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MWV Forestry has been actively pursuing the establishment of cold- and frost-tolerant eucalyptus plantations in southeast Texas and in the higher, frost-prone regions of southern Brazil for several years. Currently, the major species being examined is Eucalyptus benthamii. Interspecific crossing efforts, cold tolerance established from field trials, and intercountry cooperation in this program are discussed. The ability of the southeastern Texas program to return value to our collaborators in southern Brazil and other locations is reviewed. Pulp and papermaking properties of the cold-tolerant species are also reviewed. Currently, E. benthamii plantations in southeast Texas are producing trees with a density range of about 460-523 kg/m3, suggesting some degree of genetic variability within the bulk seeds currently being employed. Good pulping yields of around 48% on o.d. wood have been obtained in laboratory studies. For comparison, this yield is about 3 percentage points higher than for traditional mixed southern hardwoods. In general, the physical properties of pure E. benthamii are inferior to those of mixed southern hardwoods. When used in a blend, the differences in physical properties are substantially mitigated. [ABSTRACT FROM AUTHOR]

A flotation process and two different heat treatment processes prior to pulping were investigated according to their ability to remove mineral oils. For flotation, a correlation between removal of mineral oils and inorganic particles could be found for all process chemicals used in this study. By optimization of chemical concentration and dosing sequence, up to 80% of mineral oils could be removed while keeping the total losses smaller than 15%. The heat treatment processes achieved mineral oil removal rates that were in some cases even higher than those for flotation. For these processes, the most important parameters appeared to be the specific energy applied, the temperature, and the particle size distribution of recovered paper components. However, the specific energy consumption was quite high. Application: This study shows the possibilities for removing mineral oil in recovered paper processing at laboratory scale. Besides conventional processes, treatments with hot air and steam were used with success. [ABSTRACT FROM AUTHOR]

Eucalyptus plantations have been used as a source of short fiber for papermaking for more than 40 years. The development in genetic improvement and clonal programs has produced improved density plantations that have resulted in fast growing, increased fiber volume eucalypts becoming the most widely used source of short fibers in the world. High productivity and short rotation times, along with the uniformity and improved wood quality of clonal plantations have attracted private industry investment in eucalypt plantations. Currently, only a handful of species or hybrids are used in plantation efforts. Many more species are being evaluated to either enhance fiber properties or expand the range of eucalypt plantations. Eucalyptus plantations are frequently planted on nonforested land and may be used, in part, as a means of conserving native forests while allowing the production of high quality fiber for economic uses. Finally, eucalypt plantations can provide significant carbon sinks, which may be used to help offset the carbon released from burning fossil fuels. The development and expansion of eucalypt plantations represents a substantial revolution in pulp and paper manufacturing. Application: By understanding the breeding and clonal developments that have occurred in the past and the results of those developments, the industry may be better equipped to rapidly advance the next stage of eucalypt progress. [ABSTRACT FROM AUTHOR]

Oat β-D glucan was treated with 3-chloro-2-hydroxypropyl-trimethyl ammonium chloride (10%, 20%, 30%, or 50% of beta glucan) to obtain a range of cationic β-D glucan samples. The derivatization was confirmed by the results of Fourier transform infrared (FTIR) tests and elemental analysis. Addition of 1% cationic β-D glucan based on the mass of unbleached pine kraft fiber increased burst, tensile, and folding endurance properties of the resulting paper. Similar effects were observed at pH 5 and pH 8.5, showing that the system can be considered robust relative to typical acidic and alkaline papermaking conditions. The strength benefits were also observed in recycled sheets made by reslurrying paper prepared with cationic β-D glucan, even when the initial drying conditions had been severe. The beneficial results of cationization, which can be explained by a more hydrophilic nature and better retention, hold promise as a means of improving the strength properties of virgin paper. The treatment of the initial paper also can enhance the dry-strength performance when the fibers are recovered and used again. Application: Treating a hemicellulosic byproduct of oat processing to give it a positive charge can improve its effectiveness as a dry-strength agent for wet-end addition. [ABSTRACT FROM AUTHOR]

