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APPEGGA Meeting - September 21,2010 1
Warren Zubot, M.Sc., P.Eng.
APEGGA LuncheonSept. 21, 2010
Water Use and Aquatic Reclamation atSyncrude Canada Ltd.
Integrated Oil Sands Mining Operation
APPEGGA Meeting - September 21,2010 2
Presentation Outline
• Water Use– Background– Bitumen Production Process– Water Use– Water Quality– Summary
• Base Mine Lake (BML) Reclamation– Background– Research Summary– Path Forward
APPEGGA Meeting - September 21,2010 3
Syncrude Canada Ltd - Background
Peace RiverPeace River
Athabasca Athabasca
Cold LakeCold Lake
• Operates an integrated open-pit oil sands mining, extraction and upgrading operation in the Athabasca Region of Northeastern Alberta, Canada.
• Syncrude is a joint venture company incorporated in 1964;
Sinopec Oil Sands
Partnership9.03%
Imperial OilResources
25%
Mocal EnergyLimited
5%
Murphy OilCompany Ltd.
5%
Nexen Oil SandsPartnership
7.23%Suncor Oil Sands
Partnership12%
Canadian Oil Sands
Limited36.74%
APPEGGA Meeting - September 21,2010 4
Syncrude Canada Ltd – Background (Cont’d)
• Bitumen is derived from the oilsands deposits by open-pit mining and water based extraction techniques;
• Recovered bitumen is upgraded into marketable low-sulphur synthetic crude oil (SCO);
• In 1978, 3.6 million barrels of SCO produced;
• In 2008, 105.8 million barrels of SCO produced;
• Currently, production capacity is equivalent to about 15% of Canada’s domestic oil requirements;
• Based on current production rates, Syncrude’s bitumen reserves are sufficient to operate for an additional 70 to 115 years.
APPEGGA Meeting - September 21,2010 5
Crusher Cyclofeeder
Oil Sand SlurryHydrotransport
Froth to upgrading
middling layer
underflow
Upgrading + Utilities
AthabascaRiver
Raw Water Import
Tailings
Dyke
Tailings
DykeSand
Beach
Water
MFT
UpgradingEffluent
OSPW
Recycle Water Pond
Simplified Process Flow Diagram
APPEGGA Meeting - September 21,2010 6
Major water sourcesSCO Production is reliant on two major water sources.
1. Raw Water imported from the Athabasca River;
– Between 2003 and 2007, raw water import averaged ~ 34 Mm3/year;
– Used by the Upgrader/Utilities;
– Two largest users of raw water:
• Cooling Towers;
• Water Treatment Plant (boiler feed water).
Constitute ~ 75% ofraw water requirements
2. Oil Sands Process Water (Recycle water)
– Tailings systems recycle ~ 150 Mm3/year (80 000 USGPM) to satisfy bitumen extraction, process cooling, and hydrotransport requirements.
– Ground and Surface Water
• Other water inputs include:
– Formation (Connate Water) (Water content ~4 wt.%)
APPEGGA Meeting - September 21,2010 7
Raw (Athabasca River) Water
Athabasca River D/S Fort McMurray
0
200
400
600
800
1000
1200
1400
1600F
low
rate
(m3 /s
)
Mean Minimum
Based on AE Discharge Data: 1957-2004* RAMP
• Average annual river flow is ~ 600 m3/s;• Current annual flow diversion is equivalent to ~ 18 hours of average river flow;
APPEGGA Meeting - September 21,2010 8
Syncrude’s Raw Water Circuit
Utility Water
Fire Water
Seal Water
Tailings Makeup
Water Treatment Plant
Boilers
Steam System
Condensate Loss
Blowdown
Blowdown & Regenerant Waste
Cooling Towers
EvaporationBlowdown
Potable Water Plant
Potable Water Distribution System
Blowdown
Sanitary Sewage Treatment
Discharge
Raw Water
Vent & H2
Tailings
Athabasca R.
APPEGGA Meeting - September 21,2010 9
Oil Sands Process Water (OSPW)
++
NaOH(80-150 g/t
ore)
++
During processing:- Salts released (Na+, Cl-, SO4
=, Ca++, etc.);- Organic acids solubilized (i.e., Naphthenic
Acids);- Water softening reactions.
Tailings Slurry
Release Water
MFT SandSand
PLANT(Processing
cooling)
APPEGGA Meeting - September 21,2010 10
MLSB
Syphon
Str
eam
73
SEP Junior
Highw
ay
63
SEP TFT Return to WIP
SEP Barge
SWSS Decant Line to
WIP
79
0 5
B / Lin
e 10
System 3
4B / Line 9
791
Dredge
691
Cok
e L
ine
5A
Stream
73
Plant 6
69 0
Suncor
SuncorPond 5
Plt 6
SWSS
North Mine
Coke Line
Plt5
SuncorPond ?
