 5th grade students• ~ 10 exchange students • 60 Ph.D. students• 20 post doc.
Norway’s leading institution for teaching and research on materials
Materials one of NTNU:s priority areas
Areas of research - DMSE
Light metals (Al, Mg)ElectrolysisMelting, casting, weldingFormingMicrostructure & PropertiesAlloy developmentRefiningRecycling
Ceramic materialsHigh strengthFunctionalNanostructures
Energy TechnologyFuel cellsHydrogen storage
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Recycling
Ferroalloys & siliconRaw materialsFerroalloy productionSilicon for solar cellsRefiningEnvironmental control
Hydrogen storage
OthersSteelCorrosionPowder metallurgyCatalysis….
11
SINTEF
SINTEF is one of Europe’s largest independent research organizations
Turnover NOK 1.7 billion, 1700 staff, 350 of these in Oslo
Established in 1950 as NTNU’s contract research organization
Contract research in technology, natural sciences,
R & D
12
Contract research in technology, natural sciences, medicine and social sciences
Cooperation with NTNU in terms of staff, equipment, laboratories and dissemination
13 Gemini Centres for joint NTNU/SINTEF R&D
Many NTNU staff are permanent SINTEF advisers
Many SINTEF staff are adjunct professors at NTNU
The SINTEF Group’s turnover in 2004,
by institute and research company
SINTEF Materials and Chemistry
SINTEF ICT
SINTEF Technology and Society
13
Gross operating income in NOK 1.7 billion
SINTEF Health Research
SINTEF Energy Research
SINTEF Fisheries and Aquaculture
SINTEF Petroleum Research
MARINTEK
SINTEF Holding
0 50 100 150 200 250 300 350 400 mill
The Norwegian Ferroalloy Producers Research
Association (FFF)
� Founded by the Norwegian ferroalloys industry to carry
out joint research on ferroalloy processes and products at
NTNU/SINTEF.
� Aims to maintain the Norwegian ferroalloys industry's
position at the forefront of developments in the production
14
position at the forefront of developments in the production
of ferroalloys and the supply of electro-metallurgical
technology and equipment.
� The aim is to pursue environmental improvement in the
ferroalloys industry.
� Support education of MSc’s and PhD’s for the ferroalloy
industry
The Norwegian Ferroalloy Producers Research
Association (FFF)
� Formed in 1989
� Members:Elkem ASAFESIL ASAFinnfjord Smelteverk AS
15
Finnfjord Smelteverk ASValeEramet Norway
� Annual Budget ~10 mill. NOK/year
� 4 – 6 PhD students on average
Mn-ores
Carbon materials
El-energy
16
Ferroalloys
1500-1600ºC
17
FFF - MANGANESE RESEARCH 1990-2010
� PROCESS MECHANISMS
�HC FeMn and SiMn Processes
�Pilot scale experiments
�Energy and mass balances
�Modeling of HC FeMn process
�Mineralogy of ores and agglomerates
� PREREDUCTION ZONE – Low temp. zone
�CO reactivity of manganese ores –kinetics and red. mechanisms
18
kinetics and red. mechanisms
�Thermal strength
�Thermal conductivity raw materials
�CO2 reactivity of carbon materials (incl. K)
�Use of agglomerates
�Fines generation of ore and carbon materials.
�Zn and K circulation in furnace
FFF - MANGANESE RESEARCH 1990-2010
� COKEBED ZONE – High temperature zone
�Melting relations
�Liquidus relations in HC FeMn and SiMn slags
�Wetting properties slag/carbon
�Slag kinetics
�C-reactivity
�Electrical resistivity of carbon
19
�Electrical resistivity of carbon materials
�Equilibrium data – experimental and databases
� Smelting reduction of HC FeMn
� Sludge recycling
� Biocarbon
� Emissions (incl. Diffuse emissions)
PhD Thesis - Manganese
� Ding W: Equilibrium relations in the production of manganese
alloys. 1993
� Skjervheim T A: Kinetics and mechanisms for transfer of
manganese and silicon from molten oxide to liquid manganese
metal. 1994
� Tangstad M: The high carbon ferromanganese process - Coke
bed relations. 1996
20
bed relations. 1996
� Wasbø S O: Ferromanganese furnace modelling using object-
oriented principles. 1996
� Berg K L: Gaseous reduction of manganese ores. 1998
� Hoel E G: Structures and phase relations in silicomanganese
alloys. 1998
PhD Thesis - Manganese
� J.Fenstad: Liquidus relations and thermochemistry within the
system Fe-Mn-C-O. 2000
� R.J.Ishak: Reaction kinetics for reduction of manganese ore
with carbon monoxide in presence of carbon. 2002
� J.Kozarowski: CO2 reactivity of carbon materials, 2006.
