Showing papers in "Appita Journal in 2004"

On the design of polymers for increased paper dry strength: A review

Abstract: Water-borne polymers are routinely added the papermaking process to increase the mechanical strength of dry paper. Reviewed are the relationships between the chemical structures of the dry strength polymers and their influence on paper strength. The degree of cationic charge, the molecular weight and the presence of reactive groups on the polymer do not directly influence dry paper strength. Polymer hydrophobicity/hydrophilicity seems to be a predictor of efficacy - the more hydrophilic, the stronger the paper.

An Alternative Solution to the Silica Problem in Wheat Straw Pulping

Abstract: As a preliminary study, wheat straw pulps were prepared by soda-oxygenanthraquinone (SOAQ) pulping to investigate the silica content in pulp and black liquor. The results showed that 88.4% of the silica remained with the pulp in this process. In this study the oxide-added SOAQ pulping process was used to further enhance silica precipitation on pulp by adding 1 to 3% oxide such as Al{2}O{3}, CaO and MgO. The results indicated that the optimum oxide-added soda-oxygenanthraquinone pulping conditions for wheat straw were: alkali charge on o.d. raw material, 16%; anthraquinone (AQ) charge on o.d. raw material, 0.1%; Al{2}O{3} charge on o.d. raw material, 3%; temperature, 140 C; time at maximum temperature, 40 min; oxygen pressure, 8 kg/cm2 ( 0.79MPa); and liquor-to-straw ratio, 5:1. It was found that the oxide-added SOAQ process increased silica precipitation on pulps by about 9% compare to the SOAQ pulping process. It was concluded that the oxide-added SOAQ process gives the best precipitation of silica onto pulp and also gives good pulp physical and optical properties. The method offers a practical and radical solution to the silica problem.

Chitosan as a Surface Sizing Agent for Offset Printing Paper

Abstract: The biopolymer chitosan has been shown to improve the surface properties of paper for offset printing. The quality of the sized paper was investigated after treatment with chitosan of different molecular weights and different concentrations as well as in a blend with oxidised starch. The results were compared with the sizing quality of polyvinyl alcohol and oxidised starch. It was found that the molecular weight and concentration of the chitosan influenced the sizing quality. Blending of oxidised starch with a small quantity of chitosan significantly improved the sizing quality of the former. It was concluded that the chitosansized paper was superior for offset printing compared to paper sized with either oxidised starch or polyvinyl alcohol.

Effect of idealised flow conditions on retention aid performance. Part 2: polymer bridging, charged patches, and charge neutralisation

Abstract: Retention aids can affect papermaking process efficiency and product quality. The efficiency of these polyelectrolyte treatments may be affected by conditions of flow before and during sheet formation. Four contrasting retention aid systems were compared. Hydrodynamic shear before dewatering decreased the retention efficiency of very-high-mass acrylamide copolymers, consistent with irreversible breakdown of polymeric bridges. Such shear had little effect in the case of a moderately high-mass ethyleneimine copolymer. The relative effectiveness and responses to flow conditions of different polymeric treatments were consistent with concepts of charge neutralisation, charged patches, and two types of polymeric bridges. Flow velocity pulsations normal to the plane of the forming screen lowered the retention efficiency for all of the retention aid systems, though not as much as the application of uniform time-averaged shear stress to the suspension during dewatering.

Wood Resin 8 in Acacia mangium and Acacia crassicarpa Wood and Knots

Abstract: The lipophilic extractives, i.e. the wood resin, in Acacia mangium and Acacia crassicarpa stemwood and knots were analysed. A. mangium stemwood contained over 1% hexane-soluble extractives, whereas A. crassicarpa contained only 0.1 to 0.2%. The amount of lipophilic extractives was on the same level in stem heartwood and sapwood, while knots contained smaller amounts. Long-chain saturated fatty acids and alcohols, with 22 to 28 carbon atoms make up the major part of the extractives in A. mangium. A crassicarpa contains mainly short-chain fatty acids with 16 to 20 carbon atoms. It is concluded that special technical measures are required for A. mangium to remove the extractives from the fibres in pulping and bleaching and to keep them in a dissolved or colloidal state in the pulping and bleaching liquors.

