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91 Uppsatser om Bark - Sida 1 av 7

Teknisk och ekonomisk analys av en bränslekonvertering vid SIA TallOils pelletsfabrik :

At SIA TallOil's pellets factory in Latvia wood shavings and saw dust are dried with flue gases from a gas burner. TallOil wants to replace the gas with a biofuel that is available at the pellet plant. The reason for this is the unstable gas market in Europe in combination with the fact that TallOil wants to improve its profile as supplier of renewable bio fuels. In this project the technical and economical possibilities for a fuel conversion to ether Bark powder, wood shavings or wood powder have been investigated. These fuels should be burned in one of the following applications: TPS BioSwirl, VTS Multifuel burner or Saxlunds bio fuel combustion plant Due to the fact that the fuel alternatives available are relatively common except for Bark powder, the work has mainly been focused on Bark powder.

Factors affecting bark-stripping by red deer (Cervus elaphus) : the importance of landscape structure and forage availability

Bark-stripping by red deer (Cervus elaphus) cause extensive damage to economically valuable spruce trees (Picea abies) in Swedish forests. The underlying causes for Bark-stripping are not fully understood, and the frequency and severity of damage unpredictably differ between regions. In this study, I investigated if landscape structure (e.g. agricultural dominated landscape opposed to forest dominated landscape), forage availability, population density and disturbance (e.g. roads and settlements) affect Bark-stripping frequency.

Utvärdering av produktionsrapporterad volym för contorta

The background to this study is that the forest company, Holmen, has found large discrepancies between harvested volume and the measured volume at the industry. Factors like Bark features, breakage, double tops, bends and stem damages was noted, and all stems were measured manually. Hypothesis testing with the method "random in pairs" were used to examine whether the harvester measured values significantly differed from the manually measured. The result of a properly calibrated harvester shows in average underestimation of the volume with Skogforsk Pine as a Bark function. This means that the harvester isn´t the reason why the volume measured in the industry is lower, the fault is elsewhere. The study also indicates a need for a unique Bark function for logepole pine..

Ett gammalt kulturlandskap i Vindelfjällen : skogshistoria och markutnyttjande i Vuornavagge under 300 år

Humans have inhabited mountainous areas in northern Sweden since the end of the last glacial period, ca 8000 B.P., and their presence has marked the landscape in various ways. Older traces include the remains of hearths and dwelling sites, but there are also remains, such as culturally modified trees (CMT's), resulting from more recent activities in forested areas. This study aimed to document how people, both indigenous Sami's and Swedish settlers, have used an area northwest of Ammarnäs in Västerbotten, during the last 300 years, and what traces their activities have left in the area. I used historical records as well as an inventory of CMT's in the area to address this aim. Historical records of Sami activity are meagre, but it is clear that the people of the Ran and Gran Sami villages utilized the area long before 1500 A.D.

Subjektiv och objektiv bedömning av underlag på svenska hopptävlingar på elit- och nationell nivå

Bark-stripping by red deer (Cervus elaphus) cause extensive damage to economically valuable spruce trees (Picea abies) in Swedish forests. The underlying causes for Bark-stripping are not fully understood, and the frequency and severity of damage unpredictably differ between regions. In this study, I investigated if landscape structure (e.g. agricultural dominated landscape opposed to forest dominated landscape), forage availability, population density and disturbance (e.g. roads and settlements) affect Bark-stripping frequency.

Lakningsförsök med furubarksflis : en utredning om utsläpp av fenolföreningar samt metallsorption

The filters used today to purify water are often expensive and the need to find new filter materials is substantial. Studies of pine Bark have shown that this is a material that may be used as an alternative to conventional filter materials, such as activated carbon. However, the study of pine Bark has shown that a leakage of phenolic compounds may occur when using the material for water purification. Therefore, the purpose of this report is to investigate the release of phenols from pine Bark, in order to evaluate the use of pine Bark as a filter material. Another assignment is to investigate the amount of metals adsorbed by the filter material.

Effekterna av urbanisering, barksprickedjup och solexponering på lavfloran i sydöstra Sverige

Studies have shown that air pollution, as well as Bark fissure depth and sun exposure of a tree can have an effect on lichen growth as well as abundance of lichen species. The aim of this study was to find out the relative importance of these factors. 211 oaks in south eastern Sweden were surveyed for presence of 17 lichen species, as well as the total number of lichen species. Half of the trees were situated in urban areas and half in the countryside. For each tree the Bark fissure depth was measured and the sun exposure of the trunk was estimated.

Möjligheter att öka effektiviteten och det ekonomiska utfallet av barkhanteringen vid Seskarö sågverk :

The sludgeBark and to a certain extent the Bark were until a decade ago waste products without any economic value that were thrown away. A number of environmental laws and increcing energy prices have improved the prerequisites for increasing the use of these materials. At Seskarö sawmill they burn the sludgeBark and a great deal of the Bark in the sawmill furnace. The sludgeBark has a number of disadvantages compared to Bark during burning. The sludgeBark is often wet which means the energy net from burning often gets low.

