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851 Uppsatser om Heat recovery - Sida 15 av 57
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.
Utsikten : Hållbara uppvärmningsalternativ för vandrarhemmet på Finnhamn
Finnhamn is a small group of islands in the Stockholm archipelago. At Stora Jolpan, the biggest island, there is a hostel. The main building was built in 1915 and is called Utsikten. The purpose of this project is to on behalf of the Archipelago Foundation (Skärgårdsstiftelsen) find alternative systems that can replace the existing heating system of Utsikten (an oil-fired boiler and electricity heaters) to a system with renewable energy. The alternative system that this project focuses on is a system of solar collectors combined with a wood chip boiler.
Kriskommunikation : Hur företag med hjälp av en modell kan hålla huvudet kallt genom en kris för att bevara kundens varma attityd till deras varumärken
Syftet med undersökningen är att arbeta fram en modell för hur företag bör arbeta innan, under och efter en kris för att bevara sitt varumärke. Studien baseras på en kvalitativ undersökning där primärdata insamlats via intervjuer med sex experter inom området kriskommunikation. Ett abduktivt tillvägagångssätt har används då fokus växlat mellan empiri och teori, men där största fokus legat på empirin. Teorin har insamlats via litteraturstudie där vetenskapliga artiklar hämtats från olika databaser, såsom google scholar och ABI/inform. Slutsatsen genererar i ett verktyg i form av en modell som ger riktlinjer på hur företag kan arbeta innan en kris för att förebygga och förbereda. Den visar även på hur företag arbetar under en kris för att minimera skadan av den samt hur de på bästa sätt kan återhämta sig från den.
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.
Klagomålshantering inom hotell : En kvalitativ studie om klagomålshantering och samspelet mellan managers och frontpersonal
Konkurrensen mellan hotellen idag ökar kraftigt. Hotellen måste fokusera på att verkligen göra gästerna nöjda för att de ska kunna konkurrera på marknaden. Oavsett hur bra service hotellen har så har det visat sig att misstag i servicen är oundvikliga, vilket ställer höga krav på hotellen att reparera sig från dessa misstag. För att hålla gäster nöjda krävs en god "service recovery", att vända missnöjda gäster till att bli nöjda. Receptionisterna är de personer som möter flest klagomål eftersom de interagerar med gästerna kontinuerligt.
Fluidrörelse- och värmetransportsmodellering i götugn
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.
Småhusutformning och solenergiutnyttjande
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.
Energy efficient storage of biomass at Vattenfall heat and power plants
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.
Biogasanvändning vid Käppalaförbundets Reningsverk: ? en värdering av miljöeffekter
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.
Uppmuntra till att klaga : En kvalitativ studie om hur B2B-företag uppmuntrar till klagomål
Många service-företag börjar att i, allt högre grad, mäta kundlojalitet som ett mått på lönsamhet. Samtidigt kommer rapporter om att kundnöjdheten minskar inom många branscher. Ett sätt att öka kundernas lojalitet är genom service recovery, då företag aktivt jobbar med att ta emot och hitta klagomål för att kunna åtgärda dem. Detta eftersom att de på så sätt kan omvända missnöjda kunder till lojala sådana. För att kunna utföra service recovery måste dock klagomålen först och främst komma företagen till känna, vilket har visat sig vara ett problem.
Tidig postoperativ övervakning av smådjur : förekomst av standardiserade rutiner
Background. Anesthetic-related death in small animal anesthesia is about ten times more common than in human anesthesia. Recent research identifies the early postoperative period as particularly risky and highlights the need for regular and careful monitoring of the veterinary patient during this period.
Objective. The aims of this study were to investigate whether there are standard procedures in terms of regulated routine patient observations and record-keeping during the early postoperative period at Swedish veterinary clinics, and if there are any guidelines for monitoring the veterinary patient during recovery.
Methods. A small survey including ten Swedish veterinary clinics was carried out as well as a literature review.
Results.
Förutsättningarna för ett parallellt generation IV system vid svensk nybyggnation av kärnkraft.
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.
Energieffektivitet i datahallar
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.
Geotermisk fjärrvärme i Gunsta
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.