Soda-oxygen pulping of bagasse at low temperature

Soda-oxygen pulping of bagasse under a lower temperature was studied in this paper. Some effects, including the cooking curves, and soda dosages, on the pulping process were investigated. As a result, the soda-oxygen pulping of bagasse at 100 degrees C was successful. The optimized conditions were: active alkali charge of 23%, maximum cooking temperature of 100 degrees C, time to maximum temperature of 55 min, time at the maximum temperature of 180 min, initial pressure of oxygen of 0.6 M.Pa, MgSO4 charge of 0.5%, additive AOA-1 of 0.5%, and depithed bagasse consistency of 12%. Some properties of soda-oxygen bagasse pulp produced at the optimal low-temperature cooking conditions were: screened yield of 60.9%, Kappa number of 14, viscosity of 766 dm(3)/kg, and brightness of 63.7%. Compared with pulping at higher temperatures (125-110 degrees C), this pulp had higher screened yield, higher brightness, and acceptable viscosity, while the delignification degree was moderate. The experimental results indicated that this puling process is well suited for pulping bagasse. The temperature of 100 degrees C was also the lowest cooking temperature reported for Soda-oxygen pulping of bagasse till now. Pulping at a lower temperature than the conventional methods means that it can more easily be commercialized, because of its much mild operation conditions and the better pulp qualities.