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1
Valve Requirements in the
Oil Sands
- Specifications and Learnings in a Mining and Upgrader Operation
Brian A. Lade, P.Eng.
Syncrude Canada Ltd.
2
Valve Requirements in the Oil Sands
- Specifications & Learnings in a Mining
and Upgrader Operation
Abstract: This presentation outlines the wide range of valve types, sizes and metallurgies needed within an integrated, self-contained Oil Sands operation that includes utilities, mining, bitumen capture and cleaning, upgrading the bitumen to form light sweet synthetic crude oil, and the safe management of waste streams. Quality and reliability challenges and trends are highlighted.
3
Who I am: • Brian Lade, P.Eng.
• Senior Technical Specialist –Mechanical Quality Advisor, Technical Quality Assurance
• Licensed Professional Engineer in Alberta Canada since 1978.
• Employed by Syncrude Canada Ltd. since 1975, with a career focused on pressure equipment/ process plants in Design, Maintenance, Operations, Quality Assurance and in Project Development and Execution roles in a variety of technical specialist and leadership positions. Current “owner” of key Specifications and AML’s for pipe, piping components and valves.
• Seconded to Alberta Government in late 1990’s for 2 ½ years for legislative updates and oversight of the ABSA.
4
View of Syncrude Mildred Lake Complex
during UE-1 Project Construction
5
Views of Aurora North plants
6
Integrated, self-contained and complex
• Syncrude is basically self-sufficient except for
importing natural gas and a range of chemicals;
and for the intake of fresh water.
• Our facilities are designed to operate 24/ 7/ 52 in
an ambient environment that demands a design
temperature range of – 56 oF to 92 oF, with approx.
7 months of ‘winter’ resulting in a frost depth >10 ft.
• We internally generate BFW, steam and hot water;
produce compressed air, nitrogen and hydrogen;
create and process fuel gas; and generate
electricity to match our operating needs.
7
Integrated, self-contained and complex
• We mine Oil Sands within 2 mining sites with most of the feed converted near the mine face to a warm water slurry in 6 crushing & preparation trains.
• Separation and capture of the bitumen takes place adjacent to each mine area; and then the bitumen is combined, heated & thinned with diluent, and cleaned in a single large facility.
• Bitumen Upgrading requires separating and recycling the diluent, changing the ratio of carbon to hydrogen, and in breaking up the complex long-chain molecules.
• Syncrude uses 3 Fluid Cokers, a large Vacuum Tower, a Fluidized Bed Hydrocracker, and 6 Hydrotreaters to accomplish those tasks.
8
Integrated, self-contained and complex
• Our diluent is naphtha. Newer bitumen production complexes typically use imported NGL/condensate fluids for internal bitumen processing and for pipeline transport. Many of their valves must then deal with the associated increase in volatility/ RVP in their stem seal designs and in leak tightness.
• Other Upgraders, whether integrated or stand-alone, may use multiple trains of Delayed Cokers, or use Fluidized Bed Hydrocrackers to lighten and desulphurize their products.
• Auxiliary process units treat fuel gas, wash SO2 & H2S from the fluids, treat sour water, clean flue gas, transfer heat between units and sites, etc. Other units process byproducts – liquid sulphur, coke, ammonium sulphate fertilizer, and gypsum.
9
Integrated, self-contained and complex
• Provision of an initial level of redundancy for reliability, and then staged growth for 3 decades has produced a central complex of 53 process units at Syncrude’s Mildred Lake site; along with 30 large storage tanks providing ~ 12 M BBls of hydrocarbon storage.
• Our last major growth step (2000 – 2005) was a
> $ 7.5 Billion project called UE-1, which added 20 new process units including the largest Fluid Coker and Hydrogen plants ever built; and the revamp/ upsizing of another 20 process units.
• That project purchased ~ 42 k Manual (Isolation) valves. Analysis of those purchases is a key basis for this presentation.
