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Yvonne,<br>
</font><br>
On 10/28/2010 1:53 AM, Voegeli, Yvonne wrote:
<blockquote
cite="mid:1AA2B5DF4E6B214A875A9D353997ADEA022047D6FB35@EAW-EXC-MAIL.eawag.wroot.emp-eaw.ch"
type="cite">
<div class="Section1"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;"><o:p></o:p></span></font><font
face="Arial" size="2"><span style="font-size: 10pt;
font-family: Arial;">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....<o:p></o:p></span></font>
<p class="MsoNormal"><font face="Arial" size="2"><span
style="font-size: 10pt; font-family: Arial;"><o:p> </o:p>...Is
it possible to install a simpler venting system?</span></font></p>
</div>
</blockquote>
<br>
I would venture a guess that where the inlet air is being forced in
by bubbling through water, and the outlet air likewise is allowed to
escape by bubbling through water, then the only place in the system
where there would be both a potentially explosive gas mixture and
the potential of a spark would be at the evacuation point of the
exiting gas mixture. Where sufficient air is blown over the water
through which the evacuating air is exiting, then the risk of any
explosion would, I would think, be very close to zero.<br>
<br>
<br>
<br>
d.<br>
<div class="moz-signature">-- <br>
<div style="" ;=""><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>
</code></div>
<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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