Production of Paper Grade Pulp from Bagasse by a Novel Pulping Process

Abstract: A novel pulping process using formic acid/acetic acid/water to selectively separate cellulose, hemicelluloses and lignin from bagasse was optimised and the bleaching response and pulp properties were determined. The process is suitable for use with high silicon containing raw materials because the silicon predominantly stays with the pulp and does not complicate chemical recovery. Key pulping variables were the percentage of formic acid and water in the pulping liquor, the liquor to fibre ratio and pulping time. This cooking method produced unbleached paper pulp at atmospheric pressure. High quality bleached pulp was produced using a TCF sequence. This process has the potential to be very environmentally effective. Pilot scale evaluation is planned.

Mechanism of Chlorate Formation in Chlorine Dioxide Delignification

Abstract: The effect of pH on chlorate formation during chlorine dioxide delignification of oxygen delignified kraft pulp was studied. Chlorate formation was found to increase slightly when pH was increased from 1.8 to 2.5; further increase of pH decreased chlorate formation. The above phenomenon is explained by the combination of two mechanisms, one by the reaction between hypochlorous acid (HClO) and chlorite, another by the effect of chlorine on the regeneration of chlorine dioxide. The first mechanism suggests that chlorate formation would be highly dependent on HClO concentration, which decreases with increasing pH and causes chlorate formation to trend similarly. The second mechanism suggests that chlorine favours the regeneration of chlorine dioxide while HClO favours chlorate formation, thus lowering the pH from about 4 to the acidic extreme should decrease chlorate formation. The two opposite effects lead to the maximum formation of chlorate at around pH 2.5.

Effect of idealised flow conditions on retention aid performance. Part 1: cationic acrylamide copolymer

Abstract: The performance of a cationic acrylamide copolymer retention aid was evaluated with respect to five contrasting flow conditions applied either before or during the formation of a fibre mat. Different levels of pre-shearing of a simulated fine-paper headbox stock were applied after chemical addition, but before constant-rate dewatering. Dewatering conditions included simple filtration, flow pulsations of known amplitudes and frequencies of normal to the forming screen, and continuous stirring during dewatering either with an impeller or at a uniform time-averaged shear rate. Under all conditions of flow the retention aid reduced the turbidity of the filtrate, consistent with improved retention of fine materials. However, the effectiveness of the polymer was irreversibly decreased by high shear before dewatering. The irreversible loss was observed even when the slurry subsequently was subjected to vigorous flow pulsations during dewatering. Results were consistent with a polymer-bridging mode of retention aid action.

Within-Tree Variation of Detailed Fiber Morphology and Its Position Representing the Whole-Tree Value in Eucalyptus camaldulensis and E. globulus

Abstract: Eucalyptus is one of the major plantation species for pulp wood in many countries. It is of importance to breed trees possessing high pulp yield and quality for the management of pulpwood forests. The selection of elite trees based on their quality has become increasingly significant from both environment issues and the reduction of pulp cost, especially for plantations with short rotations [1]. In the quality breeding program, the increment core method is preferably performed [2]. However, this is an indirect selection method that estimates whole-tree properties using the relationships between wood and pulp properties and requires a core-sampling position that will represent the whole-value. Fiber morphology is an important determinant of pulp properties in Eucalyptus. We examined the within-tree variation and the representative height in the trunk to indicate whole-tree values of fiber morphology (length, radial, tangential and average diameters, lumen diameter, and wall thickness) in Eucalyptus camaldulensis and E. globulus trees [3].

Influence of eucalypt wood supply on pulp brightness stability

Abstract: One hundred different 5.5-year-old eucalypt wood clones were cooked to Kappa number 15 to 17.5 and the resulting kraft pulps oxygen-delignified to Kappa 9.5 to 11.5 under fixed conditions. Thirteen samples showing large variations in effective alkali requirement, pulp yield and O2-stage performance were selected for brightness reversion studies. These samples were bleached to 90 to 91% ISO. Heat reversion of the eucalypt kraft pulps was strongly influenced by the wood supply, with brightness losses of 2.1 to 3.6 and 0.8 to 1.7% ISO for ODEDD and ODEDP bleached pulps, respectively. Pulps bleached by the ODEDP sequence showed reversion values 1.3 to 1.9% ISO lower than those bleached by the ODEDD sequence. Pulp carbonyl content decreased by 35 to 40% during the final peroxide bleaching stage. Pulp carbonyl and carboxyl groups as well as permanganate number correlated positively with brightness reversion. Pulping, oxygen delignification and ECF bleaching performances showed no correlation with brightness reversion.

