Japan Extracts Natural Gas From Frozen Methane Hydrate 154
ixarux writes "For the first time ever, a Japanese company has successfully extracted natural gas from frozen methane hydrate off its central coast. The Nankai Trough gas field, located a little more than 30 miles offshore, could provide an alternative energy source for the island nation, reducing its dependence on foreign imports. 'A Japanese study estimated that at least 1.1tn cubic meters of methane hydrate exist in offshore deposits. This is the equivalent of more than a decade of Japan's gas consumption. Japan has few natural resources and the cost of importing fuel has increased after a backlash against nuclear power following the Fukushima nuclear disaster two years ago.'"
Re:Clarity (Score:5, Informative)
Not quite. This is the first offshore demonstration of extraction, but it's been carried out successfully onshore before.
Methane Hydrates and the Future of Natural Gas - MIT Energy.
To date, these permafrost-associated deposits are the only places
where production of gas from verifiable dissociation of gas hydrates has ever been documented.
Short-term (i.e., several days) production tests were carried out at the Mallik well in the
Mackenzie Delta area of Canada in 2002 and 2007 (Dallimore and Collett, 2005; Hancock et al.,
2005; Takahisa, 2005; Kurihara et al., 2008) and at the Mt. Elbert (Milne Point) site on the
Alaskan North Slope in 2008 (e.g., Hunter et al., 2011).
Offshore extraction of NG from hydrates for Japan will be a tough pill to swallow for people whose country was recently trashed by tsunamis, as hydrates are associated with prehistoric massive seabed slumping. Read more here: DOE Meeting Summary: Catastrophic Methane Hydrate Release [global-war...eering.org]
Re:Clarity (Score:5, Informative)
Offshore extraction of NG from hydrates for Japan will be a tough pill to swallow for people whose country was recently trashed by tsunamis, as hydrates are associated with prehistoric massive seabed slumping. Read more here: DOE Meeting Summary: Catastrophic Methane Hydrate Release [global-war...eering.org]
Also known as Clathrate gun [wikipedia.org]
Re:Article sucked (Score:2, Informative)
The problem is not extracting methane from ice or mining it at the bottom of the ocean. The problem is that these deposits are highly unstable, prone to spontaneous emissions and landslides. It is extremely unstable terrain.
You can't even put a ship above a major deposit and just start digging whatever you want. If you screw up and methane bubbles up, the bubbles will sink the ship - Bermuda Triangle and all that is prime example of how ships can just "disappear" because of methane releases from these "fire ice" deposits. One minute your ship is buoyant, the next it sinks..
Everyone knows how to extract this methane. Dig up the ice, melt it/mash it, and boom, you have gas. The problem is that when you start digging, you can cause a major problems, including tsunamis from underwater landslides and loss of equipment as it gets buried under a few million tons of rock.
As for deposits on land, they are spread out over large areas. It is like mining a garbage dump for gas - you don't get much gas from it before you have to move on.
Re:Article sucked (Score:5, Informative)
The article really sucked, so I went looking for another [telegraph.co.uk], even though it was only slightly better.
The major improvement is in depressurizing the hydrate so that the gas will boil off. They don't have a robot at those depths, the work is done at the end of a drill string
Re:Seems like a good step (Score:5, Informative)
That seems better. "More than a decade" sounds too short term of an investment.
According to the NY Times, the overall gas available may be more like 100 years' worth:
Jogmec estimates that the surrounding area in the Nankai submarine trough holds at least 1.1 trillion cubic meters, or 39 trillion cubic feet, of methane hydrate, enough to meet 11 years’ worth of gas imports to Japan.
A separate, rough estimate by the National Institute of Advanced Industrial Science and Technology has put the total amount of methane hydrate in the waters surrounding Japan at more than 7 trillion cubic meters, or what researchers have long said is closer to 100 years’ worth of Japan’s natural gas needs.
http://www.nytimes.com/2013/03/13/business/global/japan-says-it-is-first-to-tap-methane-hydrate-deposit.html?hp [nytimes.com]
Re:3 days (Score:4, Informative)
How is combusting methane better than combusting other hydrocarbons?
Apparently not what the gp meant, but combusting methane (CH4) is, in fact, better than ethane (C2H6), which is better than propane (C3H8), etc. As the chain gets longer, the ratio of C/H gets higher, resulting in more CO2 being released for the same amount of energy produced.
Better article (Score:5, Informative)
It explains that the Japanese found a way to send a pipeline down to the hydrates and depressurize them. This caused some of the released methane to travel up the pipeline they had dropped to the surface, where it could be captured as a gas.
Note it does not say how much of the gas is wasted/escapes into the ocean (which might have some very serious effects). On the other hand, they left most of the ocean pressurized (obviously) so it should hopefully re-sublimate back down to a methane hydrate.
It is actually a real breakthrough, rather than a mere translation problem. That said, a lot matters about efficiency. Merely getting a gallon of methane to the surface is not a huge deal if they have to burn 3/4 of a gallon to get it up (let alone transport it to someplace useful via a pressurized gas transport ship/pipeline).
methane has shorter lifetime (Score:5, Informative)
Re:Seems like a good step (Score:5, Informative)
Taking methane out from the continental shelf and burning it ADDS greenhouse gas.
Not if it displaces burning coal. Per Kw, methane generates half as much CO2 as coal. Since AGW became an issue in the 1990's, the lion's share of CO2 reduction has been because of moving from coal to gas. Coal-to-gas isn't perfect, and it isn't a long term solution, but it works, it is cost effective, and it is actually happening in a big way . No other method of CO2 reduction even comes close. Don't make perfect the enemy of good. [wikipedia.org]