10
Complexity and Size both matter
Integrated Utilities including:
• 7 large Boilers and 2 OTSGs for 4.3 M PPH 900# Steam and 3.2 M PPH 600# Steam
• 6 STGs & 4 GTGs, generating up to 525 MW of power [Equiv. to a city of 300+ k]
• 12 trains of BFW production generating ~ 9000 GPM
• Hot Recycle/ Process Water > 140 k GPM in pipes running to NPS 48
• 4 Cooling Water Systems totaling ~ 380 k GPM in pipes up to NPS 72
• 5 Flare Systems with Headers at NPS 20 to NPS 54
11
Unprecedented Process Unit Sizes
• Diluted Bitumen cleaning capacity of 900 k BPD using a complex of > 120 Static and Centrifuge Separators for water, clay, and sand removal
• Upgrader feed capacity (Heating and Diluent Recycle Units) sized at 850 k BPD
• 3 Fluid Cokers (thermal cracking & carbon removal) at 50 psig/ >1200 oF, sized at 100 k BPD each
• A Fluid Bed Hydrocracker (cracking & hydrogen addition) at 1700 psig & 1000 oF, 50 k BPD
• One Vacuum Distillation Unit at 285 k BPD
12
Unprecedented Process Unit Sizes
• 2 Naphtha Hydrotreaters at 600 psig, 48 k BPD
• 2 Heavy Gasoil Hydrotreaters at 1500 psig, 78 k BPD
• A Light Gasoil Hydrotreater at 1700 psig, 100 k BPD
• A two stage Light Gasoil Hydrotreater/ ASU at 2500 psig, 80 k BPD
• 4 Steam–Methane Reformers generating > 400 M scfm of Hydrogen, with the newest unit being the worlds largest at 200 M scfm
13
Valves used in Syncrude
7,000 Pressure Safety Valves
15,000 Control Valves, Dampers and Large Actuated Isolation Valves
> 150,000 Manual (Isolation) Valves
• Both the PSVs and the Control Valves are individually numbered and are managed within a database. A size analysis for the Control Valves is included in this presentation.
• The breadth & characteristics of the Manual/ Isolation Valve population is illustrated by analysis of the UE-1 purchases which represented approx. 25 – 30 % of today’s estimated in-service population.
14
Control Valve Population
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1400
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Valve Sizes ( in Inches)
Control Valve Size Distribution (ALL Classes & Metallurgies)
15
Control Valve Population
• CV population reflects pressure classes and metallurgy selections that are described in more detail for the Isolation Valves in the slides which follow
• Quality requirements also follow a logic that is similar to that used for the Isolation Valves, but with an additional shift towards RT verifications based on typical low volume purchases & fabrication
• NPS 24 to 30 population is predominately Knife-gate valves used in slurry services; many are a specialty product with hydraulic actuators controlling Y- type branch
isolations • This valve population starts to add Isolation services as
size and dP combine to require automation.
16
Isolation Valve population
• 68 % forged, but only 13 % of $ value
• 32 % cast, but 86 % of $ value
MANUAL ISOLATION VALVES - FABRICATION METHODS
FORGED VALVES
68 % 28,801 items
CAST VALVES
32% 13,396 items
UE-1 Project - 42,197 Valves
Purchased
17
Isolation Valve population
NOTES:
• Small globes are most often used to isolate drains & small branches in HP services
• For Class 2500 services almost all valves are globes
FORGED VALVES
- FUNCTION SPLITS
GATE VALVES
89 %
GLOBE VALVES
8 %
CHECK VALVES
3 %
18
Isolation Valve population
• 87 % of cast valves are Carbon Steel, with just 5.6 % being Low Temperature Spec LCC
• Remainder are split between Low Alloy [1 ¼ Cr, 5 Cr & 9 Cr], and
Stainless Grades [304H, 316, 317L, 347 and 347H, and Duplex SS], and High Alloys 625, 825, C-276, and Alloy 59.
