On the paper machine, paper is produced out of processed plant fibers (mechanical, chemical pulp, recycled fibers). At first fibers are distributed in water, pre-treated, mixed with other raw materials and - after further dilution and making the water/fiber mixture as uniform as possibly - introduced to the headbox. From there, this suspension is brought to the wire where sheet forming and the first step of dewatering takes place. Further dewatering steps are carried out in the press section and the drying section. In the water circuit of the paper machine the major amount of water used for paper making is recovered.