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487 Uppsatser om Wood chips - Sida 4 av 33

Bränsleoptimering av befintliga brikettpannor

Intresset för biobränsleproducerad energi har ökat i takt med att kunderna blivit mer miljömedvetna. På grund av detta har efterfrågan på briketter ökat samtidigt som träindustrin har haft det svårt i en sviktande konjunktur. Därför har ett examensarbete utförts i samarbete med E.ON Värme Sverige AB där undersökningar på bränslebyte i pannor avsedda för torra bränslen till fuktigare, stamvedflis har utfört.För denna undersökning har begränsningar införts på övre och undre effekt i form av uppehållstid och slutförbränningstemperatur. Intervallen är enbart beräknade på stamvedflis med 30 och 40 % fukthalt.Undersökning visar att det går bra att elda stamvedsflis i briketteldade pannor utan att emissionerna ökar så pass mycket att villkoren för anläggningarna överskrids om lasten hålls inom vissa intervall. Det möjliga effektintervallet ökar med minskad fukthalt på bränslet.Undersökningen har visat att det är bränslets kvalitet som är den mest begränsande faktorn..

En jämförelse av skogsmarksprisets utveckling mellan Sverige, Danmark, Norge, Finland, Estland och Lettland

During the twenty-first century the price of forest land in Sweden has increased heavily. Buying forest land has become more common and the stakeholders have grown in number. The countries around Sweden have through the globalization become connected in the market of round wood and wood products. The price of forest land and round wood are also close connected. The goal with this report is to make a comparison of forest land prices between Sweden, Denmark, Norway, Finland, Estonia and Latvia and to see how the prices have developed in the period 2000-2011. The prime factor in the comparison, except the direct price difference between the countries, is the round wood prices. The round wood prices give information about the economic situation in the countries and play an important role in the return on the forest land. The prices of forest land shifts heavily between the countries.

Torkning av flis med restvärme : Metoder för att sänka återledningstemperaturen

The purpose of this study has been to evaluate whether a Low temperature bio-mass dryer could be integrated with the local district heating system in Malå. The aim is to increase the thermal efficiency of the cogeneration plant in Malå, by lowering the temperature of the cooling medium. Another benefit that comes from this is improved combustion efficiency at the power plant, since drying the fuel causes an Increase of the heating value.Simulations has been made in Excel, and with use of linear regression, to find out if it is profitable. Data for this purpose has been supplied by the power company Skellefteåkraft and furthermore SMHI.The result of the Calculations shows that a very efficient bio-mass dryer is needed, if yield of investments should be made possible. An Investment of 4,27 Mkr, in a dryer, could at a such criterium return 60000 kr/year, if the price of the biomass is 190kr/MWh.

Skillnader i mulmvolymer mellan fem trädslag i Östergötlands eklandskap

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).

Identifiering av lek- och övervintringsområden för lax (Salmo salar) och öring (Salmo trutta) i Klarälven

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).

Energiutredning på Chips AB, Åland

En energikartla?ggning har gjorts hos Chips AB fo?r att underso?ka hur energin fo?rdelas o?ver de olika produktionslinjerna. Energianva?ndningen fra?n processer som a?r gemensamma fo?r alla produktionslinjer har ocksa? underso?kts. Energianva?ndningen fo?r dessa har fo?rdelats o?ver pro- duktionslinjerna eftersom produkterna a?ven ska ba?ra upp dessa energikostnader.

Fuktkvotens inverkan på oljeupptag och pigmentinträngning i tall (Pinus sylvestris L.) och gran (Picea abies L. Karst) vid impregnering med Linotechmetoden :

Wood has always been an important material for people, and it is used for many applications. As for example, fuel for cooking and heating houses, construction materials and for constructing means of transport. Since wood also is a material that with time biologically degrades due to activity by micro organisms and wood fungi it is important to find ways to protect and further lengthen the life span of the material when in service. One method is to decrease the amount of water in the material by impregnation with an hydrophobic oil. The Linotech method which uses only pure linseed oil is one such possible method. The aim of this study was to investigate the possibility to at the same time impregnate and stain/colour wood samples of pine and spruce by using the Linotech method.

En studie av utvecklingen av drivningsnettot i skogsbruket :

This master thesis consists of an investigation of the profitability per hectare in privatly owned forest land. The investigation is based on data collected from Skogsstyrelesen, Riksskogstaxeringen and Skogsforsk. During the last twenty years the prices on pulp wood and saw log have substantial decreased, but during the same time the the volumes from final felling have increased and the cost for felling has decreased, this investigation shows how the netprofit per hectARE after final felling has changed between year 1980-2005 This investigation shows that that the netprofit has stayed on a stable level during the years 1985-2005 even though prices pulp wood and saw log decreased. Much indicates that the demand of swedish pulp wood and saw log will continue to be strong or even stronger wich will give increased prices and an higher netprofit after final felling in the future.

Pelletering av tallspån : grundläggande studier

Wood pellets are an upgraded product of residuals from several wood processing industries, for example saw mills and pulp industries. The pellets are produced by pressing the milled and dried sawdust to cylindrical units with a higher density than the initial raw material. Pellets have great benefits compared to the raw material: high energy per volume, good transport and storage properties and homogeneity. Several parameters collaborate in the whole process, which makes it complex. Wood is a heterogeneous material, chemically and structurally dependent on wood parts, habitat and storage procedures.

Stöldskydd

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.

Kappa Control with Online Analyzer Using Samples from the Digester's Mid-phase

In the pulp industry, digesters are used to disolve lignin in Wood chips. The concentration of lignin is measured and is called the Kappa number. In this thesis, the question of whether an online Kappa sensor, taking samples from the mid-phase of the digester, is useful or not is analyzed. For the samples to be useful, there has to be a relationship between the measured Kappa at the mid- phase and the measured Kappa in the blowpipe at the bottom of the digester. An ARX model of the lower part of the digester has been estimated.

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.

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