BP North Sea EOR lessons learned. Euan Duncan North Sea Discipline Lead Reservoir Engineer



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Transcription:

BP North Sea EOR lessons learned Euan Duncan North Sea Discipline Lead Reservoir Engineer

Enhanced Oil Recovery BP North Sea lessons learned 1. Current Context 2. History A few pictures Enablers & Lessons 3. Current projects 4. Future 1. Technology 2. Unlocking options

Enhanced Oil Recovery BP North Sea lessons learned so. Good planning & Collaboration are potential EOR enablers 1. North Sea context 2. History A few pictures Enablers & Lessons 3. Current projects 4. Future 1. Technology 2. Unlocking options Themes here are: EOR works in the subsurface & tends to grow with time Size of prize, access to infrastructure & injectant supply are critical Confidence in process is critical

Context North Sea Reserves & Resources (billion boe) 3 to 9 Yet to Find New Discoveries in 2012 0.05 Exploration Efficiency 4 to 10 New Fields on-stream in 2012 Possible & Probable 0.15 Recovery Efficiency 7 Produced in 2012 Proved & Sanctioned Developments 41 Produced to date 0.5 Production Efficiency Source: Oil & Gas UK Economic Report 2013

Delivering EOR Recovery Efficiency can be increased by making improvements across four levers: Recovery = Pore scale Factor displacement x Sweep x Drainage x Cut - offs Subsurface Delivery of EOR LoSal EOR Polymer Miscible Gas / CO 2 Bright Water Practical EOR Delivery New wells Logistics & Longer field life Effective patterns Plant & well efficiency LoSal is a registered trademark of BP plc BrightWater is a registered trademark of Nalco Company

Delivering EOR Recovery Efficiency can be increased by making improvements across four levers: Recovery = Pore scale Factor displacement x Sweep x Drainage x Cut - offs Subsurface Delivery of EOR LoSal EOR Polymer Miscible Gas / CO 2 Bright Water Practical EOR Delivery New wells Logistics & Longer field life Effective patterns Plant & well efficiency CONFIDENCE / STRATEGY ALIGNMENT LoSal is a registered trademark of BP plc BrightWater is a registered trademark of Nalco Company

North Sea EOR Project History Euan Duncan North Sea Discipline Lead Reservoir Engineer

BP EOR Focus Areas in North Sea Field locations with current & future projects Magnus Miller Ula LoSal is a trademark of BP plc

Miller Associated Gas Re-injection 1998 2000 Miller AGR New WAG compressor installed 3 wells converted to a limited WAG scheme 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

Miller Associated Gas Injection 1998 2000 2002 2004 Miller AGR Critical Enablers BP Alaska WAG experience Good reservoir sweep & high Sorw Lessons Learned: Compression performance WAG subsurface success Modelling workflow Too late 2006 2008 2010 2012 2014 2016 2018 2020

Miller Associated Gas Injection 1998 2000 2002 2004 2006 Miller AGR Critical Enablers BP Alaska WAG experience Good reservoir sweep & high Sorw Lessons Learned: Compression performance WAG subsurface success Modelling workflow Too late INJECTION 2008 2010 2012 2014 PRODUCTION 2016 2018 2020

Miller CO 2 project 1998 Miller AGR 2000 2002 Ula WAG Magnus WAG 2004 2006 2008 2010 2012 Miller WAG/CO2 2014 2016 2018 2020

Miller CO 2 Injection 1998 2000 2002 2004 2006 Miller AGR Ula WAG Magnus WAG Critical Enablers Infrastructure & Injectant supply Lessons Learned: EOR cannot pay for full platform costs Step too far for new technologies No fiscal regime at the time for CO 2, too late in field life, low oil price 2008 2010 Miller WAG/CO2 2012 2014 2016 2018 2020

Ula behind flood front pilot 1998 2000 2002 Miller AGR Ula WAG New WAG compressor installed 2 WAG injectors in 1999 to 4 in 2005 Increased gas capacity & further WAG wells in 2009 2004 2006 2008 2010 2012 2014 2016 2018 2020

Surveillance Data behind flood front pilot 1998 Miller AGR 2000 Ula WAG 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

Surveillance Data behind flood front pilot 1998 Miller AGR 2000 Ula WAG 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020

Ula future 1998 Miller AGR 2000 Ula WAG 2002 2004 2006 2008 2010 2012 2014 Blane gas & more wells Oselvar gas & more wells 2016 2018 2020 Expanded WAG

Ula WAG Scheme 1998 2000 2002 2004 Miller AGR Ula WAG Critical Enablers Injectant supply: Gas export lost when Cod field abandoned Miller compression experience Alaska experience Lessons Learned: Gas injector integrity Timing WAG bank is difficult Needed surveillance to understand 2006 2008 2010 2012 2014 Blane gas & more wells Oselvar gas & more wells 2016 2018 2020 Expanded WAG

