Evaluation of beetle-killed white spruce for pulp and paper

1983 ◽  
Vol 13 (2) ◽  
pp. 246-250 ◽  
Author(s):  
Richard A. Werner ◽  
Erwin E. Elert ◽  
Edward H. Holsten
Keyword(s):  
White Spruce ◽  
Strength Properties ◽  
Kraft Pulping ◽  
Pulp Yield ◽  
Kraft Pulps ◽  
High Quality ◽  
South Central ◽  
Dead Trees ◽  
Standing Trees ◽  
First Results

A kraft pulping study on standing white spruce (Piceaglauca (Moench) Voss) killed by spruce beetles (Dendroetonusrufipennis (Kirby)) in south central Alaska showed no difference in pulp yield between trees dead for 1 year and those dead for as long as 50 years. Strength properties of beetle-killed white spruce remained extremely high in all dead trees regardless of how long they had been dead, so they apparently could be used for producing high-quality kraft pulps. These are the first results reported in which standing trees dead for as long as 50 years produced high-quality bleached and unbleached pulps.

scholarly journals Chemical characteristics and Kraft pulping of tension wood from Eucalyptus globulus labill

2012 ◽  
Vol 36 (6) ◽  
pp. 1163-1172 ◽  
Author(s):  
María Graciela Aguayo ◽  
Regis Teixeira Mendonça ◽  
Paulina Martínez ◽  
Jaime Rodríguez ◽  
Miguel Pereira
Keyword(s):  
Eucalyptus Globulus ◽  
Lignin Content ◽  
Strength Properties ◽  
Kraft Pulping ◽  
Pulp Yield ◽  
Chemical Characteristics ◽  
Kraft Pulps ◽  
Opposite Wood ◽  
Alkali Consumption ◽  
Pulp Strength

Tension (TW) and opposite wood (OW) of Eucalyptus globulus trees were analyzed for its chemical characteristics and Kraft pulp production. Lignin content was 16% lower and contained 32% more syringyl units in TW than in OW. The increase in syringyl units favoured the formation of β-O-4 bonds that was also higher in TW than in OW (84% vs. 64%, respectively). The effect of these wood features was evaluated in the production of Kraft pulps from both types of wood. At kappa number 16, Kraft pulps obtained from TW demanded less active alkali in delignification and presented slightly higher or similar pulp yield than pulps made with OW. Fiber length, coarseness and intrinsic viscosity were also higher in tension than in opposite pulps. When pulps where refined to 30°SR, TW pulps needed 18% more revolutions in the PFI mill to achieve the same beating degree than OW pulps. Strength properties (tensile, tear and burst indexes) were slightly higher or similar in tension as compared with opposite wood pulps. After an OD0(EO)D1 bleaching sequence, both pulps achieved up to 89% ISO brightness. Bleached pulps from TW presented higher viscosity and low amount of hexenuronic acids than pulps from OW. Results showed that TW presented high xylans and low lignin content that caused a decrease in alkali consumption, increase pulp strength properties and similar bleaching performance as compared with pulps from OW.

Kraft pulping of white spruce bole and branch

1982 ◽  
Vol 12 (2) ◽  
pp. 299-303
Author(s):  
K. N. Law ◽  
Z. Koran
Keyword(s):  
Tensile Strength ◽  
White Spruce ◽  
Kraft Pulping ◽  
Pulp Yield ◽  
Tear Strength ◽  
Branch Wood

When pulped by the same schedule, barked white spruce (Piceaglauca (Moench.) Voss.) branch wood was comparable in pulp yield to the bole wood. Handsheet made of unbeaten branch pulp showed higher bulk and stretch, comparable tensile and burst strengths, and considerably lower tear strength than bole wood. In the case of beaten pulps, branch pulp gave comparable tensile strength and stretch and lower burst and tear strengths. Inclusion of bark in the cooking increased chemical consumption and degraded sheet cleanliness. Pulping of mixtures containing up to 20% branch wood reduced the tear, burst, and tensile strengths by about 10%). It appeared that the inclusion of branch wood in the furnish within the natural amount limit in kraft pulping would be feasible.

Chemithermomechanical and kraft pulping of Pinus radiata wood chips after the hydrothermal extraction of hemicelluloses

Holzforschung ◽  
2015 ◽  
Vol 69 (1) ◽  
pp. 33-40 ◽  
Author(s):  
Pablo Reyes ◽  
André Ferraz ◽  
Miguel Pereira ◽  
Jaime Rodríguez ◽  
Regis Teixeira Mendonça
Keyword(s):  
Pinus Radiata ◽  
Energy Savings ◽  
Kraft Pulping ◽  
Wood Chips ◽  
Pulp Yield ◽  
Kraft Pulps ◽  
Pressurized Water ◽  
Pulp Viscosity ◽  
Hemicellulose Removal ◽  
Hydrothermal Extraction

