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295 Uppsatser om Nitrogen retention - Sida 14 av 20

Biologiska behandlingsmetoder för rening av rejektvatten från biogasproduktion

In this literature review the characteristics of two free-floating macrophytes, water hyacinth   (Eichhornia crassipes) and duckweed (Lemna sp.), and two microalgae, Chlorella and Scenedesmus, have been examined regarding their suitability as efficient nutrient removers in the treatment of wastewater with high levels of nutrients and suspended solids from a biogas plant in Loudden. The needs required for the plants to be able to grow in wastewater and the amounts of biomass they can produce have also been studied. The results show that Chlorella is capable of a very high uptake of nutrients in photobioreactors with high nutrient loadings. With an ammonia uptake maximum value at 10900mg/m2/d Chlorella outshines the other organisms in this study. The test organism that performed the closest to Chlorella in terms of nitrogen uptake was water hyacinth with an uptake about 1602mg/m2/d.

Miljöarbete inom den civila luftfarten

The main environmental problem for aviation is the great amount of exhaust gases, mainly nitrogen oxides, carbon monoxide, carbon dioxide and hydrocarbons - mostly "greenhouse gases" leading to climate changes. I decided to sort out what is being done to decrease these problems and what regulations there are concerning air pollution by the means of searching the internet and using publications from aviation authorities for current figures. I chose to scrutinize authorities on political, authority and company level, resulting in summarizing the work of UN and EU respectively, ICAO (International Civil Aviation Organization), JAA (Joint Aviation Authorities) and LFV (Swedish Civil Aviation Authority), and finally SAS, representing the airline companies. Conclusion that I have drawn are thatthere are regulations for air pollution, written down in ICAO's Annex 16, that are to be followed. Secondly, LFV are environmentally controlling their nineteen airports and since economy is an important reason for not giving priority to environmental issues in aviation emission charge and noise charge are added to the landing fees.

Ammoniakförluster vid flytgödselhantering : myllning och surgörning som metoder för att minska avgång vid spridning

The ammonia emissions are an environmental issue since they contribute to eutrophication. By far the largest source of ammonia emissions is manure from agriculture and should therefore be reduced. Loss of ammonia is not only negative for the environment but also to the farmer who loses nitrogen that could have been used by the crop. The focus of this study has been emissions from spreading slurry where the loss can vary widely depending on slurry-, soil-, and weather conditions. There are mainly two different ways to reduce the emissions. One is to inject or mix the slurry into the ground to avoid air contact. The other way is to use acid to reduce the pH in the slurry to a level between 5 and 6 where the equilibrium is so strongly pushed to NH4+ that hardly any NH3 can be lost.

Rening av avloppsvatten med anaerob membranbioreaktor och omvänd osmos

This master's theses was carried out on assignment from Stockholm Vatten AB as a part of a project developing new waste water treatment techniques. The goal of the theisis has been to evaluate an anaerobic membrane bioreactor for treatment of waste water from Hammarby Sjöstad. The bioreactor has not been heated and the main interest has been to study the gas production, power consumption and the reduction of organic matter and nutrients.The system has been completed with a reverse osmosis unit and a total of four batch runs have been made with good results. The use of reverse osmosis allows nutrient in the waste water to be reintroduced into circulation as the reverse osmosis concentrate can be used as crop nutrient.The membrane unit is of VSEP ("Vibratory Shear Enhanced Processing") type and an extensive membrane test has been conducted. This so called L-test helped determine the most suitable type of membrane for the system to allow a higher ±ux and thus lower power consumption.

"Ska jag ta de här tabletterna?" : Behandling med statiner från kranskärlspatientens synvinkel, en kvalitativ intervjustudie

Background: Coronary heart disease kills more than 7 million people worldwide each year. High levels of blood fat, cholesterol, contributes significantly to coronary heart disease. Lifestyle changes combined with lipid-lowering drugs, statins, is an effective treatment. But adherence to statins is low, not even a myocardial infarction always contributes to adherence. Adherence requires patient education and good communication between patient and physician.

Bakterietillväxt i strömedel till mjölkkor

The resting area is the most important place in the barn for the dairy cow, sometimes called the heart of the free stall system. Inadequate design of the lying area, and lack of or poor quality of bedding materials may reduce the hygiene of the stall. Poor management regarding the cleanliness of the resting area may lead to poor animal hygiene and increased bacterial growth. This in turn will lead to increased risk for environmental mastitis as well as impairing milk quality through contamination with spores. In this literature study the most commonly used bedding materials; straw, sawdust, wood shavings, clean sand, recycled sand, peat and recycled manure solids, are compared to one another with regards to their ability to resist bacterial growth. Effects of adding hydrated lime to bedding materials have also been studied. Most bacteria need humidity and prefer a quite high water activity to be able to grow.

Utvärdering av ett Bränslecellsdrivet Flygplan.

 With the increases in fuel costs due to the depletion of the world oil reserves and the increase of greenhouse gasses as a consequence to using oil as a fuel many companies are looking to new and innovative ways to power their aircraft. One of these new ways to power an aircraft is using fuel cells powered using hydrogen and oxygen, thus producing nothing but water vapour and small amounts of nitrogen dioxide as well as trace amounts of other emissions. Both Boeing (1) and Politecnico di Torino (2) have shown that it is possible to build an all-electric aircraft powered by fuel cells. Both flights used small, two-seater aircraft and a constant between them was the loss of the co-pilot seat due to weight and lack of space. As this paper will deal with a commercial aircraft a primary concern is the cargo and passenger capacity and whatever impact switching propulsion system has on these.

