Change search
Refine search result
89101112 501 - 550 of 552
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 501.
    Valdebenito, Fabiola
    et al.
    Center for Advanced Polymers Research, Chile; La Frontera University, Chile.
    Pereira, Miguel
    University of Concepcion, Chile.
    Ciudad, Gustavo
    La Frontera University, Chile.
    Azocar, Laura
    La Frontera University, Chile.
    Briones, Rodrigo
    Center for Advanced Polymers Research, Chile.
    Chinga-Carrasco, Gary
    RISE - Research Institutes of Sweden, Bioeconomy, PFI. La Frontera University, Chile.
    On the nanofibrillation of corn husks and oat hulls fibres2017In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 95, p. 528-534Article in journal (Refereed)
    Abstract [en]

    Cellulose nanofibrils (CNF) were isolated from agro-industrial waste (corn husks and oat hulls) and market kraft pulp fibres, and a detailed comparative study was performed. Initially, the raw materials were subjected to a conventional pulping process to remove lignin and hemicelluloses. The chemical pre-treatment was based on 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO)-mediated oxidation and the mechanical treatment was carried out with a high-pressure homogenizer. An extensive characterization of the raw material and of the nanofibrillated celluloses was performed, considering structural and chemical aspects. CNF films were produced for their characterization by optical methods, laser profilometry (LP), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Considering the same pulping and chemical pre-treatment, the analyses indicated that the oxidized corn husks fibres had higher carboxylate content and thus a larger tendency to nanofibrillate compared to the oat hulls fibres. The obtained content of carboxylic acids was directly proportional to the content of cellulose in the assessed samples, confirming the selectivity of the TEMPO-mediated oxidation. The fibrillated corn husks material had a minor fraction of residual fibres (<4%) and homogeneous nanofibril width distribution (<20 nm), which is a major achievement. The homogeneous CNF morphology was confirmed by AFM analysis. Hence, this study demonstrates that the assessed agro-industrial wastes are sustainable resources for production of CNF, which may have a wide range of value-added applications.

  • 502. Varhimo, A
    et al.
    Hoffstedt, Christian
    RISE, Innventia.
    Samuelsson, Åsa
    RISE, Innventia.
    Helin, T
    Suurnakki, A
    Extraction of xylan from bleached hardwood kraft pulp2014Conference paper (Refereed)
  • 503.
    Veguta, Vijaya Lakshmi
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy. RISE, Innventia. KTH Royal institute of technology, Sweden.
    Stevanic, Jasna S.
    RISE - Research Institutes of Sweden, Bioeconomy. RISE, Innventia.
    Lindström, Mikael E.
    KTH Royal institute of technology, Sweden.
    Salmen, Lennart
    RISE - Research Institutes of Sweden, Bioeconomy. RISE, Innventia.
    Thermal and alkali stability of sodium dithionite studied using ATR-FTIR spectroscopy2017In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 12, no 2, p. 2496-2506Article in journal (Refereed)
    Abstract [en]

    Sodium dithionite (Na2S2O4) may have the potential to be used as a reducing agent for the stabilization of glucomannan in kraft cooking for increased pulp yield. However, due to the fact that dithionite decomposes under the conditions of kraft pulping, studies of the effects of dithionite in kraft pulping are non-conclusive; sometimes clearly showing an increased yield, and in other studies no effect at all. The specific conditions influencing dithionite degradation are also unclear. For that reason, this study was conducted to determine the thermal and chemical stability of sodium dithionite with respect to specific factors, such as the pH, temperature, heating time, and the concentration of sodium dithionite solution. The study was performed under anaerobic conditions using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The thermal and alkali stability of the sodium dithionite solution was shown to decrease with increasing temperature, heating time, and concentration of the solution at the alkaline conditions studied. The thermal stability decreased rapidly at weak alkalinity (pH 9) as well as in high alkalinity (pH 14), whereas the sodium dithionite was rather stable at moderate alkalinity (pH 11.5 to pH 13).

  • 504.
    Viforr, Silvia
    et al.
    RISE, STFI-Packforsk.
    Salmen, Lennart
    RISE, STFI-Packforsk.
    Shear/compression of chips for lower energy consumption in TMP refining2008In: Appita journal, ISSN 1038-6807, Vol. 61, no 1, p. 49-55Article in journal (Refereed)
    Abstract [en]

    Fundamental studies of the deformation behaviour of wood show that combining small amounts of shear along with compression within a roll press reduces the work required for cell wall deformation. This permanent deformation can be increased by: increased number of passes through the nip reduced roll speed increased process temperature. Refining trials showed that the strength properties (except for the tear index), as well as the optical properties of TMP produced from these shear/compression pretreated chips are improved, with the potential of reducing electric energy by approx. 100 kWh/tonne, when compared to untreated chips.

  • 505.
    Vomhoff, H.
    et al.
    RISE, Innventia.
    Gabrielsson, A.
    RISE, Innventia.
    Tysen, A.
    RISE, Innventia.
    Investigations into dynamic liquid absorption properties of kitchen towel2014Conference paper (Refereed)
  • 506.
    Vomhoff, Hannes
    et al.
    RISE, Innventia.
    Farahani, Farnaz
    RISE, Innventia.
    Innventia Compression Test (ICT): a method to measure compressibility of tissue products2016In: Tissue World New Orleans 2016, 2016Conference paper (Other academic)
    Abstract [en]

    The out-of-plane compressibility of kitchen towels is a very important product property in order to achieve a high absorption capacity. A method for the measurement of the compressibility was therefore developed. It allows the compression of a tissue sample by a defined pressure between 0 and 30 kPa. The thickness of the sample is measured. Both single-ply base paper samples and fully converted multi-ply products can be evaluated. The measurement can be performed on both dry or wet samples. Multiple compressions of the samples can also be performed in order to evaluate the difference in plastic deformation as a result of consecutive compressions. Under normal conditions, the applied pressure is gradually increased from 0 to 30 kPa and then decreased back to 0 kPa. This procedure can then be repeated. The compressibility of the sample was evaluated in terms of a bulk versus applied pressure relationship. In the presentation, the method will be explained and the compressibility of different kitchen towel products will be presented and discussed. Using some example of results, the effect of sheet structure, multiple compressions and wetting of the samples and will be illustrated.