Magnus WAG Scheme 1998 2000 Miller AGR Ula WAG New WAG compressor installed Gas import from stranded West of Shetland gas 2002 2004 2006 Magnus WAG Magnus Platform -New pipeline riser -Gas injection compressor -LPG recovery -66 well conversions 2008 2010 Sullom Voe Terminal -Fuel gas to power -Rich gas treatment & compression -Fiscal metering 2012 2014 West of Shetland -Subsea tie-ins ins -Pipeline end manifold (PLEM) Shetland Islands 2016 2018 2020

WAG WF Magnus Understanding the WAG target 50 m CPI Log GR TVDSS ILD 0 200 MD 0.2 200 2850 RHOB NPHI Principal Zonation Typical Biostrat Control Sequence Equivalents Regional TEMFS 50m 2900 2950 3000 MSM G MSM F MSM E MSM C / MSBRZ B Shale MSM A LK90 Upper MSM Lower MSM J60 J64 J63 hudlestoni eudoxus M60(A6) MSM drilled in 2010 M58z(E3) MSM drilled in 2009 3050 LK80 LKCF J62 3100 LK60 LK40 J50 J56 baylei base not shown here LK20, LK10 J54/52 rozencrantzi 20

WAG Benchmarking with Industry Data Magnus panels & Ula overall performance is better than most of the industry benchmarks

Magnus WAG 1998 2000 2002 2004 Miller AGR Ula WAG Magnus WAG Critical Enablers BP Alaska WAG experience Ula & Miller compression WoS Stranded gas Lessons Learned: Technical Experience Injectant supply critical System complexity and uptime in mature assets challenging Fiscal relief beneficial 2006 2008 Additional EOR patterns 2010 2012 2014 2016 2018 2020 Optimisation Flotel programme to extend CoP Additional EOR patterns

Magnus WAG 1998 2000 2002 2004 Miller AGR Ula WAG Magnus WAG Critical Enablers BP Alaska WAG experience Ula & Miller compression WoS Stranded gas Lessons Learned: Technical Experience Injectant supply critical System complexity and uptime in mature assets challenging Fiscal relief beneficial 2006 2008 2010 Additional EOR patterns Central Panel MSM-G 2012 2014 Optimisation 2016 2018 2020 Flotel programme to extend CoP Additional EOR patterns 500 m

Lessons learned from four EOR projects Recovery = Pore scale Factor Sweep Drainage Cut - offs displacement x x x Subsurface Delivery of EOR Subsurface Workflow knowledge Surveillance: Seismic, Sorm & Sorw etc CONFIDENCE

Lessons learned from four EOR projects Recovery = Pore scale Factor Sweep Drainage Cut - offs displacement x x x CONFIDENCE Subsurface Delivery of EOR Subsurface Workflow knowledge Surveillance: Seismic, Sorm & Sorw etc Well integrity Practical EOR Delivery - Injectant supply - Understanding changes to plant process critical - Fiscal Relief - Multiple phases of EOR

Future Projects Euan Duncan North Sea Discipline Lead Reservoir Engineer

Clair Ridge LoSal EOR 1998 2000 2002 Miller AGR Ula WAG Magnus WAG Critical Enablers BP Alaska LoSal EOR experience Big STOIIP Other benefits (scale & H2S) Lessons Learned: Align partnership Need big development for standalone LoSal EOR collaboration? 2004 2006 Miller WAG/CO2 2008 2010 2012 2014 2016 Clair Ridge Losal 2018 2020 Further phase of Clair

Schiehallion Polymer 3,000 ppm reservoir well 1998 2000 Miller AGR Ula WAG 2,000 ppm 1,000 ppm In facilities, mixed at 1,000 ppm Polymer degradation at very high shear rates (e.g., chokes) 850 ppm 2002 2004 Magnus WAG 6 500 ppm In bulk of reservoir, polymer acts as 850 ppm At sandface and fracture 5 1 At injection well perforations 4 2 3 2006 Miller WAG/CO2 <10 s -1 10 3 s -1 Effect of polymer concentration on shear viscosity (3630S in 1% NaCl at 25 o C). 10 5 s -1 2008 2010 2012 2014 2016 Clair Ridge Losal 2018 Schiehallion Polymer 2020

Schiehallion Polymer 3,000 ppm reservoir well 1998 2000 Miller AGR Ula WAG 2,000 ppm 1,000 ppm In facilities, mixed at 1,000 ppm Polymer degradation at very high shear rates (e.g., chokes) 850 ppm 2002 2004 Magnus WAG 6 500 ppm In bulk of reservoir, polymer acts as 850 ppm At sandface and fracture 5 1 At injection well perforations 4 2 3 2006 Miller WAG/CO2 <10 s -1 10 3 s -1 Effect of polymer concentration on shear viscosity (3630S in 1% NaCl at 25 o C). 10 5 s -1 2008 2010 2012 2014 2016 Clair Ridge Losal 2018 Schiehallion Polymer 2020

