Relevant bibliographies by topics / Densified wood

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Densified wood'

Author: Grafiati
Published: 4 June 2021
Last updated: 14 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Densified wood.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Densified wood"

1

Navi, Parviz, and Fred Girardet. "Effects of Thermo-Hydro-Mechanical Treatment on the Structure and Properties of Wood." Holzforschung 54, no. 3 (April 13, 2000): 287–93. http://dx.doi.org/10.1515/hf.2000.048.

Full text
Abstract:
Summary A process has been developed for densifying wood by thermo-hydro-mechanical (THM) means. The resulting product is then called THM densified wood. Small specimens of different wood species, with or without knots, were densified in their radial, tangential and transversal directions. Tests on THM densified wood show significant improvement in mechanical properties. THM densified wood is less hygroscopic and more stable, with almost no shape memory. We have shown that the shear strength of wood in its grain direction increases more than tenfold by THM treatment. This article gives testing results and micrographs of THM densified wood, and discusses the physical nature of different mechanisms intervening at the wood cell wall level during the thermo-hydro-mechanical process.
APA, Harvard, Vancouver, ISO, and other styles
2

Schwarze, Francis W. M. R., and Melanie Spycher. "Resistance of thermo-hygro-mechanically densified wood to colonisation and degradation by brown-rot fungi." Holzforschung 59, no. 3 (May 1, 2005): 358–63. http://dx.doi.org/10.1515/hf.2005.059.

Full text
Abstract:
Abstract Colonisation and wood degradation by three brown-rot fungi, Coniophora puteana, Gloeophyllum trabeum and Poria placenta, were studied in wood of Norway spruce (Picea abies) subjected to three different treatments: hygro-thermal (TH) (160 and 180°C), mechanical densification and thermo-hygro-mechanical (THM) treatment including densification and post-treatment under saturated steam conditions at different temperatures (140, 160 and 180°C). The weight loss induced by all three fungi was lowest in THM-densified wood post-treated at 180°C. Highest weight losses were recorded for controls and TH-treated wood. Fungal colonisation varied in its intensity, depending on the treatment applied to the wood. Hyphal growth in controls and TH-treated wood was abundant, whereas in densified and THM-densified wood it was sparse and confined predominantly to the cell lumina of earlywood tracheids. Also, penetration of large-diameter hyphae and associated degradation in THM-densified wood was impeded by occlusion of the lumina, associated with irreversible compression (loss in shape memory). In contrast to C. puteana and P. placenta, which showed typical brown-rot behaviour, G. trabeum frequently showed hyphal tunnelling within the secondary walls of tracheids and xylem ray parenchyma of controls and thermally treated wood. Such growth was never observed in THM-densified wood post-treated at 180°C.
APA, Harvard, Vancouver, ISO, and other styles
3

Xiang, Elin, Rongfeng Huang, and Shumin Yang. "Change in Micromechanical Behavior of Surface Densified Wood Cell Walls in Response to Superheated Steam Treatment." Forests 12, no. 6 (May 28, 2021): 693. http://dx.doi.org/10.3390/f12060693.

Full text
Abstract:
The combination of surface densification and superheated steam treatment is an effective method to improve the mechanical properties and dimensional stability of low-density wood. The objective of the current work is to evaluate the effects of superheated steam treatment on the micromechanical behavior of surface densified wood. The microstructure, chemical composition, cellulose crystalline structure, and micromechanical behavior of surface densified wood under different superheated steam pressures were investigated. Results indicated that both 0.1 MPa and 0.3 MPa superheated steam treatments increased the elastic modulus and hardness of fiber cell walls in surface densified wood. However, the average creep ratio and maximum creep compliance J(50) of surface densified wood under 0.3 MPa decreased by 41.59% and 6.76%, respectively, compared with untreated wood. The improvement of elastic modulus, hardness and creep resistance of surface densified wood treated with superheated steam was associated with the increase of relative crystallinity (CrI) and crystalline size. In addition, 0.3 MPa superheated steam treatment displayed a better effect on the enhancement of the elastic modulus, hardness, and creep resistance of the fiber cell wall than 0.1 MPa superheated steam treatment.
APA, Harvard, Vancouver, ISO, and other styles
4

RADOMSKI, ANDRZEJ, and MARTA GNACIŃSKA. "The study of the impact of in situ polymerisation with styrene or acrylates on water absorbability and swelling of thermomechanically densified poplar wood." Annals of WULS, Forestry and Wood Technology 108 (October 31, 2019): 140–47. http://dx.doi.org/10.5604/01.3001.0013.7701.