A Study of the Effects of Alkyl Ketene Dimer and Ketone on Paper Sizing and Friction Properties

Abstract: AKD, one of the most widely used sizing agents in neutral/alkaline papermaking, is reported to cause some problems to papermakers and paper end users. Calcium carbonate, if present in the furnish, is known to increase the AKD demand required to produce a desired sizing degree of the paper. Papers sized with AKD are often reported to lose their resistance to water penetration, which is known as sizing reversion. There have also been several reports that AKD sized papers experience problems with friction properties. Therefore this study was aimed at investigating the mechanism of AKD sizing and especially understanding the reason why and how AKD makes paper slippery.

Effects of polyamideamine-epichlorohydrin (PAE) resin deterioration on PAE retention and wet strength performance in handsheet making

Abstract: Handsheets were prepared with polyamideamine-epichlorohydrin (PAE) resin solutions stored at 4 C and pH 4.2 to 4.5 for up to 8.9 years, and the effects of structural changes of the deteriorated PAE on retention behaviour and wet tensile strength of the handsheets prepared thereof were studied. When stored PAE samples were used, wet tensile strength decreased with increasing PAE storage time. This decrease in wet tensile performance is partly explainable by the decreased PAE retention ratio, which is due to both decreases in 3-hydroxy-azetidinium content and DPn of the stored PAE. On the other hand, the decrease in wet tensile index of the handsheets at the same PAE retention ratio is probably due to the decrease in 3-hydroxy-azetidinium content of the stored PAE rather than the decrease in DPn. When PAE solutions are stored at 4 C, both their wet tensile performance and retention ability on pulp fibres are mostly maintained at least within 9 months.

The Influence of Refining Energy and Intensity on Enhancing the Bonding Potential of an OCC Pulp

Abstract: Old corrugated container (OCC) pulp was treated in a laboratory Escher Wyss refiner, with the emphasis on controlled energy usage and refining intensity. Some indicator strength properties, which could be translated into bonding development of the OCC pulp, were measured and compared with unrefined OCC pulp. It was observed that optimum refining could fully restore the bonding potential of OCC pulp without harming other papermaking requirements beyond the processing requirements or end-use stipulations. It was highlighted that for OCC pulp, refining intensity is insufficient to define the refining response due to the complexity of the refining process. Therefore, it was inferred that characterising the refining behaviour of different pulps based on intensity is an oversimplification.

Wet strength paper repulping: effect of process variables

Abstract: The repulping of wet strength paper with inorganic chemicals was investigated in the laboratory. The effects of major variables such as repulping time, pulp stock concentration, soaking time, temperature, and reactant concentration in the repulping stage were examined using a Plackett- Burman design. The repulping time was the most crucial and influential process variable affecting repulping characteristics and formation related properties. The other repulping process variables having a significant effect on pulp yield were soaking temperature and pulp stock concentration, whereas for formation index and feature-size, pulp stock concentration, soaking temperature and time were important variables. The formation index was increased by an increase in repulping time, pulp stock concentration and soaking time whereas the feature-size was decreased by an increase in repulping time, soaking temperature and pulp stock concentration. The formation index and the rejects were more sensitive to changes in process variables than the feature-size.

Glucuronoxylan-derived Chlorinated Compounds in Filtrates from Chlorine Dioxide Bleaching: A Comparative Study between Eucalypt (E. globulus) and Birch (Betula spp.) Kraft Pulps

Abstract: Eucalyptus globulus and Betula spp kraft pulps were submitted to a D0E1D1E2D2 bleaching stage and the ethyl acetate extracts of D filtrates analysed by GC-MS. In both species, significant amounts of glucuronoxylan-derived chlorinated compounds were detected, particularly in D0 and D1 stages, contributing 17 to 34% of the corresponding AOX. The influence of the nature of the glucuronoxylan of these two species in the amount of chlorinated derivatives formed is discussed.

