Effect of reduced pulp xylan content on wet end chemistry and paper properties — a pilot scale study

TAPPI Journal ◽  
2014 ◽  
Vol 13 (2) ◽  
pp. 29-37 ◽  
Author(s):  
KATJA LYYTIKÄINEN ◽  
ESA SAUKKONEN ◽  
MARKKU VÄISÄNEN ◽  
JUSSI TIMONEN ◽  
KAJ BACKFOLK
Keyword(s):  
Kraft Pulp ◽  
Scale Up ◽  
Pilot Scale ◽  
Partial Replacement ◽  
Paper Machine ◽  
Charge Balance ◽  
Paper Properties ◽  
Birch Kraft Pulp ◽  
Positive Effect ◽  
Xylan Content

In this scale-up study, we examined the effects of using varying amounts of fibers with reduced xylan content in paper. Bleached birch kraft pulp was partially or fully replaced by alkali-extracted pulp, and the effects of this replacement on the wet end chemistry of the paper machine and the resulting paper properties were determined. Our results show that paper properties can be maintained or improved when optimizing the partial replacement of bleached birch kraft pulp with alkali-extracted pulp. The incorporation of alkali-extracted pulp in paper machine stock had a positive effect on first pass retention and retention of chemicals. However, careful optimization of chemical dosages is required because of the altered charge balance in the wet end.

Alkaline xylan extraction of bleached kraft pulp - effect of extraction time on pulp chemical composition and physical properties

TAPPI Journal ◽  
2012 ◽  
Vol 11 (4) ◽  
pp. 37-43 ◽  
Author(s):  
ESA SAUKKONEN ◽  
KATJA LYYTIKÄINEN ◽  
KAJ BACKFOLK
Keyword(s):  
Kraft Pulp ◽  
Pilot Trial ◽  
Mechanical Damage ◽  
Pilot Scale ◽  
Extraction Time ◽  
Similar Amount ◽  
Alkaline Extraction ◽  
Paper Properties ◽  
Bleached Kraft Pulp ◽  
Birch Kraft Pulp

In this pilot scale study, we examined the effects of alkaline extraction time on xylan removal, pulp and paper properties, and the consequences that need to be addressed when scaling up and intensifying the process. Alkaline extraction of bleached birch kraft pulp yields two fractions: pure polymeric xylan and pulp with reduced xylan content. Our results indicate that a similar amount of xylan can be extracted in 5 min as the amount obtained in 60 min. We found, however, that the shorter extraction time is beneficial to maintain the fiber and paper properties at an acceptable level. This pilot trial demonstrated that the washing procedure of the alkali-treated fibers must be selected with care to avoid causing mechanical damage to fibers and to avoid the loss of fines.

scholarly journals A comparative study of enzymatic and Fenton pretreatment applied to a birch kraft pulp used for MFC production in a pilot scale high-pressure homogenizer

TAPPI Journal ◽  
2016 ◽  
Vol 15 (6) ◽  
pp. 375-381
Author(s):  
PIA HELLSTROM ◽  
ANETTE HEIJNESSON-HULTEN ◽  
MAGNUS PAULSSON ◽  
HELENA HAKANSSON ◽  
ULF GERMGARD
Keyword(s):  
High Pressure ◽  
Kraft Pulp ◽  
Pilot Scale ◽  
Enzymatic Method ◽  
Size Fractionation ◽  
Homogenization Treatment ◽  
Betula Verrucosa ◽  
High Pressure Homogenizer ◽  
Birch Kraft Pulp ◽  
Number Of Passes

Microfibrillated cellulose (MFC) was produced in pilot scale from a bleached birch (Betula verrucosa) kraft pulp that was pretreated with either Fenton’s reagent or with a combined mechanical and enzymatic method used at the Centre Technique du Papier (CTP; Grenoble, France). The change in fiber fibrillation during the homogenization treatment was monitored by analyzing the fiber and the fines content, size fractionation, rheological properties and visualization by light- and scanning electron microscopy (SEM). The Fenton pretreatment resulted in MFC suspensions that contained a high amount of small sized elements. After five passes through the highpressure homogenizer, the amount of particles smaller than 20 μm was 37% for the Fenton pretreated MFC compared to 13% for the enzymatically (endoglucanase) pretreated MFC. Altogether, the Fenton pretreatment enabled preparation of MFC with a higher degree of fibrillation after the same number of passes through the high-pressure homogenizer. Another option is to produce MFC of the same amount of fibrillation as after an enzymatic stage, but at significantly lower energy consumption.

scholarly journals Small Pilot System for the Manufacture of in Situ Precipitated Calcium Carbonate in the Presence of Pulp Fibers

