Around 1.3 billion tonnes of weak Kraft black liquor is produced every year, and is usually concentrated by evaporation and burned to produce energy. Nevertheless, this strategy implies that many valuable compounds of great industrial interest are destroyed. This article compiles the available information about valorising Kraft black liquor by obtaining chemical products. Although this topic is arousing interest, more research is needed, as only processes which have not yet been validated at industrial scale are described, except for lignin recovery. Due to the heterogeneity of the raw material, complex and integrated processes are being proposed to extract different existing and/or generated compounds. The most common approach is a first stage of lignin recovery by precipitation, followed by the use of the delignified black liquor to obtain principally organic acids, and/or as a fermentation medium, recirculating the by-product streams into the Kraft process to recover the inorganic salts.

每年生产约 13 亿吨弱牛皮纸黑液，通常通过蒸发浓缩并燃烧产生能量。然而，这种策略意味着许多具有重大工业价值的有价值的化合物被破坏了。本文汇编了有关通过获取化学产品来提高牛皮纸黑液价值的可用信息。虽然这个话题引起了人们的兴趣，但还需要更多的研究，因为除了木质素回收之外，只描述了尚未在工业规模上得到验证的工艺。由于原材料的异质性，人们提出了复杂和集成的工艺来提取不同的现有和/或生成的化合物。最常见的方法是通过沉淀回收木质素的第一阶段，