PURPOSE: To produce a stable particle agglomerate by atomizing liquid in a drying chamber by an atomizer wheel to form liquid droplets, recovering the finest fractions in the dry matter of the liquid droplets, recirculating the fractions into the drying chamber by an air effect and bringing the fractions into collision against the ejected liquid droplets.

CONSTITUTION: The liquid (e.g. concd. whole milk) supplied from a conduit 4 is atomized to form the liquid droplets in the drying chamber 3 by the atomizer wheel 5 and the dry air stream enclosing the wheel 5 is guided mainly to a traversing direction of their passages for the ejected liquid droplets. As a result, the liquid droplets are dried and a granular material is prepd. The finest fractions of the particles of the material are recovered by cyclones 11, 19 and are recirculated to the drying chamber 3 via a pipe 20 by the air effect and are brought into collision against the slight tacky adhesive particles of the ejected liquid droplets or only the partially dried particles. As a result, the stable production of the particle agglomerates having a desired structure, grin size and strength is made possible.