Process to increase the dry matter content in a wet paper web by exposure to microwave energy

摘要

In a papermaking process a fibrous suspension is discharged from a headbox onto a moving sieve on which the fibres are exposed to microwave radiation. The microwave field energy is uniform and transverse to the direction of belt advance. The field energy is directed at a fibrous web with a dry matter content of 15 to 25%. The microwave energy is in the wavelength range 1 m to 1 mm, and the frequency is about 2.45 GHz. The microwave energy is emitted by an antenna array. Also claimed is a commensurate papermaking sieve and papermaking assembly.