Has Anyone Tested Shorter But Larger Diameter Packed Column?

[Salt Must Flow]

I know people say that you go tall for purity and larger diameter for higher take-off rate. People also say that the rule of thumb is the height of the column should be approx 20x the column diameter.

I'm curious for instance if anyone has tested a 4" column with 3' of packing (sized for a 3" column) rather than the traditional 3" column with 5'-6' of appropriately sized packing?

A 4" column has twice the volume of a 3" column. So a 4" column approx half the height contains the same volume of packing as a 3" column that's twice the height. I'd like to test filling a 3' tall segment of 4" column filled with packing that's sized for a 3" column, see if it will operate at the same power input and same take-off rate as a 3" column that's 5'-6' tall.

What would be the potential benefit of doing such a thing? A lot of people just don't have the ceiling height for a 3" reflux column. In the future, if additional height becomes available, it would be very economical and easy to add another 3' segment of column and up-size the packing to upgrade to a 4" reflux column with optimal 6' of packing.

I set my 4" VM up on top of a 15.5 keg boiler with a 3' tall column and the total height is 7' 6". That's relatively short and most any situation could accommodate this height.