Re: DIG-L: Low Cost Digesters

[CAVM@aol.com]

In a message dated 3/22/2002 3:14:51 AM Central Standard Time, 
effenberger@tec.agrar.tu-muenchen.de writes:

<< 
 > At a biogas fair in germany, I have seen such a system 
 > offered by a german
 > company. They just fill solid wastes in a tunnel made of 
 > plastic foil (dry
 > fermentation). I cannot remember the name but it is one of the biggest
 > manufacturer of such foils, which are normally used for 
 > silage. Maybe one of
 > the readers can give you more informatins about it. >>


We have looked at the potential for an inexpensive system such as this.  In 
the USA it would be the Ag Bag silage bags that would be used.  There are 
similar large plastic bags made by others.

They are about 6' (2 meters) high and 250' (75 M) long.  They may come longer 
also.

Their intended use is to be loaded by a feeding machine with moist
chopped corn stalks, hay, and other feed materials for dairy cattle.  The 
fermentation process takes place anaerobically over several months and then 
the bag is cut away and the contents fed to dairy cattle.  It makes very good 
feed and is the standard way to cure and preserve feeds for many farms.

If the mix of ingredients were changed, the moisture increased and the gas 
siphoned off, it might make a digester.  The major issues would be leaks, 
since these bags are only built to last a finite period of time in the sun, 
and the inability to mix the contents. Sludge or other floating biomass may 
cover the surface of the digesting liquid and inhibit results.

The last issue I that comes to mind is emptying the long bags of their liquid 
contents when digestion is finished.

Cornelius A. Van Milligen
Kentucky Enrichment Inc.
Byproduct processors

Digestion List Archives:
http://www.crest.org/discussion/digestion/200202/

Digestion List Moderator:
Paul Harris, paul.harris@adelaide.edu.au
http://www.roseworthy.adelaide.edu.au/~pharris
List-Post: <mailto:digestion@crest.org>
List-Help: <mailto:digestion-help@crest.org>
List-Unsubscribe: <mailto:digestion-unsubscribe@crest.org>
List-Subscribe: <mailto:digestion-subscribe@crest.org>

Other Digestion Events and Information:
http://www.bioenergy2002.org
http://crest.org/discussiongroups/resources/biomass/biogas/BIOGASMK.pdf
http://www.crest.org/articles/static/1/1010424940_7.html

Beginners Tour of Biogas
http://WWW.roseworthy.adelaide.edu.au/~pharris/biogas/beginners