  • 507.
    Vomhoff, Hannes
    et al.
    RISE, Innventia.
    Farahani, Farnaz
    RISE, Innventia.
    Bouveng, Mikael
    RISE, Innventia.
    Östlund, Catherine
    RISE, Innventia.
    Evaluation of the compressibility of kitchen towel2016In: Tappi Tissue 360 Forum, 2016Conference paper (Other academic)
    Abstract [en]

    The out-of-plane compressibility of kitchen towels is a very important product property in order to achieve a high absorption capacity. A method for the measurement of the compressibility was therefore developed. It allows the compression of a tissue sample by a defined pressure in the range between 0 and 30 kPa. The thickness of the sample is measured. Both single-ply base paper samples and fully converted multi-ply products can be evaluated. The measurement can be performed on both dry or wet samples. Multiple compressions of the samples can also be performed in order to evaluate the difference in plastic deformation as a result of consecutive compressions. Under normal conditions, the applied pressure is gradually increased from 0 to 30 kPa and then decreased back to 0 kPa. This procedure can then be repeated. The compressibility of the sample was evaluated in terms of a bulk versus applied pressure.The compressibility of different tissue grades was evaluated and compared. A clear difference in compressibility between standard DCT and structured tissue samples was observed. The first compression cycle lead to a considerable irreversible, plastic deformation of the sample. The plastic deformation decreased then considerably during the consecutive compression cycles. Wetting the samples lead to a considerable decrease in compressibility. The results allow interesting conclusions in terms of the influence of base sheet production process and the converting processes on the absorption properties.

  • 508.
    von Schenck, A.
    et al.
    RISE, Innventia.
    Berglin, N.
    RISE, Innventia.
    Uusitalo, J.
    Ethanol from Nordic wood raw material by simplified alkaline soda cooking pre-treatment2013In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, p. 229-240Article in journal (Refereed)
  • 509. Vähä-Savo, N.
    et al.
    Demartini, N.
    Ziesig, R.
    RISE, Innventia.
    Tomani, P.
    RISE, Innventia.
    Theliander, H.
    Valimaki, E.
    Hupa, M.
    Combustion properties of reduced-lignin black liquors2014In: TAPPI Journal, ISSN 0734-1415, Vol. 13, no 8, p. 81-90Article in journal (Refereed)
  • 510.
    Vähä-Savo, Niklas
    et al.
    Åbo Akademi University, Finland.
    Demartini, Nikolai
    Åbo Akademi University, Finland.
    Ziesig, Rufus
    RISE, Innventia.
    Tomani, Per
    RISE, Innventia.
    Theliander, Hans
    Chalmers University of Technology, Sweden.
    Välimäki, Erkki
    Valmet Power Oy, Finland.
    Hupa, Mikko
    Åbo Akademi University, Finland.
    Combustion properties of reduced lignin black liquors2014Conference paper (Refereed)
    Abstract [en]

    The growing interest in production of green chemicals and biofuels from biomass provides an incentive for pulp mills to identify new possibilities in recovering more wood components from the pulping process. One possibility is to use lignin, separated from black liquor. We undertook this work to determine the combustion properties of reduced-lignin black liquors-two kraft liquorsand one soda liquor-in a laboratory-scale, single-particle furnace. The combustion times, maximum swollen volume, nitric oxide formation, cyanate formation, and sulfur release were measured for the original liquors, the filtrates, and intermediate levels of lignin reduction. Combustion experiments were conducted at 900°C in 10% oxygen. Cyanate formation experiments were carried out by pyrolyzing the droplets at 800°C in 100% nitrogen to form a char. The chars were then gasified at 800°C in a 13% carbon dioxide/87% nitrogen atmosphere to obtain the smelt. Sulfur release was studied by pyrolyzing the samples at temperatures ranging from 300°C to 900°C. Liquors with the lowest lignin content had a smaller maximum swollen volume than the original sample. The devolatilization time was not affected by the lignin removal to any great extent, but lignin removal did have a clear effect on the char burning time. The amount of formed nitric oxide (g N/kg black liquor solids) remained constant or decreased slightly with increasing lignin removal in the kraft liquor samples, while for the soda samples the amount of nitric oxide formed increased. The amount of cyanate decreased clearly when comparing the samples with lowest lignin content to the original liquor samples. The peak sulfur release occurred at 500°C for both kraft liquors. In almost all experiments, the share of sulfur released was highest for the original samples and lowest for the sample with lowest lignin content. These results provide new data on combustion properties for reduced-lignin black liquors and indicate that for lignin removal levels up to about 20%, no significant changes are expected in the combustion behavior. Application: This work will help mills identify the effect of lignin precipitation on combustion properties of black liquor.

