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15 Uppsatser om Sawdust - Sida 1 av 1

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.

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.

Torvströ till svenska mjölkkor :

Peat litter is a soft material with high absorbency. About hundred years ago many farmers in Sweden used peat litter to their dairy cows. After the World War II the use of peat litter decreased and the farmers used more straw. Nowadays (year 2007), when it is harder to find straw and Sawdust to buy, peat litter is advancing again. The purpose with this study is to investigate peat as a litter to dairy cows.

Fermentation of lignocellulosic material by the alternative industrial ethanol yeast Dekkera bruxellensis

Bioethanol is one alternative energy fuel that can be produced from different types of biomass. Second generation bioethanol comes from fermentation of lignocellulosic material and can be seen as a more environmental friendly alternative as e.g. forest residues and agricultural by-products are used. To be able to use lignocellulosic biomass in ethanol production, it has to be subjected to different treatments first. In this study, aspen Sawdust was used as lignocellulosic material.

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.

Strötorvsanvändning i djurstallar : en litteraturgenomgång

Peat litter has been used in animal houses for a long time. Because of its good ability to absorb liquid and nutrients from the manure it can create a dry surface for animals and a valuable manure product. Through changes in agricultural practises the use of peat litter has diminished and is to a great extent replaced by straw, Sawdust and cutter shavings although Sweden is rich in peat-findings. The aim of this work was to summarize the presented knowledge about the used of peat litter, techniques, advantages and disadvantages and to compare with other commonly used litter materials. Articles on peat litter have been searched for in magazines, databases and books at SLU library. Visits to peat industries, interviews with peat producers and with peat researchers contributed to the material. Peat is not a uniformly material.

Kartläggning av spånprodukter vid Sävar såg

A change towards using more biofuels than fossil fuels is taking place in Sweden, and in many other parts of the world. This makes the use of fuel pellets increasingly popular, causing a greater demand for sawmill Sawdust products. There is a trend towards the use of multiple types of shredders, instead of a single type in each sawmill. The purpose of the study was to characterize the different flows of saw particles that can be found at Sävar såg when cutting thick or thin wood with different cutting techniques. The saw particles size, shape, moisture content and heat value were analysed by the cutting stations: first cutting fast and slow, second cutting fast and slow, grading fast and slow and planning.

Bakterietillväxt i strömedel till mjölkkor

The resting area is the most important place in the barn for the dairy cow, sometimes called the heart of the free stall system. Inadequate design of the lying area, and lack of or poor quality of bedding materials may reduce the hygiene of the stall. Poor management regarding the cleanliness of the resting area may lead to poor animal hygiene and increased bacterial growth. This in turn will lead to increased risk for environmental mastitis as well as impairing milk quality through contamination with spores. In this literature study the most commonly used bedding materials; straw, Sawdust, wood shavings, clean sand, recycled sand, peat and recycled manure solids, are compared to one another with regards to their ability to resist bacterial growth. Effects of adding hydrated lime to bedding materials have also been studied. Most bacteria need humidity and prefer a quite high water activity to be able to grow.

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).

Dimensionering av industrilager för biobränsle :

The aim of this study was to develop a simple model for calculating stock costs for bio fuel at Billerud Karlsborg and subsequently recommending a suitable stock level of bio fuel. The stock components considered in the model are GROT (branches and tops), bark, dry wood chips, raw wood chips from barking and Sawdust. The calculations are based on a probability distribution of historical deviations between ordered and delivered volumes. The model presents two different ways to manage the supply in case of irregular deliveries. The first way is to stock enough volume to cover the deviations and the second way is to compensate with a quick purchase from the spot market (at extra high purchase prices).

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.

Bois Durci : Ett designprojekt inom 5 mil

Människor förbrukar så mycket resurser att natureninte hinner med att återställa sig och där medförsvinner material allt mera. Det bästa vore om vimänniskor enbart använde oss av material som förbrukadesi samma takt som naturen kan återställa dei.Detta designprojekt fokuserar på Bois Durci, pådess tillverkning och användning. Materialet ärgjort av blod och sågspån och var tillgängligt på1800-1900-talet och försvann när bakeliten kom. Detsägs att materialet är bakelitens fader. I arbetet harjag samarbetat med ett företag från Torsåker i centralaSverige och arbetet utefter deras koncept somgrundar sig i att enbart använda sig av råvaror inomen femmilsradie.Arbetet har utgått från frågeställningen ?Kan BoisDurci tillverkas inom en femmilsradie och hur kanjag som designer ta mig an materialet?? Att användasig av en femmilsradie med utgångspunkten frånTorsåker var inte ett problem, det var enkelt att få tagi både blod och sågspån.

Hållning av kastrerade och icke kastrerade försöksmöss i par som en lösning på aggressivt beteende

Aggression between laboratory mice is a common problem and can result in welfare issues such as mice hurting or killing each other and also stress. Swedish laws and regulations clearly states that mice must be housed with a companion due to their natural social structure. Many studies have investigated the effect off enrichment, group size, cage size and other potential changes in in their environment on the occurrence of aggression. Even with these changes aggression can exist and therefore a new solution was tested in this paper. The proposed solution was to house an intact mouse with a castrated one and thus fulfill laws and regulations while still maintaining the physiology of one of the mice for the purpose of medical experiments.

Utvärdering av prestanda för en pneumatisk tork : Praktisk mätning av en pilotanläggnings torkningseffektivitet

Biomassa är en växande energikälla i samhället. Biomassa så som sågspån behöver ofta torkas och pelleteras innan det kan användas som energikälla vid förbränning. Sågspån torkas innan pelleteringen för att kunna ge ett bra värmevärde och för att kunna förbrännas utan ökade halter av utsläpp. I takt med ökad användning av detta bränsle finns det en ökad efterfrågan på energieffektiva torkningsmetoder. På Karlstad Universitet har det därför byggts en pilotanläggning av en pneumatisk tork med syfte att fungera som ett steg i en energieffektiv torkningsmetod kallad ?Two Step Drying Technique? eller TSDT.Det här arbetet har handlat om att utvärdera effektivitetsmått och driftinformation för torken på Karlstads Universitet.

Bestämning av tryckfallet vid pneumatisk transport av sågspån : Genom simulering och praktiska försök

Minskad tillgång på fossila material och ökade energibehov i värden skapar ett behov av att utveckla alternativa och miljömässigt hållbara lösningar. Biobränsle har därför växt till en av de viktigaste förnyelsebara energikällorna i målet mot ett koldioxidneutralt samhälle. Dock skapar det obearbetade biobränslet problem, på grund av den höga fuktkvoten, mellan 50-150 %. Som en följd finns ett torkbehov som måste lösas på ett miljö- och energieffektivt sätt. Idag står torkningen av biomaterial innan pelletering för 25 % av den totala kostnaden vid pelletstillverkning.Kostnaden för att torka biomaterialet gör det viktigt att effektivisera torkningen, samtidigt bidrar torkningen till utsläpp av miljöfarliga ämnen såsom terpener.