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591 Uppsatser om Wood fuels - Sida 4 av 40

Epixylic lichens and bryophytes in young managed forests : substrate preferences and amounts of dead wood

Dead wood is important for many species. The amount of coarse dead wood (diameter >10 cm) is much lower in managed forest than in unmanaged forests. Stumps constitute the largest proportion of the volume of coarse dead wood in managed forests. Since stump harvest for biofuel may increase, the amount of dead wood will decrease even more, which may threaten biodiversity. The first aim of this study was to compare the amounts of fine woody debris (FWD, .

Vad tycker skogsägare om virkesinköpare och inköpsorganisationer? : utveckling av ett skogsbolags tjänster och köpverksamhet till privata skogsägare

The private forest owners play a key role in the supply of round wood to the Swedish forest industry. Today it is a keen competition between forest companies about the wood from private forest owners. In order to get access to the wood from the private forestry you need to be an attractive collaboration partner, who can offer long-term collaboration, service at top-level, and acting for good prices to the forest owners. This work aims at analysing the situation on the market today. It gives Sveaskog purchase department a good view of the forest owners? opinion in general about the existing purchase activities. Forestry service level and timber prices are determining factors for a successful relationship between forest company and forest owner.

Inverkan av olika joner och jonconcentrationer på porstorleksfördelningen i trämassa-fibrer

The basic ingredient of paper is the individual wood fibers. The property of the fibers depends on a variety of factors e.g., method of pulp production and processing. The final sheet quality depends in part on how the fibers interface between each other and therefore factors that affect the fiber size are of interest.The flexibility of the fibers depends in part on the pore water i.e., the fiber swelling. The sheet becomes less flexible at low water content which gives a loss in strength. Thus it becomes desirable to increase the water uptake.The experimental investigation described in this report consists of exposing the wood fibers to different ions and ionic strength and then measure the pore size by thermoporosimetry where a DSC (Differential Scanning Calorimeter) is used.

Hur såg Birkas hamn ut och vilka transporter behövdes?

What is located on the bottom in the water outside of Birka? Remains of a water palisade or jetties and other constructions.Birka a Viking Age town that existed between AD 750 and 975 was located on the northwestern part of the small island of Björkö, in the Mälar archipelago of the Baltic Sea in Sweden. The Town was protected onshore by a hill fort and a town rampart. It is a widely spread assumption that Birka had a water palisade as a part of its defense. There are logs and other remnants on the bottom of the lake dating back to the Viking age.

Competition for forest fuels in Sweden : exploring the possibilities of modeling forest fuel markets in a regional partial equilibrium framework

This thesis project focuses on the need for better tools for analyzing competition for forest fuels in Sweden, in particular how policy measures may influence the market and involved actors in different regions of Sweden. Raw materials from the forest have for long constituted important inputs in the Swedish forest industry. Today some of these raw materials are increasingly used as inputs also in bioenergy production, largely driven by bioenergy promoting policies, and there are signs of increased competition for forest fuels which may have various and uncertain effects on the industries in question. The thesis project explores the possibilities to adapt previously used forest sector equilibrium models into a new model suitable for analysis of Swedish forest fuel markets, called the Swedish Forest Sector Trade Model (SFSTM). The approach takes into account regional differences in supply and demand for 23 types of products produced and/or used by eight types of producers, plus consumers, in five different regions (four Swedish and one international).

Liquid diesel biofuel production in Sweden : a study of producers using forestry- or agricultural sector feedstock

The transportation sector is the only sector of the Swedish society that is still increasing the emissions of carbon dioxide and other green house gases. Diesel fuel represents one of the fuels that contributes to these emissions and the use of diesel fuels is increasing every year. The main purpose of this study was to make an estimation of the current business situation for producers of liquid diesel biofuels in Sweden such as biodiesel, synthetic diesel and crude tall diesel and examine the forces of competition of the industry today and its future prospects. The study revealed that the rivalry among the existing firms was low mainly due to the geographical spread of the companies. Moreover the success of the biodiesel industry was influenced by a long-term guarantee of the tax exempt for biofuels and by the price level of petroleum diesel.

