Monitoring storage efficiency during CO2 injection for enhanced oil recovery in depleted oilfields

Ashwin PasumartiSrikanta MishraAndrew BurchwellSanjay MawalkarNeeraj GuptaRick Pardini

1 11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA

Outline Review of Concepts: Storage in Deep Saline Aquifer vs EOR Depletion - Storage Capacity Relationship

Performance Metrics Storage Efficiency Factor Excess Storage Capacity

Dashboard Development

Key Takeaways

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA2

CO2 Storage in Deep Saline Aquifers

CO2 injection into an aquifer creates a plume.

Pressure profile generated.

All injected CO2 is stored either in supercritical state or by dissolution into the brine.

Bachu, S., 2015, Review of CO 2 storage efficiency in deep saline aquifers: International Journal of Greenhouse Gas Control, v. 40, p. 188-202.

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA3

CO2-EOR & Storage

CO2-EOR is a proven and an economically-viable enhanced oil recovery technique.

Incidental CO2 storage occurs with oil recovery.

Synergistic opportunity for CCUS.

Monitoring CO2-storage to quantify the relationship between storage capacity and voidage.

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA4

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA

Oil

Oil

Gas

Oil

GasOil

P = PiPi > Pb

P = PoPo << Pb Pi < P < Pb

Depletion CO2 Injection

Natural Gas CO2

Natural Gas CO2

From Depletion to Injection

5

Hydrocarbon Pore Volume (HCPV)

General Material Balance Equation

Gas

CO2

Oil

CO2-in-Gas-Phase Volume

Associated Gas Volume

Oil Volume

+

+

=

Production Void space for CO2

∗ , ,

, ∗ ∗ , ∗ ,

∗ ,

Pressure-dependent fluid properties

CO2Capacity

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA

∗ ,

+

6

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA

Study Area: Example Application

DOE initiative to advance field-scale deployment of CCUS in Northern Michigan

Ongoing CO2 injection of 1 million metric tons alongside EOR + monitoring

6 depleted oilfields under study

Partnership with Core Energy, LLC Injection-ready CO2 Surface infrastructure

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Quantifying Storage Efficiency

The quantity of CO2 injection required to store each unit of CO2

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA

Reciprocal of CO2-retention

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Illustration: Storage Efficiency Ratio

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA9

Quantifying Storage Capacity

Storage capacity estimate

CO2 stored in the reservoir

Oil Rate

This estimate represents the upper limit of CO2 -storage capacity, assuming the reservoir was re-pressurized to discovery pressure.

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA10

Illustration: Excess Storage Capacity

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA11

Other Performance Metrics

Summary of production data Historical flow rates Cumulative production data

EOR performance trends Incremental oil recovery efficiency CO2 storage efficiency Net CO2 utilization factor

Operationalperformance trends Voidage replacement ratio Producing CO2-Oil ratio

Storage performance trends Incremental oil recovery factor

vs CO2 storage CO2 storage capacity vs

voidage

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA12

Reef-scale Monitoring: Dover 33

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA

Oil Rate vs Time Cumulative Volumes vs Time Δ Recovery vs HCPV’s Injected

Voidage Ratio vs Time Δ Recovery vs Storage Net Utilization Factor vs HCPV’s Injected

Producing GOR vs Time

Storage vs Total Produced VolumeStorage Efficiency Factor vs HCPV’s Injected

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Comparative Performance Dashboard

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA14

Key Takeaways

Monitoring data (pressure and injection volumes) has been analyzed to make inferences about CO2 storage performance.

Material balance techniques may be applied to quantify the storage capacity of a reef.

The Storage Efficiency Ratio is an efficiency metric quantifying the amount of CO2 injection required to store each unit of CO2.

Excel-based dashboard tool enables rapid comparison and ranking of reef storage performance, using multiple metrics.

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA15

Acknowledgements

Funding for this study was provided by the Midwest Regional Carbon Sequestration Partnership (MRCSP). MRCSP is supported by U.S. Department

of Energy-National Energy Technology Laboratory Agreement No. DE-FC26-0NT42589 with co-funding provided by the Ohio Development Services Agency (for regional research in Ohio), Core Energy, LLC, and several other partners.

16 11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA

800.201.2011 | solutions@battelle.org | www.battelle.org

Input RequirementsField-level historical oil and gas produced volumes

Field-level current oil, gas and CO2 injection/production volumes

Original oil in place, OOIP, STB

Original reservoir pressure, or discovery pressure, Pr – psi

Fluid properties calculated at discovery pressure:CO2 Formation Volume Factor , Bg,CO2 - rcf/scfGas Formation Volume Factor, Bg - rcf/scfOil Formation Volume Factor, Bo - RB/STBSolution Gas-Oil Ratio, Rs - Mscf/STBCO2-Oil Solution Gas-Oil Ratio, Rs, CO2 - Mscf/STB

Remove??

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA

Dover 33: Storage Capacity Confirmation that CO2 -

EOR has reached point of diminishing returns.

Expanding gas-cap Reservoir begins to re-pressurize toward discovery pressure

~370,000 MT of CO2storage capacity has been created.

11th Monitoring Network Meeting ● June 13th - 15th, 2017Traverse City, Michigan, USA

EOR Performance Trends

Incremental oil recovery obtained per normalized unit of CO2injected.

EOR Performance Trends

The net utilization factor represents the cumulative volume of CO2stored (lost) in the reservoir for each barrel of oil produced.