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Vacuum processing for removing perfume.

Vacuum processing for removing perfume.

Vacuum processing for removing perfume.

(OP)
I have a small blower that has been polluted with powder with fragrance in it,(we believe baby power).  It has been disassembled and washed with industrial detergent and hot water. Even the encased blower control board.  It was then reassembled and run.  An obvious perfume odor is still present and polluting the exhaust air.

It was suggested there are only so many molecules of fragrance available, so if they're all lost thru attrition the detectable odor will be gone also.  On that basis the unit was run full blast 24/7 for 60 days.  There has been no detectable odor reduction!

We have a vacuum chamber and are wondering if an extended session in it would cause the remaining odorant to out gas, or boil off, or if this would be unlikely to work?

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Vacuum processing for removing perfume.

Itsmoked,

Might work.  Would help if you could warm the blower whilst it is in the vac. chamber.  Also, you should alternate an hour or so in vacuum with an air backfill, then operate blower or otherwise clean or "rinse" all the surfaces, and then repeat both steps.  

We found in trying to clean hydrazine residuals out of control valves that the vacuum tended to pull residuals out of crevices to the surface, which could then be cleaned away by rinsing.  Repeating the process (alternating warm vacuum with water rinse and air/nitrogen purge ) gave an order of magnitude faster rate of cleaning compared to any single process by itself.

Even just vacuum with multiple air backfills can help - the idea is that under high vacuum, the contaminant molecules that you are trying to purge aren't mobilized to go anywhere.  Backfilling with air will hopefully stir these molecules, and the subsequent vacuum draw will tend to remove these mixed-in molecules with the air being drawn.  Every fill/evacuate cycle should theoretically reduce the contaminant concentration by an order of magnitude or so.

RE: Vacuum processing for removing perfume.

(OP)
Thanks btrueblood!  I will use the "air wash" method.  Makes sense that if there are only a few air molecules floating about there is no good transfer mechanism available.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Vacuum processing for removing perfume.

Don't get discouraged as it will take sevral cycles to remove the offending molecules. We have a process where we want "0" O2 in a system and it takes 7 Nitrogen wash cycles to get the O2 to non dectectable levels. On cold days we apply a little heat to the vessel to kick it up a notch.
 

RE: Vacuum processing for removing perfume.

(OP)
Thanks unclesyd.

I shall not get discouraged!  On that info I will probably put the whole thing under computer control and let it "cycle" until nirvana is achieved.  My vessel is a piece of 18" dia. heavily crazed Plexiglas pipe so I think I will be avoiding any heat. infinity

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Vacuum processing for removing perfume.

(OP)
Now that the blower is in the chamber in a vacuum, it just dawned on me..

How long do I keep it 'down' on each cycle?

Seconds?
Minutes?
Hours?

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Vacuum processing for removing perfume.

We allowed our equipment to set 30 minutes in both the vacuum and pressure stage.  

Since we were after O2 with its excellent diffusibility we were told by the scientist that our O2 diffusion was almost instantaneous, a matter of seconds for each part of the cycle was all that was needed to reach equilibrium with the residual O2 after each cycle.
 

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