The fluidized bed spray granulation is an innovative method to gain compact and nearly round granules with extraordinary physical properties. The solid-containing liquids (e.g. suspensions or emulsions) are atomized in the fluidised bed and, as little droplets, hit the granule seeds. Thus, the liquid evaporates and the solid substance is drawn on the granule seed, forming a stable coat. This is continuously repeated in the fluidised bed, so that very compact, shell-like granules are produced. This is called layering process.
In fluidised bed spray granulation, parameters like particle size, residual moisture and solid content can be precisely adjusted, so that the most different substances can be processed to granules. As, during granulation in fluidised bed, the processes of drying and shaping are being operated simultaneously, this process is also called fluidised bed spray drying granulation.
The continuous fluidised bed spray granulation is suitable for all applications requesting a homogeneous, dust-free granule with high bulk density. It is an interesting alternative to classical spray drying which often does not allow to clearly define and set the quality of the final product and which must be followed by additional processes. Spray granulation produces a very homogeneous granulate with a defined particle size distribution and exact residual moisture, which is dust-free and has excellent flow properties.
Example of application: Shaping of liquids
A liquid complexing agent with 40 % dry matter is converted into free-flowing, compact granules.
Spray drying with simultaneous agglomeration by agitation, melt crystallization, layering processes
Examples of products:
- Flavours, flavouring sources
- Protein concentrates and hydrolysates
- Instant coffee (coffee extract)
- Liquid egg
- Inorganic and organic salt solutions
- Plant extracts
- Organic acids
- Colouring agents, pesticides and fertilizers
- Minerals and ceramics
- X-ray contrast agents
- Calcium lactate
- Aluminium oxide