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104 Uppsatser om Pellet mills - Sida 1 av 7

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.

Cassava as an additive in biomass fuel pellet production :

In this study, the effects of using fine milled cassava stems as an additive in biofuel pellet production was compared to the effects of refined starch addition. The bulk biomass fuel raw material, to which the additive was added, was a blend of spruce and pine sawdust. An experimental design in the factors cassava/starch content, moisture content and material temperature was used. Measured responses were pellet bulk density, pellet durability, amount of fines, pelletizer motor current, pellet temperature, die temperature and CV for pelletizer motor current (a measure of process stability). Each response was modeled by multiple linear regression (MLR).

Integrering av pelletsfabrik med Rya kraftvärmeverk i Göteborg : en teknisk och ekonomisk utredning

Göteborg Energi has a surplus of district heating during spring, summer and fall. The heat surplus is due to a constant production of waste heat from oil refineries and heat from waste incineration over the year. It would be desirable to increase the demand for heat and the uptime for the newly built combined heat and power generation plant, Rya Kraftvärmeverk. One alternative could be to integrate Rya Kraftvärmeverk with a pellet production facility. By producing heat, electricity and pellet in a joint process the energy use can be decreased.

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.

Pelletring som marginalaffär för mindre sågverk/hyvlerier : en studie av 5 anläggningar i Småland

Denna studie handlar om pelletering som möjlig lönsam marginalaffär vid mindre sågverk/hyvlerier. Studien, vilken skett genom djupintervjuer på plats, omfattar fem olika mindre sågverk/hyvlerier i Småland. Verksamheterna är sinsemellan på många sätt olika men har samtliga satsat på pelletering av ekonomiska skäl och av miljöskäl.Studien visar att pelletering är lönsam men också att det krävs vissa förutsättningar för att långsiktigt nå denna lönsamhet. Den viktigaste är långsiktig tillgång till råvara i form av torrt spån men det krävs även ett genuint intresse och en stor kunskap inom såväl teknik som trä för den som skall pelletera Detta beror på att produktionsprocessen är mycket komplicerad och även beroende av en del yttre omständigheter som t.ex. fukt, kyla och torka.

Pelletskvalitet : Test av olika råvarumixer i pelletstillverkningen vid Rindi Västerdala AB:s bioenergikombinat i Vansbro

Fuel pellets are a refined bio fuel mostly consisting of residues from sawmills and wood industry. At Rindi Västerdala AB's combined bio energy plant in Vansbro fuel pellets are produced, while the waste heat from the process is used for district heating. The pellets are produced from sawdust, wood shavings and dry wood chips that is dried, milled and pressed into small cylindrical rods. The advantage of refining the wood material in this manner is that the energy value is greater per unit volume and unit weight, thereby the cost of transportation per energy unit is reduced. Also, less storage space is needed.Pellet manufacturing is a complex process since many parameters affects the final results.

Förbränning av pellets framställda av defibrerad granråvara :

Fuel pellets are in Sweden mainly produced from sawdust and cutter shavings. Before the pelletising process the raw material is dried to attain consistent moisture content and ground up in a hammer mill. In the densification process (pelletising) the ground material is forced through holes in a rotating die. This heats up the wood particles which cause them to soften and self bond. After the process the pellets are cooled, sieved and bagged. The milling process creates a wide range of particle sizes.

Om stenar kunde tala : arkeologiska rön och bebyggelsehistorisk kontext av kvarnstensbrottet Östra Utsjö i Malung

This paper deals with village history around millstone quarry Eastern Utsjö in Malung, Sweden, in the hope of finding deposits that could date the quarry, in that the quarry in the current situation is dated only by the millstone fragments outside the resort. My purpose was to conduct a discussion on the quarry alone can be dated by deposits outside the resort. I have used FMIS RAÄ:s fornsök and a lot of literature to identify village history. The results showed that it is not possible to date the millstone quarry from village history, but through deposits outside the resort of Malung, which have been found around Mälardalen, Sweden through archaeological excavations, and derived from the millstone quarry Eastern Utsjö, can put an age on the quarry..

Medvind eller motvind? : granskning av fem tillståndsansökningar från vindkraftprojektering i Sverige

The Swedish Government has decided that Wind power should have a higher contribution to the electricity generation in Sweden. Their goal is that, by 2015, the yearly production by Wind power should generate 10 TWh. In year of 2006, the 760 wind mills in Sweden generated only 0,936 TWh. Despite good wind conditions in a large extend of Sweden's land- and coast areas, the slow rate of new wind mills establishments will likely result in unattainable goals. The major problem for new establishments of wind mills is the extensive and complicated permission process. An expert group of environmental studies (Expertgruppen för miljöstudier) was commissioned by the Government to make a report concerning the problems with the expansion of wind power in Sweden.

