Compressing Hydrogen

[giovyledzep]

How would you go about blending Oxygen and Hydrogen? Assuming the final blend results in an Oxygen concentration that is below the safety limit for explosions (say 3% O2 97% H2), would it be safe to just setup a Stick and run the blend into a compressor, making sure the system is properly purged? Would you necessarily need a special oxygen clean compressor? Would the hazards be similar to Nitrox blending?

 

[KenGordon]

How would you go about blending Oxygen and Hydrogen? Assuming the final blend results in an Oxygen concentration that is below the safety limit for explosions (say 3% O2 97% H2), would it be safe to just setup a Stick and run the blend into a compressor, making sure the system is properly purged? Would you necessarily need a special oxygen clean compressor? Would the hazards be similar to Nitrox blending?

Surely it would be easier to assess the risk of a partial pressure blend? Put the hydrogen in first so you never have an explosive mix.

Either way, I’d not stand in the same building

 

[JMBL]

My 2 cents about it :

A : something about the 1st guy who ever dived hydrox

B : about hydrox

C : a video about Hydra VIII an extensive testing of hydrox diving during the mid 80's, conducted by Comex off the coast of Marseille. There's something about gas mixing around 12:00 in a room satured by nitrogen to prevent explosion of the diving mixture

My conclusion : please don't ever try !

 

[Storker]

Either way, I’d not stand in the same building

In the immortal words of Derek Lowe:

“Oh, no you don’t,” is the common reaction of most chemists to that proposal, “. . .not unless I’m at least a mile away, two miles if I’m downwind.”

https://blogs.sciencemag.org/pipeli...3/things_i_wont_work_with_dioxygen_difluoride

 

[broncobowsher]

For compressing I would be looking at a used CNG compressor. The design is for compressing natural gas to very high pressures without leaking any to the outside nor blowing itself up.

Now the blending part, please leave notes of what you tried a long way from where you are doing it. that way if something goes wrong we have some idea of what to never try again.

 

[tbone1004]

first, don't do it, it's really dangerous. IF you're going to do it, please use something designed for boosting hydrogen. Haskel does make boosters designed for compressing hydrogen for reference

 

[Rooster59]

 

[Lorenzoid]

Oh the humanity!

 

[iain/hsm]

If your planning on breathing hydrogen in a breathing mixture first you need to verify the method of the hydrogen production. Current available high pressure hydrogen gas has two very dangerous compounds associated with its production that are fine for the main applications for hydrogen but are extremely dangerous from a point of breathing them at depth.

Second none of the major gas producers and suppliers are in a position to advise you on the safe PPM limits of these two compounds or indeed the ppm levels within the hydrogen gas, because unless your breathing it there is really no reason to analyse for them in the first place.

Third Neither are any hyperbaric doctors I am aware of either.

Its a catch 22. You need the background experience and knowledge to even begin to know where to begin
and those who do know are all ex offshore diving engineers and they dont get a look in now a days because anything to do with diving on this forum is controlled by medical moderators. And all your hard work submittd photo's and answers will be deleted as it was when we last discussed IWR on this forum.

So I dont see this topic getting much above a dead swedish dude that has a medal named after him and folk posting pictures of some balloon on fire.

If you want sub 250 MSW for my money neon would be an easier option to kick off with either way we wont get chance to discuss it fully either as we are already way past Tekdive 2020 or other some such forum bandwidth limit.
PS if you need to know how to compress hydrogen safety try the compressor section located in the backwater of these forum pages no one bothers looking for us down that deep. Iain

 

[Doppler]

Blending by molar mass... hydrogen is approximately 2.014 grams per mole while for oxygen it's approximately 15.9994.