Ribbon Blenders – Construction and Operation

A ribbon blender consists of a U-shaped horizontal trough containing a double helical ribbon agitator that rotates within. The agitator’s shaft is positioned in the centre of the trough and has welded spokes on which the helical ribbons (also known as spirals) are welded. Since the ribbon agitator consists of a set of inner and outer helical ribbons, it is referred to as a “double" helical ribbon agitator. The gap between the ribbon’s outer edge and the internal wall of the container ranges from 3 to 6 mm depending on the application. Figure 1 shows internal and external ribbon spirals on the agitator shaft located with the blender container.

The ribbon spiral agitator is powered by a drive system comprised of a motor, gearbox, and couplings. Ribbon blenders are generally powered by 10 HP to 15 HP motor for 1000 kg of product mass to be blended. The specific power may range from 3 to 12 kW/m3 depending on the products to be blended.