Littérature scientifique sur le sujet « Thermo-wood »
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Articles de revues sur le sujet "Thermo-wood"
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Birkinshaw, C., M. Buggy et A. Carew. « Thermo-mechanical behaviour of wood and wood products ». Journal of Materials Science 24, no 1 (janvier 1989) : 359–62. http://dx.doi.org/10.1007/bf00660981.
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Laskowska, Agnieszka. « Impact of cyclic densification on bending strength and modulus of elasticity of wood from temperate and tropical zones ». BioResources 15, no 2 (9 mars 2020) : 2869–81. http://dx.doi.org/10.15376/biores.15.2.2869-2881.
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Oak (Quercus robur L.), iroko (Milicia excelsa (Welw.) C.C. Berg), and tauari (Couratari spp.) wood were subjected to cyclic thermo-mechanical treatment (CTMT). The densification temperature amounted to 100 °C or 150 °C. The greatest changes in the modulus of rupture (MOR) value of the iroko wood, depending on the number of thermo-mechanical modification cycles, were noted. The MOR of the iroko wood, densified at 100 °C or 150 °C, after second thermo-mechanical modification cycle was twice as high as before the modification. No significant differences were observed between the modulus of elasticity (MOE) of oak wood before and after one modification cycle. Similar dependencies were noted in iroko wood. The thermo-mechanical modification performed over two cycles led to the highest increase, by about 56%, in MOE in oak wood densified at 150 °C. It was demonstrated that modification at 150 °C had a negative impact on iroko wood, which was manifested in the lower compression ratio of iroko at 150 °C than at 100 °C.
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Sandberg, Dick, Peer Haller et Parviz Navi. « Thermo-hydro and thermo-hydro-mechanical wood processing : An opportunity for future environmentally friendly wood products ». Wood Material Science and Engineering 8, no 1 (mars 2013) : 64–88. http://dx.doi.org/10.1080/17480272.2012.751935.
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Chen, Hongyan, Mohsen Bahmani, Miha Humar et Dali Cheng. « Properties of Wood Ceramics Prepared from Thermo-Modified Poplar ». Forests 11, no 11 (16 novembre 2020) : 1204. http://dx.doi.org/10.3390/f11111204.
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Wood ceramics (WCS) were prepared from thermo-modified poplar wood residues and untreated poplar wood. At 1000 °C sintering temperature, the ratios of wood powder and phenolic resin at 10:3, 10:6 and 10:9 were tested. The effects of materials on the properties of WCS, carbon yield and volume shrinkage were studied. With the increase in resin content, the carbon yield increased; however, the volume shrinkage decreased. Carbon yield of WCS made from 220 °C thermo-modified poplar wood was 40.45%, as the ratio of wood powder/phenolic resins was 10:6. The microstructure, chemical structure and crystallinity of WCS were analysed by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD), respectively. The results showed that WCS had a porous structure. WCS prepared from thermo-modified materials, amorphous carbon and hard glass carbon melted more evenly; meanwhile, there were more pores on glass carbon. The FTIR spectra showed that the stretching vibration of C-O-C weakened at ceramics made of thermo-modified poplar. The XRD pattern indicated that the raw material has no apparent influence on the graphitization degree of WCS.
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Fleischhauer, Robert, Jens U. Hartig, Peer Haller et Michael Kaliske. « Moisture-dependent thermo-mechanical constitutive modeling of wood ». Engineering Computations 36, no 1 (19 novembre 2018) : 2–24. http://dx.doi.org/10.1108/ec-09-2017-0368.
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PurposeThe purpose of this study is the numerical investigation of densification and molding processes of wood. Providing theoretical and numerical approaches with respect to a consistent multi-physical finite element method framework are further goals of this research.Design/methodology/approachConstitutive phenomenological descriptions of the thermo-mechanical and moisture-dependent material characteristics of wood are introduced. Special focus is given to a consistent hygro-thermo-mechanical modeling at finite deformations to capture the realistic material behavior of wood, especially when it is subjected to densification and molding processes.FindingsRealistic theoretical formulations of different hygro-thermo-mechanical processes are provided. A successful numerical modeling is demonstrated for beech wood by validation at experimental findings.Originality/valueThe constitutive laws and numerical findings are new, as they govern a multi-physical large deformation framework and are applied to the advanced technology of densification and molding of wood.
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Navi, Parviz, et Fred Girardet. « Effects of Thermo-Hydro-Mechanical Treatment on the Structure and Properties of Wood ». Holzforschung 54, no 3 (13 avril 2000) : 287–93. http://dx.doi.org/10.1515/hf.2000.048.
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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.
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Khezami, Lotfi, Aissa Ould-Dris et Richard Capart. « Activated carbon from thermo-compressed wood and other lignocellulosic precursors ». BioResources 2, no 2 (15 avril 2007) : 193–209. http://dx.doi.org/10.15376/biores.2.2.193-209.
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The effects of thermo-compression on the physical properties such as bulk density, mass yield, surface area, and also adsorption capacity of activated carbon were studied. The activated carbon samples were prepared from thermo-compressed and virgin fir-wood by two methods, a physical activation with CO2 and a chemical activation with KOH. A preliminary thermo-compression method seems an easy way to confer to a tender wood a bulk density almost three times larger than its initial density. Thermo-compression increased yield regardless of the mode of activation. The physical activation caused structural alteration, which enhanced the enlargement of micropores and even their degradation, leading to the formation of mesopores. Chemical activation conferred to activated carbon a heterogeneous and exclusively microporous nature. Moreover, when coupled to chemical activation, thermo-compression resulted in a satisfactory yield (23%), a high surface area (>1700 m2.g-1), and a good adsorption capacity for two model pollutants in aqueous solution: methylene blue and phenol. Activated carbon prepared from thermo-compressed wood exhibited a higher adsorption capacity for both the pollutants than did a commercial activated carbon.
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Tabari, Hassan Ziaei, Fateme Rafiee, Habibolah Khademi-Eslam et Mohammad Pourbakhsh. « Thermo-Chemical Evaluation of Wood Plastic Nanocomposite ». Advanced Materials Research 463-464 (février 2012) : 565–69. http://dx.doi.org/10.4028/www.scientific.net/amr.463-464.565.