  • 511. Vähä-Savo, Niklas
    et al.
    Demartini, Nikolai
    Ziesig, Rufus
    RISE, Innventia.
    Tomani, Per
    RISE, Innventia.
    Theliander, Hans
    RISE, Innventia.
    Välimäki, Erkki
    Hupa, Mikko
    Combustion properties of reduced-lignin black liquors2014In: TAPPI Journal, ISSN 0734-1415, Vol. 13, no 8, p. 81-90Article in journal (Refereed)
  • 512.
    Wadsborn, R.
    et al.
    RISE, Innventia.
    Samuelsson, A.
    RISE, Innventia.
    Berglin, N.
    RISE, Innventia.
    Bialik, M.
    RISE, Innventia.
    Karlholm, I.
    RISE, Innventia.
    Pulp mill management of non-process elements aided by process simulation2011Conference paper (Refereed)
  • 513.
    Wallbäcks, Lars
    et al.
    RISE, Innventia.
    Theliander, Hans
    RISE, Innventia.
    Johanzon, O
    Johansson, Jan-Åke
    RISE, Innventia.
    Pettersson, Tommy
    Welin, Anna
    Stable lime kiln feed through on-line measurements and feed control2014Conference paper (Refereed)
  • 514.
    Wallinder, Johan
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy, Biorefinery and Energy.
    Lindgren, Karin
    RISE - Research Institutes of Sweden, Bioeconomy, Biorefinery and Energy.
    Samuelsson, Åsa
    RISE - Research Institutes of Sweden, Bioeconomy, Biorefinery and Energy.
    Dynamic modelling of a kraft pulp mill producing softwood and hardwood pulp in campaigns2018In: Pulping Engineering and Environmental Recycling Sustainability Conference, PEERS 2018: Technical Solutions for Today and Beyond, 2018, p. 673-683Conference paper (Refereed)
    Abstract [en]

    Pulp mills producing hardwood and softwood pulp in campaigns have constantly changing process stream compositions. There is aneed to know how these variations develop during the campaigns and that was the objective of this study. A dynamic model, built in the simulation program WinGEMS, has been created by including tanks and reactors with known residence times. A case with a mill producing softwood and hardwood pulp in campaigns has been designed and studied. Some of the studied parameters were white liquor concentration, recovery boiler load and composition of weak black liquor. The dynamic changes of these parameters were not unexpected; however, the time responses and magnitude of these changes were of bigger interest. For instance, it took a little more than 3 days, from the start of a new campaign, to totally replace the weak black liquor from one wood species with the other. In order to interpret results successfully, it was necessary to be aware of the residence time between certain positions in the pulp mill model.

  • 515. Wallmo, H.
    et al.
    Theliander, H.
    Jönsson, A. -S
    Wallberg, O.
    Lindgren, Karin
    RISE, STFI-Packforsk.
    Lignin from hardwood black liquor: A combination of membrane filtration and LignoBoost technique for improved process capacity and lignin quality2008In: 2008 Nordic Wood Biorefinery Conference - Proceedings: NWBC 2008, 2008, p. 240-241Conference paper (Refereed)
  • 516.
    Wang, Miao
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy.
    Li, Jiebing
    RISE - Research Institutes of Sweden, Bioeconomy.
    Demethylation and other modifications of industrial softwood kraft lignin by different laccase-mediator systems2017In: The 7th Nordic Wood Biorefinery Conference held in Stockholm, Sweden, 28-30 Mar. 2017: NWBC 2017, Stockholm: RISE Bioekonomi , 2017, p. 242-243Conference paper (Refereed)
    Abstract [en]

    An industrial softwood kraft lignin was treated by different laccase-mediator systems (LMS) followed by comprehensive structural analysis. Analysis revealed that demethylation was a common reaction for all the LMS combinations investigated. After reaction, methanol was always released into the solutions. A reduction in the methoxyl content of the lignins was observed in the obtained products. The treatment reduced the quantities of different types of phenolic aromatic rings, with G units being the most attacked structures. Decarboxylation was also detected in two of the LMS, namely L1-TEMPO andL2-HBT. The highest demethylation rate came from the L1-ABTS combination and the most severe overall structural modification. Lignin polymerisation was observed for all treatments, with the L1-ABTS combination demonstrating the highest Mp, Ma and Mw values. An increased polydispersity was also observed for all the treatments, with the highest increase in polydispersity found for the L1-ABTS treatment. In addition, lignin depolymerisation took place. It has been concluded that the most efficient demethylation was achieved by N51002-ABTS.

  • 517.
    Wang, Miao
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy. RISE, Innventia. KTH Royal Institute of Technology, Sweden.
    Sjöholm, Elisabeth
    RISE - Research Institutes of Sweden, Bioeconomy. RISE, Innventia.
    Li, Jiebing
    RISE - Research Institutes of Sweden, Bioeconomy. RISE, Innventia. KTH Royal Institute of Technology, Sweden.
    Fast and reliable quantification of lignin reactivity via reaction with dimethylamine and formaldehyde (Mannich reaction)2017In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 71, no 1, p. 27-34Article in journal (Refereed)
    Abstract [en]

    The influence of pH on the Mannich reaction (amino alkylation in the presence of formaldehyde) has been analyzed by liquid chromatography-mass spectrometry (LC-MS) with vanillin (VA) as a model compound and a purified softwood kraft lignin (SKL) as a substrate. The reaction products of VA were studied at pH 5, 7, and 9 at 60°C for 4 h. The Mannich adduct and side reaction products with methylene bridge were found at both pH 7 and 9, while only di-substituted by-products were observed at pH 5. Nitrogen contents determined from blank runs were substantial at pH 5 and negligible at pH 7. In VA or SKL, the resulting N-contents at pH 7 corresponded to a 76 or 62 mol% of the theory, respectively, i.e. based on the available C5 positions in phenolic guaiacyl units (G-units). In the case of SKL, 31P-NMR analysis confirmed a 77% conversion of all phenolic G-units into their C5 substituted derivatives. The Mannich reaction should be performed on lignin at pH 7 for 1 h to suppress unwanted side reactions, which could be observed by LC-MS under other pH conditions. The reaction is suitable for fast and reliable determination of reactive C5-positions in lignin by multiplication of the N-content of the reaction products with a factor of 1.6.