Full text
Abstract:
The study of the impact of in situ polymerisation with styrene or acrylates on water absorbability and swelling of thermomechanically densified poplar wood. Black poplar samples, which were previously subjected to thermomechanical densification, were tested for an improvement on the field of water resistance. Series of samples were additionally thermally treated in a nitrogen atmosphere, and then series of densified only or densified and thermally treated samples were treated with monomer mixtures, containing styrene or acrylates, and co-monomers reactive toward cell wall of wood, followed by thermally induced radical polymerisation. All samples were tested by prolonged soaking in water, while volume swelling and absorbability were determined. Densified wood proved to be suitable for modification by in situ polymerisation. Thermally treated densified wood was found to be significantly more compatible with polymers used, as a decrease in its swelling was observed as dominant effect, while absorbability changes were less clear.
APA, Harvard, Vancouver, ISO, and other styles
5

Mania, Przemysław, Miłosz Wróblewski, Adam Wójciak, Edward Roszyk, and Waldemar Moliński. "Hardness of Densified Wood in Relation to Changed Chemical Composition." Forests 11, no. 5 (May 1, 2020): 506. http://dx.doi.org/10.3390/f11050506.

Full text
Abstract:
The aim of this study was to evaluate some of the properties of densified poplar and birch wood earlier subjected to partial delignification of cell walls. The effects of delignification are presented as a comparison of the content of basic structural components in wood before and after chemical modification. In birch wood, the lignin content decreased by 20%, while that of cellulose decreased by 9.7% and that of hemicellulose decreased by 64.9%. In poplar, the lignin content decreased by 34.1%, that of cellulose decreaed by 13.5%, and that of hemicellulose decreased by 58.0%. The hardness of densified birch and poplar wood, after partial reduction of chemical components, was 147 and 111 MPa, respectively, and, compared with natural (non-densified) wood, was almost 4.5 times and 7 times higher, respectively. Poplar wood was more densified (without delignification 238% and after delignification 281%). In the case of birch wood, the density levels were 176% and 188%, respectively.
APA, Harvard, Vancouver, ISO, and other styles
6

Laine, Kristiina, Kristoffer Segerholm, Magnus Wålinder, Lauri Rautkari, Graham Ormondroyd, Mark Hughes, and Dennis Jones. "Micromorphological studies of surface densified wood." Journal of Materials Science 49, no. 5 (December 3, 2013): 2027–34. http://dx.doi.org/10.1007/s10853-013-7890-8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Jakob, Matthias, Gregor Stemmer, Ivana Czabany, Ulrich Müller, and Wolfgang Gindl-Altmutter. "Preparation of High Strength Plywood from Partially Delignified Densified Wood." Polymers 12, no. 8 (August 11, 2020): 1796. http://dx.doi.org/10.3390/polym12081796.

Full text
Abstract:
Wood and natural fibers exhibit an advantageous combination of good mechanics at comparably low density. Nevertheless, comparing absolute strength and stiffness, wood is clearly inferior to materials such as metals and engineered composites. Since there is a strong correlation between wood density and wood mechanical performance, densification by transversal compression suggests itself as a route towards improved mechanics. Partially delignified densified spruce veneers with excellent tensile properties were produced by means of an alkaline (AL) and an organosolv (OS) approach. Plywood specimens were manufactured using treated veneers glued with a phenol-resorcinol-formaldehyde adhesive and were compared with plywood samples made of native spruce veneers (Ref) and spruce veneer densified after plasticization by water impregnation (H2O). Roughly, the bending strength and the modulus of elasticity of plywood from partially delignified densified wood were improved by a factor of 2.4 and 3.5, respectively. Interlaminar shear strength did not match this improvement after partial delignification. Together with excessive thickness swelling, this might be a drawback of partially delignified densified wood in need for further research.
APA, Harvard, Vancouver, ISO, and other styles
8

Neyses, Benedikt, Olov Karlsson, and Dick Sandberg. "The effect of ionic liquid and superbase pre-treatment on the spring-back, set-recovery and Brinell hardness of surface-densified Scots pine." Holzforschung 74, no. 3 (February 25, 2020): 303–12. http://dx.doi.org/10.1515/hf-2019-0158.