Rissepareringens effekter på viltets nyttjandegrad av GROT

Successful forest regeneration is a prerequisite for sustainable forest management. Therefore, it is important to prevent browsing damage on the commercially important tree species Scots pine. In this study I have tested a new alternative way to increase the available amount of forage and increase the use of these resources by especially moose. The method is based on a slash treatment at harvest, where the accessibility of slash as forage is increased during final felling or commercial thinning by gathering the slash and putting the Scots pine slash on top of the slash piles. This study has compared the availability of forage, the amount of browsed biomass and the number of fecal pellet groups between conventional and slash treated stands after final felling and commercial thinning in southern Sweden.

Småhuset ? val av bergvärme, fjärrvärme eller pellets

This thesis describes the new construction of a small house and it includes studies of three heating systems: geothermal heating, district heating and pellet. The purpose of this thesis is to project a small house which can manage Building Regulations, BBR conditions and then examine three possible heating systems for the small house. This thesis is a literature study which gives an understanding of the heating systems technical structure, properties and costs. An empirical study completes the literature study by giving a deeper understanding of district heating costs and pellet costs. The empirical study contains two interviews, one of which was conducted in a district heating corporation and the other interview was conducted in a pellet corporation.

Kvalitetsprocesser och mätning av pinnfräsar : ? Empirisk studie av produktionsmätutrustning vid frästillverkning

This master thesis investigates quality procedures and measuring of solid carbide end mills, with the main focus on measuring equipment. The thesis has been written in collaboration with a special production department for solid carbide end mills at Sandvik Coromant in Gimo. The department?s needs and constraints have been the foundation of the project and the main research question is: how to measure end mills in order to ensure good quality of the produced end mills. The project has contained both a theoretical study consisting of a literature review and practical studies in the workshop with the objective to identify an end mill?s main parameters and the relationship between an end mill?s geometry and the manufacturing processes.

Varför vill ingen bli musiklärare i högstadiet?

Syftet med denna uppsats är att undersöka om Karl Marx och Wright Mills teorier om alienation går att koppla till en högstadiemusiklärares arbetssituation och hur denna koppling i så fall ser ut. Eftersom tankarna och teorierna om alienation berör mångt och mycket så har jag valt att behrönsa teorianvändningen till två perspektiv som jag kallar det ideala arbetet(från Karl Marx) och alienation som diskrepansteori(från Wright Mills). Dessa teorier har i sin tur omformats till hypoteser för att underlätta analysen. Metoden som jag har valt för denna undersökning är samtalsintervju och jag har intervjuat fem musiklärare verksamma på högstadiet. Ur undersökningens resultat och analys framgår det att det i stora drag finns fyra orsaker till en potentiell alienering: viljan att lära känna eleverna, betygssystemet och kursmålen, de skriftliga omdömena och arbetsbördan.

Utveckling av ny produktfamilj med handskar för användare inom street- outdoor segmentet. : En liten bit av naturen till staden, en liten bit av staden till naturen

This thesis describes the new construction of a small house and it includes studies of three heating systems: geothermal heating, district heating and pellet. The purpose of this thesis is to project a small house which can manage Building Regulations, BBR conditions and then examine three possible heating systems for the small house. This thesis is a literature study which gives an understanding of the heating systems technical structure, properties and costs. An empirical study completes the literature study by giving a deeper understanding of district heating costs and pellet costs. The empirical study contains two interviews, one of which was conducted in a district heating corporation and the other interview was conducted in a pellet corporation.

Lönsamhetsanalys av tekniker för utökad elproduktion i kraftvärme : Med hänsyn till elprisets variationer

This thesis aims to examine the viability of various techniques for increased electricity generation in CHP plants and the effect of electricity price fluctuations on the profitability.The techniques examined are fuel dryer, pellet production, methane production, combined methane- and pellet production, seasonal heating storages in caverns and pit heat storages and condensing tail. Using Excel and Matlab, the prerequisites for investment costs, revenues and expenses were calculated.What affects the price of electricity is a combination of economic and technological development, energy prices, economic structure, population changes and weather. Different scenarios for the electricity price were therefore examined. In the base case, the electricity price was given by the Nord Pool electricity price statistics of area three in 2011. Thereafter, WiMo was used to design the electricity scenarios for 2030, which was then applied to the data to obtain the viability of various scenarios. The techniques examined were found to give greater profits to the CHP plant by increasing and optimizing the production of electricity.

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