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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>G’day Matt,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I don’t often check the wiki but I do sort of recall
seeing the questions you left, which I will answer below (and put back on the wiki!).<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I also distrust steel mesh as a flame trap, but it works by
removing the heat and you could use stainless steel pot scourers for a small
unit.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I hope this is some help and am happy to answer further
questions,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>All the best,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>HOOROO<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal>In flametrap 1, it seems that the pressure relief container
should have a greater water depth than the container through which the gas is
bubbling. Wouldn't the greater water pressure of deeper water stop the gas from
bubbling? If not, then why doesn't it bubble out of the pressure relief? I'm
sure there's something I don't understand.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='color:#002060'>If you start from the burner and
work back it may help a little. Let’s say the burner needs 2 cm water,
which means the water in the pressure relief will be 2 cm different in height
and you may have another 2 cm of pipe depth to make sure gas doesn’t leak
out un-necessarily. Now if the flame trap pipe is 6 cm into the water the
digester pressure will have to be 2 cm burner pressure plus 6 cm flame trap
pressure or a total of 8 cm of water.</span><br>
<br>
In flametrap 2, I'm assuming that there is supposed to be water inside. If
that's the case, I'm having trouble understanding the pipe on the right side of
the diagram (near the words "normal (burner) pressure"). Is this a
pressure relief that works like a manometer? <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='color:#002060'>You are right on both counts,
water is used again and it collects in the first U bend that acts as a flame
trap then excess water is pushed out the second U bend that also functions as a
pressure relief. I thought of this one as it is easier to screw pipes fittings together
than weld containers. The only disadvantage I can see is the limited water
storage in the first bend that may not hold back a large pressure surge caused
by a backfire, but if the digester tube is smallish the inertia of water may
mean the job is done. All parts need to be metal!</span><br>
<br>
I understand that I can make a flame arrester using wire mesh, but I don't know
where to get stainless or brass mesh here in the Philippines. I like the simple
idea of bubbling through water but I'm getting confused looking at the
diagrams. <br>
<br>
Thanks in advance for your help.<span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;
color:#1F497D'>Mr. Paul Harris, Room S116b, Waite Main Building Faculty of
Sciences, The University of Adelaide, Waite Campus, PMB 1, Glen Osmond SA
5064 Ph : +61 8 8303 7880
Fax : +61 8 8303 4386 <a
href="mailto:paul.harris@adelaide.edu.au">mailto:paul.harris@adelaide.edu.au</a>
<a href="http://www.adelaide.edu.au/directory/paul.harris">http://www.adelaide.edu.au/directory/paul.harris</a><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;
color:#1F497D'>CRICOS Provider Number 00123M<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas;
color:#1F497D'>This email message is intended only for the addressee(s) and
contains information that may be confidential and/or copyright. If you
are not the intended recipient please notify the sender by reply email and
immediately delete this email. Use, disclosure or reproduction of this email by
anyone other than the intended recipient(s) is strictly prohibited. No
representation is made that this email or any attachments are free of viruses.
Virus scanning is recommended and is the responsibility of the recipient.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> digestion-bounces@lists.bioenergylists.org
[mailto:digestion-bounces@lists.bioenergylists.org] <b>On Behalf Of </b>Matt
Lorig<br>
<b>Sent:</b> Tuesday, 14 December 2010 12:30 PM<br>
<b>To:</b> Digestion@bioenergylists.org<br>
<b>Subject:</b> [Digestion] flame trap/ flame arrester<o:p></o:p></span></p>
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<p class=MsoNormal>Hello, <br>
<br>
I have a Chinese style AD unit for my pig farm here in the Philippines.
I would like to improve the safety of my system by installing some kind of
flame trap or flame arrester to make it impossibe for the flame to travel up
the gas pipe to the tank. I know that I can use a mesh screen but I'm
not sure if I can get suitable materials here that won't corrode. I
like the simple idea of bubbling the gas through water. I've looked the the
flametrap designs on the safety page of the Beginners Guide to Biogas, but
I'm having trouble understanding the diagrams.<br>
<br>
http://www.adelaide.edu.au/biogas/safety/flametrap.jpg and <br>
http://www.adelaide.edu.au/biogas/safety/flametrap1.jpg<br>
<br>
I posted specific questions about the diagrams on the biogas wiki, but so far
no response.<br>
<br>
http://biogas.wikispaces.com/message/view/Questions/30782495<br>
<br>
Any help or ideas would be greatly appreciated.<br>
<br>
Thanks.<br>
Matt Lorig<br>
mattlorig@yahoo.com<o:p></o:p></p>
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