Dear Chandler, we use PVC pipes and fittings that are also used by plumbers and which are readily available in all hardware shops. I don't think that the white deposit that you mention is silica. It could be calcium carbonate. Water generally has calcium bicarbonate dissolved it. By combining with one more molecule of carbon dioxide, it forms calcium carbonate, which is insoluble in water and which therefore precipitates out. The pipes can be periodically cleaned of this substance by passing a mild solution of hydrochloric acid through the pipes. Yours A.D.Karve On Tue, Mar 6, 2012 at 1:19 AM, Chandler <[email protected]> wrote:
> Hi all, > > > I am working to implement biogas in East Africa, and I’m curious about > whether there is a preferred plastic polymer for use in plastic biogas > pipework. Most affordable, readily available plastic pipes and fittings > are made from PVC (polyvinylchloride), PE (polyethylene), or PP > (polypropylene). > > - Is one of these materials better than the other two for use in gas > lines? And is there a material that should be avoided for use in > biogas pipework (i.e. due to chemical corrosion, UV damage, or creep?) > > - In particular, I am concerned about the accumulation of white > (silica?) deposits in biogas pipework. Does the use of plastic piping > reduce the buildup of this white substance? And very specifically, does > this white substance accumulate on PP fittings? > > Any thoughts on these two questions are very much appreciated. > > Thanks, > Chandler > > _______________________________________________ > 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/ > > > -- *** Dr. A.D. Karve Trustee & Founder President, Appropriate Rural Technology Institute (ARTI)
_______________________________________________ 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/
