scholarly journals Comparison of two bar edge lengths of refining plates on the properties of American old corrugated container pulp during low consistency refining

BioResources ◽  
2019 ◽  
Vol 15 (1) ◽  
pp. 347-359
Author(s):  
Hui Cai ◽  
Zhaoyang Yuan ◽  
Guolin Tong ◽  
Xin Zhang ◽  
Hui Zhang
Keyword(s):  
Tensile Strength ◽  
Specific Energy ◽  
Lower Energy ◽  
Energy Input ◽  
Fibre Length ◽  
Strength Properties ◽  
Strength Development ◽  
Low Intensity ◽  
Plate Geometry ◽  
Length Reduction

Commercial American old corrugated container pulp (AOCC) boards were used as the starting material for repulping and low consistency (LC) refining to investigate the effects of LC refining plate geometry on the fibre and strength properties of the generated pulp. Specific refining energy that ranged from 0 to 120 kWh/air-dried ton (ADT) of pulp was explored for the two bar edge lengths (BEL) of refining plate patterns, wide 0.99 km/rev BEL and interim 2.01 km/rev BEL. The results showed that fibre length, curl index, kink index, and pulp freeness decreased while fines content increased with increasing refining energy input for both of the two refining plates during LC refining. LC refining with 2.01 BEL plate at low intensity of 0.24 J/m showed less fibre length reduction and more tensile strength development than that obtained with 0.99 BEL plate at high intensity of 0.48 J/m when compared at the same specific energy. Moreover, to achieve the desired tensile strength of the AOCC pulp, lower energy was needed for the interim 2.01 BEL plate than the wide 0.99 BEL plate. Thus, the interim 2.01 km/rev BEL refining plate provided potential for saving refining energy to reach a desired tensile strength of AOCC pulp.

scholarly journals MECHANICAL PULPING.Effect of long fibre concentration on low consistency refining of mechanical pulp

2012 ◽  
Vol 27 (4) ◽  
pp. 702-706 ◽  
Author(s):  
Stefan Anderssou ◽  
Christer Sandberg ◽  
Per Engstrand
Keyword(s):  
Energy Consumption ◽  
Specific Energy ◽  
Specific Energy Consumption ◽  
Fibre Length ◽  
Pilot Scale ◽  
Process Conditions ◽  
Mechanical Pulp ◽  
Fibre Concentration ◽  
Fibre Network ◽  
Length Reduction

Abstract The aim of this study was to investigate the influence of lang fibre concentration on Ioadability and pulp properties during LC refming of mechanical pulp. Lang fibre concentration was adjusted to three different Ievels by screen fractionation of the pulp. The three pulps were refined in a single disc pilot scale LC refiner at simi1ar process conditions. Increased lang fibre concentration suppmied a larger refiner gap and resulted in less fibre . cutting at a given specific energy consumption. The higher lang fibre concentration probably contributed to a stronger fibre network that maintained a !arger refining gap at certain specific energy consumption. Increased long fibre concentration also enabled a higher tensile index increase in the LC refmer at certain fibre length reduction. The study supports a process combining LC refining with screen fractionation, where the lang fibre fraction is recycled to the refiner feed. This enables a . higher Ioadability and a more effective utilisation of the LC refiner. By using this technology, overall specific energy consumption can be reduced if a !arger share of the refining is performed in LC rather than HC refining.

Tear and tensile strength development of PGW and CTMP pulps mixed with PLA or viscose fibres

2014 ◽  
Vol 29 (2) ◽  
pp. 304-308 ◽  
Author(s):  
Jaakko Asikainen ◽  
Antti Korpela
Keyword(s):  
Tensile Strength ◽  
Fibre Length ◽  
Wood Fibre ◽  
Strength Development ◽  
Paper Properties ◽  
Mechanical Pulp ◽  
Tear Strength ◽  
Tear Index ◽  
Simultaneous Decrease ◽  
A Minor

Abstract The objective was to evaluate the effects on paper properties when replacing a minor share of wood fibre by synthetic fibre. The aim was to increase tear strength and stretch while minimizing the loss of tensile strength in paper consisting of mechanical pulp. Tested synthetic fibres included PLA and viscose fibres mixed with mechanical or chemi-mechanical pulp. Even at relatively low proportions, the synthetic fibres contributed to a significant increase of tear strength in the wood fibre based papers. With the highest tested proportion (20%) the increase of tear index in PGW based stock was 243% with PLA and 177% with viscose fibre. However, a simultaneous decrease in tensile strength and tensile stiffness was observed. The stretch at break remained unchanged. Thickness reduction of the synthetic fibres resulted in an increase of tear strength. The effect is due to the high fibre length of synthetic fibres, producing mechanically well entangled networks, coupled with the high enough strength of the synthetic fibres.

