Study of the Influence of Dissolved and Colloidal Components on Paper Sizing by Simulation of Process Water Loop Closure

Nejc Zakrajšek,^a* Janja Zule,^a Adolf Može,^a and Janvit Golob^b
a Pulp and Paper Institute Ljubljana, Bogišičeva 8,1000 Ljubljana, Slovenia, E-mail: nejc.zakrajsek@icp-lj.si
^b Faculty of Chemistry and Chemical Technology, Aškerčeva 5, 1000 Ljubljana

Abstract
Simulation of process water loop closure in a papermaking system was performed on laboratory scale by means of the Rapid-Köthen sheet former. The concentrations of sulphate and dissolved inorganic ions, expressed as conductivity, as well as the concentration of dispersed rosin size Sacoccel 309 were systematically measured during the process. The influence of increasing concentrations on paper sizing efficiency was the main objective of our research. Therefore, we determined the highest degree of water closure at which the examined dissolved and dispersed components do not negatively interfere with the paper sizing process yet.

Key words: paper sizing, water loop closure, simulation