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49 Uppsatser om Nitrous oxide - Sida 1 av 4

Avgång av lustgas från luftningsprocessen på Käppalaverket

The requirements for wastewater treatment plants (WWTP) are gradually increasing, partly because of higher incoming loads, which in turn require a more efficient treatment process. In parallel with environmental and economic goals there are also desires to lower energy consumption without compromising the wastewater treatment. Furthermore, there is a demand on WWTP´s to alter eutrophication in aquatic systems through better nitrogen and phosphorus removal. An increasing number of WWTP´s have acquired biological nitrogen and phos-phorus removal. A by-product of this type of biological treatment is the formation of Nitrous oxide, which is a potent greenhouse gas.

Tillsats av biokol till en svensk sandjord : effekter på lustgasavgång, kväveretention och andel vattenfyllda porer

In a column experiment the effect of three different biochars on nitrous gas emissions, nitrogenretention and water filled pore space (WFPS) were studied in a Swedish sandy soil, classified as aCryopsamment. Ammonium retention was positively correlated, while KCl-extractable ammoniumwas negatively correlated, with the specific area of the biochars. The question was raised whether thenegative correlation between extractable ammonium and biochar specific area reflects the amount ofammonium present in the soil or its extractability from the biochar, and whether methods forextracting soil mineral nitrogen, like KCl-extractions, have to be modified for application on biocharamended soils. There was a tendency of increased nitrate retention and KCl-extractable nitrate withbiochar and KCl-extractable nitrate was positively correlated with the specific area of the biochar. pHwas higher for all biochars compared with control, although the differences were not significant, andWFPS was lowered by biochar addition, significantly in one case.

Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark

This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of nitrate and the emission of Nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.

Stubblyftningens initiala effekt på emissioner av växthusgaser från en granmark i Småland :

In order to reduce greenhouse gas emissions from human activities fossil fuels will have to be replaced with renewable energy alternatives, such as bioenergy. Sweden has a great potential to produce bioenergy derived from forest products and there is currently a great interest within Sweden in using stumps for bioenergy production. However, the environmental consequences of the method need to be investigated before stump removal can be performed on a large scale. Swedish forest soils contain large carbon pools and a different land use may change conditions so that soils that presently act as sinks of carbon could potentially turn into sources of carbon release instead. This study investigates the initial effects of stump harvesting on the emissions of three greenhouse gases, carbon dioxide, methane and Nitrous oxide. The emissions were measured from the soil surface in a Norway spruce forest located in the southern part of Sweden.

REE-förande fosfater i Blötbergets apatitjärnmalm

The Blötberget deposit is situated in the north-western part of Bergslagen. The mineralization is an apatite-iron oxide ore of Kiruna type. In Bergslagen the apatite-iron oxide ores occur along a zone from Grängesberg through Blötberget to Idkerberget in the northeast and they represent the largest and the most important iron oxide deposit in Sweden, south of Norrbotten.Different REE hosting phosphate phases has been studied by optical microscopy and analyzed by EDS attached to an electron microscope.The key minerals other than iron oxides are apatite, monazite and xenotime. The relative concentration of the REE-bearing phases differs from the other apatite-iron oxide mineralizations in the area, for example Grängesberg, by a higher concentration of xenotime and lower contents of allanite..

Kväveförluster och energianvändning på mjölkgårdar i västra Sverige :

Protecting the environment has with time grown to take a more central role in the society. Agriculture plays an important role in the society since this sector produces our food. More thorough research on how agriculture affects the environment is therefore motivated. This research can be used to improve the agricultural practice from an environmental point of view. This is something that both the farmers and the consumers can profit from. This study aims to form the basis for creating environmental indicators for use of nitrogen and energy on dairy farms. Twenty-three farmers in western Sweden have been interviewed about their farms, both organic and conventional. They produce milk with different intensity, defined as the amount of milk delivered (sold) per hectare of arable land.

Böklåda med torv på rastgårdsytan i ekologisk slaktsvinsproduktion : effekter på beteende och emission av kväve (NH3 och N2O)

In organic animal production, synthetic amino acids are not allowed. Therefore, a higher level of crude protein is needed in the diet to pigs, which lead to more nitrogen (N) excreted in the faeces and urine. N can be emitted to the air in the form of e.g. ammonia (NH3), which contributes to eutrophication and acidification and as Nitrous oxide (N2O), which is a very potent greenhouse gas. The emission of N can be reduced by e.g.

Pulsed inhaled Nitric Oxide - a possible way to treat hypoxemia in colic horses during abdominal surgery

The aim of the present study was to evaluate if pulsed inhaled nitric oxide (PiNO) could be used as a treatment for hypoxemia during general anaesthesia in colic horses. Previous studies have shown a positive response in horses receiving PiNO in comparison to controls, but these studies have only included healthy individuals. A total of 30 horses were included in this present study, they all underwent abdominal surgery because of acute colic that could not be medically treated. Fifteen of the horses received PiNO and 15 horses served as a control group. Arterial oxygenation was improved in all horses receiving PiNO.

