PULPING POTENTIAL OF DOUGLAS FIR (Pseudotsuga menziesii Mirb. Franco)

Abstract: Wood is a natural composite of strong cellulose fibres embedded in a lignin matrix that is resistant to compression. It is a complex material, serve as raw material for many chemical products, including pulp and paper. The pulp properties of Douglas fir wood were examined in this study to meet the need of wood for paper production in order to reduce overexploitation of the most used species. Wood samples obtained from a 9-years old tree were chipped for the pulp experiment using the Kraft pulping method. The experiment was subjected to usage of two different alkali charges (NaOH 15% and 17%) and three sulphidity levels (Na2S 23%, 25% and 27%). Data were analysed using descriptive statistics and ANOVA at α0.05. The results show that the highest pulp yield of 51.41% was obtained in this study under active alkali of 15%, sulphidity of 27%, time of 190 minutes and temperature of 170oC. A strong negative correlation coefficient of -0.936 was observed between kappa number and pulp yield. Generally, the pulp properties observed in this study indicated the suitability of Douglas fir for paper production as it has produced high yield and a good pulp quality.