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Oil from genetically-modified organisms

  1. Jun 19, 2008 #1

    turbo

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    A Silicon Valley startup "LS9" is genetically modifying E.coli and yeast to excrete a petroleum substitute instead of the fatty acids they would normally produce during fermentation. The great thing about this is that they can be fed practically any type of organic waste, and the process need have no impact on food supplies. It will be interesting to see if they can scale up the process so that it's commercially viable.

    http://www.timesonline.co.uk/tol/news/environment/article4133668.ece
     
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  3. Jun 19, 2008 #2

    Kurdt

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    I wonder if it could be modified so you could feed your car all your organic waste with some system containing the bacteria that would cut down on transporting the fuel. That is of course probably looking too far ahead.
     
  4. Jun 19, 2008 #3
    You mean so I could take a crap right into my car?
     
  5. Jun 19, 2008 #4

    Kurdt

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    I meant like vegetable peel and things like that :rolleyes: Like I say I'm probably being over enthusiastic though.
     
  6. Jun 19, 2008 #5

    Astronuc

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    Apparently gasoline is so expensive in Gaza (~$27/gal), that taxi drivers are fueling with just about anything organic, e.g. cooking oil + kerosene, pesticides, deoderizer, . . . . That has prompted an increase in the price of cooking oil.
     
  7. Jun 19, 2008 #6

    mgb_phys

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    I'm sticking with crude oil. At least it's organic - it was definately grown without any man made chemicals or pesticides. Coal is even better, it's vegan!
     
  8. Jun 19, 2008 #7

    turbo

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    As with any fermentation process, there is a time factor to be considered, and you have to maintain optimal living conditions for the bugs, and then there's the separation, extraction, and refining of the oils. My license has lapsed, but while I was a process chemist, I was responsible for overseeing the operation of the mill's wastewater treatment plant. It was a juggling act keeping conditions right so that the bugs would do their work - pH, temperature, dissolved Oxygen levels, bug population density and type... I imagine that these fellows have to learn to control all these things, too.
     
  9. Jun 19, 2008 #8

    Kurdt

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    Yeah, I was just thinking out loud as usual.
     
  10. Jun 19, 2008 #9

    turbo

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    It would be nice to have some kind of enzyme that would break down organic waste VERY quickly, but that's probably pie-in-the-sky, too. Anything that powerful would be dangerous for humans to come in contact with.
     
  11. Jun 19, 2008 #10
    I've been in a few cars where it smelled like someone took a crap. :rofl:
     
  12. Jun 19, 2008 #11

    mgb_phys

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    If you don't mind the smell there is a readily available multi-chamber production system that converts plant matter to methane at around 700 litres/day. At 900 KJ/mol thats only about about 26MJ/day, (less than a gallon of gasoline) but for short commuting trips my new system could work.

    Converting your pickup to run on natural gas is already fairly easy ( there are many cars in europe converted to lpg) then all you need to do is put a bale of hay in the back, add the cow and insert the pipe (diagram provided).
     
  13. Jun 19, 2008 #12

    turbo

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    :rofl: That system is noisy and emits corrosive liquid by-products that will rot the bed of your pickup in no time flat.
     
  14. Jun 19, 2008 #13

    mgb_phys

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    Ok so it's not going to be very popular in convertibles, unless you like having a cows tongue wiped across the back of your neck. Compact cars would probably have trailers or need to use little baby calfs.

    But picture it, a line of gently mooing Holstein's double parked outside the school in the morning instead of minivans.
     
  15. Jun 19, 2008 #14

    turbo

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    Mooing and farting...
     
  16. Jun 19, 2008 #15

    DaveC426913

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    Actually, not to be too much of a buzz-kill, but IIRC the majority of methane comes from the prettier end of the cow.
     
  17. Jun 19, 2008 #16

    Ivan Seeking

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    There is a similar result obtained using algae, and this is what seems to be the question: Is it more efficient to collect and process biomass, than it is to grow algae using sunlight? [I realize this isn't about algae, but the same question applies.]

    Microalgae are likely far more efficient at converting Cs, Hs, and Os, to a fatty acid or sugar, using sunlight, than are any large plants. The conversion efficiency of algae is thought to range from 1%, to a theoretical limit of something like 10%, for fatty acid [vegetable oil] production, based on the incident solar flux. And, microalgae effectively use 100% of the land or water area required.

    So how much land does it require to provide the needed biomass in terms of the gross gallons of fuel produced per acre-year of biomass? Do we have enough land?

    Then we have the extra step of converting from biomass to food for the bacteria. So we spend energy here.

    Next, algae can be recovered using water flow in closed systems, whereas biomass must be collected and transported with machines that need energy.

    Then we would have to consider the processing efficiencies at the point of entry to the fuel processing plant. So, how much energy is spent collecting the biomass? How much efficiency is lost through the added step of convering biomass to something usable by the bacteria? And how do the process efficiencies compare beyond that point?

    It seems to me that the viability of this approach needs to be considered first, in principle, rather than in practical terms.

    Just shooting from the hip, the simpler direct conversion from sunlight, water, NPK, and algae, to fatty acids or sugars, would probably be more efficient. But, for algae, there is the NPK. The nitrogen supply is always an issue. And algae will require bioreactors, so there is a high start-up cost per square foot of sunlight [nothing like the cost of solar panels, however]. There are also materials used that require energy to make. And they have a finite lifespan.

    Note: when considering efficiencies, plants select certain ranges of frequencies - the photosynthetically active radiation - so when we compare the efficiencies of plants or solar panels, the active flux has to be compared to the incident flux, in addition to the efficiency of the active radiation.
     
    Last edited: Jun 19, 2008
  18. Jun 19, 2008 #17

    turbo

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    For sure, any new energy technology will get an early buzz, and I detect quite a bit of cheerleading in the original article, but I have hopes. All around the country, there are agricultural by-products, municipal wastes, and other streams of organics that can feed algae, bacteria, and yeasts. How can we tap these nutrient streams and end up with concentrated, portable energy sources. That's the big one. Who can get beyond theory, proof-of-concept, pilot plants, and manage scale-up headaches to get to commercial viability?
     
  19. Jun 19, 2008 #18

    Ivan Seeking

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    The trouble is the hidden energy costs, such as the coal power and diesel used to make ethanol. Due to the market structure, these costs remain hidden.

    I don't remember the exact numbers, but it can be shown that that [for example] for every three gallons of gasoline that would be sold, we now buy 4.6 gallons of ethanol, and still use an additional two gallons worth of diesel, or energy from other sources, to make the ethanol. This is easy to show, and many argue that it takes at least 3 gallons of gas [in energy] to make 4.6 gallons of ethanol, but we are still buying ethanol.

    Also, any approach must be shown to be capable of scale. That it would take more land for corn than we have land in the entire US, to replace gasoline with ethanol, is not apparent at the pump - we are still buying ethanol.
     
    Last edited: Jun 20, 2008
  20. Jun 19, 2008 #19

    turbo

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    When I was a training consultant, I surveyed a project at Quantum Chemical in Iowa. They had a little plant located in the middle of farm country, and with my background in chemistry and engineering, I could see from the first visit that they were living on subsidies and could never produce ethanol and other hydrocarbons on a commercially-viable scale in a thousand years. Most alternative energy projects are boondoggles designed to separate money from taxpayers.
     
  21. Jun 20, 2008 #20

    Ouabache

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    Sounds a lot like trying to make tofu taste like meat (making an oil substitute). I sincerely feel time would be better spent generating energy from alternative sources (tidal, geothermal, solar, wind...), convert to electricity and use that to power our energy hungry global community.
     
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