how temperature and humidity affects a compressor filter

[telitalabella]

Hi, i am about to buy a new compressor for a little dive shop that i want to open in Honduras, this will be my first compressor, i don't know much about compressors, my question is in Honduras is 80's and 90's all year around, i don't know the humidity, i just want to know how long a bauer p-31 or a p-41 cartridge will last there. thank you

 

[rjack321]

Ambient humidity has almost no impact on filter life. The gas entering the filter will be at 100% humidity no matter what. Its a function of all the compression.

Temperature will have a huge impact. But this will be installation specific. If the compressor is in an air conditioned room it will last longer than if its outside. Worst possible installation in a small unventilated space the filter will barely work at all.

At 20C ambient (cool), 30C separator outlet temp (pretty cool) and 300bar (which is quite high and hence the filter is more efficient) the p31 and p41 will filter 500cubic meters and 1000 cubic meters respectively.
BAUER COMPRESSORS - Products - Air Treatment & Testing - P-Filter System

For a typical tropical installation about 250 cubic meters and 500 cubic meters is realistic performance. This can be improved with air conditioning and air chillers.

I'd highly recommend good quality synthetic oil, multiple triplex (13x/AC/hopcalite) filters, the Securus monitoring system to ensure your filters are not overworked and allowing hydrocarbons into the gas you're selling. And lastly a CO monitor. For tropical installations with high temperatures partial combustion of oil generating CO is a life threatening risk that you must be extra vigilent about.

 

[dannobee]

Look here. Page 41 in the service manual (49 if you used the reader's page number)

http://www.bauer-kompressoren.de/pdf/produkte/betreiberhandbuch_e.pdf

Temperature has a huge effect because higher temperature air holds more moisture. If you could get your air from the north slope of Alaska, your filters would last a LONG time because air that cold holds no moisture. Literally.

 

[SDAnderson]

A good separator/coalescer is worth its weight in gold. Running the compressor overnight (cooler) as much as possible also helps.

 

[telitalabella]

thank you very much for your imputs, i learn a lot from it

 

[h90]

Ambient humidity has almost no impact on filter life. The gas entering the filter will be at 100% humidity no matter what. Its a function of all the compression.

Temperature will have a huge impact. But this will be installation specific. If the compressor is in an air conditioned room it will last longer than if its outside. Worst possible installation in a small unventilated space the filter will barely work at all.

At 20C ambient (cool), 30C separator outlet temp (pretty cool) and 300bar (which is quite high and hence the filter is more efficient) the p31 and p41 will filter 500cubic meters and 1000 cubic meters respectively.
BAUER COMPRESSORS - Products - Air Treatment & Testing - P-Filter System

For a typical tropical installation about 250 cubic meters and 500 cubic meters is realistic performance. This can be improved with air conditioning and air chillers.

I'd highly recommend good quality synthetic oil, multiple triplex (13x/AC/hopcalite) filters, the Securus monitoring system to ensure your filters are not overworked and allowing hydrocarbons into the gas you're selling. And lastly a CO monitor. For tropical installations with high temperatures partial combustion of oil generating CO is a life threatening risk that you must be extra vigilent about.

Do I get it right?
Whatever moisture is in the air, it will be far over 100 % at 300 bar.
Everything over 100 % will be condense in the separator and the rest will be absorb in the filter.
So actually (if I am right) neither the ambient moisture nor the temperature is important. Really important is the temperature in the condenser (or separator, don't know how it is called in English) and the size of it and the pressure in it (100 % moisture at 200 bar are 50 % at 100 bar).
But the ambient temperature direct influence the condenser temperature.
Am I right, or did I misunderstood something?

So if I could cool down the air in or before the separator the filter would last much longer? Right?

 

[dannobee]

Do I get it right?
Whatever moisture is in the air, it will be far over 100 % at 300 bar.
Everything over 100 % will be condense in the separator and the rest will be absorb in the filter.
So actually (if I am right) neither the ambient moisture nor the temperature is important. Really important is the temperature in the condenser (or separator, don't know how it is called in English) and the size of it and the pressure in it (100 % moisture at 200 bar are 50 % at 100 bar).
But the ambient temperature direct influence the condenser temperature.
Am I right, or did I misunderstood something?

So if I could cool down the air in or before the separator the filter would last much longer? Right?

The ambient temperature and humidity play important roles because the number of water molecules in the air increases as each rise. That water will fall out of suspension and be eliminated by either the coalescer/separator or through the filter's molecular sieve. The desiccant gets saturated and can no longer "filter" or trap the moisture.

But, yes, chilling/cooling the cooling tubes will help eliminate the moisture before the filter(s), making them last longer.

 

[h90]

The ambient temperature and humidity play important roles because the number of water molecules in the air increases as each rise. That water will fall out of suspension and be eliminated by either the coalescer/separator or through the filter's molecular sieve. The desiccant gets saturated and can no longer "filter" or trap the moisture.

But, yes, chilling/cooling the cooling tubes will help eliminate the moisture before the filter(s), making them last longer.

hmm got it.....
No one ever got the idea to actively cool the out coming air?

 

[dannobee]

hmm got it.....
No one ever got the idea to actively cool the out coming air?

Of course. That is why they are coils and not just pipes going to the next stage. But getting it down to something actually cold has its problems, too. Since the gas is still saturated, the water will freeze in the pipe if your cooling medium is below freezing.

 

[rjack321]

Do I get it right?
Whatever moisture is in the air, it will be far over 100 % at 300 bar.
Everything over 100 % will be condense in the separator and the rest will be absorb in the filter.
So actually (if I am right) neither the ambient moisture nor the temperature is important. Really important is the temperature in the condenser (or separator, don't know how it is called in English) and the size of it and the pressure in it (100 % moisture at 200 bar are 50 % at 100 bar).
But the ambient temperature direct influence the condenser temperature.
Am I right, or did I misunderstood something?

So if I could cool down the air in or before the separator the filter would last much longer? Right?

Very close.
No matter what all the compression will cause the humidity to rise to 100%. With really really dry outside air the condensor will just drain a little less.

100% humidity will go into the filter no matter what.

The cooler the outside air the cooler the compressor will run and the cooler that 100% humidity air going into the filter will be. Cool air holds less moisture than hot so the filter won't have to work as hard and will last longer. The oil will last longer too, as well as pretty much everything else on/in the compressor that cooler you can run it.