Oxygen booster explosion: be careful!

***Beanie*** · 22nd February 2008, 11:51

Quote: (Originally Posted by Northern Monkey)

I have used many of these one way valves myself, with no problems.

I spoke to Colin at Undersea and all the one way valves are supplied oxygen clean and he has never heard of any problems.

One suggestion is may be the one way valve may have been put into the system the wrong way round. Oxygen becomes unstable above 350 Bar.

I would imagine that the space between booster and valve is small and if in the wrong way any boosting would rapidly raise pressure and temperature.

PeteS · 24th February 2008, 19:28

Quote: (Originally Posted by nigelh)

I've heard this elsewhere but can anybody point me to same words?

All attempts at googling for it end up with me getting sidetracked into some fascinating stuff on astrophysics, super-conductors and para-magnetism but nothing on oxygen under pressure.

What does it do? Polymerise?

I read it in the instructions that came with my Haskel. Something like "Boosting oxygen above 346 bar is not recommended..." They never did explain why, just "don't do it, ok!"

What pressure does it become liquid at?

cool_hardware52 · 24th February 2008, 19:51

Quote: (Originally Posted by Northern Monkey)

Oxygen becomes unstable above 350 Bar.

Not exactly stable below 350 bar either........

cool_hardware52 · 24th February 2008, 19:55

Quote: (Originally Posted by PeteS)

What pressure does it become liquid at?

The boiling point will be a function of the pressure and temperature.

You aren't going to boost your way to a liquid state, you need very low temperatures also.

Tobin

teomannaskali · 25th February 2008, 03:53

What if you had access to liquid oxygen. Could you just pour that in to the tank?

If completely full with liquid how many bars would that rise up to when it reaches room temperature I wonder.

raymondone · 2nd April 2008, 09:51

[]

if your been boosting for 10 years,then your a cool crazy italian!!

raymondone · 2nd April 2008, 09:54

[

doctor deep, you crazy italian keep boosting love your style

raymondone · 2nd April 2008, 10:00

[
handling oxygen regardles,of any brand of booster pump is potentially dangerous.

AD_ward9 · 2nd April 2008, 10:54

Thank you for posting.

We have just used the video with our engineering team, as a reminder. Makes for good training material.

Iain supplied a nice little booster for 350bar O2 for bomb testing of O2 parts, so this is especially relevant as a reminder. It is besides us, as I post, and a the outside fire inspector is also here, wandering about our labs ...

Alex

jaap · 4th April 2008, 14:47

Quote: (Originally Posted by teomannaskali)

What if you had access to liquid oxygen. Could you just pour that in to the tank?

If completely full with liquid how many bars would that rise up to when it reaches room temperature I wonder.

Ok this gets rather funky.

Liquid O2 expands something 850 times its volume at 1 bar, 15 Celsius). I got that from Air Liquide Gas Encyclopaedia.

But if you filled a vessle completely with LOX you would not get 850 bar when the gas has evaporated and the vessle has reached room temperature.

This is because the compressibility factor of the gas becomes very important at these pressures.

The charts I have are not so detailed but the closest compressibility value I have for O2 is: 1,66 at 1000 bar at 300 K (27 Celsius). That is also from Air Liquide Gas Encyclopaedia, but a printed more detailed version that I don't think is freely avalible online.

So if we do a very rough and probably rather incorrect guesstimate from the above compressibility factor and say that it is ~1,5 at 850 bar O2 for the same temp. That means that O2 at 850 bar and ~300 K only holds a factor of 1/1,5 as many moles of O2 as the ideal gas law would predict. Since we have a fixed number of moles in our case it implies that the pressure would have to be approximately that much higher (in our case).

So the pressure would be something like 850x1,5 = ~1275 bar!

Remember, the value is far from exact but the pressure should be something like that and definately higher than 850 bar.

