Methane hydrate test successful

While natural gas discoveries in the US are not necessarily anything to crow about with gas prices hovering in the "dismal" range, a recent field trial might uncover a completely untapped form of natural gas that will make shales pale in comparison.

The US Department of Energy (DOE) announced recently that the US and Japan have successfully completed a field trial of methane hydrate production technologies on Alaska's North Slope. The DOE partnered with ConocoPhillips and the Japan Oil, Gas, and Metals National Corp. to test natural gas extraction from methane hydrate by injecting a mixture of CO₂ and nitrogen into the formation. The mixture promoted the production of natural gas, and ongoing analysis will determine if this method also can be used to store the CO₂ in the reservoir.

Why is this important? Because methane hydrates are by far the most abundant hydrocarbon resource on the planet, with some pundits estimating that the size of the reserves may exceed the energy content of all other fossil fuels combined. In addition to the Arctic, they are commonly found in ocean sediments.

This is not a new discovery, per se – the industry has known about hydrates for years. To drillers they are a hazard and need to be studiously avoided. To many others they are an energy source that is so

challenging to produce that it will be decades before hydrate production is feasible. But the DOE project is laying the groundwork for that production now.

Methane hydrates are 3-D ice structures with natural gas locked inside and are found around the world. While the structures look like ice, simply melting the water only releases the gas into the atmosphere. Therefore, the hydrates need to be "melted" in situ.

The DOE project was the first field trial of a methane hydrate production methodology in which CO₂ was exchanged in situ with the methane molecules within the structure. The test lasted 30 days to test the depressurization phase. Previously the longest depressurization field test lasted six days.

The next stages of the research will evaluate gas hydrate production over longer durations to determine if sustained production might be economically possible. A press release from the DOE points out that this could take years but that its research into shale gas in the 1970s and '80s eventually helped pave the way for today's shale gas mania.

As part of its announcement, the DOE also is putting forth an additional research effort aimed at locating, characterizing, and safely extracting gas from hydrate formations. It is allocating US $6.5 million toward this effort. Projects will address deepwater gas hydrate characterization by direct sampling or remote sensing field programs; new tools and methods for monitoring, collecting, and analyzing data to determine reservoir response and environmental impacts related to methane hydrate production; and clarifying methane hydrates' role in the environment.

The department is requesting an additional $5 million to further hydrate research both domestically and in international partnerships. Some of this funding may go toward a longer extraction test on the North Slope on an existing gravel bed to accommodate year-round production. "Such an effort would again require engaging private sector and international partners," the press releases states.

North America may not need a new gas discovery right now. But if projects like these prove that hydrates can be economically produced, methane hydrates might be the 2032 version of the shale gale.