|Properties of Hydrate-Bearing Sediments Subjected to Changing Gas Compositions
||Last Reviewed 12/11/2013
The objective of this research is to measure physical, chemical, mechanical, and hydrologic property changes in methane hydrate-bearing sediments subjected to injection of carbon dioxide and nitrogen.
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA 94720
A number of studies have investigated the impact of injecting carbon dioxide (CO2) and CO2-nitrogen (N2) mixtures into methane hydrate for the purpose of sequestering CO2 and releasing methane (CH4), and review articles have been published summarizing the literature. Most of these studies have investigated the fundamental physical/chemical nature of the exchange of CO2 and/or N2 with CH4 in the clathrate. These studies have helped identify the limits of the effectiveness of CO2 injection into methane hydrate for the purposes of methane production and CO2 sequestration.
Few studies have examined the hydrologic and physical/mechanical property changes that occur during a hydrate composition change. In the few studies that have been conducted, researchers did not measure hydrologic properties; quantification of the effluent gas was crude and performed over a limited range of conditions (mostly dry hydrate) and failed to address important reservoir issues such as pressure increase upon injection and the effect of changes in gas composition in a system where the gas composition varies.
This research will investigate processes associated with the injection of N2, CO2, and mixtures of these gases into methane hydrate-bearing porous media under non-stirred batch and flow-through conditions, and will attempt to quantify the exchange kinetics of the N2 and CO2 replacement into methane hydrate using flow-through reactors and breakthrough curve analysis. Permeability will be measured to detect changes, and geophysical property changes will be measured using either the Split Hopkinson Resonant Bar apparatus or a flow-through vessel with p- and s- wave transducers in the end platens.
The primary benefits of this lab-based research are improved empirical relationships among physical, chemical, mechanical, and hydrologic property changes in methane hydrate-bearing sediments subjected to injection of CO2and N2, which will assist in understanding the results of hydrate production field test data.
Accomplishments (most recent listed first)
- Completed and documented results of a series of lab tests to monitor changes (gas exchange rates, permeability, and geomechanical properties) in CH4 hydrate-bearing samples exposed to a N2/CO2 gas mixture.
- Completed design and construction of an experimental system to measure kinetics of gas exchange in hydrate-bearing sediments.
- Established a new laboratory set-up (including new CT scanner) capable of performing and monitoring hydrate exchange kinetics experiments.
- Please see the project page for ESD05-048 to view accomplishments from past, related efforts.
Current Status (December 2013)
Budget period 2 activities are ongoing. A topical report on changes in hydrologic and geophysical properties of porous media containing CH4 hydrate, free water, and gas subjected to CO2/N2 flooding is scheduled for completion by early spring 2014. Additionally, project personnel will continue to develop approaches for the grain scale computation of hydrate-bearing sand properties from Micro CT sample images, report on the results of this effort by early summer 2014, and post reports of research in each of these areas to the website upon completion.
Project Start: June 1, 2012
Project End: June 30, 2014
Project Cost Information:
DOE Contribution: $210,000; Recipient Contribution: $0
NETL – Richard Baker (Richard.Baker@netl.doe.gov)
LBNL –Timothy J. Kneafsey (firstname.lastname@example.org)
If you are unable to reach the above personnel, please contact the content manager.
Research Performance Progress Report [PDF-140KB] July - September 2013
Topical Report : Behavior of Methane Hydrate Bearing Sediments Subjected to Changing Gas Composition [PDF-1.55MB]
Graphical representation of system to measure kinetics of gas exchange in hydrate-bearing sediments
Experimental system shown with reactor vessel inside of CT scanner