This can't end well...

Discussion in 'Off-Topic' started by joeyd999, Apr 11, 2014.

  1. joeyd999

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  2. spinnaker

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  3. Wendy

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    I saw nothing to suggest it was free energy, only that the raw materials were commonly available and dirt cheap.
     
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  4. inwo

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    I missed that to.:confused: Looks ok to me.
     
  5. THE_RB

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    Agreed. They said the CO2 and H2 were extracted at an efficiency of 92%. Obviously energy was used to extract them.

    And I'm no chemist and don't understand the process they describe but the reaction seems to use up carbonate or bicarbonate? The carbon has to be input somewhere (to make the CO2) so from my understanding their process uses energy AND carbon and the result is a liquid hydrocarbon fuel.

    I've been waiting for decades to see someone finally getting stuck into the "holy grail" of making a liquid hydrocarbon fuel (like gasoline) from energy and a cheap carbon material.

    Basically it's turning electricity into gasoline, which is a very good thing to accomplish. :)

    (Edit) Sorry I just re read it, and saw this;
    "CO2 in the air and in seawater is an abundant carbon resource, but the concentration in the ocean (100 milligrams per liter [mg/L]) is about 140 times greater than that in air, and 1/3 the concentration of CO2 from a stack gas (296 mg/L). Two to three percent of the CO2 in seawater is dissolved CO2 gas in the form of carbonic acid, one percent is carbonate, and the remaining 96 to 97 percent is bound in bicarbonate."

    So it does look like they are obtaining the carbon component from the seawater. Excellent! Energy in -> gasoline out.
     
  6. spinnaker

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    Yeah after thinking about it again, I am guessing it could really not be used for ships unless they had a nuc plant to run the process then you might as well just jun the ship on the nuc,
     
  7. panic mode

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    locally produced fuel (using nuc) could be used to power small fleet of boats, choppers etc. the bunch of vehicles don't need to have each own nuc, one on a main ship could be used to power them all (and no need for tanker)
     
  8. joeyd999

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    Sorry guys. I misread the article. As soon as I saw generating H2 from seawater (regardless of what you do with it afterword), and the word "catalytic", I assumed they were somehow producing fuel from seawater without an energy input.

    Yes, if HC fuel can be manufactured from sea water, I'll admit this is a big deal. But I assert this is *only* the case if nuclear is used on the front end for primary power generation. Obviously, burning HC's to make HC's is a waste, and wind/solar/"name your own sustainable form of power here" has not proven reliable or cost-effective.
     
  9. Wendy

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    Solar keeps improving, so don't give up on it yet. Tidal and wind are both practical and predictable next to the ocean, so it is a bit premature to declare nuclear as the only option. I never liked birds anyhow. :p
     
  10. Brownout

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    Indeed! I used to hear all the same things said about cellphones, now everyone I know uses one.
     
  11. Evil Lurker

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    Ok so there is a 100mg of CO2 per liter of seawater. Ignoring my chemistry, I'm thinking that would roughly equate to 30mg of carbon per liter. Now then a liter of gasoline contains roughly ~650 grams or so of carbon bound to a hydrogen skeleton. Considering it takes 23+ liters of seawater to extract a gram of carbon and roughly multiply that number by 650 and your looking at processing 21,000+ liters of seawater just to make a liter of jet fuel.

    Don't sell your Exxon Mobil stock just yet...
     
  12. Brownout

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    And so what? There's a gizzilion liters of seawater, and the processing doesn't use it up, so it's an infinite resource. It just absorbs more carbon.
     
  13. nsaspook

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    The whole point is to provide JP5 type fuels for nuc carriers without the long logistics train of tankers following the fleet. The possible end-to-end efficiency (pumping water,etc...) and suitability for energy storage ($3-6/gallon is compete hype when actual plants costs are used) is not really discussed in the article because the objective is fleet independence not energy efficiency. I can see how it would be useful if you already have power source with excess power idling but having a refining plant inside a already packed ship, using tens of megawatts of electrical energy to generate volatile pumped ethylene, propylene, and butylene (with methane byproducts) compounds as the base carbons for the (relatively safe) complex fuel hydrocarbons might be a risk because fuel fires were the #1 thing we trained on in Navy fire fighting school. Heavy fuel fires are dangerous but manageable because there is rarely an explosion from the fuel itself but the primary catalyst products here are easy to react and oxidize back to CO2 and water.
    http://hydrocarbonsalkanealkene4p104.blogspot.com/p/properties-of-alkanes.html

    Navy background document for this research.
    http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA539765
     
    Last edited: Apr 12, 2014
  14. GM11

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    Removing Carbonic acid by removing the Carbon is a good thing, takng carbon from carbonate or bicarbonate in saltwater is not a good thing.
    So depends how they do it, it is far easier to remove carbonic acid and the sea's are acidifying which is bad. The easiest way to remove carbonic acid is to simply bubble air into it! you only get around 14% however this way.
    There is also talk of carbon storage in old gas wells. The plan is to take carbon dioxide from the air compress it and store as a liquid. I would rather see this carbon used for fuel.
     
  15. Wendy

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