| 摘要 |
<p>During the production of kraft pulp, by kraft cooking, one or more hemicellulose-rich extractions are treated to separate and remove a significant portion of the hemicellulose. This may be accomplished by treating the extraction with an oxidant, or by acidification to precipitate lignin out of the solution. Treatment may also include ultrafiltration at a temperature greater than 100 °C utilizing inorganic membranes, and reconstitution such as cross-linking to promote re-polymerization, or agglomeration to produce coagulated hemicellulose. After separation of the hemicellulose it is redeposited on the kraft pulp, for example in an E bleach stage, downstream of any oxygen or ozone stages. There is also a method of bleaching kraft pulp according to the sequence OODEDD, OODEPDD, or OOZEP, where the E stage includes a saccharide redeposition treatment. The kraft pulp product has increased yield and bonding compared to conventional kraft pulp.</p> |
