Name your favourite BioFuel Technology

Discussion in 'Earth Science' started by Singularity, Feb 20, 2006.

  1. 2inquisitive The Devil is in the details Registered Senior Member

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    I agree hydrogen is not the way to go, but I am interested in your implication that biodiesel has toxic byproducts. Most biodiesel that is currently sold commercially is a blend of petroleum and biodiesel, such as B20, but it is entirely unnessary for biodiesel fuel to contain petroleum products. Straight biodiesel is biodegradable and non-toxic. You can drink it without harm. Most diesel engines can run fine on it WITHOUT MODIFICATION to the engine. My 'second vehicle' is a Dodge pickup with a Cummins turbodiesel. The retired Math professor that owned the truck before me ran it on home-brewed biodiesel for years with no harm to the engine. The 'polution' of these older diesels is mostly in the form of particulate matter when using vegetable oil based fuel. New technology, such as Daimler-Chrysler's Bluetec technology, includes particulate filters to result in clean diesel engines that give much better fuel milage than gasoline or alcohol engines. The diesel engines also last much longer. The drawback is they are much more expensive to manufacture.

    My prediction for the future is for both biodiesel and alcohol based vehicles to become much more prevalent. Electricity production should shift to more use of tidal-based generators, wind-based generators and nuclear-based generators to ease the supply and demand placed on vegetable-based fuels. Yes, I am aware all these have their enviromental impacts, but I know of no 'free-lunch'.
     
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  3. Carcano Valued Senior Member

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    I wouldn't drink it...its made with methanol isn't it? Even tiny amounts of methanol ingested can cause blindness.

    As far as the emissions of pure 100% biodiesel are concerned, its much worst than pure ethanol, which has no emissions other than water vapour and CO2.

    Biodiesel Emissions:
    Unburned Hydrocarbons 67% less than diesel
    Carbon Monoxide 48% less than diesel
    Particulate matter 47% less than diesel
    Nitrogen oxides 10% more than diesel
     
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  5. 2inquisitive The Devil is in the details Registered Senior Member

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    No, biodiesel does not HAVE to use methanol. It can also use ethanol. Pure peanut oil can also be easly be used in a diesel engine for fuel. The professor I spoke of used recycled french-fry oil.

    You will have to qualify your statement that ethanol 'has no emissions other than water vapour and Carbon dioxide'. That only happens when the combustion is 100% efficient. Engines are not 100% efficient in burning ethanol, carbon monoxide and other compounds such as nitrogen oxides are produced. Diesel engines are much more efficient than gasoline or ethanol engines, and carbon monoxide from a diesel engine is much less than produced by gasoline engines even when burning fossile diesel. The particulate matter produced is much lower when burning biodiesel, and is reduced much more with the particulate filters I mentioned earlier. Newer technology diesel engines are VERY CLEAN, very efficient, and can be improved much more if pure biodiesel becomes widely available. Pure biodiesel IS completely vegetable based, just as alcohol, and contains no more 'toxins' than alcohol.
     
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  7. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I may be mistaken, but I think "pure peanut oil" was exactly what the world's first diesel, invented by Otto Diesel as I recall,* ran on.
    I too am a big fan of biodiesel. It is rapidly expanding in Brazil, but for reasons I do not understand, diesel cars are illegal in Brazil. (Probably has to do with expanding the domestic market for regular IC engine cars to help local car makers concentrate their efforts.)

    There is weed, it makes a seed that looks very much like the balls that a sycamore tree makes. It grows wild all over Brazil. Now this weed is a cultivated crop in rapidly expanding plantations because it yields much more oil than most any other plant/per acre. It is called "mammon" or something phonetically like that. In five years or so, Brazil will be exporting biodiesel as it is now alcohol. It certainly requires zero fertilizer - until recently it was a plague, growing in your pasture, and still is, if you are raising beef.
    ------------------------------------
    * No I did not know him personnally - I am not THAT old.

    PS how often do those filters need to be changed?
     
