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Gas Goes Solid
Roland Piquepaille writes "This innovation from Japanese researchers can potentially revolutionize the energy distribution sector. Instead of transporting liquid gas, they changed gas into a solid material which is easier, safer and cheaper to distribute. Technology Review has the story. "Rather than extracting methane from hydrates, they want to turn methane into hydrates -- essentially, transforming the colorless and odorless gas into small pellets that can be easily stored, transported, and eventually turned back into natural gas. A few months ago Mitsui, in partnership with Osaka University, opened a demonstration plant near Tokyo to promote the concept and show that it works." Check this column for an analysis."
A few questions though -
Maybe some of you who got to the article could answer these for me.
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Assuming that all the hurdles around the process can be overcome, and it turns out to be finacialy sound, this may very well be the start of a revelution as far as energy distribution goes. Something needing just -10C to distrebute... heck, I could store a pile outside in the winter and just carry 'natural gas' inside in a bucket. Come summer, whatever remains there was would just evaporate away (I assume) safely. Methane - which is the main component of natural gas - is a quite efficient fuel for a properly designed internal combustonengine, or you could feed it to a fuelcell.
I missed a few details however... just how do you go from solifed gas and back to gaseous gas? Is it just a matter of heating them above -10C, or? Can anyone offer any inisght on this? Because if it's a realtively easy process, I can easily imagine these pellets beeing used for energydelivery in cars, homes, cabins, laptops (well, maybe not for a few years) etc etc ad nasaum.
...and then there is the 'other uses' this stuff can have... If you built a bomshell much like a thermos, you could just fill it up with pellets, add a bustercharge and get yourself a nice FAE-bomb...
Oh, gotta qoute this bit of the article (emphasis mine);
Norwegian petroleum engineers first proposed the idea after comparing the transport economics of liquid natural gas to natural gas hydrates, knowing that hydrates could store large amounts of natural gas in a small space.
Everything in the world is controlled by a small, evil group to which, unfortunately, no one you know belongs.
Heat shock, it's called. When the temperature of your freezer goes up by even a fraction of a degree (and it need not go anywhere near as high as 0 degrees celsius), some of the ice melts. When the temperature drops again, it re-freezes, but in a slightly different location. That's why ice cream (especially the really expensive stuff, that doesn't have many or any stabilizers like guar gum in it) will develop that coating of ice crystals after it sits in the freezer a while. The ice is migrating from inside the ice cream to the surface.
Now, what I have GOT to wonder is this...what effect might this have on ice pellets that contain lots and lots of tiny bubbles of methane??
For your security, this post has been encrypted with ROT-13, twice.
Methane hydrates are not particularly high-energy-density fuels- wouldn't be suitable for automotives, for example-but the bigger a store the easier it is to keep cold (lower surface area to volume ratio) so I guess they could actually be useful as a way of storing large amounts of gas economically and safely, the role they are basically playing on the seabed right now.
Basically, I just don't get the Japanese argument. Is it really going to be cheaper to transport several ordinary refrigerated trucks of methane hydrate than one very cold truck of liquid methane? It looks as if the technology might be more of a way to stockpile large reserves of gas. As electricity generation in many parts of the world is increasingly gas-fired using turbine generators, perhaps this is a way to protect fuel reserves and generator capacity better from terrorists.
Panurge has posted for the last time. Thanks for the positive moderations.
2) When you break the hydrate down, you have methane and water. You have to do something with the water - dump it on the ground, feed it into the engine to be vaporized, something.
Along these grounds, why not recycle the water to a) cool the engine itself and b) drive a small turbine for added electrical power generation. Perhaps, this additional energy can be applied to a fly-wheel assembly for quicker accelleration.
If I was at work today, I'd fire up the LNG simulations to see exactly how many scf's of natural gas will fit in a cubic foot of LNG. I'm willing to bet it's more than 180. So you'd have to transport much more hydrate than LNG for an equivalent amount of natural gas.
Also annoying that they mention nothing about pressure, as the fun way to get hydrates that I know about is to flash a high pressure stream of natural gas with a bit of water across a valve to lower pressure. Hydrates form and plug up the valve. Not a good thing, But the point is that pressure=compression costs. Nobody ever seems to give lifecycle energy costs for these new & improved technologies. And yes, I realize they are using a tank reactor, but I bet there are still some decent pressures involved to get reasonable yields.