  • 518.
    Wernersson Brodin, F.
    et al.
    RISE, Innventia, PFI – Paper and Fiber Research Institute.
    Weiby Gregersen, Ø
    NTNU Norwegian University of Science and Technology, Norway.
    Syverud, Kristin
    RISE, Innventia, PFI – Paper and Fiber Research Institute.
    Cellulose nanofibrils: Challenges and possibilities as a paper additive or coating material – A review2014In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 1, no 29, p. 156-166Article in journal (Refereed)
  • 519.
    Wiberg, Anna
    et al.
    RISE, Innventia.
    Söderberg, Daniel
    KTH Royal Institute of Technology, Sweden.
    Bjärestrand, Annika
    RISE, Innventia.
    Grussenmeyer, Heiner
    Stora Enso, Germany.
    Development of a future manufacturing concept for papermaking2015In: Paper Conference and Trade Show (PaperCon 2015), TAPPI Press, 2015, Vol. 2, p. 786-795Conference paper (Refereed)
    Abstract [en]

    Resource efficiency is one of the keys to future papermaking. This paper present a project where a top-down approach has been applied in order to identify, evaluate and combine a set of technologies for application on an existing paper machine. The project was performed within the BoostEff EU project, which had the general goal of qualifying stratified forming in combination with advanced fiber selection and modification.The starting point for the research and development work was a specific chosen paper machine at a Stora Enso paper mill, and the process that was developed was called the Future Manufacturing Concept (FMCs) for manufacturing of high-quality Super Calandered (SC) paper.The specific objective of the project was to develop a concept for SC-Paper production that would give lower environmentalimpact as well as reduced production costs. The project considered stock-preparation and the paper machine forming section. The research and development was made in pilot-scale as well as in mill-scale.Apart from being a specific result for the mill the technologies can be used more generally and the project approach would be of good use for other production units. It should also be noted that all technologies that used in the Future Manufacturing Concept are available on the market today.

  • 520.
    Wickholm, Kristina
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy.
    Williams, Helen
    Karlstad University, Sweden.
    Lindström, Annika
    RISE - Research Institutes of Sweden, Bioeconomy. RISE, Innventia.
    Lorentzon, Ann
    RISE - Research Institutes of Sweden, Bioeconomy. RISE, Innventia.
    Wikström, Fredrik
    Karlstad University, Sweden.
    Innovative packaging for reduction of food waste from producer to consumer2016In: IAPRI 2016 - 20th World Conference on Packaging: Innovation, Development and Sustainability in Packaging, 2016Conference paper (Other academic)
    Abstract [en]

    Increasing population and environmental changes poses a significant pressure on the global food supply chain. With the large quantities of food waste that’s been reported over the past couple of years packaging can play a more significant role in reducing the food wastage. Together with actors along the entire value chain we are developing new innovative packaging solutions to reduce food waste throughout the value chain, from food producers to consumers. The purpose of the study is to design and optimize new packaging system solutions so that no part of the chain is optimized at the expense of any other part. In the fall of 2015 the food wastage was examined in three supply chains, salsa in glass jar (A), rice pudding in plastic packaging (B) and lettuce in plastic packaging (C), by using waste audits in the businesses, collecting, comparing and analyzing data. For consumer insights ethnographic studies was used in ten Swedish households. Interviews have also been conducted with consumers in retail stores. The supply chain study indicates little wastage for A and B and higher for C. Consumer report some handling difficulties with the food packaging and reasons why food is wasted. The main reasons being that the food gets bad, difficulties to empty the packaging and that the amount of food is higher than their needs. A majority of the consumer state that they often view packaging as something unnecessary. Consumers do not give packaging functions many thoughts in general and many have difficulties in judging the packaging functions.

  • 521. Wittberg, L.P.
    et al.
    Björkman, M.
    Khokhar, G.
    Mohlin, U.-B.
    RISE, Innventia.
    Dahlkild, A.
    Flow conditions in the grooves of a Low-Consistency refiner2012In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, no 2, p. 173-183Article in journal (Refereed)
  • 522.
    Wolf, Jens
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy.
    Ahlroth, Mikael
    RISE - Research Institutes of Sweden, Bioeconomy.
    Anheden, Marie
    RISE - Research Institutes of Sweden, Bioeconomy.
    Wadsborn, Rikard
    Stora Enso, Sweden.
    Eriksson, Johan
    Stora Enso, Sweden.
    Model-based performance monitoring in a recovery boiler: proof of concept2017In: International chemical recovery conference, May 24-26, 2017, Halifax, Canada, 2017Conference paper (Refereed)
    Abstract [en]

    The concept of model-based performance monitoring has been tested in a recovery boiler operating in a Swedish kraft pulp mill. Key performance indicators (KPI) have been calculated and used to visualise the degree of fouling of boiler bank, super heaters and economiser of the recovery boiler. The KPIs illustrate the actual degree of fouling independently from the actual thermal load. The presented tool enables an early warning for massive fouling in the boiler. Even smaller changes in boiler performance can be followed enabling operation close to maximum capacity. The tool may also support operators to test modifications of the operation, for instance. A trend for the sticky temperature of dust particles has been added as a first approach to provide a measure for a critical flue gas temperature. That trend in combination with an indirectly measured flue gas temperature adds further value to model-based performance monitoring.

