|
Hydrate test well finished at Prudhoe Ignik Sikumi project is partnership between Conoco, Department of Energy; goal is to sequester CO2 while producing methane Wesley Loy For Petroleum News
A well to test innovative technologies for producing methane gas from hydrate deposits has been “safely installed” on Alaska’s North Slope, the U.S. Department of Energy announced May 17.
The well is a partnership between ConocoPhillips and the DOE Office of Fossil Energy’s National Energy Technology Laboratory.
ConocoPhillips spud the Ignik Sikumi No. 1 well in late March at a site adjacent to L-pad in the Prudhoe Bay field. The company is a major owner of the field.
The DOE selected ConocoPhillips to perform the first field trial of production technology that involves exchanging carbon dioxide molecules for the methane molecules locked up in the hydrate’s structure.
Hydrates are a solid, crystalline form of gas, usually methane, mixed in sandstone and water. A combination of cold and pressure keeps the gas as a solid.
Gas hydrates are believed to be a huge resource across northern Alaska, amounting to tens of trillions of cubic feet, the U.S. Geological Survey estimates.
‘Fire in the ice’ Ignik Sikumi is Inupiaq for “fire in the ice,” the DOE said.
The agency said “a fully instrumented well” is now in place and “will be available for field experiments as early as winter 2011-12.”
The well will test a technology that involves injecting carbon dioxide into sandstone reservoirs containing methane hydrate.
“Laboratory studies indicate that the CO2 molecules will replace the methane molecules within the solid hydrate lattice, resulting in the simultaneous sequestration of CO2 in a solid hydrate structure and production of methane gas,” the DOE said.
The recently completed operations on the Ignik Sikumi project include “the acquisition of a research-level suite of measurements through the sub-permafrost hydrate-bearing sediments,” the agency said.
“The data confirm the occurrence of 160 feet of gas-hydrate-bearing sand reservoirs in four separate zones, as predicted, and provide insight into their physical and mechanical properties. An array of down-hole pressure-temperature gauges were installed in the well, as well as a continuous fiber-optic temperature sensor outside the well casing, which will monitor the well as it returns to natural conditions following the drilling program.”
What’s next In coming months, the data will be reviewed to determine the optimal parameters for future field testing, the DOE said.
“Current plans are to re-enter the well in a future winter drilling season, and conduct a 1-2 month program of CO2 injection and well production to assess the efficiency of the exchange process,” the agency said.
Following those tests, the remaining time available before the spring thaw might be used to test reservoir response to pressure reduction in the wellbore, the DOE said.
This “depressurization” method of methane production recently proved effective during short-term testing conducted by the governments of Japan and Canada at a site in northwestern Canada, the agency said.
ConocoPhillips isn’t the first to target North Slope hydrates.
BP in February 2007 drilled a DOE-funded test well in the company’s Milne Point field.
| 