Sciencemadness Discussion Board

Bubbles in condenser water

mr.crow - 13-3-2012 at 11:50

I keep getting air bubbles in my condenser. Bubbles completely cover the inner tube and ruins the heat transfer, so annoying! It does this with tap water as well as recirculated water.

How can I avoid this?

bfesser - 13-3-2012 at 12:19

<ul><li>Periodically tap the condenser gently with a rubber stopper on a pencil.</li><li>Be sure the water flows in the lowwer barb and out the upper barb.</li><li>Abruptly shut off and restart the flow from the source. Sometimes it'll dislodge air bubbles.</li></ul>

I suppose degassing your water would be feasible, but likely a wasted effort. If it bothers you that much, create a closed heat-exchange loop. Use a copper coil in a bucket of ice to remove heat from the water before recirculating it to the condenser. Add a T in there somewhere with a balloon or pipette bulb zip-tied on&mdash;something to reduce pressure fluctuation. Boil the water to degass it, then fill the closed system.

[edit]
Give the inside of the condenser (the surfaces which contact cooling water) a good chemical cleaning. In my experience, bubbles will adhere less to meticulously clean glass surfaces.

[Edited on 3/13/12 by bfesser]

mr.crow - 14-3-2012 at 08:46

Thanks for the advice!

Would a West condenser be any better due to higher water velocity?

I think the water is just exceptionally bubbly. Even the recirculating reservoir gets covered in bubbles after a while

Bot0nist - 14-3-2012 at 10:33

Touch the condenser with a source of vibrations. I think peach even said he used a sex toy because of the variable speeds and softness. :o

Arthur Dent - 15-3-2012 at 03:38

Quote: Originally posted by Bot0nist  
Touch the condenser with a source of vibrations. I think peach even said he used a sex toy because of the variable speeds and softness. :o


:o LOL! Gives a whole new meaning to "degassing your condenser", does it? Thanks for the indelibile image burned in my mind!!!

Robert

Refinery - 1-6-2020 at 11:46

I countered this issue a while ago. The condenser was completely covered with air bubbles, to the extent that it was just enough to condense acetone vapors.

What surfactants could be added to the coolant water to reduce bubble formation? I could easily run it through submerged coil to keep it cool.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4705484/

I remember seeing these surfactants (Dodecyls and oleates) in some laundry detergents, am I right? They're supposed to contain defoamers and other non-corroding substances that should not harm pumps etc. So adding a scoop of a detergent could be a start?

EDIT: On a quick test, two samples were heated in glass beakers. The laundry powder one developed noticeably lesser bubbles and they were smaller in size. Pure water beaker was quickly covered with bubbles. No accurate measurements were made, this was just more of a "is water moist" - type of test.

[Edited on 1-6-2020 by Refinery]

Fyndium - 7-9-2020 at 14:03

Few drops of ordinary dishwashing liquid soap appears to get rid of the bubbles. Just tested it out.