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(11) | EP 0 653 514 A3 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Process and apparatus for drying sheet materials |
| (57) An apparatus and method for drying a wet sheet material such as a paper web is presented.
The apparatus is provided with a suitable number of dryer cylinders operating in conjunction
with a plurality of steam blast ports disposed adjacent to the dryer cylinders. A
vertically movable canopy hood and a middle hood having sheet entry/exit opening and
a door opening device are provided. The wet sheet material is held between two endless
fabric belt, and passed through the dryer cylinders alternatively by means of suction
fabric rolls, fabric rolls and fabric tension rolls. The drying process is carried
out in an atmosphere of superheated steam of over 100°C inside the canopy hood and
the middle hood, and the steam generated from the wet sheets is recirculated through
an exhaust screen, a super heated steam circulating fan, an adiabatic compressor and
a supply duct. Another atmosphere of heated moist air having a dew point of at least
80°C is also employed. The dried paper product manufactured has high dimensional stability
and exhibits superior printing characteristics and substantially increased paper strength,
and the process is highly energy conserving. |