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Contents of Nordic Pulp & Paper Research Journal
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Nordic Pulp & Paper Research Journal (NPPRJ) is an international scientific magazine covering science and technology for the areas of wood or bio-mass constituents, pulp and paper and including new fiber-based materials, recovery and by-products from pulping processes, bio-refining and energy issues. Articles meeting required scientific standards are accepted from any continent.
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The latest issue of NPPRJ includes the articles as shown in the Table of Contents below.
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Clicking on a title will expand the information and the display will show Area, Title, Author(s), Abstact, Issue information, Page information, DOI, Keywords and link for buying the full article. Clicking a second time on the title will collapse the display again.
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Any article may be purchased by credit card as a pdf file to be downloaded within 24 h at a price of 22 EUR per article. (Value added tax may apply depending on your location, which you enter at payment logout.)
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Contents of Volume 28, 2013, Issue No. 1
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NORDIC PULP AND PAPER RESEARCH JOURNAL UNDER NEW MANAGEMENT
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Elisabet Brännvall, Editor-in-chief
Per Stenius, Scientific editor
Per Engstrand, Publisher
Lars Wågberg, Chairman, Editorial Board
The ownership of NPPRJ was taken over by Mid-Sweden University, Sundsvall, Sweden on January 1, 2013. The journal is now run as a project with four Swedish, three Finnish and one Norwegian University as participants in the project and they all have members of the editorial board – please also visit our website or cover page of the journal for the complete list of board members and members of our scientific advisory board.
Apart from having the same scientific Editor and Editor in Chief the journal is now directly supported by scientists deeply engaged in research inspired by the present efforts to increase utilization of forests not only for construction and paper products but also as sources of environmentally sustainable raw materials that may replace materials now based on the use of fossil resources.
Since its start-up in 1986 NPPRJ has endeavoured to publish peer-reviewed articles in the field of pulp and paper science of direct relevance to the forest products industry and of the highest possible scientific quality. We are convinced that the change in ownership makes it possible for us to continue to do so, facing the dramatic changes in emphasis of research and development of commodities and advanced forest products that is presently taking place.
In conjunction with these changes we have undertaken a thorough overhaul of our website and its visibility in databases and search engines, so that the site now meets the demands of an up-to-date scientific journal. Thus, among other things, articles are now published on the web as soon as they have been finally approved for publication, all issues of NPPRJ since its start in 1986 are available for free for subscribers and for downloading at a moderate cost by anyone, and the full text of all articles is searchable, which we believe is a rather unique feature.
We hope that you will find NPPRJ a scientifically interesting, technologically stimulating and generally important journal – and we look forward to your manuscripts that are essential for us and will help us to maintain and improve the scientific and technological status of the journal.
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8TH INTERNATIONAL PAPER AND COATING CHEMISTRY SYMPOSIUM, 2012
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Topo-chemical modification of fibres by grafting of carboxymethyl cellulose in pilot scale
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Mikael Ankerfors, Elisabeth Duker and Tom Lindström
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Abstract:
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The aim of this study was to graft carboxymethyl cellulose (CMC) on to bleached softwood kraft pulp at temperatures below 100°C and to do a pilot paper machine trial in order to examine the influence of the CMC on dewatering, sheet formation and mechanical properties.
During the pilot trial, one CMC grafted pulp was compared to a pulp with 3 different refining degrees.
It was shown that CMC-grafting improves the mechanical properties of paper with only a minor effect on the sheet density. It was also shown that the CMC grafting is less detrimental to dewatering than refining and at a certain tensile index a higher dry content after pressing could be reached. The formation number of the paper produced in the FEX trial was not significantly affected by the addition of CMC.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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006-014
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DOI:
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10.3183/NPPRJ-2013-28-01-p006-014
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Keywords:
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Carboxymethyl cellulose (CMC), Carboxymethylation, CMC, Fibre flocculation, Grafting, Process integration, Sheet formation
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8TH INTERNATIONAL PAPER AND COATING CHEMISTRY SYMPOSIUM, 2012
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Effect of a new cationic-polymer/CMC bilayer-treatment on paper wettability
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Besma Ben Fadhel, Jean-Pierre Joly, Evelyne Mauret and Yves Chapleur
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Abstract:
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New cationic polymers were synthesized via radical cyclopolymerization of quaternary diallyl-ammonium monomer salts in a microwave reactor. Co-polymerization was ascertained by 1H- & 13C-nuclear magnetic resonance, differential scanning calorimetry, and average molecular weight estimated via size-exclusion chromatography.
