The purpose of this thesis for Sapa Heat Transfer is to examine a furnace in which aluminium is pre-heated before hot rolling. The project is modeled in a computer environment in which the air flow in the furnace and the heat transfer to the aluminium solids are included. The computer environment and its governing equations, as well as boundary conditions and generalizations, are presented and explained.The simulations are based on two models. The first model has an asymmetric solid placement, which is how it looks in today's ovens. It is validated against collected data.

Kompaktaggregat är ett integrerat FTX- och FVP-system som används i passivhus. Vi har gjortenergiberäkningar i programmet VIP+ för att se hur kompaktaggregatet skulle kunna fungera ipassivhus i Sverige.De resultat vi har fått fram ur VIP+ visar att passivhus med ett installerat kompaktaggregat klararav att nå passivhuskraven ända upp till Skellefteå. De beräknade värdena understiger kraven förpassivhus, men en viss marginal behövs för att kraven ska nås även efter uppförandet avbyggnaden. Vi har även tolkat tekniska uppgifter på ett sätt som enligt oss har en positiv effektför passivhus på kallare orter. Därför tror vi inte att värdena för de tre nordligaste platserna ärhelt tillförlitliga.

This paper goes through solar energy and what uses it has. It is also a guide in the choice of solar collectors forthe real estate that I have drawn for the thesis work.Solar energy is a renewable source of energy from the Sun's light. Energy can be used to produce both heat andelectricity through solar collectors and solar cells. Some of the benefits of solar energy is that it is completely freeto extract, environmentally friendly and virtually maintenance-free. Disadvantages are that the technology isexpensive, does not cover the entire energy needs and takes a long time until it pays.

Surveys show that consumers tend to avoid traditional marketing channels, leading the practitioners to use earned media channels through public relations (PR). This has also led to the use of covert PR. To understand the use of this communications method, the purpose of this thesis is to study campaigns, which have gained transmission in social media, by investigating how practitioners of three different campaigns motivate the choice to use covert PR.The study is based on a hermeneutic methodology and has an abductive approach. It is carried out by semi-structured elite interviews with six contributors of three different campaigns, using covert PR. The primary data consists of the empery of the interviews, while the secondary data consists of a theoretical framework of excellence in public relations, the PR practice and viral messages.The result of the study indicates the point of view that covert PR has given the campaigns a wider reach.

Storage of biomass is often associated with problems such as heat development, dry matter losses and reduction of fuel quality. The rise in temperature can potentially cause a risk of self-ignition in the fuel storage. Moreover, emissions from storage piles can cause health problems in the surrounding. The dry matter losses and reduction of fuel quality can have economical effects. The aim of this thesis project is to develop guidelines on how to store large amount of biomass at Vattenfalls heat and power plants in an optimal way.

This thesis calculates and compares the values of improved environmental quality due to future possible investment alternatives in biogas production facilities at Käppalaförbundets Reningsverk (Käppala Sewage Treatment Works) in an attempt to determine which alternative yields the highest such value. Käppala faces three investment alternatives for the usage of biogas. The alternatives are production of vehicle fuel, district heating and thirdly, heat and power production. Estimates of the value of environmental change are calculated for each of the three investment alternatives, and these estimates are then compared. The environmental change in question is the change in discharge levels of carbon dioxide (CO2), nitrogen oxides (NOx), sulphur dioxide (SO2) and particle matter.