  8. 2inquisitive The Devil is in the details Registered Senior Member

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    Correct, Billy T, pure peanut oil was used in the engine invented by Rudolph Diesel. His engine was designed to run on peanut oil OR petrodiesel, whichever was locally available.

    Diesel engine run fine on several pure vegetable oils, also tallow (beef fat), but pure oils tend to produce engine deposits and choked injector nozzles over time. Esters of oils and fats eliminates those problems. Esters of oils can be produced by adding methyl or ethyl alcohol along with a catalyst, usually sodium hydroxide, to a vat of vegetable oil and letting the esters of oil settle out. The process causes two layers, esters on top and Glycerin on the bottom. The Glycerin has market potential of its own, it makes good degreasers and hand soap, for example. To make home-brewed biodiesel, the glycerin is drained off and the remaining ester of oil is filtered.

    The biggest problem to overcome for biodiesel is that it thickens (gels) more than petrodiesel at low tempratures. That problem is being addressed by the industry, but I am not aware of a really good solution as of now.

    Billy T, I don't know what the servace interval of the Particulate filters used in DaimlerChrysler's Bluetech engines are. I read of the technology in a magazine and service intervals was not mentioned. Jeep is currently testing a Grand Cherokee (SUV) with a Mercedes-Benz Bluetech V-6, but it is a fairly expensive. It is a four-valve double overhead cam design. The vehicle is said to be production ready, probably to be introduced in the 2007 model year.

    As I stated earlier, I believe there is a market for BOTH alcohol and biodiesel vehicles. The choice between the two engines could depend on their purpose and buyer resources (money). One advantage of diesel engines is that they can burn either biodiesel or petrodiesel without modification and diesel milage per gallon of fuel is higher than gasoline engines. Alcohol milage per gallon of fuel is less than with gasoline. But the diesel engine is more expensive to manufacture, resulting in higher initial cost.
     
  9. Carcano Valued Senior Member

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    6,865
    Ethanol is very rarely used to make biodiesel for two reasons:

    1. It is a much larger molecule than methanol and requires longer reaction times and higher temperatures during processing.
    2. Ethanol is also more difficult to recycle due to its azeotrope with water in a 95% concentration.

    So, why is all this processing with toxic chemicals like methanol and sodium hydroxide (caustic soda) neccessary - because diesel engines don't run well on pure vegetable oil unless the fuel tank is heated, otherwise the oil is too thick and viscous to flow and ignite well in the engine.

    I have heard of people using mineral spirits, as well as one or two other nasty chemicals, to thin it down - apparently this was a technique used in Europe during WWII, when diesel fuel was rationed.
     
  10. spidergoat pubic diorama Valued Senior Member

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    The only thing biodiesel may prevent is dependence on middle east oil supplies. It won't end global warming, and production of biofuels is still dependent on having cheap petroleum. We are totally screwed.
     
  11. 2inquisitive The Devil is in the details Registered Senior Member

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    3,181
    First point. Ethanol biodiesel can be home-brewed at room temperatures. Home brewing with ethanol is more tricky than with methanol. Potassium hydroxide can be used instead of lye so processing times are about equal, about 6-8 hours. How long does it take to ferment grain to make ethanol?
    Commercial processing of ethanol biodiesel should be a relatively simple operation, if it can be done at home.

    Yes, methanol is classified as a toxic chemical. It is wood alcohol. You do realize that all ethanol used in 'gasahol' blends comes from processed gasoline, not grain alcahol don't you? It is cheaper to get the 199 proof ethanol from petroleum than it is with grain.

    I already mentioned why esters of oil was preferred over pure vegetable oil. And yes, diesel engines do run fine on pure vegetable oil without 'heating the fuel tank' EXCEPT in cold temperatures, like near freezing. Again, engine deposits over time and gelling at cold temperatures are the main drawbacks of pure oil.

    Here is a chart that might interest you:

    "The concept of "input efficiencies for fossil energy sources" was introduced as a component of the study. This was meant to account for the fossil energy used to extract, transport and manufacture the raw material (crude oil) into the final energy product (gasoline). According to the study, gasoline has an energy ratio of 0.805. In other words, for every unit of energy dedicated to the production of gasoline there is a 19.5 percent energy loss.