Conventional handsheets made from bleached kraft pulps were impregnated with aqueous solutions of selected quaternary ammonium polymers and dried.
The hydrophobicity (i.e. dynamic water contact angle, wettability) of samples was significantly enhanced by a bilayer treatment with CMC in the external layer at the saturation level.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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015-021
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DOI:
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10.3183/NPPRJ-2013-28-01-p015-021
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Keywords:
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Bilayer treatment, Carboxymethyl cellulose (CMC), CMC, Paper wettability, Quaternary ammonium polymers (QAPs)
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8TH INTERNATIONAL PAPER AND COATING CHEMISTRY SYMPOSIUM, 2012
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Silica pigment produced from silicate mining sidestreams for ink-jet paper coating application
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Eija Kenttä, Taina Lamminmäki, Hille Rautkoski, Sebastian Teir, John Bacher, John Kettle and Juha Sarlin
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Abstract:
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Ink-jet printing technology is expected to continue growing, but cheaper silica pigment formulations than those currently available on the market will be needed for it to be commercially viable. The target of this work, part of the EU FP7 project ProMine, is to study the possibility of generating low-cost silica pigment from silicate mining industry sidestreams for use as a coating pigment for ink-jet paper. The worldwide resources of olivine are abundant and olivine is one of the main minerals in the dunite deposits in Greece. In this study silica is produced from Greek olivine silicate mineral by an acidic dissolution method. The pigment and coating layer properties of produced silica are compared to commercial silica pigments.
The laboratory scale study shows that the coating of produced silica pigment has ink-jet ink absorption speed and pore structure close to commercial precipitated silica coating. Produced silica pigment coated papers are matt, having very low gloss. Results show that produced silica pigment has potential for use as matt ink-jet coating pigment.
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8TH INTERNATIONAL PAPER AND COATING CHEMISTRY SYMPOSIUM, 2012
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Gloss, hydrophobicity and surface texture of papers with organic nanoparticle coatings
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Pieter Samyn, Jürgen Van Erps, Hugo Thienpont, Gustaaf Schoukens, Dirk Stanssens, Leo Vonck, Henk Van den Abbeele
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Abstract:
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We present an eco-friendly and sustainable alternative for common waxes and fluoropolymer coatings to control the hydrophobicity of paper surfaces, in parallel with improved gloss. Organic nanoparticles were synthesized and deposited from an aqueous dispersion. Due to the high glass transition temperature of the nanoparticles, the evaporation of water during curing leads to the formation of a roughness profile with microdomains (> 1 μm roughness) that are internally nanostructured (< 30 nm roughness). The hydrophobicity and gloss of this coating is controlled by a multilevel roughness profile in combination with fibrous substrates. As such, water contact angles of above 150° can be obtained while maintaining high gloss. Further analysis of the surface morphology for uncoated and nanoparticle coated papers is made by non-contact optical profilometry and AFM measurements. The overall scale-length of roughness measurements can be covered by calculating the correlation length from each surface profile. As such, the gloss values relate to a surface texture parameter determined by the ratio of root-mean-square roughness and correlation length on the microscale. The anisotropy in gloss corresponds to different roughness values in parallel and perpendicular directions. The water contact angles relate to the surface texture parameter on the nanoscale.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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028-041
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DOI:
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10.3183/NPPRJ-2013-28-01-p028-041
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Keywords:
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Coating, Gloss, Hydrophobicity, Roughness, Scaling, Styrene maleimide (SMI) nanoparticles
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Sample pretreatment for oxalate analysis and the effect of peroxide bleaching parameters on oxalate formation
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Matti Häärä, Jonas Konn, Anna Sundberg, and Stefan Willför
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Abstract:
