Le trieur Pulpwood Sorter de Simco/Ramic a fait l'objet d'essais dans le but de déterminer s'il était capable d'extraire des copeaux sans écorce destinés à la pâte, à partir de copeaux produits en forêt et contenant des quantités connues d'écorce et d'autres débris. Les essais portaient sur quatre types de copeaux: des copeaux de feuillus provenant d'arbres entiers, des copeaux de résineaux provenant de troncs entiers, des copeaux de résineux provenant d'arbres entiers et des copeaux de feuillus produits par une ébrancheuse-écorceuse-déchiqueteuse à fléaux. Les résultats des essais donnent les proportions de copeaux acceptés et de résidus combustibles en pourcentage de l'approvisionnement total à l'entrée, et le rapport estime également le coût de triage par tonne métrique verte.
The purpose of this study is to investigate and record the principal problems associated with chipped surface quality at canter lines and evaluate degrade and value losses due to these problems.
Mill measurements were conducted in five member sawmills in British Columbia to evaluate the value losses and lumber degrades due to chipped surface defects. The test lumber was sampled from the planing mills to identify the chipping losses and main problems. The five types of chipped surface defects influencing lumber grade are: knot tear-out; failure to remove chipped spline channel; torn grain without knots; scalloping; and chipped thin end.
Average value losses for all mills were $11.4/MBF and $12.6/MBF in freezing and non-freezing conditions respectively. Removing the non-freezing data from one mill changed this to $11.4/MBF and $9.0/MBF respectively. Knot tear out caused 60% of lumber to be degraded. On average, over 55% of knots had tear-out. 42.3% of trim length was caused by failure to remove chipped spline channel.
This report describes some of the background and results of work done to date on second-growth western hemlock basic wood properties at Forintek Canada Corp. The B.C. Ministry of Forests (BCMOF) Research Branch, UBC Forestry Faculty and PAPRICAN were the other cooperating agencies on this project and they investigated live crown/tree growth relationships, strength properties of small clears, and pulping properties, respectively. Properties that were assessed by Forintek, both within and between trees include: relative density of wood, shrinkage, moisture content and relative proportion of heartwood-sapwood, bark thickness, content and distribution of compression wood, incidence and degree of spiral grain, incidence and severity of brown stain, and strength properties of small cleear bending samples. Naturally grown 90-year-old western hemlock stands represent much of the emerging timber supply in the B.C. coastal forest region. Information characterizing the commercial quality of this resource is needed now to support processing and marketing decisions and for product promotion. In addition, the BCMOF and industry members are making stand management decisions today which will determine the future quality of western hemlock. We can reduce the risk of making wrong investment decisions by providing information on how different growing conditions (e.g., biogeoclimatic zone, site, stand density, thinning) affect second-growth wood quality.
The objective of this project was to quantify the lumber value recovery up-lift that is achievable by adding surface defect detection to board profile scanning in sawmill edger optimization. Optimized profile edging solutions of 194 spruce-pine-fir sample boards were compared to optimized edging solutions that took into account surface defects as well as the geometric shape of the board. The edger optimization improvement was found to be marginal. Data analysis showed a benefit of only $0.13 per m3 of processed logs, an equivalent of $237.11 per shift. The findings of this report are mill specific. The value recovery figures were collected in a mill with given log supply, machinery and market orientation. A more significant up-lift in value recovery would likely be obtained for higher valued products produced from larger logs typically processed in coastal sawmills.
This report describes an analytical framework developed to assess the relative advantages and disadvantages of different building materials from an environmental perspective. The ultimate objective is to develop and make available a systems model which will allow building designers to assess the environmental impacts of using different kinds of building materials in structural applications.
When completely operational the model will deal with critical impacts on the physical environment, measured in natural units (e.g. gigajoules of embodied energy or kilograms of atmospheric emissions) in a holistic, cradle-to-grave framework. The model will be applicable to light commercial/institutional structures as well as single family and low-rise residential construction.
The purpose here is to report on our work to date, with emphasis on the framework and its application, and to facilitate an exchange of information with others who are taking parallel courses and grappling with similar problems. The report also includes some interim results for wood and steel building materials which demonstrate how the model can be used.
We start with a discussion of the concept of sustainable development because that concept is central to our approach. Subsequent sections of this report then detail the analytical framework and provide examples of the results we're obtaining.
Les auteurs définissent la qualité du bois en fonction de ses emplois, puis décrivent l'anatomie et la croissance du bois en regard de ses caractéristiques microscopiques et macroscopiques telles qu'observées en coupe transversale. Les exigences liées aux emplois sont énoncées selon les différentes classes de bois. Diverses caractéristiques déterminant la qualité du bois sont présentées et leurs conséquences pratiques pour la transformation du bois et les produits sont expliquées. Ces caractéristiques sont: la densité du bois, les variations de la densité, la répartition des bois juvénile et adulte, la proportion de duramen et d'aubier, la longueur des fibres, l'orientation des microfibrilles, le bois de compression, les noeuds, le grain ou la texture, le fil et les substances extractibles. Enfin, les auteurs traitent de la possibilité de modifier les paramètres de croissance de l'arbre et la qualité du bois grâce à un contrôle de la densité du peuplement. Les forestiers sont invités à prendre en considération les répercussions des travaux sylvicoles propres à chaque station.
The Forest Engineering Research Institute of Canada (FERIC) evaluated wood chip recovery and productivity at Weyerhaeuser Company Limited's pulp mill in Prince Albert, Saskatchewan. Frozen and unfrozen hardwood and softwood logs were debarked and shipped over a range of butt diameters and lengths. This report summarizes the chip recovery, quality, and productivity, and provides recommendations on how the operation and chip recovery can be improved.