    In summary, the finished liquid fuel energy yield for fossil fuel dedicated to the production of ethanol is 1.34 but only 0.74 for gasoline. In other words the energy yield of ethanol is (1.34/0.74) or 81 percent greater than the comparable yield for gasoline.

    Bio-Diesel versus Petroleum Diesel
    A similar study was co-sponsored by the United States Department of Energy and the USDA, entitled, "Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban Bus."

    The study, published in May 1998, states; "Biodiesel yields 3.2 units of fuel product energy for every unit of fossil energy consumed in its life cycle." The report continues, "By contrast, Petroleum diesel's life cycle yields only 0.83 units of fuel energy per unit of fossil energy consumed." According to this analysis, the energy yield of biodiesel is (3.2/0.83) 280 percent greater than petroleum diesel fuel.

    Summary - Energy Balance/Energy Life Cycle Inventory
    Fuel * Energy yield Net Energy (loss) or gain
    Gasoline 0.805 (19.5 percent)
    Diesel 0.843 (15.7 percent)
    Ethanol 1.34 34 percent
    Biodiesel 3.20 220 percent

    * Life cycle yield in liquid fuel Btus for each Btu of fossil fuel energy consumed.

    The positive energy ratio displayed by ethanol and biodiesel is accounted for by the contribution of solar energy collected by the crop from which the fuel is made. This energy is considered "renewable" because a new crop is raised each year.
    http://www.mda.state.mn.us/ethanol/balance.html
     
  12. Carcano Valued Senior Member

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    6,865
    Part of the process involves removing as much of the excess methanol as possible by distillation at its boiling point - far above room temperature. The reactive part of the process uses boiling point temperatures as well, to speed it up.

    Processed biodiesel starts to gel at +5 degrees celcius - raw vegetable oil is even worse. You can test this yourself simply by putting a jar of peanut oil in the fridge, which maintains a cool temp well above zero. It will turn into a cloudy jelly-like substance in just a few hours.
     
    Last edited: Mar 31, 2006
  13. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    23,198
    Speaking about "closed minded"
    Did you see 2inqusitives's post taken from Minnesota Dept. Agriculture report partially quoted below? Some how I do not think Minnesota is the area you were thinking of in your text I made bold above.

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    See report at:

    http://www.mda.state.mn.us/ethanol/balance.html

    where it states:

    "Biodiesel yields 3.2 units of fuel product energy for every unit of fossil energy consumed in its life cycle." The report continues, "By contrast, Petroleum diesel's life cycle yields only 0.83 units of fuel energy per unit of fossil energy consumed."

    That is Biodiesel yields are almost 4 times better than petroleum diesel!!!!!!!!!

    Also from report:
    "The positive energy ratio displayed by ethanol and biodiesel is accounted for by the contribution of solar energy collected by the crop from which the fuel is made."** I might add: Fact that only part of the crop becomes fuel but all the carbon in crop is taken from the air means that using bioFuels in your car not only make city air cleaner, but also REDUCES "global warming" by CO2 !!!!!! Get on the band wagon, before it runs over you. OR - If you can "lick em", "join em." Don't let the oil compnaies sell you a lot of "Hydrogen Talk." - They are promoting H2 as it has no chance of competing with oil, but biofuels, which are made by nature's economical, self-reproducing, factories, we call plants, and solar energy, cheaply collected by green plants, can destroy the oil industry. (Lets feed the world, not fight it for oil.)

    Summary - Energy Balance in Energy Life Cycle*

    Gasoline 0.805 = 19.5 percent net energy loss
    Diesel 0.843 = 15.7 percent net energy loss
    Ethanol 1.34 = 34 percent net energy gain
    Biodiesel 3.20 = 220 percent net energy gain**
    ----------------------------------------------
    * Life cycle yield in liquid fuel Btus for each Btu of fossil fuel energy consumed.

