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<DIV><FONT size=2 face=Arial>I built a 1000L small scale digester about 10 years
ago which incorporated chamber heating via solar hot water circulation as
well as a biogas fired heat-exchanger as a back-up for cold nights.
</FONT></DIV>
<DIV><FONT size=2 face=Arial>The system could readily achieve blood temperature
and maintain this with minimal management and a small amount of electricity
to drive the circulation pump intermittantly.</FONT></DIV>
<DIV><FONT size=2 face=Arial>A solar powered pump would have been
sufficient.</FONT></DIV>
<DIV><FONT size=2 face=Arial>I was not so interested in the biogas component at
the time as the unit was readily able to produce 2 cubic meters of up
to 90% methane per day and I had no other use for this gas other than to flare
it off. </FONT></DIV>
<DIV><FONT size=2 face=Arial>I used the gas volume as an indicator of
digestation reactivity and a determinant for retention time.</FONT></DIV>
<DIV><FONT size=2 face=Arial>My interest was in the spent digestate,
particularly the colloidal nutrient contained within it. </FONT></DIV>
<DIV><FONT size=2 face=Arial>The bio-gas was a bonus, the fertilizer was beyond
compare. </FONT></DIV>
<DIV><FONT size=2 face=Arial>I split the digestate into colloidal liquid and
pelletized the remainder. </FONT></DIV>
<DIV><FONT size=2 face=Arial>The colloids were sprayed as a foliar feeder and
the pellets fed the soil and plant roots. Carbon content of the soil was raised
considerably. Plant growth was exceptional and the fertilizer would enable the
growth of vegetation on long term bare ground (at least 20 years
barren) which would not previously support any growth at all. The
full-scale plant (38,000L) was reproduced in India and achieved 22% better
output results than I managed with the prototype. They called it the
BioBowser.</FONT></DIV>
<DIV><FONT size=2 face=Arial>Peter Allison. </FONT></DIV></BODY></HTML>