Hebei Messi Biology Co., Ltd. said that a slurry magnesium hydroxide can be used in pulp bleaching operations. Magnesium hydroxide is used to replace caustic soda in Eop bleaching operations, and is reviewed and compared with the traditional bleaching process. Laboratory tests show that using magnesium hydroxide can maintain the brightness of pulp, improve slurry viscosity, and reduce COD content and production costs.
In the hydrogen peroxide bleaching process of pulp, using magnesium oxide or magnesium hydroxide instead of caustic soda can reduce the content of iron and manganese ions in the slurry. The former can be reduced to 2mg/L, the latter is 10mg/L, and the quality of the slurry can be improved. Avoid yellowing due to excessive presence of iron. At the same time, it has a buffering effect and the pH value is easy to control. If it is combined with inorganic complexing agents phosphate and silicate, the effect will be better. Application of magnesium oxide instead of ammonia in ammonium sulfite pulping operations.
The results show that using magnesium oxide as an alkaline buffer, the various indicators of the slurry can reach levels similar to those of the ammonia water method. Using magnesium oxide as a buffer pulp is easy to bleach, can promote delignification during cooking, reduce costs, reduce pollutant emissions, and is beneficial to environmental protection. Magnesium oxide can be used as a wetting agent to improve pulp deinking operations. The deinking effect is equivalent to that of caustic soda in a so-called Lamort deinking device. Field trials for pulp flotation deinking at the Fletcher Challenge Alburv paper mill showed that magnesium oxide can successfully replace caustic soda.
Hebei Messi Biology Co., Ltd. stated that the magnesium-based sulfite pulping process is an improvement on the traditional sulfite pulping process, and the chemicals and waste heat used can be recycled. In the improved process, lower quality wood can be used as raw material, and the pulp obtained can be used in the manufacture of news printing paper, providing the possibility to solve ecological and economic problems in traditional sulfite pulping operations in paper mills. Magnesium agent resources can be natural magnesium hydroxide. The pulp produced by the magnesium agent process has higher strength (especially the breaking strength) than the acid sulfite process, and the use of magnesium agent requires less investment.