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882 Uppsatser om Pre heating of wood chips - Sida 2 av 59
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.
Systemanalys av skogsbränsletransporter :
At the end of 70s and the beginning of 80s, 18 terminals was built and used for chipping wood residue from clear cuttings. Most of the terminals was terminated before the 2000s but with the high oil- and energy prices that we can see today there might be a place for these terminals again. The goal with the study was to analyze and compare economical differences between 5 different logistical systems, collected data was used with a set of formulas. The systems include long range transport of slash, chips and bundles. Three of the systems include transport by lorry to industry the last two includes a terminal with access to train transport.
Modellering och styrning av flis till en sulfatkokare
At the Skoghall pappermill, sulphatepaper pulp is produced in a continuous digester originally from 1969. To be able to maintain a high level of production there is a need for a process with few disturbances. Variations in how well the wooden chips are packed in the digester is one form of disturbance. Today there are no available measurements on how well the chips are packed. Instead this is regarded as being constant.
Stubbtransporter och bränslekvalitet hos stubbved :
Stump wood is a hot alternative when the heating plants demands more and more forest fuel. The aim with the study has bean to calculate the costs in four different systems for transportations of stump wood, examine if there are any differences in fuel quality for the stump wood in the different systems, analyse if the fuel quality in stump wood is affected with the time it lays by the road side and how much space the stump wood demands on the road side. To calculate the costs for the different systems a system analysis was carried out, where some of the costs were collected through field studies on Holmen Skog stump experiment and other costs were collected from literature and contacts. Data for the fuel quality study was collected from Eons heat plant in Norrköping. Data for the study of how much space stump wood takes along a roadside was collected from field studies.
Biomass losses during short-term storage of bark and recovered wood
Storage of biomass is associated with problems like heat development, biomasslosses, and reduction of the fuel quality. Certain processes such as biological- andchemical degradation are responsible for these storage problems. This master?sthesis was carried out at Vattenfall Research and Development AB and is alignedtowards quantifying the biomass losses from short-term storage (1-2 months) ofbark and recovered wood. The biomass was stored in outdoor piles during differentseasons, campaign 1 (summer) and campaign 2 (autumn).
Pellets - en framtidsmarknad?
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.
Passivhus av helväggselement i träull
Environmental destruction is a growing problem in our world. Almost every day there are new reports concerning that we have to do something about the greenhouse gasses. Simultaneously is the human constantly more eager to have a life with higher standards and therefore uses more energy. The environment is a question that is highly up-to-date and more people try to find solutions on how to save our planet. One way to decrease the energy demand is to build passive houses, where the houses don?t have any active heating.
Automatisk tändning till modern vedpanna
If you have access to wood, a wood burning boiler is a cheap way to heat your home, but it is certainly not the most convenient option. Wood requires many operations and management, which takes time. One way to reduce this workload is to have a modern boiler with automatic ignition. Enertech/CTC has a desire to create an accessory with automatic ignition to a modern wood burning boiler. Today there is no boiler on the market that can ignite firewood automatically without the introduction of paper and sticks.
Logistik för stråbränsle :
Summary
Today energy prices are rising. As a result biomass fuel is getting more and more
interesting. Wood chips is very popular, but also straw from grain production is on the
table. Lunds Energi AB project a combined power and heating plant in Örtofta out of
Lund. Wood chips is meant to be the main energy source, complemented by straw.
In this thesis the transportation of straw for fuel is studied.
Uppvärmning med spannmål och trädbränslen :
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..
Energianalys av etanolproduktion : en fallstudie av Lantmännen Agroetanols produktionssystem i Norrköping
In this thesis an energy analysis of ethanol production at the ethanol plant of
Lantmännen Agroetanol in Norrköping has been performed. The ethanol plant has
been studied in combination with Händelöverket, the combined heat and power
plant which provides the ethanol process with steam. The purpose of this study
was to determine the energy consumption for the whole production chain from
grain to ethanol. The analysis has included the energy consumption for cultivation
of grain, production of chemicals, the production chain for wood chips, the steam
production and the ethanol plant. The grain and wood chips are both considered
raw materials there for the energy content in these are not included as energy input
in the system.
Energianalys av etanolproduktion : en fallstudie av Lantmännen Agroetanols produktionssystem i Norrköping
In this thesis an energy analysis of ethanol production at the ethanol plant of
Lantmännen Agroetanol in Norrköping has been performed. The ethanol plant has
been studied in combination with Händelöverket, the combined heat and power
plant which provides the ethanol process with steam. The purpose of this study
was to determine the energy consumption for the whole production chain from
grain to ethanol. The analysis has included the energy consumption for cultivation
of grain, production of chemicals, the production chain for wood chips, the steam
production and the ethanol plant. The grain and wood chips are both considered
raw materials there for the energy content in these are not included as energy input
in the system.
Fjärrvärme - ny lokalisering av kraftvärme i Enköping
The municipality of Enköping is presently working out a new layout plan for the town of Enköping and new residences are planned in the harbour area. Because of these plans, the municipal energy company ENA Energi may have to move its location from the harbour to another part of the city.The aim of this degree project is to investigate the possibility of building a new CHP plant in another area of Enköping. The future demand on district heating and infrastructure at the new location have been projected. A new CHP plant has been dimensioned and economic analyses concerning the project have been made.Results show that the future demand of district heating in Enköping will differ a little from the present needs. In 2030, the district heating production is expected to be c.
Uppgradering av biogas med aska från trädbränslen
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.
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).