Nice score.... but the oil is contaminated with anhydrous..?

[AcIdBuRn02ZTS]

Hey guys...

So a good friend of mine works for a local cold storage outfit and asked if I would be interested in a tote of waste oil. Of coarse I didn't turn him down.... and it was a large tote... 330gal.

So now the problem... the plant's refrigeration system uses Anhydrous Ammonia as the refrigerant. Some of the oil in the tank was oil from the large compressors which was contaminated. I've been letting the tank sit for the last few weeks and have been draining it off... The owner says that it will evaporate on its own if the tank is left open and in the sun...

This oil wont be touched for at least a year and it will be outside with a cover over the top of the tank... but the lid will be off to allow for ventilation. Think it'll be ok to use?

He claims the company that used to pickup their oil would test it and if the concentration was too high, it would have to sit a little longer and it would drop a good bit.

Anyways...
-Chris

 

[laserjock]

So the ammonia will evaporate over time. I don't know what the solubility is in oil, but I would bet you could extract it with water. The way you know it's done, you take a portion add about an equal amount of water, shake it up, let it settle and check the pH of the water. If it goes up, there's probably still ammonia dissolved. I'd let it set as long as you can because it should evaporate the majority off as I doubt the solubility in oil is terrific.

 

[jwalterus]

https://www.osha.gov/SLTC/etools/ammonia_refrigeration/ammonia/

 

[G. Mann]

Looks like agitation of the oil with a air bubble system would cause the ammonia to react with the air bubbles and be carried away with proper venting.

it's reactive with water.. but if you put water in the oil.. you have to take it out.. and it will be "ammonia water" so not good, in my book.

 

[laserjock]

Looks like agitation of the oil with a air bubble system would cause the ammonia to react with the air bubbles and be carried away with proper venting.

it's reactive with water.. but if you put water in the oil.. you have to take it out.. and it will be "ammonia water" so not good, in my book.

Ammonia produces ammonium hydroxide in water... well sorta... essentially it generates a basic solution. Ammonia in water is actually what most glass cleaners are. If the concentration is not real high (which presumably it wouldn't be after sitting a long while to vent the ammonia, much like chlorine setting out of tap water over time) danger factor would be pretty low.

100% correct in the fact that if you put the water in, you have to remove it. That's why I suggested the first test do an extraction and test the water layer. It takes VERY little ammonia to change the pH of water so if you see no change, the ammonia concentration in the oil is probably nil.

 

[laserjock]

The other thing you can do to 'degas' the oil is heat it gently. The ammonia has a MUCH lower boiling point than the oil. As long as it doesn't azeotrope with the oil (which I don't think it would) you could get rid of it that way down to extremely low levels.