DE-NT0006553

Goal
The goal of this project is to define, plan and conduct a field trial of a methane hydrate production methodology whereby carbon dioxide molecules are exchanged in situ for the methane molecules within a methane hydrate structure, releasing the methane for production. The purpose 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

Background
The Energy Information Administration (EIA) forecasts world-wide natural gas consumption to increase from 99 Trillion Cubic Feet (TCF)/year in 2004 to 164 TCF/year by 2030. For the United States, the EIA forecasts an increase in consumption from 22 TCF/year to 26 TCF/year by 2030. With just 209 TCF of proved reserves, the U.S. will have to import a significant percentage of its energy requirements and/or find new domestic sources. Against this backdrop of supply constraints, the challenge of managing carbon dioxide has now become an urgent policy and business consideration.

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 Gulf of Mexico at 21,000 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 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 carbon dioxide for methane in the hydrate structure; a process that releases the methane molecules for production purposes (Graue et al., 2006; Stevens et al., 2008). Key observations in those studies include the rapid rates of carbon dioxide - methane 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 does not involve the release of free water to the pore system. Instead, the process appears to dissociate and reform 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, sustainable methane hydrates production technology at a site on the Alaska North Slope.

Potential gas hydrate accumulations on the Alaska North Slope, mapped by the US Geological Survey

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.

If this initial field trial is successful, the stage will be set for the larger-scale, longer-term tests needed to advance viable production technologies for methane hydrates. The exchange technology could prove to be a critical tool for unlocking the methane hydrate resource potential in a manner that minimizes adverse environmental impacts such as water production and subsidence while simultaneously providing a synergistic opportunity to sequester carbon dioxide.

Accomplishments
Project was initiated October 1, 2008. There are no technical accomplishments under the project to date.

Current Status
Project was awarded September 30, 2008 with a start date of October 1, 2008. The project is to be carried out as a 27 month / 3 Phase effort.

Planned activity within Phase 1 is to include:

• Identification of a suitable location to execute a field trial to test the viability of the gas hydrates production technology process which exchanges carbon dioxide for the methane molecules in the gas hydrates clathrate structure.
• Negotiation with site ownership partners as required to obtain the necessary permissions to execute the trial on the chosen site.
• Identification of any synergies to be realized by executing the trial in association with other planned ANS field activities.

Phase 2 is slated to initiate in April 2009 (assuming successful completion of Phase 1 and approval by DOE and COP to proceed to Phase 2). Phase 2 is to include:

• Development of a detailed plan for field testing of the CO2 / CH4 exchange production methodology.
• Generation of pre-drill numerical models to estimate well and hydrate reservoir behavior during drilling and production testing.

Phase 3 is planned for initiation in January 2010 (assuming successful completion of Phase 2 and approval by DOE and COP to proceed to Phase 2). Phase 3 is to include:

• Field validation of carbon dioxide-methane exchange mechanism results determined from laboratory tests, and quantification of the extent of carbon dioxide-methane exchange that occurs in a single well test mode.
• Measurement of carbon dioxide injectivity into a hydrate-saturated reservoir.
• Identification of next steps in the validation process (i.e. how this process could be advanced to a multi-well test and onwards to commercialization).

Project Start: October 1, 2008
Project End: December 31, 2010

Project Cost Information:
Phase 1 - DOE Contribution: $81,130, Performer Contribution: $1,035,974
Planned Phase 2 - DOE Contribution: $1,514,800, Performer Contribution: $1,346,233
Planned Phase 3 - DOE Contribution: $10,269,800, Performer Contribution: $1,772,563
Planned Total Funding (if project continues through all project phases):
DOE Contribution: $11,865,730, Performer Contribution: $4,154,770

Contact Information:
NETL – Richard Baker (Richard.Baker@netl.doe.gov or 304-285-4714)
ConocoPhillips – David Schoderbek (David.A.Schoderbek@conocophillips.com or 907-265-6010)