METHOD FOR CHLORINE-FREE BLEACHING OF PULP WITH ACETIC ACID AS ACIDIFYING AGENT

摘要

A method of bleaching pulp of cellulosic fibre material without the use of chlorine when manufacturing chemical pulp is described, wherein the pulp entering is fed continuously in a bleaching line and is treated with a sequestering agent in the presence of an acid in order to adjust the pH to a value below 7 and is thereafter bleached in a sequence of several stages consisting of peroxide, at least one organic per-acid and peroxide. According to the invention it is suggested that in the treatment with the sequestering agent the pulp is acidified with acetic acid.