Wet Milling Machines

Wet Milling Machines

Wet Milling Process

A wet milling process refers to mechanical shear and grinding that reduces the primary solid particles of a slurry to smaller sizes. A slurry is simply a mixture of solids, or aggregates, within a liquid medium. Some mechanical shearing device is used to grind up particles or agglomerates between solid mechanical components moving or rotating at high speed. Bead mills use spherical balls or beads that tumble inside a rotating housing as a slurry passes through. Colloid mills are typically used as well and tend to be more efficient than bead mills.

Wet milling process equipment is very mechanical in nature and tends to operate at low flow rates and has more wear than say propeller agitation, but propeller mixers provide lengthy mix times to achieve decent particle sizes.

Wet Milling Machine

rotomill diagram

Milling Machines

Wet milling machines are used in the process of wet milling various slurries comprised of solids and liquids in a rough mixture. When combining liquids and solids, the key to manufacturing success is how well the solids can be wet out and dispersed into proper suspension in the liquid portion of the solution. A variety of wet milling machines can be used including ball mills, bead mills and colloid mills, all of which essentially grind the solids within the liquid phase through mechanical rotation or milling. A premix slurry is made in a vessel with agitation and typically, this level of agitation is not sufficient to disperse the solids effectively within the liquid medium. 

Our RotoMill Colloid Mills use a rotor element that turns at high speed inside a mating stationary component. The grinding action in the gap between the elements creates mechanical shear and milling while pumping the slurry out. The reduction in the primary particle size of the solid phase allows for a superior suspension with the added benefit of improved product appearance and performance.

Reduces Particle Sizes

Zinc and titanium dioxides, talc, salts, talcum, calcium carbonate and other solids need to be effectively ground down to manageable sizes to create better dispersions. A dispersion is similar to that of a wet slurry that involves processing the solids into a finer suspension.

When wet milling equipment is used to make these dispersions, it’s important to isolate the mechanical seal from the process slurry.  Sonic offers a Seal Flushing system that provides improved performance and simplicity above the age-old pressure pot units that resemble something off a world war sub.  Instead of using a completely pressurized vessel with a hundred bolts holding it together, we offer a simple vessel that is not pressurized and a PD pump that pressurizes the seal chamber by pumping through an adjustable valve that generates pressure.  This way, only the seal chamber sees the pressure instead of the entire piped system and vessel.  The vessel is jacketed to provide cooling and contains instrumentation such as level sensor and temperature sensor to monitor flushing fluid.  These are clean, sanitary assemblies using stainless tubing and sanitary connections.

Download a FREE
Wet Milling Machine
Colloid Mill e-Booklet!

Colloid Mill Booklet

Go to Top