� J. Safarian: Slag-carbon reactivity, 2007.
21
� J. Safarian: Slag-carbon reactivity, 2007.
� P.A.Eidem: Electrical resistivity of carbon materials. 2008
� D.Slizovskiy: Sludge – from waste to product. 2011
� M.Ksiazek: Thermal conductivity of manganese ores. 2011
� T.Brynjulfsen: Agglomerates on furnace operation. 2013
Pilot experiments- Process mechanisms
150 mm
Silica sand
E
l
e
c
t
r
o
Charge
22
High Alumina
monolithic lining
Carbon paste lining
Tap hole
Bottom electrode
40 cm
50 cmo
d
e
Thin layer of
3mm size coke
Furnace in Operation
23
Charging Tapping
Dismantling the furnace
24
Shell and silversand removed Casting with Epoxy
Pilot experiments- Process mechanisms
25
Pilot experiments- reaction mechanisms
Tapped slag: 25%MnOTapped slag: 18.6%Al2O3 Tapped metal: 20.15%Si
26
1012
842
34128
31229
8
28
2726
302840
36364513
38253820
27,35
28
17
3022
13,1618,2221
17,2117,22217
18121415
15
016
27
Pilot scale experiments – Results
� Reaction mechanisms
� Geometry of zones
� Structure of cokebed
� Resistivity of cokebed
28
� Wettability of carbon materials
� Accumulation of SiO2 in high temperature zone
� Reduction behaviour Mn ore
� Reduction path – slag and metal composition
Al2O3+SiO2
60
70
80
90
1000
10
20
30
40
(A/S=0.5)
Basicity line = R
eduction path
Liquid area1500 oC
Basicity line = reduction path
29
MnO0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
Σbas
50
60
70
80
90
100Basicity line = R
eduction path
Basicity line = Reduction path
MnO reduction by solid carbon
(MnO) + C = Mn + COThis reaction has been studied in graphite crucibles
Some important points:� 1- MnO reduction takes place in
two stages, a fast stage following
by a much slower stage
� 2- The transition from first fast
stage to the second stage occurs
Effect of temperature on weight loss
-2
-1
0
weight loss [g]
30
stage to the second stage occurs
when slag reaches its liquidus
composition and MnO activity
starts to decrease
� 3- The rate of reaction increases
by increasing temperature, the
reported activation energies are
in good agreement (about 370
KJ/mol).
-7
-6
-5
-4
-3
-2
0 2 4 6 8 10
time [h]
1450oC
1500oC
1550oC
In situ furnace – melting behaviour
31
Melting behavior at increasing temperature
32
Biocarbon
1997 - 2001: ”The use of biocarbon in Norwegian Ferroalloy Industry”22.3 mill NOK (2.5 mill USD)
2002 - 2004: ”Environmental friendly reduction processes”
33
2002 - 2004: ”Environmental friendly reduction processes”8.5 mill NOK (0.95 mill USD)
Long term goal
� Reduce emissions of CO2 from fossil carbon sources in Norwegian ferroalloy and silicon carbide production.
� Increase the share of biological carbon (biocarbon) with 20 % in the Norwegian ferroalloy production within 2010.
