摘要 |
The method increases the yield and improves the beatability of kraft pulp. During the progression of the cooking process, more than one cooking liquor with a dissolved content of hemicellulose is drawn off and then reintroduced to the last phases of the cooking process, to re-precipitate the hemicellulose on the fibers. The hemicellulose rich cooking liquors are adjusted so that they, upon being added to the last phase of the cooking process are optimized. Early dissolved hemicellulose has a longer chain length than the hemicellulose that dissolves in the cooking liquor in the later phases of the cooking process, and they also have different tendencies to precipitate on the wood chips softened in the cooking process.
|