  • 523.
    Wolf, Jens
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy.
    Bialik, Marta
    RISE - Research Institutes of Sweden, Bioeconomy.
    Jensen, Anna
    RISE - Research Institutes of Sweden, Bioeconomy.
    Modelling of precipitation of silicon, aluminium and phosphorus into green liquor dregs2017In: International chemical recovery conference, May 24-26, 2017, Halifax, Canada, 2017Conference paper (Refereed)
    Abstract [en]

    A set of empirical equations is presented for modelling the precipitation of aluminium, silicon and phosphorous in green liquor plants as a function of initial concentrations of these elements plus magnesium, calcium and alkali in the dissolver. As process parameters, the model includes residence time and temperature. Concentrations, temperature and residence time have been varied according to a factor design plan. Main findings are that in laboratory experiments it was possible to remove aluminium, silicon and phosphorous down to concentrations below their solubility in white liquor thus avoiding accumulation of these elements in the lime cycle. In addition, the experimental work showed that the initial concentrations of aluminium, silicon and phosphorous in raw green liquor have a strong increasing impact on their concentrations in filtered green liquor.

  • 524.
    Wågberg, Pia
    et al.
    RISE, Innventia.
    Ritzen, Sofia
    Forest sector transition from process to product innovation: critical events in cases of collaboration between established and new firms2013Conference paper (Refereed)
  • 525.
    Xin, Zhiqing
    et al.
    BIGC Beijing Institute of Graphic Communication, China.
    Liu, Jianghao
    BIGC Beijing Institute of Graphic Communication, China.
    Gu, Lingya
    BIGC Beijing Institute of Graphic Communication, China.
    Fang, Yi
    BIGC Beijing Institute of Graphic Communication, China.
    Mo, Lixin
    BIGC Beijing Institute of Graphic Communication, China.
    Yang, Li
    RISE - Research Institutes of Sweden, Bioeconomy, Papermaking and Packaging.
    Surface energy guided patterning for printed electronics applications2018In: 45th International IARIGAI conference, 2018Conference paper (Other academic)
    Abstract [en]

    We demonstrated patterning method for silver nanoparticle ink by wire-wound rod coating on commercial paper substrate. The hydrophobic and hydrophilic zones (patterns) on the paper surface were created by combining coating of hydrophobic dispersion with selective plasma treatment using a mask. Thanks to the surface energy difference in different zones, the silver nanoparticle ink self-aligned to form desired patterns, e.g. a matrix of lines of 0.5 mm wide with 0.3 mm spacing.

  • 526.
    Yang, L.
    RISE, Innventia.
    Improved methods for adjusting the uv content of measurement instrument illumination for papermaking industry2014In: Proceedings of SPIE - The International Society for Optical Engineering, 2014Conference paper (Refereed)
  • 527.
    Yang, Li
    RISE - Research Institutes of Sweden, Bioeconomy, Papermaking and Packaging.
    Detailed analysis of the UV-adjustment techniques used in paper and graphic industries2017In: Color Research and Application, ISSN 0361-2317, E-ISSN 1520-6378, Vol. 42, no 1, p. 19-26Article in journal (Refereed)
    Abstract [en]

    Many commercial materials (papers and boards) contain optical brightening agents also known as fluorescent whitening agents. Adequate adjustment of the UV content of a measurement device (e.g., spectrophotometers) is essential for accurate color measurement. As specified in the ISO standards, the UV content is adjusted against an assigned value of an international reference transfer standard, for example, CIE whiteness (D65/10°) for the CIE illuminant D65 or ISO brightness for the C illuminant. Because of the simplicity, these approaches have gained great popularity in papermaking industry. Yet, there has been little evidence indicating how accurate the total spectral radiance factor corresponding to the single assigned value is reproduced. Hence, we present a method that quantitatively evaluates the accuracy of the UV-adjustment technique, through comparing the total spectral radiance factors obtained from UV adjustment with the assigned ones. This method has been applied to three second-level international reference transfer standard illuminated by three standard illuminants, D65, C, and D50. We found that the major differences between the assigned spectra and those obtained from the UV adjustments occur in the blue band where fluorescence is strong. At a few wavelengths, the differences may be up to 4-5%. Nevertheless, their color differences corresponding to the assigned spectra and those obtained from the UV adjustments are still smaller than unity (1 ΔE*) for all of the illumination conditions. Two instruments using the representative UV adjusting techniques, for example, the conventional UV-adjusting with an adjustable (GG395) UV filter and the numerical UV-filtering, have been studied.

  • 528.
    Yang, Li
    RISE, Innventia.
    Ink dynamics and ink transfer under printing nip2012Conference paper (Refereed)
  • 529.
    Yang, Li
    RISE, Innventia.
    Kubelka Munk model in paper optics: successes, limitations and improvements2011In: / [ed] Hirn, U., 2011, , p. 3Conference paper (Refereed)
  • 530.
    Yang, Li
    RISE, Innventia.
    Optical measurements of paper and textile: Influences from the instrumental setups and the structural and surface characteristics2015In: 9th International paper and coating chemistry symposium, Tokyo, Japan, Oct 29, 2015Conference paper (Other academic)
    Abstract [en]

