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882 Uppsatser om Pre heating of wood chips - Sida 46 av 59
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.
Energi - och ekonomipotential för solceller i Hållbara Järva
One of the city of Stockholm?s main objectives is to have a society completely free from fossil fuels. To achieve this, several investments regarding improvements in energy efficiency and renewable energy are currently being planned or implemented. One of these investments is a project called Hallbara Jarva which is located in the suburbs of Stockholm. The purpose of this thesis is to examine the prospects of an investment in photovoltaic cells from an energy-saving and economical point of view. The analysis is limited to three buildings within Hallbara Jarva and is intended for the property owner. Solar energy is a type of renewable energy source and is commonly divided into solar heating and solar power.
INFÄSTNING AV LED-ARMATUR
The thesis was performed at the lighting company Zpecta AB. Zpecta needed to develop alternative attachment of their LED-luminaire Capella. Today Capella attaches in metal ceilings with four magnets. Zpecta got indications from their customers that there was a need for other attachments. The purpose is to determine the customer?s requirements and the interfaces that are considered for Capella.During the thesis, Capella was only on the market for testing and evaluation.The thesis was initiated to create a specification.
VVA-strategier för avgastemperaturhöjning på en HD-Dieselmotor
Regulations on the exhaust emissions of HD-diesel engines are becoming more and more stringent, and therefore, emission after-treatment systems are commonly used. These systems rely on catalytic conversion of NOx,CO , and HC emissions, and are thus dependant on temperature. At low load of the engine, exhaust temperatures are not sufficient for the after-treatment components. Therefore, means to increase the exhaust temperature while maintaining low emissions and fuel consumption are needed.The focus of this project has been to develop strategies for the lift profiles of exhaust and intake valves in the engine, with the goal to raise exhaust temperature in combination with low emissions and fuel consumption. The strategies have been tested in a single-cylinder research engine equipped with a hydraulic variable valve actuation system.
Barkar det åt skogen för svenskt tidningspapper? : empirisk analys av efterfrågan och företagsstrategier på den svenska marknaden
According to Food and Agriculture Organization newsprint is defined as: Uncoated paper, unsized (or only slightly sized), containing at least 60 percent of mechanical wood pulp. The consumption of newsprint in Sweden was just over 798 000 tonnes in 2009, which represents approximately 90 kg per person. Although there are studies that predict a drastic reduction in newsprint consumption in the Western world, there seems to be a clear difference between forecasts for the future given by statistical analysis of newsprint consumption and forecasts given by experts in the industry. The former predict a continuing increase while the experts see a coming decrease in consumption.In this report, both demand and business strategies of newsprint in Sweden are studied. The study also presents a forecast of the future which is based on historical data and qualitative interviews.
Ekonomi i Passivhus : En studie av två verkliga byggnader
The aim of this report was to investigate the economy of passive houses. The work was focused on economy in total and on the economy of different components such as windows, insulation, heat exchanger and the air tightness of the climate shell. No attention was paid on the comfort factor or to the impacts on the environment.Two houses, aspiring to be passive were chosen; A big one and a small one. Hence, comparisons considering the size of the building have been possible to do as well.The comparisons were made by calculating ?break even? between two concepts; passive and BBR- concept.
Identifiering av konfliktbestånd med hjälp av laserskanning
The interest in harvesting wood fuel in conflict stands has grown in recent years as a consequence of the increased demand for biofuel. Conflict stands are young forests that have not been cleaned and have a large number of stems ha-1with a great height and diameter distribution. This means that traditional field measurements in conflict stands are difficult and very time consuming. Therefore, the forestry sector is in need of new, more efficient inventory methods. In this study, the Lidar data from Lantmäteriet?s (the Swedish mapping, cadastral and land registration authorities) new national height model was used in combination with plots from the Swedish national forest inventory from 2009 to create functions for; height, volume, diameter and number of stems.
Energianalys av Svensk Växtkrafts biogasanläggning i Västerås
Svensk Växtkraft is the owner of the biogas plant in Västerås. The company is planning to increase
their treatment capacity at their biogas plant. In connection to this work it is also possible to make
some energy saving changes to the biogas plant. The objective of this study was therefore to make
an electricity and heat survey of the biogas plant, a detailed study of the heat consumption in the
sanitation step and also a comparison of energy consumption with the present sanitation method
and an alternative strategy where the waste is treated in 55 °C during 10 hours (the current method
is heating to 70 °C during 1 hour).
The energy survey was conducted in close collaboration with staff at the biogas plant. The current
during normal operation was measured, power was calculated and multiplied by the time of usage to
obtain the energy consumed.
