What is a Vertical Fluidized Bed Dryer?

FANQUN Vertical Fluidized Bed Dryer uses hot air flowing upwards to suspend powders or particles ≤3 mm in a fluidized state to ensure every particle contacts the gas thoroughly, hence can dry rapidly, uniformly, and stably.

How Vertical Fluidized Bed Dryers Work?

The operational process of FANQUN vertical fluidised bed dryers usually comprises the following four steps:

Step 1: Fluidization Formation

When it starts up, the bottom distributor (air distribution plate) creates a consistent and stable high-speed airflow. This passes through the perforated bed plate, gently “lifting” the wet material. Particles separate from one another, become suspended, and enter a state of dynamic motion—known as fluidization.

In this phase, the material no longer accumulates but churns like boiling water; it lays the foundation for initial heat exchange.

Step 2: Full Gas-Solid Contact

When particles are fully “unpacked” and no longer stick to walls, hot air can envelop each particle from 360°.

Fluidized bed drying uses direct gas-solid heat transfer compared to layer drying or surface conduction.

* maximises the contact area between particles and air.

* minimizes the pathways of heat transfer.

* significantly enhances the efficiency of heat exchanges.

Providing fast, uniform drying performance for you.

Step 3:Evaporation of Moisture

In the process of continuous gas-solid contact, moisture on the surface is removed rapidly. While this is happening, the control system maintains a constant final moisture content through parameters such as temperature, airflow, and negative pressure.

Step 4: Material Discharge and Collection

Once drying is complete, the fluid bed system releases the particles through the outlet.

Typically integrated with:

• Cyclone separator: Separates fine dust from main particles
• Baghouse dust collector/filter: catches ultra-fine particles to prevent product loss
• Cooling or screening unit: Prepares material for your downstream processes

Continuously delivering clean, traceable industrial production for you.

Key Components of Vertical Fluidized Bed Dryers

Air Intake Treatment System

The quality of drying depends on the state of the air entering the bed. FANQUN’s air intake treatment system involves multistage control over air purification, dehumidification, and heating to guarantee fluidization stability and consistency of batches.

Inlet air undergoes three-stage processing: primary stainless steel mesh filter (0.15 mm) → F7 medium efficiency filter → high-temperature resistant H13 HEPA filter. This acts to suppress particulate contamination, as well as thermal deformation, risks at the source. The HEPA filter features differential pressure monitoring and quick-release connectors that enable clear maintenance access windows to minimize downtime.

Main System

The main unit consists of a vertically arranged base, material container, diffusion chamber, and filtration chamber to minimize footprint and ensure smooth gravity discharge. The quick-drain valve is located at the lowest point in the cantilevered base with lateral supports for thorough cleaning.

The vertical seal of FANQUN top ring is realized by using two hydraulic cylinders. Silicone bladder seals (0.3 MPa) prevent the leakage of powder, thermal expansion, and pressure imbalance, improving batch consistency. The whole structure meets GMP requirements for your long-term industrial operation.

Material Container

The container supports mobile cart-style loading with braked and swivel casters for precise alignment. Front and rear viewing windows with sealed samplers facilitate observation and quality control. Sintered metal mesh is used in the base of the container instead of conventional screens to prevent secondary distribution, offering wear resistance, heat resistance, extended lifespan, and reduced fine powder leakage.

Containers have quick-release mechanisms and tilt-discharge linkage with lifting actuators, enabling smooth transition between continuous production lines or batch processes.

Diffusion Chamber

The diffusion chamber is suspended from side supports and pivots horizontally for easy maintenance. Multiple vertical spray gun interfaces are flush-mounted internally, ensuring uniform airflow diffusion without blow-off or dead zones. Preset positioning stops and quick-change nozzle seats minimize the time costs of online cleaning, maintenance, and production switching.

Filter Chamber

The filter chamber houses the product filter bags and gas-solid separation system and serves as the core for continuous drying. FANQUN employs a dual-chamber oscillating powder cleaning system: two sets of filter bags clean alternately and maintain stable fluidization without shutdown.

Large-diameter non-metallic pulleys + adaptive tensioning systems reduce wire rope fatigue significantly. In-built bag-to-flange fixation prevents outward flipping, increasing GMP compliance and simplifying manual installation. Vertical relief valves discharge instantly during positive pressure events to prevent bag rupture and secondary contamination.