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Most applications expose the materials to wide range of temperatures, which may influence on thermal behavior of materials. Thermal degradation of wood polymer composites (WPCs) is a crucial aspect for application and manufacturing process of these products. In this research, wood polymer composites with different nanoclay contents were prepared by melts compounding method. The amount of wood flour and coupling agent were fixed at 40% and 10% wt% (total weight), respectively, and the different levels of nanoclay include 0, 3 and 5% wt% were used in preparing the composites. Thermal properties of nanocomposites were characterized by Differential Scanning Calorimeter (DSC) and thermal gravimetric analysis (TGA). The DSC analyses show that the crystallization temperature (Tc), enthalpy ΔHm, and the degree of crystallinity (Xc) of the nanocomposites were increased by addition of nanoclay. The TGA results indicate that by increasing the nanoclay percentage the degradation temperatures and thermal stability was enhanced.
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de Lima, Nídia Niela, Vinícius Resende de Castro, Nayara Franzini Lopes, Ítalo Lima Nunes, Frances Alves Andrade, Antonio José Vinha Zanuncio, Angélica de Cassia Oliveira Carneiro et Solange Araújo. « Tannin extracts as a preservative for pine thermo-mechanically densified wood ». BioResources 18, no 1 (22 novembre 2022) : 641–52. http://dx.doi.org/10.15376/biores.18.1.641-652.
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Thermo-mechanical densification modifies wood to produce a more dense and resistant lignocellulosic material and may degrade extractives that contribute to the increased susceptibility of wood to attack by xylophagous organisms. This study evaluated the efficiency of tannin extracts of Acacia mearnsii in the treatment of thermo-mechanical densified pine wood in relation to physical, mechanical, and biological resistance (Cryptotermes brevis) properties. Pinus elliottii samples were pretreated with oxalic acid in a Parr reactor, then treated by diffusion in tannin solutions at concentrations 5, 10, and 15%, and finally hot pressed. The apparent density of the modified wood was 87.8% greater than that of the in natura wood (control) with tannins at 15%. The mechanical strength increased, especially the parallel compressive strength, which had an average increase of 169% for the wood with tannins at 10 and 15%, compared with the in natura wood. There was an increase in termite mortality and a reduction in damage for the modified wood treated with 15% tannins, obtaining the best results in mechanical and biological resistance and for the physical parameters. Thermal densification pine wood and preserved with tannin extractives proved to be a potential alternative as a high performance material.
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Tuyen, Nguyen Thi, Pham Van Chuong et Vu Kim Dung, al. et. « Resistance of Cunninghamia lanceolata Wood Against White-rot Fungi by Using Thermo-Mechanical Treatment ». Journal of Agriculture and Crops, no 92 (1 mars 2023) : 178–86. http://dx.doi.org/10.32861/jac.92.178.186.
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Heat treatment is an effective method to enhance the biological durability of wood without the use of preservatives. This study aims to analyze the effect of thermo-mechanical treatment on the durability of wood against the attack of some white rot fungi. The central composite design (CCD) method with the help of Design Expert 12.0 software was used to investigate the effects of temperature, compression time, and compression ratio on the white rot fungus resistance of Cunninghamia lanceolata wood. The obtained results revealed that the thermo-mechanical treatment of Cunninghamia lanceolata samples showed improved antifungal resistance compared to the untreated ones. After 4 months of testing in laboratory conditions, all wood samples with heat-mechanical treatment showed better resistance to fungi. Moreover, the different temperatures, compression ratios, and compression time bring out the different mass loss rates. The obtained results indicate that the wood samples modified at the temperature of 200°C, and 0.6 min/mm thickness combined with the compression ratio ranging from 40÷42% gave the lowest loss rate. Particularly, the resistance test for Lentinula edodes gives the best results when the wood compression time is at 0.7 min/mm thickness. Also, this work would provide a scientific and theoretical basis for the relationship between thermo-mechanical treatment and the biological durability of Cunninghamia lanceolata wood.
Thèses sur le sujet "Thermo-wood"
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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.
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Bhattacharjee, Sujal. « Impact of Recycling on the Mechanical and Thermo-Mechanical Properties of Wood Flour/High Density Polyethylene and Wood Flour/Poly Lactic Acid Composites ». Thesis, North Dakota State University, 2016. https://hdl.handle.net/10365/28285.
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This research concentrates on the recyclability of two wood plastic composites (WPCs) - wood flour/HDPE and wood flour/PLA composites. Two different filler loadings (30 and 50 wt%) were considered for each polymer composite. Each composite formulation contained 3 wt% of a coupling agent, and was individually recycled up to six times by extrusion process. Samples for mechanical and thermo-mechanical tests were prepared by injection molding. All test results were statistically analyzed with a confidence level of 95%. Additional tests such as fiber length measurement, GPC, DSC, TGA, FTIR, and SEM were also performed at specific reprocessing cycles. After reprocessing six times, all formulations showed lower relative decrease in most stiffness properties but higher relative increase in most strain properties. In strength properties, both HDPE composites showed lower relative decrease after reprocessed six times; however, higher and lower filler PLA composites showed sharp decrease reprocessed at second and six times respectively.
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Froidevaux, Julien. « Wood and paint layers aging and risk analysis of ancient panel painting ». Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20032/document.
