FÖRFARANDE OCH ANORDNING FÖR BEHANDLING AV EN FIBERBANA

摘要

The plant for treating fibrous web (W), comprises spraying boxes (19) having a spraying chamber and a spraying nozzle for spraying a treatment liquid on the surface of the fibrous web in a direction of movement of the fibrous web before a nip formed by two nip elements (11) equipped with a movable surface, the nips, and means for pressing the fibrous web in the nip after the application of a treatment agent, and first spraying boxes that are provided together between the spraying chamber having a first nip element (12) and a second nip element. The plant for treating fibrous web (W), comprises spraying boxes (19) having a spraying chamber and a spraying nozzle for spraying a treatment liquid on the surface of the fibrous web in a direction of movement of the fibrous web before a nip formed by two nip elements (11) equipped with a movable surface, the nips, and means for pressing the fibrous web in the nip after the application of a treatment agent, and first spraying boxes that are provided together between the spraying chamber having a first nip element (12) and a second nip element. The fibrous web is provided for supporting at the moving surface of the first nip element during the spraying of the treatment liquid. The spraying box comprises a discharge device (5) for discharging an air and/or treatment agent mist from the spraying chamber. The nip element comprises a roller, a belt, a sieve, a combination of the roller and the belt, a combination of the roller and the sieve, or a corresponding pressing element that has the surface to be moved into the nip against the fibrous web. The discharge device has a suction box. The plant further comprises second spraying boxes whose spraying chamber guided to the nip, is arranged between freely supported surface of the fibrous web and the surface of the nip element and the second spraying box. The plant has a limiting device for a flow that is arranged between the first and/or the second spraying box, and the nip element is not involved on the support of the fibrous web for limiting the air- and treatment agent mist flow between the spraying chamber and an outside of the spraying chamber. The limiting device is attached at an edge of the suction box associated with a suction opening (6), which is externally viewed by the direction of the spraying chamber. The limiting device has a joint or a hinge or a spring or elastic material. The spraying nozzles are arranged in the first and/or second spraying boxes on a side of an inlet of the fibrous web leading to the spraying chamber. The nip element is treated/coated or after a method preventing an inherence of the fibrous web. The nip element is heated. The spraying box is arranged in connection with the nip of a roller system (30) in wetstack-calender such as a water tank. An independent claim is included for a method for treating a fibrous web.