CAST VALVES
- FUNCTION SPLITS
GLOBE VALVES
5 %
CHECK VALVES
10 %
GATE VALVES
85 %
19
Isolation Valve population
• MPI/ LPI are the primary Quality requirements with ~ 3 % ordered
to RT verification levels per criticality of service locations
0
200
400
600
800
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2.0" 2.5" 3" 4" 5" 6" 8" 10" 12" 14" 16" 18" 20" 24" 28" 30" 36" 42" 48"
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Valve Size in Inches
Size Distribution for CLASS 150 Cast CS Valves
Class 150 CAST CS WCB
Class 150 CAST CS LCC
20
Isolation Valve population
• Larger sizes transition to automated Control Valve population
• MPI/ LPI continue as the primary Quality requirements with ~ 9.5 %
ordered to RT verification levels
0
200
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600
800
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2.0" 2.5" 3" 4" 5" 6" 8" 10" 12" 14" 16" 18" 20" 24"
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Valve Size in Inches
Size distribution for CLASS 300 Cast CS Valves
Class 300 CAST CS WCB
Class 300 CAST CS LCC
21
Isolation Valve population
• Quality requirements shift to addition of 100 % RT verifications
(partial or full), and many are ordered to ISS spec
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VALVE SIZE in INCHES
CLASS 600 CAST CS VALVES
RF (Quality Level- Full RT)
RTJ (Quality - 95% Partial RT, 5% Full)
22
Isolation Valve population
• RT level shifts from 60% Full RT for 900# to 85% Full RT for
1500#, with similar shift to ISS spec
0
10
20
30
40
50
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70
80
2.0" 2.5" 3" 4" 5" 6" 8" 10" 12"
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VALVE SIZES in INCHES
CLASS 900 CAST CS VALVES
900# BW & PSB (Full RT)
900# BW & PSB (Partial RT)
23
Isolation Valve Population
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40
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120
140
2.0" 2.5" 3" 4" 5" 6" 8" 10" 12"
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Item
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VALVE SIZES in INCHES
CLASS 1500 CAST CS VALVES
1500# CAST CS (Partial RT)
1500# CAST CS (Full RT)
24
Isolation Valve population – Manual Globes
• Valve population is slightly biased as using them as CV bypasses is reduced
at ~ NPS 8 as costs increase
Pressure Class Distribution for Manual Globe Valves
CLASS 150
180 Items, 37.5%
CLASS 300
212 Items, 44.3%
CLASS 600
45 Items, 9.4%
CLASS 900
15 items, 3.1 %
CLASS 1500
27 items, 5.6%
25
Isolation Valve population
Pressure Class Splits for ALL Cast CS Valves
150# WCB
150# LCC
300# WCB
300# LCC
600#
900#
1500#
46.7%
4.5%
34.4%
1.8%
8.2%
2.2% 2.2%
26
Highlights from Specifications
• LCC & LF2 Cl.1 use is surprising small. Most Oil Sands fluids are winterized or are heated to reduce viscosity (insulation & steam/ electric tracing).
• Low Temp spec services are limited to pressurized gases in utility distributions that have been dried for operation at ambient temps (N2, Natural Gas, IA, etc), and to Classes 150/ 300.
• Natural Bitumen has both a sulphur and a naphthenic acid content, and is associated with saline water. 5 CR/ 9 CR materials are used at elevated temperatures prior to hydrotreating to resist sulphidation &/ or naphthenic acid attack.
• Most of the Upgrader’s ‘cracking’ operations are low pressure; so Class 150/ 300 predominate, except where 600# Steam is used for purging or atomization.
27
Highlights from Specifications
• Users are encouraged to select Triple Offset Butterfly valves for sizes > NPS 16, but this is changing very slowly. UE-1 used ~ 40 such valves, including one each at NPS 54 and NPS 72.
• 600# Steam is used for process purposes and for smaller turbine drivers, and is typically specified as Class 600 RF. [History showed many casting leakers – so our specs go to full RT today]
• RTJ flanges are introduced for elevated temperatures at > 750 oF , and at Class 900.
• 900# Steam is distributed in 1 ¼ CR piping for power generation and for steam turbine drivers > 15,000 HP.
• 1 ¼ CR piping is also used for hot process streams that contain Hydrogen.
• Flanges are minimized at > Class 900, with a shift to BW ends or “Grayloc” type closures, and with PSB designs.
28
Highlights from Specifications
• Valve use is minimized in Class 2500 services; with Globes being used for isolations, and tilting disk checks used to protect spec change locations.
• Welded Seats are a norm and Backseats must be fixed in all pressure classes!
• Most Valve Trim is either full or partial stellite reflecting the erosive solids that permeate Oil Sands fluids, with priority being stellite on the body seat.
• Ball Valves & Plug Valves are in limited use. Ball Valves frequently used in “hardened” versions in Fluidized Bed Hydrocracker for HP services with erosion challenges.
• Drains and small bore connections are typically Y type Globes at > Class 900.
• Bellows Sealed Stems are < 10 % of small forged valves.
[this reflects Syncrude’s diluent choice].
29
Reliability is Essential, Quality is ‘King’
• Oil Sands operations are expensive & challenging. Freezing in the dark is all too real a risk!
• Our ‘culture’ is one where Safety comes First as a Value, and Reliability comes first as a priority. Fixed costs, regardless of production rates, ensure that our business focus is high availability & maximized volumes. Growth comes from internally generated cash-flow. Profitability comes when production reaches and is sustained in the upper third of our nameplate capacity.
• Turnarounds are huge events when they involve a Fluid Coker @ 40 to 50 days, 2500 tradesmen, as high as 1 Million workhours. Unplanned T/As have a $$ tag > 50M.
• PMI must be demonstrated by all pressure envelope components for every item, if not spec’d as CS or 304 SS.