    Spectral reflectance, radiance factors, gloss etc of paper and textile are often regarded as intrinsic properties of the materials alone. But in practice, instrumental readings of these properties depend even on the instruments setups, for instance, illumination/detection geometries, UV contents of the illumination, measurement areas etc. Comparative studies with four commercial spectrophotometers of three illumination/detection geometries, Diffuse/0-deg, Diffuse/8-deg and 45-deg/0-deg, have been conducted. These geometries are used in paper, textile and graphic industries, respectively. The materials analysed in this study include white and colour papers and textiles. The white papers contain fluorescent whitening agents (FWAs) whose excitation energies are only in UV wavelength bands. On the contrary, the colour papers have fluorescent agents whose excitation energies are in the visible wavelength bands, according to our measurements. Textile reference standards of different whiteness values are also included in order to study the influences from surface texture. The study confirms the strong influences of instruments setups, e.g. illumination/detection geometries, UV contents of the light sources etc, on the measured results. The study also reveals the significant influences from the combination of instrumental setups with the structural and surface characteristics of the measured samples.

  • 531.
    Yang, Li
    RISE, Innventia.
    Progress in intelligent packaging materials and technology2016Conference paper (Other academic)
  • 532.
    Yang, Li
    et al.
    RISE, Innventia.
    Christiansson, Hans
    Spatially resolved analysis of print through and ink penetration of printed matters2015Conference paper (Other academic)
    Abstract [en]

    Print through is an often encountered defect of printed maters, especially on paper grades of low and medium grammages. Print through phenomena have two contributing components, show through and strike through, resulting from insufficient paper opacity and ink penetration, respectively. The existing measurement method of print through and its components are calculated from a set of spectral reflectance values of printed and non-printed paper samples. These reflectance values are from rather big areas that equal to the opening of the employed spectrophotometer (say 33 mm in diameter). Thus, the calculated print through, show through and strike through, are only average values of the measured areas. This method has intrinsic weaknesses as paper is an inhomogeneous medium whose structure and materials compositions vary from one position to another, leading to inhomogeneous show through and strike through (opacity and ink penetration) across the measured areas, especially for papers of low and medium grammages.In this report we present a new method that enables one to take into account of variations in print through across the measured areas. The method employs a scanner that scans the printed and unprinted samples into RGB images of desired spatial resolutions. With the help of calibration patches that are simultaneously scanned as the measured samples, the RGB image signals can be converted into reflectance values. These reflectance values are then used to compute the print through, show through and strike through. Moreover, by means of Kubelka-Munk model, the depth of ink penetration at each spatial position can also be obtained. The developed method has been implemented in Matlab and successfully been applied to printed samples of newsprint and office papers. Comparative studies between instrumental measurements and perceptual evaluations confirm that the print through variations across the printed areas have strong influences on the print quality assessments. It is also found that using internal size agents in paper making is helpful for reducing ink-penetration.

  • 533.
    Yang, Li
    et al.
    RISE, Innventia.
    Hedberg, Viktoria
    Hagberg, Anni
    RISE, Innventia.
    Surface sizing for hybrid printing2012Conference paper (Refereed)
  • 534.
    Yang, Li
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy.
    Liu, J
    Beijing Institute of Graphic Communication, China.
    Wei, X
    Beijing Institute of Graphic Communication, China.
    A model of inkjet printing on porous substrates incorporating droplet impact2017In: 44th International Research Conference of iarigai: Proceedings / [ed] Gane P, Darmstadt: International Association of Research Organizations for the Information, Media and Graphic Arts Industrie (IARIGAI), 2017, Vol. 44, p. 3-6Conference paper (Refereed)
    Abstract [en]

    A model of inkjet printing dynamics has been developed that enables a comprehensive view to be obtained of the relationships between the characteristics of the ink droplet (volume, striking speed, viscosity and surface tension), substrate properties and interactions between the ink and the substrate. Simulations based on the three equations that are the major results of the model have provided an understanding of the basics of inkjet printing. Pressure profiles resulting from ink-striking by ink droplets of different volumes and jetting speeds have been obtained. The time duration of the striking process was in the order of microsecond and the peaks of the striking pressure were solely dependent on the jetting velocities, while the duration time of the striking processes was dependent only on the droplets volumes. The penetration length (depth) was heavily dependent on the contact angle. For a coated surface of small pores, the initial penetration depth was 0.26 micron when the striking speed was 30m/s. For a larger pore, the corresponding depth was 1.30 micron.

  • 535.
    Yang, Li
    et al.
    RISE, Innventia.
    Liu, Jianghao
    Gu, Lingya
    Detailed insights to liquid absorption and liquid-paper interaction2013Conference paper (Refereed)
  • 536.
    Yang, Li
    et al.
    RISE, Innventia.
    Thorman, Sofia
    RISE, Innventia.
    Teleman, Anita
    RISE, Innventia.
    Flexographic printability of packaging: challenges and new approaches2014Conference paper (Refereed)
  • 537.
    Yang, Li
    et al.
    RISE, Innventia.
    Thorman, Sofia
    RISE, Innventia.
    Teleman, Anita
    RISE, Innventia.
    Study on flexpgraphic printability of packaging2014In: China Printing and Packaging Study, ISSN 1674-5752, Vol. 6, no 6, p. 1-3Article in journal (Other academic)
  • 538.
    Ziesig, R.
    et al.
    RISE, Innventia.
    Tomani, P.
    RISE, Innventia.
    Theliander, H.
    Production of a pure lignin product part 2: Separation of lignin from membrane filtration permeates of black liquor2014In: Cellulose Chemistry and Technology, ISSN 0576-9787, Vol. 48, no 9-10, p. 805-811Article in journal (Refereed)
  • 539.
    Ziesig, Rufus
    et al.
    RISE, Innventia.
    Sedin, Maria
    RISE, Innventia.
    Tomani, Per
    RISE, Innventia.
    Theliander, Hans
    RISE, Innventia. Chalmers University of Technology, Sweden.
    Production of a pure lignin product, Part 3: Distribution and removal of inorganics from softwood lignin2015In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 30, no 2, p. 199-206Article in journal (Refereed)
    Abstract [en]

