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40 Uppsatser om Bioenergy - Sida 3 av 3

Torrefaction of biomass : a comparative and kinetic study of thermal decomposition for Norway spruce stump, poplar and fuel tree chips

Stump biomass is energy rich and stump harvesting for use as fuel become more and more interesting in Sweden. Swedish Forest Agency (2009) has estimated that stump harvesting in Sweden would respond to an annual energy supply of 57 TWh/year. However, stump has not been recognized as a Bioenergy resource in Sweden. Suitable methods for pre-treatment of stump are probably of great importance to make it accepted as fuel. It is therefore rewarding to carry out an investigation in this area for stump. This report represents results from a diploma project, which was aimed to develop a fixed bed reactor for experimental study of biomass torrefaction, followed by TG analysis and kinetic modelling employing Ozawa method and different kinetic models including one-step and three-pseudo-component models.

Kolbalansen vid olika skötselstrategier för skogen på Tagels fastighet.

Since the 19th century the concentration of CO2 in the atmosphere hasincreased by 40 percent as an effect of the use of fossil energy sources.Increased concentration of CO2 will likely lead to increased temperature,changes in precipitation, rising sea level and increased frequency of extremeweather like storm events. A step to reduce emissions of CO2 and mitigateclimate change, for the property of Tagel, can be to adopt new silviculturalstrategies and analyse which is the most effective. As a result of that, threescenarios was produced, business-as-usual (BAU), increased set aside landand energy. An introduction of windpower at Tagels estate (property) andeffects on carbon balance was also examined. By using the Heureka systemand LCA-analysis in this study, it showed that the scenario of increased setaside land was the most efficient way to reduce carbon dioxide (CO2)emissions for the analysed period of 100 years.

The effect of new raw materials on pellet prices

As demand for renewable energy is increasing rapidly, the market for biomass pellets is expected to continue to grow in the near future. Most of the new raw materials that are discussed for pellet production have one thing in common; the production costs will increase compared to using traditional raw materials such as sawdust and planer shavings. The aim of this thesis is to investigate to what degree increased use of new raw materials for pellet production will affect the general pellet prices in Sweden and to survey what plans Swedish pellet producers have concerning new raw materials. To investigate the raw material situation of the Swedish pellet producers an industry survey was performed. Literature studies were also made on previous research in the subject field. Calculations of the production costs for pellets were done for the raw materials sawdust, wet sawmill chips and energy wood respectively. New raw materials are already used by the large-scale pellet producers in Sweden.

Träpellets: en växande affärsmöjlighet : Produktion av träpellets i Brasilien för export till Europa

Titel:Träpellets: en växande affärsmöjlighetProduktion av träpellets i Brasilien för export till EuropaNivå:       D-uppsats i ämnet företagsekonomiFörfattare:            Susanna TosterudHandledare:                     Jonas KågströmDatum:                          2012 ? JuniSyfte:                                                   Syftet med denna studie är att undersöka de ekonomiska förutsättningarna som finns att tillverka pellets i Brasilien för export till Europa.Metod:      Studien har använt en kvalitativ metodansats där datainsamlingen för empiriavsnittet består främst av semistrukturerade öppna intervjufrågor, som skickades till respondenterna via mejl. Sedan skedde kontakt via telefonsamtal för att säkerställa att informationen var korrekt uppfattad. Respondenternas svar redovisas i empirikapitlet och har analyserats och bearbetats med hjälp av två teorier inom marknadsföring, nämligen marknadsföringsmix (de 4 P: na) och SWOT-analys.Resultat & slutsats:                              Resultatet visar att i nuläget är det inte lönsamt att exportera pellets från Brasilien till Europa. Priserna för pellets på den europeiska marknaden är för låga, en höjning med cirka USD 50/ton är nödvändig för en godtagbar lönsamhet.