Utvärdering av anaerob behandling av hushållsspillvatten och tekniker för efterbehandling

The continuous process of urbanization results in demands on research and development for ecological and sustainable city development. Because of this, the current systems for wastewater treatment may have to be improved. In order to evaluate new technologies for municipal wastewater treatment, a development project has been initiated for the new district Hammarby Sjöstad in Stockholm. The project is lead by the company Stockholm Water. High environmental standards have been put up for the district, as it must be twice as good as an ordinary new district.

Att arbeta till sjöss - Vad motiverar svenskar att välja och behålla sjömansyrket?

2008 kom den första rapporten från Shiptalks undersökning ?Life at Sea ? Seafarer Attraction and Retentention Survey?. I rapporten presenteras vad respondenterna i den internationella studien anser är det viktigaste respektive värsta med livet till sjöss, varför de en gång gick till sjöss och vad som får dem att stanna kvar (Shiptalk, 2008). Rapporten visar intressanta resultat och att göra en liknande undersökning med fokus på svenska sjömän föreföll vara en värdefull idé. Med hjälp av en internetbaserad enkät var det möjligt att erhålla svar från nästan hundra aktiva sjömän på vad som fick dem att gå till sjöss och vad som får dem att stanna kvar.

Fasadism som kulturv?rd

This study is an investigation of how fa?adism can be understood as an act of conservation and compensation in Sweden, through the definition of fa?adism as the act of retaining or reconstructing an existing fa?ade with the construction of a new building behind the fa?ade. The study is executed through an investigation and analysis of the definition of fa?adism, arguments for and against fa?adism related to authenticity, and through an analysis of how current legislation, policies and charters regarding conservation and/or compensation can support or counteract fa?adism. The first part of this study is executed through a literature study of fa?adism on an international level.

Hur kan kundrelationer upprätthållas?: när möjligheten
till fysisk kontakt gentemot kunden begränsas

Relationsmarknadsföring består av att antingen skapa, upprätthålla eller avsluta relationer gentemot företagets kunder. Betydelsen av att upprätthålla relationer med befintliga kunder har ökat under de senaste åren, mestadels på grund av en ökad global konkurrens. Frågan är då hur ett företag upprätthåller relationen med kunden, när det väljer eller tvingas avveckla en distributionskanal vilket begränsar möjligheten till fysisk närvaro gentemot kunden. Denna uppsats syftar därmed till att utreda hur ett företag kan bibehålla kundrelationen när den fysiska kontakten gentemot kunden begränsas. I syfte att undersöka detta utfördes två fallstudier på Scandinavian Airlines System, SAS och Zytt.

Effects of milking system on plasmin and plasminogen activity in bovine bulk milk

Protein is an important component in various milk products and has a crucial role in the final quality. Excluding non-protein nitrogen, bovine milk contains about 3.3% protein whereas about 80% of this fraction consists of casein. There are four major members in the casein family: ?s1-casein, ?s2- casein, ?-casein and ?-casein. Proteolytic enzymes are the cause of degradation of the economically important milk proteins.

En internationell jämförelse av miljölagstiftning avseende växtnäringsläckage med ursprung i jordbruket

SAMMANFATTNINGÖvergödning har de senaste åren blivit en stor och omdebatterad fråga i många EU- länder.Även om problemen har minskat en del är detta inte tillräckligt, vi ser fortfarande fiskdöd,syrefria bottnar och giftiga algblomningar. Hur långt ska vi gå för att kunna övervinnaövergödningsproblemen? Genom olika sorters lagstiftning, ekonomiska styrmedel ochrådgivning har vi nått en bit på vägen, men fortfarande krävs det mycket arbete innan vi haruppnått målet. Jordbruket har pekats ut som en av de största källorna till övergödning pågrund av överskottet av kväve och fosfor som varje år urlakas ur våra jordbruksmarker.Inom EU finns sedan 1991 en gemensam lagstiftning; Nitratdirektivet. Syftet med direktivetär att minska nitratföroreningar och andra föroreningar från jordbruket, då dessa påverkarsåväl yt- och grundvatten som kust- och havsvatten.

Kartläggning av flamskyddsmedel till polyester och polyamid

Flamskyddande kemikalier används idag inom en hel del olika områden. Ett stort område är textil, där hemtextil är dominerande. Det finns en mängd olika typer av flamskydd på marknaden. Alla har till uppgift att sakta ner brandförloppet eller helt förhindra att en brand uppstår. De halogenerade flamskydden är de mest effektiva men har många kopplingar till miljöproblem.

Kraven på ägare till minireningsverk skiljer sig åt mellan olika kommuner

Discharge of inadequately treated waste water containing nutrients such as phosphorus and nitrogen as well as organic matter and bacteria is associated with a risk of eutrophication and contamination. The Swedish government has decided upon several Environmental Quality Objectives aiming to reduce the emissions of nutrients to water bodies.In Sweden, there are between 675 000 to 1 000 000 on-site sewage systems. Recent studies have shown that the function of small sewage treatment plants is in many cases insufficient. To prevent this regular service and supervision by a professional is needed. The focus of this study are small sewage treatment plants which use a technique where mechanical, chemical and/or biological reduction of pollutants is being used in the same facility to reduce nutrients in household wastewater.The aim of the study is to investigate how different municipalities ensure that small sewage treatment plants fulfill the requirements and reduce pollutants as efficient as the manufacturers claim.

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