JPS6247500B

PURPOSE:To obtain a product having a high inflation degree, by heat-treating a powdery or granular substance with saturated steam under pressure, subjecting it to pressure treatment with high-temperature heated steam. CONSTITUTION:The heating apparatus 1 of the screw conveyor type consists of the horizontal and cylindrical pressure container 2 and the screw 3 set in the container 2. The pressure container 2 is equipped with the feed opening 4 for a raw material and the outlet 4' for the raw material. The heating can 8 of the pressure type is provided with the feed opening 9 for the raw material and the outlet 10 for heating steam at the top of the heating can, and with the outlet 12 for the raw material and the inlet 11 for superheated steam at its bottom. The outlet 12 is equipped with the discharge valve 13, the feed opening 9 for the raw material is communicated and connected to the outlet 4' for the raw material of the heating apparatus 1 of the screw conveyor type. The heating can 8 has a great number of the venting holes 14 in it, the porous plate 15 on which the raw material is piled is set horizontally, the porous plate 15 is partially equipped with the dropping hole 16, which is connected to the outlet 12 for the raw material.