30
Reliability is Essential, Quality is ‘King’
• Syncrude experienced a significant number of functional valve failures and loss of containment events in the 1980’s. They taught us that compliance with Industry Standards could not be assumed; and that changes in the supply-chain for valve castings and assembly was an ongoing concern.
• Our need for continuity of operations often led to high challenge situations – such as building an ASME Section VIII compliant containment shell around a NPS 16 Class 600 gate valve in superheated steam service with 2 active leaks in its body; or performing Hot Tap & Bypass tasks onto or around valves with stem/ gate separations.
• An aggressive program for enhanced Quality Management was implemented which culminated in our L-37 Spec, adoption of high levels of NDE, a rigorous Qualification process, and a carefully screened AML.
31
Reliability is Essential, Quality is ‘King’
• We approve selected Manufacturing Facilities, not Brands.
Our approvals can be size, class, and metallurgy specific.
• Integrated casting & assembly plants are preferred; but
long term 3rd Party casting sources can be accepted.
• Quality Programs must be comprehensive, certified, and
fully implemented!!
• Production samples are randomly selected and are tested
by selected 3rd Party “Failures Labs” – first against the
requirements of the applicable Industry Standards, then by
lengthened pressure and helium leakage tests & full RT,
and by metallurgical sampling & mechanical testing.
• Valves must have Design Registration in Province of
Alberta per CSA Std. B51 (CRNs from the ABSA).
32
Erosive Slurries
• Syncrude has more than 125 miles of large diameter piping carrying erosive slurries. NPS 28 is the norm at Base Mine, while NPS 30/ 32 are the norm at Aurora. Long runs of “Water” transfer systems of NPS 30 to NPS 54 also operate aboveground all year.
• These warm water based slurries can carry rocks and other solids to 5” in size, and they run at 15 – 18 ft./sec. Erosion & erosion/ corrosion can leave some CS or Cast CWI components worn by > 0.50” in just 2000 operating hours.
• Isolated branches must stay dry for winter operability!
• Many of the valves that isolate sections of these piping systems sit remote from infrastructure and at ambient temperatures in the active mining or waste deposit areas. Local or portable hydraulic actuators are used to drive their gates through the slurries.
33
Knife Gates in Erosive Slurries • “Old” Knife Gates in early Winter
• Newer Generation – Summer
34
Knife Gates in Erosive Slurries • We have developed a corporate spec for Knife Gate Valves
that builds on the MSS- SP-135- 2010 Industry Standard.
• Bi-directional dead-end service capable; internally retained
but replaceable wear rings U/S & D/S (rotatable & useable
in multiple positions); heavy tungsten carbide overlays on
wear rings and gate.
• Resilient element used to prevent gate passing leakage.
• Designed to prevent gate blowout up to hydrotest
pressures; strong stem to gate attachments.
• Weather/ dust protection for gates/ stems.
• Optional bonnets designed for full MAWP w. stem seals.
• Pressure tested between blind flanges without hydraulic
compression. Actuators good for -40 to 250 oF.
• CRN registered for -20 to 400 oF & full Class 150/ 300.
35
Current Challenges ……
• Increasing salinity, sodium & calcium in process waters that are typically recycled 15 – 20 times
• Escalation in piping sizes > NPS 30
• Chloride carry-over in Bitumen; and corrosion damage within Hydrotreaters & support units (ammonium bisulphide, chlorides at 10 – 20 k ppm, ammonium chloride & ammonium sulphate)
• Reduced tolerance for risks w.r.t. leakage through single isolation valves (Alberta’s OH&S requiring P.Eng. certified alternatives to DB&B or Block & Blind). Lack of substantive progress in API Standards!
• Cost effective options for shifts from CS to Duplex SS to High Alloy (C-276 and Alloy 825). Weld overlays vs. solid castings; alternate “coating” technologies.
• Retrofits for DB&B – single valve body options to minimize piping rework.
• Reduced tolerance for V.O.C. leakage
36
Additional Facts about the Oil Sands, and our
environmentally responsible production.
• Syncrude information, including environmental & social impacts and restoration activities: www.syncrude.ca
• Oil Sands Industry Information from Canadian Association of Petroleum Producers: www.capp.ca & www.canadasoilsands.ca & [email protected]
• Alberta Environment: www.environment.alberta.ca
• Oil Sands Developers Group (OSDG): www.oilsandsdevelopers.ca
• Alberta Biodiversity Monitoring Institute: www.abmi.ca
• Royal Society of Canada: www.rsc.ca