| 摘要 |
A method of continuous drying of a paper or other porous web by passing the web (3) by means of a drying felt or wire (4) between two moving, air-impermeable surface elements (1, 8) having good heat conducting properties, which elements enclose the web along its whole width. The surface element (1) contacting the web is heated and the surface element (8) contacting the wire is cooled for evaporating water present in the web and condensing the evaporated water into the felt or wire. The temperature of the liquid used for cooling the surface element to be cooled is maintained above 100 DEG C. and the pressure at least at such a level as to prevent the liquid from boiling. Thus, the drying of the web can be carried out at an elevated temperature and under an elevated pressure in a continuous process at production conditions for improving the web characteristics. Preferably the cooling liquid is maintained at different temperatures and/or under different pressures at separate steps of the cooling process. Thus, it is possible to adjust the drying conditions affecting the web characteristics. The device for carrying out the method is provided with a cooling space (11) divided into at least two separate cooling liquid compartments positioned one after the other in the direction of movement of the surface elements (1, 8), said compartments containing cooling liquids having different temperatures and/or pressures, the temperature of at least one cooling liquid being above 100 DEG C.
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