Process and apparatus for removing water from fibrous web using oscillatory flow-reversing air or gas

Abstract

A process and an apparatus for removing water from a fibrous web are disclosed. The process comprises providing a fibrous web having a moisture content from about 1% to about 99%; providing an oscillatory flow-reversing impingement gas having a pre-determined frequency; providing a gas-distributing system comprising at least one discharge outlet designed to emit the oscillatory flow-reversing impingement gas onto the web; and impinging the oscillatory flow-reversing gas onto the web through the plurality of discharge outlets, thereby removing moisture from the web. The apparatus comprises a web support designed to receive a fibrous web thereon and to carry it in a machine direction; at least one rotary valve pulse generator designed to produce oscillatory flow-reversing air or gas; and at least one gas-distributing system in fluid communication with the pulse generator for delivering the oscillatory flow-reversing air or gas to the web. The gas-distributing system terminates with at least one discharge outlet juxtaposed with the web support such that the web support and the discharge outlets form an impingement distance therebetween.

Dependencies are inferred from the claim text.