DIY EAN Membrane build

[Ty Hamby]

Only 1x 250cf? Just get a couple more, they are vastly cheaper than a membrane system.

How deeply are you drawing that bank down? I have 2x 4500, 2x 3600, 3x 2200 bottles for about the same volume as you. The 4500s never get below about 3200, the 3600s I draw down to perhaps 2500, and the 2200s go the lowest to 1500 ish. To top all that off is less than 250cf of O2.

I have only filled the bank once with ean32. I have 4) 444cf 4500 cylinders and 2) dual rated 5250PSI/7000PSI ASME cylinders. All filled once to EAN32 @4500psi. After doing it I discovered a leak in the ASME cylinders and ended up venting those 2 to replace the o'rings in the end bushings. I then just mixed in straight air reducing the o2 over time. Last I tested the bank it is sitting at ean23. My bank is split up it 3 banks of 2 cylinders each pumped to 4500. After going through 2.5 K cylinders of o2 I decided to look at other options. This whole compressor(s) sticks and cylinder storage is all new to me. Learning a bunch from you guys. I am now realizing once I am full, I would not need as much o2 to maintain as I did for filling from atmosphere (actually filled after fresh hydro on the 444cf cylinders.

There is also a less standard and much cheaper option. You can fab up a ghettobrane (patent pending) system by feeding prebuilt oxygen concentrators into a nitrox stick feeding your compressor. These are powered by an auxiliary relay circuit triggered on by the compressor contactor.

Ghettobrane. Now you're speaking my language. I have 2 independent circuits in my shop. I have the main feed ( newly installed) which is 50A 220 1ph. It runs my lathe, mill, lights, outlets, and 10hp 5406 compressor. The compressor consumes 99% of that 50A breaker. When running the HP compressor I have to turn off the overhead lights or I pop the breaker. The old original 15amp drop to the shop is mostly unused now. Ill have to look at the current draw of the concentrators. Stacking up concentrators into a stick may be the ticket. If I don't have enough AC power I may be forced to go down the bank o2 route. Which also sounds fun. Compressing high o2 content does scare me a bit. Will look at your other threads on this subject.

 

[TMurrr]

There is also a less standard and much cheaper option. You can fab up a ghettobrane (patent pending) system by feeding prebuilt oxygen concentrators into a nitrox stick feeding your compressor. These are powered by an auxiliary relay circuit triggered on by the compressor contactor.

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I've been reading quite a bit about the homefill setups and definitely am interested in one...

Could you also hook up multiple concentrators to the same homefill compressor for faster O2 fills? CC @tbone1004

 

[rjack321]

I've been reading quite a bit about the homefill setups and definitely am interested in one...

Could you also hook up multiple concentrators to the same homefill compressor for faster O2 fills? CC @tbone1004

That is exactly what @Tracy 's system is doing. The pump itself is just super slow (100 liter per hour) so you are looking at ~12 hours to fill a 40 with o2 from empty. More concentrators can't change that rate since they just feed the compressor.

 

[TMurrr]

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That is exactly what @Tracy 's system is doing. The pump itself is just super slow (100 liter per hour) so you are looking at ~12 hours to fill a 40 with o2 from empty. More concentrators can't change that rate since they just feed the compressor.

~12 hours to fill an AL40 to ~2k psi or so, right

 

[Tracy]

~

~12 hours to fill an AL40 to ~2k psi or so, right

A homefill with a 5lpm concentrator does about that.

 

[TMurrr]

A homefill with a 5lpm concentrator does about that.

Would a 10LPM concentrator effectively 1/2 the fill time? Or are we still limited by the capacity of the Homefill compressor

 

[Tracy]

Would a 10LPM concentrator effectively 1/2 the fill time? Or are we still limited by the capacity of the Homefill compressor

Wouldn't change a thing. The homefill is the limiting factor. If you are looking for speed, buy bottled oxygen. Homefills and ultrafills for for convenience, they aren't going to do anything quickly.