Full text
Abstract:
AbstractCompressing the surface of sawn timber results in a substantial increase in hardness, and this opens up new market opportunities of using low-density timber species as the raw material for high-value wood products. Unfortunately, widespread commercialisation is hindered by the lack of an industrially viable surface densification process, the major obstacle being the set-recovery (SR) of the densified wood cells upon exposure to moisture. Our hypothesis is that partial dissolution of the crystalline cellulose during densification will largely prevent the SR of densified wood. We therefore evaluated the effect of ionic liquid (IL) or organic superbase pre-treatment on the elastic spring-back (SB), SR and Brinell hardness (HB) of surface-densified wood. Specimens of Scots pine were treated with solutions of ILs or superbases, and then densified in a hot press at temperatures between 200°C and 270°C. The SR was reduced from 90% for the control group to only about 10% for the treated materials. The treated and densified specimens exhibited a higher HB than their untreated and densified counterparts. The method presented in this study is a precursor to the development of a continuous densification process adapted for an open system. Further studies are needed to understand the underlying mechanisms of the pre-treatment.
APA, Harvard, Vancouver, ISO, and other styles
9

Laskowska, Agnieszka, and Janusz W. Sobczak. "Surface chemical composition and roughness as factors affecting the wettability of thermo-mechanically modified oak (Quercus robur L.)." Holzforschung 72, no. 11 (November 27, 2018): 993–1000. http://dx.doi.org/10.1515/hf-2018-0022.

Full text
Abstract:
AbstractEuropean oak wood (W) was thermo-mechanically modified (TM) via densifying at 100 and 150°C and the surface properties of the TMW were investigated. The contact angle (CA) of the wood with the reference liquids water and diiodomethane was determined using the sessile drop method. The surface free energy of the TMW on tangential sections within the first 60 s after applying a drop was analyzed. The roughness parameters Ra and Rz parallel (‖) and perpendicular (⊥) to the grain were investigated. The wettability analysis showed that densified wood had a higher CA and lower work of adhesion and surface free energy than non-densified wood. An X-ray photoelectron spectroscopy [XPS or electron spectroscopy for chemical analysis (ESCA)] analysis showed that the oxygen to carbon atoms ratio (O/C ratio) of densified wood surface was lower than that of non-densified wood. The carbon C1-C2 atoms ratio (C1/C2 ratio) increased with increasing TM temperature. The results were interpreted as being that extractives migrate to the surface and amorphous and glassy polymers, i.e. lignin and hemicelluloses, in wood are rearranged. Increasing densification temperature makes TMW surfaces more hydrophobic.
APA, Harvard, Vancouver, ISO, and other styles
10

Jakob, Matthias, Jakob Gaugeler, and Wolfgang Gindl-Altmutter. "Effects of Fiber Angle on the Tensile Properties of Partially Delignified and Densified Wood." Materials 13, no. 23 (November 27, 2020): 5405. http://dx.doi.org/10.3390/ma13235405.

Full text
Abstract:
Partial delignification and densification provide a pathway to significant improvement in the mechanical performance of wood. In order to elucidate potential effects of this treatment on the mechanical anisotropy of wood, partially delignified and densified spruce wood veneers were characterized at varying degrees of off-axis alignment. While the tensile strength and the modulus of elasticity (MOE) were clearly improved in parallel to the axis of wood fibers, this improvement quickly leveled off at misalignment angles ≥30°. For transverse tensile strength, the performance of alkaline-treated and densified wood was even inferior to that of untreated wood. Microscopic examination revealed the presence of microscopic cracks in treated wood, which are assumed to be responsible for this observation. It is concluded that impaired transverse tensile properties are a weakness of partially delignified and densified wood and should be considered when a potential usage in load-bearing applications is intended.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Densified wood"

1

Kultikova, Elena V. "Structure and Properties Relationships of Densified Wood." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/35810.

Full text
Abstract:
The objective of this research was to investigate the effect of applied compressive strain in various environments, on the strength and stiffness of compressed wood samples. It is believed that transverse compression of wood at specific conditions of temperature and moisture will result in improved mechanical properties, which can be attributed to increased density and perhaps other physical or chemical changes.

