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Concentrating diesel fuel and or wood into liquid fuel?

  1. Oct 25, 2016 #1
    I was looking at btu numbers for common fuels and noticed 1 barrel of crude oil (42 gallons) contains 5,800,000 btu's with diesel fuel containing 139,000 btu's per gallon would it be possible to concentrate 42 gallons of diesel fuel to get more btu's per gallon? Also the wood into liquid fuel looking at 1 chord (957.5 gallons) of air dried wood containing 20,000,000 btu's would it be possible to convert that into a liquid fuel and concentrate it in the same manner?
  2. jcsd
  3. Oct 26, 2016 #2


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    Not really my field but as I understand it....yes...

    Crude oil continue a mix of weights or fractions that have a different energy density. These are separated at the refinery to produce tar, gasoline, diesel and jet fuel etc

    To improve the energy density of diesel you would refine it to remove some of the heavier fractions (or add some lighter fractions). This would make it more expensive.
  4. Oct 26, 2016 #3


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    Not sure about wood. I think you can ferment it into alcohol.
  5. Oct 26, 2016 #4
    What would be the best way to do that? And what kind of equipment would be needed?
  6. Oct 26, 2016 #5


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    Lighter fractions don't necessarily have higher energy density - gasoline, for example, has lower energy density than diesel, despite consisting of a significantly lighter portion of the distillate.
  7. Oct 26, 2016 #6
    Wood can be converted to methanol, an alcohol that can be, and is, used for fuel (methanol is also called 'wood alcohol').


  8. Oct 27, 2016 #7
  9. Oct 30, 2016 #8

    Randy Beikmann

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    You can potentially take one source of hydrocarbons (like crude oil), pick the most energy dense hydrocarbon, and convert it all into that. Common types of hydrocarbons are the paraffins (like methane, ethane, octane, etc.) and aromatics. This is a table showing just a few of them:


    You can see that these hydrocarbons ranges from 111,110 BTU/gallon to 130,310 (there are many more options). So you can definitely affect density by how you combine the hydrogen and carbon atoms. I don't know what the most energy-dense form is, but you could find out from a CRC Handbook.

    Whether the conversion is worth doing depends on the efficiency of the process (how much energy is consumed by doing it, for example), and the reason for making it energy-dense (compactness on a space mission would be a good reason, where cost is no object).
  10. Nov 2, 2016 #9
    Correct me if im wrong but if you have more btu/gallon an engine would have to use less fuel correct? If so im looking for the highest btu liquid fuel and energy denisity for a combustable liquid fuel and i will look in a crc handbook to look and find the highest. the cost is no issue :) edit: also what are some key words i should input to search the crc handbook?
  11. Nov 2, 2016 #10

    Randy Beikmann

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    You should end up using less fuel, if it is more energy-dense. Of course, the engine needs to be set up and sized correctly to use it most efficiently. Formula 1 teams used to formulate fuels for greatest energy density, in the 1980's I believe, to pack the most energy into the specified fuel tank volume. They even refrigerated the fuel. But they had to heat the fuel on the way to the engine so it would vaporize!

    As far as keywords to enter into a CRC handbook, mine is hard copy, so it doesn't apply for me! I'm an automotive engineer and not a fuel's specialist, but I'd start by looking up the "-anes" (methane, ethane, ... heptane, octane, ...), and "-enes" (ethylene, proplylene, etc.). Browse through the book, and you'll find many more, including isomers of the "normal" hydrocarbons.
  12. Nov 2, 2016 #11
    Hmm do you have any sources on the formula 1 formulating fuels? And also what do you think could be the highest btu per gallon? Also on the fining many more thing you said, do you mean many more fuel types and to find the isomers should i just keyword isomers of hydrocarbons?
  13. Nov 3, 2016 #12

    Randy Beikmann

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    I don't have any references on the F1 fuels, but I'm sure Google would find some. I don't really have a feel for what compound has the highest energy density - there are many hydrocarbons to choose from. I can't take you any further than that.
  14. Jan 10, 2017 #13


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    Yes, but it might be expensive, or not work well as diesel fuel. Btu per gallon is not everything.

    Diesel fuel is blended so it will ignite continuously as it is injected. The “cetane” reference standard is a mix of alpha-methyl naphthalene with a percentage of cetane. Most diesel vehicle engines specify a cetane rating of 40, which is 40% cetane with 60% alpha-methyl naphthalene.

    If the the cetane rating is below about 20 the fuel will delay ignition and the engine will make a clattering noise as fuel collects before it finally detonates. Diesel fuel can be made out of just about anything so long as it ignites like a 40 cetane reference mix. Gasoline is designed not to preignite during compression, so it makes the worst possible diesel fuel. Diesel is designed to ignite early so it is the worst possible fuel for a spark ignition engine.

    If you use diesel with a higher energy content you may need more air to burn it without producing black smoke. If you cannot boost your air induction you must wind back the maximum fuel setting on the injection pump, or let a computer do it for you.

    You can inject a gas into a diesel engine with the air. The gas does not ignite until diesel is injected and starts to burn. Methanol produced by fermentation of cellulose from wood waste can be blended into diesel fuel. You can add quite a bit of a difficult to ignite component to diesel fuel so long as it still has enough cetane equivalent to ignite.
  15. Jan 10, 2017 #14


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    @Ibexe do you not think that companies that could do this WOULD do this if it were economically advantageous? The only reasons I can think that you would believe that they would not would be (1) they just aren't smart enough or (2) it's a conspiracy to sell more inefficient product for more money. I think both of those are unlikely, so do you have a different reason for thinking it?
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