PURPOSE: To perform drying in good efficiency, by spraying a stock liquid in which a gasifiable material is premixed into a tower.

CONSTITUTION: A stock liquid 6 is supplied to a supply pipe 8 by a plunger pump 7 while a gasifiable material such as soluble or liquified gas, for example, carbon dioxide or ammonia is supplied to a supply pipe 11 from a gasifiable material tank 9 through a plunger pump 10 and both of them are sprayed in a mixed state from an atomizing nozzle 2. In this case, the gasifiable material is abruptly gasified to make it possible to further comminute sprayed particles by its expansion force and, because the contact area thereof with hot air which is supplied from a hot air supply port 3 and exhausted from a central outlet 4, drying efficiency is enhanced.