Spray drying

spray-drying
© Fraunhofer IGB
Schematic diagram of the spray-drying process.

Producing solid powders from solutions and emulsions

The spray process is a special method of converting a solution, suspension or emulsion into solid powder form in a single process step. Spray drying is a recognized process in many branches of industry such as pharmaceuticals, food sciences, chemistry or materials science.

In addition, many other processes can be completed in a single step:

  • Modifications of the particle size
  • Agglomeration of nanoparticles
  • Drying of suspensions
  • Further particle coating for protection against e.g. acids
  • Immobilization of liquids and solid materials in a matrix
  • Production of microcapsules

Mini spray dryer for rapid drying of heat-sensitive substances on a laboratory scale

With the nano spray dryer in our laboratory (spray dryer B-290 from Büchi) particles in the range of 300 nm up to 5 μm can be produced. The electrostatic particle separator ensures yields of up to 90 percent for sample quantities in the milligram range. Conventional methods achieve yields of only 60-70 percent. This enables experimental work with the smallest substance quantities for feasibility studies - ideal for R&D feasibility studies of high-quality pharmaceutical formulations and formulations of nanomaterials.

In addition, the mini spray dryer is the perfect solution for fast, consistent and gentle drying of heat-sensitive molecules in aqueous and organic solutions into free-flowing powder and is ideal for high-quality cyclone separations with high yield and minimal product losses and easy scale-up of processes to an industrial production scale.

Application areas and references

 

Spray drying: Perfect dosing thanks to drug capsules

Instant coffee and powdered milk are produced by spray drying. Fraunhofer researchers have adapted this technique to the tricky question of incorporating insoluble substances in core-shell particles. The new method helps reduce the concentration of active ingredients in therapeutic medications.