To provide a device which loads a high-viscosity or high-moisture raw material to be crushed and dried in a fluid crushing and drying device with a material reducing the viscosity or an additive reducing the moisture content between a raw material charging opening, the starting point of conveying the raw material, and a discharging opening, the end point of conveying the raw material to mix, stir, and convey a mixture to the fluid crushing and drying device while controlled as a mixing and stirring material of a low viscosity or low water content.

A mixing and stirring mechanism arranged in a conveying passage in which the raw material and the additive are mixed and stirred is constituted in such a way that mixing and stirring blades exhibiting a returning function are arranged in combination with mixing and stirring blades exhibiting a feeding function.