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Les anciennes peintures sur bois représentent une part importante du patrimoine culturel européen. Depuis longtemps, il est connu que les conditions de stockage peuvent entraîner des dégradations et endommagements aux panneaux. Une bonne compréhension de l'état actuel des peintures sur bois ainsi que la prédiction de leur comportement dans diverses conditions climatiques est essentielle pour mieux les conserver et les restaurer. De telles analyses peuvent être faites par le biais de la modélisation numérique. Cependant, la modélisation numérique est efficace que si les paramètres des matériaux sont équivalents à ceux de la réalité. Dans ce travail, les modifications mécaniques, physiques et chimiques qui se produisent au cours du vieillissement naturel ont été étudiées pour le bois et les couches de peintures. Les possibilités d'accélérer le vieillissement par des traitements thermo-hydrique ont été appliquées avec succès au bois. Une loi de vieillissement du bois a été trouvée pour la résistance radiale et la luminosité de la couleur. Malheureusement, une tel loi n'a pas été trouvé pour les couches de peinture. Ensuite, un modèle numérique tridimensionnel sur le comportement hygroscopique et mécanique des panneaux peints a été développé. La comparaison entre ce modèle et des expériences sont en bon accord. Finalement, une analyse de risques sur une ancienne peinture a montré que des fluctuations d'humidité relative normales ne devraient pas promouvoir de dommages dans le support en bois, mais la fissuration de la couche picturale est possibleAncient wood panel paintings represent an important part of the European cultural heritage. Since long time it is known that the storing condition can degrade and damage them. Understanding of the actual state of old panel paintings and the prediction of their behaviour under various climatic conditions is essential to better conserve and restore them. Such analysis could be done by numerical modelling. However, numerical modelling can achieved good predictions only if the materials parameters are adequately determined. In this work, the mechanical, physical and chemical modifications occurring during natural aging have been investigated for wood and paint layers. The possibility to accelerate the aging with thermo-hydro treatments has been successfully applied to wood. A wood aging law has been found for the radial strength and the lightness. Unfortunately, no such law has been found for the paint layers. The hygroscopic and mechanical behaviour of panel paintings has been then simulated in 3D by finite element method model including time dependent behaviour. The comparison between the model and experiments shows good agreement. Finally, risk analysis on an old painting shows that normal climate fluctuation should not promote cracks in the wooden support but the cracking of the ground layer is possible
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Akkaoui, Abdessamad. « Bétons de granulats de bois : étude expérimentale et théorique des propriétés thermo-hydro-mécaniques par des approches multi-échelles ». Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1169/document.
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Les bétons végétaux, composés de particules végétales et d'un liant minéral ou organique, constituent une solution à explorer pour limiter l'impact environnemental du bâtiment. Utilisés principalement pour leurs performances thermiques, ces matériaux suscitent l'intérêt de plusieurs organismes de recherche ainsi que de plusieurs entreprises industrielles. La généralisation de leur utilisation dans la construction ne sera pas possible sans résoudre certains problèmes liés à leurs techniques de mise en œuvre, à leur certification et à leur durabilité. Le présent travail a pour objectif de contribuer à la caractérisation de ces matériaux complexes. Il s'agit en particulier d'étudier les comportements mécanique, thermique et hydromécanique du béton de granulats de bois. La stratégie utilisée consiste à combiner l'expérience et la modélisation pour mieux comprendre les mécanismes mis en jeu. Le module de Young et la résistance en compression ont été mesurés expérimentalement à l'aide de la technique de corrélation d'images numériques. L'évolution de ces propriétés dépend des conditions de conservation, de la durée de séchage ainsi que de la teneur en ciment. En raison de l'orientation aléatoire des granulats de bois, le comportement mécanique du béton est isotrope. Un modèle d'homogénéisation basé sur le schéma autocohérent a été développé pour prédire le module de Young du béton et ses résultats sont très satisfaisants. Les mesures de la conductivité thermique montrent que celle-ci reste constante en conditions endogènes. La modélisation de cette propriété par le schéma autocohérent conduit à des résultats cohérents avec les mesures expérimentales. En conditions de dessiccation, la conductivité thermique dépend linéairement de la densité du béton. L'évolution de la conductivité thermique des granulats de bois et de la pâte de ciment au cours du séchage a été modélisée grâce au schéma de Mori-Tanaka. Ces évolutions ont été intégrées dans le modèle autocohérent qui fournit ainsi des résultats satisfaisants, mais qui pourrait être amélioré si l'on disposait des courbes de sorption/désorption des constituants du béton. Les variations dimensionnelles du béton au cours du temps dépendent des conditions de conservation, mais pas de la direction de mesure, ni de la teneur en ciment. Un modèle reposant sur une combinaison des déformations induites par la désorption de l'eau par des constituants et le transfert d'humidité entre ceux-ci a été proposé et a permis de capturer les tendances des déformations du béton sauf au jeune âge. À l'échelle locale, l'étude a montré que les déformations du béton sont du même ordre de grandeur que celles de la pâte de ciment. Elle a aussi mis en évidence un endommagement partiel de l'interface granulat/liant qui mériterait à être pris en compte dans la modélisationEnvironmentally-friendly concretes, made up of plant-based particles and mineral or organic binder, are solutions worth exploring to reduce the environmental impact of buildings. Mainly used for their thermal performance, these materials have aroused interest of many research organisations and industrial companies. Their widespread use in construction is not possible without resolving some technical problems related to their implementation, certification and durability. This work aims to contribute to characterize these complex materials, in particular to study the mechanical, thermal and hydromechanical behaviors of wood-aggregate concrete. Modeling and experiments have been used to understand the complex mechanisms involved. The Young's modulus and the compressive strength were experimentally measured using digital image correlation. The evolution of these properties depends on the conditions of storage, the drying time and the cement content. Because of the random orientation of the wood aggregates, the material exhibits isotropic behavior. A homogenization model based on a self-consistent scheme was developed to predict the Young's modulus. The results were satisfactory. Measurements show that thermal conductivity remains constant under sealed conditions. The modeling of this property with the self-consistent scheme gives results consistent with experimental measurements. In desiccation conditions, the thermal conductivity depends linearly on the density of concrete. The evolution of the thermal conductivity of the wood aggregates and the cement paste during drying was modeled with the Mori-Tanaka scheme. These evolutions were integrated into the self-consistent model, which yielded satisfactory results, but could be improved if sorption/desorption curves of the phases were available. The macroscopic dimensional variations of the wood-aggregate concretes depended on the storage conditions, but not on the measurement direction, nor on the cement content. A model based on the combination of the strains induced by the desorption of water from the phases and the moisture transfer between them was proposed. It allowed us to capture the trends of the strains of our concrete except at early age. At a local scale, the study showed that the strains of concrete were close to those of the cement paste. The study also shed light on a significant damage of the aggregate/binder interfaces, which would deserve to be taken into account into the modeling
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Hamada, Joël. « Effet de la variabilité intra et interspécifique du bois sur les procédés de traitement thermique ». Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0254/document.
