Paper-Recycling System: Part 11

The fiber type of the waste paper is an important technical constraint of recycling since the properties of mechanical and chemical fibers imply different demands for paper machines. It was not possible to take this fact into account in the waste paper classification because the resources necessary to study the impact of the fiber type distinction were far beyond those available for this study.

The utilized reuse fiber potential, currently approximately 35% of all base paper and board consumption, is estimated to contain the following grades: highly printed waste paper (1) about 20%, lightly printed or unprinted waste paper (2) about 17%, composite waste paper (3) about 1%, and mixed waste paper (4) about 60%. These figures also include the estimated wastes from product manufacture.

To meet the physical property demands of the use of the paper and board products and their manufacture, there are a number of ways of modifying and furnishing the base paper or board. Recycle fibers lose some of the properties which primary fibers have. For example, re-pulping causes fibers to shorten, which, in turn, reduces strength and moisture properties.