Bamboo is one of the world's fastest growing feedstocks and represents a promising nonwood resource that can be utilized in the pulp and paper industry. The timber varieties offer low feedstock costs, can be processed similarly to trees from a logistics standpoint, and have useful fiber properties for papermaking. Plantations have not yet been established due to propagation costs, limiting adoption of bamboo as a pulp feedstock to smaller pulp mills primarily in China, where there are native forests. Recent advances in micropropagation may allow lower establishment costs, but gradual introduction into the supply chain will be required. One concept is to gradually include bamboo feedstock into an established pulp mill as plantations are established, using co-cooking with a wood species. Previous work has shown that bamboo cooks fairly easily using the kraft process with conditions similar to hardwood species. Application: Producers considering adopting bamboo fiber as a portion of their fiber furnish for economic, unique property, or marketing reasons could utilize a strategy of co-cooking bamboo with either poplar or eucalyptus. [ABSTRACT FROM AUTHOR]

Mineral fillers are added during papermaking to improve the optical and printing properties of paper and decrease energy costs. Filler loading using conventional approaches has some disadvantages, such as reduction in paper strength. The finer filler, the more the strength loss. Several methods and materials have been reported to overcome or alleviate the same, but with higher costs. Our approach provides an economically viable solution to the problem, using conventional papermaking materials. Talc filler of different particle sizes, preflocculated using different doses of cooked amphoteric starch, were used for papermaking. Relatively higher filler retention, paper strength, and hydrophobicity of paper were obtained with preflocculated talc compared to native talc. The optical properties of paper were unchanged on the loading of similar talc after preflocculation. The preflocculated talc of finer particle size provided higher opacity at similar ash, as well as paper strength, than the native talc of coarser size. [ABSTRACT FROM AUTHOR]

A potential biorefinery is envisioned to use the hemicellulose portion of biomass to create transportation fuels or chemicals and the cellulose portion for fiber to be used in papermaking. To understand the effect on hemicellulose removal to pulpability and bleachability, a liquid hot water extraction was performed on two types of biomass with high hemicellulose content: poplar and miscanthus. The resulting materials were pulped using either a soda anthraquinone or kraft process. The pulps were then oxygen delignified and bleached with an elemental chlorine free sequence. The results demonstrate that a significant portion of hemicellulose can be extracted using liquid hot water extraction conditions of 170℃C, 60 min, and a 6:1 ratio, with minimal glucan degradation. These low hemicellulose- content pulps delignified similarly to the control pulp, but had lower oxidative demand because of the absence of hemicellulose degradation products. Oxygen delignification of the low hemicellulose-content pulps was enhanced, but so was cellulose degradation. The delignification gains resulted in higher brightness ceilings for the pulps when a D(EP)D sequence was used. Measured fiber morphology did not change significantly from extracting the hemicellulose. Overall, hemicellulose extraction before pulping improved the efficiency of pulping and bleaching materials to a high brightness, but increased cellulose degradation. [ABSTRACT FROM AUTHOR]

During sheet forming, the structure of the forming fabric leaves wire marks on the pulp mat. Paper nonuniformity caused by the wire mark can lead to ink nonuniformity in printing. We investigated wire mark numerically through simulations of the interaction of individual fibers with a forming fabric. In the simulations, the flow field through the forming fabric was taken to be that of single-phase water flow without disturbance of fibers. A particle level simulation method was applied to simulate the motion of fibers in the flow through a single layer sine-wave fabric. A hundred fibers of random initial distribution were placed into the flow above the fabric. Those fibers were adverted onto the fabric, forming a fiber mat. The surface roughness of the resulting fiber mat was then calculated. The results show that during the initial formation, topographic wire mark is caused partially by fiber bending and partially by the geometry of the fabric. For the specific fibers and sinusoidal forming fabric considered, more than 50% of topographic wire mark is the result of geometry, with the remainder attributed to fiber bending. Fabrics with different geometries (e.g., different filament pitches or a nonsinusoidal geometry) will have different relative influences from geometry and fiber bending. [ABSTRACT FROM AUTHOR]

The method of fractal analysis was applied to study different types of printing papers with respect to their offset printability and the relationship between paper properties and fractal characteristics of unprinted and printed area. Fractal analysis of captured digital images of samples was done using a box counting method. For each sample, four fractal parameters derived from fractal dimensions were determined. Results show that fractal characteristics chosen reflect the properties of individual types of printing papers and corresponding printed offset ink layers. Correlations of fractal parameters with the thickness of ink layer, optical density of printed samples, and paper roughness are discussed in detail. [ABSTRACT FROM AUTHOR]

