A method of forming a fiber body includes defibrating a raw material in air to provide fibers; depositing the fibers in air onto a belt; applying pressure to the deposited fibers to form a pressurized web; and applying a liquid containing an additive to two surfaces of the pressurized web.

A processing apparatus includes a powder material supply portion that supplies a powder material containing a first particle group consisting of a plurality of first particles, and a second particle group consisting of a plurality of second particles and having an average particle diameter larger than that of the first particle group, to a fiber-containing material containing a fiber during or after defibrating, and a powder material removing portion that removes at least a portion of the powder material from the fiber-containing material supplied with the powder material. It is preferable that the processing apparatus include a defibrating portion that defibrates the fiber-containing material on an upstream side of the powder material supply portion.

A processing apparatus includes a powder material supply portion that supplies a powder material containing a first particle group consisting of a plurality of first particles, and a second particle group consisting of a plurality of second particles and having an average particle diameter larger than that of the first particle group, to a fiber-containing material containing a fiber during or after defibrating, and a powder material removing portion that removes at least a portion of the powder material from the fiber-containing material supplied with the powder material. It is preferable that the processing apparatus include a defibrating portion that defibrates the fiber-containing material on an upstream side of the powder material supply portion.

Variation in the thickness of accumulated material is suppressed when material containing fiber is dispersed by the sieve and accumulated. A sheet manufacturing apparatus includes a drum that sieves defibrated material containing fiber, a first web former that accumulates first screened material discharged from the drum, and a processor that processes a first web accumulated in the first web former. During processing by the processor, the mesh belt operates at a first speed. When operation starts with the drum not operating, a startup operation including the mesh belt operating at a higher speed than the first speed in a first period after the drum starts is executed.

Variation in the thickness of accumulated material is suppressed when material containing fiber is dispersed by the sieve and accumulated. A sheet manufacturing apparatus includes a drum that sieves defibrated material containing fiber, a first web former that accumulates first screened material discharged from the drum, and a processor that processes a first web accumulated in the first web former. During processing by the processor, the mesh belt operates at a first speed. When operation starts with the drum not operating, a startup operation including the mesh belt operating at a higher speed than the first speed in a first period after the drum starts is executed.

A web manufacturing apparatus includes a transport section configured to transport a web containing fiber, a web humidifier configured to humidify the web, and a control section configured to control operation of the transport section and the web humidifier. When transportation of the web by the transport section is stopped, the control section causes the transport section to recommence transportation of the web after the web is humidified by the web humidifier. The control section may also cause the web humidifier to stop humidification of the web after the web humidifier starts humidification of the web and a predetermined duration elapses.

A hopper includes a receiving member having a guide surface that guides a non-flat strip-shaped sheet and a posture adjusting unit that adjusts a posture of the falling sheet and sends it to the guide surface, and a discharge unit that discharges the sheet. The posture adjusting unit may have a posture adjusting surface continuous with the guide surface and bent from the guide surface so as to form a ridge line at a boundary portion with the guide surface.

A hopper includes a receiving member having a guide surface that guides a non-flat strip-shaped sheet and a posture adjusting unit that adjusts a posture of the falling sheet and sends it to the guide surface, and a discharge unit that discharges the sheet. The posture adjusting unit may have a posture adjusting surface continuous with the guide surface and bent from the guide surface so as to form a ridge line at a boundary portion with the guide surface.

A cleaning apparatus includes a cleaning roller configured to rotate about a first rotation axis to clean a component to which paper dust is attached, the cleaning roller having a first area and a second area that is adjacent to the first area in a direction along the first rotation axis and to which more paper dust is attached than to the first area, and a remover configured to rotate about a second rotation axis extending in a direction different from the first rotation axis and configured to come in contact with at least a portion of the second area to remove the paper dust from the second area.

A humidifying device includes a circulation path through which air circulates, an intake section that is provided in the circulation path and takes the air into the circulation path, a blower section that is provided in the circulation path and generates an air flow in the circulation path, a humidifying section that is provided in the circulation path and humidifies the air in the circulation path, and a discharge section that is provided in the circulation path and discharges the humidified air which is humidified by the humidifying section from an inside of the circulation path, and the circulation path has a pipeline for returning the humidified air that has not been discharged from the discharge section upstream of the blower section.