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1564 Uppsatser om Heating water - Sida 58 av 105
Grön asfalt och NCC : rätt tillväxtstrategi för en asfaltproducent?
NCC ROADS Sweden east is a part of the NCC Corporation. The company mainly
produces aggregates, asphalt and concrete. They have taken the environmental issues
seriously and been working with that since the middle of the nineties. When
manufacturing asphalt large a quantity of fossil energy is needed. The company is now
about to make further progresses by manufacturing environmental friendly asphalt
(?green asphalt?) with using bio-energy.
Deaktivering av metanisering katalysatorer
A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and compare it with an alumina-supported nickel catalyst.The titania-supported catalyst did not only show higher stability than alumina, but also presented a different cause of deactivation, carbon formation. In addition, a kinetic model was obtained for the titania-supported catalyst, and a study of the effect of different operating conditions (temperature, composition and partial pressures of synthesis gas and water) on the deactivation rate and carbon formation of this catalyst was performed.
Val av överlastskydd för elektriska ventilmanöverdon på kärnkraftverket i Forsmark
At nuclear power plants, electrical valve actuators are important for ensuring that the reactor core is water covered and the pressure in the reactor tank and containment is limited. The electrical actuators are provided with overload protection in case of drawing higher current then the motors are rated for. When safety manoeuvres are needed, the overload protection must not trig and cause the valve to stop before completing the manoeuvre. Analyses have showed that the current settings of the overload protection may cause an illegitimate trig at the worst theoretically possible accident. A new method has been developed with conservative assumptions and applies overload protections for all electrical valve actuators at the three reactors in Forsmark..
Effekt av biotopvård på öringpopulationen i två vattendrag
I have done a follow up study of the restoration of two rivers, Röälven and Grundan, in order to evaluate the effects of the restoration on the endemic population of trout. Both rivers have been used for timber floating during many years throughout the 20th century, and because of this, had all obstacles such as rocks and wood parts removed. In 2004-2005 both rivers were restored, and rocks and wood were put back into the rivers. Spawning grounds were created and boulder dams were constructed to promote the streaming water. The result showed that the trout population of both rivers increased after the restoration, but also that the trout population of Röälven increased more than that of Grundan.
Sådd av tallfrön med vattenryggsäck : en laboratoriestudie
Föryngring av skog är en nödvändig, men kostsam åtgärd och därför är det eftersträvansvärt att hitta en föryngringsmetod som är både kostnadseffektiv och ger en bra föryngring. Ett sätt att få en billigare föryngringsåtgärd är att använda frösådd. Vid en lyckad sådd gör det stora plantuppslaget att plantorna får bra förutsättningar för god kvalitet. Dessa plantor får dessutom bättre rotutveckling och stabilitet än planterade plantor. Användningen av skogssådd är dock begränsad av bl.a.
Flygplansavisningens miljöpåverkan vid svenska flygplatser
The aim of this thesis was to answer a number of questions about the environmental consequences of aircraft de-icing. A further aim was to suggest how the environmental consequences due to the release of de-icing fluids can be measured and reduced.The main impact of the aircraft de-icing on the environment is due to the large oxygen demand for the degradation of glycol based de-icing fluids which are released in the environment. The effect of the increase in oxygen demand depends on where the degradation occurs in the ecosystem. In a sensitive ecosystem, the large demand of oxygen could provide an anaerobic environment which would be harmful for many types of organisms.In order to reduce the negative effects of the applied de-icing fluid, there is some type of collection system at every regular airport in Sweden. The methods of collection can be divided into two general groups, hydrological isolation or vacuum sweeper trucks.
Hydrauliken i Ångersjöns fosforfällor : bestämning av flödesvägar och åtgärdsförslag för optimal fosforbindning vid avloppsrening med reaktiva filter
Discharge of untreated wastewater leads to unnaturally high levels of nitrogen and
phosphorus in rivers, lakes and the sea, which results in unbalanced ecosystems with
eutrophication and lack of oxygen. Part of the phosphorus in surface waters is coming from
on-site wastewater treatment from scattered households with unsatisfactory purification.
Blast furnace slag is a by-product from iron production, and has in laboratory trials showed good phosphorus binding capacity. To test blast furnace slag as a reactive filter media for phosphorus separation in a full scale experiment, a wastewater treatment plant has been built behind the picnic area at Ångersjön alongside the road E4 in central-eastern Sweden. The plant contains two parallel lines, one with blast furnaces slag and the other with Filtralite-P as phosphorus sorbent. Both filters have showed decreasing phosphorus purification effect with time in spite of a low wastewater load.
