Clathrates as fuel source

Discussion in 'Chemistry' started by fishtail, Jun 29, 2007.

  1. fishtail Registered Senior Member

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  3. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    No, but will be more explicit:

    Most (I think all), multiple atom, non symetric molecules such as CO, CH4, CO2, H2O do supress the escape of IR from Earth. The IR leaving Earth is much more weakly impeded by symetric molecules (no net dipole moment) such as O2 & N2, the main components of the air. The IR´s escape from the Earth´s surface is suppressed by being absorbed. Often in the denser atmosphere where instead of almost immediate re radiation the excited energy is thermalized in a collison. Even in the very-high, low-density atmosphere where reradiation is more likely than collision, the re-radiation has essentailly a 50-50 chance of being directed back down towards Earth. I.e. they very effective supress the escape of IR radiation.
     
    Last edited by a moderator: Jul 18, 2007
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  5. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    The Clathrates in Siberia are particularly interesting. The deep sea Clathrates will probably not start releasing methane until very late in the day. Under the high pressures at the ocean depths, I believe it takes temperatures in the high 50s Fahrenheit to cause significant yields. ( please correct me if I'm wrong) But Siberia is gradually thawing out.
    In Siberia we have the situation where burning fuel may become actually environmentally friendly. As Methane is a much more effective greenhouse gas than co2, if it is going to be released it would be better to burn it.
     
    Last edited: Jul 18, 2007
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  7. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    The Japanese hope to do just that. I think you are wrong, althought many do speak of a decomposition pressure vs temperature curve. I think it is more like disolving any gas in water. I.e. at any given temperature there is saturation concentration. As the temperature is raised, the saturation concentration is less, so if already saturated (probably is) then even a one degree rise will release some gas. That is why the Japanese are already seeing methane bubble rising in very deep, high-pressure, water as stated below in bold I added.


    "... Japan Mines `Flammable Ice,' Flirts With Environmental Disaster

    Dec. 26 {in Japan already} (Bloomberg) -- Fifty-five million years ago the world's climate was catastrophically changed when volcanoes melted natural gas frozen in the seabed. Now Japan plans to drill for the same icy crystals to end its reliance on imported energy.

    Billions of tons of methane hydrate, frozen chunks of chemical-laced water buried in sediment some 3,000 feet under the Pacific Ocean floor, may help Japan win energy independence from the Middle East and Indonesia. Japanese engineers have found enough ``flammable ice'' to meet its gas use demands for 14 years. The trick is extracting it without damaging the environment.

    Japan is joining the U.S. and Canada in test drilling for methane even as scientists express concerns about any uncontrolled release of the frozen chemical. Some researchers blame the greenhouse gas for triggering a global firestorm that helped wipe out the dinosaurs.

    ``Methane hydrate was a key cause of the global warming that led to one of the largest extinctions in the earth's history,'' says Ryo Matsumoto, a University of Tokyo scientist who has studied frozen gas since 1987. ``By making the best use of our wisdom, knowledge and technology, we should be able to utilize this wisely as a new energy.''

    If successful, the gas drilling project could help Japan reduce a liquefied natural gas import bill that last year was 2.66 trillion yen ($23.3 billion). The country's LNG imports totaled 62.2 million metric tons, equivalent to 3.03 trillion cubic feet, according to the Ministry of Finance's trade report.
    ...
    Trapped within sheets of ice up to 500 meters (1,640 feet) thick is an estimated 40 trillion cubic feet of crystalline methane encased in an ocean trench called the Nankai Trough, 30 miles (50 kilometers) off the coast of the main Honshu Island.
    ...
    Exploiting the Nankai Trough depends on developing technical know-how through a test project in Canada's frozen north, says Kenichi Yokoi, team leader of the methane hydrate research project at state-controlled Japan Oil, Gas and Metals National Corp., known as Jogmec.
    ...
    The most efficient method has proved ``depressurizing,'' which requires deep bore holes being drilled into the ice sheets. Pressure within the chamber is reduced by a pump, causing gaseous methane to separate from the water and ascend to the well head.
    ...
    Commercial exploitation of methane hydrate is economically viable when oil trades above $54 a barrel, Japan's government estimated two years ago. The trade ministry is targeting 2016 to start production, corresponding with the scheduled completion of the 16-year government-led test project.

    While governments are attracted to an abundant clean fuel, drilling risks disturbing the seabed and triggering an uncontrolled release, says Matsumoto of the University of Tokyo.
    ...
    Undersea landsides triggered by volcanoes that occurred more than fifty million years ago resulted in the release of methane hydrate, contributing to global warming that lasted tens of thousands of years, says Matsumoto.