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Calcium oxalate scaling can cause major problems in papermaking in connection to peroxide bleaching of mechanical pulps. Reliable oxalate analysis methods are needed for monitoring the oxalate balance in the process or for performance evaluation of a possible chemical anti-scale treatment. This is challenging due to the low solubility of calcium oxalate. In this study, the sample pretreatment and storage methods both for soluble and total oxalate analysis in mechanical pulp samples have been investigated. In addition, the effects of dissolved and colloidal substances in the dilution water, bleaching consistency, and replacement of NaOH with Mg(OH)2 as alkali source in alkaline peroxide bleaching of groundwood pulp were studied. All experiments were carried out on groundwood pulp of Norway Spruce (Picea abies). Suitable and simple pretreatment methods were established both for analysis of soluble oxalate and for the acidification of pulp samples prior to total oxalate analysis by ion chromatography. The results from the peroxide bleaching experiments showed that a higher concentration of dissolved and colloidal substances in the peroxide bleaching will result in increased oxalate formation. Replacing NaOH with Mg(OH)2 as the alkali source in peroxide bleaching to the same brightness level decreased the total amount of oxalate formed and increased its solubility. Increased bleaching consistency led to higher brightness gain and higher oxalate concentration in the filtrate, but the oxalate formation based on dry pulp was lower. The results indicate that Mg(OH)2-based peroxide bleaching at high consistency combined with good pulp washing would be a good way to minimize oxalate formation.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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042-050
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DOI:
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10.3183/NPPRJ-2013-28-01-p042-050
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Keywords:
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Analytical method, Bleaching consistency, Calcium oxalate, Magnesium hydroxide, Mechanical pulp, Oxalic acid, Peroxide bleaching, Sample pretreatment, Scale
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Brightness reduction of mechanical pulp in the wet end of a paper machine: The effect of pH, pulp washing and shear rate
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Pekka Varhimo, Jonas Konn, Marcus Lillandt and Jouni Paltakari
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Abstract:
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Brightness reduction of mechanical pulp in paper machine water circulations is a well-known phenomenon. However, the reasons behind the darkening are not fully known. The present paper is part of larger study aiming at finding out mechanisms and phenomena causing the brightness reduction of mechanical pulp and fillers in the wet end of a paper machine. The main focus of this paper is on the effect of pH, pulp washing and shear rate on the brightness reduction of mechanical pulp fines in the short circulation.
The effect of pH and pulp washing was studied in a device that simulates the short circulation of a paper machine. The brightness of the fines fraction was lower at higher pH (7.3 compared to 4.8) due to the lower light scattering of the fines whereas pH did not have a notable effect on the light absorption. The effect of pH on the optical properties of the fiber fraction was negligible in the tested pH range. Pulp washing clearly reduced the tendency to darkening of the fines and fiber fraction. This was probably due to light absorbing substances whose amount in the pulp suspension typically decreases during the washing.
The effect of shear rate was studied by agitating peroxide bleached TMP at 60°C using different agitation speeds. The increase in shear rate increased the rate of darkening. At the same shear rate levels, the rate of darkening was higher for the fines fraction than for the fiber fraction.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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051-058
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DOI:
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10.3183/NPPRJ-2013-28-01-p051-058
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Keywords:
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Brightness reduction, Dissolved and colloidal substances, Mechanical pulp, pH, Pulp washing, Shear, Thermomechanical pulp, Water circulation, Wet end
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Brightness reduction of calcium carbonate and calcium sulfate fillers in the wet end of a paper machine
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Pekka Varhimo, Jonas Konn, Marcus Lillandt and Jouni Paltakari
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Abstract:
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This study is part of a broader research aiming at finding out mechanisms and phenomena causing the brightness reduction of mechanical pulp and fillers in the wet end of a paper machine. The main focus of this study was on the darkening of precipitated calcium carbonate (PCC) and precipitated calcium sulfate (PCS) fillers circulating in the short circulation.