Abstract Pinus radiata D. Don wood chips were submitted to a hydrothermal (HT) process, which is a pretreatment with pressurized water at P-factors of 20 (E1) and 1200 (E2), leading to 27% and 56% of hemicellulose removal, respectively. The residual wood chips were pulped by the chemithermomechanical (CTMP) and kraft processes. The pulp yield in the HT/CTMP process was in the range of 56–75%. The cellulose yields were not affected by the HT pretreatment, whereas the solubilization of hemicelluloses and lignin was intensified. The HT process provided energy savings in the refining of CTMP pulps, and the E1/CTMP pulp had a similar tensile and increased tear strength as the control wood. For kraft pulping, the HT wood chips demanded more active alkali (AA) to achieve a κ number (KN) of 30, and consequently, a decrease in pulp yield was observed (47.2% yield in the control and 44.4% and 37.8% in the E1 and E2 pulps, respectively). The fiber length decreased in the E1 and E2 kraft pulps compared with their control samples. In the E1 pulps, the tensile, tear, and burst indexes decreased by 10%, 25%, and 30%, respectively. Considering the low hemicellulose content and pulp viscosity in the range of 800–900 ml g-1, the mild HT process of P. radiata would be better suited for preparing cellulose-rich materials instead of paper-grade pulps under the biorefinery concept.

Enhancement of eucalypt pulp yield through extended impregnation cooking

2018 ◽  
Vol 33 (2) ◽  
pp. 175-185 ◽  
Author(s):  
Gustavo B. de Souza ◽  
Jorge Luiz Colodette ◽  
Fernando José Borges Gomes ◽  
Danila Morais de Carvalho
Keyword(s):  
Chlorine Dioxide ◽  
Kraft Pulp ◽  
Strength Properties ◽  
Kraft Pulping ◽  
Kappa Number ◽  
Pulp Yield

AbstractThe improvement caused by eucalypt chip impregnation on kraft pulping performance was assessed for terminating the cook at kappa in the range of 15–27 and at controlled residual effective alkali (REA) of 6–8 g/L NaOH. Extended impregnation cooking of eucalypt chips (EIC) increased about 1 %lignin- and HexA-freescreen yield gains in relation to conventional cooking (CC), regardless of kappa number in the range of 15–27. The EIC technology allows for cooking eucalypt wood to kappa number up to 27, without rejects production, but without significant improvement inlignin- and HexA-freescreen yield and with larger chlorine dioxide (ClO2) consume during bleaching. The optimum kappa number for both CC and EIC cooking was about 19 with similar refinability and strength properties for both technologies, CC and EIC. It was concluded that extended impregnation cooking is an attractive technique for enhancing bleached eucalypt Kraft pulp yield.

Modeling kraft cooking kinetics of fiber mixes from TMP and unbleached kraft pulps for assessment of old corrugated cardboard delignification

Holzforschung ◽  
2018 ◽  
Vol 72 (8) ◽  
pp. 621-629
Author(s):  
Lucas Dollié ◽  
Gérard Mortha ◽  
Nathalie Marlin
Keyword(s):  
Kraft Pulp ◽  
Kraft Pulping ◽  
Thermomechanical Pulp ◽  
Kraft Pulps ◽  
Characteristic Parameters ◽  
High Quality ◽  
Lignocellulosic Substrates ◽  
Kraft Cooking ◽  
Corrugated Cardboard ◽  
Kinetics Of

AbstractKraft cooking kinetics of three different lignocellulosic substrates have been investigated, namely fibers from unbleached kraft pulp (UBKP from Pinus radiata), fibers from softwood unbleached thermomechanical pulp (TMP), and wood chips for TMP production. UBKP and TMP were considered to be representative of a fiber mixture obtained after the pulping and cleaning of old corrugated cardboards (OCC). The characteristic parameters for fitting a mathematical model for kraft pulping were estimated. Based on the results, a “fiber mixture cooking model” was developed to predict the cooking kinetics of TMP/UBKP mixes, accounting for the proportion of each component. The aim was to tailor OCC upcycling in terms of high quality products, which can be used for various purposes including paper and non-paper applications.

Kraft pulping of jack pine killed by the Swaine sawfly

1979 ◽  
Vol 9 (2) ◽  
pp. 149-153
Author(s):  
K. Hunt ◽  
P. Benoit
Keyword(s):  
Chip Thickness ◽  
Jack Pine ◽  
Kraft Pulping ◽  
Pulp Yield ◽  
Time Since Death ◽  
Pine Sawfly ◽  
Dead Trees ◽  
Sufficient Variation ◽  
Pulp Strength

Kraft pulping studies were done on jack pine (Pinusbanksiana Lamb.) defoliated by Swaine jack pine sawfly (Neodiprionswainei Midd.). Trees dead as long as 7 years, dead and living trees sprayed with Lindane insecticide, and dead trees wrapped in cotton to prevent secondary insect attacks were tested. There was a statistically significant decrease in unscreened pulp yield (adjusted to screened pulp permanganate No. 20) with length of time since death, e.g., 44.6% (1 year) to 43.4% (7 years); but sufficient variation exists between the trees in any category such that, from a practical viewpoint, all trees tested could be used for pulp manufacture. There were no apparent differences in pulp yield between treated and untreated trees dead for the same length of time. Pulp strength decreased approximately linearly with length of time since death. A decrease in the chip thickness range of −6 mm to +2 mm (total laboratory accepts) and an increase in the −2 mm (pan) thickness range with length of time since death were observed.