A new Two-Sided Drainage Handsheet Machine (TSDHM) was developed and compared to the Standard British Handsheet Machine (Standard Machine). The results show that fines and filler distribution in hand-sheets produced in the one-sided drainage mode by the TSDHM closely mimics the fines and filler distribution of the Standard Machine. When the drainage was reversed on the TSDHM from the classical 100% bottom to 100% top, the fines and filler profiles in the handsheets could be reverted. The two-sided drainage mode on the TSDHM can produce fines and filler profiles across the paper thickness that are completely different from the one-sided drainage mode. These profiles are more representative of top and twin-wire formers. [ABSTRACT FROM AUTHOR]

This work was a comprehensive study of the properties of extracted Eucalyptus globulus kraft pulps. Five levels of hot water extraction were performed, each followed by kraft cooking to three different kappa numbers. As extraction took place, the hemicelluloses content of the kraft pulps was reduced from 21%-22% to 3%-4% and, conversely, the cellulose fraction increased from 73%-75% to 85%-90%. Fiber length decreased for all pulps and kink index increased greatly with extraction. The dispersive components of the surface energy for the control (unextracted) and extracted (120 min) kappa no. 15 kraft pulps, as determined by inverse gas chromatography, were found to be 30.8 and 34.9 mJ/m2, respectively. The acid-base properties of the pulp surface seemed to be enhanced by the inclusion of the hot-water extraction step. We discuss the surface energy properties in terms of the chemical structure of the pulps. In addition, we report on two models able to predict the mass removal and kappa number of pulps prepared from preextracted chips. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Increasingly stringent environmental standards and market demands are forcing pulp and paper mills to minimize both their water usage and their effluent discharge. Higher rates of process water reuse in pulp and paper mills leads to increase amounts of dissolved and colloidal substances in process water, which is a major factor limiting further closure of the water circuits. This study explores the use of different types of talc as control agents for dissolved and colloidal material contained in white water from paper mills using recovered and coated paper as raw materials. It also identifies the kinds of talc that can be used to control detrimental properties of the whitewater. [ABSTRACT FROM AUTHOR]

Sting paper into compatible grades is a necessary step before recycling. Current methods of manually sorting are tedious, slow, andexpensive. High-speed automation of the sorting process will improve the cost efficiency and increase the amount of paperrecycled significantly. Correct identification of the sample in real-time before the sample reaches the actuation stations till remains a challenge because different types of paper and board samples are mixed in a waste stream, and have a lot of variation in terms of color, chemical composition, coating, and printing in black and white and color to different degrees. This primarily is because of a lack of satisfactory sensors and sensor fusion algorithms for sample identification in real-time. In this paper, we identify key parameters that must be measured, discuss a sensor system design, and describe integration of the output from sensors to interpret the type of sample using a fuzzy inference algorithm. Results show that the sensor system proposed is capable of identifying the samples at 90% accuracy compared to manual identification. The sensor system can be integrated onto a conveyor and a ctuation system for automated sorting. [ABSTRACT FROM AUTHOR]

A new Image analysis-based instrument has been developed for measurement of low density and high density macrocontaminants from recycled pulp or whitewater. The unit is coupled to a pulp classifier that isolates the contaminants from pulp and concentrates them before their transfer to a specialized chamber that further separates the contaminants based on their relative density to water. The low density contaminants float on the water surface, whereas the high density macrocontaminants sink onto the settling plate, where images of both contaminant types are then captured and analysed. Through image analysis, the high density contaminants are further classified into two categories: contaminants that are whitish in color and mainly comprised of stickies are named heavy stickies, whereas contaminants that are blackish in color and comprised of black toners and dark wood components are named dirt. When operating in the online mode with autosamplers delivering the samples to the pulp classifier, the instrument provides macrocontaminant determinations every 15 min. The total count and surface area of both types of macrocontaminants per kilograms of pulp can then be sent by direct link to the mill data control system, allowing an effective follow-up of macrocontaminant changes in process pulps and waters. The unit also allows the user to view images of the contaminants. The analyzer results obtained in terms of number and area of macrocontaminants show a linear relationship with TAPPI T-277 om-07 "Macro stickies content in pulp: the 'pick-up' method." [ABSTRACT FROM AUTHOR]

The article reports that surface strength is important for uncoated woodfree papers, as it minimizes dusting phenomena in offset and electrophotographic printing process. It states that the paper were produced with and without surface sizing, with different filler types, ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC), and levels, and by varying the calendaring conditions.