The Importance of Xylan for the Strength Properties of Spruce Kraft Pulp Fibres

Holzforschung ◽  
2001 ◽  
Vol 55 (6) ◽  
pp. 639-644 ◽  
Author(s):  
C. Schönberg ◽  
T. Oksanen ◽  
A. Suurnäkki ◽  
H. Kettunen ◽  
J. Buchert
Keyword(s):  
Tensile Strength ◽  
Chemical Composition ◽  
Fracture Energy ◽  
Kraft Pulp ◽  
Fibre Length ◽  
Strength Properties ◽  
Total Charge ◽  
Pulp Fibres ◽  
Considerable Impact

Summary In this work the role of xylan in spruce kraft pulp fibres was investigated by selectively removing the pulp fibre xylan and also by sorbing xylan onto the pulp fibres. The effects of xylan removal and sorption on fibre properties were measured and the chemical composition of the fibres and also that of the selectively removed xylans was analyzed. According to the results the xylanase could act on both sorbed and native xylan located on accessible fibre surfaces. Xylan was found to affect the strength properties of handsheets. The location and the charge of xylan had a considerable impact on the formation of interfibre bonds. Scott Bond-values correlated with the amount of surface xylan on fibre surfaces, whereas tensile strength was affected by the total amount of xylan and particularly by the total charge of the fibres. The fracture energy was determined by the combined effect of interfibre bonding ability and effective fibre length.

Fibre characteristics and paper properties of formic acid / peroxyformic acid birch pulps

1997 ◽  
Vol 12 (4) ◽  
pp. 237-243 ◽  
Author(s):  
Anu Seisto ◽  
Krisriina Poppius-Levlin
Keyword(s):  
Tensile Strength ◽  
Formic Acid ◽  
Kraft Pulp ◽  
Strength Properties ◽  
Kappa Number ◽  
Strength Development ◽  
Paper Properties ◽  
Fibre Breakage ◽  
High Degree ◽  
Peroxyformic Acid

Abstract The fibre and paper properties of nine unbleached formic acid / peroxyformic acid (MILOX) pulps with kappa number 6-20 were studied and compared with a kraft pulp with kappa number 20. The degree of deformation was greater in the MILOX fibres, affecting the paper properties of the MILOX pulps. The large number of curl and kinks in the MILOX fibres were probably caused mechanically. The MILOX fibres showed greater conformability, resulting in higher paper density. The defects in the MILOX fibres were apparently so severe as to cause fibre breakage during PFI beating of the pulps. As a result of both fibre deformation and breakage, the tensile strengths of the MILOX pulps were lower than that of the reference kraft pulp, and tensile strength development during beating was slower. The tear strength of the best MILOX pulp was lower than that of the kraft pulp when compared at the same tensile index. Fibre deformation in both MILOX and the kraft pulp increased during bleaching. The kinks in the fibres were possibly set into position, giving the bleached MILOX pulps poorer bonding ability and lower paper density. A high degree of fibre defo~mation had the same effect on the tensile strength development of the bleached MILOX pulps as it did in the unbleached state. The light scattering properties of the MlLOX pulps were better than those of the kraft pulp, possibly due to the higher fines content of the MILOX pulps. The results indicate that more attention should be given to mechanical treatments during MILOX pulping in order to bring the strength properties closer to those of kraft pulp.

Increased dryness after pressing and wet web strength by utilizing foam application technology

TAPPI Journal ◽  
2016 ◽  
Vol 15 (11) ◽  
pp. 731-738 ◽  
Author(s):  
KARITA KINNUNEN-RAUDASKOSKI ◽  
KRISTIAN SALMINEN ◽  
JANI LEHMONEN ◽  
TUOMO HJELT
Keyword(s):  
Tensile Strength ◽  
Guar Gum ◽  
Paper Industry ◽  
Reference Sample ◽  
Strength Properties ◽  
Cellulose Microfibrils ◽  
Application Technology ◽  
Ethylene Vinyl Alcohol ◽  
Wet Pressing ◽  
Web Strength

Production cost savings by lowering basis weight has been a trend in papermaking. The strategy has been to decrease the amount of softwood kraft pulp and increase use of fillers and recycled fibers. These changes have a tendency to lower strength properties of both the wet and dry web. To compensate for the strength loss in the paper, a greater quantity of strength additives is often required, either dosed at the wet end or applied to the wet web by spray. In this pilot-scale study, it was shown how strength additives can be effectively applied with foam-based application technology. The technology can simultaneously increase dryness after wet pressing and enhance dry and wet web strength properties. Foam application of polyvinyl alcohol (PVA), ethylene vinyl alcohol (EVOH), carboxymethyl cellulose (CMC), guar gum, starch, and cellulose microfibrils (CMF) increased web dryness after wet pressing up to 5.2%-units compared to the reference sample. The enhanced dewatering with starch, guar gum, and CMF was detected with a bulk increase. Additionally, a significant increase in z-directional tensile strength of dry web and and in-plane tensile strength properties of wet web was obtained. Based on the results, foam application technology can be a very useful technology for several applications in the paper industry.

scholarly journals Evaluation of the Impact of Organic Fillers on Selected Properties of Organosilicon Polymer

