Study on Alkali-Oxygen Pulping of Bagasse Wet-Stored with Hypochlorite Bleaching Waste Water

Abstract

In this paper, the bagasse wet-stored with hypochlorite (H) bleaching waste-water which was the original waste liquid from H bleaching process of bagasse, was cooked with alkali-oxygen and its pulping effect was studied. The results showed that the proper treatment time of wet storage with H bleaching waste-water was 12 days, the pulping properties were as follows: screened pulp yield 62.9%, kappa number 15.4, viscosity 802 mL/g, and brightness 58.8 %ISO. The strength properties of pulp were as follows: tensile index 65.6 N•m/g, tear index 5.86 mN•m2/g, burst index 3.83 kPa•m2/g and folding endurance 302 times. In addition, the pulping properties of bagasse wet-stored with H bleaching waste-water were similar to those of bagasse wet-stored with fresh water. Therefore, it can be concluded that the H bleaching waste-water could be used as spraying water for wet storage of bagasse. It was a new idea for saving fresh water in the pulping and papermaking industry.