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i wish i had good news, this is going to be a lack-of-progress report;
and that's a damn shame because these surface combustion burners can
give you as much freedom in design as you could want, without worries of
flame length, incomplete combustion, pollutants....
There seem to be several ways to make a surface combustion burner:
the flameless catalytic ceramic types are only available as solid panels
and i have ruled out all the ceramic 'foam' panels as too fragile.
This is a clip from an article:
Burners in Textile Mills
In the winter months, some textile mills switch from natural
gas to a mixture of propane and air to reduce operating
costs. However, ceramic infrared burners are sensitive to
this switch and may be able to handle only a narrow input
band (BTU/ft2). If the burners are under-fired for a few
minutes, they will flashback. Flashback occurs when a
flame front moves through the burner deck or flame holder.
Propane, having a lower ignition point and higher flame
speed than natural gas, increases the risk of flashback in
this situation. Flame speed is the rate at which a flame
progresses into a combustible mixture relative to the speed
of the mixture.
As a result of the shock wave created by a flashback,
ceramic tiles can literally break and fly out of the burner,
resulting in a line shutdown, lost production time and replacement
expenses. By introducing metal fiber gas burners into textile
applications that use ceramic burners, flashbacks and line shutdowns
can be eliminated.
So that seems to leave metal fiber and ceramic fiber.
The Korean site that Peter mentioned is a manufacturer of Fecralloy
which appears to be the best porous surface material available
The English pages of the site seem to be gone;
The Korean front page is here:
[
www.acod.co.kr]
i never tried to get a price out of them.
Furious George said he was going to nuke Korea
so it seemed like a bad time to place an order.
The Acotech site starts here:
[
www.acotech.com]
The site is great for learning about surface combustion;
watch for links to additional pages at the very bottom of a page.
They have random weave Fecralloy for sale in panels;
the perforated, knitted panels are only available as complete burners.
Go ahead and ask about prices if you want a shock.
[better turn off your voice-recognition software when you see the reply].
Southwest screens & filters also has Fecralloy ... as a filter material ... ok fine ...
It won't have the perforations needed for the higher levels of burner output
but it should work ok as a radiant burner.
[
www.swfilters.com]
[
www.swfilters.com]
[
www.swfilters.com]
The filters look much like the cylindrical rod burners on other pages
except there is a supporting cage on the outside.
They listed these materials available : plain steel - stainless steel - copper - bronze -
- aluminium - Inconel - Monel - Hastelloy - Fecralloy
and there is a wide variety of mesh patterns and densities for the wire filters.
Does Inconel sound like a good choice?
They have offices in Belgium and Indonesia ...
i don't think i want to import the stuff
so i need to try to find the local distributors of their products...
Another interesting find is Ceramat.
It's ceramic fiber coated with silicon carbide, formed into a random weave mat
with the fiber crossings welded together. Comes in perforated and nonperforated.
Best of all, it has none of the health risks associated with ceramic fibers.
Details here:
[
www.us.schott.com]
They have an outlet in California.
After four emails i still don't have a price quote,
because
"they only have an email address for an identity,
and they have a policy of never giving a price quote
unless they are certain of the identity of the recipient."
They want me to phone germany and have a chat ....
They can go suck a zeppelin.
Peter, about that 'confidential' price quote, you are not bound by anything they say.
You asked for a price, they gave it, THEN they say there is something 'confidential'
about the information ... bullshorts ... the price is shameful not confidential.
There is an interesting concept at the lower part of this page:
[
www.tokyo-gas.co.jp]
a boiler where there are tubes deliberately put into the flame
to reduce the combustion temperature to reduce pollutants.
There is a combustion space beyond these tubes where combustion is completed,
followed by a conventional tube stack...
i've never seen a design like that before.
There is another source of surface combustion material, Alzeta.
[
www.alzeta.com]
Their product is a ceramic called Duratherm
[
www.alzeta.com]
Jim was going to check this out;
they are 10 miles from his home.
i can't locate the link for the burner manufacturer in India.
I probably have it in archived mail but it's not really worth the search.
The significant thing about the site was the way they made burners;
they used stainless wire [alloy unknown] , not really that exotic.
In some side mail with Jim and Peter, [not Heid ... must be Jeckyl ]
it came out that Coleman made a small radiant burner out of stainless wire screen.
It was formed in a sherical shape and resembled the protective weave on a microphone.
It used a bunsen type air - fuel mixer and you would connect it to a propane source.
You light it, and the flame is on the outside of the screen. You then blow on the flame
to move the flame inside the sphere of wire ...
now the whole sphere glows and emits a lot more infrared.
Point to this is, these things can be home made.
Seems that no matter what material i'm looking at [except catalytic ceramic]
all the burner ratings start at 32000 BTU per square foot and reach the start of
blue flame mode about 150000 to 200000 BTU per square foot whether perforated or not.
This can't be coincidence.
There might be a way to do it with Kaowool and a binder,
but i've already had enough asbestos exposure to last a lifetime,
so i'm not eager to explore the possibility of ceramic mesothelioma.
i'm going to keep looking for more information on metallic mesh burners;
if i find something of interest i'll pass it along.
Anyone have an opinion on Inconel as a suitable metal?
and another concept...
Does it seem reasonable to expect a surface combustion burner to work
with atomized liquid fuel?
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