Extraction dispersion band, height

The terms "number of stages N" and "height equivalent to a theoretical plate HETP" are used in chromatography however, their meanings are quite different in comparison to continuously operated countercurrent columns (absorption, extraction, rectification). Here, the column length or height must be sufficient to draw apart the bands of components or fractions. This reqnires favorable eqnUibria, certain retardation differences, and limited axial dispersion. 

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