The fluid bed granulator (also known as the fluidized bed granulator) is a highly efficient equipment that combines the functions of mixing, granulating, drying, and coating. It has important applications in the production of instant granules such as coffee agglomerates, milk tea, and traditional Chinese medicine granules. Through fluid - bed technology, powder materials are suspended in the air flow, and an even - sized granule is formed by spraying an adhesive, ultimately resulting in a product with good solubility and strong fluidity. The following is an analysis of its specific applications and advantages in the production of instant granules:
I. Working Principle of the Fluid bed Granulator
1. Fluidization Process: The powder materials are suspended to form a fluidized state by the air flow at the bottom.
2. Spray Granulation: The adhesive (such as water, ethanol, polymer solution, etc.) is atomized through a nozzle and sprayed into the fluid - bed, causing the powder to agglomerate into granules.
3. Drying and Granule Shaping: The hot air simultaneously dries and shapes the granules, forming porous and uniform particles.
II. Core Applications in the Production of Instant Granules
1. Optimization of Granulation Process
1. Structure for Rapid Dissolution: By controlling the spray rate, air - flow temperature, and adhesive dosage, a porous and loose granule structure is formed, increasing the surface area and improving the instant solubility.
2. Component Homogeneity: During the fluidization process, various raw materials (such as sugar powder, medicinal powder, and excipients) are fully mixed, avoiding layering and ensuring product uniformity.
2. Integrated Drying
1. High - efficiency Drying: Granulation and drying are completed simultaneously, reducing the time and energy consumption of multiple steps in traditional processes.
2. Low - temperature Drying: It is suitable for heat - sensitive components (such as probiotics and vitamins), avoiding the destruction of activity by high temperatures.
3. Functional Coating
1. Taste - masking and Moisture - proofing: Coating is directly carried out in the fluid - bed. Film materials are added to mask bitterness or enhance moisture resistance (such as in traditional Chinese medicine granules).
2. Controlled - release Design: Multilayer coating is used to achieve the sustained - release or targeted release of active ingredients.
4. Flexible Control of Granule Characteristics
1. Particle Size Control: By adjusting the spray pressure, adhesive concentration, and fluidization time, granules in the range of 20 - 200 mesh can be produced to meet the needs of different granules.
2. Density Adjustment: By changing the fluidizing air - flow velocity, the bulk density of the granules can be controlled to optimize the dissolution rate of the granules.
III. Advantage Analysis
1. High Production Efficiency: The integration of granulation, drying, and coating shortens the production cycle (it can save 30% - 50% of the time compared with traditional wet - granulation methods).
2. Energy - saving and Environment - friendly: The hot air is recycled, reducing energy consumption; there is no dust spillage, meeting the GMP clean requirements.
3. Stable Product Quality: The automated control system (PLC or SCADA) precisely adjusts parameters, reducing human errors and ensuring high batch - to - batch consistency.
4. Strong Adaptability: It can handle sticky, heat - sensitive, or hygroscopic materials (such as traditional Chinese medicine extracts and probiotic mixtures).
IV. Examples of Typical Process Parameters
Parameter |
Range / Conditions |
Explanation |
Inlet Air Temperature |
50 - 80°C |
Adjusted according to the heat - sensitivity of the material |
Spray Pressure |
0.2 - 0.6 MPa |
Affects the atomization effect and particle size |
Adhesive Concentration |
5% - 20% (such as HPMC solution) |
Excessive concentration may cause the granules to be too sticky |
Fluidizing Air - flow Velocity |
1.0 - 3.0 m³/min |
Key to maintaining the fluidized state |
Drying Time |
20 - 60 minutes |
Related to the moisture content of the material and the particle size |
V. Common Problems and Solutions
1. Granule Caking: Reduce the adhesive spray rate or increase the inlet air temperature.
2. Excessive Fine Powder: Optimize the atomization pressure or increase the adhesive dosage.
3. Insufficient Dissolution Rate: Adjust the granule porosity (such as reducing the drying temperature or extending the fluidization time).
VI. Future Development Directions
1. Intelligent Control: Combine AI algorithms to optimize process parameters in real - time.
2. Development of Green Adhesives: Use natural polymer materials (such as starch derivatives) to replace synthetic polymers.
3. Continuous Production: Break through the traditional batch - mode to increase production capacity.
Summary
The fluid bed granulator, with its characteristics of high efficiency, flexibility, and strong controllability, has become the core equipment in the production of instant granules. By precisely controlling the process parameters, it can significantly improve the solubility, stability, and taste of the product, while reducing production costs. It is especially suitable for high - value - added functional granules (such as traditional Chinese medicine formula granules and protein powder). In the future, with technological upgrades, its application scope will be further expanded.