    Future high value lignin-based products, such as carbon fibers, require a lignin raw material essentially free from inorganic impurities. Lignin of low inorganic content can be separated from kraft black liquor by the LignoBoost process. This laboratory scale study focuses on the effect of process parameters, such as pH and retention time in re-suspension, on the content of inorganic impurities in the LignoBoost lignin. Black liquor from pulping of softwood was used in this study. Specific attention was paid to the elements Na, K, Al, Ba, Ca, Fe, Mg, Mn and Si. It was found that the softwood lignin contained significantly less Ca, resulting in lower ash content, than eucalyptus lignin separated in earlier studies made in this series. Inorganic particles, containing for example Ca-O and Na-Al-Si, were observed in the washed lignin. Prolonged retention time in the re-suspension stage reduced the content of Ca, Mn, Mg, Fe and Si in the washed lignin. A reduction of the content by 30-50% after 24 h was possible. The rate at which these elements are removed from the agglomerates was found to be dependent on the mixing conditions, which indicates that the mass transfer in the liquid film around the particles is of importance for the total mass transfer resistance.

  • 540.
    Ziesig, Rufus
    et al.
    RISE, Innventia.
    Tomani, Per
    RISE, Innventia.
    Schweinebarth, Hannah
    RISE, Innventia.
    Norberg, Lars
    RISE, Innventia.
    Theliander, Hans
    RISE, Innventia.
    Production of a pure lignin product: part 1: distribution and removal of inorganics in Eucalyptus Globulus kraft lignin2013Conference paper (Refereed)
  • 541.
    Ziesig, Rufus
    et al.
    RISE, Innventia.
    Tomani, Per
    RISE, Innventia.
    Schweinebarth, Hannah
    RISE, Innventia.
    Norberg, Lars
    RISE, Innventia.
    Theliander, Hans
    RISE, Innventia.
    Production of a pure lignin product, part 1: Distribution and removal of inorganics in Eucalyptus globulus kraft lignin2014In: TAPPI Journal, ISSN 0734-1415, Vol. 13, no 3, p. 65-72Article in journal (Refereed)
  • 542.
    Ålander, Eva
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy.
    ֖stlund, Ida
    RISE - Research Institutes of Sweden, Bioeconomy.
    Lindgren, Karin
    RISE - Research Institutes of Sweden, Bioeconomy.
    Johansson, Malin
    RISE - Research Institutes of Sweden, Bioeconomy.
    Gimåker, Magnus
    RISE - Research Institutes of Sweden, Bioeconomy.
    Towards a more cost-efficient paper and board making using microfibrillated cellulose2017In: The 7th Nordic Wood Biorefinery Conference held in Stockholm, Sweden, 28-30 Mar. 2017: NWBC 2017, Stockholm: RISE Bioekonomi , 2017, p. 49-54Conference paper (Refereed)
    Abstract [en]

    The economic potential in terms of variable cost needed for production of fine paper has been evaluated for a case where microfibrillated cellulose (MFC) was added in order to increase the filler content at maintained grammage and tensile index. MFC production was based on a mechanical enzymatic pretreatment procedure prior to high-pressure homogenisation. Two different scenarios were studied: without and with wet end starch. For cost evaluation, it was assumed that the cost for production MFC had been calculated from the pulp and enzyme price and energy needed for refining and homogenisation. Although the pulp used was a never-dried bleached softwood sulphite pulp, the price was assumed to be equal to that for bleached kraft pulp. Techno-economic analysis was based on a pilot scale trial using a mobile demonstration plant with a capacity to produce 100kg MFC. The plant consisted of a three-stage process: enzyme treatment, refining and homogenisation. It has been concluded that the use of MFC as a strength additive had a positive impact on the variable costs for a fine paper case when increasing the filler content.

  • 543.
    Åslund, Peter
    et al.
    RISE, STFI-Packforsk.
    Vomhoff, H.
    RISE, STFI-Packforsk.
    Dewatering mechanisms and their influence on suction box dewatering processes: A literature review2008In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 23, no 4, p. 389-397Article, review/survey (Refereed)
    Abstract [en]

    This review summarizes the present knowledge of suction box dewatering mechanisms. In addition, existing and novel suction box dewatering processes are described for applications in the pulp and paper industry. Three mechanisms that determine the dry content of the web after suction box dewatering are identified, viz. web compression, displacement of water by air, and rewetting. Earlier work focused mainly on the influence of web properties and process parameters for the achievable dry content. That work did not give any information concerning the relative importance of the three mechanisms. There was no measurement of web compression or water displacement. Furthermore, the occurrence of rewetting was neglected by many researchers. A deeper knowledge and, above all, direct measurements are required to better describe suction box dewatering. Some interesting modified suction box dewatering processes were presented in the literature. For example, the use of a membrane on top of the web during dewatering is believed to have the potential for an increase in dry content and energy savings. This increase in dry content is consequently believed to be a result of an increase in web compression.

