Method for treating a filtrate produced from a paper fiber suspension of waste paper comprises adding the filtrate partly to the paper fiber suspension at a site lying downstream of a thickening units from which the filtrate is produced

摘要

Method for treating a filtrate (F3, F6) produced from a paper fiber suspension (S, S~) of waste paper comprises adding the filtrate partly to the paper fiber suspension at a site (10, 11) lying downstream of a thickening units (3, 6) from which the filtrate is produced. Preferred Features: The filtrate is fractionated before being added so that a material concentrate (13) and a clear filtrate (14) are produced. The material concentrate is added at a site downstream of the thickening units.