Titanium in Chemical Process Industry
(CPI)
Suresh Divi
Corrosion Engineer
Titanium Metals Corporation (TIMET)
Process Corrosion Session
NACE Eastern Area Conference Oct. 7, 2009
Outline
•Introduction to the “CPI”
•CPI Equipment/Components
•Titanium Corrosion Resistance
•Titanium alloys
•Ti Applications in CPI
•Benefits & Cost considerations
•Ti role in the CPI
•Summary
Introduction to the “CPI”
•An industry in which the raw materials undergo chemical
conversion during their processing into finished products
•Chemical conversion influences the pH of the product
•Intern pH influences the corrosion resistance of the metal
•Very aggressive conditions (low pH, high temperature)
•In Petroleum refining, acidic conditions arise from chloride salts
entering the refinery in crude oil
•Dilute HCl acid encounter in many chlorination type chemical
process.Example: Manufacturing of Vinyl chloride monomer(VCM)
Typical CPI
•Power Generation
•Petrochemical
•Organic acid
•Chemical
•Fertilizers
•Metal Recovery
•Salt
•Chlorine
•Pulp & paper
CPI Equipment
•Heat Exchangers
•Reactor vessels
•Piping
•Pumps
•Mixers
•Anodes
•Anode baskets
•Distillation Columns
Titanium
•
•
•
•
•
•
Abundant - Not Exotic!
4th most plentiful metal on earth
Classified as a reactive metal (passive oxide film)
About half as dense as nickel
Similar in strength to 316 S.S. (CP Ti)
Excellent corrosion resistance/immunity in chlorides
(especially sea water)
• 45+ years service experience with the CPI
Ti Corrosion Resistance
•Corrosion protection is due to the formation of oxide film
•Thin (100Å) and transparent
•Stable and chemically resistant
•Smooth and ceramic like, hard to remove
•Instantaneously reheal after damage
(needs traces of water or oxygen)
Titanium Corrosion Resistance
•Anodic Protection (external power supply)
•Inhibitors (Fe+3, Cu+2, Mo+6,etc..)
•Alloying with stable elements (Mo,Zr ,Cr)
•Alloying with noble metals (Pt,Pd,Ru)
•Very resistant to oxidizing media (HNO3)
Titanium Corrosion Resistance
Wide range of
passivation
Titanium Corrosion Resistance
•Excellent resistance to chloride corrosion (pitting)
•Immune to soil & atmospheric corrosion
•No preferential weld corrosion
•Immune to MIC (microbial influenced corrosion)attack
•Good resistance to Erosion
•No corrosion in Sea water
Titanium alloys
Titanium & Titanium Alloys for the CPI Market
ASTM
ASTM
GRADE
ASTM
GRADE
ASTM
GRADE
GRADE
1
1
1
2
1
2
27
27
16
7
16
7
16
3
16
3
3
12
3
12
12
9
12
9
9
32
9
32
32
5
32
5
5
23
5
23
23
23
TIMET
TIMET
DESIGNATION
TIMET
DESIGNATION
TIMET
DESIGNATION
DESIGNATION
TIMETAL@
35A
TIMETAL@ 35A
TIMETAL@ 35A
TIMETAL@ 35A
50A
TIMETAL@
TIMETAL@ 50A
TIMETAL@ 50A Pd
TIMETAL@ 50A Pd
05Pd
TIMETAL@
TIMETAL@ 50A
50A Pd
05Pd
TIMETAL@
TIMETAL@ 50A
50A Pd
05Pd
TIMETAL@
TIMETAL@ 65A
50A 05Pd
TIMETAL@ 65A
TIMETAL@ 65A
TIMETAL@
TIMETAL@ CODE
65A 12
TIMETAL@ CODE 12
TIMETAL@ CODE 12
TIMETAL@
TIMETAL@ 3-2.5
CODE 12
TIMETAL@ 3-2.5
TIMETAL@ 3-2.5
TIMETAL@
TIMETAL@ 5111
3-2.5
TIMETAL@ 5111