Specimens of both mature and juvenile southern pine (Pinus taeda) and yellow-poplar (Liriodendron tulipifera) were compressed radially at three different temperature, and moisture content conditions relevant to the glass transition of wood.

Ultimate tensile stress and longitudinal modulus of elasticity were obtained by testing compressed, uncompressed and control samples in tension parallel-to-grain. Strain measurements were performed using laboratory-built clip-on strain gauge transducers. Results of the tensile tests have shown an increase in the ultimate tensile stress and modulus of elasticity after all densification treatments.

Scanning electron microscopy was employed for observing changes in cellular structure of densified wood. Existence of the cell wall fractures was evaluated using image processing and analysis software. Changes in cellular structure were correlated with the results of the tensile test.

Chemical composition of wood samples before and after desorption experiments was determined by acid hydrolysis followed by high performance liquid chromatography (HPLC). The results of the chemical analysis of the wood specimens did not reveal significant changes in chemical composition of wood when subjected to 160 °C, pure steam for up to 8 hours.

The results of this research will provide information about modifications that occur during wood compression and will result in better understanding of material behavior during the manufacture of wood-based composites. In the long run, modification of wood with inadequate mechanical properties can have a significant effect on the wood products industry. Low density and juvenile wood can be used in new high-performance wood-based composite materials instead of old-growth timber.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles
2

Arulappan, Pushparaj Victor. "Fabrication and Analysis of High-Performance Thermochemically Densified Wood." Wright State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wright162203579660275.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Blomberg, Jonas. "Compression mechanisms and strength properties of semi-isostatically densified wood /." Luleå, 2004. http://epubl.luth.se/1402-1757/2004/07.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Skyba, Oleksandr. "Durability and physical properties of thermo-hygro-mechanically (THM)-densified wood /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17855.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Jennings, Jessica D. "Investigating the Surface Energy and Bond Performance of Compression Densified Wood." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/10150.

Full text
Abstract:
The bond performance and surface energy of hygro-thermal compression densified wood were studied using comparisons to hygro-thermally treated and control yellow-poplar (Liriodendron tulipifera). Bond performance was studied using opening mode double cantilever beam fracture testing and cyclic boiling of one half of all fracture samples. Phenol formaldehyde film (PF-film) and polymeric diphenylmethane diisocyanate (pMDI) were the two different adhesives used to bond fracture samples. Hygro-thermal samples bonded with PF-film had significantly higher fracture toughness than control samples, while no difference was found for densified samples. Densified samples bonded with pMDI had significantly higher fracture toughness than control samples while no change was seen for hygro-thermal samples. Boil cycling reduced fracture toughness of hygro-thermal fracture samples only, irrespective of adhesive type. Surface energy was studied using sessile drop contact angle measurement and the Chang model of acid-base, surface energy component calculation. Water, glycerol, formamide, ethylene glycol, and -Bromonapthalene were used as probe liquids. Densified and hygro-thermally treated yellow-poplar had significantly higher contact angles than control samples. The contact angle trends for densified and hygro-thermally treated wood were found to be the same. Total surface energy as well as the polar and acid components of surface energy decreased with hygro-thermal treatment. The dispersive and base components of surface energy increased with hygro-thermal treatment.
Master of Science
APA, Harvard, Vancouver, ISO, and other styles
6

Neyses, Benedikt. "Surface-Densified Wood : From Laboratory-Scale Research Towards a Competitive Product." Licentiate thesis, Luleå tekniska universitet, Träteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-60282.

