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ConocoPhillips to drill for gas hydrates Well planned in Alaska’s Prudhoe Bay field to test ‘promising technology’ involving exchange of methane, carbon dioxide molecules Wesley Loy For Petroleum News
ConocoPhillips Alaska is seeking state and local clearance to drill a well in the Prudhoe Bay unit to conduct a production test for natural gas hydrates.
In a Dec. 28 letter to the Alaska Department of Natural Resources and the Barrow-based North Slope Borough, the company said it plans to build an ice pad for the project adjacent to Prudhoe Bay L-pad.
Construction would begin Feb. 1, the letter said. The drilling and well completion phase of the Ignik Sikumi No. 1 project will occur in 2011, with the actual well test to follow in 2012. The entire project would wrap up in May 2012.
“The purpose of this project is a trial to drill for gas hydrates,” the letter said. “This well and associated work has been approved in a Ballot agreement between all Working Interest Owners of the Prudhoe Bay Unit.”
Other Prudhoe owners include BP, ExxonMobil and Chevron.
Innovative test Gas hydrates are believed to be a fabulous resource across Alaska’s North Slope. The U.S. Geological Survey has estimated 85 trillion cubic feet of undiscovered, technically recoverable gas resources exist within hydrates in northern Alaska.
That dwarfs the 35 trillion cubic feet of known conventional gas in Prudhoe Bay and other North Slope fields.
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.
The U.S. Department of Energy selected ConocoPhillips to perform the first field trial of a “promising technology” to allow production of methane from gas hydrates on the Slope, says a joint DOE-ConocoPhillips data sheet.
“This well will be drilled to gain scientific knowledge and test a patented production technology which was developed by ConocoPhillips and the University of Bergen (Norway),” the data sheet says. “ConocoPhillips and the University have been developing this technology since 2003. This trial represents the first experiment outside a laboratory of this production technology in which a carbon dioxide molecule is exchanged for the methane molecule locked up in the hydrate’s structure. The methane gas is produced, and the carbon dioxide is sequestered inside the hydrate structure.”
The data sheet continues: “The trial will answer two basic questions: First, does the laboratory-proven exchange mechanism work in the field, with minimal sand and water production? Secondly, what kind of rates and exchange efficiency is demonstrated? Although ConocoPhillips has repeatedly demonstrated this technology in a laboratory setting, this will be the first real-world test. The results of this trial will allow ConocoPhillips to establish a forward-phased development plan for the technology, including additional field trials.”
Past hydrates drilling ConocoPhillips isn’t the first to target Alaska North Slope hydrates.
BP in February 2007 drilled a DOE-funded $4.6 million test well in the company’s Milne Point field. Further spending has occurred since.
The 3,000-foot well targeted a prospect called Mount Elbert, named for the highest peak in Colorado, home state of a USGS hydrates expert involved with the project.
According to a Nov. 4, 2010, progress report BP submitted to DOE’s National Energy Technology Laboratory, the Mount Elbert site “was selected to drill a stratigraphic test well to acquire a full suite of wireline log, core, and formation pressure test data. Drilling results and data interpretation confirmed pre-drill predictions and thus increased confidence in both the prospect interpretation methods and in the wider ANS gas hydrate resource estimates.”
The progress report discusses other hydrates research including an encouraging 2008 production test in Canada’s MacKenzie Delta, but notes “the economic viability of gas hydrate production remains unproven.”
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