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Alex,<br>
<br>
</font>On 11/23/2011 6:09 AM, <a class="moz-txt-link-abbreviated" href="mailto:alexanderb.eaton@gmail.com">alexanderb.eaton@gmail.com</a> wrote:
<blockquote
cite="mid:988723432-1322057350-cardhu_decombobulator_blackberry.rim.net-482317333-@b13.c13.bise6.blackberry"
type="cite">Do we think that this is related to C:N or the surface
area of the carbon matrix or other? Has anyone applied this? It
seem that maybe periodic feeding of carbon may work, rather than
daily. Thoughts relative to small digesters?
</blockquote>
<br>
As it turns out, this publication is available on the web, <a
href="http://www.scribd.com/doc/70129379/A-Note-on-Stimulation-of-Biogas-Production-From-Cattle">here</a>,
so you can make your own judgement. The article offers what I would
say is a speculation:<br>
<br>
<blockquote>The increase in gas production caused by the addition of
charcoal may be attributed to enhanced microbial activity in the
digester contributed by growth of bacteria on the surface of the
carbon particles (Adams, 1976). This is corroborated by the
results of studies on microbial profiles of the digesters (Table
5) which showed that the slurry amended with charcoal had higher
microbial numbers than the unamended slurry.<br>
</blockquote>
<br>
The peculiar thing in this report is that charcoal from different
sources had such different effects, which would tend to indicate
that whatever is responsible for changes is something that can be
strongly affected by factors such as (perhaps) the type of wood and
the method by which it is made into charcoal. Changes in the surface
characteristics of the charcoal might be expected to have an impact
on the characteristics of the biofilm which is subsequently
supported thereon, but as yet, certainly based on this one report,
and at least as far as what I have seen in the literature if not
indeed, it would seem that we do not have a reliable answer as to
the causes of any improvements.<br>
<br>
<br>
d.<br>
<div class="moz-signature">-- <br>
<div style="font:Georgia" ;=""><span style="font-size:110%;">David
William House<br>
</span>
<div style="padding-left:3em;font-size:80%;">"The Complete
Biogas Handbook" <code><a href="www.completebiogas.com">www.completebiogas.com</a></code><br>
<em>Vahid Biogas</em>, an alternative energy consultancy <code><a
href="www.vahidbiogas.com">www.vahidbiogas.com</a><br>
<br>
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<div style="padding-left:2em;">"Make no search for water.
But find thirst,<br>
And water from the very ground will burst."
<div style="padding-left:2em;font-size:80%;">(Rumi, a
Persian mystic poet, quoted in <em>Delight of Hearts</em>,
p. 77) <br>
<br>
<a class="moz-txt-link-freetext" href="http://bahai.us/">http://bahai.us/</a></div>
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