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Dans le contexte du développement durable qui a vu l’introduction de la directive produits biocides BPD 98/8/CE, l’étude des méthodes innovantes de préservation du bois comme le traitement thermique revêt une importance prépondérante. Le traitement thermique du bois permet d’améliorer ses propriétés de résistance biologique, de stabilité dimensionnelle ainsi que son aspect esthétique, sans ajout de produit chimique. Les études actuelles sur la problématique de la qualité du bois traité thermiquement se focalisent sur les caractéristiques finales du bois déjà traité, l’influence des conditions de traitement ou encore l’effet essence. Les propriétés intrinsèques du bois avant le traitement ne sont pas encore prises en compte. Les propriétés du bois telles que la densité ou la composition chimique étant variables principalement sous l’effet de l’activité humaine comme la sylviculture, l’objectif de cette thèse était d’évaluer l’impact de cette variabilité chez le chêne sessile (Quercus petraea Liebll.) et le sapin (Abies alba Mill) sur leur modification par voie thermique. Un scanner et un micro-densitomètre à rayons X ont été utilisés pour caractériser la variation de la densité des échantillons de planches et des cernes de croissance provenant des arbres étudiés. Des traitements thermiques ont été réalisés dans un four pilote à conduction sous vide de type macro-thermobalance et un analyseur thermogravimétrique (ATG). Des analyses chimiques ont été également réalisées. Les résultats montrent qu’en prenant la perte de masse due à la dégradation thermique du bois comme réponse, les types de tissus du bois et la composition chimique influencent sa thermo-dégradation. Que ce soit chez Quercus petraea ou chez Abies alba, le bois de printemps était plus sensible au traitement thermique que son voisin de bois d’été. De plus, les portions radiales du tronc, du bois juvénile à l’aubier en passant par le bois mature, se dégradaient suivant des cinétiques différentes. En conclusion, la variation de la microstructure et la composition chimique de ces bois influencent leur cinétique globale de thermo-dégradation. La sylviculture impacte cette différence intraspécifique de cinétique de dégradation à l’échelle intra- et interarbre. En effet, dans le cas du sapin pectiné, une gestion très dynamique des forêts dans le but de stimuler la croissance rapide des arbres qui produisent de gros bois contenant des cernes très larges, est source de variation dans la structure anatomique et la composition chimique à l’intérieur des arbres en comparaison aux petits bois à croissance lente plus homogènes. Toutes ces analyses ont pour objectif final de comprendre le lien entre les propriétés initiales du bois et les modifications thermiques intervenant au cours du traitement afin d’apporter une information utile aux industriels lors du choix des pièces de bois destinées au traitement thermique en vue d’une amélioration de la qualité du bois traité thermiquementIn the context of sustainable development which has seen the introduction of the biocides directive BPD 98/8/CE in the EU, innovative wood preservation practices such as Heat Treatment (HT) become relevant. Wood HT, also termed wood thermal modification, is a physical modification technology by which wood is heated at around 200 °C in an inert atmosphere. The main purpose of the treatment is to improve the biological durability and dimensional stability of wood. Current studies on thermally modified wood (TMW) quality are focusing on treated material, on treatment conditions or on species effect on the end-product characteristics. Relatively little is known about the effect of intrinsic wood properties on its thermal modification. As wood properties vary especially under the influence of human activities through sylviculture, this thesis studied the effect of European oak and silver fir wood density and chemical composition on their thermal modification kinetic. An X rays computed tomography (CT) and densitometer were used to characterize wood samples. Boards were heat-treated by conduction under vacuum using a pilot furnace, whereas sawdust samples underwent thermo-gravimetric analysis under nitrogen. The analysis allowed finding intra- and interspecific variations, especially within growth rings and along radial direction (from pith to bark). Forest management impacted heat modification kinetic of the studied samples, especially in silver fir where fast grown wood was more sensitive to treatment. The finding will be used as additional information to the wood industry which will account for homogeneity of loadings destined to heat treatment
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Mubarok, Mahdi. « Valorization of beech wood through development of innovative and environmentally friendly chemical modification treatments ». Electronic Thesis or Diss., Université de Lorraine, 2019. http://www.theses.fr/2019LORR0141.
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Dans cette étude, l’amélioration des propriétés physiques et de sa durabilité aux agents de dégradation biologique du hêtre européen (Fagus sylvatica) a été réalisée au moyen de différents traitements. Les premiers types de traitements sont basés sur l'imprégnation de dérivés vinyliques de glycérol ou de polyglycérol en tant qu'additif suivi d’une étape de modification thermique réalisée dans un réacteur ouvert (OHT) ou fermé (HPS). Le deuxième type de traitement repose sur la poly-estérification in situ du sorbitol et de l'acide citrique à différentes concentrations et températures de durcissement en système ouvert. Diverses propriétés de durabilité physique, chimique, mécanique et biologique des bois modifiés ont été évaluées. Les résultats montrent que certains traitements peuvent améliorer de manière significative les propriétés de durabilité physique et biologique du bois contre les agents de pourriture blanche, brune et molle et surtout vis-à-vis de l’attaque des termites comparativement au bois non traité ou modifié thermiquement uniquementIn this study, improvement of physical and biological durability properties of European beech (Fagus sylvatica) has been performed through different bulking impregnation treatments. The first modification was based on the impregnation of vinylic derivatives of glycerol or polyglycerol as additive followed with different thermal modification conditions in the opened system (OHT) or in the closed system (HPS). The second modification was based on the in-situ polyesterification of sorbitol and citric acid at different concentrations and curing temperatures in the opened system. Various physical, chemical, mechanical, and biological durability properties of the modified woods were evaluated, including certain properties during modification. The results have disclosed that certain treatments can improve significantly physical and biological durability properties of wood against decay (white rot, brown rot, and soft rot fungi) and termites attacks in comparison to untreated wood or thermally modified woods
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Archila, Santos Hector Fabio. « Thermo-hydro-mechanically modified cross-laminated Guadua-bamboo panels ». Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.675700.