Följdeffekter av olika användningssätt för vedråvara : en ekonomisk studie

Since the turn of the millennium a sharp increase in the interest for bio energy has been observed. Important reasons for this growing interest can be due to the fact that fossil fuels are a finite resource. A net discharge of greenhouse gases occur when fossil fuels are burned. The discharge of greenhouse gases are considered to be the main reason to the greenhouse effect. Means of control to increase the use of bio energy has been introduced and, as intended, the use of bio energy has increased. As a result of the legal provisions the ability to pay for bio energy has increased, which the forest industry view as a problem.

Clear-cut and substrate characteristics important for the occurrence of the beetle Upis ceramboides

Disturbances, such as fire and wind, are important for saproxylic beetles (= beetles depending on decaying wood) to gain substrate in boreal forests. Clear-cutting is an example of a man-made disturbance. Measures such as prescribed burning have been made to resemble natural disturbances. The aim of this study was to see which clear-cut characteristics are important for the occurrence of the saproxylic beetle Upis ceramboides. This is a species favored by open habitats and is said to respond positively to forest fires. The distribution area in Sweden for this species has decreased during the last two centuries and I wanted to see if there were differences between clear-cuts in Hälsingland, where it is very rare and decreasing, and Norrbotten where this study was conducted.

Skogsbristen i Smålands bruksskogar : en studie av träkolsförbrukning vid Storebro Bruk 1793-1850

The forest in the county of Småland has been utilised for a long time. One of the most important forms of utilisation of wood has been charcoaling for the benefit of the iron industry. Shortage of forest in relation to the iron industry, was discussed already in the 17th century in Sweden. The aim of this study was to analyse the purchase and consumption of charcoal at Storebro Bruk, an ironwork in Småland, during the period 1793-1850, as well as analyse the shortage of forest at the time. To determine the utilisation of the forest in the area, I have used historical sources from Storebro Bruksarkiv.

Tidsåtgång för rundvirkesmottagning på Södra Cell Mörrum

This study was made for the round wood transport company MT Transport AB. Time studies were made in order to analyze time consumption on the mill site for timber trucks delivering round wood at the Södra Cell Mörrum mill. The most interesting was to see how much of the time spent at the factory that was waiting time. In three weeks the study was going on and the drivers were clocking it themselves..

Upptryck : En jämförelse mellan RIDAS och internationella riktlinjer

Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).

Fuktomlagringar i välisolerade ytterväggar : En undersökning för att fastställa en rimlig inbyggnadsfuktkvoti träreglar med fuktsimuleringsprogrammet Wufi 2D

To save energy it?s popular to build houses with low energy loss. In these houses the walls are keeping a lower temperature in the external side which leads to a higher relative humidity. In addition more material, such as wood studs, are used which means that there is more moisture to dry. More moisture in combination with higher relative humidity may pose a higher risk of microbial growth.

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).

Rökgaskondensering och skrubber till vedeldade villapannor :

This paper deals with the opportunities for the technique of condensation, for wood fired household heaters, on the Swedish market. In this project the condenser is preceded by a scrubber and both energy exchange and separation of unburnt particles have been studied. The facility studied is connected to a wood stove at 30 kW. The tests would show that the effect from the stove never reached above 16 kW. This might be a result of the low temperature of the water going into the stove, from the condenser. In addition to this the wood was not of highest quality and the stove could have needed some maintenance before the tests.

Hästars aktivitet och liggtid på madrasserade gummimattor i box

Sleep is essential for all mammals and they all have different sleep patterns. Wild horses normally spend 2-8.5% of a 24-hour period in recumbent position while stabled horses lie down 11-20%. To fulfil the need of rapid eye movement (REM) sleep the horse must lie down with support against the ground for the head. The lying behavior can be affected by external stimuli such as age, food intake, bedding materials and if the horses feel safe or not. This study investigates the lying behavior of horses on different bedding materials; wood shavings and filled rubber mats (HIT SoftBed®).

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