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1720 Uppsatser om Heat treated wood - Sida 20 av 115

Deadwood in piles or distributed : does it make any difference to saproxylic beetles?

Piles of deadwood are often retained in forests after management to support the biodiversity ofsaproxylic organisms which depend on deadwood to survive. Any knowledge about the crucial role ofpiles as suitable habitat of saproxylic organisms compared to single distributed deadwood objects thatare around the piles would help conservation actors to motivate more forest owners to supportsaproxylic organisms during their management. Therefore to give facts to this the saproxylic fauna ofdifferent pile positions (up and low) was studied and compared to distributed deadwood samplesaround each pile. Our study was focused on saproxylic beetles. Some other parameters such asdiameter, deadwood volume, pile volume and decay stage were assessed to define any effect.

Framtidens Hus

The company Sol & Energiteknik wanted to examine the possibility to make a standardhouse totally energy independent. Based upon this I have, during the spring of 2007,examined the possibilities available at the market today through litterature studies, contactwith several companies and reading reports at the internet.The first thing to examine has been to determine the energy consumption for a standardhouse, and find out if there are better technologies to be used for energy conservation.My conclusion in this matter is that there are possibilities today for building a house moreenergy efficient.When I had reached the point at which my design for the house was decided, I also hadto choose the different products to use to produce energy as well as to store that energy.To produce heat and electricity to the house I decided to use a wind turbine and a solarwater heater.The most difficult part of designing a house that is energy independent is that theproduced energy must be stored somehow. Storing the heat is relatively easy beacuse theheat can be stored in a large water tank. The electricity is a bigger problem beacuse itmust be stored in batteries, which today are too expensive to be used in a standard house.In the future producing and storing hydrogen might be used to produce electricity, buttoday that technology is both expensive and not tested enough.My final conclusion is that a standard house can not be built to be totally energyindependent today, unless it is very expensive to connect the house to the electricitynetwork. As an alternative solution I came up with a proposal for a house which isconnected to the electricity network and have some amount of own produced energy.This house prooved to be a good investment if you choose to build it today, and it couldbe a very good investment in the long run beacuse energy prices increase every year..

Större svartbagge Upis ceramboides i norra Hälsingland : förekomst, substratkrav och effekter av skogsbrukets naturvårdsåtgärder

Many wood living insects are considered threatened by modern forestry due to the reduction in amount of dead wood. During the last decade various methods have been used to enhance the quantity of dead wood in managed forests. However little is known how and if these methods are aiding saproxylic insects. The threatened tenebrionid beetle, Upis ceramboides, is already extinct in southern Sweden. It develops in white rotted dead birch (Betula spp) and requires sun-exposed sites.

Uppvärmning av mjölkgård med ved, flis eller havre :

The background for my thesis is the fact that with rising electricity and oil prices it becomes interesting to calculate on alternative heating systems. I have chosen to calculate upon my parents? farm, which today heats the dwelling house with wood. This is very time-consuming work, time which could be spent on other work. The main objective for this study is to compare three different heating systems to decide how they differ considering effort and cost. The result from the calculations was that grain-heating system demanded the least amount of work, but the total cost was a little higher compared to chips heating. Chips heating required half as much work as today?s wood heating and had a little lower total costs compared with the corn heating. Which system to choose largely depends on how the own work is valued.

Energianalys av hygieniseringssystem : jämförelse av befintlig pastörisering med integrerad termofil hygienisering på Kungsängens gårds biogasanläggning i Uppsala

The biogas plant Kungsängens gård, owned by Uppsala Vatten och Avfall AB, produces biogas and biomanure from organic household waste, food processing waste and slaughterhouse waste. In year 2012, 4.4 million Nm3 of biogas were produced from 25 200 tons of waste. Before digestion all substrate is sanitized by pasteurization at 70°C in order to kill pathogens. Another method, integrated thermophilic sanitation (ITS), is of interest in order to decrease the energy demand. The method implies that the substrate is sanitized during ten hours in the digestion chamber, where the temperature is 52°C.

L?ggning av ett kils?gat br?dgolv

This bachelor thesis contains the findings of an investigation into the laying of wedge sawn wood flooring. The advantage of wedge sawn wood flooring is the usage of more material from each board reducing waste. The boards follow the natural profile of the tree where the root part of the board is wider, and the top part is narrower. The technique involves placing boards side by side with adjacent boards in opposite directions. The thick base of one board is neighbored by the narrow top of another, this creates a pattern of wedges in alternating directions, known as a ?root and top? system. Existing literature into this type of flooring is sparce.

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.

Energieffektivisering i ett verkstadsföretag : En analys av energibesparande åtgärder samt uppvärmnings- och kylsystems driftkostnader och koldioxidutsläpp

The energy use in a workshop company has been examined in this work in order to find areas for energy efficiency improvement. The combined oil and electricity heating in the company were compared with other alternative heating systems including cooling of the premises in following combinations:Ground source heat pump for heating and coolingDistrict heating and absorption coolingDistrict heating and low temperate surface water coolingEnergy use, operation costs and carbon dioxide emissions were calculated for the current heating systems and the three alternatives including cooling. The ground source heat pump for heating and cooling decreases bought energy with 34 MWh annually compared to current heating only. The district heating and low temperate surface water cooling has the largest reduction of operation cost and carbon dioxide. The operation cost decreases with 42 kSEK and the carbon dioxide with 43 metric ton CO2 annually.

Energianvändning för markkonstruktioner förlagda med ytvärme : En teknisk och ekonomisk utredning av fördelarna med att isolera under värmerören

The need for snow-free surfaces at squares, bus stops, platforms, car parks and sports facilities increases and at the same time energy price rise and the environment is becoming a hotter issue. The construction of the ground heating systems often lack thermal insulation under the heating pipes, which means that the heat from the pipes not only warm up the soil surface but also heats the surrounding soil. The insulation also has more features, by insulating the risk of frost damage is minimized. The goal of this report is to demonstrate the large heat loss and energy costs in the absence of insulation under the heating system.The report begins with a scientific way to study and treating the soil heating system uses, and the theory involved. Furthermore it also deals with different routing principles of heat pipes depending on the facility.All calculations are made with so called finite element method (FEM), in COMSOL Multiphysics 3,5a, where models are created with different conditions.

Föränderlig sittmöbel - att trolla fram en extra plats

The purpose of my project was to explore variability. I wanted to combine different ways of sitting and create some kind of seating furniture that could be changed to fit different kinds of situations and needs. I sought after a way to express safety and stability in the seating furniture and at the same time make it clear that it could be changed into something else or something more. It was very important to me that the furniture piece would have a long lifetime and would be something you kept for a long period of time. I decided that the changeable factor in my piece would be the possibility to change it from being a chair for one person into being a bench for two people.

Död ved i vatten - funktionella strukturer och dess påverkan på öring (Salmo trutta, L.)

The background to this work was to see if there was a connection between large woody debris (LWD) and the presence of brown trout in our Swedish forest streams. Previous researches by Degerman et al. (2004) have shown that there is a strong correlation between the amount of dead wood and the presence of brown trout. The goal was then to find a way to restore, maintain and increase the trout habitats by constructing and adding manmade wooden structures that would mimic natural deadwood and its features in flowing water. The inspiration was partially taken from a water restoration program in the Klamath River of northern California, USA.

Passivhus, detaljutformning och dess köldbryggor

Along with rising energy prices and increasing awareness of environmental issues, the criteria for buildings energy performance have been sharpened through the years. Today, ?passive house? and ?low energy house? are commonly used phrases in the construction industry and is expected to become increasingly common in the future.For houses with well-insulated building envelope the importance of well constructed details increases when minimizing the heat losses. Examples of these details are floor-wall junction and window openings in the wall. In such connections thermal bridges occur, which means that heat more easily is transported out of the building, compared to the rest of the building envelope.This report deals with detail solutions around windows and a comparison between a traditional slab and a foundation from Koljern consisting of foam glass.

Energianalys av hygieniseringssystem : jämförelse av befintlig pastörisering med integrerad termofil hygienisering på Kungsängens gårds biogasanläggning i Uppsala

The biogas plant Kungsängens gård, owned by Uppsala Vatten och Avfall AB, produces biogas and biomanure from organic household waste, food processing waste and slaughterhouse waste. In year 2012, 4.4 million Nm3 of biogas were produced from 25 200 tons of waste. Before digestion all substrate is sanitized by one hour?s pasteurization at 70°C in order to kill pathogens. Another method, integrated thermophilic sanitation (ITS), is of interest in order to decrease the energy demand.

Effects of shade on milk production in Swedish dairy cows on pasture

Heat stress negatively influences the performance of dairy cattle such as lactation and reproduction. Heat stress can cause production losses as well as welfare problems. Years of research have shown that heat stress is a huge problem for dairy cattle in both the tropics and temperate zones but no such research have so far been done in northern European countries. It seems like shade is an important tool when improving pasture conditions and therefore deserves more attention. The aim with this study was to investigate whether there is a need of providing shade for grazing dairy cows during the summer in Sweden. Two groups of lactating Swedish Red dairy cows (n=15 per group) were kept on pasture.

Studie av Karlskogas fjärrvärmenät för att sänka returtemperaturen

A district heating plant has the advantage that it can take advantage of the waste heat from industries and use of cheap fuels to produce heat. But for the long term is competitive requires that energy is also saved in district heating plants. One way to save energy in a district heating system is to increasing cooling to the return temperature. This leads to less power needed to drive the distribution pumps,  and that more energy could be extracted from the same amount of fuel by an improved flue gas condensation.In Karlskoga the return temperature into the district heating plant is high. They would therefore reduce the return temperature in order to extract more energy from the flue gases.

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