Single stage spray dryers offer particle sizes of dried material from 50-250 microns. For producing large particles Fluidized Spray Dryers are employed. The atomization of the feed solution is done to produce large droplets and the drying in the first stage is done keeping the moisture content of the powder relatively high. The moist powder is dried in the integrated fluid bed system at the bottom of the drying chamber using hit air, and in the process, agglomeration of fines to larger particles takes place. The absolute fines are carried with the exhaust air leaving the drying chamber to be collected in the cyclone and further recalculated to the drying chamber. Tertiary drying systems comprise of employing additional external drying system to further increase the particle size. Shown in the layout is one of such system incorporating a fluidized spray dryer with vibratory fluid bed drier.