Warren Scott - Viva Energy Australia - Trials and results for a new gas turbine oil
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Transcript of Warren Scott - Viva Energy Australia - Trials and results for a new gas turbine oil
14/01/2016 Shell trademarks used under licence
Innovative Lubricating
Solution For Gas Turbines
Gas Turbine Users Forum
Sydney
November 25 2015
Warren Scott- Lubricants Specialist
24/01/2016Copyright of Shell Lubricants
TODAY’S TURBINES HAVE TO WORK HARDER
THAN EVER BEFORE
Affects the turbine oil
Increased operating temperatures drive
requirements for greater component protection
Turbine sump volumes are shrinking in size while handling the same or
increased power
Greater demand for less downtime, extended oil-
drain intervals and efficiency improvements
Environmental legislation continuously driving towards lower
emission levels
Increased pressure on gearboxes
Cyclic operating conditions are placing
more stresses on turbines
2
34/01/2016Copyright of Shell Lubricants
OIL STRESS HAS INCREASED BY 400% AND
OPERATING TEMPERATURES ARE HIGHER
3
Increasing oil stress and operating temperatures*
8C GE fr 5 GE fr 6A GE fr 6B GE fr 9E
80
70
60
50
40
30
20
10
0
12
0
10
8
6
4
2
Oil stress index, MW m-3 Oil temperature, °C
Oil
stre
ss in
dex
, MW
m-3
Oil
tem
per
atu
re, °
C
*Shell calculation based on publically available data
44/01/2016
Why the lubricant is important – reliability
• Turbine reliability requires
– Prevention of metal-to-metal
contact in hydrodynamic
lubrication regime and control
valve sticking both during start
up and shut down and across
the range of operating
temperatures
– Cooling to prevent rapid oil
degradation and the formation
of bearing deposits
– Corrosion protection for the
main bearings and system
components
..Shell Turbo
54/01/2016Copyright of Shell Lubricants
WHY THE LUBRICANT IS IMPORTANT –
EFFICIENCY
Deposit build-up on metal surfaces
64/01/2016
Why the lubricant is important – efficiency
• Turbine system efficiency is affected by
..Shell Turbo
The formation of
emulsions
Excessive foam in the
turbine reservoir
Deposit build-up on
metal surfaces
74/01/2016
TYPICAL TURBINE OIL COMPOSITION
R&O
Additive
System
< 1-2%
Base Oil
98-99%
Antioxidants
Rust Inhibitor
Corrosion Inhibitor
Others *
Turbine oil additive system
* Defoamer, demulsifier, AW/EP additives (where required)
Group Typical Process Route Sulphur (Wt %) Saturates (Vol %)
Viscosity Index
I Solvent refining > 0.03 &/or <90 ≥ 80 – < 120II All-Hydro-processing ≤ 0.03 & ≥ 90 ≥ 80 – < 120III All-Hydro-processing ≤ 0.03 & ≥ 90 ≥ 120IV Synthetic Poly-Alpha-Olefins (PAO)
V Other Base Oils Not Group I, II, III or IV
84/01/2016Copyright of Shell Lubricants
GAS-TO-LIQUIDS (GTL) BASE OIL
TECHNOLOGY
•Catalytic process converting gas to oil products
8
API group III+ base oil
Primarily iso-paraffinic, no impurities, excellent antioxidant response, surface properties, narrow molecular distribution
GTL base oil
94/01/2016Copyright of Shell Lubricants
INNOVATIVE TURBINE OILS BASED ON GTL
TECHNOLOGY
•High performance turbine oils to:
– Meet the demands of the latest high-
efficiency turbine systems
– Offer outstanding, long-term performance
under the most severe operating
conditions
– Help to minimise deposit formation, even
under cyclic peak loading.
The use of GTL technology enables
performance enhancements in the area
of:
– High viscosity index
– Rapid air release
– Foaming resistance
– High flash point
– Rapid water separation
9
104/01/2016Copyright of Shell Lubricants
DEPOSIT FORMATION TENDENCY – ASTM D7873
DRY TURBINE OIL STABILITY TEST (DRY TOST)
•1,008 hour Dry TOST (ASTM D7873)
Oxidation of the fluid is promoted by
heat, in the presence of oxygen and
metals (copper and steel coils), no
water
Measure RPVOT and oxidation
products (sludge) after 1,008 hours
10
Test Conditions• Temperature 120ºC (248ºF)• Copper and steel catalyst• Evaluate the sample at 1008 hrs
Assesses the sludge tendency by measuring insoluble oxidation products and RPVOT retention
114/01/2016Copyright of Shell Lubricants
DEPOSIT FORMATION TENDENCY – ASTM D7873
DRY TURBINE OIL STABILITY TEST (DRY TOST)
11
Testing based on commercially obtained samples
0
200
400
600
800
1000
Turbo S4 Oil A Oil B Oil C Oil D Oil E
Slu
dg
e, m
g/k
g
Dry TOST Evaluation at 1008 hrs (D7873)
4000
5000
Bet
ter
Pe
rfo
rman
ce
GtL-based Oil
124/01/2016Copyright of Shell Lubricants
Static Oven = 180ºC (356ºF)Test Time = 48 hoursAir Flow = NoneMetal Catalysts = None
Measurable:
– Sludge, mg/kg
– Volatility of base oil and formulation
OXIDATION STABILITY AND DEPOSIT CONTROL
MAN-LTAT (LUBRICANT TEMPERATURE AGING TEST) AT 180°C
12
This thermal stability test assesses the oil’s short term deposit resistance whenexposed to very high temperatures.