A new build in the Swedish nuclear power system would entail increased re-quirements for the proposed repository, which is adapted after the reactors of today. With a fast reactor, capable of burning nuclear waste, operating in parallel with the light water reactors, the increased requirements on the repository could be reduced.In this thesis, simulations of a light water reactor and a fast reactor have been performed by using the Monte Carlo code Serpent to investigate the changes in the fuel inventory. The light water reactor in the study is a boiling water reactor and the fast reactor of the type sodium-cooled fast reactor and they have been used for three different operation scenarios.By studying the fuel composition and the results from the simulations of the three scenarios conclusions can be drawn. Conclusions regarding the change of the fuel inventory and decay heat in Clab as well as the interim storage facility and in the repository. Depending on the operation alternative the changes dif-fered significantly and especially regarding the mass of burned actinides for different fuels in the fast reactor.The lowest increase of fuel assemblies was meet when using 50 years old fuel with 20MWd/kg U burnout and 2,0 % enrichment for start up of the fast reactor and 30 years old fuel assemblies with 50MWd/kg U burnout and 4,7 % enrichment for the further operation of the reactor.The increase of the number of fuel assemblies was 3174, which is equivalent to 641tons of heavy metal.

The number of data centers and their capacity is increasing throughout the world. Theenergy used in these data centers and the emissions from the use are increasing at thesame rate. The total use of energy will double from 2008 to 2011 based on the trends indata centers use. Research in this area says that the emissions from data centers willhave surpassed the level of airline traffic in 2020. The index used today to compare howefficient a data center is, called PUE, is lacking some information.

Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.

Antalet järnvägstunnlar i tätbebyggda områden kommer att öka de närmaste 20 åren. Därför finns behov av bra förutsägelser om vibrationer och ljud orsakade av tåg i fastigheter utmed de planerade tunnelsträckningarna. Förståelsen för hur tåginducerade vibrationer propagerar i bergmassan är i dagsläget begränsad. Eventuella för- och nackdelar med bergets och sprickors egenskaper kan då inte utnyttjas optimalt. Syftet med detta examensarbete är att studera hur lågfrekventa vågor propagerar genom (i) en godtyckligt orienterad spricka samt (ii) multipla parallella sprickor.

A zoonosis is a disease or infection that is naturally transmitted between vertebrate animals and humans. The majority of infectious diseases that affect humans are zoonoses. Environments where wild animals, domestic animals and humans live in close proximity with no or small boundaries in the ecological system favor the transmission of diseases between animals and humans. The above described situation is more common in low income countries, where humans and animals live in high density and zoonoses are generally more common. The study was conducted in Cambodia.

Gunsta is situated about 10 km east of Uppsala. Today there are plans to establish 1000 new households in Gunsta before year 2030. The required energy for heating houses and water would be distributed via a district heating system, which also includes 200 existing residences. The annual required energy, according to this study, would be 16.2 GWh with a maximal peak effect of 6.9 MW. To meet this need, the study suggests a system with heat pumps to upgrade the 31?C water from a 1.8 kilometre deep borehole.

The price of farmland has risen sharply in the last 20 years. This has led to discussions about what creates the value of farmland. The aim in this study was to try and find what factors are affecting the price on farmland. The area that is studied is the counties around Mälardalen during the period 2005 to 2009.The method chosen to achieve the objective is the hedonic price model. The variables are chosen after a preliminary study where a literature search has been made and a number of interviews with people in the industry.

Floor surface in pig facilities can have an impact on animal welfare and pig health, as it can cause the pig physical damage and thereby increased risk of infectious diseases and lameness. The development of pig housing systems has resulted in a decreased use of bedding. It seems hard to find the optimal floor in farrowing pens, as it must suit both the sow and piglets. The floor friction needs to be adequate to avoid slips and at the same time should the floor be non-abrasive. Abrasions and lesions caused by the floor are not only causing the animal suffering, but are also negative from an economical aspect.

A problem in the field of district heating is the oil burners needed to provide power when a peak load occurs. One possible way of reducing the needed amount of oil is to reduce the power demand for space heating in the district-heating substations when the need for district heating water exceeds a certain limit. This can be done by use of a locally working controller function.In this Thesis the options concerning load priority are evaluated. To evaluate the potential for using controller functions concerning peak load priority an experiment was brought out in a chosen district-heating substation. The impact on the indoor thermal comfort during a heat reduction was also taken into account.