moisture in the compressed air ?

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I don’t get any moisture at all in either my scba bottle or my pcp’s.

Why? Because I use 4 dessicant filters from my 3 shop compressors, those 3 compressors, each with 12 inch fans to cool them and a 30/70 run/rest ratio to keep them cooler.Then this filtered air is then directed into a storage tank which cools it, however that tank never collects water, then route the filtered air to my Altaros Booster which runs cold to the touch. The 4th filter inside the booster never gets moisture to it.

Now those little disposable hot running compressors, using the tampon filters, which are saturated long before your gun is filled are simply a bad,2 pronged joke on the user. First punch line if that joke is the saturated filters, 2nd is they are disposable and most often no practical warrantee or parts. I always drain the entire system of air and store with relief valves open, then run them open for a while when starting up.

Regards,

Roachcreek_
 
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Roachcreek said:
I don’t get any moisture at all in either my scba bottle or my pcp’s.

Why? Because I use 4 dessicant filters from my 3 shop compressors, those 3 compressors, each with 12 inch fans to cool them and a 30/70 run/rest ratio to keep them cooler.Then this filtered air is then directed into a storage tank which cookies it, however that tank never collects water, then route the filtered air to my Altaros Booster which runs cold to the touch. The 4th filter inside the booster never gets moisture to it.

Now those little disposable hot running compressors, using the tampon filters, which are saturated long before your gun is filled are simply a bad,2 pronged joke on the user. First punch line if that joke is the saturated filters, 2nd is they are disposable and most often no practical warrantee or parts. I always drain the entire system of air and store with relief valves open, then run them open for a while when starting up.

Regards,

Roachcreek_
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I have seen your posts , impressive set up , way too much time and space for me . depending on what the local supplier for nitro say's i am going that way .
 
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Hopefully you are going to a nitrogen supplier that actually fills the bottles so you eliminate some middle men
Nitrogen is the cheapest and most abundant gas that is produced buy the air separation process anyone trying to make theirs sound special and charging more than 20 bucks per hundred cubic feet go find their competitor.
 
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Problem you have with N2 is that your releasing it into our atmosphere, when the molecules combine with cow fart molecules, we will all doomed.;)

Yeah, I do love my Altaros system, but when I move to Asia I will probably need to peddle it. Right now I am looking at shipping it in balik bayan boxes, which is cheap $260.00 at this time to ship everything, it all depends on my eyesight at the time.

RC
 
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BlackICE said:
Assuming you don't have a siphon tube in your tank, wouldn't cooling your tank in a refrigerator and then purging some air get rid of any water that would be in liquid form at room temp?
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I suppose that could work to some degree. Maybe even bumping the tank downward while inverted (but not against valve). But, I think it’s unlikely you would get it all. Consider a cold glass of water on a humid day. Some moisture will condense into water on the outside of the glass and maybe form a droplet that rolls to the bottom, but largely, a lot of condensate will still be on exterior of the glass. Pretty sure the same thing would occur inside the SCBA.
 
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It’s the compression that is the problem more than temp. Think of a sponge that contains moisture. If you squeeze it really hard that water is coming out. That is what we do to air with our compressors. Now temp may play a big role in the amount of moisture a body of air can hold, however when you compress it to 200-300 bar it’s being squeezed out. This happens no matter where you live. An inline filter is always going to be a necessity.
 
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Roachcreek said:
Problem you have with N2 is that your releasing it into our atmosphere, when the molecules combine with cow fart molecules, we will all doomed.;)

Yeah, I do love my Altaros system, but when I move to Asia I will probably need to peddle it. Right now I am looking at shipping it in balik bayan boxes, which is cheap $260.00 at this time to ship everything, it all depends on my eyesight at the time.

RC
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OH MY ! nitro powered cow farts . (can you compress that for a gun ? )
 
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Roachcreek said:
Problem you have with N2 is that your releasing it into our atmosphere, when the molecules combine with cow fart molecules, we will all doomed.;)

Yeah, I do love my Altaros system, but when I move to Asia I will probably need to peddle it. Right now I am looking at shipping it in balik bayan boxes, which is cheap $260.00 at this time to ship everything, it all depends on my eyesight at the time.

RC
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moving to asia , my friend in Japan said laws are very strict no air or PB guns .
 
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If I am still able to think clearly and see enough to shoot, one of the first things I will do is contact my attorney in the Philippines to see what I need to do to get a import permit, then compare prices with a Airgun shop in Manila. But that is 2 years away and not so sure about how much of me will be left by then.

Right now I don’t even own a .177, so mostly pipe dreams.

