methane gas as a fuel?!?!

Discussion in 'Homesteading Questions' started by Ariel, Nov 12, 2004.

  1. Ariel

    Ariel Active Member

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    In Back to basics, there is a page on setting up a poop composter to make methane gas. It looks dangerous.

    Is anyone doing this? If so, tell us all about it.
     
  2. agmantoo

    agmantoo agmantoo Supporter

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    I have not seen the article but I have seen (in India) a methane generator setup to provide cooking gas. I did not view the gas to be dangerous as the pressure is very low and on the plus side the system was super simple. The drawback, particularly in other than summer months, in many parts of the US and Canada would be the cooler/colder temperature. Heat is necessary to start the process.
     

  3. sylvar

    sylvar Well-Known Member

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    I saw one once a dairy barn. All the poop in the barns as washed down these large drains and into the collection vat. I think they used the methane to heat the barns in the winter, but I am not sure. I have seen the plans in the Back to Basics book. I also have plans for a smaller version out of a 1945 popular mechanics projects book.
     
  4. Ariel

    Ariel Active Member

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    since so many people are looking for alternative fuel sources, I am surprised that so few are using this replenishable source. It also appears that you don't need overly sophisticated and expensive equipment.
     
  5. Siryet

    Siryet In Remembrance

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  6. Marcia in MT

    Marcia in MT Well-Known Member Supporter

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    I was talking to an engineer recently, and he said that one of the major problems with methane is that it's a "wet" gas, and that drying the water out of it takes more energy than the methane produces. At least in large operations, so it's not economical.

    I remember reading about the individual burner set-ups in India in the Mother Earth News a long time ago, but I haven't heard anything else either, and have wondered how it could be made to work on a small scale basis.
     
  7. gobug

    gobug Well-Known Member Supporter

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    Thanks for the link Siryet. Great information. Its ironic that my nephew, an architect interested in sustainable resources, was telling me about this guy less than an hour ago. I guess he has converted some of his farm equipment to run on methane.
     
  8. DayBird

    DayBird Big Bird

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    From reading a post over on General Chat, I "believe" that Shrek has built methane digesters. He never answered my question over there as the thread got lost in all of the political stuff. http://homesteadingtoday.com/showthread.php?t=49513&page=6&pp=30&highlight=methane


    I think he's only harvesting the sludge to use to feed his worms. Lots of little homesteads in Romania have some sort of methane digester behind the barn. They use the fuel to cook with.

    I'm very interested in doing something like this. Why should propane have all the fun?
     
  9. Ross

    Ross Moderator Staff Member Supporter

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    It is corrosive as produced and has to be cleaned of the hydrogen sulfide. Not sure of the details my SIL works at the waste wate treatment plant not for from here and they harvest the methane from the sewage digestors to run the boilers. I'll ask her what she know about it. (not really her dept though) Mother Earth news printed a book in the 70's called the Handbook of Homemade Power (or something close) and it has some interesting articles that would be a good introduction to methane and a few other topics. Probably only available used though.
     
  10. mightybooboo

    mightybooboo Well-Known Member

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    Siryet,great link,thank you!Where did you find them,or do you have the CD-Roms?If you have the CDs,were they worth the price?
    BooBoo
     
  11. gobug

    gobug Well-Known Member Supporter

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    I believe the link posted above indicates the gases can be separated in a vertical column. Carbon dioxide was specified as a problem that would settle to the bottom and can be drained. Methane is heavier than hydrogen sulfide, so hydrogen sulfide might rise if it was allowed to set for awhile. I didn't see hydrogen sulfide mentioned as a problem in the articles, but I read through them quickly.
     
  12. Nevada

    Nevada Voice of Reason Supporter

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    Since I'm a retired chemical engineer, I may be able to help with this one.

    While hydrogen sulfide is a problem with oil/gas wells, I doubt that you will have concentrations from biogenic sources that will hurt anything. However, if there happens to be an offensive odor hydrogen sulfide is easy to remove because it is so reactive. Just bubble it through a weak (maybe 5% by weight) sodium hydroxide/water solution. Lye from the supermarket should be a satisfactory source of sodium hydroxide.

    Carbon dioxide may or may not layer, depending on how you collect your product. You shouldn't need to remove the carbon dioxide if all you intend to do is burn the product gas. Carbon dioxide will act an an inert and simply take a free ride through the burner. We would remove it commercially because we wouldn't want to pay to heat-up the carbon dioxide, but it won't be worth your fooling with.

    I suspect that the major problem you will encounter is to produce enough methane to make it worth your while.