关键词: 生物质, 水解, 黑液, 水热, 硫酸盐制浆

Abstract:

The lignocellulose is treated by hydrothermal prehydrolysis technology, and the main components of the wood chips are changed, which has an impact on the subsequent chemical pulping properties and the properties of the pulping black liquor. In this experiment, Acacia wood chips were treated with different prehydrolysis strength (P-factor), and their kraft pulping behavior and resulting black liquor properties were analyzed. The results show that the yield of final pulp is reduced with the increase of P-factor, while the kappa number of pulp is gradually increased. When the P-factor is less than 200, the solid content of the black liquor is increased from 138.48 g/L in the control group to 162.86 g/L, the lignin content is increased from 58.57 g/L to 72.68 g/L, and the residual alkalinity content is decreased from 4.37 g/L to 2.07 g/L. When the P-factor at 200—600, the solid content of black liquor is reduced from 162.86 g/L to 142.71 g/L, the lignin content is reduced from 72.41 g/L to 59.16 g/L, and the residual alkalinity content is reduced from 2.07 g/L to 1.26 g/L. When the P-factor is greater than 600, the solid content of the black liquor is increased from 142.71 g/L to 156.95 g/L, the lignin content is increased from 59.16 g/L to 62.16 g/L, and the residual alkali content is increased from 1.26 g/L to 1.37 g/L. Under different conditions, the content of inorganic substance in black liquor changed little, and the calorific value of solid substance in black liquor increased from 13.71 MJ/kg in control group to 14.63—15.09 MJ/kg.

Key words: biomass, hydrolysis, black liquor, hydrothermal, kraft pulping