|Spray dryer is a device that obtains dry products in particle or granular form from the liquefied raw material such as solution or slurry by one effort. The crude liquid is prayed by the revolving disk or nozzle, and the liquid drop made by spray into particles instantaneously contacts hot air that flows in the same direction(co-current), the reverse direction(counter-current), or the same and reverse direction(mixed flow). As the moisture evaporates rapidly, the liquid drop keeps low temperature and even the rise of dry air temperature does not affect the property of the product at all. Application of such a spray drying method may omit many processes such as concentration, filtration, grinding, classification and granulation, which in the end can simplify the processes and thus reduce the cost required for facilities. Size and operating conditions of dryers should be selected individually depending upon the characteristics of each product. Due to such characteristics, the spray dryer has been actively introduced to and widely used in various fields of fin chemical industry including dyestuffs and pigments and electronic part industry as well as food industry, chemical industry and medical supplied industry as a means of rationalizing the production and enhancing the product quality.