TIMETAL@ 5111
TIMETAL@
TIMETAL@ 6-4
5111
TIMETAL@ 6-4
TIMETAL@ 6-4
TIMETAL@ 6-4
6-4 ELI
TIMETAL@
TIMETAL@ 6-4 ELI
TIMETAL@ 6-4 ELI
TIMETAL@ 6-4 ELI
NOMINAL
NOMINAL
COMPOSITION
NOMINAL
COMPOSITION
NOMINAL
COMPOSITION
COMPOSITION
Unalloyed
Titanium
Unalloyed Titanium
Unalloyed Titanium
Unalloyed Titanium
Titanium
Unalloyed
Unalloyed Titanium
Ti-0.15Pd Titanium
Unalloyed
Ti-0.15Pd
Unalloyed
Ti-0.05Pd Titanium
Ti-0.15Pd
Ti-0.05Pd
Ti-0.15Pd
Ti-0.05Pd
Unalloyed
Ti-0.05Pd Titanium
Unalloyed Titanium
Unalloyed Titanium
Ti-0.3Mo-0.8Ni
Unalloyed Titanium
Ti-0.3Mo-0.8Ni
Ti-0.3Mo-0.8Ni
Ti-3Al-2.5V
Ti-0.3Mo-0.8Ni
Ti-3Al-2.5V
Ti-5Al-1Sn-1Zr-1VTi-3Al-2.5V
Ti-5Al-1Sn-1Zr-1V0.8Mo-0.1Si
Ti-3Al-2.5V
Ti-5Al-1Sn-1Zr-1V0.8Mo-0.1Si
Ti-5Al-1Sn-1Zr-1V0.8Mo-0.1Si
Ti-6Al-4V
0.8Mo-0.1Si
Ti-6Al-4V
Ti-6Al-4V
Ti-6Al-4V-0.1O
Ti-6Al-4V
Ti-6Al-4V-0.1O
Ti-6Al-4V-0.1O
Ti-6Al-4V-0.1O
UNS
UNS
DESIG.
UNS
DESIG.
UNS
DESIG.
DESIG.
R50250
R50250
R50250
R50400
R50250
R50400
R52400
R50400
R52400
R50400
R52402
R52400
R52402
R52400
R52402
R50550
R52402
R50550
R50550
R53400
R50550
R53400
R53400
R56320
R53400
R56320
R56320
R55111
R56320
R55111
R55111
R56400
R55111
R56400
R56400
R56407
R56400
R56407
R56407
R56407
ALLOY
ALLOY
TYPE
ALLOY
TYPE
ALLOY
TYPE
TYPE
Alpha
Alpha
Alpha
Alpha
Alpha
Alpha
Alpha
Alpha
Alpha
Alpha
Alpha
Lean
Alpha
Lean
Alpha/Beta
Lean
Alpha/Beta
Lean
Lean
Alpha/Beta
Lean
Alpha/Beta
Alpha/Beta
Lean
Alpha/Beta
Lean
Lean
Alpha/Beta
Lean
Alpha/Beta
Alpha/Beta
Lean
Alpha/Beta
Lean
Lean
Alpha/Beta
Lean
Alpha/Beta
Alpha/Beta
Lean
Alpha/Beta
Lean
Alpha/Beta
Alpha/Beta
Alpha/Beta
Alpha/Beta
Alpha/Beta
Alpha/Beta
Alpha/Beta
Alpha/Beta
Alpha/Beta
Alpha/Beta
CREVICE
CREVICE
THRESHOLD
CREVICE
THRESHOLD
CREVICE
THRESHOLD
THRESHOLD
80-90C
80-90C
80-90C
80-90C
80-90C
80-90C
80-90C
>250C
80-90C
>250C
>250C
>250C
80-90C
80-90C
80-90C
~150C
80-90C
~150C
~150C
80-90C
~150C
80-90C
80-90C
80C
80-90C
80C
80C
80C
80C
80C
80C
80C
80C
80C
80C
80C
MECH
MECH
STR
MECH
STR
MECH
STR
STR
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Medium
Medium
Medium
Medium
Medium
Medium
Medium
Medium
Medium
Medium
Medium
High
Medium
High
High
High
High
High
High
High
High
High
High
High
FEATURES
FEATURES
FEATURES
Most formable
grade-for
FEATURES
Most
formable
cladding & PHEgrade-for
Most
formable
cladding
& PHEgrade-for
Most
widely
used
titanium
Most
formable
grade-for
cladding & PHE
Most
widely
used
grade-best
comb. titanium
of props
cladding
& PHE
Most
widely
used titanium
grade-best comb.
of props
Added
corrosion
Most
widely
usedresistance
titanium
grade-best
comb.
of props
Added
corrosion
over
grade
2comb.resistance
grade-best
of props
Added
corrosion
resistance
over grade
2
Added
corrosion
resistance
over grade
2
over
grade
2
Added
strength
vs grade 2
Added strength vs grade 2
Added
Added corrosion
strength vsresistance
grade 2
Added
corrosion
&
strength
vs grade
2
Added
strength
vsresistance
grade
2
Added
corrosion
resistance
& strength vs grade 2
Cold
formable,
med.
