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3656 Uppsatser om Wood quality - Sida 1 av 244

Stubbtransporter och bränslekvalitet hos stubbved :

Stump wood is a hot alternative when the heating plants demands more and more forest fuel. The aim with the study has bean to calculate the costs in four different systems for transportations of stump wood, examine if there are any differences in fuel quality for the stump wood in the different systems, analyse if the fuel quality in stump wood is affected with the time it lays by the road side and how much space the stump wood demands on the road side. To calculate the costs for the different systems a system analysis was carried out, where some of the costs were collected through field studies on Holmen Skog stump experiment and other costs were collected from literature and contacts. Data for the fuel quality study was collected from Eons heat plant in Norrköping. Data for the study of how much space stump wood takes along a roadside was collected from field studies.

Förbättrat råvaruutnyttjande vid kvalitets-sortering av timmer : utvärdering av analysprogrammet Stockholmen för automatiserad timmersortering i dimensions- och kvalitetsklasser hos BARO WOOD AB

The aim of this thesis was to analyse BARO WOOD AB:s timber measuring and quality sorting and to evaluate the analyse program Stockholmen. The purpose was to get a better understanding for the quality sorting made at BARO WOOD AB today, analyse differences in center board quality from logs with a good quality and logs with a bad quality, suggest new sorting criterias developed from analyses made with Stockholmen and to evaluate the program Stockholmen. All analyses are based on data gathered in a test sawing made at BARO WOOD AB in June and July 2002. The test sawing was made on four different diameter classes and every diameter class consisted out of A or M-grade logs, with a better quality, and B-grade logs with a lesser quality. The logs where sorted out with BARO WOOD AB:s existing quality criterias.

Pelletskvalitet : Test av olika råvarumixer i pelletstillverkningen vid Rindi Västerdala AB:s bioenergikombinat i Vansbro

Fuel pellets are a refined bio fuel mostly consisting of residues from sawmills and wood industry. At Rindi Västerdala AB's combined bio energy plant in Vansbro fuel pellets are produced, while the waste heat from the process is used for district heating. The pellets are produced from sawdust, wood shavings and dry wood chips that is dried, milled and pressed into small cylindrical rods. The advantage of refining the wood material in this manner is that the energy value is greater per unit volume and unit weight, thereby the cost of transportation per energy unit is reduced. Also, less storage space is needed.Pellet manufacturing is a complex process since many parameters affects the final results.

Energy efficient storage of biomass at Vattenfall heat and power plants

Storage of biomass is often associated with problems such as heat development, dry matter losses and reduction of fuel quality. The rise in temperature can potentially cause a risk of self-ignition in the fuel storage. Moreover, emissions from storage piles can cause health problems in the surrounding. The dry matter losses and reduction of fuel quality can have economical effects. The aim of this thesis project is to develop guidelines on how to store large amount of biomass at Vattenfalls heat and power plants in an optimal way.

Bevattning av lagrat virke vid svensk skogsindustri : omfattning och miljökonsekvenser

Most of the saw and pulp industries have stored wood nearby their production, the main reason is to have a continuous wood flow to the production. Wet storage of wood is of great importance to keep the Wood quality. Without water sprinkling the risk of drying outand decomposition through biological activity increases significantly and will result in a negative effect on future production and quality. One drawback of wet storage of wood is the leaching of chemical substances into the surrounding recipient. The log yard run-off contains phosphorus, nitrogen, phenols and organic substances. These substances can cause problems for the surrounding environment. The main objective of this project is to gain an understanding of the wet storage used by the Swedish wood industry and estimate the environmental consequences that run-off water will have on the recipient.

The French market and customers? perceptions of Nordic softwood offerings

The study of the French market for softwood has been done in collaboration with VIDA AB. The aim of the study was to investigate important product quality and service quality dimensions, the customers? perception of the offering and generally describe the French market and present actors. The market for softwood around the world changes over time and new markets can mean opportunities for the sawmilling industry. The French market is the second biggest European market for softwood, has had presence of actors with sourcing of raw material from the Nordic countries for decades and there is a growing interest for building with wood. Theory being used is about the different dimensions that make up the total quality of softwood, together with intangible dimensions making up the total offering that helps the sawmilling industry to create positive perceived value for the customers. Methodological approach in the study was a case study research design, aimed at providing knowledge about one specific subject in one context. The general description was mostly carried out by literature studies and data from various statistics sources.

Uppfattningar om tryckved bland träbearbetande företag i Sverige :

The primary purpose of this study has been to investigate the Swedish timber industry?s perception of compression wood. A secondary aim has been to describe particular areas within the production process where compression wood is likely to cause problems. This study has mainly been carried out as a questionnaire. In order to connect the findings to current research, additional information has also been collected by means of a literature review. The questionnaire has been intended for sawmills and wood-manufacturing companies from various production classes and owner categories, as well as from different parts of the country.

