EEMS - Energy Efficient Milky Sprays

EEMS – Energy Efficient Milky Sprays

Spray drying is a very energy intensive process to dry milky products into a functional powders. EEMS is about reducing energy requirements in spray drying processes.

In short:

  • Spray drying is used to dry milky products into functional powders
  • Drying is a very energy intensive process using hot air
  • Higher solids loading has the potential to save 20% energy


Spray drying is a very energy intensive process to dry amongst others milk products into a functional powders. A liquid with typically 50% solids content (absolute level highly depending on composition) is atomized in a high pressure atomizer and dried under the influence of hot air. The internal liquid flow in a high pressure swirl nozzle largely influences the liquid sheet breakup and hence determines droplet size distribution, which in turn determines spray drying efficiency and product quality. High solid content liquids are typically highly viscous and depending on composition can exhibit non-Newtonian flow behavior.

Currently the level of understanding is not yet sufficient to allow for a higher solids loading, which has the potential to lead to a 20% energy reduction, because more of the liquid can be evaporated in the more efficient evaporator or by reconstituting at a higher solids content. The EEMS project aims to develop fundamental understanding on the complex fluid dynamics inside the nozzle as well as the liquid sheet breakup, through high fidelity numerical simulations and non-invasive monitoring techniques.


EEMS aims to study the effect of solids content and main constituent components of model liquids on atomization efficiency of the nozzle. Ultimately this will lead to recommendations for design and operational principles to help meet the Dutch climate agreements to reduce greenhouse emissions by reducing the energy requirements of spray drying processes.

Acknowledgement & partners

This project is co-funded by TKI-E&I with the supplementary grant 'TKI- Toeslag' for Topconsortia for Knowledge and Innovation (TKI’s) of the Ministry of Economic Affairs and Climate Policy.