Problem Summary

Deposition in the dryer section of Newsprint machines often increases downtime due to holes, breaks, clean-up, winder runnability problems, and clothing changes.  Dirt, holes, and stickies negatively impact the value of Newsprint.  Frequent splices and patches required to remove these defects can also reduce it's value.  In addition, snowing, flakes, picking, and linting negatively impact the print quality of Newsprint.

Deposition can take many different forms, ranging from a thin, invisible film on dryer cylinders that causes sheet picking, fiber rising, and linting to much thicker, visible deposits on both dryer cylinders and dryer fabrics.  If the deposit is located on the dryer cylinder, it can act as a thermal insulator.  If the deposit is located on the dryer fabric, it can impair moisture removal.  Reduced productivity and/or an uneven moisture profile are the result of such deposits.

Newsprint producers often reduce the temperature of the first few dryer cylinders in order to gradually heat the sheet, which reduces thermal shock and decreases the deposition rate.  However, this reduces production capacity.

Recommended Solution

Zenix® Dryer Section Passivation Technology combines chemistry, equipment, and application expertise to eliminate deposition and significantly reduce linting in the dryer section of a Newsprint machine.  This exclusive technology, which employs the continuous application of chemistry directly onto either dryer cylinders or dryer fabrics, establishes a protective coating on the treated surface that prevents contaminant adhesion.  The resulting surface passivation not only prevents deposition but also reduces linting by improving the release of the sheet.

Key benefits recorded from practical applications of Zenix® Dryer Section Passivation Technology include:

Eliminated/reduced deposition
Reduced picking and linting
Fewer breaks
Improved moisture profile
Improved sheet smoothness
Reduced steam consumption