A spray dry process performs the action of separating water or another liquid from a solution, an emulsion or a suspension, for the purpose of obtaining the solid part of the feed fluid under the form of powder.
This is obtained pumping the liquid feed product into a tower, where the same is atomized into drops and put in contact with a stream of hot air. By heating trough thermal convection, the liquid part of each drop evaporates, leaving the solid residue of the drop falling to the bottom of the tower as a powder grain.
CENTRIFUGAL PRESSURE NOZZLES
The most widespread pressure atomizer , where the energy for atomization is supplied exclusively by the feed liquid pressure. In this type nozzle the liquid enters the whirl chamber through a slot in the side of the chamber itself, follows a tangential path around the inner chamber profile, and is then fed to the outlet orifice at high speed. Nozzle orifice, whirl chamber and nozzle top plate are made out of tungsten carbide or other wear resistant materials, to avoid rapid wear and consequent performance degradation. Bodies are manufactured from high quality Aisi 316 stainless steel. These nozzles are well suited for atomizing high viscosity liquids with viscosities values up to several hundred centipoises. They are successfully used in countercurrent spraydryers, and in systems using multiple nozzle lances. Capacities range up to several thousands of kgph for a single nozzle.