ANDRITZ Fluid bed spray granulation SGS: From liquid to bulk in one step
The spray granulation process converts a water-containing solution, paste or suspension or a melt into a granule. The granulation and the drying processes take place at the same time. Any kind of crystallization and mechanical dewatering equipment can be replaced by an SGS type fluid bed. The final product granules are dust-free and easy to handle.

Typical design of SGS for Urea
The purpose of the spray granulation process is to generate a particle with a defined structure, size, shape, and composition. In comparison to mechanical granulation processes, the spray granulation process has some major advantages related to the quality of the final product, such as:
- Almost spherical shape
- Dust-free
- High bulk density
- Perfect flow characteristics without attrition
- Narrow particle size distribution
- Good transport, storage, dosing, screening, and packing properties
The granulation and the drying processes take place at the same time. Any kind of crystallization and mechanical dewatering equipment can be replaced by an SGS type fluid bed.
The primary product is sprayed directly through a number of specially designed nozzles into the fluidized layer. The liquid droplets that form during spraying impinge on an existing granule particle in the fluidized layer. The water content of the droplet evaporates from the surface of the particle and the solid content remains due to the binding properties of the individual product. Thus, the particles grow layer by layer until the final granule size is reached and the particle leaves the fluid bed.
Your benefits
- High-quality products with spherical granules
- Less equipment than conventional processing
- Enhanced control over product properties like bulk density, PSD, etc.
- Excellent handling features due to free-flowing, dust-free product
- High single-line capacities

Typical system set-up with an SGS fluid bed dryer