Abstract

The spray drying process is involved in numerous industrial applications. A field of special interest, in which this process is used, is the production of nanostructured granules obtained from nanometrical-sized raw materials. In this work a study of the drying process of nanofluid droplets has been carried out in an acoustic levitator. The study was extended to the drying of droplets of suspensions containing mixtures of nanoparticles and microparticles. The influence of the variables of interest in the drying kinetics, the packing of the particles inside the granule, its internal microstructure and its mechanical resistance has been analyzed and modeled. Finally, the results obtained from the drying of individual droplets in the acoustic levitator have been validated at pilot plant scale by spray drying of different suspensions.