The article discusses the study conducted by the research team from the Institute of Paper Science and Technology at Georgia Institute of Technology and Imerys to advance application of starch-encapsulated papermaking fillers in the U.S. The study illustrates that starch-encapsulated fillers can facilitate a near-doubling of filler content compare to conventional levels at equal tensile and z-direction tensile (ZDT). Also mentions is the ability of SEK to function as a fiber extender.

The article presents a study which examines the anatomical, chemical and morphological characteristics of Anthocephalus cadamba and its suitability in pulp manufacture. Findings reveal that the tropical hardwood can produce high pulp yield at milder preparation time and temperature making it a suitable material for pulp and paper production. It also indicates that the wood-pulp can develop an optimal strength of up to 44 Schopper-Riegler degree (°SR).

The article presents a study which adopted a computational fluid dynamics (CFD) model for a papermaking mixing procedure to disperse synthetic fibers in wet-lay process. It states that a discrete phase model was developed by placing spherical particles in the flow after a converged solution was obtained for the mixing tank with water. Findings reveal that CFD model can be utilized to achieve an efficient mixing tank design for wet-lay fiber dispersion.

The article presents a study that examines the papermaking potential of novel structured precipitated calcium carbonate (PCC) fillers with enhanced refractive index. It notes that moderate structuring was being examined which comprised introduction of optically effective fine particles on conventional scalenohedral PCC host particles. The results revealed beneficial light scattering and that property balance decreased the advantage.

The article examines key factors underlying paper curl and diagonal curl and provides a measurement method for evaluating diagonal curl. It notes that this methodology dominates most of limitations of existing methods and is being implemented in a paper mill. It discovers that diagonal curl measurements correlate well with the occurrence of paper jams.

The article discusses the development of equations to estimate relative changes in fiber trapping behavior and shows how fiber trapping affects the refining process. It defines fiber trapping in refining as the fraction of bar edges which trap fibers as they cross. It discovers a reduction in the number of fibers trapped under each section of bar and that this reduction in fiber trapping increased forces on fibers.

The article presents the research which studied the application of carboxymethyl cellulose (CMC) to mixed pulp slurries for wood-containing paper production. The results indicates that some mechanisms asides from enhancement of rosin size retention may have brought about the clear improvement of sizing performance by the CMC addition. The changes in distribution of rosin size components or some structural changes may be candidates for sizing development. It further states that sizing performance of wood-containing grades with alum and rosin dispersion size can be improved by 0.1% CMC addition at the wet end.

The article discusses the study on the utilization of modified talc as internal treatment for papermaking. It states that talc has been modified chemically with starch, carboxymethyl cellulose, glycerol, and polyacrylamide in the study. It mentions that results of the study shows that modified talc gives higher results when used as internal treatment for papermaking compared with native talc. In addition, results indicate that modified talc enhances the mechanical and optical properties for filled or coated handsheets. Moreover, talc modification improves filler-fiber-filler bond.

The article focuses on the significance of the pressurized high temperature black liquor gasification in improving the efficiency of the energy and chemical recovery cycle in kraft pulping. However, measurements of quantities to validate the current model validation are difficult to obtain because of severe conditions in the gasifier. Successful development of a computational fluid dynamic model will further the development of black liquor gasification, leading to improved efficiency of the energy and chemical recovery cycle in kraft pulping.

The article discusses a research which aims to determine the influence of pulp properties on the adsorption of cationic starch in paper manufacturing. It states that cationic starch is one of the most frequently used additives in the paper industry. It notes that hardwood fibers, more cationic starch are absorbed than to softwood fibers. In conclusion, it mentions that properties of fibers depend on their origin and treatment processes. However, it states that there is also a downside of refining which may result in the deterioration of end-product mechanical properties.

The article discusses a study on nitrogen oxide (NOx) formation in recovery boiler in paper making. It states that the study uses a methodolgy of computational fluid dynamics (CFD) combined with a detail reaction mechanism. It mentions that in investigating the origin of nitrogen emissions in this study, they carried out the CFD analysis of a black liquor using a highly detailed model. In conclusion, it mentions that black liquor spray characteristics play an important role in paper making. However, it states that increasing the average particle diameter has an opposite effect.

The article discusses the utilization of fractionation and refining in tailoring softwood kraft pulp properties in manufacturing paper. It notes that the materials used in this experimental methodology include softwood kraft pulp, conical filling, and narrow-bar disc filling. In conclusion, it mentions that fractionation indicates better potential for softwood pulp for different paper products. In addition, it states that the said methodology will benefit certain facilities interested in manufacturing softwood pulp fibers into different paper grades.