Solceller ? Solen är ju gratis! : En undersökning av huruvida solceller är ett fördelaktigt energisystem med avseende på tekniska och ekonomiska aspekter
This report is a result of a bachelor thesis at the school of Architecture and the Built environment (corresponding to 15 HP) and is written during spring 2012 at the Royal Institute of Technology (KTH) in Stockholm. The Bachelor's essay is based on the design and dimensioning of a house which is located at a predetermined site in Malmo, Sweden.The idea is to construct a house that is appropriate to use for an average Swedish family of four family members. The house is designed in a modern way with respect to ease of access and disabled facilities. The installation that have been considered are heating, ventilation, sanitation and electricity. Construction calculations and material selection are also discussed.Furthermore, a study about photovoltaic cells has been done.
Smärtlindring i samband med vaccination av fisk :
Vaccination of fish can be assumed to cause pain. This study was designed to see if we can minimize the suffering of fish following vaccination.
Fishes are cold-blooded animals and thus more primitive than warm-blooded animals. Despite this, many organs, e.g. the nervous system, have the same basic structure as that of other vertebrates. The fibre system for conducting pain is more diffuse than in humans.
Underlag för bedömning av energibrunnar inom vattenskyddsområde
Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.
Kan en standard för miljökommunikation förbättra miljöprestanda? : Ett examensarbete i samarbete med NQA Nordic AB
Mankind has always been communicating, it is almost impossible to not communicate. The communication tree has grown a new branch, the environmental communication branch, and an ISO standard, the ISO 14 063 Environmental communication- guidelines and examples was issued October 2006. The purpose of this thesis is commissioned by the managing director of NQA Nordic AB in order to examine and analyse how organisations communicate environmental issues today, and how big the need for ISO 14 063 actually is, and further more if there are needs and wishes to make ISO 14 063 a certifiable standard. The main conclusion is that the there is a need for the standard, but it is difficult to say in which form since the knowledge about the standard is far to low among the organisations examined in this thesis. Clarity and transparency as ISO 14 063 promotes are important ingredients in organisations? environmental work, so sure a standard for environmental communication can help improve environmental performance, for example through opening up for two-way communication and from that on take part of the stakeholders? opinions.This study is based on a literature study and a questionnaire survey where 70 organisations (in this case authorities, corporations and non-governmental organisations) randomly chosen from the seven criteria, which ISO 14 001 defines as the environment: land, water, air, flora, fauna, natural resources and man and his collaboration with those.
Är det möjligt att använda SCR-rening av rökgaserna vid inblandning av avfall i biobränslet?
Waste appears to be a low-cost fuel compared to biofuel. This Masters thesis was conducted for Vattenfall Utveckling AB and deals with how waste in the fuel affects the performance of a SCR-catalyst. Different mechanisms of deactivation were surveyed, focusing on the poisoning mechanism. A literature study was carried out, which was used as a reference when analysing the results.Small samples (9x2x2 cm, 64 pieces) cut out from a full-scale unused honeycomb catalyst were exposed up to 1500h in two different combustion plants, Johannes in Gävle (co-combustion) and Högdalen in Stockholm (waste-combustion). The activity was measured mainly at 300°C but also at 250, 350, 375 and 400°C.
Brännskuggat fanér - en metodanalys
This thesis is about a part of the marquetrytechnique, scorching. Scorching is made by heating up something, put a veneer into the heated substance and make a controlled burning. This technique is old but still used today and have according to me great potential for development. In my work I wanted to give the scorching greater room then I earlier have seen. I wanted the scorching to be the dominant ingredient for a decorative element in a piece of furniture or an interior.
Två metoder av finutsättning och dess noggrannheter
This report describes a study of two different methods to achive the best possible result in setting out apartment details. These two methods are the setting out of details with a measuring tape from baselines and the setting out procedure with an instrument (totalstation).Through our knowledge in surveying and mapping technology and help from a carpenter, this investigation has been implemented. The setting out using a tape has been performed by letting the carpenter to set out windows, bathroom and water- and drain-details from baselines and drawing. The setting out using a surveying instrument was carried out by means of a Trimble Total Station. These two methods have been compared in order to detect and show the difference that occurs.The report shows the investigation background story from the practice of Swedish Mätcenter in Karlstad.A result of differences in accuracy and time is described in the report, as well as their theoretical consequences.
Föroreningstransport med dagvatten - Utveckling av reningsmoduler för modellverktyget Mike Urban SWQ (Storm Water Quality)
On a request from the water sewage plant Gryaab in Gothenburg a power quality survey was performed. The voltages and currents have continuously been sampled in the incoming 10 kV substation HSP01 from April-August 2008. Power quality measurements were also performed in Gryaabs other 10 kV substation HSP04 fed from HSP01 and at the terminals of the induction motor IN_PU4040 of 1.3 MW which controls one of the four large inflow pumps to the plant. The reason for the latter measurement was due to registered negative transients each time the motor was connected to the grid. The cause of the transients could be explained by the coupling in the substation, the ageing of the motor which could result in damage of the bearings or resonance in the motor circuit which amplifies high frequency harmonics.