A 10-day mill trial of near-neutral sulphite deinking part III: Overall mill assessment

During a 10-day mill trial of near-neutral sulphite deinking, PM5 ran with 34% DIP with exceptional, unprecedented runnability. Even if slightly lower (1-3%) paper-to-paper coefficients of friction of the newsprint paper containing various percentages of sulphite DIP were measured, no negative customer feedback was obtained. Accelerated concrete corrosion from the news train due to sulphite deinking is unlikely. No significant increase in microbiological activity was noted in the recycle furnish. At the end of the trial, the results indicated a healthy, stable activated sludge biomass.