646. The steam stripping of taints from liquids: V. The basic design of cream deodorizing equipment

Extract

A comparison is made of the stripping characteristics of the types of plant studied in previous papers of the series. The effects of alterations to the type of plant, the number of vessels used or a change in processing conditions on the volatile flavour components are illustrated by calculations for solutes having equilibrium coefficients m of 2, 10 and 50. For design purposes a hypothetical taint of m=10 is used, the final taint concentration being set at 10% (of initial) for high-taint pastures and 25% for low-taint areas. Using the above hypothetical conditions, calculated steam-demand figures are shown to agree with known typical steam-demand values. The use of a flash cooling vessel is examined and shown to effect a useful steam saving.

The effect of steam velocity on the mechanical break up of the liquid in a counterflow spray column is shown; an increase in steam flow increased the liquid side disturbance and thus reduced the liquid side resistance giving a greater rate of taint transfer, the characteristic thus more nearly following a line of constant saturation than a line of constant number of transfer units.

A number of flow circuits for deodorizing plant are described. The general conditions limiting the continued reduction in steam flow are discussed.