Brightness reduction of fillers was studied using a laboratory scale circulation device. Diluted TMP filtrate or deionized water was used as wire water in the circulations. Darkening of fillers in waters containing wood based dissolved and colloidal substances were assessed. Samples were taken during the circulation and optical properties of prepared sheets measured. In addition, the adsorption of wood based dissolved and colloidal substances on the fillers was studied using UV Raman spectrometry. The fillers were also circulated with the fines fraction of peroxide bleached TMP to study the brightness reduction of the fillers in the presence of fines.
Both PCC and PCS fillers adsorbed wood based dissolved and colloidal substances from the water phase resulting in decreased brightness. PCC filler was more prone to adsorb these substances and was therefore more susceptible towards darkening. At low pH, dissolution of PCC results in formation of carbon dioxide. This was found to be very detrimental to brightness.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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059-067
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DOI:
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10.3183/NPPRJ-2013-28-01-p059-067
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Keywords:
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Brightness reduction, Filler, PCC, PCS, UV Raman, Water circulation, Wet end
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Filler clay induced discolouration of bleached mechanical pulp
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Hanne Narvestad, Øyvind W. Gregersen and Kjell-Arve Kure
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Abstract:
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Today’s pulp and paper industry is highly exposed to cost reduction pressures. The bleaching chemical cost may constitute 50-70% of the total chemical costs in the production of magazine paper grades. Thus, it is important to avert process conditions which enhance discolouration and consecutive increase in the bleaching chemical consumption. In this study, the effect of different commercial kaolins (china clays) on discolouration of thermomechanical pulp was assessed. The purpose of the work was to acquire new knowledge about clay-induced discolouration of mechanical pulp in order to minimize discolouration of pulp in the production process of supercalendered magazine paper.
Results showed that commercial kaolins can reduce the ISO-brightness of mechanical pulp by up to seven points under papermaking conditions. Mill experiences demonstrated that this discolouration had a considerable effect on the bleaching chemical consumption in a supercalendered magazine paper mill. The total bleaching chemical cost increased by at least 50% due to clayinduced discolouration.
The clay-induced discolouration of mechanical pulp was ascribed to the accessible iron in kaolin. This study revealed that the degree of clay-induced discolouration varies considerably between different commercial kaolins. Results indicated that the bleaching sequence and the metal ion profile of the mechanical pulp influences the degree of iron- and clay-induced discolouration upon pulp storage. It is recommended that producers of paper consisting of mechanical pulp and kaolin make demands on the potential clay-induced discolouration properties of the clay. The clay-induced discolouration test method developed in this work can be used for an acceptance check.
