Editing Kraft process (section)

===Screening===
Screening of the pulp after pulping is a process whereby the pulp is separated from large [[Shives (papermaking)|shives]], [[Knots (papermaking)|knots]], dirt and other debris. The ''accept'' is the pulp. The material separated from the pulp is called ''reject''.

The screening section consists of different types of [[sieve]]s (screens) and centrifugal cleaning. The sieves are normally set up in a multistage cascade operation because considerable amounts of good fibres can go to the reject stream when trying to achieve maximum purity in the accept flow.

The fiber containing shives and knots are separated from the rest of the reject and reprocessed either in a refiner or is sent back to the digester. The content of knots is typically 0.5–3.0% of the digester output, while the shives content is about 0.1–1.0%.