Countercurrent transfer processes in the non-steady state

Countercurrent mass and heat-transfer operations are analyzed mathematically, taking into account column capacity, and a general solution is obtained which enables the course of non-steady conditions to be followed quantitatively for a wide class of processes. Absorption and extraction, continuous distillation and batch distillation, are treated in detail, and illustrative examples are provided of the behaviour of a typical heat exchanger and of a typical batch distillation process.