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The concept of stickies exposure for paper recycling processes
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Patrick Huber, Thierry Delagoutte, and Sylvie Ossard
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Abstract:
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Fragments of converting adhesive films (namely stickies) are the cause of severe runability problems in paper recycling processes. These tacky particles are picked-up by the paper machine clothes, inducing their clogging, which is often at the origin of the break of the running paper web. To investigate stickies related problems, these particles are usually characterized by their concentration in the pulp. Industrial experience has shown that it is often difficult to relate the frequency of paper web breaks to the concentration of stickies in the pulp. In this work, we propose that paper machine runability issues are related to the amount of stickies that is effectively exposed at the surface of the sheet to the machine clothes, so that their concentration is not sufficient to describe the problem. A definition of the stickies exposure concept is proposed, through statistical geometry methods. The effect of stickies morphological parameters on their exposure is studied theoretically. Their orientation and distribution within the sheet thickness is found to be of importance as well. Hopefully, this new concept will help to better understand runability problems on paper machines using recycled raw material. Admittedly, stickies exposure only represents the geometrical aspect of stickies deposition problems. Hence, this approach is only the first step towards a more general description of the stickies related problems, which would take into account other parameters, such as adhesion and paper strength.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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082-093
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DOI:
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10.3183/NPPRJ-2013-28-01-p082-093
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Keywords:
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Distribution, Macrostickies, Papermaking, Pressure sensitive adhesives, Recycling, Simulation, Statistics, Stickies
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A physical model for liquid movement into a porous substrate under the action of a pressure pulse
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Abstract:
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The dynamic behavior of ink movement under nip-pressure of a printing press has been studied. The theoretical model employed originates from the Bosanquet model that was previously applied to situations of constant or zero external pressures. In the present work, we extend the model to a printing situation where a time-dependent nip pressure presents. The general solution of the model for a simple liquid has been worked out, as in most situations the ink’s continuous phase can be approached as a Newtonian fluid, e.g. mineral oil in offset and water in flexo etc. The general solution is of analytical form thanks to the possibility to expand the nip-pressure profile into a Fourier series. For illustrative purposes, simulations with three model profiles, one rectangular, one sinusoidal, and one joint sinusoidal, have been performed. It is found that the profile of the nip-pressure plays a dominant role in liquid transfer and setting.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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094-100
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DOI:
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10.3183/NPPRJ-2013-28-01-p094-100
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Keywords:
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Ink dynamics, Ink-transfer, Nip-pressure profile, Printing dynamics
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Accelerated and natural ageing of offset prints covered with different varnishes
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Branka Lajić, Igor Majnarić, and Ivana Bolanča Mirković
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Abstract:
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The aim of this work was to determine the dependence of the colour fading of offset prints on the ageing process, relative to prints overprinted with waterbased dispersion varnish and UV-cured varnish. Natural ageing (outdoor conditions and the exposure to sunlight filtered by glass windows) and accelerated ageing (moist heat and light xenon arc lamp) treatments were carried out. In order to determine colour fading, colour difference, 2D gamut values and characteristic cross sections L20, L50 and L80, as well as 3D gamut values were used.
The yellow colour showed the largest colour difference when offset prints were exposed to accelerated ageing by means of exposure to xenon light. Magenta followed yellow. No significant stability was achieved by varnishing the yellow print with water-based dispersion varnish and UV-cured varnish. This was also the case with magenta. An increase of the gamut occurred after one week’s exposure of prints coated with water-based dispersion varnish to moist heat ageing. In contrast, on exposure of prints coated with UV-cured varnish, a decrease of gamut appeared. On further exposure of prints covered with either kind of varnish a decrease of gamut was evident. Indoor exposure of varnished prints to sunlight through a glass window had a minor influence on the gamut volume change in comparison with the exposure of prints to outdoor conditions.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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101-110
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DOI:
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10.3183/NPPRJ-2013-28-01-p101-110
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Keywords:
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Ageing, Colour difference, Gamut, Offset, UV varnish, Water-based dispersion varnish
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Stability of ink-jet prints under influence of light
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Barbara Blaznik, Klementina Možina and Sabina Bračko
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Abstract:
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The aim of this study was to establish whether the use of the desktop ink-jet printing technology, which is more inexpensive and available, is convenient for the preparation of lightfast documents. The influence of the spectral composition of light on paper and print properties was studied, as well as the influence of optical brighteners in paper on fading and the possibility of using archival paper with 30% of postconsumer waste paper fibres for document preparation. The colour samples were printed on three different papers with two different printers, which differed in the ink-jet printing technology and the chemical structure of ink.
After determining the paper properties and the colorimetric properties of prints using standard methods, the samples were exposed to xenon light, which simulates daylight in open space and behind window glass. The exposure to xenon light took place under well controlled conditions (spectral composition of light, temperature, relative humidity, exposure time). Based on the spectrophotometric measurements, the colour changes of papers and prints were evaluated on the basis of the CIELAB equation.
