New Cationic Polymers for Enhanced Runnability and Paper Quality in Closed Water Systems, 2001 Papermakers Conference Proceedings

Antonius Moormann-Schmitz, Anton Esser--Problems associated with closing water systems have been described in numerous publications over the last years. The increased usage of recycled fibers, mechanical pulps and higher coating weights as well as the increased machine speeds have challenged the papermaker to come up with improved treatment strategies. The chemical nature as well as the physical properties of the interfering substances have to be clearly understood to develop a sufficient treatment concept. Colloidal dissolved material, rosin pitch, white pitch and stickies have different behaviors in a paper machine system and therefore require tailor-made treatment strategies. In this paper we will discuss the performance of a new generation of fixing agents based on polyvinylamine (PVAm) and modified polyethylenimine (PEI). Results from lab experiments and mill studies indicate that these new polymers can have a significant impact on paper machine runnability and paper quality. The overall process efficiency will be supported by an enhanced performance of other wet end chemicals in use.