Habitat preferences and reproductive success forthe threatened longhorn beetle Plagionotusdetritus

Plagionotus detritus is a threatend longhorn beetle that only exists at one site in Sweden. It is saproxylic and depending on recently dead coarse oak wood for its larval development. Trees at Djurgården, Stockholm that have been colonized by Plagionotus detritus has been studied to find out the habitat preferences of the species and to see what affects the density of beetles in a tree. The Bark of some trees and wood from the breeding project at Nordens Ark has also been studied to find out what affects the species reproductive success. The reproductive success was measured in two ways, the larval mortality and the size of the hatching holes.

Klimatfaktorers inverkan på granbarkborrens svärmningsintensitet i Medelpad

The spruce Bark beetle (Ips typographhus) is one of the 25 000 species of insects in Sweden, an insect of great economic importance because it can alone terminate forest of high value. During the past decade, insights of climate change received with increasing attention. If the future brings a milder climate in the north and therefore a longer growing season, one would think that it would only affect the forestry to the better? Yet in recent time, outbreaks after storm felling seems to occur more frequently. The Spruce Bark beetle ruins millions of cubic meter of Norway spruce (Picea abies) in Sweden alone, with more frequent storm felling and a larger amount of wind thrown threes in the forests there will also be room for an advancing reproduction.

Skogens Eko

Naturen inspirerar mig, i detta projekt jobbar jag med strukturen hos trädstammar och Bark, och översätter det jag ser till vävda textiler. När jag befinner mig i naturen känner jag mig ofta lugn och kan koppla bort allt annat i min omgivning. Det lugnet vill jag återskapa och föra in i en rumslighet. I Barkens olika strukturer såg jag intressanta varierande ytor som jag ville jobba med i textil. I mitt examensarbete har jag designat textilier med uppmätt akustiska egenskaper för offentlig miljö.

Njurvolym samt relation mellan bark och märg mätt med ultraljud hos katt

Scandinavian Ragdoll Club rekommenderar screening av njurarna med ultraljud hos ragdollkatter inför avel, detta för att leta tecken efter kronisk interstitiell nefrit (CIN) som misstänks drabba dessa katter i högre utsträckning än andra raser. Den undersökande veterinären ska bland annat göra en subjektiv bedömning av förhållandet mellan Bark och märg. Syftet med denna studie var att upprätta normal- och referensvärden för volymmässigt förhållande mellan Bark och märg hos friska katter då detta saknas. Tre snitt (sagittal-, dorsal- och transversalsnitt) av vardera njuren sparades och mätningar för längd, höjd och bredd för både total njurstorlek samt märgstorlek utfördes. Volymen för hela njuren, märgen samt Barken beräknades genom att likna njuren vid en ellipsoid och normalvärden för förhållanden mellan Bark och märg räknades ut.

Produktionsskillnader och virkesskador med olika typer av matarvalsar :

Earlier investigations showed that damages on timber from feeding rolls could be within the lower classes of damage according to VMRs classes. Knowledge about differences in productivity between kind types and aggressive types of feeding rolls is necessary because it should influence the question about damages on timber caused by different feeding rolls. In this study the production and timber damage in a harvesting head were evaluated at three levels of pressure (8, 10 and 14 MPa) on the feeding rolls, and with three different types of rolls. One type, the rubber cushioned steel plate roller had 10 mm studs and rubber damping, one ?middle? type made of solid steel with 14 mm studs, and one aggressive type, also made of solid steel with 18 mm studs.

Biomass losses during short-term storage of bark and recovered wood

Storage of biomass is associated with problems like heat development, biomasslosses, and reduction of the fuel quality. Certain processes such as biological- andchemical degradation are responsible for these storage problems. This master?sthesis was carried out at Vattenfall Research and Development AB and is alignedtowards quantifying the biomass losses from short-term storage (1-2 months) ofBark and recovered wood. The biomass was stored in outdoor piles during differentseasons, campaign 1 (summer) and campaign 2 (autumn).

Vilken är den teoretiskt optimala toppdiametern på bokmassaved vid motormanuell avverkning?

The bioenergy market has been introduced relatively late in a perspective of the Swedish forestry. Nowadays branches and tops are used more frequently as bioenergy after harvesting. Therefore, it has developed a competitive situation between pulpwood and bioenergy. This situation has even established some questions. Two examples of these are: ? At what top diameter should the final piece of pulpwood be crosscut to get the best economically result? ? Should the top diameter, at the final piece of pulpwood, be crosscut at a thicker or smaller diameter than what is done today? The purpose of this report is to answer these two questions when the harvesting is made motor manually in beech stands.

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