The HETP values for the TRP column are consistent with a previous
study27 that used similar random packing for
nitrogen-argon separation. HETP values for the PTL column are lower,
while those for the AMPH column are the lowest (3.2 cm for nitrogen,
3.3 cm for argon). Thus, the AMPH column is the most effective of the
three. This increase in separation efficiency with the same column
height is an example of process intensification through improvement of
the gas liquid interface in the column.
Figure 9 shows how the result for the AMPH column (3.2 cm) is consistent
with HETP values from previous PNNL MCD studies. In general, HETP values
increase with mass flux.