Conclusion: Manganese research and possible cooperation between Norway and South Africa
� Due to FFF, manganese research have been carried out
at NTNU/SINTEF since early 1990’s
� Possibilities of exchange between university and industry
� New international master program in Silicon and Ferroalloys from 2008 which is an individual part of the Nordic International Master
34
2008 which is an individual part of the Nordic International Master Program
� Industry cooperation within safety and environment
� Fundamental research between academic institutions
and industry
Manganese Process Research 1990-2005Steering committee with members from Elkem/ERAMET - Tinfos - NTNU
� 8 PhD Thesis
� 3 ongoing PhD projects
� 22 Master Thesis
� 7 Post.docs - 14 man-labour years:
� 27 International Publications and 31 SINTEF-Reports (1990-2002).
35
� 27 International Publications and 31 SINTEF-Reports (1990-2002).
PhD Thesis - Silicon & Electric Arcs
� Andresen B: Process model for carbothermic production of silicon metal.
1995
� Ingason H: Hollow electrodes in the production process for ferrosilicon. 1994
� Valderhaug Aa. M: Modelling and control of submerged-arc ferrosilicon
furnaces. 1992
� Hildal K: Steam explosions during granulation of Si-rich alloys. Effect of Al-
and Ca-additions. 2002
� Liping G: Transport phenomena in silicon vapour infiltrated argon arcs and
36
� Liping G: Transport phenomena in silicon vapour infiltrated argon arcs and
anode metal pools. 1993
� Holt N: A metallurgical reactor with three plasma torches. 1994
� Larsen H L: AC electric arc models. 1996
� Sævarsdóttir G A: High current AC arcs in silicon and ferrosilicon furnaces.
2002
PhD Thesis - various related
� Ringdalen E: Production of High Carbon Ferrochromium, Reaction
Mechanisms. 1999
� Røhmen E: Thermal behaviour of a sperical addition to molten metals. 1995
� Eijk C : The nature and role of titanium containing oxide inclusions in steels.
1999
� Onsøien M I: Microstructure evolution in ductile cast iron containing rare
37
� Onsøien M I: Microstructure evolution in ductile cast iron containing rare
earth metals. 1997
� Skaar I M: Monitoring the lining of a melting furnace. 2001
Results of laboratory measurements have made it possible to determine:
� Slag/metal distribution equilibria for Mn and Si� Carbon solubility in various ferroalloys� Phase- and melting- relations of relevant slag and metal systems � Kinetics of Mn-ore reduction including catalytic effect of circulating
alkalies regarding the Boudouard reaction.� Relation between degree of ore pre-reduction, and consumption of
38
� Relation between degree of ore pre-reduction, and consumption of carbon and electric energy.
� Effect and importance of slag basicity� To develop a ferroalloy (Mn-Fe-Si-Cr-C) database for thermodynamic
calculations in the FACT-WIN computer program.� Raw material properties
� Mn ores
� Reducing agents
Metal/Slag/Gas Equilibrium RelationsMetal/Slag/Gas Equilibrium Relations
SiO2
50
60
70
8020
30
40
50
1500
o1550
o
1600
o
ThermodynamicsThermodynamics
39
MnO0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
