NITROX Membrane systems recommendations.

[ediverudt]

I am looking at installing a membrane on my Bauer K18 (6000 psi 21 CFM 5 stage)
After looking around it looks like there are a few people that make something like this.
What I am looking to do is a portable compressor on a trailer so all of the air storage systems seem a little to impractical sense my system will be set up to do hot fills on 10 80cf tanks at the same time.

I am looking for people that have any good ideas for setting up a membrane for a portable system and anyone that has a good alternative for the 220 V heaters used on most of these systems.

Obviously I could uses a generator for the 220 and run a 220 low pressure compressor to feed the membrane as well. Has anyone done this and how well dose it work?

 

[CraigAClark]

Are you planning on building your own system or are you looking to purchase a system?
I won't waste your time with a recommendation if it is the former.

Craig

 

[Zodiacdiverdave]

I am looking at installing a membrane on my Bauer K18 (6000 psi 21 CFM 5 stage)
After looking around it looks like there are a few people that make something like this.
What I am looking to do is a portable compressor on a trailer so all of the air storage systems seem a little to impractical sense my system will be set up to do hot fills on 10 80cf tanks at the same time.

I am looking for people that have any good ideas for setting up a membrane for a portable system and anyone that has a good alternative for the 220 V heaters used on most of these systems.

Obviously I could uses a generator for the 220 and run a 220 low pressure compressor to feed the membrane as well. Has anyone done this and how well dose it work?

It seems that you want to use a portable mambrane system to feed other compressors as well as your K-18, or is your K-18 a portable unit?
The LP comressor you will require would have to have an output of 45cfm @ 175psi to feed your large HP compressor, so if you plan on using a generator to drive this you would require a 25KVA, 3 phase unit at mimimum just for the compressor.

I use to sell membrane systems for Undersea Breathing Systems but later switched over to Nuvair due to better delivery and responce times. I don't know if Bill at USB has sorted out his difficulties he was having, I wish him the best.

Anyway back to the membrane system, If you plan on doing alot of Nitrox then yes plan on a membrane but if it is just from time to time say less then 40 tanks a week then I would recommend using a continious blending system, the startup is going to be alot cheaper for you.

If you do decide to get a membrane system you really shoud get an electric unit and bank the gas then use a booster to charge the tanks while on at the dive site.
You can also mimimize the startup cost by getting a larger air bank and using the stored HP air to feed the membrane, that's what I do.
ZDD
ZDD

 

[Wookie]

My LP compressor makes 45 cfm@175 PSI and it barely makes 36% to feed a 5406 Mako at 13 CFM. That K18 is a beast and will need a tremendous amount of LP air. I would size a 20 hP screw for that job. If you want to trailer mount the whole thing, plan on a 30 kw genset for enough power for the whole portable installation. If you're gonna think big, stand by to open the old wallet.

 

[rcontrera]

A portable diesel powered unit is gonna hit your wallet HARD (about $28k) but, you should be able to get about 37-38%.

 

[Zodiacdiverdave]

My LP compressor makes 45 cfm@175 PSI and it barely makes 36% to feed a 5406 Mako at 13 CFM. That K18 is a beast and will need a tremendous amount of LP air. I would size a 20 hP screw for that job. If you want to trailer mount the whole thing, plan on a 30 kw genset for enough power for the whole portable installation. If you're gonna think big, stand by to open the old wallet.

Wookie, I think that you may have another issue going on if you have 45cfm @175-psi of LP air available for your membrane. Assuming everything is sized right for your system you will be loosing aprox. 25% of the feed air as nitrogen which should leave you with just under 34cfm available for your 13cfm hp compressor.
When sizing a LP compressor for a system I would always double the cfm requirment for the HP unit and add a little more.
The unit that you have should have 2 membranes that are either 5 in. in dia. or 2.5 depending on the manufacturer of the membrane. There is also an 8 in.dia. x 5 ft membrane out there as well. If you have one of those you should be able to make plenty of nitrox for your compressor.
If your system is sized correctly I would be checking for leaks.
ZDD

 

[CraigAClark]

I spoke with Bob (Nitro Bob) of Nitrox Solutions today about your request. He says, prepare to spend big bucks! This was a face to face discussion, as we are working on a project together. Water cooling is a must, for both lp and hp units. IMO, if you are using air cooled equipment, you are asking for trouble.


Craig

 

[ediverudt]

The system will be mounted on a trailer and I already have the compressor and other parts it is running off of a Gas v twin command 15 motor. The plan is to make this system completely portable as I commonly dive and take large groups of students over 4 hrs from my home and am planing on doing only Nitrox no air at all.

 

[Zodiacdiverdave]

The system will be mounted on a trailer and I already have the compressor and other parts it is running off of a Gas v twin command 15 motor. The plan is to make this system completely portable as I commonly dive and take large groups of students over 4 hrs from my home and am planing on doing only Nitrox no air at all.

If you want to go that way then look at a portable LP compressor/ membrane unit. Talk to Glen @ Nuvair about what you want and he can build you a unit.
ZDD

 

[Wookie]

Wookie, I think that you may have another issue going on if you have 45cfm @175-psi of LP air available for your membrane. Assuming everything is sized right for your system you will be loosing aprox. 25% of the feed air as nitrogen which should leave you with just under 34cfm available for your 13cfm hp compressor.
When sizing a LP compressor for a system I would always double the cfm requirment for the HP unit and add a little more.
The unit that you have should have 2 membranes that are either 5 in. in dia. or 2.5 depending on the manufacturer of the membrane. There is also an 8 in.dia. x 5 ft membrane out there as well. If you have one of those you should be able to make plenty of nitrox for your compressor.
If your system is sized correctly I would be checking for leaks.
ZDD

Went back and checked specs. My IR 2545 10 hP makes 35 cfm@175 PSI. My bad.