Research Articles

Dependence curves for the kappa number of digester pulp (KN_DP), total pulp yield (TY), screened pulp yield (SY), and reject content in digester pulp (R_DP) as a function of the kappa number of screened pulp (KN_SP) were determined based on the results of several dozen kraft pulping tests of pine wood chips (Pinus sylvestris). These curves were then analyzed to assess whether their course could be used to distinguish qualitative types of pine kraft pulps and to determine the boundary values of the KN_DP, TY, SY, and R_DP indices for these types. Relationships of the form R_DP = f(KN_SP) were found to be particularly useful for this purpose. The identified types of pine kraft pulps and the limiting values of the parameters used to assess pulping process efficiency are presented in a table at the end of the paper.

Physical, mechanical, and quality characteristics of Uludağ fir (Abies nordmanniana subsp. bornmuelleriana) wood, which occurs naturally in Turkey, were determined. The effect of site classes (SCs) on these characteristics was investigated. Uludağ fir trees growing naturally in the Şerif Yüksel Forest Management District and belonging to different site classes (I, II, and III) were considered. The physical and mechanical properties of the test samples were determined in accordance with relevant standards, and differences between SCs were evaluated using statistical methods. SCs were found to have a statistically significant effect on the physical and mechanical properties of Uludağ fir wood (p<0.05). The highest performance in terms of physical and mechanical properties was generally observed in samples from Class II. Static quality (SQ) values ranged from 9.52 to 10.9, while dynamic quality (DQ) values ranged from 1.77 to 1.98. Based on DQ values, samples from all quality classes fell into the group of wood exhibiting high elastic properties; based on SQ values, they were classified as high-quality wood. The findings highlight the impact of SCs on the quality characteristics of Uludağ fir wood, providing important scientific data for quality-focused raw material selection, sustainable forest management, and the planning of wood usage areas.