DE-NT0006553

Goal
The goal of this project is to define, plan, conduct and evaluate the results of a field trial of a methane hydrate production methodology whereby carbon dioxide (CO2) molecules are exchanged in situ for methane (CH₄) molecules within a hydrate structure, releasing the methane for production. The objective is to evaluate the viability of this hydrate production technique and to understand the implications of the process at a field scale.

Conceptual rendering of proposed CO₂ ? CH₄ exchange methodology for the production of natural gas from hydrates.

Performer
ConocoPhillips Company, Houston TX and Anchorage AK
Japan Oil, Gas and Metals National Corporation (JOGMEC), Japan

Background
Globally and for the U.S., methane hydrates represent a potentially huge new source of the cleanest fossil fuel. A recent Minerals Management Service study estimated methane hydrate resources in the Gulf of Mexico at 21,000 trillion cubic feet (TCF), one hundred times the current U.S. proved reserves of natural gas. Hydrate accumulations off the Pacific and Atlantic coasts and on Alaska?s North Slope (ANS) hold additional potential. Yet this potential will remain untapped unless a technically and economically viable means of producing methane from hydrates is found.

Laboratory experiments conducted by ConocoPhillips and the University of Bergen have demonstrated the effectiveness of exchanging CO₂ for CH₄ in the hydrate structure, a process that releases the CH₄ molecules for production purposes. Key observations in those studies include the rapid rates of CO₂-CH₄ exchange in hydrates formed in porous media under a range of initial conditions; the efficiency of the carbon dioxide displacing the methane from the hydrate structure that approaches theoretical limits; and the preservation of measurable permeability in the porous media during hydrate formation and exchange. The most important observation is that the exchange process (as performed in the laboratory) does not involve the release of free water to the pore system. Instead, the process appears to dissociate and re-form hydrate at very fast rates and on a micro-scale in such a manner that there is no free water formed or significant heat-of-reaction issues.

Under this project, ConocoPhillips plans to perform the first field trial of this promising, methane hydrates production methodology at a site on the Alaska North Slope.

Potential Impacts
The project will add significant data and knowledge to the body of hydrates science. Geologic and geophysical science used to locate and quantify methane hydrate deposits will be expanded as field trial sites are identified and prioritized. Hydrate reservoir modeling capabilities will be advanced as the algorithms needed to simulate the exchange process are developed. Experience in drilling and completions technology related specifically to gas hydrates will also be gained.

A successful initial field trial will serve to inform planning of other longer-term tests needed to advance viable production technologies for methane hydrates. The exchange methodology could prove to be a critical tool for helping to unlock the methane hydrate resource in a manner that minimizes adverse environmental impacts while offering the potential to simultaneously sequester CO₂.

Accomplishments

• After measurement and compositional analysis, gas is flared at the Ignik Sikumi # 1 well site

  Successfully completed hydrate production testing operations at the Ignik Sikumi#1 well in the Prudhoe Bay unit on Alaska?s North Slope. Key production test achievements include:
  • Development and installation of equipment and infrastructure necessary to conduct the production test.
  • Injection of ~210,000 standard cubic feet (scf) of mixed carbon dioxide/nitrogen (CO₂/N₂) gas into the targeted hydrate-bearing portion of the well.
  • Sustainable flowback of gas from the well over an extended portion of the approximate 6 week production period.
  • Collection of a large suite of data from the well, including continuous temperature and pressure monitoring and real-time data on return gas compositions and constituent volumes.
  • Incident free operations throughout the field test.
  • Successful permanent plugging and abandonment of the well and reclamation of the ice pad-based well-site.
• Addition of JOGMEC as a partner supporting project production testing efforts.
• Completed laboratory experiments evaluating operational issues associated with the use of a CO₂/N₂ gas mixture as a hydrate reservoir injectant in place of liquid CO₂.
• Simulated the temperature behavior of the intended production test injection fluid, allowing determination of required surface heating capacity for field operations.
• Completed preliminary evaluation of data collected during 2011 drilling operations.
  • Logging results indicate four gas hydrate-bearing sand horizons in the well (in accordance with pre-drill predictions) including a 144 ft thick zone of clean, high-porosity sandstone with high gas hydrate saturation in the Sagavanirktok ?Upper C?, which represents optimal pressure-temperature conditions for conducting the planned field trial.
  • Schlumberger?s Express Pressure Tool (XPT) tool successfully acquired data that will yield insight into ambient reservoir pressure and potential injectivity of various stratigraphic units.
  • Schlumberger?s Modular Formation Dynamic Tester (MDT) tool was used primarily to conduct tests designed to measure formation breakdown pressures.
• Successful drilling, logging, instrumentation, completion and temporary suspension of the Ignik Sikumi #1 gas hydrate field trial well from an ice pad in the Prudhoe Bay operating Unit (PBU) on the North Slope of Alaska.
  • Operations included a comprehensive downhole data acquisition and site characterization program and installation of a fully-instrumented wellbore completion [PDF-schematic courtesy ConocoPhillips] available for additional field production testing.
  • Operations were completed without health, safety or environmental incident
  • Operations were conducted from a 500ft x 500 ft ice pad adjacent to the PBU L-Pad access road.
  • The surface hole was drilled, using water-based mud and logging-while-drilling (LWD) measurement, to a depth of 1,482 ft and then cased, cemented and pressure tested.
  • The remainder of the well was drilled (with LWD) to total depth of 2,597 ft using oil-based mud.
  • Wireline logs were obtained including: gamma-ray, resistivity, high resolution density, neutron porosity, oil-based mud imaging, combinable magnetic resonance, sonic scanner and borehole resistivity scanner.
  • Short duration tests were conducted using Schlumberger?s Express Pressure Tool (XPT) and Modular Formation Dynamic Tester (MDT).
  • Lower well completion included installation of an instrumented casing string with downhole temperature and pressure gauges and a continuous, fiber optic distributed temperature sensor.
  • Upper well completion included installation chemical injection and gas lift mandrels.
  • Freeze protection was implemented and the well temporarily suspended in preparation for anticipated re-entry during a subsequent winter drilling season.
• Acquired PBU Working Interest Owner approval for the performance of a two winter season field test, as a tract operation, from an ice pad near the PBU L-Pad
• Completed modeling efforts to determine potential effects on the field test targeted hydrate zone from ongoing conventional oil and gas operations near the PBU L-Pad.
• Completed petrophysical studies providing supporting data for the planning of project field testing
• Completed reservoir simulation for the production test, providing critical test design information
• Completed laboratory experiments evaluating the effect of CO₂ hydrate formation on sample permeability
• Completed detailed evaluation, ranking and recommendation of project field sites on ANS