Full text
Abstract:
For many decades, humans have been consuming more resources than the world has to offer in the long run. Increasing the use of renewable materials, such as wood, is essential if we are to achieve a sustainable use of the resources available to us. Densification of wood in general, and surface densification in particular, has the potential to improve the properties of widely available low-density wood species, opening up new fields of application, and fostering the use of wood products in general. The objective of this thesis is to put past research within the field of surface densification of solid wood and advancements within the present project into a context, and to suggest a path towards a performance-driven and cost-effective type of product. A prevalent research gap has been identified and this thesis summarizes how this gap can be filled by already conducted and future studies. Important aspects that need be handled in order to fulfill the overall vision of the large-scale commercialization of surface-densified wood products are considered. Past studies were successful in gaining a good understanding of different approaches to the densification of solid wood, such as using a hot press or a friction welding machine. Problems, such as the moisture-induced recovery of the densified wood cells could be solved from a technological perspective. However, those studies did not take into account industrial implementation. Existing methods are time- and/or energy-consuming. The use of roller-pressing equipment showed promising results, but also highlighted certain limitations. Solid wooden boards have been successfully surface-densified at speeds of up to 80 m/min. However, problems arose regarding the plasticization and stabilization of the densified wood cells, indicating that a continuous belt-press approach might be more viable with regard to the objective of industrial implementation. In parallel, a structured method to identify the most suitable wood species for surface densification has been presented, with the aim of propagating the use of surface-densified wood products and widening their fields of application. This method has confirmed the suitability of previously used wood species, and has also suggested alternatives not considered thus far. Previous studies into the surface densification of wood have provided a rather sound understanding of the densification process and have provided a useful foundation for the current project. The work done, thus far, has shown the viability of a continuous densification process and has indicated a sensible path towards the widespread establishment of surface-densified wood products on the market.
APA, Harvard, Vancouver, ISO, and other styles
7

Han, Lei. "Reduction of Set-recovery of Surface densified Scots Pine by Furfuryl Alcohol." Thesis, Luleå tekniska universitet, Träteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-75368.

Full text
Abstract:
For wood products such as flooring and worktop, only one surface is normally exposed in their use, and the mechanical properties like hardness and wearing resistance of that surface is then important. Since mechanical properties are strongly related to the density, surface densification, i.e. transverse compression of the wood cells beneath the surface of a piece of wood with the aim to increase the density of that region, may be a method for improving hardness and wearing resistance when low-density species are used for such products. The set-recovery, i.e. the moisture-induced swelling of the densified wood cells back to their original shape, is the main obstacle in the use of densified wood products. Although there are several methods reported in literature, such as post heat-treatment, that can almost eliminate the set-recovery, but such methods are either time consuming or difficult to implement into an industrial continuous process which may do densification competitive to techniques or materials that can achieve at least the same hardness.     In the present study, furfuryl alcohol was used as pre-treatment to fix the set-recovery of surface-densified Scots pine sapwood. The main effect and interactive influence of four process parameter (impregnation time, press temperature, press time and compression ratio) on set-recovery and Brinell hardness after two wet-dry cycles were studied by a two-level full factorial design of experiments. The characterizing variables of the density profile after the surface densification and set-recovery test were carried out as a supplementary tool to learn the mechanism of this two-step modification process. According to the result, the surface densified wood with furfuryl alcohol pre-treatment can retain their dimension and keep hardness at a very high level after two wet-dry cycles. The set-recovery and hardens after two wet-dry cycles were about 20 % and 30 N/mm2, respectively. The Pearson correlation analysis shows that the correlation coefficients between set-recovery with impregnation time, press temperature, press temperature, compression ratio were -0.35, -0.52, -0.37, and 0.16, respectively. That means that for the specimens with furfuryl alcohol pre-treatment, the higher press temperature can reduce the set-recovery significantly. The longer press time and impregnation time can also reduce the set-recovery in some extent, but the influence was  low. As expected, the hardness improvement was retained with low set-recovery. The lowest set-recovery value was 14% with the corresponding hardness of 41 N/mm2 was achieved by specimens processed with 120 minutes of impregnation, 10% compression ratio, 210℃ pressing temperature, and 15 minutes of pressing time. With 20 minutes of impregnation time, 10% compression ratio, 210℃ pressing temperature, and 5 minutes of pressing time, the sample still owns twofold hardness after the set-recovery test.
APA, Harvard, Vancouver, ISO, and other styles
8

Buchelt, Beate, Tobias Dietrich, and André Wagenführ. "Testing of set recovery of unmodified and furfurylated densified wood by means of water storage and alternating climate tests." De Gruyter, 2014. https://tud.qucosa.de/id/qucosa%3A38557.

Full text
Abstract:
Densification is a well-known method for improving the mechanical properties of wood. In the present study, unmodified and furfurylated wood samples were densified and submitted to cyclic water storage tests and cyclic alternating climate tests. Swelling coefficients and spring-back data were determined for the evaluation of the quality of densification. The study shows that results depend on the test method applied. Simple water storage tests do not reflect the behavior of densified wood in the high humidity range. The spring-back data of unmodified samples are more influenced by the testing method than those of the furfurylated ones.
APA, Harvard, Vancouver, ISO, and other styles
9

Ashna, Emran, and Amir Dashti. "Kan trämaterialet DDW ersätta stål vid konstruktion av framtida gång- och cykel broar : Jämförelse utifrån LCC." Thesis, KTH, Byggteknik och design, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231744.

