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Add To DockHydrates Inflate Energy Picture

Technology has a way of opening doors up wide. Just five years or so ago, petroleum producers were just discovering that the combination of horizontal drilling and hydraulic fracturing could open up pockets of natural gas in ways they hadn’t done before.
Now, a discovery deep below the seabed is showing that same technology may be the key to opening vast resources of methane hydrates, thus adding years and years of natural gas to the energy mix.
A gas hydrate is a solid compound in which a large amount of methane is trapped within the crystal structure of water. Scientists once thought these hydrates only existed in the outer regions of the Solar System, but significant deposits have been found under sediments on Earth’s ocean floor.
Scientists have found the largest deposits in low-permeability muds beneath the Arctic permafrost. However, a key researcher at the Dept. of Energy’s Technology Lab reported in the journal Science that newly found beds of these gas hydrates have been uncovered off the shores of Japan and Alaska. These methane hydrates happen to be located in sandy sediment and may be easier to extract using current technology. More research is needed since the gas clusters are highly unstable under pressure and temperature changes. It can be difficult to extract the methane without also destroying it.

Two key barriers remain to finding out whether the hydrates trapped in the sandy sediments will be a sought-after commodity, even though they may be easier to obtain. The first is to find out how much of this hydrate is actually in these sandy sediments, and is it enough to pursue. The second is whether the hydrates will give up enough natural gas to make the exploration a viable commercial expense.
Other gas hydrate consultants agree with the Dept. of Energy.
“With hydrates, we don’t know what that rate will be, what is the ultimate recovery per well, how much gas will that well be able to produce on a daily basis, the longevity of the well,” said Arthur Johnson an international gas hydrate consultant. “We really don’t have a good understanding of that.”
The sector says it would not move forward without a long look at the environmental aspects either.
“We need to figure out what is the optimum way to go about producing these in a way that is safe for the facilities and the environment,” said Johnson. “How do you design wells that give you commercial rates while maintaining safety and environmental quality?”
Production tests are being planned for sites in Alaska.

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