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Guadua angustifolia Kunth (Guadua) is a bamboo species native to South and Central America that has been widely used for structural applications in small and large-scale buildings, bridges and temporary structures. Currently, its structural use is regulated within seismic resistant building codes in countries such as Peru and Colombia. Nevertheless, Guadua remains a material for vernacular construction associated with high levels of manual labour and structural unpredictability. Guadua buildings are limited to two storeys due to the overall flexibility of the slender and hollow culms and its connection systems. Its axial specific stiffness is comparable to that of steel and hardwoods, but unlike wood, Guadua’s hollow structure and lack of ray cells render it prone to buckling along the grain and to transverse crushing. As a result, Guadua’s mainstream use in construction and transformation into standard sizes or engineered Guadua products is scarce. Therefore, this work focussed on the development of standardised flat industrial structural products from Guadua devising replicable manufacturing technologies and engineering methods to measure and predict their mechanical behaviour. Cross-laminated Guadua panels were developed using thermohydro-mechanically modified and laminated flat Guadua strips glued with a high performance resin. Guadua was subjected to thermo-hydro-mechanical (THM) treatments that modified its microstructure and mechanical properties. THM treatment was applied to Guadua with the aim of tackling the difficulties in the fabrication of standardised construction materials and to gain a uniform fibre content profile that facilitated prediction of mechanical properties for structural design. Densified homogenous flat Guadua strips (FGS) were obtained. Elastic properties of FGS were determined in tension, compression and shear using small-clear specimens. These properties were used to predict the structural behaviour of G-XLam panels comprised of three and five layers (G-XLam3 and G-XLam5) by numerical methods. The panels were assumed as multi-layered systems composed of contiguous lamellas with orthotropic axes orientated at 0º and 90º. A finite element (FE) model was developed, and successfully simulated the response of G-XLam3 & 5 panels virtually loaded with the same boundary conditions as the following experimental tests on full-scale panels. G-XLam3 and G-XLam5 were manufactured and their mechanical properties evaluated by testing large specimens in compression, shear and bending. Results from numerical, FE predictions and mechanical testing demonstrated comparable results. Finally, design and manufacturing aspects of the G-XLam panels were discussed and examples of their architectural and structural use in construction applications such as mid-rise buildings, grid shells and vaults are presented. Overall, this research studies THM treatments applied to Guadua in order to produce standardised engineered Guadua products (EGP), and provides guidelines for manufacturing, testing, and for the structural analysis and design with G-XLam panels. These factors are of key importance for the use of Guadua as a mainstream material in construction.
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Gade, Prabhavathi. « Investigation of Volatile Products from Wood Pyrolysis ». TopSCHOLAR®, 2010. http://digitalcommons.wku.edu/theses/1076.
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In this research we are following the thermo-chemical degradation of wood in the absence of oxygen. The objectives are to evaluate the influence of heating rates on pyrolysis products obtained from wood pyrolysis and to evaluate the influence of acid pre-treatment on pyrolysis products. Depending on the wood heating rates, pyrolysis can be categorized as Flash pyrolysis, Fast pyrolysis, and Slow pyrolysis. We have evaluated the volatile products obtained at different heating rates and the volatile products obtained from sulfuric acid pre-treatment by using gas chromatography- mass spectrometry (GC-MS). We have also performed thermo-gravimetric analysis (TGA) of raw wood samples and sulfuric acid pre-treated wood samples of Yellow Pine to determine the changes in weight in relation to change in temperature.
Our results indicated that by using the Flash, Fast, and Slow heating rates, the overall volatile products obtained from wood pyrolysis (i.e. the overall list of all the compounds obtained from different temperature ranges in wood pyrolysis by using different heating rates) were the same, but the volatile products obtained at different temperature ranges like Room temperature-300°C, 300°C - 400°C, and 400°C -500°C in Flash, Fast, and Slow pyrolysis were different. Most of the volatile products obtained from the pyrolysis of untreated wood were phenols. Our results also indicated that the pretreatment of wood with sulfuric acid alters the charcoal properties and releases gaseous products including furan derivatives that are useful as fuels or fuel additives. The sulfuric acid (10%) pretreatment of wood followed by slow pyrolysis produced maximum yield of charcoal, indicated by the lowest mass % decrease of 58.234. The production of furan derivatives increased by using sulfuric acid pre-treatment, which is a good improvement for the production of Furanics, the furan based biofuels. The furan based biofuels are of increasing research interest because of their significant advantages over the first generation biofuels. The thermogravimetric analysis (TGA) results indicated that the acid pre-treatment altered the decomposition rate of pyrolysis and lowered the onset of temperature for decomposition.
The use of thermal degradation of plants for creating chemicals and fuels is seeing renewed interest across the globe as it is considered carbon-neutral and it uses a renewable feedstock. The information obtained from this research work will also be valued by industries, such as charcoal and activated carbon producers, which currently perform biomass pyrolysis, by allowing them to form approaches that optimize their energy use and minimize waste.
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Tita, Bertrand Asongwe. « Waste-to-Energy : A study on Reaction Kinetics of Tropical Wood Sawdust ». Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-9746.
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The reaction kinetics of Iroko and Mahogany were studied using TGA. The pyrolysis process was achieved using six different heating rates of 2,5,8,12,15 and 20˚C. A 15˚C/min heating rate was used for gasification in steam at different temperatures while varying the concentrations of nitrogen and steam in the process. The kinetic parameters, activation energy and pre exponential factor, were obtained by implementing two chosen kinetic models. These models are: Friedman’s Iso-conversional Method, Flynn-Wall-Ozawa Method (FWO). There were substantial differences in the values of the kinetic triplets found from the experiments. Due to the substantial differences in the values, it was not the best way to perform this kind of analysis (which is the traditional way) but instead to use pure regression analysis; but using it for the whole data set (that means for all heating rates) and minimize the difference with experimental data.
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Elias, Robert M. « The chemical reactivity of thermo mechanical pulp (TMP) fibres : a detailed kinetic study of the reaction between fibre and isolated fractions of hollcellulose and cellulose with succinic anhydride ». Thesis, Bangor University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239884.