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1103
Author(s):  
Sara Sarraj ◽  
Małgorzata Szymiczek ◽  
Tomasz Machoczek ◽  
Maciej Mrówka
Keyword(s):  
Tensile Strength ◽  
Natural Fiber ◽  
Accelerated Aging ◽  
Strength Properties ◽  
Visual Observation ◽  
Walnut Shell ◽  
Pistachio Shell ◽  
Thermoplastic Matrix ◽  
Static Tensile ◽  
The Impact

Eco-friendly composites are proposed to substitute commonly available polymers. Currently, wood–plastic composites and natural fiber-reinforced composites are gaining growing recognition in the industry, being mostly on the thermoplastic matrix. However, little data are available about the possibility of producing biocomposites on a silicone matrix. This study focused on assessing selected organic fillers’ impact (ground coffee waste (GCW), walnut shell (WS), brewers’ spent grains (BSG), pistachio shell (PS), and chestnut (CH)) on the physicochemical and mechanical properties of silicone-based materials. Density, hardness, rebound resilience, and static tensile strength of the obtained composites were tested, as well as the effect of accelerated aging under artificial seawater conditions. The results revealed changes in the material’s properties (minimal density changes, hardness variation, overall decreasing resilience, and decreased tensile strength properties). The aging test revealed certain bioactivities of the obtained composites. The degree of material degradation was assessed on the basis of the strength characteristics and visual observation. The investigation carried out indicated the impact of the filler’s type, chemical composition, and grain size on the obtained materials’ properties and shed light on the possibility of acquiring ecological silicone-based materials.

scholarly journals Absorption and Strength Properties of Short Carbon Fiber Reinforced Mortar Composite

Buildings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 300
Author(s):  
Md. Safiuddin ◽  
George Abdel-Sayed ◽  
Nataliya Hearn
Keyword(s):  
Tensile Strength ◽  
Carbon Fiber ◽  
Water Absorption ◽  
Carbon Fibers ◽  
Strength Properties ◽  
Fiber Content ◽  
Test Results ◽  
Air Content ◽  
Entrapped Air ◽  
Short Carbon

This paper presents the water absorption and strength properties of short carbon fiber reinforced mortar (CFRM) composite. Four CFRM composites with 1%, 2%, 3%, and 4% short pitch-based carbon fibers were produced in this study. Normal Portland cement mortar (NCPM) was also prepared for use as the control mortar. The freshly mixed mortar composites were tested for workability, wet density, and entrapped air content. In addition, the hardened mortar composites were examined for compressive strength, splitting tensile strength, flexural strength, and water absorption at the ages of 7 and 28 days. The effects of different carbon fiber contents on the tested properties were observed. Test results showed that the incorporation of carbon fibers decreased the workability and wet density, but increased the entrapped air content in mortar composite. Most interestingly, the compressive strength of CFRM composite increased up to 3% carbon fiber content and then it declined significantly for 4% fiber content, depending on the workability and compaction of the mortar. In contrast, the splitting tensile strength and flexural strength of the CFRM composite increased for all fiber contents due to the greater cracking resistance and improved bond strength of the carbon fibers in the mortar. The presence of short pitch-based carbon fibers significantly strengthened the mortar by bridging the microcracks, resisting the propagation of these minute cracks, and impeding the growth of macrocracks. Furthermore, the water absorption of CFRM composite decreased up to 3% carbon fiber content and then it increased substantially for 4% fiber content, depending on the entrapped air content of the mortar. The overall test results suggest that the mortar with 3% carbon fibers is the optimum CFRM composite based on the tested properties.

scholarly journals Influence of Alumina Nanofibers Sintered by the Spark Plasma Method on Nickel Mechanical Properties

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 548 ◽  
Author(s):  
Leonid Agureev ◽  
Valeriy Kostikov ◽  
Zhanna Eremeeva ◽  
Svetlana Savushkina ◽  
Boris Ivanov ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Strength Properties ◽  
Alumina Nanoparticles ◽  
Metal Powders ◽  
Wide Range ◽  
The Matrix ◽  
Spark Plasma ◽  
Average Size

The article presents the study of alumina nanoparticles’ (nanofibers) concentration effect on the strength properties of pure nickel. The samples were obtained by spark plasma sintering of previously mechanically activated metal powders. The dependence of the grain size and the relative density of compacts on the number of nanofibers was investigated. It was found that with an increase in the concentration of nanofibers, the average size of the matrix particles decreased. The effects of the nanoparticle concentration (0.01–0.1 wt.%) on the elastic modulus and tensile strength were determined for materials at 25 °C, 400 °C, and 750 °C. It was shown that with an increase in the concentration of nanofibers, a 10–40% increase in the elastic modulus and ultimate tensile strength occurred. A comparison of the mechanical properties of nickel in a wide range of temperatures, obtained in this work with materials made by various technologies, is carried out. A description of nanofibers’ mechanisms of influence on the structure and mechanical properties of nickel is given. The possible impact of impurity phases on the properties of nickel is estimated. The tendency of changes in the mechanical properties of nickel, depending on the concentration of nanofibers, is shown.

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