Within-tree variation of vessel morphology and frequency, and representative heights for estimating whole-tree values in Eucalyptus camaldulensis and E. globulus

Abstract: Often vessels have a major effect on causing the paper properties of Eucalyptus [1, 2, 3] They are picked from the paper during printing, causing a non-uniform paper surface, which affects the distribution of ink [1] Vessel morphology and frequency are important selection indices in the quality breeding program for pulp production However, the most appropriate core-sampling position has not as yet been reported for vessel morphology and frequency on a whole-tree basis We examined and the representative height in the trunk to indicate whole-tree values of vessel morphology (length, radial, tangential and average diameters, and wall thickness) and frequency through the within-tree variation in Eucalyptus camaldulensis and E globulus trees [4]

How Does Mass Transfer Affect the Effectiveness of AQ

Abstract: Many researchers have studied the mechanism of the catalytic effect of anthraquinone (AQ) in pulping based on the fundamentals of chemistry, kinetics, and physical properties of AQ. The role of mass transfer was generally neglected in these studies. This paper describes our analysis and interpretation of published experimental data based on both chemical (kinetics) and physical (mass transfer) effects. This analysis has led to a proposed 'AQ uptake' mechanism that incorporates the mass transfer effects, and provided explanations for previously unexplained and/or under-explained phenomena, e.g. the fact that AQ is concentrated into wood chips in the early stage of pulping. Our explanation of the immobilisation of AQ molecules is that the reaction with lignin causes solid AQ to precipitate out of the liquid and deposit on interstitial chip surfaces. Acknowledgment of the role of mass transfer in AQ pulping could improve pulping conditions that can enhance the catalytic effect of AQ.

Effects of Application Temperature in Paper Surface Sizing with Temperature-responsive Starch on Water Repellency and Flexographic Printability

Abstract: This study presents an evaluation of the application temperature on water repellence and printability in surface sizing with starch. Two different types of potato starch were used: one conventional oxidised starch and one with hydrophobic and amphoteric modification. The level of hydrophobic modification (HM) was low; the degree of substitution (DS) of the hydrophobically modified starch grade was equal to 0.03. Due to the temperature-responsive character of the modified starch, the sizing operations were performed at room temperature and at 70 C. The surfaces treated with the HM starch gained in hydrophobic nature with increasing sizing temperature. A comparison between the oxidised and the HM starch showed that the HM starch gave better print quality as reflected in measurement of white dots. The results obtained indicate clearly that there is a potential to develop a low-DS HM starch for coating/sizing of papers and board where barrier properties and printability are demanded.

Sodium Borohydride Assisted Hydrogen Peroxide Bleaching Process for Mechanical Pulps

Abstract: Sodium borohydride can assist in improving the performance of peroxide bleaching of mechanical pulps. In this paper, we report the PR process, in which a small amount of sodium borohydride, along with sodium silicate is added to the pulp for a pretreatment, followed by the addition of hydrogen peroxide. It has been demonstrated that the PR process gives significantly higher brightness than the conventional peroxide process under otherwise the same conditions. The PR process is of particular interest for mills to produce mechanical pulps of very high brightness.

The Effect of Surfactants on Kraft Pulping of Pinus Pinaster

Abstract: In order to ascertain the influence of surfactants in the delignification of Pinus pinaster wood and the bleachability of the resulting pulps, 17 surfactants from four families of surfactants were tested, namely: cationic, anionic, non-ionic and amphoteric. The best results in terms of improved delignification, lower screen rejects and lighter coloured unbleached pulps were obtained with the non-ionic surfactants. When compared with the reference, these cooks exhibited a decrease of up to 6.2% in Kappa number and 39% in screen rejects, and up to a 9% increase in the unbleached pulps reflectance factor. The most promising surfactants in terms of reflectance factor were poly(ethyleneglycol) 1000-4%, block copolymer poly(ethyleneglycol) - poly(propyleneglycol) 1100- 4% and poly(oxyethylene) 100 stearyl ether-1%. It was also established that the use of surfactants as cooking additives did not influence the bleachability, but allowed savings of chlorine dioxide in the first bleaching stage (about 5.2%), with consequent environmental and economical benefits.

