Laboratory rotary granulators are commonly used for small-batch granulation in pharmaceutical, food, and research applications. They convert uniformly mixed wet powder into granules of consistent size, providing a suitable intermediate product for subsequent drying, sizing, or tableting processes.
Structure and Operating Principle
A laboratory rotary granulator typically consists of a motor, feeding hopper, granulation chamber, rotating blade, screen, discharge outlet, and supporting frame. Its compact design makes it suitable for laboratories and pilot-scale production.
During operation, prepared wet material is fed into the granulation chamber. The rotating blade pushes and compresses the material against a perforated screen, forcing it through the openings to form cylindrical granules. The screen aperture determines the approximate granule diameter, while the operating speed and material properties influence granulation efficiency and granule formation.
Screen Extrusion and Granule Formation
As the blade continuously rotates, the wet mass is evenly pressed through the screen. The extruded material forms short cylindrical granules, which are collected through the discharge outlet. Depending on the material and equipment design, granule length can be influenced by the cutting mechanism and operating conditions.
Different screen sizes can be selected to produce granules of different diameters, making the machine suitable for a variety of formulation development and small-batch production requirements.
Applications and Advantages
Laboratory rotary granulators are suitable for preparing wet granules used in pharmaceutical formulations, traditional herbal products, food powders, and other compatible materials. Their compact structure, removable screens, and accessible contact parts support convenient cleaning and product changeover.
By selecting suitable screen sizes and adjusting operating parameters according to material characteristics, users can improve granule consistency and process efficiency. These machines are a practical choice for research laboratories, product development, and small-scale granulation.