22nd February 2008, 11:51	#41 (permalink)
*Beanie* give a man an inch....... Current Rebreather/s: Inspiration Classic Other Rebreather/s: Inspiration Vision Join Date: Jan 2005 Location: In da house! yeah baby! Posts: 3,177	Re: Oxygen booster explosion: be careful! Quote: (Originally Posted by Northern Monkey) I have used many of these one way valves myself, with no problems. I spoke to Colin at Undersea and all the one way valves are supplied oxygen clean and he has never heard of any problems. One suggestion is may be the one way valve may have been put into the system the wrong way round. Oxygen becomes unstable above 350 Bar. I would imagine that the space between booster and valve is small and if in the wrong way any boosting would rapidly raise pressure and temperature. __________________ Beanie Gallery Admin & Library Assistant. www.outlawdivers.org.uk www.beandiving.co.uk www.beanengineering.co.uk
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24th February 2008, 19:28	#42 (permalink)
PeteS Consent Issued! Current Rebreather/s: Inspiration Classic Inspiration Vision Other Rebreather/s: Join Date: Jun 2005 Location: New Zealand Posts: 533	Re: Oxygen booster explosion: be careful! Quote: (Originally Posted by nigelh) I've heard this elsewhere but can anybody point me to same words? All attempts at googling for it end up with me getting sidetracked into some fascinating stuff on astrophysics, super-conductors and para-magnetism but nothing on oxygen under pressure. What does it do? Polymerise? I read it in the instructions that came with my Haskel. Something like "Boosting oxygen above 346 bar is not recommended..." They never did explain why, just "don't do it, ok!" What pressure does it become liquid at? __________________ Pete S. http://www.steggle.co.nz Every silver lining has a cloud
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24th February 2008, 19:51	#43 (permalink)
cool_hardware52 RebreatherWorld Sponsor Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Mar 2005 Location: SoCal USA Posts: 385	Re: Oxygen booster explosion: be careful! Quote: (Originally Posted by Northern Monkey) Oxygen becomes unstable above 350 Bar. Not exactly stable below 350 bar either........ __________________ www.deepseasupply.com
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24th February 2008, 19:55	#44 (permalink)
cool_hardware52 RebreatherWorld Sponsor Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Mar 2005 Location: SoCal USA Posts: 385	Re: Oxygen booster explosion: be careful! Quote: (Originally Posted by PeteS) What pressure does it become liquid at? The boiling point will be a function of the pressure and temperature. You aren't going to boost your way to a liquid state, you need very low temperatures also. Tobin __________________ www.deepseasupply.com
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25th February 2008, 03:53	#45 (permalink)
teomannaskali Custom Title Allowed! Current Rebreather/s: Home Build Other Rebreather/s: Not Bought Yet Home Build Join Date: Feb 2006 Location: Istanbul TR Posts: 385	Re: Oxygen booster explosion: be careful! What if you had access to liquid oxygen. Could you just pour that in to the tank? If completely full with liquid how many bars would that rise up to when it reaches room temperature I wonder.
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2nd April 2008, 09:51	#46 (permalink)
raymondone New Member Current Rebreather/s: Other SCR Other Rebreather/s: Other SCR Join Date: Nov 2007 Location: whitsundays Posts: 6	Re: Oxygen booster explosion: be careful! [] if your been boosting for 10 years,then your a cool crazy italian!!
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2nd April 2008, 09:54	#47 (permalink)
raymondone New Member Current Rebreather/s: Other SCR Other Rebreather/s: Other SCR Join Date: Nov 2007 Location: whitsundays Posts: 6	Re: Oxygen booster explosion: be careful! [ doctor deep, you crazy italian keep boosting love your style
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2nd April 2008, 10:00	#48 (permalink)
raymondone New Member Current Rebreather/s: Other SCR Other Rebreather/s: Other SCR Join Date: Nov 2007 Location: whitsundays Posts: 6	Re: Oxygen booster explosion: be careful! [ handling oxygen regardles,of any brand of booster pump is potentially dangerous.
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2nd April 2008, 10:54	#49 (permalink)
AD_ward9 So much more to learn Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Jun 2005 Location: Scotland Posts: 1,868	Re: Oxygen booster explosion: be careful! Thank you for posting. We have just used the video with our engineering team, as a reminder. Makes for good training material. Iain supplied a nice little booster for 350bar O2 for bomb testing of O2 parts, so this is especially relevant as a reminder. It is besides us, as I post, and a the outside fire inspector is also here, wandering about our labs ... Alex
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4th April 2008, 14:47	#50 (permalink)
jaap Normal people worry me Current Rebreather/s: Classic Kiss Other CCR RB80 / Clone Ray Other SCR Home Build Other Rebreather/s: Other CCR RB80 / Clone Ray Other SCR Home Build Join Date: Jun 2005 Location: Stockholm Sweden Posts: 453	Re: Oxygen booster explosion: be careful! Quote: (Originally Posted by teomannaskali) What if you had access to liquid oxygen. Could you just pour that in to the tank? If completely full with liquid how many bars would that rise up to when it reaches room temperature I wonder. Ok this gets rather funky. Liquid O2 expands something 850 times its volume at 1 bar, 15 Celsius). I got that from Air Liquide Gas Encyclopaedia. But if you filled a vessle completely with LOX you would not get 850 bar when the gas has evaporated and the vessle has reached room temperature. This is because the compressibility factor of the gas becomes very important at these pressures. The charts I have are not so detailed but the closest compressibility value I have for O2 is: 1,66 at 1000 bar at 300 K (27 Celsius). That is also from Air Liquide Gas Encyclopaedia, but a printed more detailed version that I don't think is freely avalible online. So if we do a very rough and probably rather incorrect guesstimate from the above compressibility factor and say that it is ~1,5 at 850 bar O2 for the same temp. That means that O2 at 850 bar and ~300 K only holds a factor of 1/1,5 as many moles of O2 as the ideal gas law would predict. Since we have a fixed number of moles in our case it implies that the pressure would have to be approximately that much higher (in our case). So the pressure would be something like 850x1,5 = ~1275 bar! Remember, the value is far from exact but the pressure should be something like that and definately higher than 850 bar. __________________ My initials: JAAP
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