2021 ◽  
pp. 118-123
Author(s):  
Klaus Dölle ◽  
Bardhyl Bajrami
Keyword(s):  
Calcium Carbonate ◽  
Calcium Hydroxide ◽  
Pilot Scale ◽  
Production Costs ◽  
Pulp Fiber ◽  
Paper Machine ◽  
Precipitated Calcium Carbonate ◽  
Paper Properties ◽  
Eucalyptus Pulp

Paper fillers materials are less expensive than fiber, allowing reduced production costs and improvement of paper properties. A small pilot scale in-situ laboratory calcium carbonate filler precipitation unit was developed and designed with the objective to provide enough pulp fiber containing in-situ precipitated calcium carbonate for a small 12-inch (304 mm) wide laboratory paper machine. The in-situ precipitation system requires the reactants calcium hydroxide and carbon dioxide and was tested with a eucalyptus pulp fiber pulp suspension. The final precipitated in-situ filler content achieved was 38.2%, 55.5% and 66.6% based on initial eucalyptus pulp fiber content. The precipitation time from an initial pH of 12.77, 12.76 and 11.98 to an final pH of 7.29, 7.55, and 7.28 for the 3 kg, 6kg, and 9 kg of calcium hydroxide reactant addition was 45 minutes for the 3 kg and 9 kg calcium hydroxide addition and 40 min. for the 6 kg calcium hydroxide addition.

Controlled retention and drainage of microfibrillated cellulose in continuous paper production

2020 ◽  
Vol 44 (32) ◽  
pp. 13796-13806 ◽  
Author(s):  
Zoheb Karim ◽  
Anna Svedberg
Keyword(s):  
Scale Up ◽  
Pilot Scale ◽  
Microfibrillated Cellulose ◽  
Paper Machine ◽  
Continuous Mode ◽  
Paper Production ◽  
Retention And Drainage

In the current study, an attempt has been made to scale up microfibrillated cellulose (MFC) reinforced paper using a pilot scale experimental paper machine (XPM) in continuous mode.

Comparison of pulp species in IONCELL-P: selective hemicellulose extraction method with ionic liquids

Holzforschung ◽  
2016 ◽  
Vol 70 (4) ◽  
pp. 291-296 ◽  
Author(s):  
Annariikka Roselli ◽  
Sari Asikainen ◽  
Agnes Stepan ◽  
Alireza Monshizadeh ◽  
Niklas von Weymarn ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Kraft Pulp ◽  
Polymer Degradation ◽  
Solvent System ◽  
Fiber Structure ◽  
Yield Losses ◽  
Optimum Conditions ◽  
Pulp Viscosity ◽  
Birch Kraft Pulp ◽  
Xylan Content

Abstract In our recent studies, it was demonstrated that the IONCELL-P process selectively dissolves hemicelluloses from bleached birch kraft pulp in a mixture of 1-ethyl-3-methylimidazolium acetate ([emim][OAc]) and water as a solvent system. The IONCELL-P method refines paper-grade pulp to dissolving pulp with <5% hemicelluloses and allows isolation of polymeric xylan without yield losses or polymer degradation. This paper is a comparative study where paper-grade pine, birch, and eucalyptus pulps are subjected to the IONCELL-P process with two [emim]-based ionic liquids (ILs), i.e. [emim]acetate and [emim]dimethylphosphate. Also, the effect of an endoglucanase pretreatment was investigated to check whether 1) the pulp viscosity could be adjusted for the following process steps before the hemicellulose extraction and 2) the decreasing pulp viscosity would open the fiber structure and thus enhance the extraction. Under optimum conditions, the birch xylan content could be reduced from 25.4% down to 1.3% and for eucalyptus from 16.6% to 2.4%. Pine pulp xylan and glucomannan were decreased from 8.1% and 7.1% to 0.9% and 2.2%, respectively. The residual hemicellulose contents of the pine pulp could be further decreased with a hemicellulase pretreatment. The selectivity of the dissolution towards hemicelluloses was better for hardwoods. Adjusting the pulp viscosity by endoglucanase prior to the IONCELL-P process reduced the selectivity as short-chain cellulose molecules were extracted along with the hemicelluloses.

scholarly journals Art Paper for Large Wood Relief Block Printing – A Paper Development Study

2021 ◽  
pp. 1-18
Author(s):  
Klaus Dölle ◽  
Hélène Rainville
Keyword(s):  
Kraft Pulp ◽  
Process Development ◽  
Paper Machine ◽  
Large Wood ◽  
Machine Direction ◽  
Paper Properties ◽  
Softwood Kraft Pulp ◽  
Bottom Side ◽  
Egg Shell ◽  
Paper Product