Effekt på värdeutfallet av sågad vara vid övergång från 30 till 60 cm moduler : - en fallstudie av Moelven

The purpose of this study is to explain how the value of sawn wood changes when sawn wood are cut in 30 respective 60 cm lengths. The raw material into the saw mill will mainly be bucked in 30cm and 60 cm modules. There will also be two alternatives where the timber will be bucked special lengths, 370, 490 and 550 cm but also in 490 and 550 cm.The method used for the study is to simulate both cutting and sawing the woods. For cutting the simulator Timan is used and for sawing the simulator Timberopt is used. When data is generatedfrom the simulators, calculations of some key figures is done and also how much the revenue need to be increased for the sawn wood in order to cover for the increased costs of changing sawn woodfrom 30 cm to 60 cm modulesThe conclusion is that the single biggest reason, impacting the value of the sawn wood is the cutting at the saw mill.When going from 30 to 60 cm modules, the impact will be that the customers to the saw mill must pay more to increase the revenue by at least 10% for the sawn wood in order to justifice the changein production.It is also possible to increase the value of the products further by bucking the timber in three lengths, 370, 490 and 550 cm, in order to get 12 % increase of the share of longer sawn wood (>= 480 cm)..

Skogsbrandens påverkan på död ved :

Fire is an important ecological factor, but its consumption of coarse woody debris, CWD, has hardly received any attention. In this study, I investigate the consumption in relation to the time of initial flame exposure and propensity for continued combustion of standing CWD of pine (Pinus sylvestris). Two types of CWD were studied. Firstly, wood that had been dead for one to ten years. Secondly, wood that had been dead for several decades. In the burning experiments, logs of approx.

Trä som fasadmaterial ? behandling och beständighet

Since prehistoric time man has used wood to build their environment. The material?s availabilitycombined with its good mechanical properties has often made it the material of choice. Like allmaterials exposed to natures degradative processes the properties of wood decreases over time.Rot, UV radiation and attacks by insects and pests damage wood if not protected. Since we wantwhat we build to consist, optimizing our building materials durability is of great interest.Techniques and methods for increasing the endurance of wood have been developed in severaldifferent places and for a long time.

Buddhismens krigare : Om buddhism, politik och våld

This graduation paper is based on my interest for wood and its different tonal quality?s.After some time of thinking I decided to write my paper on the tonal difference between two of the most common woods in guitars, East Indian Rosewood and European Maple. I had built two identical guitars before my graduation paper in which the difference was the wood the back and sides were made of. One was being made of East Indian Rosewood and the other being made of European Maple.I chose to speak with a number of people with different angle of approach to the two kinds of wood and its tonal difference and quality?s.

Epoxidised linseed oil as hydrophobic substance for wood protection : technology of treatment and properties of modified wood

Public concern about the release of toxic compounds from wood-based products drives legislation towards enforcing industries to find and use more sustainable solutions for wood treatment. Plant oils are good alternatives to treat wood, minimizing or even neutralizing the impact on the environment. Wood modification with epoxidised linseed oil (ELO) and acetic acid as catalyst has proven a suitable method to impregnate and protect wood. However, the mixture presents a serious inconvenience because of the quick polymerization of the ingredients that limits its practical application. Therefore, this study was designed to evaluate an alternative method using a two-step process which bypassed the problem above.

Visuell handelsortering av furu och gran

This essay concerns the visual trade grading of pine and spruce.In the 1800s developed rules for sorting of wood. The rules used to facilitate the export trade.The terms of the regulatory sorting systems developed in the 1900s. While it still used some of the older terms.The essay deals with how the grading rules affect the use of wood and how the rule work and how the terminology works.Some of the terms used for sorting are O/S, Kvinta, Utskott and A,B,C,D.You sorting by counting the numbers of knots, cracks and other characteristics of each piece of wood.The sawmills have much influence in how the rules developed.Today it is often already determined in the sawmills which uses each piece of wood most have..

Planteringsförbandets inverkan på bestånd av contortatall (Pinus contorta var. latifolia) med avseende på volymtillväxt och virkesegenskaper

At the beginning of the 1970´s forestry feared an imbalance in the future wood supply. Because of this anticipated "timber slump" forest companies undertook a variety of measures to counter this. One of these measures was the introduction of exotic tree species. The choice finally ended up with lodgepole pines which were considered a fast growing tree species compared to our native tree species. Theambition for the new lodgepole pine stands were to run these with rotation periods of between 40-60 years, thus smoothing out the ?timber slump? that was anticipated.

Betydelsen av skogsbruksplaner som verktyg vid anskaffning av virke

Forest management plans have been sold to private forest owners by wood supplying companies for a long time. These plans are considered to be effi-cient tools to identify measures and wood volumes, and are simply a starting point for discussions between private forest owners and round wood pur-chasers. However, large variations are observed between different purchas-ers, in their usage of the plans. The purpose of this report is to identify to what extent a forest management plan can promote an increase in the amount of wood which a round wood purchaser can obtain and to find differences in the way of using the plans between different wood purchasers. Furthermore, the purpose is also to ana-lyse if varying owner structures can be underlie variations in the selling of forest management plans. Qualitative interviews with nine of Stora Enso?s round wood purchasers were performed.

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