Base Plant
Ruth Lake
Beaver Creek
Reservoir
Mildred Lake
SW Interceptor Ditch
Hig
hw
ay
63
MacKay River
W1 Dump W2
Dump
MFT Barge
RCW Barg
e
CT
Decant
SW Pit Disposal
Area WIP SEP
Tailings RCW System
System 4
System 1
System 5
System 6
System 2
NEP
AthabascaRiver
APPEGGA Meeting - September 21,2010 11
Water Management
– Optimize containment – minimize volume.
• Tools:– Conservation;– Treatment for reuse;– Treatment for release.
• Water quantity and quality dependent on tailings management practices:– MFT densification: Convert pore water to “free” water;– Total OSPW inventory is ~1.1 billion m3;– About 100 Mm3 available as “free” water for plant recycle.
• Goals for oil sands processing:– Plant operations require water of sufficient quantity and
quality;
APPEGGA Meeting - September 21,2010 12
• Salts are added from ore, process aids, and chemicals in engineered tailings;
• Salt concentrations increase through recycling.
• Net effect is that salinity increases within the RCW system;• Ion “build-up” is a water management focus.
Extraction
Tailings
• Salts from ore• NaOH • CaSO4
• Salts from boiler water treatment
• Cooling tower blowdown• Ammonia
What Impacts OSPW Quality in Operations?
APPEGGA Meeting - September 21,2010 13
OSPW Historical Chloride Concentrations
1000
0
200
400
600
800
1979 1989 1999 2009
Con
cen
trat
ion
(m
g/L
)
APPEGGA Meeting - September 21,2010 14
Oil Sands Process Water
Constituentsof Concern
SuspendedSolids
Free PhaseHydrocarbons
DissolvedOrganics
DissolvedSolids
Treatment of OSPW for return to environment
Treatment of OSPW for reuse (replace Athabasca River import)
Constituentsof Concern
SuspendedSolids
Free PhaseHydrocarbons
DissolvedOrganics
DissolvedSolids
Treatment of OSPW for return to environment
Treatment of OSPW for reuse (replace Athabasca River import)
APPEGGA Meeting - September 21,2010 15
Summary
• To produce ~15 % of Canada’s energy requirements, current diversions from the Athabasca River are less than a 1-day equivalent of average annual flow;
• Highly efficient water recycle practices result in increased concentrations of Total Dissolved Solids (salinity) in the oil sands process water (OSPW) reused on-site;
• OSPW quality is a function of the ore quality, processing conditions, recycle efficiency and tailings management practices;
• Caustic (NaOH) is both a process aid (surfactant liberation) and water softener;
• Syncrude’s operations could proceed into the 22nd century – requires sustainable water management practices.
APPEGGA Meeting - September 21,2010 16
Base Mine Lake circa 2012
Base Mine Lake (BML) Reclamation
APPEGGA Meeting - September 21,2010 17
Background
• The BML concept was the most significant corporate commitment made during the 1993 hearing on the Syncrude expansion;
• ERCB and AENV approvals require for the development of the BML to demonstrate the technology;
• The BML facility was also the subject of extensive consultation and a subsequent agreement between SCL and the Fort McKay First Nation;
• Following ERCB and AE approval for ’93 expansion, both regulators documented their expectation the facility be delivered as per SCL’s commitments.
• The BML will permit permanent storage and subsequent remediation of up to 207 Mm3 of FFT.
APPEGGA Meeting - September 21,2010 18
Reclamation Objectives
• Produce self-sustaining landscapes – terrestrial and aquatic;
• “Equivalent Capability” to pre-disturbed habitats;
• Meets the needs of future generations and balances environmental, social and economic issues.
Base Mine Lake
APPEGGA Meeting - September 21,2010 19
Reclamation Options
Oil Sands Process Material
Dry Landscapes• Vegetation• Forest
Wet Landscapes• Lakes• Wetlands
APPEGGA Meeting - September 21,2010 20
EPLs are a major feature in oil sands lease closure landscapes
Number of EPLs
>25
Mean Surface Area
~ 4km2
Mean Depth ~ 30m
Mean Fluid Volume
~ 100Mm3
Water/FFT Ratio
<0.1 to ~0.8 Base MineLake
APPEGGA Meeting - September 21,2010 21
End-Pit Lakes – the Concept
Fluid Fine Tails
Water Cap Water Output(discharge)
Water Input(recharge)
Littoral ZoneWater Zone
5m-Fish, Invertebrates, Plankton
Beach
Overburden, Rejects or Sand
Water
Fine Tails
Release
Lake 5m-
50m-
MicrobialActivity
Overburden, Rejects
Fluid Fine Tails (Densification)
Seepage
MixingWater Cap
APPEGGA Meeting - September 21,2010 22
What are the objectives in developing the BML?
Demonstrate that water-capped lakes:
Are an effective technology to manage volumes of fluid fine tails;
Will develop into self-sustaining lake ecosystems;
Will slowly trend towards similar ecosystems in the region;
Are efficient “bioreactors” to remediate constituents of concern present in OSPW.