Application of an Experimental Design to Modelling the Hydrogen Peroxide Stage in TCF Bleaching of Eucalypt Pulp

Abstract: Eucalyptus globulus kraft pulp was bleached in a totally chlorine-free (TCF) sequence (OXZP). The P stage was modelled using a four-variable sequential statistical plan over the following ranges: 0.5 to 2.5% hydrogen peroxide on o.d. pulp, 1 to 3 h reaction time, 70 to 90 C temperature, and 0.2 to 2.2% sodium hydroxide on o.d. pulp. The models defined from the results obtained predicted variations in ISO brightness, viscosity and hydrogen peroxide consumption of 84.6 to 90.5%, 890 to 819 mL/g and 10 to 99% on o.d. pulp, respectively. The best results were obtained for reaction times and hydrogen peroxide charges in the higher values of the experimental area, and temperatures and sodium hydroxide doses in the medium values. The variable most strongly influencing the pulp properties was found to be the hydrogen peroxide dose. It is possible to obtain TCF bleached eucalypt pulp of brightness over 90% ISO and viscosities over 800 mL/g. Finally, the pulp, paper and effluent properties of the sequence were also studied.

Dual Effect of Foil Tip Speed on Reject Thickening in Pressure Screening

Abstract: The effect of foil tip speed on reject thickening was studied based on the online consistency meters mounted in the feed and reject line of the pressure screen. The effect was tested both with slotted and perforated screen baskets using two pulps (kraft and CTMP). Unexpectedly, the results showed that a gradual change in the foil tip speed did not affect reject thickening monotonically, but there was often a local peak in it. Whether a peak in reject thickening was found and what its magnitude was, depended on screen plate geometry, fibre type, aperture velocity, and stock concentration. Because there often seems to be an optimum rotor frequency found in regard to reject thickening in pressure screening, the operational rotor frequency chosen for use is not without significance.

Morphological properties of cellulose fibre recovered from municipal solid waste

Abstract: The morphology of cellulose fibre recovered directly from Municipal Solid Waste (MSW) for papermaking was investigated. A laboratory method for simulation of the fibre recovery process was developed (using a Parr reactor) and found to impart nearly the same increase in pulp freeness as a commercial steam autoclave. A variety of fibre types were processed in the Parr reactor and their morphological properties were determined. It was found that all pulps tested displayed an increase in freeness after processing, suggesting that the unusually high freeness of MSW fibre is a result of the recovery process. A similar trend was seen in the TAPPI draining time values of the various pulps, and that the draining time of MSW fibre was found to be nearly equal to that of OCC. A Fibre Quality Analyzer was used to compare the fibre length, fines content, kink and curl of MSW fibre to OCC. Before and after processing, samples of OCC and TMP were also analysed to determine what affect the process had on fibre morphology. MSW fibre was found to have a comparable fibre length to OCC, but a lesser amount of fines and a higher degree of fibre shape (kink and curl). It was also found that the recovery process increased the kink and curl for both fibre types. Consequently, it is concluded that the combination of a greater kink/curl and low fines content is the likely cause of the unusually high freeness of MSW fibre. In addition, it is also concluded that the recovery process is directly responsible for this freeness change.

Controlling Filler Distribution for Improved Fine Paper Properties

Abstract: In this study, the main target was to control the filler distribution in the paper thickness direction and to evaluate its influence on some basic fine paper quality properties. The study was based upon pilot paper machine trials using wet end additives layering principles together with normal headbox and former controlling parameters. A statistical approach to the experimental results was used to extract the parameters for the models needed. The main focus of the study was on 50 and 80 g/m2 woodfree papers. The results showed a clear dependence of the quality of the woodfree paper on the filler distribution characteristics. Asymmetrical filler distributions contributed to low porosity, while the minimisation of oil absorption differences between surfaces was promoted by symmetrical filler distributions. This was particularly true with higher grammage papers.

The Effect of Phosphonates on Kraft Pulping and Brown Stock Washing of Eucalypt Pulps

Abstract: This work studied the effect of phosphonates on kraft cooking of mixed eucalypt chips (predominantly E. grandis) and brown stock washing of the resultant pulp. Results show that DTPMPA (diethylene triamine penta methylene phosphonic acid) is effective in reducing metal ions when applied in brown stock washing, producing improved pulp physical properties compared to the control. SPAP (sodium salt solution of polyaminophosphonic acids) increased pulp physical properties when applied only in cooking, but it showed best metals removal when dosed in brown stock washing. Another phosphonate, known as HEDP (1-hydroxy ethylidene diamine 1, 1-diphosphonic acid), EDTA (ethylene diamine tetra acetic acid), and strong acid washing were compared with DTPMPA and SPAP. DTPMPA and SPAP addition did not produce significant differences in Mg, Cu and Fe content in pulps, but Mn was reduced to very low levels. HEDP did not produce any difference in metal ions content compared with an untreated pulp.

