Morgan
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An $88,000 thermos
I was watching this video on a thermos kiln and recalled cutting a tall Stanley thermos apart with a hacksaw years ago. There was this black powder
between the walls and I assumed it was carbon so the other day I searched to verify that's what it might be and came across this exorbitantly priced
repair bill account. It's funny how innocuous items can sometimes surprise you.
DIY Micro Kiln
https://youtube.com/watch?v=Ooabd80A3aQ
So I passed this quirky happening on to the kiln author above. I don't know if there's any dust hazard with today's vacuum thermos bottles but it's
maybe something to keep in mind.
https://www.farmshow.com/a_article.php?aid=18232
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Fyndium
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Why it is filled with carbon? Isn't vacuum the better insulator?
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unionised
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They certainly use charcoal in the vacuum space of cryogenic dewar flasks.
The charcoal gets very cold and cold charcoal does a very good job of absorbing gases- so much so that it produces a better vacuum which makes the
insulation better.
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MidLifeChemist
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Wow, that is a crazy story! Can't believe that happened
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Morgan
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Here's a glimpse of carbon at step 12.
https://youtu.be/01af9y7PDKk
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Morgan
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A thermos cut in half revealing the carbon.
https://youtube.com/watch?v=WzutESmEJaA
Viewer comment
"What exactly was that insulating material? Or were they smuggling heroin?"
Another thing about sealed vessels, this video reminded me of the time I gelled some guar gum in water with some green dye. It made a slug of material
that would slide up and down the glass jar if inverted but if shaken briskly would revert to a syrupy green translucent liquid. Anyway after a few
days the firm setting blob effect didn't hang together but stayed a liquid, evolving a great pressure in the jar, which luckily I noticed the bowing
lid before something like this probably happened.
https://youtube.com/watch?v=oo5CB3WxGmU
[Edited on 7-12-2020 by Morgan]
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Morgan
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Another thought about the carbon in a hypothetical faulty thermos. If used for this, maybe it'd be possible to go higher than $88,000. Hypothetically,
perhaps a poorly welded seam in a Stanley steel thermos could develop a pinhole leak from a sudden cryogenic temperature shock. Then the vacuum would
draw in the lox.
"However, the Dewar flasks the LOX was stored in occasionally exploded, which was caused by iron impurities in the activated carbon serving as trace
gas absorbent in the insulation vacuum layer in the flask, which caused spontaneous ignition in case of LOX leak into the enclosed space."
https://en.wikipedia.org/wiki/Oxyliquit
[Edited on 25-12-2020 by Morgan]
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