Slag crushing device

A slag crushing device, comprising a substantially cylindrical body having a slag insertion port in its one end and a discharge port in the other end, said cylindrical body is rotatably provided around a shaft center so inclined that the position of said discharge port is below the position of said slag insertion port, and a slag crushing portion is provided inside of said cylindrical body, the slag crushing portion comprising at least one guide frame (4C) including spaced disc-shaped bodies secured within said cylindrical body, at least one annular crushing body within said at least one guide frame, said at least one annular crushing body having a smaller radius than that of the cylindrical body and provided with an axis parallel with the shaft center of the cylindrical body such that said at least one annular crushing body can be idled, and said at least one guide frame for guiding said at least one annular crushing body having at least one inlet aperture (4B) for introducing slag into the at least one guide frame to be crushed by said at least one annular crushing body, at least one outlet aperture (4E) through which the crushed slag leaves said at least one guide frame for being transported to said discharge port, and the inlet apertures (4B) are larger than said outlet apertures (4E).