Centrifuge and filtering effects on additives

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Ok I have a bit of a different one;

Anyone know of any practical resources for determining how and when additives are forced out of oils by a centrifuge or filtering?

We use a straight cutting oil in machines cutting metal, the oil drips of the metal scrap and gets put back in the machine.

The cutting oil is normally a mineral oil (group III) with an inactive sulfur EP and some DiEster added.

Currently the oil gets filtered to 5micron and reused.

Over time the machine slide lubricant oil, a heavily iso68 with a tackifier and its own aw/ep additives, bleeds into the cutting oil.

I wanted to try to use a WMO centrifuge to remove the metal fines and any disolved sludges in the centrifuge... Rather than having them redeposit in the machine.

I heard murmurings of centrifuges even at 1000G's will pull out additives?

Our oil rep says 2micron is the limit for depth filtering, otherwise the EP will be removed.

Thanks guys
 
This is the definition of chasing one's tail....
Change it out once it starts to stink, even after filtering.
Otherwise, too many variables to have an intelligent discussion.
 
https://www.alfalaval.com/industrie...ube-oil-treatment/lube-oil-cleaning/faq/


Quoted answer from Alfa Laval:

" Q: Will the additives in the lube oil be destroyed with centrifugal separation?
A: No, the molecular alliance of the additives with the oil is stronger than the centrifugal force. "


I have an Alfa Laval Emmie, a 5000G, centrifugal separator. It's an amazing device and it will absolutely pull water, various common contaminates and bacteria from jet fuel with perfection. It can also bring aging gasoline back to life by removing the gums and varnishes. I tried it on used motor oil with poor results, (even when diluted with jet fuel) , despite the claims that it can effectively filter lube oil. It cannot pull carbon and soot out, as the density of carbon particulates is not sufficiently different from the motor oil. It removed some wear metals and water from used motor oil, but the soot remained entirely.

The centrifuge can only remove particulates and components that are more dense than the oil or fluid itself.
 
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The
Originally Posted by Imp4
This is the definition of chasing one's tail....
Change it out once it starts to stink, even after filtering.
Otherwise, too many variables to have an intelligent discussion.


The thing is in a cutting oil application the oil will be loaded with metal fines well before the oil goes bad, the oil will look brass or alum colored (depending on the material cut) even after settling for awhile, and it takes very little energy to get what does settle mixed up again.
 
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