Near-neutral pre-extraction of hemicelluloses and subsequent kraft pulping of southern mixed hardwoods

TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 7-15 ◽  
Author(s):  
SUNG-HOON YOON ◽  
MEHMET SEFIK TUNC ◽  
ADRIAAN VAN HEININGEN
Keyword(s):  
Dry Weight ◽  
Kraft Pulping ◽  
Weight Basis ◽  
Alkaline Solutions ◽  
Pulp Yield ◽  
Kraft Pulps ◽  
Alkaline Ph ◽  
Green Liquor ◽  
Kraft Cooking ◽  
High Alkali

Southern mixed hardwood chips were extracted with alkaline solutions at different chemical charges, times (45-110 min), and temperatures (125°C-160°C). At high alkali charges (10% and 20% sodium hydroxide [NaOH] as sodium oxide [Na2O]), the extract was strongly alkaline (pH about 13) and 17%-40% of the wood was dissolved. Subsequent kraft cooking of the extracted chips yielded 5%-7% less pulp than that of control kraft pulps. However, at reduced alkali charge, just sufficient to approximately neutralize the acids released during pre-extraction, the pulp yield (on original wood) after subsequent kraft pulping was not affected. In this case, about 5%-10% of the wood substance is removed during pre-extraction with 3% NaOH or 3% green liquor (+0.05% anthraquinone) at 140°C and 160°C for 60, 90, and 110 min. The green liquor extract obtained after 110 min at 160°C contained 2.1% (oven-dry weight basis) of sugars, 2.1% acetic acid, and 1.6% lignin accounting for 64% of the wood weight loss. Kraft pulping of the pre-extracted wood chips performed at 12% effective alkali charge showed significantly improved delignification rates and approximately the same or slightly higher yield than the kraft control at 15% effective alkali. The near-neutral green liquor+anthraquinone pre-extraction kraft pulps showed lower refining response but higher tear resistance and similar tensile strength compared to control kraft pulps.

scholarly journals Properties of bleached pulp sheets of avocado wood (Persea americana Mill.) pulped by Kraft and Soda processes

2016 ◽  
Vol 12 (1) ◽  
pp. 29-36
Author(s):  
R. Vargas ◽  
J. R. Sanjuán D. ◽  
J. A. Silva G. ◽  
J. Rivera P. ◽  
F. J. Fuentes T. ◽  
...  
Keyword(s):  
Strength Properties ◽  
Kraft Pulping ◽  
Persea Americana ◽  
Raw Material ◽  
Kraft Pulps ◽  
Reaction Conditions ◽  
Elemental Chlorine ◽  
Chemical Pulping ◽  
Pulp Strength ◽  
Soda Pulp

Chips of avocado wood (Persea americana Mill.) were pulped by means of conventional Soda and Kraft pulping processes. The pulps were bleached with an elemental-chlorine-free sequence OD1-Eop-D2, pre-setting reaction conditions for the first chlorine dioxide stage (D1) . The results show that during the chemical pulping process, avocado wood is easier to cook than other hardwoods such as eucalyptus. The avocado pulp also showed a very good bleachability, reaching brightness levels of up to 92% ISO compared to 84% for eucalyptus after the ECF bleaching sequence. The avocado Kraft pulps required more chemical input in the bleaching sequence than the Soda pulps. On the other hand, the physico-mechanical properties of the pulp were not notably reduced by the bleaching process, the Kraft pulp being stronger than the soda pulp. Strength properties of avocado are similar to those of eucalyptus; therefore this raw material constitutes a worthwhile choice for cellulosic fiber supply.

Effect of bark content in mixed hardwood chips on pulp and papermaking properties

2020 ◽  
Vol 35 (3) ◽  
pp. 325-331
Author(s):  
Sandeep Kumar Tripathi ◽  
Izhar Alam ◽  
Nishi Kant Bhardwaj
Keyword(s):  
Strength Properties ◽  
Ash Content ◽  
Kraft Pulping ◽  
Kappa Number ◽  
Raw Material ◽  
Pulp Yield ◽  
Physical Strength ◽  
Alkali Consumption ◽  
Unbleached Pulp

AbstractEffect of different proportions of bark in mixed hardwood (about 70 % eucalyptus and 30 % poplar) chips on pulp and papermaking properties was studied. Increased proportion of bark in raw material chips resulted in increased active alkali consumption, increased reject content in pulp and reduced pulp yield after kraft pulping. The unbleached pulp obtained with higher proportion of bark in mixed hardwood chips also has higher kappa number, lower brightness and viscosity as compared to pulp obtained with bark free mixed hardwood chips. The soda loss and ash content in pulp were severely increased from 12.8 kg/t to 312 kg/t of pulp and 0.7 % to 21.1 %, respectively with the increase of bark portion from 0 to 100 % in raw material furnish. The physical strength properties like tensile, burst and tear indices in the pulp obtained from bark were reduced by 58.5 %, 60.7 % and 68.4 %, respectively as compared to that with bark free mixed hardwood.

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