It's bubbling like a volcano: in our fluidized bed plants, particles and gases collide in a fascinatingly dynamic process. This highly efficient technology allows the properties of powdery and liquid substances to be specifically modified – for products with improved application behavior and genuine added value. But which operating mode is the right one? We explain when continuous operation is worthwhile and when a batch process is advantageous.
What happens inside a fluidized bed reactor is both spectacular and technically sophisticated. When air or a gas, such as nitrogen, flows through a powder or granulate at a sufficiently high speed, the product layer lifts and enters a fluidized state. The particles are then in intense motion, behave similarly to a liquid, and are surrounded by air. This makes the entire surface accessible to process air and to liquids, emulsions, or suspensions that are sprayed on. These conditions are ideal for highly effective drying processes, as well as for processes such as spray granulation, agglomeration, and coating.
Depending on the product, process requirements, or production strategy, the fluidized bed process can be operated either continuously or in batches. Both operating modes have specific advantages.
Continuous fluidized bed
For large production volumes and consistently high product quality, continuous processing is typically the most economical solution. Our plants guide products continuously through various zones, where process parameters can be precisely adjusted. This ensures agglomeration, granulation, and drying occur simultaneously and are optimally coordinated. The entire process – from raw material input to finished granulate – is fully automated.
Survey of the benefits
Throughput ranging from a few kilograms to several tons per hour
High process stability and minimal manual effort
Scalability for growing production volumes
Optimized routines keep product losses below one percent
Long production times without cleaning interruptions
An integrated WIP (Washing-in-Place) system makes cleaning easy
Flexible adaptation to customer-specific requirements
How it works: The raw material is dosed at the front via a loss-in-weight feeder with a downstream double flap system. Then, fluidizing air is blown in through the air distribution plate to enable optimum heat and material transfer. The product is continuously discharged at the end of the apparatus and supplied to downstream process steps. Depending on the design, the exhaust air leaves the system via a hood with integrated filters so that the product dust remains in the process. If necessary, the exhaust air is cleaned using a cyclone separator and a downstream total separator.
Typical areas of application include: Food industry, fine chemicals, biotechnology, and increasingly, the pharmaceutical industry.
Fluidized bed batch process
On the other hand, the batch process offers advantages when frequent product changes, smaller campaigns, or complex recipes are required, and when throughput times are not a key factor. All process steps are carried out sequentially in a closed bin. This makes it easy to adapt to different formulations and enables precise control of each individual batch.
Survey of the benefits
Ideal for research, development, and small production runs
Easy to scale up
Easy setup and intuitive operation
Flexible adjustment of process parameters to changing requirements
Uncomplicated product changeovers and simple GMP validation
Modular design – from a few grams to batch sizes of 2,000 liters
How it works: Our batch plants can process powders, granulates, and pellets, as well as liquids. For example, they can be used for spray granulation or microencapsulation. Typical applications include drying, agglomeration, coating, and combination of process steps. The plant is easy to clean between batches, which is an advantage when changing products. The product and technology areas are clearly separated from one another to ensure that hygiene requirements are met. The basic configuration consists of the fluidized bed apparatus, the Batch FB, the supply and exhaust air systems, and the control system. Additional options can be retrofitted at any time.
Typical areas of application include: Pharmaceutical industry (due to clear validation and GMP requirements), as well as research and development.
Which solution best meets your needs?
Both operating modes - batch and continuous - enable the economical production of homogeneous products with specifically improved properties. The right option depends on your specific requirements, throughput volumes, and general conditions. Since there are hardly any standard solutions in fluidized bed technology, we design each plant individually. This process draws on our expertise in process engineering, our understanding of raw materials and substances, regulatory requirements, industry-specific processes, and current market trends. This ensures that the technology and application are perfectly matched for efficient, safe, and economical processes.
Exemplary product samples from various fluidized bed processes
1 Seed (coating), 2 Cocoa (agglomeration/instantization), 3 Extruded instant tea (drying), 4 Stevia (spray granulation), 5 Plant protection products (microencapsulation), 6 6 3-in-1 cappuccino (agglomeration), 7 Sugar + fat + color (coating), 8 Malt (spray granulation), 9 Instant coffee (spray granulation), 10 Curry sauce powder (agglomeration/instantization), 11 Vitamin drink (agglomeration/instantization), 12 Milk powder (agglomeration/instantization)
