The suspension process involves mixing two bodies of different sizes (liquid/solid) in order to, thanks to the force of movement and the energy generated, raise all the bodies in the vessel. The fluid will thus drag the isolated solid particle in a movement somewhat different from its own.

Suspension is a process that allows the dispersion of a solid in a liquid when a liquid/solid mixture is mixed. This operation is carried out by stirring so that the movement generated and its energetic power carries the solid particles (solid phase) into the continuous liquid phase. Suspension is therefore a system that remains heterogeneous. It is suitable for mixing all types of solids or powders, whatever their size, shape or density.


In industry, this process is generally implemented by the technique that combines tank and agitator. Suspension is considered complete when no solid particles remain stable at the bottom of the tank or on the surface of the moving liquid.
Thus, not only must the solid parts be detached from the bottom of the tank and not appear on the surface, but also the power generated for the suspension must be sufficient to prevent the redeposition of the solid particles or their rising to the surface of the liquid.


Suspension is a step associated with the process of maintenance in suspension, which ensures and maintains the homogenisation of a solid/liquid mixture.

Frequently used in the chemical, pharmaceutical, cosmetic or food processing industries, suspension operations are carried out in tanks (or other reservoirs) by means of stirrers equipped with mobile devices such as turbines or propellers, and sometimes with anchors.


Compared to a solution, suspension makes it possible to improve the chemical stability of certain active ingredients, as is the case in the pharmaceutical industry for the preparation of certain antibiotics.


The quality of the mixture to carry out this operation depends on many parameters: stirring speed, dynamic viscosity of the liquid phase, mass and volume fraction of the solid particles, or even the diameter of the tank and the angle of inclination of the blades of the mobile ensuring the movement.
The correct consideration of these data is an essential prerequisite for determining and opting for the most suitable system, as well as a major challenge for the optimization of any industrial application requiring a suspension process.


In the suspension process, propellers and turbines are the most commonly used stirring mobiles, especially models offering a high shear rate for mixtures involving solids that are denser than liquids.

Equipment adapted for the application: Suspension :


stirrer propeller high speed shear dissolution
Ax2 propeller for stirrer, pumping and shearing
stirrer propeller high hydraulic lift
Ax1 propeller for stirrer, hydraulic lift, optimized shear
stirrer propeller mixtures of shear-sensitive products
Marine propeller for agitator, for shear sensitive products
stirrer propeller liquid mixture containing fibers
Ax4 propeller for stirrer, liquid mixtures with fibers


stirrer curved blade turbine
Hydraulic Turbine Stirrers 3PC 6PC maintenance in Suspension
stirrer turbine starting mixtures in decantate
Stirrers Turbine with 2, 3 or 4 blades at 45°, Axial/radial flow
stirrer flat turbine with straight blades
Turbine TF2, TF3 flat with straight blades for stirrers