Quince
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Compressor dryers?
How do air dryers for air compressors work? Not all the ones I've seen use desiccant materials, so I can't figure out how the others work.
\"One of the surest signs of Conrad\'s genius is that women dislike his books.\" --George Orwell
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not_important
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OK, limited knowledge but I'll tell what I know. Just stop the waterboarding, please.
Refrigerated dries work like refrigerators (!) - chill the air so as to condense water in it. May have several sections where one is in 'defrost' mode
if the air is being dried to a low dew point. Can be used before or after the compressor.
Membrane driers push the air through porous tubes while venting some of the air to flow around the outside of the tubes and out to the open air.
Moisture is ducked through the walls of the tubes and evaporates into the vented air. I believe these have to dump some of the heat of compression so
that liquid water forms on the tube walls, where it is wicked on through; evaporation cools the tubes and helps with further condensation.
There's several types that use desiccants and regenerate them on the fly. In one type the hot compressed air is used to heat the saturated desiccant.
This can be indirect heating, with a secondary air stream flowing through the desiccant to vent. Alternatively the hot air flows through the used
desiccant, then through a heat exchanger that cools the air stream enough for much of the water to drop out. In either case the air then flows through
the other, active desiccant bed for final drying.
In another type pressure swing is used. The freshly compressed air flows though active desiccant beds, while used bed have a stream of low
(atmospheric) pressure air run through them to remove the absorbed water. Sort of like vacuum drying, except the vacuum is normal pressure, the drying
stage is running at 10X or more about that.
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12AX7
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It doesn't take much as the compression raises the boiling point of water quite a bit, causing it to condense. It also heats up the air, so a
condensor needs to remove quite a bit of heat. The water is then drained through a spit valve, so to speak. Dessicants are also used, and
regenerated at STP or dehydrated in an oven.
So what's with your sig, mmh?
Tim
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Quince
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| Quote: | Originally posted by 12AX7
So what's with your sig, mmh?
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Just replying to what you said about me in the microwave drill thread: "IrC, not a bad title suggestion given the nature of our present protagonist."
I figure two eyes for one is a better way to live than an eye for an eye.
[Edited on 26-10-2006 by Quince]
\"One of the surest signs of Conrad\'s genius is that women dislike his books.\" --George Orwell
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Mr. Wizard
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Are you asking about the dryers on air conditioner compressors, or about the condensate traps on air compressors?
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Quince
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The latter. Do you have any details on their internal geometry? I'm thinking of DIYing one for my compressor.
[Edited on 27-10-2006 by Quince]
\"One of the surest signs of Conrad\'s genius is that women dislike his books.\" --George Orwell
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Mr. Wizard
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The water formed in a compressor is due to the rise in pressure and the subsequent cooling after the air leaves the compressor. The partial pressure
of the water is the same as it always is at ambient temperature. This of course leaves the air oversaturated with water and it condenses out along the
tanks, pipes, and hoses as it cools. Some of it remains in a fog or mist, as does some of the compressor oil. The condensate traps for tools usually
just have a screen or loose filter to facilitate the coalition of the fog into droplets. The ones used on paint sprayer applications may use active
chemical or dessicants, because of the higher need for pure air. Don't forget to drain the compressor tank, as that's where the most water collects
and the most rusting takes place. I don't have much more than that.
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Twospoons
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Why would you DIY one? They are very cheap.
The ones I have are essentially a block of sintered bronze powder, intended to force the fine mist to form large droplets, which then fall to the
bottom of the enclosing plastic bowl. A simple plastic shield stops spray getting into the outlet at the top.
Most have a little drain valve at the bottom for emptying. Fancy ones have a float operated valve so draining is automatic.
You can also buy a single unit that has both regulator and mist trap - this being a lot cheaper than buying the two separate items. Have a look at
the SMC website for examples.
Helicopter: "helico" -> spiral, "pter" -> with wings
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Quince
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Shit, doesn't matter now... the bitch I was going to buy the compressor from sold it to someone else cause I was 1 hr late in calling back...
\"One of the surest signs of Conrad\'s genius is that women dislike his books.\" --George Orwell
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12AX7
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| Quote: | Originally posted by Quince
Just replying to what you said about me in the microwave drill thread: "IrC, not a bad title suggestion given the nature of our present protagonist."
I figure two eyes for one is a better way to live than an eye for an eye.
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Ah, an emotional response to a statement of fact, I'm not suprised with you.
Tim
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Texium
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Thread Moved
19-11-2023 at 11:30 |
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