Full text
Abstract:
I detta examensarbete behandlas en jämförelse mellan två olika material utifrån LCC för GC-broar. Dessa är stål och Delignified Densified Wood (DDW). Samhället är i behov av att utvecklas inom ett mer hållbart- och anpassad till klimatkraven. Detta innebär att det ställs krav på Trafikverket. Dessa krav innebär bland annat att byggnadsmaterial behöver utvecklas. Sverige har god tillgång till skog och träframtagning. Trafikverket bör nyttja mer av träets potential. Denna studie har därför gjorts för att bedöma DDW som är ett träbaserat material utifrån intervjuer och livscykelkostnadsanalys (LCC-analys). LCC är ett tillvägagångsätt för att få en totalbild över en produkts samtliga kostnader under dess livslängd. Det vill säga att för en bro bedöms kostnaderna från projektering till rivning. Syftet med LCC-analys är att hitta den mest lönsamma investeringskostnad som uppfyller dagens samhällskrav. DDW är framtagen av Forskare vid Marylands Universitet. Forskningen har observerat att obehandlat trä går att få lika starkt som stål. Processen innebär att ligninet avlägsnas och träet placeras i tryck under värme på cirka 100 C°. Detta leder till att cellulosafibrerna pressas samman och blir hårdare. Det resulterar förenklat sagt att träet blir mycket hårdare, tåligare och starkare och går att forma och böja. Resultatet av examensarbetet tyder på att DDW inte är lämpligt just nu som konstruktionsmaterial i utomhusklimat och inte är ekonomiskt lönsamt. DDW är vetenskapligt intressant och bör forskas vidare. I dagsläget rekommenderas inte DDW som GC-bromaterial. Trafikverket bör bygga mer GC- broar av trä som passar väl som GC-bromaterial.
n this thesis a comparison is made between two different construction materials based on LCC for pedestrian and cycle bridges. These materials are steel and Delignified Densified Wood (DDW). Today ́s society needs to develop with more sustainable and climate-friendly construction. This need imposes demands on the Swedish transport administration, e.g. that building materials need to be developed. One viable material for Sweden, since it has good access to forestry and wood production, is wood. The Swedish transport administration should use more of the potential of wood. This study therefore assesses DDW, which is a wood-based material, based on interviews and life cycle cost analysis (LCC-analysis). LCC is a way of getting a complete picture of a product's entire costs during its lifespan. In the case of a bridge, the costs are estimated from planning to demolition. The purpose of LCC analysis is to find the most profitable investment cost that meets today's social requirements. DDW is developed by researchers at Maryland University. Researchers have observed that natural wood can be as strong as steel. The process involves removing lignin and placing it under pressure at a temperature of about 100 ° C. This causes the cellulosic fibers to compress and become harder. This simply means that the wood becomes much harder, more durable and stronger, and can also shape and bend. The result of the thesis suggests that DDW is not suitable at present as construction material in outdoor climate and is not economically profitable. DDW is scientifically interesting and should be researched further.
APA, Harvard, Vancouver, ISO, and other styles
10

El, Houjeyri Imane. "Expérimentation et modélisation du comportement des assemblages en bois réalisés par des tourillons en bois densifié sous des charges monotones et cycliques." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0236.

