Editing Kraft process (section)

===Process chemicals===
Process chemicals are added to improve the production process:
* Impregnation aids. [[Surfactant]]s may be used to improve impregnation of the wood chips with the cooking liquors.
* [[Anthraquinone]] is used as a digester additive. It works as a [[redox]] [[catalyst]] by oxidizing [[cellulose]] and reducing [[lignin]]. This protects the cellulose from degradation and makes the lignin more water-soluble.<ref>{{cite book |last=Goyal|first=Gopal C. |title=Anthraquinone Pulping. A TAPPI Press Anthology of Published Papers, 1977-1996 |year=1997 |publisher=TAPPI Press |location=Atlanta |isbn=0-89852-340-0}}</ref>
* An [[flocculant|emulsion breaker]] can be added in the soap separation to speed up and improve the separation of soap from the used cooking liquors by flocculation.<ref>{{Cite web |url=http://wcm.paprican.ca/wcmpaprican/publishing.nsf/AttachmentsByTitle/BO_Tall_Oil_Soap_PDF_Eng/$FILE/0225-E-TallOilSoapRecovery.pdf |title=Tall Oil and Tall Oil Soap Recovery |access-date=2008-12-19 |archive-url=https://web.archive.org/web/20120305151739/http://wcm.paprican.ca/wcmpaprican/publishing.nsf/AttachmentsByTitle/BO_Tall_Oil_Soap_PDF_Eng/$FILE/0225-E-TallOilSoapRecovery.pdf |archive-date=2012-03-05 |url-status=dead }}</ref>
* [[Defoamer]]s remove foam and speed up the production process. Drainage of washing equipment is improved and gives cleaner pulp.
* [[Dispersing agent]]s, [[detackifier]]s and [[complexing agent]]s keep the system cleaner and reduce the need for maintenance stops.
* Fixation agents fix finely dispersed potential deposits to the fibers and thereby transport them out of the process.