  • 544.
    Ņslund, Peter
    et al.
    RISE, STFI-Packforsk.
    Vomhoff, Hannes
    RISE, STFI-Packforsk.
    Evaluation of membrane-assisted dewatering on a pilot paper machine2008In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 23, no 2, p. 152-155Article in journal (Refereed)
    Abstract [en]

    A membrane-assisted dewatering process was evaluated on a pilot paper machine. In this process, a membrane is located on top of the wet web when it passes over the suction box in the forming section. The intentions are twofold. Firstly, the dry content of the web should be increased by a more uniform compression, primarily in the thickness direction. Secondly, the airflow into the suction box should be reduced. The trials were performed using a specially designed membrane loop located at the end of the fourdrinier forming section of STFI-Packforsk’s pilot paper machine EuroFEX. Two different membranes were tested. The use of a membrane resulted in a significant decrease in air consumption to achieve the same dry content of the web at the end of the wire section. To increase the dry content of the web, the structure of the membrane is important.

  • 545.
    Åslund, Peter
    et al.
    RISE, STFI-Packforsk.
    Vomhoff, Hannes
    RISE, STFI-Packforsk.
    Method for studying the deformation of a fibre web during a suction pulse2008In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 23, no 4, p. 398-402Article in journal (Refereed)
    Abstract [en]

    A laboratory suction box was built to study the dynamic thickness deformation of a fibre web during a suction pulse. Both the pressure in the suction box and the duration of the suction pulse are adjustable in ranges of 0 to -40 kPa and 50 ms to 10 s, respectively. During and after the suction pulse, the web thickness and the suction pressures can be measured. Furthermore, the air flow through the web can be calculated after the experiment. The first evaluation of the performance of the laboratory suction box shows that the web is considerably compressedaaaa especially during the initial phase of the suction pulse. This indicates that web compression is an important dewatering mechanism. After the suction pulse, a rapid and significant web expansion was observed, implying that considerable rewetting probably occurs.

  • 546.
    Åslund, Peter
    et al.
    RISE, STFI-Packforsk.
    Vomhoff, Hannes
    RISE, STFI-Packforsk.
    Waljanson, Alexander
    RISE, STFI-Packforsk.
    External rewetting after suction box dewatering2008In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 23, no 4, p. 409-414Article in journal (Refereed)
    Abstract [en]

    A method has been developed to enable external rewetting to be measured during suction box dewatering. In a laboratory suction box, webs were instantaneously separated from the forming fabric at defined times, both during and after the suction pulse. External rewetting was measured for webs of mechanical (50, 100 g/m2) and chemical pulp (100, 200 g/m 2). Suction pulses with a pressure drop of 10 and 40 kPa, and duration of 50 to 1000 ms were used. A considerable external rewetting was observed occurring primarily directly after the end of the suction pulse. Under the process conditions investigated, rewetting accounted for a dry content decrease of between 3 and 6%.

  • 547. Östlund, A.
    et al.
    Idström, Alexander
    Chalmers University of Technology, Sweden.
    Olsson, Carina
    Chalmers University of Technology, Sweden.
    Larsson, P.T.
    RISE, Innventia.
    Nordstierna, L.
    Modification of crystallinity and pore size distribution in coagulated cellulose films2013In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, no 4, p. 1657-1667Article in journal (Refereed)
  • 548.
    Östlund, Catherine
    RISE - Research Institutes of Sweden, Bioeconomy, Papermaking and Packaging.
    Towards total production monitoring of basis weight and moisture2018In: PaperCon 2018: Shaping the future through innovation, TAPPI , 2018, p. 313-316, article id CS3.2Conference paper (Refereed)
    Abstract [en]

    Measurement methods using infrared (IR) camera techniques have been developed and evaluated, both in laboratorystudies, online on the FEX pilot paper machine, and at paper mills. The large advantage with the methods we developedfor applying the high-speed IR cameras on the paper machine is the ability to cover the whole width of the machine toview temperature changes over a longer period of time. The temperature changes can then be correlated to processvariations (i.e. moisture or material distribution) to obtain the local basis weight variation, to achieve more detailedinformation for an optimisation of the process.

  • 549.
    Östlund, Catherine
    et al.
    RISE, Innventia.
    Vomhoff, Hannes
    RISE, Innventia.
    Christiansson, Hans
    RISE, Innventia.
    Advanced image based measurement techniques for analysis of process variations2016In: Paper Conference and Trade Show (PaperCon 2016), 2016, Vol. 2, p. 871-878Conference paper (Refereed)
    Abstract [en]

    The Swedish research institute Innventia has taken a look into what the future needs will be for online measurements techniques in paper production. Discussions in a group consisting of experts from industry and academy, of paper and board production, measurement techniques, analysis methods and quality control systems resulted in a roadmap describing tomorrow’s needs of new applications of measurement techniques. The starting point was a vision of a high-resolution, multispectral online analysis of the complete produced area combined with new approaches for interpretation of measurements, to give better and more complete information of the paper production. One approach is to combine modern infrared (IR) imaging systems with data from the existing quality control systems in order to obtain the local grammage variation, to achieve more detailed information for optimisation of the process. The IR camera technique has been studied at the institute for 7 years, both in laboratory studies and at mills. Another online measurement technique that has been developed and studied is the online optical topography system OptiTopo. This gives information of the surface structure variation both in fine-scale and in large-scale. This instrument also gives valuable input in the quality control system. Examples from the two systems are shown.

  • 550.
    ֖stlund, Ida
    et al.
    RISE, Innventia.
    Bjärestrand, Annika
    RISE, Innventia.
    Wiberg, Anna
    RISE, Innventia.
    Söderberg, Daniel
    RISE, Innventia.
    Impact of the morphology of SGW fibres and fines om sheet properties2012Conference paper (Refereed)
89101112 501 - 550 of 552
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
v. 2.35.8