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<DIV><FONT face=Arial size=2><STRONG>Hi Andy,and
Colleagues,</STRONG></FONT></DIV>
<DIV><STRONG><FONT face=Arial size=2></FONT></STRONG> </DIV>
<DIV><STRONG><FONT face=Arial size=2>It's been a while since we have heard from
you, but hope you won't mind my reply in the text of your
message:</FONT></STRONG></DIV><FONT face=Arial size=2>
<DIV><BR> At Abu grab in Iraq, Bruce Jackson had good sucess gasifying
charred shipping pallet-wood.</DIV>
<DIV> </DIV>
<DIV><STRONG>That seems like a long time ago now, but I remember Bruce had it
tough, and gasification gave him a tool to handle his stress.</STRONG></DIV>
<DIV> </DIV>
<DIV> I've since become friends with Bruce and have visited his camp in
Michigan. He operates gasified four-cylinder tractors for powering saws in the
bush.</DIV>
<DIV> </DIV>
<DIV><STRONG>He invited me down if I ever got into the area, but never did
except on Google Earth. Seeing the beauty of his area, no wonder Iraq took
a chunk out of his soul.</STRONG><BR><BR> Our Friend Greg Manning says most
understandably that slipped-char is the "conveyor-belt for ash". This makes
sense to me. A hearth can plug up quickly with fines, if not removed
continuously.</DIV>
<DIV> </DIV>
<DIV><STRONG>I haven't heard it described like that before, but yes, moving char
beds prevent the ash from staying in one place where they can melt and
cause problems.</STRONG><BR><BR> When driving moderate distances on wood
blocks last year, I became flooded with quantities of excess char removed from
my imbert ash-pit. I bagged up the char, and gave it to friends involved with
cutting and removing a prolific tree-species that had begun to displace native
beech/maple stands. They burned the char to ash in a special pizza oven during
their autumn music-fest just for fun. They had been using raw wood in the oven,
but it smoked objectionably during the party the year before. They loved the
char product.</DIV>
<DIV> </DIV>
<DIV><STRONG>Well charcoals are well known as a smokeless fuel, even used inside
in table stoves in some cultures. After smoky wood, who wouldn't love
it(:-) </STRONG></DIV>
<DIV><BR>Visiting Jim Mason's shop this spring, and talking with biochar
experimenters there, I learned the char from my imbert may not be most useful
for gardening, because my char is made at temperatures way higher than
temperatures at which the most beneficial biochar is made.</DIV>
<DIV> </DIV>
<DIV><STRONG>With so many now involved with biochar production, because it is
the in thing, you will hear many say this or that! Because the char from
gasification can vary across a wide spectrum of quality and optimum end
application, you can only discuss the char that you have left over from your own
equipment.</STRONG></DIV>
<DIV><STRONG></STRONG> </DIV>
<DIV><STRONG>For what it is worth to know, a traditional Imbert with a lower
grate under the Bell reduction zone, has two types of char in that mass we call
the reduction zone. The core char down to the grate is just supporting the total
char mass right up through the gasifier. It doesn't move naturally until shaken.
The gas flow through the throat follows the suction, and takes the shortest
route through the bed, down the walls of the bell. This char is the reduction
char, and the support pyramid of char remains just charcoal, because it is not
swept by incandescent CO2. If you have a grate vibration that very slowly drops
the char, then there is a more consistent quality of the char closer to the
properties of the reduction char. This can be described a
slippage.</STRONG></DIV>
<DIV><STRONG></STRONG> </DIV>
<DIV><STRONG>Now having said all that, reduction char should be very light and
porous, not heavy and dense, because it is activated carbon (of varying
quality). As such, it is ideal for soil applications, because it's porosity
provides a habitat for soil bacteria. A test we had done in Germany, found it
was good enough to clean the condensate from the gas cooling, but there were no
tars present. </STRONG></DIV>
<DIV><STRONG></STRONG> </DIV>
<DIV><STRONG>The harder heavier charcoals are more directly applicable to carbon
sinks. The bottom line is that differing woods and the char they might make as a
waste out of a gasifier, are not easy to discuss other than in a general
way. I have friends who specialize in char making, and they are very
focused on how they grade and make char to specifications.</STRONG></DIV>
<DIV><BR>Excess quantities of char required for cooking pizzas at parties will
be expected when heavier imbert gasification use of this invasive-species
biomass is at the higher potential.<BR>The trees sprout anew from cut stumps
faster than the boys in the woods can saw, and skid.</DIV>
<DIV> </DIV>
<DIV><STRONG>If that is the only local use for these coppicing trees, then
you either eat a lot of pizza after making charcoal, or you get the local
gasified power generation going into the grid.</STRONG><BR><BR> What size
char is good for the charcoal cross-draft you described? No dust I
assume..</DIV>
<DIV> </DIV>
<DIV><STRONG>All these charcoal gasifiers like evenly graded charcoal, and the
size will depend on the species. I would aim for a walnut size if hardwood, and
half fist size for say pine or soft wood. The dust can go to
compost.</STRONG></DIV><STRONG>
<DIV><BR></STRONG>The engine displacement-fit here is about 5 Liter, give or
take 1/2 L.</DIV>
<DIV> </DIV>
<DIV><STRONG>They used single nozzle systems for big engines during WW2, so
other than making sure the nozzle has plenty of water cooling to prevent
it melting, you should have a lot of fun playing with the concept. It should be
less of a challenge than cherry pits(:-)</STRONG></DIV>
<DIV><STRONG></STRONG> </DIV>
<DIV><STRONG>Regards,</STRONG></DIV>
<DIV><STRONG>Doug Williams.</STRONG></DIV>
<DIV><STRONG>Fluidyne.<BR><BR><BR></STRONG></FONT></DIV></BODY></HTML>