Apparatus for producing spheroidal inorganic particulate material

An apparatus for producing a spheroidal particulate construction material comprising particles of a construction material selected from the group consisting of cement, slug and gypsum;

• the apparatus comprising a suspension preheater for preheating raw powder of said construction material, a rotary kiln for calcining the powder from said suspension preheater, a cooler for cooling the calcined construction material connected to said rotary kiln, said suspension preheater having a calcination furnace for calcining the preheated powder of said construction material at a lower portion thereof, said calcination furnace communicated to the cooler through a feedpack pipe which feeds the hot air from the cooler back to said calcination furnace, a burner which is connected to said cooler and having a nozzle which generates a high temperature flame through which the powder of said construction material is passed so that it is melted or semi-melted, an introductory portion for introducing a first exhaust gas discharged from said cooler into said burner, which is communicated to both said cooler and to said burner, and a feed pipe for feeding high temperature fine powder of said construction material preheated by said suspension preheater into the high temperature flame of said burner,
• wherein said apparatus further comprises a cyclone having a cylindrical side wall, a cooling means for cooling the construction material in the cyclone, and a flame pipe provided on said side wall, said nozzle of the burner connected to said cooler and said feed pipe for feeding the preheated high temperature fine powder of said construction material to the flame of said burner being arranged inside said flame pipe, in close vicinity to each other, the opening end portion of said feed pipe being directed toward the flame of said burner,
• wherein said cyclone has a structure so that the particles of the construction material are passed through the high temperature flame to convert them into a melted or semi-melted state and are jetted into the cyclone, thereby the melted or semi-melted particles are cooled and spheroidized.