Sulfite Pulping of Southern Pines

Acid sulfite, bisulfate, and neutral sulfite pulping processes are reviewed with regard to their use in the pulping of southern pine, and future possibilities for improving sulfite pulping are discussed. Data on the southern pines are limited but extensive data on other conifers, with similar pulping characteristics, indicate the applicability of these processes to the southern pines. The stiff bulky fibers, characteristic of southern pines, will probably limit the commercial exploitation of sulfite processes to those whose liquors are neutral or only slightly acid. It would seem, at the present state of the art, that neutral sulfite semichemical pulps show good prospects of successful competition with kraft. It may be possible to produce pulps of 60 percent or higher yield, as strong as kraft, and considerably brighter in color. Processes are available for chemical recovery and elimination of the sulfite ion in the cooking liquor that should simplify air pollution problems. In tissue, bond, book, business papers, and the like, the southern pines, because of their harsh, stiff, fiber characteristics, cannot be used as the major component in the sheet.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member