george koller on fri 9 aug 02
Hello People of the Kilns,
After searching cyberspace for hours I've learned of a class
of instruments designed for measuring some or all of the following
flue gas parameters:
1. Gas Pressure
2. Flow
3. Oxygen
4. Carbon Dioxide
5. Carbon Monoxide
6. Flue gas temps (low temp range)
7. Furnace temps (high temp range)
7. Unburned hydrocarbons (?)
Prices for these instruments, of a seemingly robust and professional
tool nature, ranged from about 450USD up to several thousand USD.
Many of these tools, however, are not designed for continuous
monitoring,
but rather for furnace evaluation by people that do this for a living.
My thought is that perhaps one of these general tools would be useful
to build and verify a kiln schedule, and for verifying the flue gas
situation
at critical points in this schedule, and under special circumstances
(very
high humidity, rain, wind, and etc.)
Would anybody out there care to recommend for or against this type of
tool,
and perhaps explain why measuring only Oxygen inside the kiln seems to
be
the accepted way to go (as far as I'm aware).
Thank you,
George Koller
Sturgeon Bay, WI - Door County
P.S. I've been getting some wonderful but direct responses to my
kiln postings. Of course this is great, and I sincerely appreciate it,
but I'd like to think that others in this group may have some interest
in this issue also.
Gavin Stairs on fri 9 aug 02
At 04:57 PM 09/08/2002 -0500, George Koller wrote:
>After searching cyberspace for hours I've learned of a class of
>instruments ... Prices for these instruments, of a seemingly robust and
>professional tool nature, ranged from about 450USD up to several thousand
>USD. Many of these tools, however, are not designed for continuous
>monitoring, but rather for furnace evaluation by people that do this for a
>living.
>
>My thought is that perhaps one of these general tools would be useful to
>build and verify a kiln schedule, and for verifying the flue gas situation
>at critical points in this schedule, and under special circumstances (very
>high humidity, rain, wind, and etc.)
Dear George,
There is a whole engineering specialty dedicated to designing and operating
burners and furnaces. Industrial ovens, furnaces and other open flame
equipments need to be carefully designed and adjusted to meet the
increasingly onerous regulations of government, not to say the needs of the
owners for economy and clean operation. These expensive instruments are
what they use to do this. The cost of some of these things (flue gas
analyzers, for example) is hefty even to these very large industries. It
can be astronomical for small operators like studio potters.
If you can afford these things, and justify their use in terms of increases
in quality, yields or any other parameter of interest, then go to it. I
imagine that the present use of oxy-probes is taken as an affordable
instrumentation technique which gives an indication of a parameter which is
useful in setting the kiln for oxidation/reduction. Most potters find that
they are able to control their kilns without even this instrument. Why
would they use it, therefore? If your operation is sizable enough to be
able to afford this, you can probably also afford the professional
engineering advice to make it work.
In the case that environmental regulators take an interest in the small
operations of potters, and require them to meet levels of certain emission
parameters like unburnt fuel, particulates or CO or NOx, then some new
stack monitors may be required. I hope this never comes, because this
requirement would probably put many potters out of business.
There is one way that this can be done in a quasi-affordable way. That is
to hire professionals to come and do a one time analysis of a kiln, as you
suggest. However, even this would be quite costly, and any one-shot would
be rather thin coverage. When a new furnace is being brought into
operation, the analysts are usually on site for quite a while, and come
back regularly for follow-up. On the other hand, setting up your domestic
furnace and water heater is usually a one-time or no-time proposition. Pay
your money and take your pick.
Gavin
george koller on sat 10 aug 02
Hello People of the Kilns,
Unbelievable!! Seems that a certain fellow is doing tests
even as I've been surfing and trying to find "a better way".
His solution seems more robust, and many time more
economical than the ones I have thought of! He is
approaching this scientifically and has plotted the results
of his $5.00 solution VS an Oxygen probe with what I
interpret as very encouraging results.
Wow, what a group! If there is additional interest in this
perhaps others would like to encourage him to publish his
findings earlier rather than later....
Another thought I'd like to share is that rather than buy used
for $5 or so these devices are available new for about $75.
Would it make sense for some of us to "standardize" on a
particular model so that notes could be compared with more
constants? (With a Digitial Multi-meter total cost might be
100USD). Just my humble thought.
Best,
George Koller
Sturgeon Bay, WI - Door County
Best,
George
Hank Murrow on sat 10 aug 02
Dear George, student of the kiln;
The CO2 meters were an interesting tool back in the early
sixties, and I liked mine; but was ecstatic to use one of the first
OxyProbes brought into this country. 25 years later, I still love it,
and it has been repaired twice, enclosed in n alumina tube (to
prevent further repairs), and still affords clear and instant
monitoring of the atmosphere after red heat is reached. Comes with a
platinum/rhodium thermocouple which will outlive me, and which
affords great control during the cooling cycle. With appropriate
software, you can even use them to ramp and reduce your gas kiln.