The research showed that the shortwave radiation proved to be more destructive. The composition of ink and the content of optical brighteners in paper substantially contributed to the latter, as it turned out that the prints on paper which contained optical brightening agents and the prints made with dye-based inks are less stable.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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111-118
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DOI:
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10.3183/NPPRJ-2013-28-01-p111-118
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Keywords:
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Archival paper, Ink-jet, Light fastness, Optical brighteners, Permanent paper, Post-consumer waste, UV radiation
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Flow modelling in a low consistency disc refiner
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Grzegorz Kondora and Dariusz Asendrych
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Abstract:
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The paper deals with modelling of the low consistency (LC) refining, one of the crucial stages of papermaking. The process is carried out with the use of a refiner, equipped with the system of grooved stator and rotor discs, which passing by very closely to each other treat mechanically the fibres improving their bonding abilities.
The complexity of the process including 2-phase suspension character, flow unsteadiness, 3-dimensionality, complex geometry and non-Newtonian pulp behaviour makes it extremely difficult to control in terms of fibres properties as well as of power consumption.
In the paper the computational fluid dynamics (CFD) study of a flow in a LC refiner is presented. The model concerns the paper pulp as a single-phase continuum so the flow may be described by laminar unsteady N-S equations with an adequate fluid characteristic. Although no fibres are considered, the model is able to predict the flow pattern in satisfactory agreement with available experimental observations.
A series of simulations was conducted for varying disc filling geometrical parameters as well as pulp suspension characteristics, including its Newtonian/non-Newtonian character and fibre consistency. The results of the simulations allowed an insight into the flow structure in the LC refiner disc filling and showed how strongly pulp consistency (through abrupt viscosity changes) affects the intensity of secondary flows and internal pulp circulation.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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119-130
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DOI:
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10.3183/NPPRJ-2013-28-01-p119-130
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Keywords:
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CFD, Fibre suspension, Internal circulation, LC refining, Optimisation, Pulp rheology, Viscosity
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Non-destructive high resolution measurements of spatial filler content distribution in paper
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Håkan Hägglund, Ole Norberg, and Per Edström
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Abstract:
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In this work, a non-destructive method is presented that enables the measurement of filler content in paper with high spatial resolution. The method uses an X-ray fluorescence setup that enables high resolution measurements of calcium content in the paper, together with a beta radiography measurement method, to assess the local filler content in the paper. An image registration method is used to combine the two measurement maps, and a calibration polynomial is applied to the point-wise values in order to calculate the local filler content.
The measurement methods show good accuracy. The grammage and the calcium content can be measured at a spatial resolution of 0.1 mm x 0.1 mm but the resolution for the filler content map was in this work chosen to 1 mm x 1 mm in order to minimize image registration errors.
The method is illustrated using two paper samples, a laboratory paper and a commercial 80 g/m² copy paper. From the methods used in this work, a difference is shown between the two paper samples in how the filler content distribution is related to the paper formation.
With the help of image registration, point-wise measurements of filler content from both sides of the samples can be compared.
The method can be used together with other high resolution measurements in order to analyze the simultaneous interrelation between different paper properties. The high resolution measurements of filler content will be particularly valuable for the analysis of the underlying causes to optical variations in paper and print.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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131-136
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DOI:
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10.3183/NPPRJ-2013-28-01-p131-136
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Keywords:
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Filler content, Grammage, High resolution, Image registration, Paper properties, Point-wise, Spatial, Variations
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Web-wide imaging of paper; Analyzing the potential of on-line light transmittance measurement in quality control and diagnostics of paper
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Jukka-Pekka Raunio, Ville Tirronen, Ilkka Lehtoranta, Risto Ritala
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Abstract:
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The quality control at paper machine is based on the on-line scanning basis weight measurements. However, due to the scanning the uncertainty of a basis weight estimate is rather large and the representativeness rather poor. Therefore, the potential of the web inspection system (WIS) which measures the light transmittance of paper online was evaluated in quality control and diagnostics of paper. The target paper was measured with the on-line web inspection system, the on-line quality control system (QCS) scanner, and the off-line web-analyzer. The CD profiles of each measurement were analyzed and it was noticed that the correlation between the on-line light transmittance and the basis weight measurements was rather low. Furthermore, it was observed that the inaccurate time alignment between the measurement systems (CD profiles are not stable in time) and the illumination variations in the WIS images were the major reason for low correlation. With reference images most of the variation in illumination can be removed. The analysis method presented in this work can be applied to evaluate the quality of the WIS images in the basis weight estimation and to evaluate the need for reference images.