    Japan's government is promising rigorous environmental controls with gas-leakage detectors and monitoring systems in place before the scheduled test drilling in as early as 2009.
    ...
    A bigger worry is evidence that the undersea ice may already be melting. In September, Matsumoto joined a research party in the Sea of Japan to follow up on a 2006 discovery by his university colleagues of methane gas bubbles rising from the ocean floor.

    Billy T insert: Is it too late already to stop Earth from becoming a "cooler version of Venus" ? - I.e. a scalding steam atmosphere at ground level. A possibility I expressed some time ago here and in other related threads due to the strong "positive feed back" of methane adding to global warming. SEE post 12 for some details.

    ``It's ironically recurring,'' Matsumoto says. ``Extinction of living organisms has repeatedly taken place in the earth's history, and dead bodies were accumulated in soil and under the sea bed, and turned to oil and natural gas.''
    ... Last Updated: December 25, 2007 11:13 EST ..."

    Condensed by Billy T from:
    http://www.bloomberg.com/apps/news?pid=20601109&sid=aiUsVKaqDA7g&refer=home
     
    Last edited by a moderator: Dec 25, 2007
  8. cosmictraveler Be kind to yourself always. Valued Senior Member

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    The most abundant atom in the universe is Hydrogen, so why not figure out how to extract it from space and return it here to earth to use?
     
  9. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Its concentration is probably less than one atom per cubic meter. Do you have any idea how much more energy it would be required to concentrate / compress it to a standard tank of hydrogen gas pressure? - I think not or you would never suggest such a silly idea. (Not to even mention the energy the rocket will require to get there and fly around trying to "scoop some up.")
     
  10. cosmictraveler Be kind to yourself always. Valued Senior Member

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    I was thinking using a giant vacuum hose, like the space elevator idea, and suck the stuff from space down here to Earth!!

    Please Register or Log in to view the hidden image!

     
  11. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    For on topic post skip this and go to post 24 - a very serious concern about methane hydrates making life on Earth impossible etc.
    Not that I think that is even slightly realistic* or economical, I did not focus on the collection means.

    I only pointed out the compressing from one per cubic meter to more than10^30/ per cubic meter is one hell of a compression with thousands of times more energy required than obtained by oxidizing H to H2O.
    --------------------
    *to illustrate one "minor" problem, lets assume your vaccum tube "sucking" (the is no such thing as "sucking" as it is the pressure difference that moves things when you "suck") is up and working. Lets even assume that you get a million times more concentrated H2 gas down to 100 feet above the surface of the Earth inside your "vaccum tube". There the temperature gives the light hydrogen molecules more than Earth's escape velocity so back to space they go.

    You have obviously not thought about why there is no significant amount of hydrogen in the Earth's atmosphere. Plenty of hydrogen is constantly being released at the surfaces by various natural organic processes. It all is traveling fast enought to esacpe the weak gravity of Earth, but in the dense lower air does not escape before making many collisons. In your "vaccum tube" open at the top, every one that happens to be headed up just escapes into space with no collisons.

    Your whole idea of a pump sucking on essentially a "perfect" vaccum is nearly nonsense. The only pumps that work at very low presssures are spinning turbo blades that occasionally hit a molecule on its collision free path and knock it in the direction you desire it to go. To get even a milli-gram per hour of H2, these turbines of the turbo-molecular pump would need to be bigger than the entire air bus 380.

    But again, there is no need to speak of theses things - the energy for compression is far in excess of the energy collected, regardless of how it is done.
     
    Last edited by a moderator: Dec 25, 2007
  12. MetaKron Registered Senior Member

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    Is there some part of "increased albedo" that any scientist could fail to understand? Reflect the light away and you get a cooler planetary surface. The idea that Venus's clouds make it hot is extremely implausible. Earth gets half the insolation that Venus does, also.

    What really sucks here is that fantastical predictions of catastrophe gain the credibility that sober evaluation of the facts doesn't.
     
