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<DIV><FONT face=Arial size=2><STRONG>Hi Peter,</STRONG></FONT></DIV>
<DIV><FONT face=Arial size=2><STRONG>Sorry but only brief answers to your
questions:</STRONG></FONT></DIV>
<DIV><FONT face=Arial size=2> <BR>> Looking at your excellent report and
photo's on your archives page (yes <BR>> we have bowed to pressure and are
organising someone to do something <BR>> similar for our own work, will post
a link to list in due course) I note <BR>> the flare colours are similar to
what we used to get from our early <BR>> models, though if the operation was
at the 320Nm3/hr level for the <BR>> daylight photos then we have to
get better gas flow measurements <BR>> ourselves as the flare volumes
depicted are what we would expect from <BR>> the system with the fan at low
speed. Perhaps you did not have the <BR>> gasifier at full flow when the
pictures were taken?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2><STRONG>Open flare testing was conducted at low
levels due to the fire hazards present in California. Water sprays were used to
wet the area of the tests.</STRONG></FONT></DIV>
<DIV><STRONG><FONT face=Arial size=2></FONT></STRONG> </DIV><FONT
face=Arial size=2>
<DIV><STRONG>The two daylight photos were to show the first cold start-up gas,
first at ignition, then a little later as the exothermic heat began to return to
the gas making, not heat soaking. Cold start-ups are never conducted at high
flows,</STRONG> <STRONG>because you will consume all the char before the raw
fuel can be carbonized.<BR>The night photos were done to show at a higher rate,
how the exiting combustible gas changes in volume, as the amount of
pyrolysis gas from the raw fuel over the bed
</STRONG><STRONG>either fails to flow or in our case, not fed quickly enough to
keep up with the required gas making quality.</STRONG> <STRONG>Night photos
provide the best view of these changes. The colors of the gas relate to a known
% of clean gas free from hydrocarbons, and a particulate level consistent with
prior testing. </STRONG></DIV>
<DIV><STRONG></STRONG> </DIV>
<DIV> > Just a clarification: When you talk about air blown you are
referring to <BR>> the fan forcing air in rather than drawing gas out? </DIV>
<DIV> </DIV>
<DIV><STRONG>The short answer is yes, but fans are not appropriate for
commercial gasifiers. You need a Roots blower which is a positive displacement
pump (suction or blown) then you will see how your gasifier really behaves. Fans
just spin and you cannot have any control over any obscure changes in pressure
or suction.</STRONG></DIV>
<DIV> </DIV>
<DIV>>We did play with <BR>> this at one stage and whilst it looked
promising the level of instrument <BR>> control required was beyond our
skills and resources at the time and <BR>> negated our advances in "open
core" operation. Though it did make an <BR>> interesting Updraft/Downdraft
hybrid blowing gas out both ends when the <BR>> top lid was opened! </DIV>
<DIV> </DIV>
<DIV><STRONG>When you are forced to use only manual refueling, many design
issues do not have to be addressed, but go automation, you will start to need
all those $$$.</STRONG></DIV>
<DIV> </DIV>
<DIV>>I see you have addressed this somewhat with a <BR>> divorced feed
system via a cross flow auger. We also looked at ram type <BR>> plug feeders
as a auger alternative, but all these things increase <BR>> complexity, cost,
maintenance requirements and parasitic electric loads, <BR>> the opposite of
our core philosophy of KISS. Though we would stress this <BR>> in no way
negates their validity or value where the situation warrants.</DIV>
<DIV> </DIV>
<DIV><STRONG>Unless the inflow refueling point is at ground level, fuel has to
be lifted and that take energy. You just cannot open the top of a gasifier to
atmosphere as the ingoing fuel will displace gas, this requires a fuel lock.
Screw augers cannot provide a reliable plugging effect blown or on suction, that
is if you are using say woody biomass, and ram types are not appropriate for
linear hearths. Not sure how you would consider any of the known basic
automated components as redundant in the search for
KISS.<BR></STRONG> </DIV>
<DIV>> We are now (finally!) moving to a full commercial design suited to
ease <BR>> of replication, having spent much of the last 2years on this
aspect <BR>> rather than gasifier operation itself which has been more than
<BR>> satisfactory. We are now planning the fabrication of a 250kg/hr model
<BR>> and +500kg/hr model, </DIV>
<DIV> </DIV>
<DIV><STRONG>From what you say, you had better get that refueling system sorted
first. Moving the fuel and it's type in the volume required will stretch
mechanical skills.</STRONG></DIV>
<DIV> </DIV>
<DIV>>the former for retro fitting and dual fueling <BR>> diesels and the
latter for matching to an optimised low btu gas engine <BR>> 500kWe genset
from our new Malaysian partners later this year. The large <BR>> throat size
again a concession to material handling of lighter mixed <BR>> biomass feed
stocks rather than a need to build a single module for the <BR>> scale of
job, who knows what other break through s this change might <BR>> lead
to?</DIV>
<DIV> </DIV>
<DIV><STRONG>Well we will look forward to seeing your creations shortly when you
get organized. </STRONG></DIV>
<DIV><BR> > I know I am occasionally to frustrated in my writings, the
negative <BR>> experiences with industry peers in the fair land of Oz
coloring my <BR>> outlook to a degree, but I remain as others have in their
long careers, <BR>> eternally optimistic that a new age of gasification is
dawning, and even <BR>> if it isn't we are enjoying the journey
anyway!<BR></DIV>
<DIV><STRONG>When I used to teach my girlfriends how to drive, I told them look
for potholes down the road, not when they are in front of the wheels. Keep an
eye on where gasification may take you, because the destination is going to be
set by the small details, not the potential grandeur of it's
application(;-)</STRONG></DIV>
<DIV><STRONG></STRONG> </DIV>
<DIV><STRONG>This is all I can offer for a while, but glad some found it
interesting.</STRONG></DIV>
<DIV><STRONG></STRONG> </DIV>
<DIV><STRONG>Doug Williams,</STRONG></DIV>
<DIV><STRONG>Fluidyne.</STRONG></DIV>
<DIV><STRONG></STRONG> </DIV>
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<DIV><STRONG></STRONG> </DIV>
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