CaO
60
70
80
90
100
Exp. 14500C
Exp. 15000C
Exp. 15500C
Exp. 16000C
Calculated
1400o
1450o
Metal/Slag/Gas Equilibrium RelationsMetal/Slag/Gas Equilibrium Relations
SiO2
50
60
70
8020
30
40
50
Cal., PCO=1atm
Cal., PCO=0.3atm
Exp. 1600oC, 1atm
Exp. 1550oC, 1atm
Exp. 1500oC, 1atm
Exp. 1450oC, 1atm
Exp. 1500oC, 0.3atm
CaO
/Al 2O
3=1.5
40
MnO0 10 20 30 40 50 60 70 80 90
10
20
30
40
50
C+A
50
60
70
80
90
CaO
/Al
Slag/Metal Equilibrium in FeMn ProductionSlag/Metal Equilibrium in FeMn Production
SiO
50
60
+C
aO
+M
gO
(w
t%)
40
50
Calculated
Exp., Si: <0.1%
Exp., Si: =0.1-0.5%
Exp., Si: 0.5-1.0%
Exp., Si: 1.0-2.0%
Exp., Si: 2.0-3.0%
41
MnO (wt%)
0 10 20 30 40 50 60 70 80 90 100
SiO
2 (wt%
)
0
10
20
30
40
Al 2O
3+C
aO
+M
gO
(w
t%)
60
70
80
90
100
CaO/Al2O
3=1.5, MgO/Al
2O
3=0.8
0.05%
0.1%
0.5%1.0%
2.0%3.0%
Slag/metalC-sat equilibrium
diagram
ThermodynamicsThermodynamics
42
Mn7Fe-Si-Csat alloys & MnO-SiO2-CaO-MgO-Al2O3 slags
18
20
22
A
β -SiC
Mn7Fe-Si-Csat
MnO-SiO2-CaO-MgO-Al
2O
3(CaO/MgO=2.5)
PTotal
= 1.0 atm
Si m
ass%
Si distribution between slag and metal in SiMn production
43
20 25 30 35 40 45 50 55 60
10
12
14
16
Graphite
84.02.01.0R=0.8
Si m
ass%
SiO2 mass%
ΣΣΣΣ Basic oxideR = ——————
Al2O3
Phase relatons: Liquidus content of MnO in FeMn slagversus slag basicity
MnO
(w
t%) 60
70
80
MnO-CaO-SiO2-Al2O3 slag
44
B=CaO/(Al2O
3+SiO
2)
0,0 0,2 0,4 0,6 0,8 1,0
MnO
(w
t%)
30
40
50
1450 oC
1500 oC
1550 oC
Al2O3/SiO2=0.5
A/S-ratio in range 0.25-0.5 of little importance
Replacement of CaO with MgO gives less MnO at liquidus
Smelt reduction Carbon
SlagEnergy
Metal
� Background� Research started with small
graphite crucibles
� Aim of Project� To utilise slag directly from the HC FeMn furnace
45
� To utilise slag directly from the HC FeMn furnace
� Produce SiMn directly
� Utilise the sensible heat of the slag
� Reduce handling and storage of HC FeMn slag
� Increase the productivity of SiMn furnace
� Less HC FeMn slag
� More Mn ore and quartz
� Possibly use less coke (different reductants)
Electrical conductivity in coke bedsPer Anders Eiden (2004-2008)
� Resistivity of beds of industrial carbon materials
� Parameters affecting the total resistance in coke beds
(experiments and modelling)
� (Geometry of cokebed – size and shape)
46
� (Geometry of cokebed – size and shape)
� Geometry of particles (incl. size)
� Packing (dependent on size and distribution)
� Type of carbon (coke, graphite, antracite,….)
� Inter-particle resistance
Electrical conductivity in coke bedsPer Anders Eidem (2004-2008)
47
Electrical conductivity in coke beds
48
Slag –Carbon reactivityJafar Safarian (2004-2007)
�MnO+C=Mn+CO(g)
�SiO2+2C=Si+2CO(g)M n-Fe-
Si-C sat
C O
bubbles
Slag
(SiO 2) + C O (g)
→ S iO(g) + C O 2(g)
C(gr.) + C O 2(g) → 2C O (g)SiO (g) + C →
Si + CO (g)
SiO(g)
transport
49
�Literature survey
�Wetting experiments
� Input to carbon characterisation method
G raphite
CO2 reactivityJakub Kaczorowski (2003-2006)
� Micro structure and other properties of
carbon materials
� Petrograpy (macerals and vitrinite
reflection)
Porosity and pore distribution
50
� Porosity and pore distribution
