麦草硫酸盐浆黑液中木素的酸化沉降与黑液性质的关系

The Relations between the Black Liquor Propertiesand the Lignin Acidifying Precipitation in Kraft WheatStraw Black Liquor

本文研究了在酸化麦草硫酸盐浆黑液沉降木素的过程中,清液和沉渣的性能和组成(体系粘度、酸化效率;沉渣体积、含水率,灰分以及有机物和无机物之比0/1;清液总固形物和CODcr)的变化与木素浓度的关系。结果表明,无论是清液还是沉渣的性能和组成都和黑液中木素的沉降有密切的关联;提取木素的比较合适的酸化终点约为pH3.0,此时CODcr的去除率为50％。

This paper has discussed the relations between the lignin content in black liquor and the changes of the property and component in the supernatuant and precipitate (the system viscosity, the acidifying efficiency, the precipitate volume, the precipitate ash content, the ratio of organic to inorganic materials of precipitate, the total solid cotent and CODcr of the supernatuant). It is shown that there are very close relations between them, and the optimum acidifying end point is about pH 3.0 for extracting lignin from black liquor, where the CODcr is decreased by 50%.