Compact, Airless Wet End System, 1999 Papermakers Conference Proceedings
Paul Olof Meinander, Lars-Hugo Olsson
A compact, airless paper machine wet end has been working on MD Albbruck Papier’s PM 7 since May 1997. The compact wet end with centrifugal deaeration was originally developed for improving the flexibility of the papermaking process. It has now proved to provide a stable and efficient, easy-to-operate process. Air removal is efficient and the system stays cleaner than before. Operating and energy efficiencies have improved. The POM Concept for a compact wet, addresses stock mixing and feeding to the machine, air removal and back water recirculation. It also proposes wet broke homogenising and recycling without thickening. A central feature is deaerating the back water by centrifugation, feeding a closed, hydraulic system without tanks. The system volume of the Albbruck installation is one seventh of the original volume. Compared to conventional design, a compact wet end requires less space and is cheaper to build. It saves energy and materials and is also is cleaner and more efficient than a conventional process. It is also a good solution for machines which do not have grade changing problems. Centrifugal deaeration can be applied for resolving capacity problems of conventional equipment.