Recycled paper

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Transport of waste paper in Japan

Recycled paper consists of recycled waste paper , cardboard and cardboard ; or the secondary fibers obtained from it. In addition to the conservation of wood reserves, the lower energy and water consumption compared to conventional paper production is advantageous .

The quality and tear resistance of the paper can be increased by selecting the types of waste paper or adding new fibers. In Germany, a product made from 100% recovered paper receives the “ Blue Angel ” environmental label . There is a tolerance of 5% for finished products .

In contrast to the production of environmental protection paper, the waste paper is bleached during processing into recycled paper ( deinking ). Since it is very time-consuming to remove the paint residues from the waste paper, recycled paper is often grayer than other types of paper. In the meantime, however, there is also white recycled paper. Depending on the desired degree of whiteness, different amounts of water and energy and, if the degree of whiteness is high, optical brighteners must be used in the production. Recycled paper made with optical brighteners does not receive a “Blue Angel”. Further differences to other types of paper result from the fibers used in production, which has an impact on the thickness and (surface) structure of the paper.

Manufacturing process

Conversion of sheets of paper into pulp

Paper recycling is usually carried out by means of a variation of the same basic process:

  1. The paper is broken down into its individual paper fibers in water, creating a thin-bodied pulp; This stage is called resuspension (re- suspension ).
  2. The aqueous slurry then goes through a cleaning process to remove non-fibrous foreign bodies. This stage often includes a wash process using chemical detergents .
  3. Sometimes a third process is added, namely the bleaching of the fibers with sodium hydroxide or sodium carbonate . To produce white paper, peroxides or hydrosulfites are used in an additional bleaching process to remove stains from the paper pulp.
  4. Finally, a “new” paper product is produced from this clean, finished fiber material, either by mixing it with primary fibers from trees in different proportions or simply by directly producing 99% recycled paper.

Conversion to paper sheets

The actual sheet creation process is then the same as with fresh fiber paper :

  1. The pulp mixture is further diluted with water, resulting in a very thin pulp. This thin-bodied mass then seeps through a fine-meshed screen section to form a fiber fabric.
  2. This moving web of fiber fabric is pressed and dried into a continuous sheet of paper.
  3. During the modeling process, a certain amount of paper pulp is placed in a mold with a wire mesh base so that the fibers form a sheet on the mesh and excess water can drain off. The paper can then be removed from the mold and begin to dry.
  4. After drying, this continuous fiber web can be cut into rectangular sheets of the desired size by cutting it vertically and horizontally.

See also

Web links

Individual evidence

  1. ↑ a b Basic criteria for the award of the eco-label for recycled paper, zip document. ( ZIP ; 827 kB) (No longer available online.) Archived from the original on April 24, 2015 ; accessed on May 26, 2015 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.blauer-engel.de
  2. ↑ Good Mengroup® GmbH & Co. KG: Steinbeis recycling office and magazine papers made from 100% recovered paper: white. In: stp.de. Retrieved May 26, 2015 .
  3. ↑ Baird, pp. 524-525; Selke, pp. 115-116.