Effekter av gödsling i äldre tallbestånd på renbetesväxter i fält- och bottenskikt :
Reindeer husbandry and Forestry are both area related industries and will in big extent use the same lands. Conflicts often arise because of that the industries have different interests. Many of the activities done by the forestry influences the reindeer husbandry in an undesirable way, simultaneously as the reindeer husbandry activities can have negative consequences for the forestry. One such forestry activity is fertilization.
It was during the 1960´s forest fertilization began to be practiced and the reason was that the increase in growth that the fertilization gave could be able to cover for the future shortage in wood many feared.
During the 1970´s when the fertilizing activities were most intensive about 200 000 ha was fertilized annually.
Minskad trädtillväxt under Lilla sitiden? : En dendroklimatologisk jämförelse mellan nutid och 1600-talet invid trädgränsen i norra Skandinavien
During the period called Little Ice Age (1400 ~ 1900) the climate of northern Europe was in an annual year-basis overall colder than it was before and after that period. The numbers of short, cold and rainy summers and long, bitter-cold winters where often repetitive under the approximately 500-years the period lasted. In Scandinavia, the coldest time during this period is estimated to have started around the end of the 16th century and lasted to the beginning of the 18th century. Trees growing at the tree-line are limited by temperature for their annual growth and hence showing differences of growth during changes in the climate, a method called dendroclimatology. The variations of growth can be read in the tree-rings either by analyze the width of the ring or by look into the density of the wood and is used to reconstruct past climates.
Effektivisering : En utredning om åtgärder på en industrifastighet
AbstractDelta Terminal owns an outdated industrial building which they now rent out to businesses. This property currently has a high energy con-sumption and therfore it is desirable to improve the efficiency. In ordet to reduce the energy consumption within the industrial building enve-lope, the heating systems and lighting are being investegated. A good building envelope emits less heat and thus reduces the energy consump-tion. An energy audit is a tool used to determine the energy loss.
Flerskiktat papper : en sammanställning av historia, teknik och forskningsresultat
Until the beginning of the 1900:th century the paper making process was handicraft. The paper machines that have been developed since then are as impressing in size as fascinating when it comes to the technique. The process has always been improved to give a better paper for lower costs, with as short manufacture time as possible. Stratified forming has been a reality since 1830. From the beginning it was applied to board and paperboard.
Lönsam energieffektivisering : Ett samarbete mellan ÅF och kund
This thesis project has focused on studying ÅF?s business concept Energy Collaboration, which is their way of selling energy efficiency services. Thereforeongoing projects have been analyzed. The purpose was to determine achieved energy efficiency, costs and profitability for the studied projects. It was concluded that the Energy Collaboration is a good way of selling energy efficiency services, since the customer takes no risk and energy savings of about 15-25 % can be achieved with simple measures.
Energy analysis of a fruit drying plant in Adeiso, Ghana
The purpose of the project has been to work out recommendations that reduce the energy-related costs and environmental impact of HPW Fresh & Dry Ltd., a fruit
drying factory in Ghana. The factory produces electricity with diesel and biogas but also purchases electricity from the national electricity company. Heat for the drying
process is produced from biogas, kerosene and solar panels. In the project the energy system was analyzed by measuring production and consumption of heat and electricity.
The project results show that the factory can become self-sufficient on heat if the available energy is used more efficient. The production units for both electricity and heat have low efficiencies.
Fuktproblematik i platta på mark : En analys av uppkomsten till fuktproblem
When constructing a building, a number of aspects must be harmonized in order for it to fulfill requirements ? a building must fulfill requirements such a load-bearing, conservation of energy and a good indoor environment by means of, among other things, moisture proofing .Moisture problems in buildings can affect health negatively. As we are increasingly staying in indoors, demands on a good indoor environment are higher.This work starts with examining moisture problems in slab-on-ground solutions, and then links the various scenarios to moisture problems in a concrete slab of a real building. The building with moisture problems is located in Årby by in Borlänge and moisture damage was found in the slab at an apartment adjoining wall.By reviewing literature written within the field of moisture problem, making hand calculations and modeling in the program Comsol Multiphysics, judgments are made to find explanations as to why the rise of moisture occurred in the building in Årby by.Generally, the following guidelines may be used to reduce the risk of moisture problems in slab-on-ground constructions:Drying of construction moisture before laying the floor material.Using draining layer beneath the slab, to prevent capillary suction.Using insulation under the slab, partly for comfort and to establish the temperature difference between the ground and the concrete slab.Avoid direct contact between the wood and concrete, due to degradation and fouling smells that normally occurs.If necessary, use additional vapor barrier.In addition to the above, there are various methods for moisture-proof and moisture-monitoring by design or by the method ByggaF suited for the entire construction process various events..