Added
corrosion
resistance
& strength
vs grade
2
Cold
formable,
med.
strength
titanium
alloy
& strength vs grade
2
Cold
formable,
med.
strength
titanium
alloy
High
Cold toughness/weldable
formable,
med.
strength
titanium
alloy
High
toughness/weldable
alloy
for
plate/fasteners
strength titanium alloy
High
alloy toughness/weldable
for plate/fasteners
Std.
alloy-some SCC
High aero
toughness/weldable
alloy
for plate/fasteners
Std.
aero
alloy-some
concerns
in sea waterSCC
alloy for plate/fasteners
Std.
aero
alloy-some
concerns in sea waterSCC
Low
oxygen
grade
5-no
Std.
aero alloy-some
SCC
concerns
in sea
water
Low
oxygen
grade
5-no
SCC but lower
concerns
in seastrength
water
Low
grade
5-no
SCCoxygen
but lower
strength
Low
oxygen
grade
5-no
SCC but lower strength
SCC but lower strength
Titanium alloys
Mechanical Properties
160
Tensile
Yield
Elongation
140
120
1240
High
1100
965
Medium
825
100
690
Low
80
550
60
415
40
275
20
138
0
0
1
2
3
12
9
32
ASTM Titanium Grade
23
5
Typical Strength (MPa)
Typical Properties (ksi or %)
180
Titanium alloys
Low Strength Grades (1, 2, 7, 11, 16, 17)
• Grade 2 most readily available
• Strength similar to austenitic SS
• Pd/Ru does not affect mechanical props
Medium Strength Grades (3, 12, 9, 28)
• Can be cold formed (strip producible)
• Available in all product forms
• Strength similar to duplex SS
• Highest strength ASME grades
High Strength Grades (23, 29, 32, 5)
• Common product forms are bar/billet/plate
• Must use heat when forming
• Weldability is best in grade 32
• Oxygen/Al content affect toughness and SCC
Titanium alloys-Reducing acids
50
Corrosion
Rate (mpy)
40
(1mm/yr)
Grades 1-3 Ti
Grade 9 Ti
Grade 5, 23, 32 Ti
30
Grade 12 Ti
20
(.5mm/yr)
Grade 16, 17 Ti
10
5mpy
(.127mm/yr)
Grade 7, 11 Ti
0
0
pH 1
1
2
3
pH 0
Boiling HCl Concentration (w t.%)
4
5
6
Localized Corrosion
14 -
General Guidelines for Crevice Corrosion Resistance of
Titanium in NaCl Brine Media
pH
Grades 1, 2, & 3
7-
Crevice corrosion possible
Grade 12
Pd Grades 7 & 16
00
150
Temperature (ºC)
• Not susceptible to pitting or SCC attack (unalloyed grades)
• All Ti grades resistant to crevice attack to about 80°C
• Other grades (especially Pd) can be used up to >250°C
300
Corrosion - Galvanic Effects
• Ti very noble in chlorides - almost always
the cathode
• Since Ti is cathode, no concern for corrosion
• In galvanic couple, other metal may have
accelerated corrosion attack
• Hydrogen damage to Ti may occur if cathodic
potential not regulated and if temperature >
80ºC
CPI companies use Ti
•Dow,Dupont
•Shell, Chevron, BP (AMOCO)
•Morton Salt
•Kerr-McGee
•Bayer
•Heinz
•BASF
Ti application in CPI
Reactor Vessel
Ti lined reactor vessel for mining operation
Ti application in CPI cont..
Tube Exchanger
Straight heat tube exchanger
Ti application in CPI cont..
Tube Exchanger
Plate coil immersion heat exchanger
Plate heat exchanger
Ti application in CPI cont..
Ti tubed salt evaporator for table salt
Ti application in CPI cont..