� Ash content and composition
� CO2 reactivity
� Carbon types, temperature, alkalies,
CO/CO2 ratio
� Industrial furnace sampling in prereduction
zone
CO2 reactivityJakub Kaczorowski (2003-2006)
� Coke from 3 single seem coals and 3 industrial cokes
51
CO2 reactivityJakub Kaczorowski (2003-2006)
Open pore distribution of Open pore distribution of
Polish and Australian single Polish and Australian single
seem cokesseem cokes
52
�� Thermochemical databases that have been Thermochemical databases that have been developed at SINTEF Materials Technology:developed at SINTEF Materials Technology:
�� AlAl--CaCa--CuCu--FeFe--MgMg--MnMn--SiSi--Zn system for the Zn system for the commercial Alcommercial Al--alloysalloys
�� MnMn--CrCr--FeFe--SiSi--CC--SS--P system for ferroalloysP system for ferroalloys
Thermotec -
53
�� MnMn--CrCr--FeFe--SiSi--CC--SS--P system for ferroalloysP system for ferroalloys
�� SiOSiO22--CaOCaO--AlAl22OO33--CrOCrO--CrCr22OO33--FeOFeO--FeFe22OO33--MgOMgO--MnO MnO oxide system for ferroalloy slagsoxide system for ferroalloy slags
�� Coupling thermochemical properties (databases) Coupling thermochemical properties (databases) with thermophysical properties (databases) : with thermophysical properties (databases) : density, viscosity, surface tension, ……density, viscosity, surface tension, ……
Phase Diagram for FeMn & SiMnPhase Diagram for FeMn & SiMn
6
7
8
9
10
univariant
isothermal
2300
2400o
M5C
2
C (
mass%
)
54
0 10 20 30 40
0
1
2
3
4
5
1050o
1100o
1150o
1200o
1250 o
1300 o
1400 o
1500 o
1600 o
1700 o
1800 o
1900 o
2000 o
2100 o
2200 o
2300o
M7C
3
Graphite
SiCββββ
M5Si
3
M3Siγγγγ-Mn
ββββ-Mn
εεεε-Mn
C (
mass%
)
Si (mass%)
Activity Activity -- Composition Relations of SiMn MeltsComposition Relations of SiMn Melts
0.5
0.6
0.7
0.8
0.9
1.0
Mn7Fe-Si-Csat
alloys
1400oC
1600oC
aC
Activity
55
0 5 10 15 20 25 30 35 40
0.0
0.1
0.2
0.3
0.4
0.5
aMn
aSi
Activity
Si mass%
The Max. Si% in MnSi by Carbothermic The Max. Si% in MnSi by Carbothermic
Reduction of MnO & SiOReduction of MnO & SiO22
30
40
Mn7Fe-Si-Csat
Alloys +
aSiO2
=0.2 Slags
PCO
= 0.33 atm
SiC+SiO
Mn-Si-Csat
Alloys +
SiO2-saturated Slags
Si m
ass%
1670o 1755o
56
1450 1500 1550 1600 1650 1700 1750 1800 18500
10
20
Mn7Fe-Si-Csat
Alloys +
SiO2-saturated Slags
SiC+SiO2
C+SiO2
Mn7Fe-Si-Csat
Alloys +
aSiO2
=0.2 Slags
Si m
ass%
Temperature oC
Equilibrium simulation results”reduction path” of raw materials
SiO2+Al
2O
3
60
70
80
90
1000
10
20
30
40
(Al2 O
(MgO
/CaO
=0.5
)
1500
o1550
o
5.0%10%
100-MnO-SiO2-Al2O3B = ——————————
SiO2+Al2O3
57
MnO0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
CaO+MgO
50
60
70
80
90
100
2 O3 /S
iO2 =
0.5
)(MgO
/CaO
=0.5
)
1350o
1400o
1450o
0.01%
0.1%
1.0%
5.0%
Metal/slag/gas Equ.
Metal/slag Equ.
Reduction path
B = 0.46B = 0.9
SiO2+Al
2O
3
50
60
70
80
90
1000
10
20
30
40
50
60(A
l2 O
3 /SiO
2 = 0
.57)(CaO
/MgO
= 2
.8)
Spinel
Mullite
Galaxite
Anorthite
58
MnO0 10 20 30 40 50 60 70 80 90
10
20
30
40
CaO+MgO
60
70
80
90
= 0
.57)(CaO
/MgO
= 2
.8)
(Mn,Ca, Mg, Al)Oss
Liquidus surface of the MnO-SiO2-Al2O3-CaO-MgO (Al2O3/SiO2=0.57, CaO/MgO=2.8) system
top related