Modern Groundwood Pulping Systems in LWC and SC Grades, 1991 Pulping Conference Proceedings

Groundwood Printing Papers represent the most efficient use of the forest resource for fine paper manufacture in terms of yield, and the high scattering coefficient of the mechanical pulp component provides high opacity at relatively low grammage. These grades are primarily used in advertising printing and have enjoyed very healthy demand growth in the last 10-15 years. This trend is expected to continue in this decade with emphasis placed on high quality, high value added, and market segmentation/diversification. Groundwood technology modernization utilizes the unique quality characteristics of groundwood pulp and focuses on advances in control systems to reduce manpower requirements and increase pulp quality uniformity. The development of the pressurized groundwood process has played a significant role in the return to respectability for groundwood. PGW offers significant strength improvements over SGW without sacrificing optical properties or increasing energy requirements. This presentation reviews the start-up and operating experience of mills that have installed modem groundwood systems and focuses on the pulp quality improvements associated with these technological upgrades.