Ti anode baskets for anodized metal parts
Benefits-Corrosion Resistance
(Sea Water)
Corrosion Mode
Cu
Alloys
Al
Alloys
316
SS
Adv.
SS
Ni
Alloys
Titanium
General Corrosion
R/S
R
R
R
R
R
Erosion Corrosion
S
R
R
R
R
R
Pitting Attack
S
S
S
R
R
R
Crevice Corrosion
S
S
S
S
S
R
Stress Corrosion
R/S
S
R/S
R
R
R
MIC
S
S
S
S
R
R
Weld Attack
S
S
S
S
R
R
Galvanic Attack
S
S
S
R
R
R
Composite Comp.
S
S
S
S
S
R
S=Susceptible
R=Resistance
Benefits-Corrosion Resistance
(Performance)
Maximum Performance







Minimum Performance

Titanium ASTM Grades 7 & 16
Titanium ASTM Grade 12
Titanium ASTM Grade 2 / Alloy C-276, C22, 59
Alloy 625
6 Mo Stainless Steel / 2507 Stainless Steel
2205 Stainless Steel
316L Stainless Steel
304 Stainless Steel
Galvanic series-Sea water
Ti application
Sea water application
Centrifugal pumps
Ti application
Sea water application
Cast pump for handling sea water
Benefits-Density
•Roughly half as dense as iron & nickel based alloys
•A pound of titanium goes a lot further
Titanium
Zirconium
Stainless
Steel
Nickel
Copper
Benefits
Good Thermal Conductivity (12.5 Btu/Hr-Ft2-°F/ft)
•30% above 300 series Stainless steel,
•60% above the super stainless grades
Low Elastic Modulus (15 Mpsi)
•Titanium flexibility considered into design and fabrication
(supports,shafts)
Life cycle
•Ti wins life cycle costing and proper design engineering
(thin wall, no corrosion allowance)
Benefits-Design Allowance
ASME Design Allow./Unit Density
(ksi/lb/cu in)
160
140
Grades 2,7&16Ti
120
Grade 3Ti
100
Grade 12Ti
Grade 9Ti (Gr18)
80
316L SS
60
Alloy 625
40
C-276
20
0
0
100
200
300
400
Temperature (°F)
500
600
700
Cost considerations
Total system installed cost & maintenance
•Eliminate multiple installation/replacement costs
•Reduced maintenance costs (oxide forms “slick” surface)
•Titanium does not require coatings
•Environmental/contamination costs (Ti non-toxic)
•Reuse/recycle of Titanium
Ti role in the CPI
Mature Applications >30 yrs service history
Industry
Typical Areas
Titanium Equipment
Date of First Use
Organic acid production
Chlor-Alkali
Salt production
Chlorinated Hydrocarbons
Heat exchangers, reactors,
columns, piping, anodes
Early 1960's
Crude Overheads
Desulfurizing
Process cooling water
Heat exchangers, piping
Late 1960's
Plating
Electrowinning
Hydrometallurgical
Anodizing
Anodes, cathodes, baskets,
drums, heaters, exchangers,
agitators, piping
Late 1950's to early
1960's
Waste Treatment
WAO
Heat exchangers, autoclaves
Early 1970's
Pulp/paper Mills
Bleach plant
Mixers, diffusion washers
Mid to late 1950's
Chemical Plants
Refineries
Metal Finishing
Ti role in the CPI
Newer Applications <20 yrs service history
Industry
Typical Areas
Titanium Equipment
Use Date
Chemical/Refinery
Mature + new
processes/conditions
Piping, tubing, advanced
grade selection
Ongoing
Metals' Production
Nickel Laterites
Cu Anodes
Clad vessels, piping, tubing,
anodes, misc. equip.
90's
Late 80's
Geothermal
Service water
Nuclear waste-Yucca Mt.
CP & Alloy piping, vessels,
formed plate
Mid 90's
Late 80's
????
Oil & Gas
Production Piping
Fire water piping
Alloy + CP piping, alloy
sheet/billet
Water Treatment
SCWO
RO Units
Piping, Heat exchangers
Power Generation
90's
???
90's
SUMMARY
• Excellent chloride corrosion resistance
• Wide selection of alloy properties without
sacrificing corrosion resistance
• Proven resistance to many organic chemicals
• Environmentally friendly metal
• Cost effective for CPI equipment
• >40 years proven service in the CPI