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Pressure drop through bubble cap column

Pressure drop through bubble cap column

Pressure drop through bubble cap column

(OP)
I am looking to buy a used column, 1m x 14m bubble cap 42 caps, 52 trays.

I have no history of this column etc, is it possible to calculate pressure drop through this column or can it be only done from actual data.

All I am after is a ball park figure.

RE: Pressure drop through bubble cap column

(OP)
Like I said I am after a rough figure.

Our current column is 1m x 12m 34 actual plates 20 theoretical. i.e 60% effeicent.

Taking this 60% effency as a ballpark figure, can I assume that my new one of 52 plates has 31 theoretical?

Rough figure needed!

RE: Pressure drop through bubble cap column

You can get a rough estimate for pressure drop knowing the tray weir height.  Typically 2 or 3 inches.  52 tray times 2 inches is 104 inches of whatever the liquid on the trays density.  If its water, then .43 psi/foot of water or 104 inches dived by 12  is 9.  9 times .43 is 4 psi.  Plus about 2 psi for the gas flow.  6 psi would be a minimum drop.

Tray effiency is a design variable for the trays and is quite complex.  Typical ranges are 40% to 80%, so 60% isn't an unreasonable value.

RE: Pressure drop through bubble cap column

If my recaller is working we used 2 mm pressure drop per tray as a standard on our vacuum bubble cap columns. We were separating Diamines and Diamines/water. I know that all the weir heights were set a 2". We kept the 2 mm/tray to keep the base temperature down to prevent product degradation.

RE: Pressure drop through bubble cap column

(OP)
Thanks to you both for the above information, very good.

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