There is a potter in Ontario, OR who is doing this now with his
Bailey. The new Axner Probe comes in a protection tube at around $700.
Best to you, Hank in Eugene
http://www.murrow.biz/hank/kiln-and-tools.htm &
http://www.ceramicsmonthly.org/mustreads/shinofire.asp
>Hello People of the Kilns,
>
>After searching cyberspace for hours I've learned of a class
>of instruments designed for measuring some or all of the following
>flue gas parameters:
>
> 1. Gas Pressure
> 2. Flow
> 3. Oxygen
> 4. Carbon Dioxide
> 5. Carbon Monoxide
> 6. Flue gas temps (low temp range)
> 7. Furnace temps (high temp range)
> 7. Unburned hydrocarbons (?)
>
>Prices for these instruments, of a seemingly robust and professional
>tool nature, ranged from about 450USD up to several thousand USD.
>Many of these tools, however, are not designed for continuous
>monitoring,
>but rather for furnace evaluation by people that do this for a living.
>
>My thought is that perhaps one of these general tools would be useful
>to build and verify a kiln schedule, and for verifying the flue gas
>situation
>at critical points in this schedule, and under special circumstances
>(very
>high humidity, rain, wind, and etc.)
>
>Would anybody out there care to recommend for or against this type of
>tool,
>and perhaps explain why measuring only Oxygen inside the kiln seems to
>be
>the accepted way to go (as far as I'm aware).
>
>
>Thank you,
>
>
>George Koller
>Sturgeon Bay, WI - Door County
>
>
>
>P.S. I've been getting some wonderful but direct responses to my
>kiln postings. Of course this is great, and I sincerely appreciate it,
>but I'd like to think that others in this group may have some interest
>in this issue also.
>
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>
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>melpots@pclink.com.
Ned Ludd on sun 11 aug 02
Hank Murrow wrote
>The CO2 meters were an interesting tool back in the early
>sixties, and I liked mine; but was ecstatic to use one of the first
>OxyProbes brought into this country. 25 years later, I still love it,
>and it has been repaired twice, enclosed in n alumina tube (to
>prevent further repairs), and still affords clear and instant
>monitoring of the atmosphere after red heat is reached.
Hi Hank
By the way, thank you for your post clarifying details about your
sixty-holer teapot. With respect, it is obvious you are a Teaman. I
think us potters of like ilk, who revere Tea, should start an occult
society.. Latin and Oriental titles... mandarin robes...secret
handshakes ... monthly TeaGirl or TeaBoy magazine complete with
mouthwatering centerfold... you get the picture...
Now you've intrigued me again, this time with that alumina tube.
My Axner oxyprobe, now with eight firings to its credit, has
performed perfectly - after an initial fault that the company
repaired promptly.
But the unglazed porcelain tube it came with has broken in three
places, despite the utmost care in handling and storing. Replacements
are not cheap, and seem a waste of time and money if they are liable
to break so easily.
Is the alumina tube that you refer to any improvement on Axner's
standard tube? If so where is it obtained?
best
Ned
Hank Murrow on sun 11 aug 02
>Hank Murrow wrote
>
>>The CO2 meters were an interesting tool back in the early
>>sixties, and I liked mine; but was ecstatic to use one of the first
>>OxyProbes brought into this country. 25 years later, I still love it,
>>and it has been repaired twice, enclosed in n alumina tube (to
>>prevent further repairs), and still affords clear and instant
>>monitoring of the atmosphere after red heat is reached.
>
>Hi Hank
>By the way, thank you for your post clarifying details about your
>sixty-holer teapot. With respect, it is obvious you are a Teaman. I
>think us potters of like ilk, who revere Tea, should start an occult
>society.. Latin and Oriental titles... mandarin robes...secret
>handshakes ... monthly TeaGirl or TeaBoy magazine complete with
>mouthwatering centerfold... you get the picture...
**** I love these pots for Sencha (green leaf tea). The first time I
whisked some Matcha (powdered green tea) in one of my Black Seto
hikidashi bowls, I was a goner! That Green! That Black! I hear that
someone down south is making woodfire tumblers for the great American
Iced tea Ceremony!
>
>Now you've intrigued me again, this time with that alumina tube.
>My Axner oxyprobe, now with eight firings to its credit, has
>performed perfectly - after an initial fault that the company
>repaired promptly.
>But the unglazed porcelain tube it came with has broken in three
>places, despite the utmost care in handling and storing. Replacements
>are not cheap, and seem a waste of time and money if they are liable
>to break so easily.
>
>Is the alumina tube that you refer to any improvement on Axner's
>standard tube? If so where is it obtained?
*** Never having seen the Axner, I can't comment, but I get
my tubes from Nils Lou. They have performed flawlessly for years.
Ping him and see if he still has some.
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