Newsprint and Improved Quality
High-speed presses demand flat profiles and superior roll conditions
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Raising the edge moisture by 3 - 4% and the reel moisture by 1.5 - 2% reduces fiber cost, improves efficiency, calender control, dimensional stability and roll building on the winder. The leveling of the moisture profile allows removal of compensating process conditions such as press crown and loading, and an uneven fiber profile that are commonly used to improve the moisture profile and reel building. The introduction of the VIB air-atomized VIB AirTech spraydampening system provides papermakers with a solution for improving their moisture profiles. The proprietary VIB Particle Size Management (PSM) technology optimizes the droplet size and allows for usage near the dry end of the process. PSM ensures uniformity in absorption and the ability to raise the moisture level by 3 - 4% in a single application. |
Achieving this level of moisture increase upstream in the first few dry sections requires as much as 5 times the volume of water used at the dry end. This volume of water addition will often relax the web and result in dryer wrinkles. Additionally, with today's common usage of recycled fiber, this level of water addition will weaken the sheet, causing sheet breaks and runability problems. The results achieved using VIB technology are quite dramatic. The profile variation (2-sigma) is typically reduced by 60 - 90% with an increase in the average moisture target at the reel. Once achieved, this performance must be maintained full time. The SprayTech system design has all electric/electronic components contained in a controlled environment enclosure located away from the harsh environment. There are no moving parts on the sprayboom. This creates a virtually fail-proof system that can be relied on to deliver performance on every ton of paper produced. Page |
