Yvonne Hi! When you say developing countries, what sort of construction
materials are you thinking of? Would old 20 tonne shipping containers be
available?
Are cement materias and tradesmen skilled in cement plaster work readily
available? What about PVC tarpaulin cloth? Are there trucks on the roads
that have waterproof covers that can be strapped down over a load? What is
the local soil and terrain? Is it possible to dig say 2-3 metres deep in the
soil and get a smooth surface, or is the terrain too soft and sandy to hold
to the shape of a cistern or trench dug in the soil? Is it too rocky to allow
any sort of digging at all? If you can home in a little more on the country
side and local skills available I can make several different suggestions.
Sincerely, Ken Calvert. www.coffee.20m.com
----- Original Message -----
From: Voegeli, Yvonne
To: [email protected]
Sent: Thursday, October 28, 2010 9:53 PM
Subject: [Digestion] Dry fermentation in developing countries
Dear all,
I like to start a new discussion on a different topic, namely the
dry-fermentation process (discontinuous) similar to the digesters developed by
the companies Bekon or Bioferm in Germany. The organic waste is filled
batch-wise into simple garage-like digesters for about 30-40 days.
Experts report that this process has a high potential for application in
developing countries as it has the simplest design and the solid waste
digesters are the least expensive ones. Also, substrates that lead to operating
problems during wet fermentation due to their structure or the proportion of
impurities they contain can still be processed using dry fermentation methods.
However, up to date, there is no experience with this technology in developing
countries. Therefore, our idea is to develop a dry-fermentation biogas plant
adapted to the situation in developing countries using locally available
material.
After visiting a Bekon biogas plant in Switzerland, I'm especially concerned
regarding the opening of the digester for emptying and refilling. Before
opening the door, the digester has to be vented in order to avoid a
gas-air-mixture which is explosive. This installation seems to me rather
complicated.
- Is anybody of you familiar with discontinuous dry-fermentation systems and
has an idea how the security can be assured in a developing country context? Is
it possible to install a simpler venting system?
- Likewise, when removing the drum from a floating-drum digester for
emptying, how is ensured that at no time an explosive gas-air-mixture occurs?
Thanks for your ideas,
Yvonne
°°°
Yvonne Vögeli
Eawag / Sandec
Überlandstrasse 133
P.O. Box 611
8600 Dübendorf
Switzerland
Phone: +41 (0)44 823 54 20
Fax: +41 (0)44 823 53 99
[email protected]
http://www.sandec.ch
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and the Biogas Wiki http://biogas.wikispaces.com/
_______________________________________________
Digestion mailing list
to Send a Message to the list, use the email address
[email protected]
to UNSUBSCRIBE or Change your List Settings use the web page
http://lists.bioenergylists.org/mailman/listinfo/digestion_lists.bioenergylists.org
for more information about digestion, see
Beginner's Guide to Biogas
http://www.adelaide.edu.au/biogas/
and the Biogas Wiki http://biogas.wikispaces.com/
