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Synthetic Fuel

  1. Oct 23, 2005 #1
    From a layman point of view:

    What is the main problem for producing sinthetically (and at reasonable costs) fuel for internal combustion engines?
    When we hear about the running out of fossil fuels, we are always drawn to the alternative energies (hydrogen fuel cells, electric cars etc), but we never hear about the possibility to produce the fuel artificially.
    Being such a multibillion industry, one feels that if there would be even the most remote possibility of success, corporations would be surely already investing millions in researching such a possibility, so something must be really wrong to disencourage such research.
     
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  3. Oct 23, 2005 #2

    Pengwuino

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    From what I've heard around here, there is your problem. Plus if we can get hydrogen down to a reasonable price (which i assume they'll be able to since cost is never brought up as a problem), why would we need to synthesize more gasoline?
     
  4. Oct 23, 2005 #3

    Q_Goest

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    Alchohol is an 'alternative fuel' but it costs much more than gasoline and has only half the energy capacity. Then there's the issue of trying to manufacture enough to replace petroleum. The amount of biological hydrogen we'd need to grow is huge and I suspect it would be impossible to grow that much hydrogen.

    Another alternative fuel is synthetic petroleum made from biodegradable garbage. A prototype plant was built that took the waste from a turkey slaughter house and converted it to oil. I understand it was quite successful. But even if we converted all of our garbage to oil in this way, we'd fall short by a long shot in trying to replace petroleum. Believe it or not we simply don't make enough garbage for this to work! lol

    Perhaps one of the most problematic issues regarding alternative fuels is that they will invariably contain carbon which when burned, results in carbon dioxide. We can't keep pumping CO2 into the atmosophere because of the huge climate changes that are taking place even today.

    Hydrogen isn't a shoe in either. There are tremendous issues in using H2, namely:

    1) Storage - If stored as a cryogenic liquid it will invariably boil off and vent. If the vehicle is inside a garage or other enclosure, you risk filling it with an explosive mixture, so cryogenic storage has largely been dismissed. Another alternative is compressed H2, the problem there being the safety of people trying to use the dispensing equipment. So far there have been no accidents that have shut down this as a possibility, but if you put enough 10,000 psi dispensers in the hands of the public, the potential for catastrophic accidents is much higher than the gasoline. This includes the problems of storage on the vehicle and potential accidents during collision. The only good way of storing would be using hydrides based on metals or carbon. The most promissing one I've seen regards a "reversible liquid hydride" proposed by Guido Pez et al (Air Products and Chemicals, Inc). Here, the hydride would actually be recycled - you'd fill one tank on your vehicle with a special liquid hydrocarbon (decalin -> C10H18 <numbers are supposed to be subscripts>) and convert it by heating to napthalene (C10H8) + hydrogen (5H2). The hydrogen is taken to a fuel cell while the napthalene is returned to a second fuel tank (essentially the same tank separated by a diaphragm) for recycling. When refueling, you have 2 hose connections, one to remove the napthalene and the other to load the dacalin. From what I've gathered, the big oil companies aren't too happy with this one yet. Though I don't know why for sure it certainly has a lot to do with profits. Perhaps when petroleum is finally forced to stop flowing, big oil will embrace it. You can read more about it on this presentation at page 15 on down.
    2) Production - Most hydrogen is presently produced from natural gas. There are many ways of producing it in other ways such as electrolysis, bacteria which produce it organically, etc… Presently, the production of hydrogen from natural gas or petroleum is by far the least expensive.
    3) Infrastructure - There isn't one… This is no small issue. What form of hydrogen is used will dictate what the infrastructure looks like but so far hydrogen gas is the only method being taken seriously and that just isn't going to work.

    <that's enough writing for 1 day>
     
  5. Oct 24, 2005 #4
    You have numbers on that?

    This would be true if we weren't taking the CO2 out of the air at the same rate as it's being put in; which is what would happen. If we use alcohol, synthetic petroleum, ethanol etc., guess where that CO2 is coming from? The air. We'll increase CO2 no more than using wood as fuel while simultaneously planting a tree, or more, to replace the slain autotroph.
     
  6. Oct 24, 2005 #5

    Q_Goest

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    Hey Skeptic. I did some rough calcs on how much garbage we'd need. It comes out to about 3 times the amount we presently use, though we certainly could reduce the amount of energy we consume which may bring the amount of energy produced from garbage closer to the amount of energy we could create from it. That's a bit more detailed than I was needing to calculate though as it requires some assumptions regarding how much garbage would be reduced given a reduction in energy.