Lantbrukaren som energiproducent : en fallstudie i energisatsningar inom lantbruket

The intrest and development of Bioenergy and energy from renewable sources in Sweden has increased rapidly over the last few years. There are a whole lot of alternatives for those who would like to venture and invest in renewable energy production. Production of renewable energy opens up many opportunities for forestry and farming to venture a new branch of production, on basis of the primary production. Several of the new energy sources grows on farmland or in the forest. The opportunities exist in the primary products, as well as in refining and reselling, in the value chain of energy. The starting-point is the Farmer as an energyproducer. This master thesis studies the nature of farmer-own firms, who has invested in production of renewable energy.

Mekaniserad ungskogsbehandling för röjning och skörd :

Earlier attempts at mechanising pre-commercial thinning have been met with varying degrees of success. Most attempts have been based on techniques where residual stems are straddled. Early treatment is essential to limit damage on residual trees. One part of the present study is an evaluation of mechanised pre-commercial thinning using the new Vimek 404R. Vimek 404R is a fairly small machine that permits selective removal of stems, making it potentially suitable also for areas overdue for pre-commercial thinning. The study established the level of performance for the machine, as well as the improvement needed to make it an economically viable option.

Förutsättningar och Avsättningar för Biogas för Gröna Vessigebro : Version 1.0

The community Vessigebro, in Falkenberg and its surrounding areas housing one percent of all dairy cattle and two percent of all pigs in Sweden. This means that there is a large amount of manure as a basis for producing biogas in the area. A number of farmers have therefore formed a cooperative named Vessigebro biogas and started the project Green Vessigebro, with the goal of creating the conditions for a more profitable and more sustainable agriculture production.The study deals with the conditions and sale opportunities of the feasibility study Green Vessigebro. The study has looked at the work that was previously carried out for the biogas that could be produced on the farms in Vessigebro, The main pipeline for natural gas on the Swedish west coast and its operators, the Swedish Competition Act , Electricity Act , Natural Gas Act, the District Heating Act , Sustainability Act , previously proposed measures, municipality interest in biogas from Vessigebro , possible collaborations, possible sale opportunities and perform calculations with data from the municipality Ljungby for a suggested transportation of biogas between Vessigebro and Ljungby.The study shows that there are several interesting sale opportunities for biogas from Vessigebro. The production and use of biogas in Sweden is increasing and the trend seems set to continue.

Produktivitet vid stubblyftning :

Stump wood was used between 1850 and 1950 for production of tar and as firewood. In the 1950s the use decreased because of the introduction of the cheap fossil oil. In the 1970s stump wood became an interesting issue again as a raw material for the pulp industry. Stump lifting has today become a possible source for Bioenergy. The objectives with this study were to investigate the productivity of stump lifting and stump extraction, and to analyse the economy.

The state of the Latvian wood pellet industry : a study on production conditions and international competitiveness

In the last decade, member states of the European Union have adopted a range of measures to decrease the dependency on fossil fuels. This has led to an increased use of biomass in heat and power production. In some countries, the lack of forest resource has led to large scale power producers importing their biomass needs. Due to high energy content and homogeneity, wood pellets have become an internationally traded commodity used for large scale power production. The Baltic States have emerged as one of the largest wood pellet exporting regions in Europe.

Biogallring : effektivitet och lönsamhet vid gallring i ung skog

I Sverige har sedan mitten av 1990-talet antalet bestånd där röjning inte utförts ökat. Dessa bestånd är åldersmässigt mogna för en första gallring men pga. utebliven röjning är de mycket stamtäta och dimensionerna är klena vilket gör att valet av skötselåtgärd inte är självklart. De senaste åren har intresset för uttag av biomassa även i unga skogar ökat. Under våren/sommaren 2009 startade Stora Enso Skog (SES) ett fullskaleprojekt där syftet var att testa en gallringsmetod med flerträdshanterande skördaraggregat och uttag av (förutom rundvirke) ett bioenergisortiment (träddelar/okvistade toppar) i eftersatta röjningar och tidiga gallringar.

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