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[mjpotts]

For one of my lab classes we are supposed to collect data on a packed tower that we have and scale that up to a much larger gas flowrate. I am away of the generalized pressure drop correlation and how to use that. What type of data should I be collecting from the test packed tower in our lab?

[siretb]

Get on each section (below feed and above feed if you have only one feed), or calculate
The liquid rate in moles/hours
The vapor rate in moles/hour
The vapor density and the liquid density
The temperatures (including reflux temperature)
The pressure drop
The pressure at top of column, or at condenser
The diameter of the tower and the kind of internal (type and nominal size)
It would be intersting to actually see where the flooding takes place. (you need pressure drop, and vapor & liquid rates for that).
On a small lab column be careful about subcooling on the reflux.

And check how the specific data you have fits on the generalized charts.

When you scale up, you will probably want to change the packing size. If so you will need to adjust the specific vapor rate (you will probably, then, have selected a more capacitive but less efficient packing). Then you will want to select an operating point that is at the same percentage of flooding (actual). Typically 60-70% of flooding is a good choice. 80% is too much.