The overall objective of this effort is to further enhance earlier-developed numerical simulators, and to use them to perform studies on the characterization and analysis of recoverable resources from gas hydrate deposits, the evaluation of appropriate production strategies for both permafrost and marine environments, and the analysis of the geomechanical behavior of hydrate-bearing sediments, in addition to providing support for DOE’s hydrate-related activities and collaborative projects.

Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA 94720

Methane hydrates are solids in which water forms a rigid lattice containing a guest molecule, methane. They occur ubiquitously along the continental shelves and slopes throughout the world, as well as in subduction zones in the Pacific, the abyssal depths of the Gulf of Mexico, the Caribbean, and in on-shore permafrost regions. The concentration of methane per unit volume of water can be very large; 1 cubic meter (m³) of fully saturated hydrate contains 164 m³ of methane gas at standard temperature and pressure.

Current estimates of the worldwide quantity of hydrocarbon gas hydrates range between 1015 m³ and 1018 m³. Even the most conservative estimates of the total quantity of gas in hydrates may surpass (by a factor of two) the energy content of the total fuel fossil reserves recoverable by conventional methods. The magnitude of this resource could make hydrate reservoirs a substantial future energy resource. Although the current energy economics cannot support gas production from hydrate accumulations, their potential demands evaluation.

This effort will continue prior LBNL studies on the characterization and analysis of recoverable resources from gas hydrate deposits with a current focus primarily on further evaluation of the production potential of offshore Indian hydrate deposits, the planning of future production field tests in Alaska, and an analysis of post-production hazards.

The research will support the hydrate scientific community by making available the fastest and most advanced numerical simulation capabilities for the solution of the difficult problems of stability, characterization, and gas recovery from methane hydrate deposits. Additionally, it will allow researchers to recommend production strategies and well designs to enable gas production from a wide variety of hydrate-bearing geologic settings and methods to alleviate potential geomechanical problems related to gas production.

Budget Period (BP) 1

• LBNL released latest version of the coupled TOUGH+HYDRATE/Millstone flow-geomechanical simulators (documented in three papers in Transport in Porous Media)
• LBNL lead one of five test problems for the International Gas Hydrate Code Comparison study, and contributed to the subsequent publication from the study
• Researchers created a machine-learning based multiphase properties representation for water-methane-hydrate system for consideration as a self-teaching reduced-order model
• The team initiated design support for a DOE field test on the Alaska North Slope
• LBNL Published five new peer-reviewed papers and gave four presentations documenting FWP results

Please see the project page for ESD12-010 to view accomplishments from previous, related efforts.

Efforts under BP 1 of the project are nearing completion and the project has been revised to include additional activity to be conducted during FY2020. Activity in BP 2 of the project is focused around the use of numerical simulation tools to obtain engineering data needed for the design and execution of U.S. DOE-supported activities. The primary emphasis of the study will be the planned long-term field test of gas production from permafrost-associated hydrate deposits in Alaska in an effort to provide estimates of the expected fluid production rates (necessary for sizing field equipment) of the overall system behavior and of its geomechanical response in the course of the long-term production.

$900,000

$0 

NETL – Richard Baker (richard.baker@netl.doe.gov)
LBNL – George Moridis (gjmoridis@lbl.gov)