Processing Magazine

The secret behind the Bella Fluidized Zone Mixer

January 23, 2008
The Bella fluidized zone twin shaft paddle mixer by Dynamic Air achieves fast, high-capacity, low shear, 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 with typical mixing times of 15 to 30 seconds. A weightless zone created by low-speed counter rotating paddles generates very low friction without shear. This makes it ideal for abrasive products and fragile products that cannot tolerate rough handling. Even flakes or spray-dried bodies remain intact. The Bella mixer consists of twin drums, which have two counter-rotating agitators with specifically angled paddles. They overlap at the center and completely sweep the entire bottom of both mixer drums and allow it to be started under full load. 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. The material in Zone B is in its normal gravimetric state as it is being moved and disbursed. In Zone A, a weightless zone is created which 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 homogeneous mix, the key to the Bella Mixer mixing technology for fast, precise mixing. The Bella mixer is available in stainless steel for food applications. Custom sizes, finishes and materials of construction are available upon request.