Periodic cycling of plate columns: Mass transfer with nonideal liquid draining

Mathematical modeling of a periodically cycled plate column has been completed by using a liquid bypass model to describe nonideal liquid draining. A numerical solution over a wide range of parameters provides a closed envelope of feasible solutions. A region of this envelope encloses favorable operating values of the parameters, while the other region is unfavorable. Measurements of the parameters for nonideal liquid draining in a 600 mm diameter column fitted with sieve plates lead to predictions of only small improvements in separation performance. Modifications to the column intervals are required to move the parameters into a more favorable position in the solution envelope.