Perspectives: Plant InSites

Ease Measurement of Column Internal Flow

Opting for a pump instead of gravity to return liquid to a tower often makes sense

By Andrew Sloley, Contributing Editor

Last month, we looked at using a gravity-flow loop to measure liquid flow inside a column (“Get Some Inside Information[http://goo.gl/CTYvck]”). An often-attractive alternative uses a pump to return the total liquid draw taken from the column. The important engineering fundamentals of this system lie in the pump and control logic.

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