Heat treatment system and atmosphere substitution structure of heat treatment furnace

A heat treatment system comprising:

• a first supply device;
• a first heat treatment furnace;
• a first recovery device;
• a second supply device;
• a second heat treatment furnace;
• and a second recovery device,
• wherein the first supply device is disposed near the second recovery device and configured to supply a treatment object to a saggar conveyed from the second recovery device,
• the first heat treatment furnace comprises:
• an entrance disposed near the first supply device and through which the saggar supplied with the treatment object by the first supply device is conveyed into the first heat treatment furnace;
• an exit through which the entered saggar is conveyed out of the first heat treatment furnace;
• a heat treatment unit disposed between the entrance and the exit of the first heat treatment furnace, and configured to heat-treat the treatment object supplied in the saggar while the saggar is conveyed from the entrance to the exit of the first heat treatment furnace;
• and
• a first conveyor configured to convey the saggar in a first direction, the first direction being a direction from the entrance to the exit of the first heat treatment furnace,
• the first recovery device is disposed near the exit of the first heat treatment furnace and configured to recover the treatment object that has been heat-treated in the first heat treatment furnace from the saggar,
• the second supply device is disposed near the first recovery device and configured to supply a new treatment object to the saggar from which the treatment object has been recovered by the first recovery device,
• the second heat treatment furnace comprises:
• an entrance disposed near the second supply device and through which the saggar supplied with the treatment object by the second supply device is conveyed into the second heat treatment furnace;
• an exit through which the entered saggar is conveyed out of the second heat treatment furnace;
• a heat treatment unit disposed between the entrance and the exit of the second heat treatment furnace, and configured to heat-treat the treatment object supplied in the saggar while the saggar is conveyed from the entrance to the exit of the second heat treatment furnace;
• and
• a second conveyor configured to convey the saggar from the entrance to the exit of the second heat treatment furnace in a second direction opposite to the first direction,
• the second recovery device is disposed near the exit of the second heat treatment furnace and configured to recover the treatment object that has been heat-treated in the second heat treatment furnace from the saggar,
• each of the first heat treatment furnace and the second heat treatment furnace further comprises a substitution unit disposed between the heat treatment unit of a corresponding heat treatment furnace and the exit of the corresponding heat treatment furnace, and configured to isolate the heat treatment unit of the corresponding heat treatment furnace from outside of the exit of the corresponding heat treatment furnace, and
• the substitution unit comprises doors constituted of a heat insulating material and configured to be opened and closed, and disposed between the heat treatment unit and the substitution unit of the corresponding heat treatment furnace and between the substitution unit and the exit of the corresponding heat treatment furnace.