Schiehallion polymer lessons 1998 2000 2002 2004 2006 Miller AGR Ula WAG Magnus WAG Miller WAG/CO2 Critical Enablers Understand reservoir Large STOIIP collaboration? Partnership Knowledge Lessons Learned: Polymer delivery challenge: manufacture, logistics, mixing, degradation needs careful planning Significant upsides exists vs current technology 2008 2010 2012 2014 2016 2018 Clair Ridge Losal Schiehallion Polymer 2020 Future hopper

So, what are we doing now? Euan Duncan North Sea Discipline Lead Reservoir Engineer

Brackish water or losal

Technology 1. Developing new Water based IOR technologies: Pore scale Losal EOR plant 2. Facilities: Integrity management, Field life extension, PoB efficiency Plant & well uptime 3. Wells Cost Surveillance & conformance control

Screening process leading to Project Entry INPUTS Basic field data Cross Discipline engagement on enablers / barriers Mechanistic models Data Acquisition QA/QC Cross discipline engagement Full Field Studies GPO/ Project entry discussions RE Toolkit Screening Tool Short List Field scoping studies Project Studies across disciplines Full project planning Hopper Prioritised Hopper EOR/IOR Selection Matrix (multidiscipline) Agreed Work programme proposal Project entry OUTPUTS

High level screening Field 1 Field 2 Field 3 Field 4 Field 5 Field 6 Field 7 Field 8 Field 9 Field 10 Field 11 Field 12 Field 13 Field 14 Field 15 N2/Flue R R R Y Y Y R R R R R R Y R R H/C Miscible R G R G G G G Y R R R R G G R CO2 Miscible R G R G G G G Y R R Y Y G G R Immiscible G G G G G G G G G G G G G G G Waterflood G G G R G Y G G Y Y G G G G G LoSal G G Y R G R Y G Y Y G G G G G Brightwater G G R R G R R G Y Y G G G G G Alkaline (Caustic) Y R R R R R R R G G G G Y R Y Surfactant Y R R R R R R R Y G G G G R Y Polymer R R R R R R R R Y G G G Y R R Alkaline-Surfactant Y R R R R R R R Y G G G Y R Y Alkaline-Polymer R R R R R R R R Y G G G Y R R Polymer-Surfactant R R R R R R R R Y G G G Y R R A-S-Polymer R R R R R R R R Y G G G R R R Viscous: CHOPS Y R R R R R R R Y Y Y Y R R Y Viscous: Air (Combustion) G R Y R Y R R Y R G G G Y Y G Viscous: Steam Y R R R R R R R R Y R R R R R Brine data N N N N N Y Y Y Y Y Y Y Y N N Mid case barrels by field by option type Field 1 Field 2 Field 3 Field 4 Field 5 Field 6 Field 7 Field 8 Field 9 Field 10 Field 11 Field 12 Field 13 Field 14 Field 15 N2/Flue H/C Miscible CO2 Miscible Immiscible Waterflood LoSal Brightwater Alkaline (Caustic) Surfactant Polymer Alkaline-Surfactant Alkaline-Polymer Polymer-Surfactant A-S-Polymer Viscous: CHOPS Viscous: Air (Combustion) Viscous: Steam

Standardise Modelling Workflow 1. Fine Scale Mechanistic model with rock curves 2. Fine Scale Geological element model with rock curves 3. Fine Scale Depositional system Geological model with upscaled to pseudos Upscale rel perms if neccessary Upscale rel perms if neccessary 4. Full field model with areal pseudos & potentially EOR process pseudos

Screening Process: Summary of EOR project status Communication tools to understand status Field EOR Screening SCAL Production Forecast Injectanat Supply Facilities Design Project Economics Chance of Success Comments Field 1 EOR Optimsation Field 2 Polymer Field 2 Optimisation Field 3 Polymer Field 4 EOR? Field 5 Losal Field 6 Hisal? Field 7 EOR optimisation Field 8 Hisal? Field 5 upsides? Green Complete Complete Complete Complete Good NPV >50% Yellow In Progress In Progress In Progress In Progress Marginal 10-50% Red Not Started Not Started Not Started Not Started Negative NPV <10%

Building Confidence : Pyramid of proof Project Subsurface Technical Losal EOR example Corporate confidence Deploy Economics Pilot (Inter-Well Trials) Injectant supply & Facilities Knowledge Detailed Study (>15 Single Well Chemical Tracer Tests) Subsurface Data & Knowledge Screening Studies (>50 Corefloods). PLANNING INTEGRATION

