Gas Control

Gas content is an important wet-end stability parameter influenced by both mechanical and chemical deaeration.

Why gas control matters

Pulp and paper suspensions contain gas in two forms: free (entrained) gas and dissolved gas. Excess gas can disturb stock flow, retention, drainage, and foam control, creating variability throughout the wet end.

As gas levels fluctuate, the efficiency of retention, fixation, and dewatering processes may become less consistent. This can affect filler distribution, sheet formation, ash retention, and internal sizing performance, leading to variation in sheet properties and overall product quality.

On grades where visual appearance and print performance are critical, this same variability can also surface as inconsistent opacity, brightness, absorbency, and print uniformity, since fine fillers such as PCC, GCC, clay, and titanium dioxide are highly retention-sensitive to changing gas levels.