Fluidized spray dryer

Fluidized spray dryer is not only a drying equipment, but also an efficient "particle designer". Its main function is to convert liquid raw materials into spherical agglomerated particles with ideal particle size, excellent solubility, and high fluidity in a single device in one step, while achieving higher energy efficiency and production efficiency.

To understand it as:

Spray drying tower+fluidized bed dryer=fluidized spray dryer

The utility model is structurally characterized in that a fluidized bed is installed at the conical bottom of an ordinary spray drying tower.

Main purpose and working principle

Its main use goes beyond simple drying and focuses more on building the required particle characteristics such as particle size, density, flowability, and solubility. The workflow is as follows:

Stage I: spray drying (primary drying and granulation)

The liquid material is atomized into fine droplets by the atomizer at the top of the tower (centrifugal, pressure or gas flow).

These droplets come into contact with the high-temperature air introduced from the top of the tower, causing rapid evaporation of moisture and initial drying of the surface, forming tiny solid particles or viscous particles in a "semi dry" state.

These particles fall to the bottom of the tower under the action of gravity.

Phase 2: Fluidized bed drying and granulation (secondary drying and shaping)

At the bottom of the tower, there is a fluidized bed composed of porous plates. Another hot air blows upwards from the bottom through the orifice plate, causing the falling particles to be blown up, suspended, and in a vigorous "fluidized" state of motion, like boiling liquid.

The key role occurs here:

Continue drying: The particles are further and more gently dried in the fluidized bed to ensure that the moisture content reaches an extremely low standard.

Agglomeration granulation: Semi dry particles with a slightly viscous surface collide and adhere to each other in a fluidized bed, forming larger, porous agglomerated particles.

Particle shaping: Intense exercise causes the edges and corners of particles to be "rounded", forming more regular and flowable spherical particles.

Cooling: At the end of the process, cold air can be introduced to cool the product for subsequent packaging.

Outstanding advantages of fluidized spray dryer

Thermal efficiency: the traditional spray drying tower is usually high, with short residence time of hot air, high exhaust temperature and large heat loss. The fluidized bed section underwent secondary drying at the bottom of the tower, significantly reducing the exhaust temperature and improving the thermal energy utilization efficiency.

Excellent product performance:

Control particle size: It can produce agglomerated particles with larger particle size and uniform distribution.

Improving solubility: The formed porous agglomerated particles have instant solubility and will not clump during blending.

Improve flowability: Spherical particles have good flowability, which facilitates subsequent packaging, transportation, and measurement.

Reduce dust: Due to the formation of larger particles, the fine powder content in the product is greatly reduced, improving the production environment.

Integrated process: Integrating multiple unit operations such as drying, granulation, and cooling into one device simplifies the process and saves equipment and space investment.

Flexible adjustment: By adjusting the atomization parameters and fluidized bed parameters separately, the particle size, density, and moisture content of the final product can be flexibly adjusted within a certain range.

Main application areas

This type of equipment is particularly suitable for producing products with high requirements for adjustability, fluidity, and particle morphology.

Food industry:

Milk powder (especially instant infant formula, soy milk powder).

Solid beverages such as coffee, tea, cocoa, etc.

Wheat extract and starch sugar.

Seasoning and food additives.

Pharmaceutical industry:

Granules and granules.

Enzyme preparations, dry yeast.

Precursor of pills - granulation.

Chemical industry:

Detergents and catalysts.

Polymer and ceramic powder.

Schematic Diagram of Fluidized spray Dryer