RC
 
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Trucker3573 said:
It’s the compression that is the problem more than temp. Think of a sponge that contains moisture. If you squeeze it really hard that water is coming out. That is what we do to air with our compressors. Now temp may play a big role in the amount of moisture a body of air can hold, however when you compress it to 200-300 bar it’s being squeezed out. This happens no matter where you live. An inline filter is always going to be a necessity.
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I don't think it is accurate to think of compression as being more of a "problem" than temperature - they are both factors rather than problems, and since eventually the temperature will equalize to ambient we are left with pressure as the variable that changes the most. And the analogy to a sponge is not really a good one since it is all about the pressure (or volume) and nothing about the temperature. Water is not being "squeezed out" of the air as we compress it; the compressed air (at a constant temperature) is unable to contain the same volume of water as a vapor, so the molecules end up combining into a liquid (it is a function of hydrogen bonding taking over in the energy balance, not squeezing).

But here is the thing: what Beerthief originally proposed in his first post WOULD work. All the statements to the contrary are simply wrong . . .

If you can cool the air charge that leaves the compressor to below ambient for the tank, and trap that liquid water from getting into the tank, then the tank would have no condensed water in it. The RH in the tank would be close to 100%, but that is fine - it is close to it even after passing the air through a good desiccant dryer (such is the nature of high pressure air - it simply can't hold much water vapor).

Not to dissuade Beertheif from going with Nitrogen, if I were wanting to do this I would get a good sized coalescing filter and put it in a bucket filled with ice water. I'd also hook up a system of one way valves and vents so that I could pressurize the coalescing filter and leave it that way, and I would run the compressor in short intervals to better manage the heat (venting near the compressor for easy starting). So I'd bring it up to tank pressure and shut it off so that the filter could cool down all the way, then run it for a bit and give it some time off to further cool. Repeat as needed to get a filled tank . . .

Doing this would guarantee that the air going into the tank would be below ambient dew point at pressure, thus there would be no liquid water in the tank.
 
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You need NO coalescing filter if you feed the compressor Nothing but pure dri Nitrogen, thats all that goes into the gun NO CHANCE of water in it.
Have you ever driven down the road and seen a tank chained to a pole and a hose going up to a big black Cable thats a trunk line and the phone companies use it to dri out the cable as condensation occurs from temp changes and rainy weather and the nitrogen dries out the moisture as long as there is an exit for the gas and moisture. the moisture causes cros talk between the wire pairs and comms go to crap
 
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karl_h said:
Re-read, talking about taking moisture out of air PRE compressor, and besides, breathing air cannot be made with just moisture separators. A moisture separator is only taking out water that is condensed already. You need a molecular sieve after to take out water vapor after the seperator(s). Unless you call a molecular sieve a moisture separator, which it is not.
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Karl,

I think it is you that need to re-read. The OP talks about cooling air before it enters a gun or tank. I guess that could be pre-compressor but I think it much more naturally reads as after compression and prior to introducing it to the gun. Many of us, including specifically me, do this in a way now. The air lines exiting my compressor go upward to two stages of filtration and after that they go down to my SCBA tank. I get significant condensation at the vent of the YH which I let out every 5 minutes of run time. That water condensed as the air traveled through the lines and ran back to the compesser where it gets vented so it doesn't have to be filtered. If the lines lowered the air temperature further it would condense even more of the moisture that separated due to the compression. But I believe filtration is still necessary, I can just change my color changing desicant beads less often. I don't have to change them much, now, however. I check them after every couple runs but they don't need changed more than once or twice a year. The little white filter of the YH gets changed every run, however.

Jim
 
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Since Nitrogen does not carry water vapor like oxygen you don't need to remove moisture from it - there is none. As long as it's pure. But the valves necessary to use nitrogen are expensive. And you need a reasonably priced and located source - including if you ever travel.

Adding dessicant filtration to the output of a YH (or other small compressor) is not hard or expensive. If you use color changing dessicant you can check to be sure it is not getting saturated during your runs. I think sometimes we overthink things. I use the stock white filter the YH came with first partially because it also catches oil that is in the output. I don't know what the oil would do to dessicant but I doubt it would be a good thing.

Compressing air reduces it's ability to carry moisture. But increasing temperature increases that ability. The compressor does both. But the temperature will fall and when it does, moisture will come out. I think venting away as much as is easily possible makes a lot of sense but a final filter using dessicant is still appropriate IMHO. I also think it makes a lot of sense to put a one way valve on the output of the dessicant containing filter.

If I had any big bores I would probably want a more complex air supply setup. But I don't and don't plan any. One 45 minute SCBA tank a month is about all the air I need and my YH is a good inexpensive way to get it.
 
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elwoodblues said:
The valves for nitrogen use are NOT expensive unless you are trying to use 4500 or 6000 psi bottles thats not what we are doing here
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and now after talking to AirGas (my local place ) i find out they provide breathable air to the Medical community same as dive shops , possibly better filtered .SO i can get nice clean dry air .
 
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