As the name hints, a static mixer has no moving parts. It relies on gravity and a combination of straightforward mathematical concepts to perform its blending tasks. What tasks can they perform efficiently, and where do they differ from the tasks a self-pumping mixer performs?
A triple action static mixer is very powerful, combining multiple mixing concepts. Something as simple as two-by-two division can result in more than a million divisions over just twenty elements.
That’s powerful, and it’s also simple. There’s less maintenance on static parts, and there are far fewer things that can break down and go wrong. This makes static mixers much simpler to manage than self-pumping mixers.
They’re very effective for blending multiple liquids, dispersing gases into liquids, and continuous operations. They’re also often easier for scale-up in the amount of materials you’re mixing and outputting.
Self-pumping mixers have advantages, too. They can create a high shear that homogenizes certain materials. Creating fine suspensions and incorporating powders are handled well by these, as are combining materials that react on contact. The maintenance cost of self-pumping is higher and they can break down more often (they simply have moving parts where static mixers don’t), but a self-pumping mixer may save you the cost of an auxiliary feed pump.
For many of these operations, the two are best used together. It really depends on the operation you’re conducting. Static mixers have a place almost anywhere where you need industrial mixing. By combining many simple concepts into a complex series of mixing elements that each build on the last, static mixers can accomplish the vast majority of industrial mixing tasks. Whether you add a self-pumping mixer to the picture depends on very particular needs such as emulsion or disintegration requirements.
Triple Action Mixing Efficiency
A triple action static mixer is one of the most powerful static mixers available. Aside from the two-by-two division described above, it also utilizes cross-current mixing through special cavities that randomize the distribution of material through direct stream impingement. Randomization builds directly on the two-by-two division to make it even more effective.
The third action uses counter-rotating vortices and back-mixing. As flow increases, elliptical vortices are created. They rotate in opposition, eliminating any streaming effect. This also increases back-mixing as material is orbited through the vortex.