Thermal treatment apparatus

A thermal treatment apparatus comprising:

• a thermal treatment furnace having a vertical reaction tube forming a thermal treatment region therein and provided with a furnace entrance capable of being opened and closed to allow conveying in and out of objects to be treated;
• a treatment gas introduction pipe provided in an interior of said reaction tube for introducing a treatment gas into said thermal treatment region and having at an upper end thereof a treatment gas introduction port for generating an upwardly directed flow of a treatment gas directed toward an upper portion of said reaction tube through said thermal treatment region within said reaction tube, said upwardly directed flow of treatment gas performing a thermal treatment with respect to an object to be treated within said thermal treatment region;
• a purge gas introduction pipe positioned at a lower portion of said reaction tube and below said treatment gas introduction port, and on an upstream side with respect to said upwardly directed flow of treatment gas emitted from said treatment gas introduction port, for introducing a purge gas directed upward within said thermal treatment region;
• and
• a purge gas throttle mechanism provided between said thermal treatment region and said purge gas introduction pipe, for accelerating said purge gas introduced from said purge gas introduction pipe, thus generating a counterflow in a direction opposite to a direction of diffusion of said treatment gas, at a speed faster than a speed at which said treatment gas introduced from said treatment gas introduction port into said thermal treatment region diffuses towards said furnace entrance, in order to prevent said treatment gas introduced into said thermal treatment region from intruding into said furnace entrance.

A thermal treatment apparatus comprising:

• a thermal treatment furnace having a vertical reaction tube and provided in a lower portion thereof with a furnace entrance capable of being opened and closed to allow conveying in and out of objects to be treated, said reaction tube having an outer tube open at a lower portion and an inner tube provided within said outer tube, which forms a thermal treatment region therein and is also open at both upper and lower portions, and which forms together with said outer tube an annular space;
• a treatment gas introduction pipe provided within said inner tube to introduce a treatment gas into said thermal treatment region and having at an upper end thereof a treatment gas introduction port for generating an upwardly directed flow of a treatment gas directed toward an upper portion of said inner tube through said thermal treatment region within said inner tube;
• a purge gas introduction pipe positioned at a lower portion of said inner tube and below said treatment gas introduction port, and on an upstream side with respect to said upwardly directed flow of treatment gas emitted from said treatment gas introduction port, for introducing a purge gas directed upward within said thermal treatment region;
• a purge gas throttle mechanism provided between said thermal treatment region and said purge gas introduction pipe, for accelerating said purge gas introduced from said purge gas introduction pipe, thus generating a counterflow in a direction opposite to a direction of diffusion of said treatment gas, at a speed faster than a speed at which said treatment gas introduced from said treatment gas introduction port into said thermal treatment region diffuses towards said furnace entrance, in order to prevent said treatment gas introduced into said thermal treatment region from intruding into said furnace entrance;
• and
• an exhaust system connected to an upper portion of said outer tube.