A common form of homogenisation technology is the rotor/stator system according to Professor P. Willems. Various types of rotors and stators determine the dispersing result – depending on the rotational speed.
How a rotor/stator system works
- 1SuctionThe product is drawn centrally into the rotor/stator system.
- 2AccelerationThe fast-running rotor accelerates it centrifugally outwards.
- 3ShearingAt the toothed rings it is strongly accelerated and braked almost to zero at the shear gap.
- 4Size reductionThe high-frequency shear forces ensure an optimal dispersing and emulsifying effect.
A stable emulsion requires the largest possible total droplet surface – this is only achieved with very small droplets and a suitable emulsifier, e.g. for oil/water or water/oil emulsions.
Applications of homogenisation technology
Emulsification
Mixing two liquids that do not mix stably: a hydrophobic phase (e.g. oil) and a hydrophilic phase (e.g. water) are permanently combined.
Suspension
Distributing an insoluble solid in a liquid – often with high turbulence and special rotor geometries, e.g. for active substances or colour particles.
Dissolving
Dissolving substances in a liquid usually requires high turbulence to ensure efficient production times.
Disagglomeration
Incorporating and breaking down dry particles (e.g. powders) in liquids. Dry powders tend to form lumps.
Decisive for fineness: geometry, shear gap and tip speed
Whether emulsion, suspension, solution or disagglomeration – three factors determine how fine the result of a homogeniser will be:
The design of the rotor/stator system is decisive for an optimal dispersing effect. With many years of experience, SEEFRIED Verfahrenstechnik GmbH designs the right dispersing system for your task.
Frequently Asked Questions about homogenization technology
How does a rotor/stator homogenizer work?
The rotor runs past the toothed stator at high speed. The product is drawn in centrally, accelerated outwards and sharply decelerated in the shear gap between the teeth. The resulting shear forces break up droplets and particles and ensure an optimal dispersing and emulsifying effect.
What determines the fineness of an emulsion or suspension?
The decisive factors are the geometry of the rotor/stator system (number of teeth and tooth rows, size of the tooth gaps), the shear gap width and the peripheral speed – each matched to the viscosity and sensitivity of the product.
What is the difference between emulsifying and suspending?
Emulsifying permanently mixes two immiscible liquids, such as oil and water, usually with the help of an emulsifier. Suspending distributes an insoluble solid evenly in a liquid.
Can you help select the right homogenizer?
Yes. Based on many years of experience, we design the appropriate rotor/stator system for your product and process requirements.