Air dryer pellets

[twarren]

I have an air dryer from Princess Auto (Canada's version of HF). The dryer calls for pellets to be replaced every six months. How does one know when to replace pellets?
I have a package of pellets about six years old but never used, are they any good?

Pellets: http://www.princessauto.com/en/detail/air-dryer-pellets/A-p8506206e#tabs-3

Dryer: http://www.princessauto.com/en/detail/air-dryer/A-p8055757e

Thanks,
Warren............

 

[rburke65]

I would think they would be ok. What does the current pellets look like? Do they look the same?

 

[twarren]

I don't have any other pellets to compare. I purchased this air dryer a few years ago but never installed it till now.
I guess I can buy new pellets and compare with the ones I have.

Warren.....

 

[Grinder Bill]

The proper name for the pellets is "desiccant" and is the most common passive air drying method. Industrial air dryers that use desiccant also have a regeneration cycle that backflows dry air through the pellets thus removing moisture. Regeneration can also be achieved by heating the desiccant.

You may want to invest in a cheap re-useable desiccant moisture indicator.

http://blog.ecompressedair.com/bid/87224/How-to-Monitor-Desiccant-Quality

 

[StingRay]

Not a desiccant. These do not absorb moisture. It is a delesicant dryer. The pellets are a type of salt that effects the dew point. They actually dissolve to some degree over time. If any of you have ever made ice cream using ice and salt think of it being like that. You have to drain these daily as they will accumulate large amounts of liquid.

 

[keating]

The manual says it uses "Dessicant Silica Pellets"

 

[CNGsaves]

Wowsa . . . . looks like Princess Auto has developed a "low cost" dryer $59.99 which enables sale of HIGH COST "dryer pellets" at $39.99 for 2.46 lbs !!!

Typical dryer media is called "desiccant beads" so don't know what's the scoop of Princess Auto strange shaped "pellets" . . . likely their private label profit making initiative.

Desiccant beads generally in major categores:
a) decomposing (ie the drying process eats up the media)
[ THIS is the typical media used in air compression systems. ]
b) non-decomposing
These are typical for other uses like natural gas pipelines, etc. They come in either INDICATING or NON-INDICATING . . . which means they change colors when they absorb moisture.

OP . . . you'll likely have option of using either kind.

Here's example of more affordable media - - - $44.99 for 1 gallon or 7.4 lbs
http://www.amazon.com/dp/B00BXKBOYM/?tag=atomicindus08-20

The silica beads in long run would save you money also as they can be re-dried (like the indicating style above from Amazon). Just spread out beads on cookie sheet and put on BBQ grill low heat for a while.

Princess Auto is "selling you convenience" for the $40 every 6 mths . . . yeah right !!

 

[MacMcMacmac]

It is a deliquescent dryer. As stated above, the pellets absorb moisture and degenerate into a brine solution that is drained off. I have seen a few industrial sized units, but the ongoing cost of pellets and maintenance meant they weren't very popular. I remember seeing one tank with the entire bottom missing after it rusted out at the briny tide line inside the tank and blew off. That must have been a brown-trousers moment.

 

[keating]

These are typical for other uses like natural gas pipelines, etc. They come in either INDICATING or NON-INDICATING . . . which means they change colors when they absorb moisture.

OP . . . you'll likely have option of using either kind.

Here's example of more affordable media - - - $44.99 for 1 gallon or 7.4 lbs
http://www.amazon.com/dp/B00BXKBOYM/?tag=atomicindus08-20

If you're ok with non-indicating, a 10lb bucket of silica cat litter for $10 from the local pet mega-store, or walmart is the same thing.
Just shake the dust out and use a filter on the output.

 

[rodm1]

You could use the cat litter mixed with indicating beads I'm thinking of doing this.
http://www.walmart.com/ip/Mimi-Litter-Cat-Litter-4-lb-Cats/12018928

http://www.silicagelpackets.com/indicating-silica-gel-packets-and-indicator-cards/

 

[Notch1988]

The pellets sold by PA dissolve so if you they aren't a puddle at the bottom of your box then they are fine.

If you need more I'll sell you 5 pounds of the same pellets for $39 shipped to your door.

 

[pressure teck]

We use filters in a helium detector that look like the pics that Grinder Bill posted. We clean these filters by forceing dry air thru a pvc pipe set up. The filters will turn back blue if let the dry air run long enough. I maintain air on underground telephone cables.

 

[awdblazer]

i never used the pellets from princess
i just used the blue/pink descicant, that way i can reuse it

 

[pcmeiners]

"You could use the cat litter mixed with indicating beads I'm thinking of doing this." good idea.

No reason you can not regenerate the silica cat litter once the indicating beads change color, anyone who wants to pay ridiculous prices for silica, that is their prerogative.

 

[rodm1]

Is the indicating beads without Cobalt Chloride any good? I would rather buy a safer product if they are the same quality.

 

[rlitman]

Is the indicating beads without Cobalt Chloride any good? I would rather buy a safer product if they are the same quality.

The indicator (cobalt chloride) has just about no effect on the desiccant qualities. It's just there to help you know if they need recharging or not. I also would not worry about its toxicity. Just don't eat it, or regenerate the beads while spread out on your wife's cookie sheet in your kitchen oven (the indicator CAN contaminate your pan, and while it will not contaminate your oven, any oils from your compressor can smoke off the beads while regenerating, which can add unpleasant odors to your kitchen if baked there).
I keep an ancient flea-market purchased toaster oven in my shop which I use for this (mostly heating kydex sheets though).

Note that these beads (whether bought as silica gel desiccant, or silica gel kitty litter beads) can be regenerated in the oven at 325F for 3-5 hours (this works better in an electric oven than a gas one, because of the lower humidity inside). BUT they cannot be regenerated forever. The absorb oil in the air, which reduces their capacity for water over time.

 

[pcmeiners]

"I would rather buy a safer product if they are the same quality. "

Unless you are very susceptible to contact dermatitis or allergies there is little to to fear from cobalt chloride, Google cobalt chloride toxicity . I would not recommend sprinkling it on P&J sandwiches or on your favorite salad.