Full text
Abstract:
Il s’agit de travailler sur des poutres multicouches (ou panneaux en bois lamellé-croisé assemblées mécaniquement par des tourillons en bois densifié. Traditionnellement, ce type de poutre, appelé poutre en bois lamellé-collé, est obtenu par collage des lamelles en bois, ce qui assure une liaison « parfaite » conduisant ainsi à une poutre (ou plaque) multicouches dont les caractéristiques peuvent être obtenues par homogénéisation. Dans le sujet proposé, il s’agit de remplacer la colle par des liaisons effectuées par des tourillons en bois densifié. La viabilité des poutres (ou panneaux) assemblées par tourillons en bois densifié (plus écologiques) n’est pas encore tout à fait démontrée et reste donc exploratoire. L’analyse de ce type de structures (en statique ou en dynamique) doit prendre en compte le fait que la liaison entre les lamelles est semi-rigide. Donc, il est justement prévu de caractériser expérimentalement et à grande échelle ce type de structures. L’objectif principal de la thèse proposée est d’évaluer la réponse structurelle sous charges monotone et cyclique. Plus particulièrement, la réponse sous charge cyclique est évidement un paramètre clé pour la validation de ce type d’assemblage sous charge sismique. Dans le cadre de cette étude, il est envisagé d’utiliser la simulation numérique (utilisation d’Abaqus) afin de réduire les tests expérimentaux couteux et d’optimiser les choix de conception retenus
It is a question of working on multi-layered beams (or cross-laminated wood panels assembled mechanically by densified wood dowels) Traditionally, this type of beam, called laminated beam, is obtained by gluing wooden laminates. which ensures a "perfect" connection thus leading to a multi-layer beam (or Panels) whose characteristics can be obtained by homogenization. In this work, it proposed to replace the glue by the densified wood dowels to make the assemblies. The viability of beams (or panels) assembled by densified wood dowels (more ecological) is not yet fully demonstrated and therefore remains exploratory. The analysis of this type of structure (static or dynamic) must consider the fact that the connection between the wood parts is semi-rigid. therefore, it is precisely planned to characterize this type of structure experimentally and on a large scale. The main objective of the proposed thesis is to evaluate the structural response under monotonic and cyclic loads. More particularly, the response under cyclic load is obviously a key parameter for the validation of this type of assembly under seismic load. As part of this study, it is envisaged to use numerical simulation (use of Abaqus) to reduce expensive experimental tests and optimize the chosen design choices
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Densified wood"

1

Matolcsy, G. A. Development of a moisture resistant densified solid fuel from forest biomass. Ottawa: The Dept., 1986.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

MacEachen, I. L. Production of densifield, water-resistant biomass fuel: Final report. Pointe Claire, Quebec: Pulp and Paper Research Institute of Canada, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

The World Market for Densified Wood and Reconstituted Wood: A 2004 Global Trade Perspective. Icon Group International, Inc., 2005.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Parker, Philip M. The World Market for Densified Wood and Reconstituted Wood: A 2007 Global Trade Perspective. ICON Group International, Inc., 2006.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

The World Market for Densified Wood in Blocks, Plates, Strips, or Profile Shapes: A 2004 Global Trade Perspective. Icon Group International, Inc., 2005.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Densified wood"

1

Carre, J., L. Lacrosse, and Y. Schenkel. "Comparison between Wood Gasification and Densified Briquettes Gasification." In Research in Thermochemical Biomass Conversion, 655–66. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2737-7_50.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Haller, Peer, and Jörg Wehsener. "Use of Technical Textiles and Densified Wood for Timber Joints." In Materials for Buildings and Structures, 66–71. Weinheim, FRG: Wiley-VCH Verlag GmbH & Co. KGaA, 2005. http://dx.doi.org/10.1002/3527606211.ch10.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Densified wood"

1

Raatikka, Luther M. "Woody Biomass Co-Firing in Pulverized Coal Fired Boilers." In ASME 2011 Power Conference collocated with JSME ICOPE 2011. ASMEDC, 2011. http://dx.doi.org/10.1115/power2011-55300.

Full text
Abstract:
With legislation requiring utilities to produce a significant fraction of their electrical energy with renewable fuel supplies, it is anticipated that cofiring biomass in large utility boilers will become increasingly popular. Boilers that are designed to burn pulverized coal (PC) can typically burn woody biomass at up to 5% of the rated heat input. An 800 MW PC-fired unit could, therefore, produce up to 40 MW of renewable energy with biomass co-firing. The generating plant may experience a net capacity de-rating whenever biomass is co-fired. This potential reduction in net plant output may be attributed to reduced boiler efficiency and additional auxiliary power requirements. Biomass fuel handling related auxiliary power requirements are dependent upon the form in which biomass is delivered to the plant. Preparation of woody biomass for co-firing in large PC-fired boilers is typically performed onsite with hammer mills or by off-site processing. For an 800 MW unit, onsite fuel size reduction will usually result in an incremental increase in auxiliary power of 3–4 MW, whereas the use of pre-processed biomass such as wood pellets will require a minimal increase in parasitic load. However, delivered fuel costs for raw wood requiring onsite processing are at least 60% lower than that of densified biomass on a heat input basis. This paper includes an economic comparison of co-firing woody biomass that is processed onsite by direct injection vs. co-firing densified woody biomass by co-milling in a large PC-fired boiler. This comparison will consider delivered fuel costs, capital costs, CO2 emissions and impacts upon boiler efficiency and net heat rate.
APA, Harvard, Vancouver, ISO, and other styles
2

