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Wurster Coater/Wurster Fluid Bed Spray/Coating Machine/Granulator

Functionality:

  • Top Spray Type: This versatile system excels at drying wet granules or powders, granulating, and drying by spraying binders onto fine powders.
  • Bottom Spray Type: Ideal for suspending sprays on pellets or films, including enteric coating applications.
  • Side Spray Type: Perfect for pellet powder coating, suspension coating, or film/enteric coating needs.

Theory:

Top Spray Type: In the top spray configuration, heated and purified air is drawn into the column by a suction fan, creating a uniform fluid condition within. To prevent powder leakage, a single filter bag is employed. As the air circulates, it evaporates moisture, effectively drying the contents. By introducing an additional spray gun, binders or active ingredients can be directed downward into the uniform fluid powder. This process results in granulation, and the granules are subsequently dried to achieve the desired moisture content.

Bottom Spray Type: In the bottom spray setup, when hot air flows through the bottom screen of the coating column, it generates a siphonal effect. Strong forces create convection, causing granules to be drawn into the coating column and move from the bottom to the top. These granules then fall back down, and a bottom spray gun sprays upward onto the uniform fluid granules, achieving both coating and drying.

Side Spray Type: For the side spray method, sugar cores are positioned on a turntable. Hot air is blown upward between the turntable and the granulation area, causing the cores to rotate. A binder solution is sprayed onto the rotating cores via a pump and spray gun, achieving simultaneous coating and drying. In cases where powder coating is required, a fixed volume of powder is simultaneously sprayed, allowing the solution to coat the powder on the cores. This process results in the production of pellets while achieving the desired coating and drying effects.

Wurster Fluid Bed Spray Coating Machine
Wurster Coater

Applications of Wurster Fluid Bed Coating Machine:

Top Spray Type:

  • Pharmaceutical: Suitable for granulating and drying Chinese or Western medicines, as well as biotech products.
  • Instant Food: Ideal for granulating and drying instant powder formulations of health foods, juice extracts, meat extracts, seasonings, and lactic acid bacteria.
  • Chemical: Effective for drying dyes and synthesis raw materials.

Bottom & Side Spray Type:

  • Used to produce pellets for pharmaceuticals and health food products.