  13. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    The net effect of clouds depends upon several variables: The chemical composition of the cloud, the altitude of the cloud and its thickness, what time of day the cloud is present*, the nature of any particular matter (dark soot vs highly reflective Al2O3 dust, etc.) and size distribution which controls the dominate type of scattering (especially if in the Mie scattering ranges or smaller) and probably some some other factors. Thus it is true that scientist do not fully understand the complex thermal problem of the effect of clouds on Earth's heat balance.
    It is the very widely accepted explaination for why the surface of Venus is hotter than melting lead, despite the fact that the surface is dark without any sunlight reaching it. Most well informed believe that Venus was once only slightly warmer than Earth until this current cloud atmosphere formed.
    It is your statement that is extremely implausible or "nonsense."
    ------------------
    *About the only thing one can be completey confident in wrt the net effect of clouds is that during the night, they help Earth retain heat as there is no sunlight to reflect back into space.
     
    Last edited by a moderator: Dec 26, 2007
  14. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    Good point Metakron. I'll have to ponder on that one. Actually, it's been a long time since I posted on this thread, and I'm not sure what I meant myself! I think you may be right that the catastrophe theories are far fetched, and that the eventual results of Global warming may be relatively harmless to rich Northern countries, though even minor temperature rises will be devastating to other places.

    If we are prepared to dig in, seal our borders, and pay no attention to the wars, famine and mayhem that ensue, we could be fine.
     
    Last edited: Dec 26, 2007
  15. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Certainly possible, perhaps probable, but there is a very real possibility, quite unlikly I HOPE, the ground level atmosphere will be scalding steam. All life on Earth would then die.

    Some take comfort in the fact that both global temperatures and CO2 levels have been higher than they are today and think this implies the Earth converting to a "cooler version of Venus" is therefore impossible. While that may be true, those facts do rule out that possiblity as they do not consider the rate of change, which is unprecidented in Earth's history.

    Man is rapidly increasing the atmospheric CO2, much faster than every before. CO2 is highly soluable in water, but the removal of it from the atmosphere is a relatively slow process compared to the rate man is adding it to the atmosphere. If the process of adding CO2 to the air and absorption of it by the oceans were proceeding slow enough for these two to be essentially in thermodynamic equlibrium, as it has in the past, then the current oceanic concentration of CO2 corresponding to the current atmosphereic concentration would be higher. I.e. the oceans are now lagging behind the atmosphere in CO2 concentrations.

    Thus the oceanic processes that quasi-permanately store carbon (for example formation of calcium carbonate shells as now seen in the "white cliffs of Dover" etc.) are not proceeding as rapidly as in the past. Thus, the oceans, with a little warming, can give back some CO2 to the air as only the upper layers are near equlibrium concentrations.

    If you know anything about feed back systems, you know that the RATE of signal growth around the loop is the important factor in determining whether or not a system is stable. So long as the "loop gain" remains below unity the set point will just change but not "run away" in self accelerating instability.

    The Earth, like Venus, has two stable states. Venus was once in the same cooler stable state Earth is now in (I.e. not covered by permanent clouds that serve as a "thermal blanket") Venus switched to the "hot stable state" and it is certainly possible that Earth could too. If the RATE man is adding green house gases, mainly CO2, combined with other natural sources (and perhaps even a solar intensity increse) etc does boost the loop gain above unity that may, and probably will, happen.

    Note that IF the methane stored in Calhates is released slowly, it contributes very little to the global warming as methane is not long term stable but oxidized and UV destroyed in the atmoshpere; however, with man accelerating the rates more than ever before, no one knows what will be the effect on the methane concentrations in the atmosphere. - Quite likely they will reach levels never before achieved (at least since green plants converted Earth's original reducing atmosphere to an oxidizing one).

    Also "bad news" is the fact that on a molecule by molecule basis, methane is at least ten times worse green house gas than CO2.

    I am sorry my posts is long but the problem is complex. MetaKon's simple one sentence is basicly nonsense, for reasons I explained in my prior post, but I admit it is more comforting that the complex truth.
     
    Last edited by a moderator: Dec 26, 2007
  16. MetaKron Registered Senior Member

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    Repeating myself: Far-fetched theories seem to be believed sooner than sober science. It's always this end of the world garbage, too. In my mind that disqualifies said believers from making any policy, whether it's about what kind of light source I use, what I eat for dinner, or what kind of sex I have. It's always "the end of the world" if they want me to do something to please them.
     
  17. MetaKron Registered Senior Member

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    Good God, Billy. Sometimes you make sense but sometimes you don't know where to end your posts.
     
  18. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    It is very "sober climatic science," which indicates the possibility (with currently unknown probability as there are many variables and some still ill defined physics) that Earth can be switched to the other thermally stable state. - The “hot state” with a scalding steam atmosphere, (at least until the oceans boil away into space as they did on Venus did long ago.)

