Water Use and Aquatic Reclamation at Syncrude Canada Ltd. Integrated Oil Sands Mining Operation

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


Presentation Outline

• Water Use– Background– Bitumen Production Process– Water Use– Water Quality– Summary

• Base Mine Lake (BML) Reclamation– Background– Research Summary– Path Forward


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%


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.


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


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.%)


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;


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.


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)


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


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;


• 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?


OSPW Historical Chloride Concentrations

1000

0

200

400

600

800

1979 1989 1999 2009

Con

cen

trat

ion

(m

g/L

)


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)


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.


Base Mine Lake circa 2012

Base Mine Lake (BML) Reclamation


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.


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


Reclamation Options

Oil Sands Process Material

Dry Landscapes• Vegetation• Forest

Wet Landscapes• Lakes• Wetlands


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


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


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.


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.


Field Experimental Test Ponds (1989 - Present)

Water Cap - 1989

MFT Placement - 19891989

2001

1993


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%


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


• 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


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


Cross section of BML at Start (T0)

250m

308.7m

303.7m

294m


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

)


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


Fish Studies-Survival-Health

Benthic Invertebrate

Vegetation-Riparian-Littoral

Plankton Surveys-Abundance-diversity


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


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”.


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.


Thank You

Water Use and Aquatic Reclamation at Syncrude Canada Ltd. Integrated Oil Sands Mining Operation

Documents

Transcript of Water Use and Aquatic Reclamation at Syncrude Canada Ltd. Integrated Oil Sands Mining Operation