Help Water into DNAx Membrane

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c.fletcher

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Location
Maldives/France
Hi everyone
I have a problem with my DNAx "LW" membrane
I use Low pressure compressor, with filters and drainer
and i found some water into the 'in" inlet membrane
The poucentage is still good, but very low volume of NX
Before i could feed 2 Mariner 320 and now only 1 mariner 240!
My question is
Can i flow air in the "out" inlet to flow water out?
Can i open the membrane to dry it?
anyone have the "drawing" of this membrane
I'm in Maldives and no service here!
I Have to do everything by myself....
Thank you in advance for your help
For sure i will find "specialiste" in Scubaboard users
GD
Chris
 
Hi Chris

That is not good news. The membranes are highly susceptible to clogging the "tubes" from oil or grime. If you put pure, clean water into it, then you may be able to run Nitrogen backwards through the membrane to "flush" it out. but, I really don't think that water is your problem.

The optimum temperature for feeder air is 110 F and I think that running for several hours at that temp should have dried out any water than may have collected in there.

No ... I am afraid you have probably introduced oil into your membrane chamber. visualize your membrane as a bundle of "straws" that are sized so that the N2 molecules are small enough to go through but the air molecules aren't. By taking the N2 out of the air, it increases the percentage of O2 in the mix.

If any moisture, dirt or oil will clog up those "straws" and not allow N2 to flow. That is probably what has happened. I have had a couple guys tell me that they have a friend that knows a guy who worked for a fellow that was able to clean membranes with some magical solution. There really is no fix. But to be sure, you should contact the manufacturer of your system to see what they say.

membrane.jpg
 
Hi Chris

That is not good news. The membranes are highly susceptible to clogging the "tubes" from oil or grime. If you put pure, clean water into it, then you may be able to run Nitrogen backwards through the membrane to "flush" it out. but, I really don't think that water is your problem.

The optimum temperature for feeder air is 110 F and I think that running for several hours at that temp should have dried out any water than may have collected in there.

No ... I am afraid you have probably introduced oil into your membrane chamber. visualize your membrane as a bundle of "straws" that are sized so that the N2 molecules are small enough to go through but the air molecules aren't. By taking the N2 out of the air, it increases the percentage of O2 in the mix.

If any moisture, dirt or oil will clog up those "straws" and not allow N2 to flow. That is probably what has happened. I have had a couple guys tell me that they have a friend that knows a guy who worked for a fellow that was able to clean membranes with some magical solution. There really is no fix. But to be sure, you should contact the manufacturer of your system to see what they say.

View attachment 148436

Thank's a lot rcontrera
sound i'm not lucky!!
I will try to flow clean air in out outlet to try to get out the water, or dirt!
and if i have the same result... do you think i can "open" it?? to see inside the membrane?
Thank's again
GD Chris
 
Do not put air into the Nitrogen outlet. Air will not go through the "straws" and you will destroy your membrane. If you want to try to back flow through the membrane, use filtered Nitrogen only. As for taking it apart, go ahead ... AFTER you have ordered the replacement.;)
 
Do not put air into the Nitrogen outlet. Air will not go through the "straws" and you will destroy your membrane. If you want to try to back flow through the membrane, use filtered Nitrogen only. As for taking it apart, go ahead ... AFTER you have ordered the replacement.;)

Hi, i work with Chris and don't understand how oil arrived inside the membrane. Installation seemed to be simple:
- one LP compressor 1500 l /min 10 bars
- after it we put one pneumatic cooler with a permanent water and oil oflow
- then one cyclonic filter, one micronic filter, one sub micronic filter and a huge carbon and molecular seve filter.
Does it seems ok for you regarding the filtration?
 
You would think that would be good assuming all the filtration is before the air hits the membrane heater. How often do you change the filters? When you found the moisture in the inlet, what did the filter tower look like when you inspected it?
 
You would think that would be good assuming all the filtration is before the air hits the membrane heater. How often do you change the filters? When you found the moisture in the inlet, what did the filter tower look like when you inspected it?

Filters are nearly new, few hours less than 100h
The Notice said about the carbon filter "valid for 1000h" from LW manufacture
I didn't open the carbon filter because it's sealed from factory! but look's like "good"
Few drops of water in the tower, and not more!?
look's like strange don't you think!?
 
The Notice said about the carbon filter "valid for 1000h" from LW manufacture

Well, there is part of the problem. 1000 hours on your system is over 30000 cubic feet of air! There are NO filters that are that big in the Nitrox biz. I don't know who LW is but we use either Norgren or Hankinson breathing air three stage LP filters to feed our membranes.

So, if you found moisture in your final filter, your system has failed.

Hankison-20-pack.png
 
You probably right, the system has failed
the LW carbon filter is a Huge one,
I don't understand also why this happened!?
We do use also the three stage LP filters to feed our membrane, plus LW carbon filter, than membrane
anyway thank's a lot for your help
so for you NO air into the Nitrogen outlet to flow off the water!
I will follow your advise
last chance is to taking it apart...
 
As Rcontrera said, taking the membrane apart will destroy it. You do that at your peril. When you say that your carbon media filter is "huge", what do you mean? Mine is a meter tall and a third of a meter in diameter and it holds 20 lbs of carbon media. It lasts a thousand hours only. I change the media every year. When I say a thousand hours, that's a thousand hours on the low pressure compressor, not the high pressure compressor.

If you are going to take something apart it needs to be that carbon tower. See if there is any oily residue on the outlet. Check with a white cotton ball or qtip or something white so you'll see if there is any carbon or oil breaking through. I disagree with Rcontrera that water isn't your culprit, I've had that problem before.
 

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