The test result indicates the oil’s resistance against sludge formation and is key toobtaining MAN Turbo approval.
The lower the sludge levels in the oil at the end of test the better the performance.
134/01/2016Copyright of Shell Lubricants
PREVENTING CRITICAL COMPONENT FAILURE &
UNPLANNED SHUTDOWNS
13Shell Turbo
• The long-term resistance to formation of sludge and varnish deposits of GtL-
based turbine oil helps reduce the risk of bearing temperature issues and
control valve positioning problems, which can upset running stability and
cause turbine trips.
GtL-based oil performs much better than other oils
tested in the MAN-LTAT oxidation test (beaker test)
0
500
1,000
1,500
2,000
Shell TurboS4
Oil A Oil B Oil C Oil D Oil E
Slu
dge
, mg
MAN-LTAT oxidation test (beaker test) at 180°C*
*Source: Shell test data
GtL-based Oil
Bet
ter
Pe
rfo
rman
ce
144/01/2016
EFFICIENCY BENEFITS OF API GRP iii BASED
TURBINE OILS
• Turbine oil formulated with GTL base oil provide a higher inherent viscosity
index and lower friction coefficient relative to turbine oils formulated with
API Grp I or Grp II base oils
• Provides a thicker lubricating film at higher operating temperatures versus
conventional GP I/II (lower VI) based oils of the same ISO grade
.
--- GTL Based Turbine Oil
--- Converntional API Grp II Turbine Oil
174/01/2016Copyright of Shell Lubricants
EFFICIENCY BENEFITS OF GTL BASED TURBINE
OILS AIR RELEASE AND FOAMING
•Turbine oil reservoirs are circulating oil system and entrainment of air
and foaming is possible
•Important to consider residence time of oil in tank to help settle
contaminants (including air, water)
•Turbine oils formulated with GTL base oils can significantly improve air
release times and reduce foaming potential
184/01/2016Copyright of Shell Lubricants
EFFICIENCY BENEFITS OF GTL BASED TURBINE
OILS AIR RELEASE AND FOAMING
– Poor air separation properties leads to:
Adiabatic compression within the oil (micro-dieseling), acidic contaminants, rapid
decrease of the antioxidant system and an increase in oil insoluble material
– Operational difficulties due to poor air separation include:
Cavitation, loss of oil pressure, reduced oil flow, poor response in high pressure
servos, filter blocking
– Use of turbine oils formulated with GtL base oils show an outstanding air
separation properties leading to:
Reduced maintenance cost, increased turbine reliability, extended oil life, higher return
on investment, peace of mind
18
194/01/2016Copyright of Shell Lubricants
PROACTIVE TURBINE OIL MONITORING
– Turbine oil condition monitoring is
critical
– Important to use an oil analysis
testing programme that includes
targets, warning limits and frequency,
with diagnosis and recommended
actions
1904 January 2016Shell Turbo
204/01/2016
Summary
– Turbine oils play a critical role in the availability and reliability of turbines
used in the power generation, oil & gas and heavy industry sectors
– In response to field issues, OEMs and industry bodies are developing
increasingly differentiated turbine oil requirements with a focus on
longer life and reduced deposit forming tendencies
Innovation in turbine oil technology such as the use of Gtl
technology based oils in Shells new Turbo S4 X/GX range allows
operator needs to be met
. .
214/01/2016
SHELL TURBO S4 SERIES: FIELD EXPERIENCE TO
DATE
224/01/2016
Current Usage of Turbo S4 X 32 & S4 X46 Shell Turbo S4 X 32 Location Equipment Start Notes
Shell Technology Centre Houston USA Solar Taurus C 60 GT Since 2012
Drain and fill
Dominion Energy USA GE Frame 7 FA GT Since 2013 Replace Texaco GT 32 – drain and fill
Shell Canada Scotford Canada Elliott PAP Compressors x 5 Since 2014
Replace Turbo SG 32 – drain and fill
Shell Canada Scotford Canada Sundyne Compressor x2 Since 2014
Replace Turbo SG 32 – drain and fill
Spectra Energy USA Solar Centaur GT Since 2015 New start-up
Empire District Energy USA
Siemens-Westinghouse 1426RT2 Steam Turbine Since 2015
Conversion from Mobil DTE 732
234/01/2016
Current Usage of Turbo S4 GX 32/46 Shell Turbo S4 GX Location Equipment Start Notes
Stadtwerke Rostock Germany ABB V32A Steam Turbine Since 2015
Drain and fill
Stadtwerke Rostock Germany Siemens SGT 600 GT Since 2015 Drain and fill
Vattenfall Germany Siemens GT Since 2015 Top off – Shell Turbo CC 46
EDF France GE Frame 9FHA Since 2015 Initial fill new combined cycle
EDF France GE D14 Steam Turbine Since 2015 Initial fill new combined cycle
Samsung (EPC)Saudi-Arabia MAN Turbo-
CompressorSince 2015
Initial fill new project
244/01/2016
Dominion Energy
First field trial candidate selected in US
Heavy duty gas turbine GE frame 7 FA
Power Generation service
Product: Shell TURBO S4 X 32
Field trial started mid April 2013
In service > 2 year with Shell Turbo S4 X 32
• Peaking Power Plant - low operational hours (~2,628)
• Peaking and cylic duty is more severe on lubricant performance than base
load - Starts= 279
– Overall oil condition very good
• No filterability or servo valve varnish issues
• Good foaming & water separation characteristics
• Air release < 2 minutes
• MPC < 10; RPVOT retention >95% (1426 minutes)
© Shell Global Solutions International B.V,; 2015, All rights reserved
254/01/2016