Effects of New Drainange/ Retention/ Formation Technolgy for Improving Production Rates and Runnability of Recycled Fiber Cylinder Machines, 1996 Papermakers Conference Proceedings

Multi-vat cylinder paper machines typically manufacture recycled paperboard from a wide variety of recycled fiber sources. These cylinder machine systems operate under a high degree of water closure, which can lead to a variety of operating problems. A wet end chemical program has been developed which allows these systems to improve production rates and runnability without changing the incoming fiber mix. This system uses a high molecular weight cationic dispersion or emulsion polymer in combination with a modified natural polymer, both of which are water soluble. Application of the new drainage/retention/formation chemistry does not require any change in operating conditions and does not involve any mechanical modifications to the paper machine. The results from usage of these additives on a cylinder-type paper machine are presented, and the machine operation improvements, both short and long term, are detailed. Long term use of the new additive program has lead to machine speed increases of 6 to 8 %, and reductions of operational downtime of 13 to 25 %, with both parameters being grade dependent.