scholarly journals Formic Acid Pulping of Bagasse

1970 ◽  
Vol 41 (3) ◽  
pp. 245-250 ◽  
Author(s):  
M Sarwar Jahan

Atmospheric formic acid pulping of bagasse was done with varying formic acid concentration and cooking time. Pulp yield and kappa number decreased with increasing formic acid concentration or cooking time. The optimal cooking conditions were 90 % formic acid and 90 min of cooking at 95°C. The pulp yield at this condition was 44.4 % and kappa number 26.1. The strength properties were acceptable in formic acid pulping of bagasse. Addition of H2SO4 catalyst in formic acid degraded carbohydrate, resulting lower pulp yield and inferior strength properties. The strength properties were improved slightly after bleaching. Bangladesh J. Sci. Ind. Res. 41(3-4), 245-250, 2006

TAPPI Journal ◽  
2015 ◽  
Vol 14 (2) ◽  
pp. 73-81 ◽  
Author(s):  
GISELY SAMISTRARO ◽  
PETER W. HART ◽  
JORGE LUIZ COLODETTE ◽  
RICARDO PAIM

Eucalyptus dunii has been commercially used in southern Brazil because of its relatively good frost tolerance and adequate productivity in the winter months. More recently, interest has grown in cultivating Eucalyptus benthamii Maiden & Cambage, which presents even superior frost tolerance compared to E. dunii and is highly productive as well. The quality of E. benthamii for pulp production is not yet proven. Thus, the chemical, anatomical, and technological aspects of pulp made from E. benthamii were compared with those of E. dunii for unbleached paper production. Samples of E. benthamii chips were obtained and analyzed for their basic density, chemical composition, higher heating value, trace elemental analysis, and chip size distribution. The chips were kraft cooked using conditions that produced a 74 ± 6 kappa number. The pulps were characterized for kappa number, yield, viscosity, and morphologic characteristics (e.g., length, wall thickness, and coarseness). Black liquor was analyzed for total solids, organics, inorganics, sodium sulfide, sodium hydroxide, and sodium carbonate. Brownstocks were beaten at five different energy levels in a Valley beater, and the physical strength properties of 120 g/m² handsheets were measured to develop a beater curve. The results of this study showed differences in delignification between the two woods and lower pulp yield for E. benthamii , which are related to their chemical compositions and basic densities. The E. benthamii studied in this work exhibited higher amounts of lignin and extractives, lower carbohydrate content, and lower basic density. However, cooking a blend of the two woods afforded good results in pulping and in physical pulp properties.


BioResources ◽  
2010 ◽  
Vol 6 (1) ◽  
pp. 103-120
Author(s):  
Harjeet Kaur ◽  
Dharm Dutt ◽  
C. H. Tyagi

Sofia (Cymbopogon martini), and lemon (Cymbopogon flexuosus) grasses, are exclusively cultivated for extraction of important lemongrass and palma rosa oils. Lignocellulosic residue (LCR) of sofia and lemon grasses left after steam distillation can successfully be used for the production of chemical grade pulp. Steam distillation mitigates the problem of mass transfer, and facilitates the faster penetration of cooking liquor by leaching out a part of extraneous components. Sofia grass produces a pulp yield of 43.7% of kappa number 20 at an active alkali dose of 14% (as Na2O), maximum cooking temperature of 160 oC and cooking time 90 min. Likewise, lemon grass produces a pulp yield of 41.4% of kappa number 12.5 under the same conditions except temperature (150 oC) by a soda pulping process. Addition of 0.1% AQ at optimum cooking conditions reduces kappa number by 26 and 8% for sofia and lemon grasses with insignificant increase in pulp yield i.e. 0.2 and 0.4% for sofia and lemon grasses, respectively. The mechanical strength properties of lemon grass soda-AQ pulp are better than sofia grass. Bauer-McNett fiber classification further validates that +20 fractions are more (62.63%) in lemon grass than in sofia grass (42.72%).


2018 ◽  
Vol 33 (2) ◽  
pp. 175-185 ◽  
Author(s):  
Gustavo B. de Souza ◽  
Jorge Luiz Colodette ◽  
Fernando José Borges Gomes ◽  
Danila Morais de Carvalho

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.


Holzforschung ◽  
2000 ◽  
Vol 54 (5) ◽  
pp. 544-552 ◽  
Author(s):  
S. Abad ◽  
V. Santos ◽  
J. C. Parajó

Summary Populus tremula* Populus tremuloides wood samples were subjected to three-stage pulping in formic acid media with hydrogen peroxide addition, according to the Milox process. By means of three incomplete, second-order, centered, factorial designs, the effects of selected operational variables on the composition and technical properties of pulps were assessed for optimization purposes. Under the best conditions assayed, a pulp with 2.30% lignin, 87.0 % cellulose and 3.25% xylan was obtained at 53.2% pulp yield. Good SCAN viscosity (826 ml/g), reduced Kappa number (9.0) and satisfactory alkaline resistance (R-10 = 89.0; R-18 = 91.0) proved the potentiality of the selected pulp for dissolving pulp production.


