红松木烧碱法制浆黑液中木质素对污染负荷影响

Effect of Lignin in Red Pine Wood Alkaline Pulping Black Liquor on Pollution Load

为研究蒸煮黑液中木质素对污染负荷影响,研究了红松木片化学浆蒸煮黑液的污染特性及特征污染物,通过紫外-可见光谱法建立了快速测定液相木质素的分析方法及木质素对COD贡献的工作曲线,探究黑液中木质素对总COD污染负荷的贡献.结果表明蒸煮过程中,黑液中含有较高浓度的溶解态有机物,可生化处理性差,成分复杂,主要有机污染物为酚类和有机酸类物质,其中酚类化合物的相对含量高达84.34%;经测定黑液中木质素浓度为65.7g·L^(-1),产生COD_(cr)值高达93 640.86mg·L^(-1),占黑液总CODcr含量的51%左右,黑液中木质素对黑液废液污染有较大的贡献.

Pollution feature and characteristic pollutants in black liquor of red pine chemical pulping were studied to reveal the contribution of lignin in black liquor to pollution load. A UV-visible spectrometry method to determine lignin content in black liquor was established, together with the work curve of the contribution of lignin to the COD content, to explore the contribution of lignin to the COD content.It was found in the cooking process that the concentration of dissolved organic compounds in the black liquor was high with poor biodegradability and complex components. The main organic pollutants include phenolic and organic acid compounds, where the phenolic compounds have up to 84.34% relative concentration. Lignin concentration in black liquor is 65.7 g·L -1 with produced CODcr value as high as 93 640.86 mg·L -1 ,which accounts for about 51% of the total CODcr load in black liquor. The results show that lignin is the main source of pollution load for black liquor in traditional chemical pulping industry.