Solid-Liquid Mixing

The classic agitation method is not always sufficient to mix solid and liquid substances, as Agitation often results in the formation of Agglomerates, air intake, high dust generation or solvent emissions. This Agitation function is often referred to as Suspension, whereby the solid substances can be soluble as well as insoluble. If solid and liquid substances are mixed with an agitator, it can result in the solid substance adhering to the agitator, quality variation and the loss of raw materials. Solid-liquid mixing prevents all these undesirable side effects by wetting the solid substances and then combining Mixing, Homogenisation and Dispersion combined in one passage. This procedure thus saves time, as well as personnel, cleaning and energy costs.

A rational weighing and dosing within the process is achieved by means of our new Dosing Station.

The solid-liquid mixing process takes place in homogenisation mixers, on which we can offer you expert advice.

From a physical point of view, solid-liquid mixing is a three–phase system consisting of a solid, the surrounding atmospheric gas phase and a liquid. If a liquid is in contact with a moving solid mixture, the quantity of liquid and its dispersibility determine the extent to which the individual particles are wetted. The dispersibility of a liquid is mainly dependent on the following physical properties: Surface tension and viscosity of the liquid, porosity of the solid, affinity of the solid and liquid phase (lipophilic – hydrophilic), as well as the efficiency of the material distribution.

Applications

Suspension of solids in liquids, such as powders, granulates or bulk materials, is a complex process that is used in many industries. In the pharmaceutical industry, for example, the coating materials (coating) of tablets is produced by the incorporation of solids into aqueous solutions. The preparation of Suspensions of colour pigments is one of the typical applications in the production of dyes.

Other common applications are the production of:

• Colour pigments
• Suspensions
• Toothpaste

Details

When mixing solid and liquid substances, it is important that the entire quantity of the solid substance is incorporated into the liquid. No residual quantities should remain in the supply containers and feed pipes. Likewise, the solid substance should not swirl up and adhere to the inside of the container lid. The suspended solid should then be homogenously distributed, not combine to form Agglomeration and not form sediment on the bottom of the vessel.  
Suitable mixing vessels solve this by means of powder sucking with a pre-mixing phase without re-wetting of the solids and agitators, which apply a sufficient flow velocity to each part of the mixing vessel to achieve the above-mentioned objectives. Depending on the raw material and the process, however, a detailed technical design in advance is also necessary here to achieve subsequent optimal production conditions. We will be pleased to advise you on the subject of solid-liquid mixing.

Liquid raw material components are optimally dosed by means of our Dosing Station.