Wood relief block printing was developed in China in the seventh century and is used today for many art printing applications. The presented research project describes the development of an art paper product applicable for large wood relief block printing from laboratory scale to large semi commercial production of art paper for printing image sizes of up to 44-inch (1118 mm) by 96-inch (2400 mm) at outdoor steam roller printing events or smaller indoor printing press applications. The improvement of the paper properties from laboratory development, small laboratory paper machine and semi commercial paper machine run for the production of the final art paper showed an improvement throughout the process development for the optical and mechanical paper properties and exceeded the set values set by the artist using the art paper. The produced art paper with a basis weight of 260 g/m² and a thickness of 171 µm is produced from a mixture of 70% northern bleached hardwood Kraft pulp and 30% northern bleached softwood Kraft pulp. The ISO brightness of the art paper off-white (egg-shell) colour was at 63.2% and the ISO color value for L, a, b. at 90.8, 1.1, and 12.6 respectively. The art papers surface roughness and porosity as a parameter for ink attachment and penetration is for the top side 2179 ml/min and for the bottom side (wire side) 2326 ml/min, whereas porosity was measured at 1668 ml/min. Bending stiffness in machine direction and cross machine direction was measured at 157mN and 70 mN respectively. Burst strength was measured at 2.24 kPA·m²/g.

scholarly journals Pilot-Scale Production of Chito-Oligosaccharides Using an Innovative Recombinant Chitosanase Preparation Approach

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 290
Author(s):  
Chih-Yu Cheng ◽  
Chia-Huang Tsai ◽  
Pei-Jyun Liou ◽  
Chi-Hang Wang
Keyword(s):  
Cell Density ◽  
Scale Up ◽  
Cost Effective ◽  
Pilot Scale ◽  
Ionic Concentration ◽  
Dihydrogen Phosphate ◽  
Scale Production ◽  
Sodium Dihydrogen Phosphate ◽  
Selective Precipitation ◽  
Pilot Scale Production

For pilot-scale production of chito-oligosaccharides, it must be cost-effective to prepare designable recombinant chitosanase. Herein, an efficient method for preparing recombinant Bacillus chitosanase from Escherichia coli by elimination of undesirable substances as a precipitate is proposed. After an optimized culture with IPTG (Isopropyl β-d-1-thiogalactopyranoside) induction, the harvested cells were resuspended, disrupted by sonication, divided by selective precipitation, and stored using the same solution conditions. Several factors involved in these procedures, including ion types, ionic concentration, pH, and bacterial cell density, were examined. The optimal conditions were inferred to be pH = 4.5, 300 mM sodium dihydrogen phosphate, and cell density below 1011 cells/mL. Finally, recombinant chitosanase was purified to >70% homogeneity with an activity recovery and enzyme yield of 90% and 106 mg/L, respectively. When 10 L of 5% chitosan was hydrolyzed with 2500 units of chitosanase at ambient temperature for 72 h, hydrolyzed products having molar masses of 833 ± 222 g/mol with multiple degrees of polymerization (chito-dimer to tetramer) were obtained. This work provided an economical and eco-friendly preparation of recombinant chitosanase to scale up the hydrolysis of chitosan towards tailored oligosaccharides in the near future.

scholarly journals Cellulose Nanofibril (CNF) Films and Xylan from Hot Water Extracted Birch Kraft Pulps

2019 ◽  
Vol 9 (16) ◽  
pp. 3436 ◽  
Author(s):  
Marc Borrega ◽  
Hannes Orelma
Keyword(s):  
Food Packaging ◽  
Kraft Pulp ◽  
Barrier Properties ◽  
Hot Water ◽  
Kraft Pulps ◽  
Cellulose Nanofibril ◽  
Vapour Permeability ◽  
Transparent Films ◽  
Cnf Films ◽  
Birch Kraft Pulp

The effects of xylan extraction from birch kraft pulp on the manufacture and properties of cellulose nanofibril (CNF) films were here investigated. Hot water extractions of bleached and unbleached kraft pulps were performed in a flow-through system to remove and recover the xylan. After the extraction, the pulps were oxidized with 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) and fibrillated in a high-pressure microfluidizer. Compared to CNF from bleached kraft pulp, the CNF dispersions obtained from water-extracted pulps were less viscous and generally contained a higher amount of microfiber fragments, although smaller in size. In all cases, however, smooth and highly transparent films were produced from the CNF dispersions after the addition of sorbitol as plasticizer. The CNF films made from water-extracted pulps showed a lower tensile strength and ductility, probably due to their lower xylan content, but the stiffness was only reduced by the presence of lignin. Interestingly, the CNF films from water-extracted bleached pulps were less hydrophilic, and their water vapour permeability was reduced up to 25%. Therefore, hot water extraction of bleached birch kraft pulp could be used to produce CNF films with improved barrier properties for food packaging, while obtaining a high-purity xylan stream for other high-value applications.

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