Device for dewatering a material web

摘要

Apparatus and process for dewatering a material web. The apparatus includes at least one pressure chamber formed by at least four substantially parallel rolls, a device arranged to introduce a pressurized gas into the at least one pressure chamber, and the at least four substantially parallel rolls being displaceable relative to one another to change an effective area of the at least one pressure chamber. The material web is guided through the at least one pressure chamber. The process includes pressurizing at least one pressure chamber with a gas medium, guiding the material web through the pressure chamber, driving water out of the material web using gas pressure within the at least one pressure chamber, and changing an effective area of the pressure chamber so as to adjust a dewatering capacity.