Heat treatment device

A heat treatment device utilizing heat exchange between a first fluid and a second fluid, the device comprising:

• a first heat transfer body including a first flow channel through which the first fluid flows;
• a second heat transfer body including a second flow channel through which the second fluid flows, the second heat transfer body being stacked on the first heat transfer body;
• and
• a casing having a space communicating with one end of the second flow channel, the casing being in contact with a surface including an edge of a connection interface between the first heat transfer body and the second heat transfer body,
• wherein
• the first heat transfer body and the second heat transfer body are plate-like members having a first side surface, a second side surface being the opposite of the first side surface, a third side surface being perpendicular to the first side surface, and a fourth side surface being the opposite of the third side surface, and the first side surface, the second side surface, the third side surface, and the fourth side surface are perpendicular to the connection interface, respectively,
• the first heat transfer body further includes a wall portion between the first flow channel and the space of the casing, the wall portion forming a third flow channel independent of the first flow channel,
• the first flow channel is in contact with the connection interface, the first flow channel having three inner surfaces constituting a first groove formed in the first heat transfer body and one inner surface being a part of the second heat transfer body facing the first groove in the first flow channel,
• the second flow channel has three inner surfaces constituting a second groove formed on a surface opposite to the connection interface in the second heat transfer body,
• the third flow channel is in contact with the connection interface, the third flow channel having three inner surfaces constituting a third groove formed in the first heat transfer body and one inner surface being a part of the second heat transfer body facing the third groove in the third flow channel, and the third flow channel intersecting with a virtual line connecting the first flow channel with the space of the casing at the connection interface,
• one end of the first flow channel is opened from the first side surface of the first heat transfer body,
• the other end of the first flow channel is opened from the third side surface or the fourth side surface of the first heat transfer body,
• the one end of the second flow channel is opened from the second side surface of the second heat transfer body,
• the other end of the second flow channel is opened from the third side surface or the fourth side surface of the second heat transfer body, and
• at least one end of the third flow channel is opened from one of the third side surface or the fourth side surface of the first heat transfer body.