The Two-stage Oxygen Delignification of Hardwood Kraft Pulp

Abstract: Laboratory two-stage oxygen delignification was carried out to study the effect of reactor top pressure on the degree of delignification and to determine the rate constants of the delignification in each stage. In order to obtain a high degree of delignification, the oxygen charge should be split into each reactor and the temperature of the second reactor should be higher than that of the first reactor. When the pressure of the first reactor was increased beyond 500 kPa, the gain in delignification degree was small and both the viscosity and tear index were decreased. Kinetic study indicated that oxygen delignification is a two-phase reaction in terms of Kappa number, and the rate constant of the first phase, depending on the first reactor top pressure, is 5 to 7 times that of the second phase.

Extended Oxygen Delignification. Part I: Effects of Multi-stage Oxygen Bleaching on Softwood Kraft Pulp and Residual Lignin. Comparison with Chlorine Dioxide Delignification

Abstract: A softwood kraft pulp was submitted to successive oxygen stages (O, OO, OOO). Residual lignin after treatment was extracted by acid hydrolysis and characterised by 13C NMR and GPC. The progressive decrease in the efficiency of the O treatment in a multiple O sequence was explained by the poor reactivity of some of the free phenolic lignin structures with oxygen. Oxygen (O) and chlorine dioxide (D) delignification were compared. Contrary to OOO , the DEDEDE... process led to total delignification. Both chemicals attacked the free phenolic groups in lignin as evidenced by the important decrease in their number measured after treatment. However, their disappearance was more complete in the case of ClO{2}. Moreover a higher number of ClO{2} H groups were formed in the latter case. According to mechanisms given for chlorine dioxide delignification, hypochlorous acid (ClOH) is produced as by-product during a D stage and would react with residual lignin. This would explain the better efficiency of D compared to O stages.

The Effect of Green Liquor / Anthraquinone-modified Kraft Pulping on the Physical and Chemical Properties of Hardwoods

Abstract: Modified kraft pulping of hardwood for the manufacture of linerboard grade pulp by using green liquor (GL) was investigated. The combination of GL and anthraquinone (AQ) to improve pulp qualities are discussed. More than 2 absolute percentage points of pulp yield increase was achieved by addition of AQ in the GL pretreatment at a Kappa number of 107 to 110. Furthermore, GL/AQ pretreatment modified kraft pulping also provided additional benefits in chemical savings and energy reduction. Approximately 23 to 26% of alkali saving and a lower H-factor compared to conventional kraft pulping were obtained in this modified kraft pulping process. The results indicate sulfide concentration in the post cook can play an important role on AQ function during pulping. A greater effect for AQ in GL pretreatment was achieved at a lower rather than higher sulfidity. The physical strength of the modified kraft pulp was also quite similar to conventional kraft pulp.

The Use of Deinking Rate and Cleaning Rate: To Evaluate Deinking Plant Performance

Abstract: In this study, deinking efficiency, deinking rate, cleaning efficiency and cleaning rate were used to evaluate the efficiency of equipment and stages in commercial deinking lines. The effective residual ink concentration (ERIC), and flakes (dirt) by image analysis were determined, and deinking efficiency, deinking rate, cleaning efficiency and cleaning rate were calculated as measures of plant performance. The results showed that deinking rate and cleaning rate were the most effective and convenient tools for characterising the efficiency of equipment and stages in deinking lines.

Comparison of Chemical and Chemimechanical Pulps from Hardwoods

Abstract: Chemical and chemimechanical pulps, and mixtures of the two from different hardwoods were investigated for their intrinsic and other pulp properties. The results showed that chemimechanical pulps from hardwoods, like P-RC APMP, can be as strong as their chemical pulps, and have higher tensile at the same density, or higher bulk at the same tensile, compared to their chemical pulps. Adding up to 20% of hardwood (aspen) chemimechanical pulp to aspen chemical pulp improved the pulp intrinsic properties, and the resultant pulp blends had a higher fibre bonding (tensile and tensile energy absorption) than the sum of weighted contributions from their individual components. This synergistic effect between the chemical and the chemimechanical pulps may assist in improving their application and performance in papermaking processes.