Mixing ingredients for baking mixes, instant recipes, drink mixes, nutraceuticals, and cosmetics requires high consistency across batches. Ribbon blenders are a reliable mixer type for this. When determining what size ribbon blender is needed for your recipe, consider the bulk density of the powders. Then, choose a ribbon mixer with the right motor.
Reliability
The versatility of ribbon mixers allows them to be used in various industries, including spices, instant recipes, powdered drink mixes, nutraceuticals, cosmetics, polymers, and plastic compounds. They are also essential for pharmaceutical applications, where they mix powder ingredients with binders to produce tablet formulations and life-saving drugs.
Unlike other mixers, a ribbon blender offers high mixing speeds without causing material damage. However, selecting a correctly sized blender is critical to ensure proper mixing. The component materials’ batch volume and bulk density will determine the correct blender size. Running an overweight batch on a light-duty blender could overload the shaft and spokes, leading to premature mechanical failure.
The ribbon blender features a horizontal “U” vessel with a double-helix, fabricated ribbon agitator that rotates within the container. The ribbon agitator’s movement distributes the mixture throughout the container and eliminates dead spots.
Versatility
Ribbon blenders are capable of handling a wide range of batch sizes. The agitator’s rapid rotation and ribbon flight radial movement enable complete mixing within minutes. The agitator’s shearing force is low enough to preserve the integrity of delicate ingredients.
Ribbon mixers can be equipped with a variety of discharge valve options. Dust-tight knife gate valves are recommended for dry ingredients, and liquid-tight sanitary rotary disc valves are best for wet materials.
The drive arrangement is another key element to consider during ribbon blender selection. A direct-drive system eliminates belt slippage and imposes less overhung load on the motor shaft bearings than traditional belt-driven equipment.
Efficiency
Ribbon mixers offer efficient blending, and their straightforward design simplifies maintenance. Ribbon blenders that employ a direct-drive system eliminate belt slippage and associated downtime issues. Gearmotors work well with variable frequency drives (VFD), providing easy speed control, soft-start capabilities, and overload protection.
The mixing process is influenced by ingredients’ particle size and bulk density; ingredients with similar characteristics mix more quickly than those that differ in these attributes. The ribbon agitator’s shearing force also influences mixing efficiency; ingredients with lower shear rates create fewer dead spots in the batch.
In some applications, liquid ingredients are added through a charge port on the ribbon blender’s cover or a spray bar featuring atomizing nozzles. Testing is recommended to determine a rate of liquid addition that minimizes cycle time without flooding the mixture or forming wet clumps. The spray bar may be connected to a pressure feed vessel in sanitary applications. Optional PLC recipe controls enhance batch-to-batch consistency and allow for automated data logging.
Safety
Ribbon blenders work well with a wide variety of powders and bulk solids. They can be used to mix spices, instant drink mixes, nutraceutical products, cosmetic powders, and even pharma ingredients for tablets and life-saving drugs.
To prevent any potential issues like clogging, ribbon slippage, or contamination, the agitator shaft must be properly matched to the physical properties of the product being processed. Simple customizations like match marks on the agitator shaft flanges can help ensure a quality blend in less time and more efficiently.
Moreover, modern gear motors can provide greater operating efficiency and performance over belt or chain-driven systems more prone to mechanical failure. A variable frequency drive (VFD) on your ribbon mixer can offer additional benefits such as electronic speed control and soft-start capabilities.