    **You are partially correct in that in Brazil there is also more human energy input than in Minnesota (or US in general) so biodiesel and alcohol numbers will be higher for Brazil's production. I do not have hard data, but think that alcohol produced from cane in Brazil has energy balance of about 2. - A net percent energy gain three times bettter than the 34% given above!

    Once Brazil's "mamon weed" is main feed stock for biodiesel, I bet the Energy balance of biodiesel goes well above 5, perhaps above 6, not this study's 3.20. (Mamon is common weed in Brazil, but now being raised as crop on new plantations in the NE of Brazil. That weed has much higher oil content than any other plant known. The oil comes from a seed pod that looks like the ball made by a sycamore tree, but is green. These balls are all over the bush like plant.)
     
    Last edited by a moderator: Mar 31, 2006
  14. Carcano Valued Senior Member

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    6,865
    Ultimately, in terms of what fuel is best all around, I think it comes down to only two factors:

    1. Emission levels.
    2. The actual cost of driving in terms of 'cents per mile'.
     
  15. Singularity Banned Banned

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    1,287
    3. Are the output pollutants Less/More than what the plants absorb in growth of the fuel.
     
  16. 2inquisitive The Devil is in the details Registered Senior Member

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    3,181
    Carcano, I specifically said I was speaking of 'home-brewing' biodiesel. No boiling is required, only a coil circulating hot water through the mixture. The process is actually pretty simple, the reason I said it should not be a problem to produce commercially. Of course, commercial processes will be more refined and different. Here is a cut & paste from a site that sells equipment for home use and much info on biodiesel in general. Much of your info seems dated. Biodiesel has suffered the ire of the oil industry in the past and was discouraged, for obvious reasons. Read some of the newer papers at this site:

    "How is Biodiesel made?
    It's a very simple process. Vegetable oil is placed in a reaction vessel where an alcohol and a catalyst is mixed into it. After mixing for a period of time, the mixture is allowed to settle. The mixture will separate and form two distinct layers. The top layer is Biodiesel and the bottom layer is the glycerol. After sufficient time has passed to allow complete separation, the glycerol is drained out and the remaining Biodiesel is washed to remove excess catalyst and other impurities before finally being filtered for use.


    How long does it take to make a batch?
    Our Processors are designed to make one batch, from start to finish in a matter of 6-8 hours. In general, consider it one batch in one day.

    How much does one gallon cost to make with your equipment?
    In most cases you can make top quality biodiesel for US $0.50 to US $0.90 per gallon, all manufacturing costs factored in.

    Are there any dangers?
    Yes. As with any chemical process, there are some dangers. If Methanol is used, exposure to it can cause blindness and eventually death. The catalyst is highly caustic and will cause severe burns. But if you follow the precautions, and you use quality constructed equipment, you should never come in contact with these chemicals.

    Where do I get the equipment to make Biodiesel?
    Until now, you had to make your own processor. Now you can buy processors. If you are handy with power and hand tools and understand the principals involved, you can build your own quite easily. If you don't have the "know how" or the time to build one of your own, you can now pick from a variety of models or have us custom build one for you. Just because you can't build one doesn't mean you can't make and use Biodiesel. Any of our models will barely add $0.10/gal to the cost of your Biodiesel

    Where do I get the supplies I need for the process?
    Supplies are not difficult to get. Methanol can be purchased from most automobile race shops, educational or lab supply houses. The catalyst (Sodium Hydroxide) is available in quantity from the larger janitorial and cleaning supply houses. For small quantities, Heet or Drigas brand fuel line antifreeze is pure Methanol and Red Devil drain cleaner (Lye) is Sodium Hydroxide.

    Where do I get the oil to make my Biodiesel from?
    Biodiesel can be made from fresh oil or used restaurant oil."
    http://www.biodieselgear.com/documentation/index.htm

    P.S. Billy T, you may get a kick out of the name of the webhosting company at this site: DarkStar IV.
     
