[Stoves] Dung based Biogas Plants

[Keith Addison]

Dear Dr Karve

Thankyou for this information.

For sugar, starch, fats and proteins, is an initial inoculation required?

Best wishes

Keith Addison
Journey to Forever
KYOTO Pref., Japan
http://journeytoforever.org/

 

>I started experimenting with biogas generation only in 2003. But as a
>biologist, I was always interested in this technology. A bit of information
>that I obtained in 1983 in the course of a presentation that I attended at
>The Institute of Biology II, Freiburg University, Germany, helped me greatly
>in understanding this process. It was a presentation by two Germany
>researchers. They claimed that practically any organic substance could be
>converted into methane, even benzene or petroleum. The researchers used a
>long, spirally laid plastic tube filled with a dilute emulsion of dung. They
>introduced, at a time, only one specific organic material as the substrate,
>and passed it slowly through this tube. It took several weeks for the system
>to get adapted to the substrate, but after the system had started to produce
>methane, they found that the bacteria conducting a specific step in the
>conversion, occupied a specific zone within the tube. Thus, if the substance
>had to go through conversion stages from A to F, the bacteria in the first
>section would convert A to B. then came the zone in which B was converted to
>C, followed by zones of conversion from C to D, D to E and E to F. The
>methanogenic zone was always the last one. With this system they could show,
>that if a substance was not directly digestible by the methanogens, the
>concerned substance was degraded, step by step, by several other species of
>bacteria, that conducted the intermediate stages of conversion, before
>offering it to the methanogens. The main theme of the presentation was
>conversion of mother liquor from a paper factory into methane, but the
>experiments with the long plastic tube not only impressed me, but also
>helped me in understanding the process of biomethanation. It also raised
>several questions in my mind. Since our intestines also represent a tubular
>system, does the plastic tube model mimic the intestine? Are there zones in
>our intestine that are occupied by a particular species of bacteria? Is this
>nature's way of detoxifying material that is not directly digestible by the
>animal system?
>My experiments later on showed that the methanogens can directly digest
>sugar, certain polysaccharides like starch, mucilages, etc., and also fats
>and proteins. All the above substances yield roughly 250 g methane from a kg
>of substrate. When one uses cellulose, the methane production is just half
>as much as from sugar or starch, and the reaction time is doubled, because
>the material must first be digested by cellulolytic organisms, before the
>methanogens can take over.
>All the facts mentioned above, and even the plastic tube experiment, may be
>quite well known to persons who have systematically studied biomethanation.
>But I thought that the above information might be of interest to neophytes.
>Yours
>A.D.Karve

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