STATIC-MOTIONLESS MIXERS HOW THEY WORK

Showing 2 Component static motionless mixing schematic

Static Mixers (or motionless mixers) are designed to mix materials with equal or different viscosities and different flow rates.  Used as in-line mixers they have been used successfully for many years in the reaction and heating of cooling of liquids, mixing and dispersing, slurries, multi-phase contacting of gases and solids and liquids.

 

The selection of the correct mixer for your application is based on the process unit operation being practiced.

(Figure A) In continuous processes, static mixers create a homogeneous

mix in a short length with no moving parts.

Static or Motionless mixers are used in either a continuous process where they homogenise fluids or usually in their plastic form are used as a disposable mixing solution such as applying curing agents and two pack resins. (see figure a).  Pumps or blowers are used to transport the mixing components which also control the flow rates and pressure required form mixing.

 

A static mixer consists of individual mixing elements stacked in series (figure B). Each mixing element is oriented 90 degrees relative to the adjacent mixing element to create homogeneous mixing in both the horizontal and vertical directions. The static mixing elements divide and recombine the feed materials so that the stream exiting the static mixer is homogeneous with regard to concentration, temperature and velocity which are equalized throughout the entire pipe cross-section.

Choosing the Correct Mixer

GX Mixers - Figure B

The correct static or motionless mixer will depend on your process and the system requirements, the fluid properties, the level of mixing required and and pressure drop limitations must be taken into account.

 

The GX X Grid design (figure b) has a dramatically better mixing properties when compared to a simple HT Helix mixer.

 

This design is more expensive but to get to the true costs it is important to consider, better control of the mixing head, less wasted mixing components for disposable applications and shorter mixing housings required for fixed installations.

 

Using a Helix HT mixers is still very popular due to it inexpensive design, low pressure drop and its open none fouling design. (figure c)

 

However compared to a GX X grid design (figure b) its mixing performance is much lower than an X grid design so much long mixing channels will be required to achieve the same level of mixing.

 

Brochures & Technical Downloads

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Table showing mixing properties of a GX static mixer

Helix Mixers - Figure C

Table showing mixing properties of a helical static mixer

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