Suitability of Some wood Species from Upper Nile State For Pulp and Papermaking ( Sudan )

No Thumbnail Available
Otuk Tuphach, Selim
Journal Title
Journal ISSN
Volume Title
Upper Nile State is rich in most of the basic factors required to establish paper industry, such as availability of water and fibrous woody and nonwoody species. To assess the suitability of some wood species from the study area for pulp and paper manufacture, five wood species, namely Cordia africana, Crateva adansonii, Combretum glutinosum , Sclerocarya birrea , Terminalia brownii ,were studied . Evaluation of physicals, anatomical features, fibers morphological indices, chemical composition, soda pulping with or without anthraquinone, beating without and with gum Arabic guar gum addition were carried out. The wood species studied are different densities, woods suitable for pulping. The bark-to-wood ratio for Terminalia brownii, Cordia africana, Compbertum gautinosum, sclercarya birrea, were in normal range for pulp woods, but for crateva adansonii, the ratio was low, but acceptable. Fiber calibrations were determined by microscopical observations and by fiber classifications. The fibers studied were short (1.31 mm for Cordia africana, 0.66 mm for Crateva adansonii, 1.28 mm for Combretum glutinosum, 1.04 for Sclerocarya birrea, 1.22 mm for Terminalia brownii) . They were in the normal range of hardwoods for commercial pulping having medium thick walls (1.060 – 0.857 – 1.061 – 1.078 – 1.062 μm respectively ) thinnest for Crateva adansonii and thickest for Cordia africana, Combretum glutinsum, Sclercarya birrea, terminalia brownii. XI The chemical composition of the five wood species was somewhat different, but the differences were typically for tropical hardwoods. The good cellulose contents of five wood species predicted good yields. The overall chemical composition of the wood species indicated the suitability of the alkaline methods for pulping with reasonable alkali charge and predicted acceptable good yields. The species pulped easily with alkali charge of 12-16% as Na2O at 120 minuets cooking time at maximum temperature of 170°C to bleachable Kappa values. Addition of 0.13% anthraquinone reduced the active alkali by 2-2.3% and increased the yield of Cordia africana by 2%. Gum Arabic, guar gum (0.5% on oven dry pulp) were added during the beating of soda-AQ pulps and their effects were reflected in increased inter fiber bonding and shorten beating cycle. The gums overcame the tear reduction resulted from the addition anthraquinone in pulping. Papermaking properties of various pulps indicated suitability for products requiring strength as well as for fine papers, such as printing and writing