A theoretical analysis of the pulse column was made using a stage-wise approach to the problem. The column was assumed to be divided into discrete stages, each stage having been defined as that part of the column between two adjacent perforated plates. The cyclic reversal of flow which is characteristic of the pulse column permitted more material balance equations to be written than for a simple countercurrent extractor.
Burkhart, Lawrence E. and Fahien, R. W., "Pulse column design" (1958). Ames Laboratory ISC Technical Reports. 212.