Help Water into DNAx Membrane

[CraigAClark]

Thank's for all your advise
The Water temperature is 28°, i heared about this system to cool off the air temperature, but not easy for me to install, anyway,
I will follow your advise and try to do something before sending back the membrane to the manufacturer, if i have no result!

I would be very skeptical of a manufacturer that has already told you that heating the air wasn't necessary. Especially if they provided you with a system that depended solely on a "pneumatic dryer" to handle suspended moisture. That just proves they have no clue. There are those that will sell you anything just to make money. Reminds me of applied physics and how it varies depending on your location on earth! How in S.E. Asia, a Bauer 059183 Triplex filter will last 50 hours on a 3.5 cfm compressor when the maximum process capacity is only 3200 cuft in optimum conditions.

 

[c.fletcher]

I would be very skeptical of a manufacturer that has already told you that heating the air wasn't necessary. Especially if they provided you with a system that depended solely on a "pneumatic dryer" to handle suspended moisture. That just proves they have no clue. There are those that will sell you anything just to make money. Reminds me of applied physics and how it varies depending on your location on earth! How in S.E. Asia, a Bauer 059183 Triplex filter will last 50 hours on a 3.5 cfm compressor when the maximum process capacity is only 3200 cuft in optimum conditions.

Agree with you Craig
I will ask again the guy who sold me this membrane
but it seems there is 2 types of membrane, hold style and "new" style... and the new one wouldn't need to heat the air!?
but i will ask him again
Temperature of my air supply is probably around 40°C (110°F) after the cooler/Dryer!
apparently good! are you agree??
thank you again for your help

 

[Wookie]

Agree with you Craig
I will ask again the guy who sold me this membrane
but it seems there is 2 types of membrane, hold style and "new" style... and the new one wouldn't need to heat the air!?
but i will ask him again
Temperature of my air supply is probably around 40°C (110°F) after the cooler/Dryer!
apparently good! are you agree??
thank you again for your help

A purpose of the heater is drive up the temperature of the air, thereby keeping the air temperature above the dewpoint. Another purpose is to regulate the inlet temperature of the air into the membrane, because a fluctuating inlet temperature will give a fluctuating nitrox percentage. There are no "new style" and "old style", membranes aren't made for making nitrox, they were invented for making nitrogen, which they do very well. If someone sold you a membrane and told you you didn't need a heater, it's because he didn't want to lose the sale, not because you don't need a heater. You need a heater. if for no other reason, to keep the air above the dew point, and stop getting water in your membrane. That's how this whole conversation got started.

 

[CraigAClark]

Agree with you Craig
I will ask again the guy who sold me this membrane
but it seems there is 2 types of membrane, hold style and "new" style... and the new one wouldn't need to heat the air!?
but i will ask him again
Temperature of my air supply is probably around 40°C (110°F) after the cooler/Dryer!
apparently good! are you agree??
thank you again for your help

Absolutely not! Your 110F air is more than likely at or near 100% relative humidity. That is the problem! The hotter the air the greater the capacity to hold suspended moisture. Think of it as a sponge that is saturated to the point where it doesn't drip any liquid. All the water is suspended in the sponge which is now at 100% relative humidity. The only way to get rid of more liquid is to squeeze the sponge. In essence, by dropping the air temp you are squeezing the sponge. The lower you drop the temp, the harder you are squeezing the sponge. You are still at 100% RH, but at a much lower temp. Now by heating the air, you are going to reduce the RH even further, achieving a level that will cause no ill effects to the membrane. Think how humid the air is where you are compared to the same temp air in the desert!

 

[c.fletcher]

A purpose of the heater is drive up the temperature of the air, thereby keeping the air temperature above the dewpoint. Another purpose is to regulate the inlet temperature of the air into the membrane, because a fluctuating inlet temperature will give a fluctuating nitrox percentage. There are no "new style" and "old style", membranes aren't made for making nitrox, they were invented for making nitrogen, which they do very well. If someone sold you a membrane and told you you didn't need a heater, it's because he didn't want to lose the sale, not because you don't need a heater. You need a heater. if for no other reason, to keep the air above the dew point, and stop getting water in your membrane. That's how this whole conversation got started.

Ok thank's for all your explanation
I will contact the manufacturer and ask them properly the way i should opperate

 

[Zodiacdiverdave]

If you want to continue using a membrane system without a drier unit then you may want to switch to banking high pressure air and use a reducing regulator to feed the Membrane. There are electrical DC heaters available to raise the heat.
If you need replacement membranes I have 2 used membranes available. Just PM me and we can discuse it.
Also, switch to Activated AL rather then Mole Sieve as a drier agent off your LP compressor.

Another thing is using a continious feed system and bottled O2. This is much better if you don't have AC power.

I agree with the others that moisture in the LP air system is the issue. You need to dry the air prior to reheating it and then send it to the membrane.

Good luck,
ZDD

 

[Wookie]

If you want to continue using a membrane system without a drier unit then you may want to switch to banking high pressure air and use a reducing regulator to feed the Membrane. There are electrical DC heaters available to raise the heat.
If you need replacement membranes I have 2 used membranes available. Just PM me and we can discuse it.
Also, switch to Activated AL rather then Mole Sieve as a drier agent off your LP compressor.

Another thing is using a continious feed system and bottled O2. This is much better if you don't have AC power.

I agree with the others that moisture in the LP air system is the issue. You need to dry the air prior to reheating it and then send it to the membrane.

Good luck,
ZDD

I have seen this done with very early nitrox membrane systems, exactly for this reason. The air in banked breathing systems is very dry. It is also extremely expensive, but it may be a solution for not having a heater. You'll have to run your Hi Pressure compressor approximately 4 times as long as you would your low pressure compressor to make the same amount of feed air to your membrane. That means you'll change the filters in your tower 4 times as often as you otherwise would. I think a DC heater would be easier to come up with....

 

[c.fletcher]

If you want to continue using a membrane system without a drier unit then you may want to switch to banking high pressure air and use a reducing regulator to feed the Membrane. There are electrical DC heaters available to raise the heat.
If you need replacement membranes I have 2 used membranes available. Just PM me and we can discuse it.
Also, switch to Activated AL rather then Mole Sieve as a drier agent off your LP compressor.

Another thing is using a continious feed system and bottled O2. This is much better if you don't have AC power.

I agree with the others that moisture in the LP air system is the issue. You need to dry the air prior to reheating it and then send it to the membrane.

Good luck,
ZDD

I had this system before, with 4 B50 HP feed with my HP Compressor, but as you said, i had to use 4 time my HP compressor so it's useless for me
and i also use NX Stick with B50 of O2, but i need lots of B50 for 6 weeks traveling south with 16 Pax... also not a option!

I will see if i can find DC heater working on LP compressor Batterie!??

 

[Wookie]

I had this system before, with 4 B50 HP feed with my HP Compressor, but as you said, i had to use 4 time my HP compressor so it's useless for me
and i also use NX Stick with B50 of O2, but i need lots of B50 for 6 weeks traveling south with 16 Pax... also not a option!

I will see if i can find DC heater working on LP compressor Batterie!??

You'll probably have to upgrade the dhoni engine alternator to 150 amp or so to keep the battery up, but getting a DC heater shouldn't be a problem.

 

[c.fletcher]

Do you have any advise on DC heater brand or web site where do buy or having info??
tx again