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2171 Uppsatser om Springback and density of the compressed wood. In addition - Sida 3 av 145
Traditionella och samtida bottenbj?lklag: med fokus p? isoleringsmaterialen
The survey aims to shed light on traditional and contemporary bottom floor frames, their construction
and different insulating materials; mineral wool, wood shavings and charcoal. The purpose is to
analyze and discuss the similarities and differences as well as the pros and cons with a focus on the
construction and the different insulating materials.
The work has been limited to comparing two different wooden floor frames. The first one is based on
a real floor frame from an older building, this example is presented as the traditional floor frame in
this study and are from around 1940. The other floor frame is presented as a contemporary floor frame
and is based on wood building type descriptions and literature.
Qualities and supply of suitable dead wood for Ceruchus chrysomelinus and its dispersal pattern in a translocated population
The wood-living beetle Ceruchus chrysomelinus is a rare species connected to natural
forests. In Sweden, it is red-listed as endangered (EN) and an action plan for its preservation
has been done by the Swedish Environmental Protection Agency. In this work I have
therefore investigated how a translocation of the species succeeded after 17 years. I aimed
to study the species dispersal biology, its substrate preferences and the supply of suitable
wood on this site. The study was performed during 2012 in Pansaruddens nature reserve
close to Uppsala in Sweden, which is a spruce dominated forest.
Hör träbränslena hemma i växthusen? :
With the elevated oil prices of today it is necessary to look for other heating alternatives. If the oil price continues to develop in the same way it has done the last years it will soon be impossible for many producing garden companies to survive.
The purpose of this diploma work is to compare three different fuel options in order to find the most economic one considering the conditions of Katrinebergs Handelsträdgård AB.
In relation to oil it is profitable to change to any of the three alternatives: wood chips, wood pellets and grain. The most profitable option is to change to wood chips. This alternative has a payoff time less than three years and after that the annual saving compared to the oil is relatively high. The annual cost is 65 % of the cost of the oil alternative.
Framtidens energilagring : en studie av befintliga samt potentiella metoder fo?r lagring av fo?rnybar el pa? ett ha?llbart sa?tt
In today?s society there is an increasing demand for renewable energy sources such as sun and wind power. These sources are intermittent, and energy storage is therefore needed to ensure a constant power supply. This report compares pumped hydro energy storage (PHES), compressed air energy storage (CAES), flywheels, batteries, super magnetic energy storage (SMES) and hydrogen energy storage.The opportunities for further development are limited for PHES and CAES in comparison with the other technologies. Lithium-ion batteries and hydrogen energy storage are considered to have the most potential in the future.
Död ved i vatten - funktionella strukturer och dess påverkan på öring (Salmo trutta, L.)
The background to this work was to see if there was a connection between large woody debris (LWD) and the presence of brown trout in our Swedish forest streams. Previous researches by Degerman et al. (2004) have shown that there is a strong correlation between the amount of dead wood and the presence of brown trout. The goal was then to find a way to restore, maintain and increase the trout habitats by constructing and adding manmade wooden structures that would mimic natural deadwood and its features in flowing water. The inspiration was partially taken from a water restoration program in the Klamath River of northern California, USA.
Produktivitet och lönsamhet vid skörd av skogsbränsle i klen björkgallring :
The aim of the study was to compare productivity in first thinning of birch stands, when either energy- or pulpwood was harvested. The systems total profitability was also compared by including forwarding and chipping costs. A Gremo 950 HPVR harvester was used and the same driver was used under the entire study. During the pulpwood harvest a Logmax 4000b harvester head was used and a feller buncher head made by Silvatec was used during the energy wood harvest. Six study unit pairs were located in a birch dominated stand outside Ängelholm in Skåne.
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.
Export of wood pellets from British Columbia : a study about the production environment and international competitiveness of wood pellets from British Columbia
The global wood pellet market has seen a rapid growth after the adoption of the Kyoto protocol and the renewable energy incentives created within the European Union. The global consumption of wood pellets reached 13,5 million tonnes in 2010 and several experts estimate the consumption to be between 35-50 million tonnes by 2020. These forescasts raise the questions which regions that can supply this vast amount of wood pellets and what the conditions are for producing it.
This study evaluates the conditions for wood pellet production and export from British Columbia, on Canada?s west coast, focusing on existing industry structure, raw material supply and the distribution chain.
Provmetod för olje- och partikelöverdrag från kompressor till tryckluftssystem
Compressed air is an energy source that is widely used in today's trucks and buses.Compressor located next to the engine supplies the pneumatic system with the compressed air and is lubricated with the engine oil. Some of the oil follows the air flow in both liquid and solid phase. The solid phase, namely the carbon particles are created due to the high temperature in the compression chamber.Oil- and particles carryover softens and destroys the rubber material in the air valves and disturbs the mechanical function of various components in the pneumatic system. In order to reduce oil- and particles carryover is an Air Processing System (APS) set downstream the compressor.No method for establishment of oil- and particles carryover from the compressor exists at the moment. Therefore the filtration efficiency of APS is currently unknown.
Röjningsförbandets betydelse för avverkningsekonomin i södra Sverige :
The aim of this work is to demonstrate how the net present value (NPV) at the time of the first thinning depends on the spacing after pre-commercial thinning, and show how net value from first thinning in same stand is influenced.
This study is performed with models based on non-distant dependent growth models for single trees. Two different growth models have been used, one for cleaning (pre-commercial thinning) and one for thinning. The first one yields stem density distributed over diameter classes. In the second one, (the thinning model), it is possible to choose when thinning should be done, the thinning method, thinning grade and numbers of thinning.
Död ved i gallrad skog och nyckelbiotoper : en jämförelse av habitatkvaliteter för vedlevande lavar och mossor
A high amount of dead wood is one of the most important prerequisites for high biodiversity on forest land in Sweden. Dead wood is most abundant in young forests, thinned forests, woodland key habitats and protected forest land. In old-growth forests most of the dead wood consists of logs and snags, whilst in managed forests a huge proportion of dead wood is made up of logging residues like stumps and FWD, fine woody debris (< 10 cm diameter). All these different types of dead wood may serve as substrates for epixylic bryophytes and lichens. However, few studies have been conducted on the relative importance of these different fractions of dead wood for the occurrence of bryophytes and lichens, especially when considering dead wood on thinned forest land.
Automatisk tändning till modern vedpanna
If you have access to wood, a wood burning boiler is a cheap way to heat your home, but it is certainly not the most convenient option. Wood requires many operations and management, which takes time. One way to reduce this workload is to have a modern boiler with automatic ignition. Enertech/CTC has a desire to create an accessory with automatic ignition to a modern wood burning boiler. Today there is no boiler on the market that can ignite firewood automatically without the introduction of paper and sticks.
Efterfrågan av grova sågade dimensioner och hyvlade produkter bland Wallnäs AB:s kunder : en marknadsundersökning
The purpose of this thesis is to study whether there is a demand for sawn wood products of large dimensions and planed goods among Wallnäs AB:s customers. The thesis consist of two main parts, one survey among Wallnäs present customers and another one which purpose is to increase Wallnäs customer base. Finally there is a chapter that describes what properties the raw material has to have in order to produce the demanded products.
The survey to the present customers was conducted through a questioner. A sample of those who stated an interest for either sawn wood products of large dimensions or planed goods, were later contacted for a telephone interview.
To reach out to new customers, relevant companies has been identified through the Swedish Trade Councils data base and through the member list of the Timber Trade Federation.
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.
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.