Bella™ Fluidized Zone Mixer

Super Fast, Gentle, Precision Mixing

The Bella Fluidized Zone Mixer by Dynamic Air features an original design that achieves fast, high capacity, thorough, precision mixing of either dry bulk solids or liquids with solids. Regardless of particle size, shape or density, materials are mixed with a fast, efficient and gentle action. A weightless zone created by low speed counter-rotating shafts generates very low friction without shear. This makes the Bella mixer ideal for fragile products that cannot tolerate rough handling. Even flakes or spray dried bodies remain intact.

Versatile for Liquid Additions

Liquids can be added at much higher rates than normally possible and vast material surfaces are constantly being exposed for maximum dispersion. A wide range of viscosities can be quickly dispersed whether poured, streamed or sprayed. Particle sizes dictate rate and method of liquid addition. In the Bella mixer you can add small amounts of powder or fibers, small amounts of liquid, solid fat (shortening) or liquid fat, or liquid with high viscosity. You can also coat particles or pellets and agglomerate in the mixer.

How it works

The Bella mixer consists of twin drums which have two counter-rotating agitators with specifically angled paddles. The paddles sweep the entire bottom of both mixer drums and yet allow the mixer to be started under full load (figure 1). The material in the mixer moves in a horizontal counter-clockwise direction at the perimeter while simultaneously moving both left and right in the center (figure 2).

The material in Zone B (figure 1) is in its normal gravimetric state as it is being moved and disbursed. In Zone A, a weightless zone is created that effectively lifts the ingredients to an almost weightless state allowing them to move freely and randomly, regardless of particle size and density. Thus, the two zones’ interaction becomes highly efficient as every particle moves rapidly to a highly homogenous mix, the key to the Bella mixing technology for fast, precise mixing.

Options

Liquid Addition with Flow Distortion Bar

When adding liquid to materials which tend to agglomerate, a flow distortion bar is used to improve performance. It consists of a rapidly rotating bar with pins located close together to create a moving curtain of material over the paddles during mixing for maximum exposure to the material (figure 3). This improves product uniformity and liquid dispersion. A fill level of 140 percent of batch capacity is normally required.

Mixing with Pin Mill System

When higher shear is required, the use of the pin mill system is employed (figure 4). It consists of two rapidly rotating bars with pins and a stationary shroud. The pin mill system is used to introduce high shear into the material during mixing for breaking soft lumps and agglomerates that may be present. A fill level of 140 percent of batch capacity is normally required.

Figure 1

Figure 2

Figure 3

Figure 4

See the Bella Mixer in operation

Click the image below to see video clips showing the Bella Mixer at work.