Ito, Hiroyuki, Yuto Sakai, Tamio Ida, Yuji Nakamura, and Osamu Fujita. "Combustion of Bio-Coke (Highly Densified Biomass Fuel) Block in High-Temperature Air Flow." In ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44145.

Full text
Abstract:
Bio-coke (BIC, highly densified biomass briquette), a newly developed biomass fuel as an alternative to coal coke which utilized in blast furnace, is employed in this study. This fuel is manufactured in highly compressed and moderate temperature conditions and has advantages in its versatility of biomass resources, high volumetric calorific value and high mechanical strength. Japanese knotweed is chosen as a biomass resource and is shaped into cylinder (48 mm in diameter and 85 mm in length). One of the most important characteristics of BIC is its high apparent density (1300 kg/m3; twice or more than that of an ordinary wood pellet). In the present study, combustion characteristics of a single BIC fuel in high temperature air flow (473–873 K, 550–750 NL/min.) are investigated. Air is preheated and blown to the bottom surface of the BIC. Ignition and subsequent combustion behavior are observed with monitoring gas temperature near the BIC, surface and inside the BIC temperature, and time dependent mass loss of the BIC is measured. In the case with low air temperature, low heat flux from the fuel surface leads to the broad temperature distribution inside the BIC accompanied by the increase in ignition delay time and, then, once ignition takes place degradation rate becomes larger than the case with high temperature air. On the other hand, mass loss rate for the case of solid surface combustion in the high temperature air does not depend on the air temperature but does depend on the air flow rate, which is a result of reduced degradation rate relating to narrow temperature distribution in depth caused by short ignition delay time. Consequently, it is suggested that the history of preheating, i.e. the preheated condition which is determined by air temperature and air flow rate, is an essential factor to determine the ignition mode in the early stage of BIC combustion and the mass burning velocity in the period of main combustion with flame. It is found that the mass loss rate of BIC in the gas-phase combustion period increases with decrease in supplied air temperature in this study.
APA, Harvard, Vancouver, ISO, and other styles
3

Salomón, Marianne, María F. Gómez, James Spelling, and Andrew Martin. "Optimization of a Sawmill-Based Polygeneration Plant." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95844.

Full text
Abstract:
Biomass-based fuels have attracted worldwide interest due to their plentiful supply and their environmentally friendly characteristics. In many cases they are still considered waste but for most industries in Sweden, biomass has changed from being simply a disposal problem to become an important part of the energy supply, thanks to the long-term efforts made by the government, researchers and industry, where energy policies have played an important role. However, the amount of power that could be generated from biomass resources is much greater than that which is currently used. To effectively capture this resource requires a new generation of biomass power plants and their effective integration into already existing industrial processes. The implementation of an integrated polygeneration scheme requires the simultaneous consideration of technical, economic and environmental factors to find optimum solutions. With this in mind, a unified modeling approach that takes into account thermodynamic as well as economic and environmental aspects was used. The analysis was done using ASPEN Utilities and the MATLAB optimization toolbox. A specific case of a sawmill in Sweden, with an annual capacity of 130’000 m3 of sawn wood, has been analyzed and different options for generating electricity and process heat (for the sawmill and for a district heating network) as well as densified biofuels was analyzed. Optimization was then applied for different configurations and operational parameters. The results show that the sawmill has the capability to not only supply its own energy needs, but also to export from 0.4 to 1MW of electricity to the grid, contribute 5 to 6 MWth of district heating and 20 000 ton/y of biomass pellets. The production of pellets helps to maintain the electricity production throughout the year when the district heating demand is lower. However, the levelized electricity cost is higher than the usual electricity price in the Nordic electricity market and may have difficulty to competing with low-cost electricity sources, such as nuclear energy and hydropower. In spite of this, polygeneration remains attractive for covering the energy demands of the sawmill and pelletization plant.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Densified wood' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography