At SIA TallOil's pellets factory in Latvia wood shavings and saw dust are dried with flue gases from a gas burner. TallOil wants to replace the gas with a biofuel that is available at the pellet plant. The reason for this is the unstable gas market in Europe in combination with the fact that TallOil wants to improve its profile as supplier of renewable bio fuels. In this project the technical and economical possibilities for a fuel conversion to ether bark powder, wood shavings or wood powder have been investigated. These fuels should be burned in one of the following applications: TPS BioSwirl, VTS Multifuel burner or Saxlunds bio fuel combustion plant Due to the fact that the fuel alternatives available are relatively common except for bark powder, the work has mainly been focused on bark powder.

With higher prices for oil and increased focus on fossil fuels impact on the environment the heating sector are searching for alternative fuels. Pellets are a quite new product whose production has risen exponential in recent years. Today there are small-, medium-and large-scale users, where the large-scale consumers are the heating sector. The heating sector is mainly using oil to cover the increased demand during cold periods. The purpose of this study is to analyze the potential of pellets if it would replace thermal power plants oil and coal. The study will also analyze the economic impact a conversion would mean for a heating plant and if the pellet is a reasonable substitute. 2008 statistics from the Swedish district heating association were analyzed and a calculation was performed to determine how many tons of pellets is needed to replace coal and oil.

This examination work aims to describe how a supply chain around the biggest pellets factory in Sweden will be configured in a logistic perspective. The plant and associated infrastructure are in the building phase and will have production start on the 2 November 2009. The key question that is set in this examination work is to recognize the logistic processes which are essential for an effective flow of materials and information that link the source of supply with the ultimate customer. In order to get the answer, a flowcharting of these supply chain processes is required for understanding the pipeline activities such as input and storage of raw material, the production system and the output of pellets to the customers. The basis for this supply chain map is a model-based representation of these logistic processes and activities that are involved around the pellets factory.

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.

With the elevated oil prices of today it is necessary to look for other heating alternatives. If the oil price continues to develop in the same way it has done the last years it will soon be impossible for many producing garden companies to survive. The purpose of this diploma work is to compare three different fuel options in order to find the most economic one considering the conditions of Katrinebergs Handelsträdgård AB. In relation to oil it is profitable to change to any of the three alternatives: wood chips, wood pellets and grain. The most profitable option is to change to wood chips. This alternative has a payoff time less than three years and after that the annual saving compared to the oil is relatively high. The annual cost is 65 % of the cost of the oil alternative.

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.

This report summarizes the development of a calculation program estimating the profitability of converting a peak-load oil-fired boiler to pellets. To convert an oil-fired boiler to pellets a new fuel handling system must be designed. Changes also have to be made to some other components. Since there are many different techniques for transportation, storage and treatment of the fuel only the most interesting techniques from Swecos experience and interest were included in the study.The capacity of the different parts in the system was dimensioned based on the power of the boiler after conversion. To estimate prices, installed power and dimensions manufacturers and distributers were contacted.

The Swedish production of biogas was 1,5 TWh 2011. About half of the production was used as vehicle fuels. The cost for upgrading biogas depends on the size of the biogas plant and its gas production. If the gas flow is low the cost will be high. However, further development of existing upgrading technologies or development of new ones, have good potential to decrease the upgrading cost for small scale biogas plants.

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.

Detta examensarbete har utförts vid LKAB:s FoU-avdelning i Luleå och vid LKAB:s metallurgiska laboratorium i Malmberget. LKAB har en världsledande position som producent av järnmalmsprodukter till stålindustrin. Huvudprodukten är magnetitbaserade pellets för råjärnsframställning i masugnar och direktreduktionsugnar. En förutsättning för en jämn och hög masugnsdrift är en god gasgenomströmning med ett lågt tryckfall. Abnorm svällning av pellets medför minskad porositet i pellets och minskade hålrum i beskickningen, vilket har en negativ inverkan på gasgenomströmningen.

This examination work brings up opportunities to invest in a construction for heating with grain or pellets on farm level. As example we have chosen Fröberga Gård which is a farm located in Östergötland outside of Söderköping. The farm`s residential buildings is to day heated with oil and electricity. The result of our investigation shows that heating with grain is the best alternative, partly because of economical issues but also because you can grow the grain on your own farm and by that you can get better economy in your seed cultivation. To grow 16 tonne of grain as is needed demand gives a insignificant increase of work. Further an advantage is that no investment in machines is needed because all the machines witch is needed already is in use on the farm. In a situation where a new investment is needed as in the case we studied, is it often profitable to invest in a integrated furnace. Because all the components are well adapted to each other, and because that gives a high efficiency. If you already own a well working furnace is it often most profitable to connect a burner to it. It is important to know that heating with grain need more work than heating with pellets, because the high contents of ash in grain. Even if you choose pellets instead of grain the calculation shows good results. Because peat is an excellent but fairly untested raw material for pelletsproduction we have chosen to watch little more on its quality and conductions. We discovered that peat has a high heating value which makes it possible to raise the heat value in pellets through mix up peat and wood. Or you can make pellets with only peat and get a pellet with high heating value. Even the calculation with peatheating shows good results..

Idag a?r fossila bra?nslen fortfarande de fra?msta energika?llorna runt om i va?rlden. Enligt ma?nga experter kommer snart inte produktionen kunna tillfredssta?lla efterfra?gan av olja. Da?rfo?r bo?r o?verga?ngen till alternativa bra?nslen ske sa? fort som mo?jligt.

The project focus on combustion of softwood pellets and pellets in a 40 kW grate fire reactor at TEC-Lab. Dept Applied Physics and Electronics at Umeå University. Experiments were performed at four primary airs to fuel ratios (0.7 to 1.3), where aspects such as temperature profile, levels of gases (CO and NO), sintering-/-slagging and unburned fraction of the ashes were studied. Four different fuel loads were used for wood pellets (10, 20 and 30 kW) and one fuel load for straw (10 kW). Combustion of straw proved very difficult to ignite, and also led to other combustion-related technical problem such as slag formation due to the relatively low melting temperature-/-slag temperature of the straw.

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.

Every year about 210 000 tones dry weight of sewage sludge is produced in Sweden. Most of the sludge is applied to agricultural land, plantsoil and landfill cover. Sewage sludge contains essential nutrients such as nitrogen and phosphorus. Nitrogen is limiting growth on solid ground in Sweden and can therefore be used as fertilizer to increase productivity. In order that the sludge can be spread to forest land it requires first a conversion of sludge to pellets, to make it more manageable.