Page 367 - APPLIED PROCESS DESIGN FOR CHEMICAL AND PETROCHEMICAL PLANTS, Volume 1, 3rd Edition

Mixing of Liquids 335

PRINCIPLES OF OPERATION RADIAL MIXING
The Kenics STATIC MIXER unit is a series of fixed, helical
elements enclosed within a tubular housing. The fixed geo-
metric design of the unit produces the following unique
patterns of flow division and radial mixing simultaneously.
FLOW DIVISION

In laminar flow, a processed material divides at the leading
edge of each element and follows the channels created by In either laminar or turbulent flow, rotational circulation
the element shape. At each succeeding element the two of a processed material around its own hydraulic center in
channels are further divided, resulting in an exponential each channel of the mixer causes radial mixing of the
increase in stratification. The number of striations pro- material. All processed material is continuously and com-
duced is 2n where n is the number of elements. pletely intermixed, resulting in virtual elimination of radial
gradients in temperature, velocity and material compo-
sition.
Element Number
2 3 4 5 Clockwise Rotation Counter Clockwise Rotation
Right-Hand Element Interface Left-Hand Element
ES, .. .

2 4 8 16 32 '
Number of Striations

Figure 5-43. Principles of operation of static mixer modules. By pennission, Kenics Corp., Div. Chemineer, Inc.

Figure 5-44A. Two
details of the Dow
motionless mixer. By
permission, Charles
Ross and Son Co.

Figure 5-448. The
Dow interfacial sur-
face generator is
mathematically pre-
dictable. By permis-
sion, Charles Ross
and Son Co.