Medical Oxygen Generator for small volume Nitrox?

[CraigAClark]

CraigAClark Thanks for the lesson! So in your opinion is the 80% O2 we get down here safe for Nitrox blending? Granted it's safer from and explosion point! But do you think my fears of Co2 and Argon are justified or just down right silly?

Even if you just use draeger tubes (which I am suspect of their accuracy), get the gas tested. I would never give anyone a "go ahead" without an analysis. If the gas comes back with acceptable levels, then just do your calculation based on the 80%. I assume you already do this.

Regarding the Nuvair, I assume you already have an H.P. compressor? UBS used to run a system off of h.p. storage to supply the l.p. gas for their membrane. Obviously, that pressure had to be reduced to membrane pressure (max for a permea is 250, most of the technology used today, as with the Nuvair is 100 psi or less). Huge icing problem on the high-flow regulator. BTW, you don't need a nitrox stick with a membrane. I would suggest that you find a proportional thermostat to control the heater unit. they use a cheap non-proportional Johnson Controls model 419. Also, I will never sell a non-water cooled system again. Make sure, if you decide to go membrane or continuos blending, completely tear down your compressor, thoroughly clean it, rebuild it and use a suitable synthetic oil. Remember, there is absolutely no such thing as "breathing air" oil.

 

[Allan C Smith]

Wow this is starting to look like a lot of work! But thanks for all the Input. At the moment the shop I am affiliated with compressor is a older Bauer. That is full of some nasty Oil and was not planing on using it any way. The Idea for the Nitrox came out of wanting to bring it and some time after that Type R rebreathers to the island. I was planing on banking the Nitrox in my garage and selling it to the local shops and yachts. Based on the cost and complexity of the membrane system it looks like getting the local 02 analyzed and using a stick might be my best bet to get started. As far as compressors go I was gonna start small and then move up if demand grows. The Max-Air 35 or a Baby Bauer seemed like a good choice,I'll only have time to run a few hours a day any way. When I out grow the compressor it would be easy to sell off to a yacht. I'm sure there's some flaws here but I appreciate all your help.

 

[CraigAClark]

Wow this is starting to look like a lot of work! But thanks for all the Input. At the moment the shop I am affiliated with compressor is a older Bauer. That is full of some nasty Oil and was not planing on using it any way. The Idea for the Nitrox came out of wanting to bring it and some time after that Type R rebreathers to the island. I was planing on banking the Nitrox in my garage and selling it to the local shops and yachts. Based on the cost and complexity of the membrane system it looks like getting the local 02 analyzed and using a stick might be my best bet to get started. As far as compressors go I was gonna start small and then move up if demand grows. The Max-Air 35 or a Baby Bauer seemed like a good choice,I'll only have time to run a few hours a day any way. When I out grow the compressor it would be easy to sell off to a yacht. I'm sure there's some flaws here but I appreciate all your help.

When you use the word yacht, I start thinking 100+ meters and most all of the systems we built went on them.

 

[Allan C Smith]

When you use the word yacht, I start thinking 100+ meters and most all of the systems we built went on them.

Must be a discrepancy in regional lingo. Down here a yacht is any thing you can **** on and a yachty is any one that cruses around on one.

The idea is start small and do something no one else is down here. It's gonna take a lot of Discover Scuba Dives and getting to know the right guys in customs to bring some EAN to St. Vincent but it should be worth it. I got the bug, blending, for my mentor in Dominica and really miss having Nitrox down here. Glad to have SB as a resource.

 

[CraigAClark]

I hear you my friend. I taught scuba for 12 years and drove a cattle boat for 5 years as part of my job.

 

[NAM001]

In regards to the argon issues brought up. unless it is deco gas as adaquately covered, when making pp nitrox the argon level does not go up much. Ie. 40% nitrox would be 25% o2 with the 5% argon and 75% air would give you about 2% argon total. 30% should give you about 1.5% perhaps. Not a real significant increase in argon level.

 

[USMC]

I already had the OxyGen and Homefill II for my glass blowing hobby so I put together a new whip for PP blending. Here's a pic of my setup.

 

[Graeme Tolton]

Is that paintball yoke adapter built with o2 compatible materials?

 

[USMC]

Its all metal except for the gage. I cleaned it out and ran O2 through it at a low rate for 20 mins before putting it under pressure the first time.
I've done three PP fills with it so far without a problem. I know it only takes one but the chances of a fire or explosion even with non compatible materials is possible, but unlikely.

The old, "Do as I say not as I do"... I'm lucky to be alive, more so that I can still get around without a walker or wheelchair. I take some risks that many would not but the chances of someone besides myself getting hurt are min. If I blow up, I don't care! Sad but true...

 

[Graeme Tolton]

Its all metal except for the gage. I cleaned it out and ran O2 through it at a low rate for 20 mins before putting it under pressure the first time.

Magnesium is also metal.

Aluminum and steel are flammable under high pressure o2.
I've done three PP fills with it so far without a problem. I know it only takes one but the chances of a fire or explosion even with non compatible materials is possible, but unlikely.

I like by chrome plated brass.

The old, "Do as I say not as I do"... I'm lucky to be alive, more so that I can still get around without a walker or wheelchair. I take some risks that many would not but the chances of someone besides myself getting hurt are min. If I blow up, I don't care! Sad but true...

Sounds silly when you are gambling your own life/safety over not wanting to buy a $100 yoke adapter (new). I bought one of those hong kong paintball fillers, for the odd paintball tank of course on ebay. Having seen it's construction, i wouldnt dream of pp blending with it.

There is an oring inside that adapter, on the bushing that contacts the tank's j/ k valve oring. Not going to be viton or epdm.

---------- Post added April 23rd, 2013 at 11:12 PM ----------

. I take some risks that many would not but the chances of someone besides myself getting hurt are min. If I blow up, I don't care! Sad but true...

In principal, i agree with your mistakes are your problem. However, in reality when someone makes a dumbass mistake like blowing up their garage because they used some ebay pos fitting, it leads to more rules and regulations.

That being said , for the sake of the rest of the diving / home mixing community, dont cheap out on the basics.

Buy the oxygen hackers companion. It will guide you to some far safer ways to cheap out on pp whips. Worth every penny.