TAPPI Journal ◽  
2013 ◽  
Vol 12 (9) ◽  
pp. 41-46 ◽  
Author(s):  
M. SARWAR JAHAN ◽  
SUMON GOSH ◽  
M. MOSTAFIZUR RAHMAN ◽  
YONGHAO NI

Utilization of jute cutting and caddis is of social and economic importance in Bangladesh. In this study, soda-anthraquinone, alkaline sulfite-anthraquinone, and neutral sulfite-anthraquinone processes were evaluated for jute-cutting and caddis pulping. The NS-AQ process showed favorable pulp yield and kappa number for both of these raw materials: 66.1% for jute cuttings and 59.9% for caddis at kappa no. 11. The physical properties of NS-AQ pulps were also better than those of soda-AQ and AS-AQ pulps. At 0SR 44, the tensile index of NS-AQ pulp was about 100 N.m/g for jute cutting and 70 N.m/g for caddis, and the tear index was similar. All pulps were bleached by D0EpD1 bleaching sequences. The NS-AQ pulp showed excellent bleachability. Its brightness reached 89.0% for jute cuttings and 85.0% for caddis using total chlorine dioxide of about 15 kg/ton. After bleaching, the strength properties of NS-AQ pulp were slightly better compared to soda-AQ and AS-AQ pulps.


2012 ◽  
Vol 468-471 ◽  
pp. 1211-1215 ◽  
Author(s):  
Hong Li ◽  
Bing Sun ◽  
Yu Xin Liu ◽  
Ke Li Chen

In this paper, the bagasse wet-stored with hypochlorite (H) bleaching waste-water which was the original waste liquid from H bleaching process of bagasse, was cooked with alkali-oxygen and its pulping effect was studied. The results showed that the proper treatment time of wet storage with H bleaching waste-water was 12 days, the pulping properties were as follows: screened pulp yield 62.9%, kappa number 15.4, viscosity 802 mL/g, and brightness 58.8 %ISO. The strength properties of pulp were as follows: tensile index 65.6 N•m/g, tear index 5.86 mN•m2/g, burst index 3.83 kPa•m2/g and folding endurance 302 times. In addition, the pulping properties of bagasse wet-stored with H bleaching waste-water were similar to those of bagasse wet-stored with fresh water. Therefore, it can be concluded that the H bleaching waste-water could be used as spraying water for wet storage of bagasse. It was a new idea for saving fresh water in the pulping and papermaking industry.


2020 ◽  
Vol 35 (3) ◽  
pp. 325-331
Author(s):  
Sandeep Kumar Tripathi ◽  
Izhar Alam ◽  
Nishi Kant Bhardwaj

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.


BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 5361-5375
Author(s):  
Laxman Kumar Pandey ◽  
Amit Kumar ◽  
Surendra Pal Singh ◽  
Dharm Dutt

Mechanical pulping of raw wood material is a highly energy intensive and pollution generating step in the papermaking process. This study focused on combined mechanical and xylanase treatment prior to the kraft pulping of E. tereticornis. A screened pulp yield of 49.1% (on oven-dry wood basis) with a Kappa number of 24.9 was obtained at the optimum cooking temperature of 160 °C without any pretreatment of the wood chips. After mechanical treatment (destructuring), a slightly higher screened pulp yield (49.4%) was obtained with a Kappa number of 24.2 at the cooking temperature of 145 °C with the same active alkali charge (15%). The optimum cooking temperature was further reduced to 140 °C for the destructured xylanase-treated wood chips. The xylanase treatment resulted in a 2% reduction in screened pulp yield due to hydrolysis of xylan. However, the Kappa number was reduced to 18.2 after xylanase pretreatment of the mechanically destructured wood chips. The combined pretreatment (destructured and xylanase treatment) of wood chips resulted in a reduction in cooking temperature by 20°C compared to untreated wood chips. Such a reduction in cooking temperature can effectively reduce steam consumption. The combined pretreatment improved the pulp brightness by 2.0 (ISO points) and physical strength properties, which included the tensile index, tear index, and burst index by 11.06%, 21.72%, and 21.79%, respectively, compared to the control.


2016 ◽  
Vol 1 (02) ◽  
Author(s):  
Paryono ,

In this study, the unbleached pulp was made in the laboratory by cooking conditions: Active Alkali (AA) 18%, Sulfidity (S) 32%, ratio 1: 4, maximum temperature 165 oC, with cooking time of 2 + 1.5 hours. Pulp with kappa number of 20.01 and 52.30% yield was produced. Oxygen bleaching process was varied into a single stage bleaching process, a two-stage bleaching process with and without washing. The results showed that the two stages oxygen bleaching processes, without washing with variation of NaOH addition 100:0 and 80:20 gave the higher reduction of kappa number and the increasing of bleaching yield compare to one stage oxygen bleaching. The higher reduction of kappa number gave the higher of reduction of viscosity, but had no effect on fiber composition. Two oxygen stage bleaching without washing is recommended.Key words : oxygen bleaching, kappa number, viscosity, yield filtered  ABSTRAKPada penelitian ini pulp belum putih dibuat di laboratorium dengan kondisi pemasakan : AA 18 %, S 32 %, rasio 1 : 4, temperatur maksimum 165 OC, dan waktu 2 + 1,5 jam. Dihasilkan pulp dengan bilangan kappa 20,01 dan rendemen tersaring 52,30 %. Proses pemutihan oksigen divariasi menjadi proses pemutihan satu tahap, proses pemutihan dua tahap dengan dan tanpa pencucian. Hasil penelitian menunjukkan pemutihan oksigen dua tahap tanpa proses pencucian dengan variasi penambahan NaOH 100 : 0 dan 80 : 20 memberikan penurunan bilangan kappa yang lebih besar dan peningkatan rendemen pemutihan dibanding dengan pemutihan oksigen satu tahap. Penurunan viskositas sebanding dengan penurunan bilangan kappa, dimana semakin besar penurunan bilangan kappa juga mengakibatkan penurunan viskositas yang semakin besar tetapi tidak berpengaruh terhadap komposisi serat. Pemutihan oksigen dua tahap tanpa proses pencucian sangat disarankan. Kata kunci : pemutihan oksigen, bilangan kappa, viskositas, rendemen tersaring  


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