Deinking in a large deinking pulp mill

Haindl Papier is among the largest users of recovered paper for the production of wood containing printing paper grades. At Schongau Haindl operates one of the largest single line deinking pulp mills of the world, using 1900 mt/d recovered paper. The mill uses mainly recovered paper from household collections which contains an about equal amount of ONP and OMG mixed with catalogues, flyers and other printed products. The quality of the recovered paper has been deteriorating during the last years because of a higher recovery rate, decreasing paper basis weight, higher printing ink coverage and more heatset offset printing. On the other hand the deinked pulp (DIP) is not only used for the production of standard newsprint but also for improved newsprint and SC-B,grades with an ash content of 30 % using 80 to 100 % DIP. High brightness and a good degree of cleanliness are required for a good paper quality. The mill has tried to offset the deterioration of the recovered paper quality by adding better and new equipment for an efficient removal of the printing ink and has achieved a good quality level. The technology used has also a good reputation for a very good rate of removal of stickies as shown by the very efficient production figures of the three paper machines operated at Schongau.