Method and apparatus for drying a hygroscopic material possessing fibrous structure

Abstract

A method of, and apparatus for, drying a hygroscopic material possessing a fibrous structure, such as wood and cardboard, which is impinged in a closed drying compartment by a flowing drying medium, which is heated and demoisturized, and wherein after the introduction of the material to be dried into the drying compartment the drying medium is heated to a predetermined temperature and maintained during the entire drying process at such temperature. The drying medium is moved past the material to be dried in order to remove from such material the expelled moisture. From the point in time of reaching the aforementioned predetermined temperature and a fixed value of the moisture content of the drying medium, calculated after the course of a certain time duration, the drying medium is demoisturized for such length of time until its moisture content has dropped to the aforementioned fixed value. And thereafter in alternate sequence there is interrupted the dehumidification or demoisturizing of the drying medium during the entire predetermined time duration from the point in time of the momentary attainment of the mentioned fixed value of the moisture content of the drying medium, and finally after expiration of the mentioned predetermined time duration the drying medium is demoisturized for such length of time until its moisture content has reached the aforementioned fixed value.

Dependencies are inferred from the claim text.