  17. 2inquisitive The Devil is in the details Registered Senior Member

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    3,181
    by Carcano:

    "Processed biodiesel starts to gel at +5 degrees celcius - raw vegetable oil is even worse. You can test this yourself simply by putting a jar of peanut oil in the fridge, which maintains a cool temp well above zero. It will turn into a cloudy jelly-like substance in just a few hours."
    ================================================================

    Do you work for the oil industry? Your numbers are skewed. I live in the south and I specifically stated that peanut oil could be burned in WARM WEATHER. I personally know of it being done. A friend of mine witnessed a friend of his (yes, I know, but it is still the truth) buy two 5 gallon jugs of peanut oil in Wal-Mart and pour it directly into his fuel tank (Cummins engine). Usually some diesel fuel supplements are added, but not necessary for an emergency or one-time event. Peanut oil has a cloud point of 12.8C. That is the temperature when the wax in the oil makes the peanut oil cloudy. It has a 'pour point' of -6.7C. That is the point the oil begins to gell. Pure peanut oil has a cetane rating of 41.8. Cummins recommends a cetane of 42, but anything from 40-50 is acceptable. Again, I am not recommending pure vegetable oils as diesel fuel, only stating they can be used for short time periods in an emergency situation.

    Biodiesel from esters of rapeseed oil, for example, has a cloud point of -7C and a pour point of -16C, far from your 'starts to gel at +5 degrees celcius'. This is with no additives to lower the numbers. I did not 'pick' rapeseed oil because it was lower than other esters, it was just the first paper where I found numbers. I knew your +5 degrees number was nonsense, but needed a example. Where are your links? Here is the one to rapeseed esters from Univ. of Idaho:
    http://www.biodieselgear.com/documentation/University_of_Idaho_Biodiesel.pdf
     
  18. Carcano Valued Senior Member

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    6,865
    http://www.elements.nb.ca/theme/renewable_energy/wayne/groszko.htm
    But even if I posted a hundred links, thats still not as good as buying a bottle of peanut oil and putting it in your fridge, so you can see for yourself. Try it!

    Notice also in the above link that biodiesel actually produces MORE smog-forming nitrogen oxide emissions than petroleum diesel - not good.
     
  19. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    23,198
    Some more/some less. It depends upon what you are concerned about:

    For example, Alcohol fuel for your car produced from growing cane, with modest if any input of fertilizer definitely removes CO2 for world's air; however, if your car has an IC engine, (and 99.999999+% do), as constrasted with an external compustion engine (Such as a Sterling engine) or a "chemical reformer" which could convert the ethonal into H2 for fuel cell, then you can be sure that even alcohol is adding to the NOx pollution of your city.
     
  20. 2inquisitive The Devil is in the details Registered Senior Member

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    3,181
    Carcano, what is the temperature inside your 'fridge'? Mine is near the freezing point, vegetables and sometimes milk will form ice crystals. Is your point that one cannot use pure vegetable oil in cold climates, like wintertime in Canada? So what?

    I thought you might have an ulterior motive for dismissing biodiesel as an alternate fuel source. I now think it is just due to ignorance. Here are the other facts from YOUR link:
    B100 biodiesel vs. petroleum
    CO -43.2% less
    Hydrocarbons -56.3%
    Particulates -55.4%
    Air toxics -60% to -90%
    Mutagenicity -80% to -90%

    That is why I said you 'skewed' the figures. You most definately do, either from bias or ignorance. New technology, such as the particulate filter I already mentioned, reduce the pollutants even farther. Understand?
     
  21. Carcano Valued Senior Member

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    6,865
    No, all of north america, excluding maybe the southern tip of Florida, Texas. On a winter day the temperature can get down to the point where pure vegetable oil will thicken enough to stop a diesel engine, as explained here:
    http://www.brevardbiodiesel.org/vegoil.html
    Take note that hes is talking here primarily about processed biodiesel, not pure vegetable oil, which is even worse.
     
  22. Carcano Valued Senior Member

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    Yes, I posted some of those figures myself a few pages back. Its an improvement on diesel fuel, but biodiesel still produces MORE smog-forming nitrogen oxides than petroleum diesel.
     
  23. 2inquisitive The Devil is in the details Registered Senior Member

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    Have you ever heard of a catalytic converter, Carcano?
     

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