Protesutveckling

This report investigates the possibility of developing a new and improved hip prosthesis. The result were five different materials that could be used for the prosthesis. These five solutions were Silicone Nitrate on Cobolt Chrome, phase stabilized Zirconium Oxide on Cobolt Chrome, Silicone Nitrate on Silicone Nitrate, DLC coated phase stabilized Zirconium Oxide and Chromium nitride coated Cobolt Chrome on Cobolt Chrome. In addition to this it was also investigated how to best market the prosthesis and how to transport them from production sites to hospitals..

Barns upplevelse av lustgasbehandling : En intervjustudie

Syftet med denna deskriptiva kvalitativa intervjustudie var att beskriva barns upplevelser av lustgasbehandling. Urvalet består av sex barn i åldern sex till fjorton år som behandlats med lustgas vid procedursmärta, akut eller planerat, på barnsjukhusets akutmottagning eller allmänna specialistmottagning. Intervjuerna analyserades med kvalitativ innehållsanalys. Alla barnen upplevde annorlunda kroppskänslor eller abstrakta känslor som inte nödvändigtvis var obehagliga under lustgasbehandlingen. Samtidigt som flera av barnen beskrev en typ av frånvaro var de flesta medvetna om omgivningen och till viss del händelseförloppet.

Mikroskopering av opaka faser - en studie från Skyttgruvan, Falun.

In nature there are about 4,500 minerals identified. These can roughly be divided into two groups, opaque phases and non-opaque phases, with the exception that some opaque phases also may act as a non-opaque phase in different circumstances. The division is made on the basis of the optical properties. Opaque phases are nontransparent, which means that a different type of microscope must be used. A conventional microscope uses transmitted light while the microscope for opaque phases or the ore microscope uses reflected light.

Livscykelanalys av en ekologisk bomullsskjorta - miljöpåverkan från vagga till grav

This study includes a life cycle assessment, LCA, on an ecological produced cotton shirt for the company Reflective Circle, which designs ethical and ecological clothes.Initially were cotton farming and textile production studied to gather basic knowledge about the processes. Since this shirt is being ecological produced in the whole production chain, we studied what an ecological production means, but also how a conventional production works. When this was done we could start to discuss the differences and similarities between the production of the shirt and general conventional production.When the LCA was first initiated, the main focus was on the green house gas emissions from the manure at the cultivation. Thereafter the process steps such as picking, ginning, carding, spinning, weaving and sewing were being studied. The picking is done by hand, but the rest of the processes are handed by machines which consumes energy.

Skrubberavfall : Hantering i hamn

This paper deals with challenges associated with handling scrubber waste in the port of Karlshamn and what various industry partners are doing to meet this growing demand. The main challenges have been the proportion of ships with scrubber, the amount of generated waste and waste characterisation. An understanding of these factors has been crucial in order to ascertain the aim of this study, which has been made with calculations based on leading manufacturer?s scrubber analyses and with an estimation of the quantity of ships with scrubber by examining AIS data from the Port of Karlshamn. In order to calculate the quantity of scrubber waste two different scenarios were established, which in turn produced two different outcomes.

Mineraliseringar utmed REE-linjen i sydvästra Bergslagen

This paper briefly summarizes Bergslagen as a bedrock province in order to give background to the genesis and presence of REE-bearing minerals (short for Rare Earth Elements) in the region. These mineralizations mainly occur along the REE-line, a line aproximately a hundred kilometers in length between Norberg in the north and Nora in the south with a width of a few kilometers. Situated in the southwest of Bergslagen it is currently one of only a few places in Sweden where REE-bearing iron oxide mineralizations are potentially economically viable for mining. Ore microscopy has been conducted in order to characterize an ore sample from Myrbacksfältet, one of few sulphide rich iron oxide mineralizations within the REE-line. Additionally, an electron microscope analysis of a sample from Stålklockan, a suspected REE-bearing mineralization also within the REE-line was confirmed by EDS (short for Energy Dispersive Spectrum) analysis.

Spårtaxisystem i Uppsala

An increased awareness about the global warming has created a demand for more information on how the climate is affected by different activities.This master thesis was initiated by Tricorona, a Swedish company that offers its customers analysis and calculation of their climate impact. Tricorona also supplies climate neutralisation with CERs, in accordance with the Kyoto protocol and controlled by the UN. This work demands updated emission factors for greenhouse gases. An emission factor gives information about the greenhouse gasintensity of a service or a product [kg CO2-eq./ functional unit].The purpose of this thesis is to examine how electricity, district heating, hotels, taxis, food and materials affect the climate and how emission factors for these areas can be calculated.This was done by reviewing and comparing different studies and by interviewing experts. The information was evaluated and recommendations on calculations and emission factors were made.The consumption of energy is the main source of greenhouse gas emissions for district heating, electricity, hotels, taxis and materials.

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