Removing Impurities Instead of Dispersing, 1999 Recycling Symposium Proceedings
Timo Ala-Jääski
Ahlstrom Machinery Corporation
Mills using recovered paper are continuously looking for savings either in utility consumption or in raw material costs. The consumption of electrical energy is one of the main costs. Dispersion units have a very high consumption but they used to be a must in order to meet the quality demands. This paper presents mill experience of replacing a dispersion unit with a slotted screening system consuming one third of the original electrical power.
Another important issue is the cost of raw material. Paperboard makers throughout the world are looking for ways to replace the more expensive sorted recovered paper grades with cheap unsorted mixed papers. Replacing the dispersion with slotted screening has given that opportunity to several European mills.
Income is as important as the costs, and the end product quality has proven the equality of these two systems.
Removing Impurities Instead of Dispersing, 1999 Recycling Symposium Proceedings