The article presents an experimental study on the use of pulverized coal fly ash as a wet end filler in papermaking. A major by-product of thermal power plants, large amounts of fly ash are dumped close to power plants which can cause environmental pollution specially when mixed to air, water, and soil over several hectares of land. According to the report, paper samples with fly ash were superior compared to kaolin clay which are commonly use as filler. It has a wide variation in particle size such as those from the burning of pulverized coal which has very fine particles and it acts as an inert material in papermaking process. The author states that this is the first evaluation of fly ash possible use in paper industry.

The article discusses the experimental study on the use of fly ash, major by-products of thermal power plants as wet end filler in papermaking. According to the author, the effects of fly ash addition as compared to those of kaolin clay is more superior. Fly ash obtained from burning of pulverized coal are dumped close to power plants creating environmental pollution. It has a wide variation in particle size and acts as an inert material. The author added that this is the first evaluation of the possible use of fly ash in paper industry.

The article presents an experimental research on the effect of eucalyptus globulus wood density on papermaking potential. It states that understanding the morphological features of eucalyptus globulus in tree selection and genetic improvement programs can help papermakers keep off the negative impact on light scattering coefficient and refining energy usage. Eucalyptus globulus kraft pulp has been used for printing and writing papers because of its strength, bulk, opacity, and smoothness. Different charts reflecting provenance, temperature, climate conditions and density of the wood are shown. It also includes diagrams showing the correlation between paper density and wood basic density, and the results and conclusions obtained from the study.

The article presents an experimental research on the process to produce high-quality precipitated calcium carbonate (PCC) by the causticizing process in a kraft pulp mill. It states that the purpose of this study is that rotary lime-kiln operation could also be cut down or avoided, and the consumption of fuel oil and consequent discharge of carbon dioxide gas could be decreased. PCC, which is produced mainly by the carbonation process, has been used widely as a paper filler due to its brightness and opaqueness effects, and its low cost. Included also are the experimental procedures, schematics of the causticizing process, photographic views of the various shapes of causticizing calcium carbonate, and the derived results and discussions.

The article focuses on the experimental research on the chemical and mechanical techniques for improving the papermaking properties of jack pine thermomechanical pulp (TMP) fibers. It states that through this study, the papermaking mills could avoid the consumption of reinforcement chemical fibers in papermaking when using mechanical fibers. The forecasted shortage of supply in traditional softwoods has drawn pulp producers in Quebec to use less desirable softwoods like jack pine. The materials needed, schematic plan, charts which show the effects of beating and condition of pulps after beating, and the results and conclusions derived are thoroughly discussed.

The article presents an experimental research on the continuous time domain characterization of mixing in agitated pulp chests. It states that this study can help engineers to consider the use of new characterization algorithm in improving the design and performance of agitated pulps for better paper quality and machine efficiency. The authors point out that mixing is to be highly considered in stock blending, consistency control, chemical generation, and deinking. Included are mathematical models showing a flow diagram of mixing, optimization problem presentations, and the associated solutions. It also mentions that anticipated results were based on the inherent limitations of the discrete-time approach.

The article provides information on a diffractive gloss meter for the measurement of local gloss of papers and prints. It mentions that specular gloss is widely used in the paper industry in order to examine surface quality. The measurement of minute changes in local gloss has not been offered in international standards because there is no enough suitable gloss meters. The studies of local and average gloss from papers and prints with the use of a highly sensitive diffractive gloss meter (DOG) gave information on both local and global gloss that can assist papermakers in optimal paper surface quality research and development.

The article examines the standard TAPPI gloss and microscale gloss of several commercial coated papers. The laboratory coated samples used in the study contain seven varieties of kaolin clays and four ground calcium carbonates with a wide variety of pigment morphology, particle size, and particle size distribution. In the study, the samples were calendared at different conditions. After the method, coated paper samples were found to have optically rough surfaces with Rayleigh parameter larger than one. The gloss of coated samples was tested with the use of a semi-empirical approach. The study suggests that gloss is predominantly governed by the surface texture paper despite large variations in the pigment size, morphology, and calendaring conditions.