APPEGGA Meeting - September 21,2010 23
To develop the water capping option, SCL Research has examined
1. Physical Processes• Fine Tails re-suspension;• Densification;• Stratification;• Hydrology.
2. Chemical Properties• Composition;• Sources, Mass flux;• Inorganic/organic constituents;• Degradation.
3. Toxicology• Acute/Chronic;• Identification of toxicants;• Bioaccumulation/food chain• Removal.
4. Biological Performance• Productivity, Diversity;• Ecosystem dynamics;• Food web;• Colonization and stability.
APPEGGA Meeting - September 21,2010 24
Field Experimental Test Ponds (1989 - Present)
Water Cap - 1989
MFT Placement - 19891989
2001
1993
APPEGGA Meeting - September 21,2010 25
Physical Processes – FFT Densification
• Research indicates FFT densification is occurring and has accelerated in recent years;
• Densification results in increased strength.
4 32.8 26.95 34.8 28.46 36.5 29.67 37.9 30.68 39.1 31.59 40.2 32.3
10 41.2 33.011 42.1 33.612 42.9 34.213 43.6 34.714 44.3 35.215 44.9 35.716 45.5 36.117 46.1 36.518 46.6 36.919 47.1 37.220 47.6 37.6
Densification: Fluid Fine Tails
0
5
10
15
20
25
30
35
40
45
50
0 5 10 15 20
Fin
es/(
Fin
es+
Wate
r)
(g/1
00g
)
Biologically Active
Biologically InactiveFFT at 45%
FFT at 30%
APPEGGA Meeting - September 21,2010 26
What was learned from research about water circulation?
• Layers of water at different temperatures naturally form in deeper lakes in the summer;
• With an initial depth of 5 m, we expect layers of water will develop in BML; these layers will mix in the spring/fall, similar to a natural lake;
• Maintain oxygen concentrations;
• Duplicating natural seasonal patterns of water flow-through and water level will assist the development of a self-sustaining lake.
26
APPEGGA Meeting - September 21,2010 27
• Will winds create mixing in the BML such that the fine materials in the FFT zone are re-suspended?
Physical Process – Stability of Water/FFT Interface
Flume Experiment
APPEGGA Meeting - September 21,2010 28
Physical Processes – Stability of Water/FFT Interface
0
2
4
6
8
10
12
0 5 10 15 20
Wind Velocity (m/s)
Wa
ter
Dep
th (
m) 2 km
4 km6 km8 km
AnnualStormEvent
10 year StormEvent
100 yearStormEvent
APPEGGA Meeting - September 21,2010 29
Cross section of BML at Start (T0)
250m
308.7m
303.7m
294m
APPEGGA Meeting - September 21,2010 30
Chemical Properties – Naphthenic Acids
Naphthenic Acid Degradation
0
10
20
30
40
50
60
70
80
90
100
0 1 2 3 4 5 6 7 8 9 10
Time(years)
Con
cent
rati
on (
ppm
)
APPEGGA Meeting - September 21,2010 31
0
20
40
60
80
100
MLSB (fresh) MLSB(aged 1 Year) MLSB (Aged 5Years)
% S
urv
ivia
l
0
20
40
60
80
100
120
Co
nce
ntr
atio
n (
mg
/L)
Trout (96 h) Daphnia (48 h) NA Concentration
Chemical Properties – Naphthenic Acids and Acute Toxicity
APPEGGA Meeting - September 21,2010 32
Fish Studies-Survival-Health
Benthic Invertebrate
Vegetation-Riparian-Littoral
Plankton Surveys-Abundance-diversity
APPEGGA Meeting - September 21,2010 33
APPEGGA Meeting - September 21,2010 34
What Have We Learned?
• The lake will stratify into a layer of fine tails (MFT) overlain by a cap of water;
• Acute toxicity of BML water will depend on dewatering rates and is anticipated to be removed within one to two years;
• Water inputs into the lake will be a combination of Athabasca River water, Beaver Creek reservoir water, watershed water, and FFT porewater.
Experimental Test Ponds After 10+ Years
APPEGGA Meeting - September 21,2010 35
What Have We Learned?
• Over time, the water quality will improve and will become more consistent with freshwater ecosystems in the region to support freshwater life.
• Concurrent with water quality improvements, littoral zones will develop;
• Ecosystem development in test ponds suggests water capped lakes can provide suitable habitat for native plants and animals.
Example of mats of bacteria, fungi and algae that developed in test ponds. This is where much of the break-down of organics will occur and facilitates the role as a “bioreactor”.
APPEGGA Meeting - September 21,2010 36
BML - Major Benefits
Fluid Storage- up to 207Mm3 of Fluid Fine Tails and up to 40Mm3 of water (fluid inventory management);
Demonstrate self-remediation/treatment of OSPW for ultimate return to the environment;
Value added feature in the lease closure landscape;
Viable BML will help mitigate public concerns relating to the industry’s ability to successfully reclaim mined out areas.
APPEGGA Meeting - September 21,2010 37
Thank You