Atomization System

It has a one-head pressure nozzle with a two-stage atomization structure. Media enters coaxially for uniform droplet distribution. The core peristaltic pump provides stepless speed adjustment and meets the processing requirements for high-viscosity and sensitive suspensions. Atomization gas pressure is manually fine-tuned via a pressure reducing valve, enabling droplet stabilization before hot air introduction to prevent localized clumping.

Muffler System

It is provided with an explosion-proof centrifugal high-pressure blower, isolated from the main unit to avoid the transmission of vibration to the fluidization zone.

Flexible joints, variable frequency drive, and carbon steel mufflers together reduce noise and energy consumption. Exhaust interfaces match your air lines for secondary filtration or VOC treatment.

Control System

PLC control is available with manual/automatic/recipe management modes. Parameter locking and three-tier access permission ensure process consistency. Test and operation states interlock with each other to avoid misoperation. A comprehensive safety system provides interlocks such as pneumatics, sensors, and differential pressure alarms.

FANQUN will retain essential gauges, touchscreens, warning lights, and printer interfaces on your control panel for direct use in pharmaceutical plants or pilot facilities to ensure traceability of data and reusability of parameters.

Key Parameters for Vertical Fluidized Bed Dryers

Among so many models on the market, do you know how to choose a high-quality vertical fluid bed dryer? In order to solve this common problem for most customers, FANQUN designed a parameter chart for you to quickly find a stable and efficient vertical fluidized bed dryer.

Advantages of Vertical Fluidized Bed Dryers

Superior Power

FANQUN combines variable-frequency fans with pneumatic inlet valves, allowing for adjustment of airflow in real time according to feed conditions to prevent under-blowing or over-blowing.

At the same time, synchronized with vacuum feeding, it ensures that materials achieve stable fluidization upon entering the bed layer, initiating efficient drying from the very first second instead of stagnating and building up.

Ultra-Compact Design

The vertically arranged drying chamber uses dual-drive airflow + gravity and helps natural particle descent to avoid sideways buildup.

This translates to:

* Smaller footprint-offering greater economy for plants with restrictions on cleanroom costs, especially pharmaceutical and food plants

* Shorter particle flow paths in the bed

* Smoother discharge process

Uniform Particle Moisture Distribution

FANQUN’s double-stage atomization structure ensures stable heat and mass transfer for moisture-sensitive materials. The envelope-like air film forms around particles, which are kept in full suspension within the drying chamber and always kept in contact with hot air. All the above advantages dramatically reduce the phenomenon of “dry outside while wet inside.”

This process standardizes each particle, achieving near-perfect moisture consistency across batches—crucial for industries like food ingredients, pharmaceutical powders, and functional materials where final moisture content is critical.

Meets sterilization requirements

The overall structure of the FANQUN Vertical Fluidized Bed Dryer meets GMP demands. Valves will automatically shut during shutdown to effectively prevent backflow contamination.

Meanwhile, quick-clean access points are fitted to the filtration section, material container, and diffusion chamber inlet for:

• CIP (Clean-in-Place)

• SIP (Steam-in-Place）

It meets industry demands, whether the application is for medical raw material processing or for food manufacturing.

Suitable for Highly Sensitive Materials

FANQUN equipment provides drying under a nitrogen atmosphere, avoiding particles from directly contacting oxygen in the whole process of drying for formulations prone to oxidation or with solvents inside, such as pharmaceutical intermediates and active yeast.

At the same time, the closed-loop system effectively recovers the volatile organic solvents without their emission into the air. This is not only a question of environmental protection; it is also an important aspect of process safety.

Prevents Blockages

FANQUN incorporates a flared inlet with a quick-acting butterfly valve that allows for fast material transportation under negative pressure to prevent congestion. In case of congestion, an abnormal alarm mechanism that distinguishes pressure difference variations in the internal filter bags starts the vibration cleaning automatically.

Applications of Vertical Fluid Bed Dryers

Vertical fluid bed dryers have extensive applications in many industries, from maintaining flavor in food to ensuring the pharmacological effect of pharmaceuticals. These dryers consistently exhibit excellent drying performance.

FANQUN has been dedicated to the R&D and manufacturing of drying equipment for more than thirty years, and the vertical fluidized bed dryer is one of our most mature products. We have long-term cooperation with domestic universities and materials research teams, realizing the transformation from laboratory technologies into production lines. 

Our services include raw material testing and parameter validation to complete production line design for food, pharmaceuticals, and the chemical industry. 

 If you’re assessing process solutions for free-flowing powders or small granular materials, our engineering team can tailor the equipment directly to your production needs based on your material properties, batch sizes, and industry standards. This ensures more stable drying operations with uniform material distribution.