EOR challenges & possible solutions Key Success Factors Low Cost Injectant Challenges Source Cost of supply or purchase Solutions Engage with CCSA to develop CO 2 EOR / CCS strategy. Collaboration supply chain shared facilities (eg ITF call) Subsurface Understanding Awareness of EOR. Understanding mechanisms Confidence DECC PILOT (screening, workshops, coreflood planning) Pyramid of Proof. Facilities Lack of space / weight ITF: Low Salinity facilities for brownfields. Include capacity for EOR within BoD s for new developments (FDP consent). Economics High front-end & increased OPEX costs.. Time to CoP. Pace!! Clusters formed for knowledge/cost sharing EOR hopper awareness. Potential for fiscal relief.

Lessons learned from four EOR projects Recovery = Pore scale Factor Sweep Drainage Cut - offs displacement x x x CONFIDENCE Subsurface Delivery of EOR Subsurface Workflow knowledge Surveillance: Seismic, Sorm & Sorw etc Well integrity Practical EOR Delivery - Injectant supply - Understanding changes to plant process critical - Fiscal Relief - Multiple phases of EOR

Lessons learned from BP EOR projects Recovery = Pore scale Factor Sweep Drainage Cut - offs displacement x x x Align with strategy, Development Planning & Scale (reservoir & infrastructure) Subsurface Delivery of EOR Subsurface Workflow knowledge Surveillance: Seismic, Sorm & Sorw etc Well integrity Practical EOR Delivery - Injectant supply - Understanding changes to plant process critical - Fiscal Relief - Multiple phases of EOR

BP EOR Focus Areas in North Sea Field locations with current & future projects Clair Ridge LoSal EOR Approved for s/u 2016 Greater Clair Future EOR & new technologies Schiehallion & Loyal Polymer vessel space Potential future optimisation Skarv Crestal gas Injection Started-up 2013 Magnus WAG since 2002 Optimisation ETAP Potential for water IOR Foinaven Potential for polymer + other? Ula WAG since 1999 Large upside potential Valhall Sulphate injection research LoSal is a registered trademark of BP plc

End

Magnus Hub Oil Production Rate (mstbd) Summary: Magnus Development phases Magnus Field Recoverable oil (mmstb) 160 140 120 100 Evolution of Magnus Field Production Profiles 1100 1000 900 Current Recovery of 820mmstb 800 700 600 2011 Depletion Plan 2010 Proved 2005 2000 1995 1994 1991 1987 1986 1982 - Initial Sanction Actual 80 60 500 1982 - Initial Sanction 1986 1987 1991 1994 1995 2000 2005 2010 Proved 2011 Depletion Plan (Historical profiles - Annex B revisions) 40 20 0 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025 2027 2029 2031 2033 2035 LKCF development Infill drilling to utilise 20 slots South Magnus subsea tie-back Phase I and Phase II infill drilling programmes Options for further WAG patterns and Extended EOR scheme to progress remaining CR volumes Increase off-take to 140mbd Revised petrophysical interpretation Miscible WAG EOR scheme for MSM and LKCF brownfield mods 8 new platform slots Magnus Full Field Recovery Factor 7 subsea & 15 platform wells MSM only WF development plant PW de-bottlenecking 20 additional wells Subsea injectors (SWIFT) North West Magnus satellite development from platform 30% 40% 50% 60% 70% PRODUCED PD - Base PUD1 - Infill Ph2 CR1 - Infill Ph3 & E-EOR CR4.1 - E-EOR & Blowdown Left in ground

Oil Rate [stb/d], green Ula WAG Increment Oil Rate [stb/d], green GOR [scf/bbl], red GOR [scf/bbl], red 10000 9000 8000 7000 6000 A12A oil rate and GOR from well tests WAG effect from A07C DHSV repair 10000 9000 8000 7000 6000 5000 4000 3000 2000 1000 Oil rate GOR TTAC 5000 4000 3000 2000 1000 0 0 Jan-99 Jan-01 Jan-03 Jan-05 Jan-07 Jan-09 Jan-11 18000 16000 14000 12000 10000 8000 6000 A15 oil rate and GOR from well tests WAG effect from A03A Recompletion WAG effect from A13A DHSV failure Oil rate GOR 8000 7000 6000 5000 4000 3000 4000 2000 2000 1000 0 Jan-96 Jan-98 Jan-00 Jan-02 Jan-04 Jan-06 Jan-08 Jan-10 0

Schiehallion Q204 Polymer Impact on Swivel Design Area for EOR equipment Separation flow loop Opus Plus Polymer viscosity optimised for max injectivity Production WI Polymer delivered as bulk chemical Impact on Separation and Produced water treatment e.g. Hydrocyclones Shear in chokes