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Testing an activity-based costing model with a virtual paper mill
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Heikki Korpunen and Jouni Paltakari
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Abstract:
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The paper industry has a strong foothold in the Finnish national economy. Paper mills are one of the key targets for wood procurement companies, and the wood paying capability of a mill is one key factor in determining wood raw material flows. We studied the cost structure of a virtual paper mill, which produces 300,000 air-dry metric tonnes of supercalendered magazine paper annually. We used the activity-based costing (ABC) method for cost modelling and analysis. Paper production was divided into ten sub-processes: receive, unload and debarking; TMP mill; stock preparation; headbox and former; press section; dryer section; reeler; calender; winder; and roll storage. The total annual production cost was 88.3 million euros. The TMP mill and dryer processes incurred most of the production costs, approximately 34% and 18% respectively. The main source of fibre was Norway spruce, and we tested two cases where the fibre was procured from clear cuttings and thinnings. Our study indicates that the prices of paper and energy but also basic densities of wood and bark and bark percentage of wood can have an effect on the net profits of the paper mill. When the Norway spruce was procured from clear cuttings, the mill level annual net profit was 31.3 million euros, which was 13.3% higher than when the wood came from thinnings. Generally, our results proved that the ABC is a pragmatic cost calculation method and with the parameters used, it was estimated that papermaking can still be profitable in Nordic conditions.
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Issue:
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Volume 28, 2013, Issue No. 1
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Pages:
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146-155
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DOI:
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10.3183/NPPRJ-2013-28-01-p146-155
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Keywords:
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Activity-based costing, Paper mill, Profitability, Wood properties
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Mild steam explosion: A way to activate wood for enzymatic treatment, chemical pulping and biorefinery processes
Kerstin Jedvert, Yan Wang, Anna Saltberg, Gunnar Henriksson, Mikael E. Lindström and Hans Theliander
2012-27-05-p828-835-Jedvert.pdf
Nanocellulose characterization with mechanical fractionation
Atsushi Tanaka, Veli Seppänen, Juha Houni, Asko Sneck and Pentti Pirkonen
2012-27-04-p689-694-Tanaka.pdf
Topo-chemical modification of fibres by grafting of carboxymethyl cellulose in pilot scale
Mikael Ankerfors, Elisabeth Duker and Tom Lindström
2013-28-01-p006-014-Ankerfors.pdf
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Studies on topochemical modification of cellulosic fibres Part 1. Chemical conditions for the attachment of carboxymethyl cellulose onto fibres
Janne Laine, Tom Lindström, Gunborg Glad Nordmark and Gunnel Risinger
Volume: 15 Issue: 5 Pages: 520-526 Published: 2000
Polyelectrolyte adsorption onto cellulose fibres - A review
Lars Wågberg
Volume: 15 Issue: 5 Pages: 586-597 Published: 2000
On the structural significance of the kappa number measurement
Göran Gellerstedt and Jiebing Li
Volume: 13 Issue: 2 Pages: 153-158 Published: 1998
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home » tables of contents » volume 09, 1994 » issue no. 4
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Nordic Pulp and Paper Research Journal was started by SPCI (the Swedish Association of Pulp and Paper Engineers) and SPCI has been managing NPPRJ until end of 2012. From 2013, NPPRJ is owned by Mittuniversitetet (Mid Sweden University). The Home Page and its functions are managed by Foritec AB on behalf of Mittuniversitetet.
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