Fibrous body processing apparatus

A fibrous body processing apparatus comprising:

• a humidifying unit that generates humidified air;
• a first processing unit that processes a material that contains fibers;
• a second processing unit that processes the material that has been processed at the first processing unit, the second processing unit including a casing with a wall in which an inlet is formed such that the material enters into the casing through the wall;
• a first supply passage through which humidified air is supplied from the humidifying unit to the first processing unit;
• a second supply passage through which humidified air is supplied from the first processing unit to the second processing unit, together with the material;
• and
• a returning passage which is an air-sending pipe through which humidified air is returned from the second supply passage or the second processing unit to the humidifying unit,
• the air-sending pipe including a downstream-side end portion and an upstream-side end portion, the downstream-side end portion being connected the humidifying unit, the upstream-side end portion being connected to the wall of the casing of the second processing unit so as to be adjacent to the inlet, or directly or indirectly connected to the second supply passage.