Mechanical pulp is characterized by high bulk and high light scattering and is therefore commonly used in printing and writing papers as well as in paperboards for obtaining high opacity and high bending stiffness. Due to its good water absorption properties, mechanical pulps are also used for tissue.
Mechanical pulp is produced by grinding wood chips in refiners at high pressure and temperature. The degree of refining, mild chemical treatments of chips prior to refining and peroxide bleaching is used for custom making pulp properties for a specific end use. Compared to chemical pulping the yield in mechanical pulping is very high. Between 85 and 97% of the incoming wood raw material is converted to pulp. Valmet has developed the most efficient unit processes for utilizing globally available raw materials for producing top quality mechanical pulp grades for paper and board end products. By using advanced technology in combination with over 80 years of experience in the field, Valmet supplies mechanical pulping lines that consume a minimum of natural resources such as wood, water and energy. Valmet has supplied more than 50% of the mechanical pulping installations worldwide:
• Over 150 CTMP and TMP lines with over 650 large high-consistency refiners
• Approximately 600 GW and 110 PGW grinders
• Over 50 NSSC and CMP lines.
|PGW||Pressurized groundwood pulp|
|NSSC||Neutral sulfite semichemical pulp|
Less variability and better quality with Valmet’s automation solutions
Valmet's automation solutions enable you to reduce variability, boost end product quality, lower energy consumption and reduce furnish costs in thermo-mechanical and groundwood fiber lines. Featuring Valmet’s unmatched knowledge of refining and process control, our Optimal Refining concept allows you to produce the highest pulp quality with the lowest variability. Process and pulp quality analyzers integrated with our advanced process control solutions provide you with the fiber quality and process stability required to produce pulp in the most cost-effective way while meeting the furnish quality requirements of your papermaking processes.
Customer success stories
BCTMP Art paper line consumes the least energy in the world
"We are very pleased with the new pulp line. It’s energy-efficient and very flexible. We can maneuver the line to switch from one quality to another in just 20 minutes," says the production manager at the mill