Introduction
The Centrifugal Spray Dryer is the technology most widely used in
the liquid technology shaping and in the drying industry. The
drying technology is the most suitable for producing solid powder
or particle products from liquid materials, such as: solvent,
emulsion, suspension and pumpable paste states, fro this reason,
when the particle size and distribution of the final products,
residual water contents. Mass density and the particle shape must
meet the precise standard, spray drying is one of the most desired
technology.
Application
Food industry
Fat-rich milk powder, sorghum, cocoa milk powder, milk replacer
powder, egg white (yellow), food and plant juice, Oatmeal, chicken
juice, coffee, instant tea, flavorings, meat, protein, soy, peanut
protein, hydrolysate, etc.
Carbohydrate
Corn syrup, corn starch, glucose, pectin, maltose, etc.
Plastic resin
AB, ABS emulsion, urea resin, phenolic resin, dense (urea)
formaldehyde resin, polyethylene, polyvinyl chloride and the like.
Chemical industry
Sodium fluoride (potassium), basic dye pigments, dye intermediates,
compound fertilizers, formaldehyde silicic acid, catalysts,
sulfuric acid agents, amino acids, white carbon black, and the
like.
Ceramics
Alumina, ceramic tile material, magnesium oxide, talcum powder.
Advantages
1. Particle size control
The dry particle size can be easily controlled by atomization of
the liquid feed and the design of the hot gas inlet. This spray
dryer can typically produce between 30 to 500 micron average
particle size, in a bell shaped distribution.
2. The evaporative cooling of product
The heat and mass transfer during drying occurs in the air and
vapor films surrounding the droplet. This protective envelope of
vapor keeps the particle at the saturation temperature. As long as
the particle does not become "bone-dry", evaporation is still
taking place and the temperature of the solids will not approach
the dryer outlet temperature.
3. Short residence time
The surface area produced by atomization of the liquid feed enables
a short gas residence time, ranging from 3-10 seconds depending
upon the application, which permits spray drying without thermal
degradation.
4. Flow properties of dry product
The shape of most spray dried particles is spherical, which
provides for fluid-like flow properties. This makes many downstream
operations, such as packaging, pressing, filtering, and handling
easier and less costly.
5. Size design of drying chamber
The size of drying chamber is specially designed to prevent
droplets sticking to the inner wall, dried powder accumulating on
the cone part and guarantee enough residence time.
