Chemical, anatomical and technology aspects, for Eucalyptus benthamii x Eucalyptus dunnii for use in pulp and paper mill.

摘要

The chemical, anatomical and technological aspects of pulp made from Eucalyptus benthamii was compared with Eucalyptus dunnii pulp for paper production. Samples of E. benthamii chips were obtained and analyzed for basic density, lignin (acid-soluble, acid insoluble and total), extractives, carbohydrates (glycans, xylans, galactans, mannans and arabinans), uronic acids, higher heating value and trace elemental analysis , MOE, metals content (silica , Na, K, Ca, Mn, Mg, K, CI, Na and Cu) and particle size classification . The chips were Kraft cooked using conditions that produced a 70 ± 5 kappa number. The pulps were analyzed and characterized by kappa number, yield, viscosity and fiber dimensions (length, width, lumen diameter and wall thickness of the fibers, fiber coarseness, fiber count /gram). Black liquor from the pulping process was analyzed for per cent solids, organics, inorganics, Na2S, NaOH and Na2CO3. The pulp was refined to 5 different levels in a valley beater employing 5 minute intervals between 1 and 20 minutes. For each level of refining, Canadian Standard Freeness was determined and 120 g/m2 handsheets were made. The handsheets were conditioned and tested for: Compressive strength (STFI - SCT, RCT, CMT), tear resistance (Elmendorf) and tensile strength. The severe frost resistance of E. benthamii Maiden et Cambage has created significant interest in colder regions which desire improved forest productivity. The results of this study showed differences in delignification between the two woods and showed lower pulp yield for E. benthamii; possibly associated with differences in chemical composition. The E. benthamii studied in this work exhibited higher amounts of lignin, extractives, lower carbohydrate content, lower specific gravity and shorter fiber length. The lignin, extractives and carbohydrates directly influence the alkali consumption, yield and production potential. However, cooking a blend of the two woods showed good results in both pulping and in physical and mechanical pulp properties