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Japan Extracts Natural Gas From Frozen Methane Hydrate
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.'"
The problem is transporting it. Transporting liquids (oil) is easy, you pump it through pipes to tanks. Transporting gas is slightly harder as you pump it in air-tight pipes to air-tight tanks.
Transporting room temperature solids is a moderately hard, you shovel it and truck it.
But frozen methane is the worst. It is solid when left alone, but turns to gas at room temperature. Worse, it is almost always at the bottom of the ocean.
If they solved this problem, great. But we don;t know they did that, because they were not very clear at all.
In my experience there is a simple explanation for that lack of information - very bad translation from a foreign language. Someone probably solved a rather minor technical issue about removing the frozen water, leaving the gas, but it probably did NOT solve the major 'do it underwater, at huge depths, at freezing cold temperatures, by robot' problem.
Instead of explaining that it was a minor technical victory, they left out all the details and claimed translation issues.
excitingthingstodo.blogspot.com
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
Eh, depending on some variables maybe it isn't that bad.
1. Assuming that they'd burn coal if they didn't use the methane.
2. Assuming the energy released from burning the methane is similar to the energy released from burning coal (I don't know)
then burning something that is inherently unstable like the Methane Hydrates in the oceans is far better than burning the coal. The coal is a nice stable solid at every human habitable temperature. They Hydrates aren't. If the ocean warms too much, the hydrates will just bubble out and poof, LOTS more methane in the atmosphere that didn't provide us anything useful - and we have the CO2 released from burning the coal.
So the devil is in the details, and the best solution is burning neither methane nor coal, but if you have to pick, choose the one that isn't likely to spontaneously turn into another form thus making your situation much much worse.
People in cars cause accidents....accidents in cars cause people
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
Also known as Clathrate gun
Questions raise, answers kill. Raise questions to stay alive.
If the ocean warms too much, the hydrates will just bubble out and poof, LOTS more methane in the atmosphere that didn't provide us anything useful...
Additionally, methane is 25 times more potent as a grennhouse gas. So converting that to energy and CO2 gives you energy and a net reduction in the greenhouse effect.
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
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).
excitingthingstodo.blogspot.com
Methane is less stable than CO2. Its lifetime in normal atmoshperic sunlight is about two decades. CO2 stays for thousands of years.
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.