The article focuses on the measurement of fiber flexibility of mechanical pulp with confocal laser scanning microscopy based on Steadman's method. Pulp fibers are wet pressed and bent over a glass wire. The flexibility of the fiber is expressed as the reciprocal of bending stiffness. It was found the fiber's flexibility is correlated well to interfiber bonding strength and sheet structural properties. A bleaching or refining process increases the fiber flexibility through altering the fiber wall's elastic modulus.

The article examines the difference of a black liquor spray from gas-assisted atomizer. It considers the droplet size, droplet size distribution, droplet size history, and the effects of a high-temperature environment on the process. Gas-assisted atomization produces a distribution of droplet sizes similar to distributions for water and other liquid. The droplet shape and size should be considered when modeling the spray or designing a gasifier system. Droplet formation and size can be affected by high temperature in a furnace environment.

The article examines the connection of the structural characteristics of coated papers to the occurrence of print mottle using imaging reflectometry. The mottle of a printed paper refers to the visible uneveness in print gloss or density. Homogenous coating structures are important to obtain mottle-free printed papers. The propensity for mottle correlated with the degree of porosity variation of the coating. To reduce print mottle, the coating porosity variations should be reduced by good coverage of the basepaper by the coating.

The article examines the optimal bleaching of kraft pulps made from red oak chips with different alkali charges. When the pulp is bleached with a kappa factor of 2.0, the brightness of the pulp emerging from this stage can be accurately predicted from the brightness of the pulp entering such stage. It was found that the combination of high effective alkali and high kappa factor gives pulp with a higher final brightness ceiling that any other combination. The combination of low effective alkali and low kappa factor is the most economical for brightness targets of 91 or lower.

The article presents a study assessing the impact of thermomechanical pulp (TMP) refining line interruptions and reject refiner operations on pulp and paper variability in Eastern Canada. The study highlights the problem of an Eastern Canadian newsprint mill, experiencing variability in paper strength and porosity. To explain quality fluctuations in pulp and final newsprint, the study undertakes a straightforward method for combining individual TMP operations into a single statistical model. It then focuses on determining the process fundamentals in a newsprint mill, targeting its specific energy and refining intensity. Findings shows how frequent interruptions in refining lines had affected the reject refining specific energy and other key parameters.

The article discusses the study on the effects of sheet moisture and calendar pressure on precipitated calcium carbonate (PCC) and ground calcium carbonate (GCC) coated papers. It cites that the narrow distribution coating PCC allows high moisture calendaring no loss of optical properties of coated papers. It indicates that the broad particle size distribution pigments exhibit a significant loss of optical properties, when, moisture increases and supercalendaring pressure is adjusted to achieve a gloss target. The study shows that narrow distribution coating PCC produces high micro-smoothness even in the absence of supercalendaring. It also suggests that one concept for achieving increased productivity is through a coating that would require less drying via pigment selection.

The article discusses the comparison between chemical pulps and chemical mechanical pulps from different hardwoods. It states that the combinations are made separately and in combination with the two types of pulps. The results show that hardwood chemical pulps like preconditioned refiner chemical alkaline peroxide mechanical pulp (P-RC APMP) can be developed to be as strong as chemical pulps. It indicates that the synergistic effect between the two pulps may be used to improve papermaking processes and their paper and paperboat products.

The article offers an investigation of the affect of additional neutral sulfite abaca pulp to the paper strength properties of softwood pulp. The author says that the addition of abaca increases the tearing resistance, folding endurance, fracture roughness and isotropic air permeability of handsheets of a softwood kraft pulp. The article also discusses the methodology of the study as well as the abaca processing and its components including caustic soda and alkaline sulfite. Tables and charts showing the properties of the pulps, tearing resistance and dewatering resistance functions of abaca on different variables are also provided.

The article examines the power consumption distribution in the first and second stages of a thermomechanical pulp refiner. The section studies the power consumption in a second stage refiner and calculates the power consumption distribution for the first and second stages. It reveals that the power consumption in a second stage refiner increases along the radius, while in a first stage refiner, the distribution is more even. It states that the innermost part of the second stage refiner seemed to work with a very low energy consumption, compared with the outer parts.

The article examines the factors contributing to improved environmental performance in the Finnish kraft pulping industry. The section describes the environmental significance of kraft pulping technology developments in Finnish kraft pulp mills. It presents the main interactions between technology development and environmental performance, particularly water emissions, air emissions, and energy. It states that supporting technology and core technology were found to be equally important in reducing the environmental loads from kraft pulp mills.