    Regarding CO2, I don't have anything on that. If all the CO2 that goes into garbage comes from the air (ie: from plants absorbing CO2, eaten by animals, etc...) then that would be terrific. I'd be interested in what that chain looks like though I suspect it needs significant research to do the job right. I've not given it enough thought to know for sure if that's a slam dunk or needs detailed research.
     
  7. Oct 24, 2005 #6
  8. Oct 25, 2005 #7
  9. Oct 26, 2005 #8
    What were, simply speaking, the chemical processes by which Nature produced petroleum from the raw materials available on planet Earth?

    Is it conceivable to reproduce the same chemical processes, but applying catalyzers so that the process for which Nature took thousands of years could take days in a lab?
     
  10. Oct 26, 2005 #9
    Do an advanced search for username <hitssquad>, text <nuclear gasoline>, and restrict to <posts>.
     
  11. Oct 26, 2005 #10
    I would also like to see more information / numbers on this topic. If it works well, why couldn't we employ the process to help our increasing garbage problem and reduce our dependance on foreign oil and natural oil alltogether. Even if it cannot completely replace natural oil I would think it could stretch the use of the natural oil that is still left. If the process really was that successful, even if it couldnt completely replace our current oil, I think it would solve a lot of problems.
     
  12. Oct 26, 2005 #11

    Pengwuino

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    Why bother with making more fuel. Go team hydrogen!
     
  13. Oct 26, 2005 #12
    Well hydrogen fuel isn't perfected yet, while our system of oil and gas pretty much is. I agree that hydrogen is probably the direction of the future, but why not prolong the life of oil while were perfecting hydrogen?
     
  14. Oct 26, 2005 #13

    Pengwuino

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    Well we arent exactly sure how to synthesize it effectively though so its not a perfect system at all. Plus why put more crap into the air.
     
  15. Oct 26, 2005 #14
    Well obviously our use of the fuel isn't perfect, it never will be. I'm talking in terms of storage, distrubution etc. When is the last time you saw a hydrogen filling station? Even if the technology was ready today, we would still need to create all of the infastructure to handle the new fuel. Every aspect hydrogen power needs to be researched further before we can start to implement it as a practical replacement to petrolium. I don't think any of the new technologies will be fully ready in time, so why not try to prolong the life of our current fuel?
     
  16. Oct 26, 2005 #15

    Pengwuino

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    What does "in time" mean?
     
  17. Oct 26, 2005 #16
    Before we either run out of crude or until the point where it gets so expensive because of the supply demand situation that it becomes too expensive to be sensible.
     
  18. Oct 27, 2005 #17
    Because it's not just about the fuel, we have to have hydrocarbons, for now, to create non-biodegradable plastics, tires, paved roads etc. Also hydrocarbons hold massive amounts of energy per volume. Try pushing your car or SUV to work to see what I mean. Oil really is "black blood".
     
  19. Oct 27, 2005 #18
    What types of garbage/organic mass did you factor? Remember, an input has to come from the sun. You can't use only plastics forever, because of entropy. There must be an outside energy source such as the organic matter. Or solar collecting mirrors/PV/geothermal etc. could power the plants, for even greater oil production without spending some of it's own oil production to fuel itself.
    Did you account for:

    Human feces, still holds energy from the sun we didn't get.

    Cow feces, ditto.

    Pig feces, ditto

    grass

    dead trees

    Life grown for their biomass to be converted into oil. Water hyacinths, algae, bamboo and kudzu come to mind.
     
  20. Oct 27, 2005 #19

    Q_Goest

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    Some information on what type of garbage was expected to be used was presented on another web page somewhere, way back when. It seemed to indicate just typical garbage, though I'd agree with you that there are many other sources of 'garbage' that we might include. I compared data available on garbage produced by an average person in the US, not what other sources might be employed. It's not hard to rough out a calculation to determine how much waste is needed to produce the energy. One other consideration though is that the byproducts of this plant are not JUST oil, they include many other things, some of which are also useful.

    Doing a very rough calculation like this is easy enough, I'm sure you could do that in a matter of an hour or two, that's about all I spent on it. I'm sure there are some very authoritative studies done on this process. It would be interesting if someone took the time to research it further and post some findings. <hint - hint> :wink:
     
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