LNG has always been borderline on whether it makes economic sense. Places like Trinidad and Qatar are into it because they have such huge natural gas supplies in relation to their oil reserves that they can build huge plants and get some economy of scale. Customers are places like Japan (hence this bit of research) and the U.S. believe it or not. Latest numbers I heard are that LNG is competative with pipeline natural gas at about $4/MMSCF, depending on how far you have to ship it. With the strong prices of the last couple of years, the pace of projects is accelerating.
Laugh while you can, monkey boy!
Actually methane hydrate is much better for transportation than liquid methane for two reasons.
First, it actually contains more energy per unit volume than liquid methane.
And second, it is much more difficult to liquiefy methane than to form the hydrate phase. Liquid form requires very very low temperatures, and very high pressure, while the hydrate phase can be attained at around the freezing point at much lower pressures.
Transporting methane in the hydrate phase is very attractive for countries that don't have their own power sources (southeast Asia). 1 cubic metre of methane hydrate holds 160 cubic metres of gaseous methane.
However, the infrastructure to use it efficiently is still under heavy development so it'll be a while before we see methane hydrate being used on a large scale.
had a good show about these methane type pockets on the bottom of the ocean. I think they were trying to explain bermuda triangle stuff. anyway, They said the pressure and coldness down on the bottom of the ocean made the methane solid. For some reason, if some of this solid methane became a gas, it'd release soo many bubbles of methane that it if there was a ship above it, the ship would lose bouyancy and sink. They showed a test done on a model ship in a testing pool, and the ship sank almost immediately.
anyway, thats one source of solid methane... Don't know how usable it'd be, being on the ocean floor, but if they could find a way to mine it, it could be a sweet deal.
It's common to store hydrogen in a tank of metal hydride chips. The tank doesn't have to be as strong, and cyrogenic temperatures aren't required. It's also far safer; if damaged, the hydrogen comes out slowly as the hydrides outgas, so at worst you get a fire, not an explosion.
It could do "a) cool the engine" and might obliterate the need to recycle coolant. As to "b) drive a small turbine" - huh? Standing water does not drive turbines AFAIK. It needs to have kinetic (waterjet) or potential (waterfall) energy.
I'd say piping gas is safer than trucking it, unless your pipelines are very exposed to trucks ;).
As for car vs plane safety- depends on whether you are measuring per distance, trip, travel time etc.
http://www.teemings.com/issue07/safety.html
Hydrates are quite interesting.
... and guess what conditions predominate in undersea pipelines?
Right out of College about 13 years ago I joined one of those huge Oil Companies and the main thing I did there for 2 years was study gas hydrates. The reason we studied them was in order to *prevent* their formation which is the opposite of what this article talks about. The problem with hydrates in the oil business is that under high pressure and low temperature they form
When oil comes from the formation, it is almost always mixed with water and some varying amount of gas or other hydrate forming HCs. Everything is fine up the wellbore and near the wellhead, but not too far away from the wellhead the fluid starts getting cold and these solid particles form. They can clog a pipeline if you don't take countermeasures. One is to run a device called a "pig" through the pipeline to clean them out. Another is to install insulation, heated lines, or inject lots of chemicals like MeOH to suppress the hydrates. But all of these things start increasing the production cost and/or decreasing capacity.
So our research looked into creating chemicals that you could inject in very small volumes near the wellhead to inhibit the formation of hydrates.
Anyway, all this hydrate study did make people think about the application of hydrates in the transport of natural gas (NG). I think it's a very interesting idea. Currently to get NG from a remote place to market, you need lots of big expensive gas turbines driving massive refrigeration equipment to create Liquified NG (LNG). Then you need these huge, wild looking LNG tankers. Then you need special port facilities to handle the super-cold LNG. The up front capex is so massive (think 10 billion plus for many potential projects) that no one just pays that upfront hoping the customers will show up. No. You get agreements on paper stretching out 30 years with customers and only THEN do you give the green light to the project.
Hydrates certainly wouldn't need near the compressor/turbine expense of LNG development, and there might be a sweet spot in terms of pressurization and temperature you might strike. However the rest of the economics I'm not too sure about. If most of the cost of a project is the tankers and you need a lot more of them for Hydrate, then you might be better off with LNG. The other huge thing in LNG's favor is that we know it works and can calculate a cost.
One interesting idea I saw floated once was the creation of hydrate subs. Huge deepsea vessels that would be able to stay cold and high pressure just by virtue of being well below the sea surface where those conditions are natural. Now unlike a typical sub, these guys would never surface and so would not need thick walls to handle pressure differences inside and out.
Imagine one of these things scooping up hydrate from the ocean floor and carting it off to a disassociation plant on the seabed (preferably in a subsea canyon as closs to the coast as possible) that evaporated the hydrate gas into a regular gas pipeline.
dave