Texte intégralLivres sur le sujet "Thermo-wood"
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Navi, Parvis, et Dick Sandberg. Thermo-Hydro-Mechanical Wood Processing. Taylor & Francis Group, 2012.
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Navi, Parvis, et Dick Sandberg. Thermo-Hydro-Mechanical Wood Processing. Taylor & Francis Group, 2012.
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Fuller, James J. Predicting the thermo-mechanical behavior of a gypsum-to-wood nailed connection. 1990.
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Fuller, James J. Predicting the thermo-mechanical behavior of a gypsum-to-wood nailed connection. 1990.
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Ren, Shan. Thermo-hygro rheological behavior of materials used in the manufacture of wood-based composites. 1991.
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Ren, Shan. Thermo-hygro rheological behavior of materials used in the manufacture of wood-based composites. 1991.
Trouver le texte intégralChapitres de livres sur le sujet "Thermo-wood"
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Huet, Christian. « Physical Bases for the Thermo-Hygro-Rheological Behaviours of Wood in Finite Deformations ». Dans Large Deformations of Solids : Physical Basis and Mathematical Modelling, 409–32. Dordrecht : Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-3407-8_22.
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Blackadder, William, et Erik Rensfelt. « A Pressurized Thermo Balance for Pyrolysis and Gasification Studies of Biomass, Wood and Peat ». Dans Fundamentals of Thermochemical Biomass Conversion, 747–59. Dordrecht : Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-4932-4_39.
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Tran, Trong Tuan, Pierre Girods, Mourad Khelifa, Marc Oudjene et Yann Rogaume. « Characterization of Kinetics of Thermal Decomposition of Densified Wood Materials from Isothermal Thermo-Gravimetric Experiments ». Dans Advances in Mechanical Engineering and Mechanics II, 401–9. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-86446-0_53.
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Fleischhauer, Robert, et Michael Kaliske. « Hygro- and Thermo-Mechanical Modeling of Wood at Large Deformations : Application to Densification and Forming of Wooden Structures ». Dans Advanced Structured Materials, 59–97. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-70563-7_4.
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Bajwa, Dilpreet S., et Sujal Bhattacharjee. « Impact of Recycling on the Mechanical and Thermo-Mechanical Properties of Wood Fiber Based HDPE and PLA Composites ». Dans Handbook of Composites from Renewable Materials, 271–91. Hoboken, NJ, USA : John Wiley & Sons, Inc., 2017. http://dx.doi.org/10.1002/9781119441632.ch50.
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« Wood Bending ». Dans Thermo-Hydro-Mechanical Wood Processing. EFPL Press, 2012. http://dx.doi.org/10.1201/b10143-11.
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« Reconstituted wood ». Dans Thermo-Hydro-Mechanical Wood Processing. EFPL Press, 2012. http://dx.doi.org/10.1201/b10143-12.
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« Wood Modification ». Dans Thermo-Hydro-Mechanical Wood Processing. EFPL Press, 2012. http://dx.doi.org/10.1201/b10143-2.
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« Wood welding ». Dans Thermo-Hydro-Mechanical Wood Processing. EFPL Press, 2012. http://dx.doi.org/10.1201/b10143-8.
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« Elasto-viscoplasticity of wood ». Dans Thermo-Hydro-Mechanical Wood Processing. EFPL Press, 2012. http://dx.doi.org/10.1201/b10143-5.
Texte intégralActes de conférences sur le sujet "Thermo-wood"
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Derome, Dominique, Alessandra Patera, Ahmad Rafsanjani, Saeed Abbasion et Jan Carmeliet. « The Role of Water in the Hygro-Thermo-Mechanical Behavior of Wood ». Dans ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-65101.
Texte intégralRésumé :
Wood, due to its biological origin, has the capacity to interact with water. Sorption/desorption of moisture is accompanied with swelling/shrinkage and softening/hardening of its stiffness. The correct prediction of the behavior of wood components undergoing environmental loading or industrial process requires that the hygric, thermal and mechanical (HTM) behavior of wood are considered in a coupled manner. In addition, we propose a comprehensive framework using a fully coupled poromechanical approach, where its multiscale implementation provides the capacity to take into account, directly, the exact geometry of wood cellular structure, using computational homogenization. A hierarchical model is used to take into account the subcellular composite-like organization of the material. Such advanced modeling requires high resolution experimental data for the appropriate determination of inputs and for its validation.
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Girişken, Çağla, Ceyda Yanmaz, Buse Nur Can, Yakup Ülçer et Yusuf Ziya Menceloğlu. « Low density, high modulus polypropylene wood composites prepared by using thermo kinetic mixer ». Dans PROCEEDINGS OF THE 35TH INTERNATIONAL CONFERENCE OF THE POLYMER PROCESSING SOCIETY (PPS-35). AIP Publishing, 2020. http://dx.doi.org/10.1063/1.5142935.
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Kou, Nannan, Fu Zhao et Li Zhang. « Aspen Plus Process Simulation of Flexible Feedstock Thermo-Chemical Ethanol Production ». Dans ASME 2009 International Manufacturing Science and Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/msec2009-84090.
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Current US transportation sector mainly relies on liquid hydrocarbon derived from petroleum and about 60% of the petroleum consumed is from areas where supply may be disturbed by regional instability. This has led to serious concerns on global warming and energy security. To address these issues, numerous alternative energy carriers have been proposed. Among them, second generation biofuel is one of the most promising technologies. Gasification based thermo-chemical conversion can utilize a wide range of biomass wastes and residues and bring flexibility to both feedstock and production sides of a plan. Thus it presents an attractive technical route. In this paper, a flexible feedstock thermo-chemical ethanol production process is investigated. This research focuses mainly on the evaluation of the feasibility of the process through numerical simulation. An existing thermo-chemical ethanol production model developed by NREL has been updated to handle the cases when different biomass feedstock and feedstock combinations are used. It is found that the ethanol yield is positively linear proportional to the feedstock feeding rate, while the total conversion efficiency is negatively proportional to the feeding rate. To demonstrate a feedstock management strategy, a plant located near a major city with a population of 200,000 and above is considered and MSW, corn stover and wood chips are selected as potential feedstock. Simulation results indicate that with wood chips as the backup feedstock the plant can be operated under extreme conditions when corn stover availability is significantly reduced without major equipment modification.