Current Status (May 2012)
The Ignik Sikumi gas hydrate field trial has been completed. Review the archive of reports that were posted as the well operations took place.

Production test operations at the Ignik Sikumi gas hydrate well were completed on May 6, 2012 with reclamation of the ice pad-based site. The focus has now shifted to evaluating the extensive volume of test data. Initial data quality checks and corrections will be followed by a careful and deliberate set of analyses to be performed through project completion in June 2013. The analysis and interpretation of the data will be critical to understanding the test results and their implications.

Ignik Sikumi #1 field trial well site

Nordic-Calista Drilling Rig #3 on site at the Ignik Sikumi #1 well, Prudhoe Bay Unit, Alaska North Slope - photo courtesy ConocoPhillips

Project Start: October 1, 2008
Project End: June 30, 2013

Project Cost Information:
Site Selection (Phase 1) ? DOE Contribution: $0, Cost Share Contribution: $288,378
Field Test Planning (Phase 2) ? DOE Contribution: $0, Cost Share Contribution: $2,150,656
Well Drilling and Completion (Phase 3A) ? DOE Contribution: $8,220,765, Cost Share Contribution: $1,627,154
Production Field Trial (Phase 3B) ? DOE Contribution: $7,372,419, Cost Share Contribution: $9,284,776

Planned Total Funding: $28,944,148
DOE Contribution: $15,593,184 (fully obligated)
Cost Share Contribution: $13,350,964

Contact Information:
NETL Hydrate Program Technology Manager ? Ray Boswell (Ray.Boswell@netl.doe.gov or 304-285-4541)
NETL Project Manager ? Richard Baker (Richard.Baker@netl.doe.gov or 304-285-4714)
ConocoPhillips ? David Schoderbek (David.A.Schoderbek@conocophillips.com or 907-265-6010)
If you are unable to reach the above personnel, please contact the content manager.

Additional Information
In addition to the information provided here, a full listing of project related publications and presentations as well as a listing of funded students can be found in the Methane Hydrate Program Bibliography [PDF].

Semi-Annual Progress Report [PDF-5.64MB] - Period Ending 6-30-12

Semi-Annual Progress Report [PDF-1.79MB] - Period Ending 12-31-11

Semi-Annual Progress Report [PDF-25.2MB] - Period Ending 6-30-11

Semi-Annual Progress Report [PDF-2.00MB] - Period Ending 12-31-10

Semi-Annual Progress Report [PDF-4.25MB] - Period Ending 7-31-10

Quarterly Progress Report [PDF-69KB] - Period Ending 12-31-09

Experimental Hydrate Formation and Gas Production Scenarios Based on CO₂ Sequestration [PDF-144KB] - Proceedings of the 6th International Conference on Gas Hydrates (ICGH 2008)

Quarterly Progress Report [PDF-558KB] - Period Ending 9-30-09

Quarterly Progress Report [PDF-1.50MB] - Period Ending 6-30-09

Quarterly Progress Report [PDF-4.93MB] - Period Ending 3-31-09

Quarterly Progress Report [PDF-677KB] - Period Ending 12-31-08

Kickoff Meeting Presentation [PDF-891KB]