The Nara-designed Media Slurry Dryer makes it possible to dry from slurry to fine powder in one step – i.e. without additional desagglomeration. This is due to the following process: The slurry is fed by a pump into the media beads which are in fluidised state by means of the incoming hot air. The slurry is dispersed and forms a film on the media surface. Because of the very large surface area of the media, the volatile slurry component dries in a short time. The left-over dried solids are peeled from the media surface because of the continuous collisions the media particles undergo. The peeled-off solids are transported to the dust separator by entrainment into the exhaust air.
Special features of the NMSD:
• its compactness
• the good thermal efficiency
• easy maintenance
• the nearly same size of the powder particles and the solid particles in the slurry
Materials this drying method is most suited for are: inorganic materials like calcium carbonate, calcium phosphate, glass powder, magnesium hydroxide, silica and zinc sulphide. But also materials like animal blood, emulsion resins, dyes, pigments and medicines can be dried very effectively in this way.
The capacity of the dryer depends on the fluid bed area, the temperature and the material. The evaporated water quantity of actual plants ranges from 2 kg/h (laboratory type) up to 1.4 t/h.
