| 摘要 |
The invention relates to a method for drying a fibre-based pulp web (2), and to a drying box (1) used in the method. According to the invention, the dryi ng box (1) contains drying zones (9a-9e), to each one of which hot drying air c an be blown independently so that the web can be dried in the various zones at different temperatures. The temperature of the first zone (9a) can thus be lower than that of one or more subsequent zones (9b-9e) to prevent the water in the incoming wet web from boiling. The last zone in the drying box (1) ca n be a separate cooling zone (11), wherin the web is cooled by indoor air from outside the box. The temperatures can be adjusted by adjusting, with the aid of valves (8), the pressure of the steam, which heats the drying air that is fed into the various ones (9a-9e), on the basis of the temperatures measured by the sensors (23) for the various zones and of the basis weight and moistu re measurements carried out on the web (2) that goes into the box (1) and comes out of the box.
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