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Kou, Nannan, et Fu Zhao. « Investigation of the Feasibility and Feedstock Management Strategies of a Flexible Biomass to Ethanol Plant via Process Simulation ». Dans ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-10494.
Texte intégralRésumé :
Current US transportation sector mainly relies on liquid hydrocarbon derived from petroleum oil and about 60% of the petroleum oil consumed is from areas where supply may be disturbed by regional instability. This has led to serious concerns on global warming and energy security. To address these issues, numerous alternative energy carriers have been proposed. Among them, second generation biofuel is one of the most promising technologies. Gasification based thermo-chemical conversion can utilize a wide range of biomass wastes and residues and bring flexibility to both feedstock and production sides of a plant, thus presents an attractive technical route. In this paper, a flexible feedstock thermo-chemical ethanol production process is investigated. This research focuses mainly on the evaluation of the feasibility of the process through numerical simulation. An existing thermo-chemical ethanol production model developed by NREL has been updated to handle the cases when different biomass feedstock and feedstock combinations are used. It is found that the ethanol yield is positively proportional to the feedstock feeding rate, while the total conversion efficiency is negatively proportional to the feeding rate. To demonstrate a feedstock management strategy, a plant located near a major city with a population of 200,000 and above is considered and MSW, legume straw and wood chips are selected as potential feedstock. Simulation results indicate that with wood chips as the backup feedstock the plant can be operated under extreme conditions when legume straw availability is significantly reduced without major equipment modification.
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Munoz-Hernandez, Andres, et Gerardo Diaz. « Dielectric Breakdown Process for Biomass Gasification ». Dans ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-36402.
Texte intégralRésumé :
When exposed to a sufficiently strong electric field, all materials suffer from a form of breakdown. Although wood is sometimes utilized as an electrical insulator, it is also subject to breakdown when exposed to high electric fields. In general, dielectric breakdown is considered a negative effect for electrically insulating materials since it implies the loss of insulating properties of the material. However, the high temperatures generated inside the material (∼2000 K) can be used as an efficient way to induce the thermo-chemical decomposition of biomass with the purpose of sustainable energy generation. A low power (∼100 W) experimental setup using this novel approach was built to perform experiments under air or nitrogen environments at different flow rates to determine the gasification rate and the specific energy required for thermal-decomposition. Thermal decomposition rates that require specific energies of the order of 17 kJ/g were measured, suggesting that dielectric breakdown can be efficiently used for waste-to-energy conversion.
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Kenarsari, Saeed Danaei, et Yuan Zheng. « A Numerical Study of Fast Pyrolysis of Beetle Killed Pine Trees ». Dans ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62991.
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Since 1990s, as a result of unprecedented drought and warm winters, mountain pine beetles have devastated mature pine trees in the forests of western North America from Mexico to Canada. Especially, in the State of Wyoming, there are more than 1 million acres of dead forest now. These beetle killed trees are a source of wildfire and if left unharvested will decay and release carbon back to the atmosphere. Fast pyrolysis is a promising method to transfer the beetle killed pine trees into bio-oils. In the present study, an unsteady state mathematical model is developed to simulate the fast pyrolysis process, which converts solid pine wood pellets into char (solid), bio-oils (liquid) and gaseous products in the absence of oxidizer in a temperature range from 500°C to 1000°C within short residence time. The main goal of the study is to advance the understanding of kinetics and convective and radiative heat transfer in biomass fast pyrolysis process. Conservation equations of total mass, species, momentum, and energy, coupled with the chemical kinetics model, have been developed and solved numerically to simulate fast pyrolysis of various cylindrical beetle killed pine pellets (10 mm diameter and 3 mm thickness) in a reactor (30 mm inside diameter and 50 mm height) exposed to various radiative heating flux (0.2 MW/m2 to 0.8 MW/m2). A fast pyrolysis kinetics model for pine wood that includes competitive path ways for the formation of solid, liquid, and gaseous products plus secondary reactions of primary products has been adapted. Several heat transfer correlations and thermo property models available in the literature have been evaluated and adapted in the simulation. Finite element method is used to solve the conservation equations and a 4th order Runge-Kutta method is used to solve the chemical kinetics. Unsteady-state two dimensional temperature and product distributions throughout the entire pyrolysis process were simulated and the simulated product yields were compared to the experimental data available in the literature. This study demonstrates the importance of the secondary reactions and appropriate convective and radiative modeling in the numerical simulation of biomass fast pyrolysis.
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Butterman, Heidi C., et Marco J. Castaldi. « CO2 Enhanced Steam Gasification of Biomass Fuels ». Dans 16th Annual North American Waste-to-Energy Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/nawtec16-1949.
