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The Effect of H-Factor on Kappa Number and Viscosity in Continuous Digester

Rizka Wulandari Putri, Rahmatullah Rahmatullah, Faisal Siagian


One of the most important steps in pulping is the cooking process, which serves to separate the cellulose and hemicellulose from lignin and other by-products. During the cooking process in the digester, various factors must be considered to create high-quality pulp. Among these factors, the H-Factor plays a significant role due to its impact on the kappa number and viscosity in the pulping process. A high H-Factor can also damage the strength of the pulp. Therefore, this research aims to investigate the effect of the H-Factor and active alkali on pulp yield and quality. The active alkali used was in line with the desired production objectives, as insufficient levels of active alkali can lead to a low yield of pulp. Meanwhile, pulp quality standards in the Pulp and Paper Industry included kappa number of 12-18 in the digester process, an approximate viscosity of 23 mPa.s, and the selection of H-Factor based on the desired production target.


active alkali; cooking process; H-Factor; kappa number; viscosity

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