| abstract |
extraction of valuable components from bark. The present invention relates to a process for extracting valuable components from a raw material rich in tannin, by carrying out an alkaline cooking step, followed by acid precipitation to separate the valuable components from the remaining skin pulp. the invention also relates to the use of said process in a side stream of bark of a chemical pulping plant, whereby the liquor remaining after extraction from the present process is returned to a stream of the wood pulping process, typically to a black liquor stream, while spent pulp can be further processed, for example, by bleaching to generate dissolved pulp. |