    To ignore this low probability possibility is much more irresponsible than to ignore other low probability events such as Earth being struck by moderate sized asteroid or explosion of nuclear power plant. "More irresponsible" because of these three, Earth switching to the hot stable state is the only event certain to make the Earth sterile. – I.e. terminate all life on Earth.

    I do not know if the probability of Earth switching to the "hot stable state" is 0.1 or 0.00000001, but I do not think it wise to stick head in sand and pretend it is exactly zero. Fortunately, there are responsible scientists looking into why Venus switched to the hot stable state. Several space craft have been sent to Venus and many radar and spectrographic studies of it have been made in the effort already to understand the dynamic thermal balance of plants like Earth and Venus, especially focused on the climatic factors they share in common, which are not shared by Mars with its thin atmosphere and lower solar flux, and higher orbit eccentricity. (Mars is of little use because of these factors it the effort to better define the probability of Earth switching to the hot stable state.)
     
  19. MetaKron Registered Senior Member

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    Billy, you don't have to do any pretending to know that the scientists don't have a fucking clue about global warming. They can't even reliably predict whether it is going to snow tonight or have any idea how much, so they can't possibly predict global trends with any degree of reliability whatsoever.
     
  20. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I can generally agree with that, but one can be certain that Earth does have two stable states: One like the present with minor variations in averager temperature and one much, much hotter with dense steam atmosphere, some what like Venus, but not so hot that lead would be liquid on the surface. What is very ill known is under what conditions the Earth will switch to the hot stable state, as Venus did long ago.

    I fear there is a non zero probability that the unprecedented RATE at which man is releasing green house gases, may exceed the rates at which natural processes can make restorations back towards the present cooler state so that the net process becomes a runaway instablity that does switch Earth to the hot, lifeless, stable state.
     
  21. MetaKron Registered Senior Member

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    We cannot be certain of any such stable state.
     
  22. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Why do you assert that, when we have the example of Venus which has switched from the cooler, Earth like state, to the hotter one it has today? If you are just saying that nothing is certain, not ever that there is an Venus or Earth, then I agree, but most people especially physicists and specialist in planetary climate stability states do accept that there are two stable states for both Earth and Venus. (The cooler one with a atmosphere which permits IR to escape from the surface, and a hotter one which does not. I.e. in the hot stable state ALL THERMAL RADIATION leaving the surface is absobed in the thick clouds of the atmosphere. Only the much cooler "top of the atmopsphere" radiates energy back into space.

    In the hot stable state of Earth, then main component of the atmoshpere is H2O (steam). The H2O molecules currently in the atmosphere are a very minor component They are present as water vapor, but even thought this H2O is at very low concentration, it is already the most important molecule in determination of the rate IR escapes from the Earth. That is because its IR absorption bands are much stronger than others, such as CO2. These are simple, well known facts (as certain as anything can be).

    To deny that an atmosphere which was much thicker and essentailly 100% H2O molecules would not be absolutely opaque (inpentrable) to ALL IR leaving the surface (as Venus's atmosphere is now in its hot stable state) is simply silly nonsense.

    I admit that this hot stable state of the Earth (thick scalding steam atmosphere) is would not last forever. I.e. not only will the sun eventually cease to shine, but also eventual all the ocean water will boil away into space well before the sun goes red giant. But that is such a long time into the future than we can consider the Earth with a steam atmosphere and zero surface IR escaping thru it to space to be "stable."

    In view of the above facts, can you either refute them, or offer ANY support for you assertions questioning the certainity of the existance of a hot stable state for Earth, which is caused by an atmosphere opaque to surface IR, as is the current case for Venus? Specfically, please tell if you are denying the fact that H2O is a very strong absorber of IR or are you denying the fact that surface IR which can not escape to space as it currently does would not cause a great teperature rise? (or both facts?)
     
    Last edited by a moderator: Dec 28, 2007
  23. MetaKron Registered Senior Member

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    What makes you think that Venus was ever cooler than it is now? Never mind Velikovsky. Atmospheres naturally originate from volcanoes. They come out hot. Under what circumstances would Venus have ever been cooler than it is now, being close enough to receive twice the actual heat?

    Are you denying the fact that any "scalding steam" would release a LOT of heat when it reaches the upper atmosphere? Ever gram of water that boils or evaporates takes 510 calories of heat with it. This cools the body of water that it leaves. When that gram of water chills again, it releases that heat, at a height. If anything, H2O is a great way to EXPORT heat from the Earth.
     

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