Process and apparatus for heating solid materials containing volatile matters

A process for heating solid materials containing volatile matters, in which solid materials containing volatile matters are heated in a conveyor including a substituting gas injection port, a gas bleeding port, an entrance or input side, and an exit portion with its entrance or input side being lower in level than its exit portion, comprising the steps of:

• applying heat through the periphery of said conveyor to said solid materials;
• transporting said solid materials to said exit portion of said conveyor, while being heated therein, to thereby vaporize volatile matters;
• injecting a substituting gas through said substituting gas injection port provided on the exit portion of said conveyor into said conveyor unit, said gas being lighter in weight than vapor thus produced;
• and
• purging vapor heavier than said substituting gas towards said gas bleeding port provided on the entrance side of said conveyor by utilizing a difference in gravity between said vapor and said gas, said gas bleeding port being lower than the exit portion of said conveyor, thereby preventing diffusion of vapor thus produced to preclude sticking to said materials of liquid obtained from condensation of vapor due to a lower temperature prevailing at said exit portion of said conveyor.