Compressed air dryer

[dguzzi]

  What do you guys use for (cheap) airline water trap/drier?
  I'm running new plumbing and want to keep it dry inside.

[RinkRat II]

       Greetings dguzzi,
      what part of the country are you in? Makes a big difference if the humidity level is high.  For starters your tank is a great moisture removal device. Keep it drained DAILY.  The best for the money next step is to find a Filtered Centrifugal Separator and plumb it between your tank and the system. If you have an old small refrigerator you can coil up 8-10 feet of copper and plumb it to remove any further moisture down to about 40 degrees.  Next step is filtration for oil and contaminates depending what your using the air for.  More questions, just ask.

      Paul B   

[Kiwi_Roy]

Its not the sort of thing you are looking for but you might find it interesting, before I retired I worked on some prototype filters used to separate water from air, they worked with a material were the holes were too fine to pass air but water could pass through readily.
I used to buy air dryers for Instrument Air systems, I think they were rated at -40 degrees.
Heres an another unusual one based on a membrane exchange, the water molecules pass through from damp air to exchange with dry air.
https://duckduckgo.com/?q=nephanol+air+dryer&t=osx&iax=images&ia=images
if you are only dealing with a small volume the lab suppliers sell nephanol dryers that look like a piece of coaxial tube.
A desiccant type
https://secure.drierite.com/catalog3/page5.cfm

[pete mcgee]

Roy,
How does that work?
I can follow air going through and water not, ie gortex, but the other way around?
Someones using physics I dont understand ( not hard I know).

[Kiwi_Roy]

Roy,
How does that work?
I can follow air going through and water not, ie gortex, but the other way around?
Someones using physics I dont understand ( not hard I know).

I know, it doesn't seem possible, I barely scraped through high school but I worked with some brilliant process engineers, all I had to do wa figure out the controls.
They say BS can baffle brains any day, they never did catch me out LOL
Apparently the air molecule is larger than a water one.

[StuCorpe]

I'm with Pete, I can understand air going through (as it has an atomic radius of about 1.4-1.5 angstroms) and water will not (atomic radius of about 2.75 angstroms).  I can't understand the reverse happening.  Can you point me to something that might explain it?

[Kiwi_Roy]

I'm with Pete, I can understand air going through (as it has an atomic radius of about 1.4-1.5 angstroms) and water will not (atomic radius of about 2.75 angstroms).  I can't understand the reverse happening.  Can you point me to something that might explain it?

I can't explain it, I'm not a process engineer but I can't explain the Nephanol membrane either, there the water wicks through the membrane to the dryer low pressure air on the outside.
These filters where like socks inside a large tank, the water passed through the sock and out the middle.
I know the company I worked for had a patent on it so it must have been something special.

[harry h]

What I did was run 8' pipe in a zig zag configuration totaling about 24-30'.  I get zero water in the main trap or in the trap on my blasting cabinet. I also have a drain that I empty along with draining the tank after a day or two.  The only thing I would suggest is using black pipe instead.  I already had most of the materials which are galvanized.

[aklawok]

 Have had good results with RPB Radex brand filtration systems, we use them on dive compressors for breathable air .

[Rebochi]

   A second receiver installed in a cool place works or a vertical section of larger diameter pipe, to slow the velocity with a drain on the bottom and the outlet mounted high with the inlet mounted low and installed in a cool place will work without costing a fortune. The cooler the receiver/vertical column the more moisture will condense out of it.

[larrys]

Need to keep the air cool enough so the water separator will work. The manual for the Sharpe separator/regulator on my compressor recommends 25' of pipe between the compressor and the separator. I cheated by using a 3' section of commercial hydronic heat element as an air cooler. I placed it on the compressor so the fan in the compressor sheave blows air through it. I drilled and tapped in a 1/8"NPT drain fitting in one end so it can be drained. As others here have already stated, drain the tank and the separator bowl often.
Larry

[cliffrod]

99% of my stone carving is done with pneumatic hammers. getting a sleeve or face full of dirty moisture is not fun, but getting any such oily crap on a $$$$ sculpture can be a fatal error.

I have air plumbed in galvanized iron pipe with multiple vertical riser sections that each have a length of pipe below the lower T with ball valve at bottom to drain.  All my pipe is installed on a slight incline as well, directing moisture to these drop-out traps.  Dirt cheap and effective. Adding a horizontal section at bottom helps direct the water/air where you want it to go when you drain it.  If I keep them drained and keep the tank drained, I have little to no moisture issues even here in SC during the humid part of the year.  Adding a store-bought drier or more elaborate system (I like rodekyll's ball bearing water trap) would be wise if I was painting but for normal use, my problems are solved.

Keeping your tank drained EVERY day is the first step.  If you're not doing that, the results are to be expected.  It' amazing how few people keep their tank drained and then complain about moisture issues or how their small water trap is no good.

Edit-pics of water traps and drains













More common sense is to not attach any tap or outlet into your iron air line that is configured to function as a water trap.  If it can hold water, it will.   Point it up.

[tcunnien]

In my garage I installed a Camair CT30 desiccant air dryer. I have a media blaster and various paint guns along with the usual air tools. When the desiccant bag get saturated with moisture I remove it and place it in the oven at around 175 degrees and it dries it out. I have had for quite awhile now and am still on my original desiccant bag. I have included a picture that I posted earlier of my Triumph you can see the dryer on the left hand side of the picture.