Studies on Alkali-Oxygen-Anthraquinone Delignification of Bagasse, 1990 Pulping Conference Proceedings

The proposed study was undertaken to assess the suitability of bagasses by alkali-oxygen delignification process and to know the effect of anthraquinone (AQ) on pulp and paper characteristics. The loose structure and low specific gravity of bagasses makes it possible the diffusion of dissolved oxygen easier to accomplish alkali-oxygen-AQ delignification in one step without fiberization. The effects of cooking variables, like oxygen pressure (0,5,10 and 15 kg/cm2), alkali charge (8,10,12 and 15%, as Na2O), cooking time (20, 30, 45 and 60 minutes), cooking temperature (130, 140, 150 and 160 „aC) bath ratio (1:5, 1:6 and 1:7) and AQ dose (0, 0.05, 0.1, 0.2 and 0.5%), on pulp yield Kappa number, screening rejects and strength properties were evaluated. The alkali oxygen-significant increase in screened pulp yield and rate of delignification, compared to soda and soda-oxygen pulping, due to stabilization of carbohydrates towards end wise degradation. These process variables were also optimized. Based on experimental results, it can be concluded that the optimum set of process parameters. To get better quality pulp with improved strength properties are: Alkali 2 dose – 10% (as Na2O), oxygen pressure – 5 kg/cm2, temperature - 140„aC, Time – 30 minutes, bath ratio – 1:7 and AQ dose – 0.1%.