Texte intégralRésumé :
The current study involves an experimental investigation of the decomposition of various biomass feedstocks and their conversion to gaseous fuels such as hydrogen. The steam gasification process resulted in higher levels of H2 and CO for various CO2 input ratios. With increasing rates of CO2 introduced into the feed stream, enhanced char conversion and increased CO levels were observed. While CH4 evolution was present throughout the gasification process at consistently low concentrations, H2 evolution was at significantly higher levels though it was detected only at elevated gasification temperatures: above 500°C for the herbaceous and non-wood samples and above 650°C for the wood biomass fuels studied. The biomass feedstocks were studied through the use of Thermo Gravimetric Analysis (TGA), Gas Chromatography, Calorimetry, Atomic Absorption Spectrophotometry (AAS), and the Scanning Electron Microscope with Energy Dispersive X-Ray Analysis (SEM/EDX). The chemical composition of the various biomass fuels and their combustion and gasification ash residues, in addition to the mass decay and gaseous evolution behavior were investigated as a function of temperature. The thermal treatment of biomass fuels involves pyrolysis and gasification with combustion occurring at the higher temperatures. In the gasification environment, when combustion processes are occurring, gaseous components evolve from the fuel and react with oxygen either released from the biomass structure itself, or from the injected steam and CO2. These high temperature reactions are responsible for the enhanced burnout of the carbon (charcoal) structure that is produced during the low temperature pyrolytic breakdown of the biomass. Since the ligno-cellulosic biomass component typically found in U.S. MSW is greater than 50%, techniques to enhance the thermal treatment of biomass feedstocks can also aid in the processing of MSW. Gas evolution as a function of temperature was monitored for H2, CH4, CO2 and CO for several biomass fuels that included woods, grasses and other ligno-cellulosic samples. These included oak, sugar maple, poplar, spruce, white pine, Douglas fir, alfalfa, cordgrass, beachgrass, maple bark, pine needles, blue noble fir needles, pecan shells, almond shells, walnut shells, wheat straw, and green olive pit. The TGA mass decay curves showed similar behavior for the woods, grasses and agricultural residues, where most of the mass loss occurred before 500°C. Most feedstocks exhibited 2 constant mass steps though several exhibited a third with completed mass loss by 900°–1000°C. Two distinct mass decay regimes were found to correlate well with two distinct gas evolution regimes exhibited in the curves for CO, H2 and CH4. Most of the mass loss occurred during pyrolysis, with the remaining degradation to ash or char occurring in the high temperature gasification regime. One characteristic of biomass samples is the highly variable nature of the mineral composition. SEM/EDX analyses indicated high levels of potassium, magnesium and phosphorus in the ash residue. The devitrification and embrittlement of the quartz furnace and balance rods were attributed to the high mineral content of many of the biomass feedstocks, with the high alkaline oxide levels of the grasses being particularly destructive. While mineral content may exert a beneficial effect through enhanced char reactivity with the possibility for a more thorough processing of the feedstock, the potential for corrosion and slagging would necessitate the judicious selection and possible pretreatment of biomass fuels. A major advantage of thermal treatment through gasification prior to combustion is the ability to remove many of the corrosive volatiles and ash elements such as potassium, sodium and chlorine to avert damage to the process equipment.
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Toma, Peter, Karl Miller et J. Mark A. Hoddenbagh. « Reducing the Deposition of Scale in the Evaporator of a Mechanical Vapour Recompression System for Concentration of Pulp Mill Effluents ». Dans ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-39599.
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A numerical model was developed, validated with the aid of pilot evaporator tests, and used to assess practical methods of minimizing scaling observed in a mechanical vapour recompression (MVR) plant at Millar’s Western’s Meadow Lake, Saskatchewan pulp mill. On average, 8,000 m3/day of effluent (approximately 7 m3/Bone Dry Tonne product) resulting from bleached-chemi-thermo-mechanical wood processing, are purified and the recovered water is returned to the plant while the effluent is concentrated to 75% TD&SS in a recovery boiler. The evaporators are used in the first stage of the feed concentration process. The system uses a heat pump principle: steam produced during the boiling of the falling liquid film is mechanically compressed and condensed on the outer surface of a vertical tube evaporator. Most of the condensation and compression heat is recovered. Reducing the rate of scale deposition and increasing the interval between two successive cleaning operations of vertical evaporators used in the MVR scheme was identified as an essential component of operation costs and given special attention. To assist the mill in assessing practical methods for achieving this goal an experimental pilot evaporator and a numerical model were developed and used first at the Alberta Research Council in Edmonton, Canada, and then at the mill location. The mill uses a different model for control and supervision of system parameters. The magnitude of the (critical) temperature difference (CTD) across the laminar sub-layer of boiling liquid film is calculated and is recommended in this paper to be used to quantify the fouling tendency. Further to recommendations resulting from previous experimental investigations [1,2] as well as in this study, the mill introduced additional process control parameters to reduce and maintain the temperature drop across the effluent boiling film to a maximum range of 2–4°C. In addition to CTD, the wall (top-bottom) axial temperature difference (ATD) has been identified as another criteria for assessing potential scale deposition during evaporation-concentration. Calculations and experimental measurements performed with the pilot evaporator [3] suggest that increasing the circulation rate of effluent pumped from the sump to feed the liquid film at the top of evaporator tubes has a positive effect on reducing the CTD and the ATD. During four months of laboratory investigations with a pilot evaporator, non-uniform liquid distribution among vertical evaporator tubes of the evaporator was observed and is discussed separately. This paper will present the model and mill observations and summarize the main results and suggested practical strategies for reducing the rate of scale deposition and improving the system economics.
Rapports d'organisations sur le sujet "Thermo-wood"
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Gurtowski, Luke, Joshua LeMonte, Jay Bennett, Brandon Lafferty et Matthew Middleton. Qualification of Hanna Instruments HI9829 for the Environmental Toolkit for Expeditionary Operations. Engineer Research and Development Center (U.S.), septembre 2022. http://dx.doi.org/10.21079/11681/45520.
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A new, commercially available, field-portable water sensor was evaluated for efficacy during operation and compatibility with current Environmental Toolkit for Expeditionary Operations (ETEO) software. The ETEO provides sensors to Soldiers to rapidly identify and quantify environmental contamination in soil, air, and water at potential new base sites during initial reconnaissance to ensure safety and minimize unnecessary remediation efforts by the Army. In addition to streamlined environmental baseline survey (EBS) reporting, the ETEO can provide rapid analysis of potential environmental contamination to support various Military applications. The Hanna Instruments HI9829 multiparameter water meter was selected following a survey of commercial off-the-shelf (COTS) technologies and analyzed by researchers from the US Army Engineer Research and Development Center (ERDC) for inclusion in the ETEO design since it can rapidly and accurately measure 14 different properties. Usability tests were conducted with researchers unfamiliar with the technology, and a set of standard operating procedures (SOPs) were developed to operate the device. The software for the tool was successfully integrated into the ETEO system for rapid data analysis. The HI9829 has been demonstrated in various scenarios at ERDC and other locations; including Ft. Leonard Wood, MO, at which several visitors reviewed the operation of the equipment and other ETEO technologies. The Thermo Scientific Gemini, another sensor, which can detect organic constituents in various matrices via Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy was also investigated but eliminated from the ETEO design as it could not adequately detect a Military-relevant compound in an environmental matrix. Regardless, the addition of the HI9829 provides water quality monitoring to the ETEO design and greatly improves its capability to address various applications.