rate of vaporization of oil when temperature and vapor presure is know

[CharlesAlbert]

Is there an empirical formula that will estimate vapor loss of a mineral oil when the vapor pressure at a given temperature is known. I have a problem at a rolling mill
where mineral oil is applied by drip or spray onto the sheet and need to calculate the vapor loss to establish a VOM loss to atmosphere.

Chuck

chuck798081@aol.com

 

[Latexman]

Where's Beychok when you need him?

CharlesAlbert, I think you referring to evaporation from a non-boiling pool of liquid? Here's a couple links that may help you:

http://www.air-dispersion.com/usource.html

http://www.air-dispersion.com/usource.html#Non-Boiling Liquid Pool

You'll have to look around and see what's closest to what you are doing. This site is a good start!

Good luck,
Latexman

 

[mbeychok]

Latexman:

The methods for calculating the evaporation from a non-boiling liquid pool that are on my website (to which you referred Chales Albert) are for pools of liquid and for pools which are not being heated.

I don't think that dripping or spraying oil on metal sheets will form a pool (with a discrete thickness) nor am I sure that the oil is not being applied to hot metal sheets to provide cooling. In other words, I am not sure that the methods on my website apply to this case.

Milton Beychok
(Contact me at www.air-dispersion.com)

 

[Latexman]

mbeychok,

Agreed. CharlesAlbert gave no details or data. Unless someone brings forth knowledge that exactly matches what CharlesAlbert is doing, he's destined to search for something close enough to what he's doing, or develop his own. In both cases, he should do some research on what is available. That's why I referred him to your site. My response should have been more descriptive.

CharlesAlbert,

Again, "You'll have to look around and see what's closest to what you are doing. This site is a good start!" Further, it's not a perfect match to what you are doing, so you cannot take the equations and "plug and chug". Learn from it, and research the internet, periodicals, etc. to see if you can find exactly what you are looking for. Google (and other search engines) is your friend! I suspect using keywords from your industry (roller mill, sheet metal, etc.) and those related to the environment area you are looking at (VOM, VOC, evaporation, etc.) are your best bet for relevancy. If not successful, you may have to develop something.

Good luck,
Latexman

 

[sshep]

I don't really know how these type operations work (i.e. if the sprayed oil is recycled, etc) but these seem like reasonable alternatives:

Is it not possible to calculate the losses directly from the amount of make-up oil used, or by difference from the amount used vs that collected for disposal, as a film on the product sheet, or other accountable destination? If you can't account for the material it is likely ending up in the air.

Alternatively can air sampling and air flow measurements be used to obtain a real measurement of VOM's emitted?

These are just suggestions since any diffusion or VLE based calculations are likely to be in considerable error especially if no data about the air circulation across the equipment is used. Any results will need to be reality checked against an overall material balance or some other actual data. -sshep