New Tailings R_Lahaie.pdf

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OSTRF ConferenceDecember 7-10, 2008

1( New Tailings Concepts

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International Oil Sands Tailings ConferenceEdmonton, Alberta December 9, 2008

Syncrude Canada Ltd. New Tailings Concepts


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Acknowledgements

Syncrude has been working closely with internal experts,other Oil Sand developers, and with a number of third parties,notably:

Randy Mikula - CanmetENERGY

David Carrier - Argila Enterprises Ed McRoberts - AMEC

Gord McKenna - BGC Engineering

Glen Welch Pocock Industrial

Along with;University of Alberta, University of Saskatchewan, OKaneConsultants, Barr Engineering.


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Introduction

Update on two of the several tailings technologies

Syncrude is actively progressing through lab andfield trials:

MFT Centrifuge

MFT Accelerated Dewatering


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Syncrude Tailings R&D is focused on anumber of parallel fronts.

progressing tailings technologies aimed at meeting ourReclamation and Closure plans

Two technologies Syncrude is actively investigating are;

1) MFT Centrifuge and,2) MFT Accelerated Dewatering

these MFT dewatering technologies, are primarily targeting

possible implementation at Syncrudes Mildred Lake operationbut we see the potential application at other Syncrude leases.


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MFT Centrifuge Process overview

Syncrudes vision for MFT Centrifuge - a two step process;

Step 1: MFT dewatering utilizing horizontal solid bowl scroll

centrifuge technology with flocculent addition forming 2 streams:

MFTNominal >30wt% solids Centrate to

Settling BasinNominal 1.0 %wt solids

Cake - Soft Soil

Nominal 60wt% solids

Flocculent

Dilution

Centrate:

Relatively solids free water

having 0.5% to 1.0% wt solids

returned to the tailings water

system for recycle.

Cake:

60%wt solids - soft soil material

capturing greater than 95% of

the solids. Cake is almost the

original volume.


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MFT Centrifuge Process overview

Step 2: Subsequent dewatering of the cake by natural

processes; consolidation, desiccation and freeze thaw via

either/ or: 1 to 2 metre annual layers or lifts, delivering a trafficable

surface that can be reclaimed terrestrially;

A very thick, potentially 30 metre layer deposited in the minedout pits where, with time, consolidation further dewaters the

cake to deliver a deposit that can be reclaimed terrestrially or

by water capping.


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MFT Centrifuge Completed Testing

2005 MFT Centrifuge bench trials Continuous feed bench scale centrifuge test at @ CanmetENERGY

2007 MFT Centrifuge Field test

Initial feasibility studies via a 2 week test using relatively largeoilfield centrifuges

2008 MFT Centrifuge Field test a 2 month test focusingon: MFT flocculation and centrifuge process;

Preliminary cake transportation assessment - conveyors andpositive displacement pumps / pipeline;

Providing material to;

Determine deposit performance subjected to natural consolidation,desiccation and freeze thaw; and

Longer tem monitoring to assess environmental issues.


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Two pods of oilfield scale centrifuges were operated inparallel;

1. Two Alfa Laval Lynx 40s (nominal 400 mm dia.) runningin parallel and operated by BOS Solutions Inc.

Prime focus was to provide centrifuge cake for:

transportation assessment conveyor and positive displacement pump /

pipeline studies Bulk materials for geotechnical and environmental studies.

2. Single MiSWACO 518 centrifuge ( nominal 355 mm dia.) Advance MFT flocculation and MFT centrifuge process

understanding: Flocculent optimization studies

Centrifuge operational parameter assessments.

2008 MFT Centrifuge Field Test - Scope


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2008 MFT Centrifuge Test site

2008 MFT Centrifuge Field Test

Plant Arrangement

Test Plant

Interim MFT

supply pondMFT & process

water tanks

Centrifuge cake

deposits


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Video of BOS Solutions Centrifuge operation, conveyor and deposit formationVideo of BOS Solutions Centrifuge operation, conveyor and deposit formation


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2008 MFT Centrifuge Positive Displacement Pump

Testing


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Note: immediate additional water release(no rain experienced prior to photograph)


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Compile 2008 centrifuge process data with the report earlyin 2009 Preliminary results show promise

Technology is robust

Flocculent consumption reducing with machine performance

Machine solids throughput on target / high solids capture in cake

Centrifuge cake transportation and deposits

Preliminary results are encouraging and equipment scoping studiesare planned for 2009

Geotechnical monitoring will continue into late 2009.

Multi year environmental assessments are underway with

internal experts, academic partners and consultants. Centrifuge scale up studies possible 2009 testing.

Scale up required from the nominal 400 mm to 1000 mm diametermachines.

MFT Centrifuge looking ahead


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MFT Accelerated Dewatering Process overview

Utilized in Florida phosphate industry:

30m+ deep impoundment constructed in the mined out pit and filled with MFT;

Water removal is enabled and actively managed via decant structure and rim ditching;

Results in a reduction of MFT volume by up to 50% after some 3 to 5 years; Delivers a soft soil material, that when suitably capped, can be reclaimed terrestrially;

Offers promise for implementation in Syncrudes mined out pits.


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Process testing at CanmetEnergy:

Small scale drying experiments to assess impacts of chemical amendment optimization; and

Large lab test (bins) carried out to provide data to allow full scale projections.

Significant improvement in MFT volume reduction was observed

2 to 5 times increase in net consolidation

Process likely scale sensitive

MFT Accelerated Dewatering

Completed Lab Testing


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Construction planned: 80m x 80m x 10m deep MFT test pond constructed

and filled in 2009 and operated for several years;

Objective: to provide planning and geotechnical parameters and to act as a

platform on which environmental assessments can be carried out over the

complete development cycle pond filling through to reclamation.

2009 MFT Accelerated Dewatering

Field Test - Scope


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Summary quotes from Al Fairs Summary

No silver bullet it will take more than one technology to deal with oil sands tailings

Syncrude is progressing MFT Centrifuge, MFT Accelerated Dewatering along with

CT and other technologies.

Different MFT management technologies will need to be used at different sites, dependent of

site specifics (i.e. existing MFT inventories, presence of an upgrader, (heat integration) nature

of ore body, lease geography etc.).

Mildred Lake operations has a relatively large legacy MFT volume, therefore it is the

prime candidate for possible implementation of these technologies.

It will take time to develop and commercially implement the various MFT management

technologies.

Development plans for these technologies will take several years as the operational

and environmental details need to be well understood before implementation.

Syncrude is committed to successfully managing its tailings in a manner that meets the needs of

the environment and our stakeholders.

These R&D activities are major undertakings emphasizing Syncrudes commitment

to meeting its Closure Plan obligation.

Documents

New Tailings R_Lahaie.pdf