The aim of this thesis is to improve the control of urea injection at the combined power and heating plant Framtidens Gärstad (FTG). Tekniska Verken i Linköping AB is the owner of the plant.The FTG plant consists of a boiler where garbage combustion is done. From the combustion nitrogen oxides are emitted. These nitrogen oxides are hazardous to the environment. To reduce the nitrogen oxides, injection of urea into the boiler is used.

Due to global climate change and the rising levels of greenhouse gases (GHG) in the atmosphere, the interest for seeking solutions for mitigation has increased. While much attention has been directed towards technical solutions such as carbon capture and storage (CCS), biogenic carbon sinks has also garnered significant attention. Previous studies have shown that coastal ecosystems such as seagrass meadows and mangroves have a much greater capacity for storing carbon (C) compared to terrestrial ecosystems. That raises the question if other coastal ecosystems, such as coastal wetland forests, that previously haven?t been considered as blue carbon habitats also contribute to coastal carbon sink capacity.

Background Anesthesia-related deaths are common in dogs, especially in the postoperative period, in compare to humans. This study aims to describe and elucidate the qualities of the postoperative care for dogs in Sweden. Method To investigate the postoperative care, a qualitative study was made by interviewing personnel in the animal health care sector. The primary information from the interviews was analyzed in a qualitative manor and a few distinguished qualities came forth. Results These qualities describe the postoperative care and include preventive activities, postoperative activities, monitoring and communication. A variation in regards to the results was seen between the interviewed.

Eutrophication is an environmental problem that affects more than ten percent of Swedish lakes. Excess nutrients increase the growth of algae, and cause major problems in the ecosystem through Oxygen-free bottoms, fish kills, and at worst dead bottoms. Agriculture accounts for 44% of human emissions of phosphorus to lakes and rivers. Leaching occurs of particle bound phosphorus and of dissolved phosphate. The amount of phosphate in the soil solution that may be leached is partly due to the prevailing pH in the soil solution. The purpose of this study was to investigate how the relationship between phosphate solubility and pH was affected by liming.

Emissions of insufficiently treated wastewater, mainly blackwater (i.e. wastewater from toilets), contributes to the eutrophication of lakes and seas. At the same time, blackwater is a fraction with a low content of heavy metals and, after sanitization, it can recirculate plant nutrients to arable land using the liquid composting treatment method. Liquid composting means that organic material is degraded under aerobic conditions. For sanitization, the blackwater needs to be treated together with energy-rich complementary material.

Detection of leukocytes in semen from boars is part of the routine control of semen quality. Leukocytes in semen can cause damage to spermatozoa that leads to impaired fertilization. In the artificial insemination (AI) industry there are standard routines for the quality control of the boars and of the neat semen before use. Since 2001, Quality Genetics has not done the leukocyte examination on semen samples from boars which are used for the production of pigs for slaughter. The purpose of this study was to investigate the occurrence of leukocytes in semen from AI-boars. The questions addressed were whether there are boars that have leukocytes in their semen and how frequently it occurs and, moreover, if there are differences between breeds, or even between individuals whose semen was checked before use in AI-dose production compared to those which were not. The study included a total of 135 AI-boars, of which 67 were Hampshire, 35 Yorkshire and 33 Landrace, all belonging to Quality Genetics AI-station in Hållsta.

A study has been performed that investigates the variation of iron content in groundwater.The study was initiated by Midvatten AB, which noticed that the iron content in groundwater samples can vary greatly over small distances. The purpose of this study was to geochemically and geohydrologically determine the factors that influence the content of iron and manganese in groundwater from a selection of eskers in Dalarna, and determine how to best sample groundwater with the method used by Midvatten AB. An evaluation was made of how the vertical variation in soil material, water composition, pumping time and pipe material affects the content of iron in groundwater. Piper diagrams were used to study the relationship between the chemical composition of the groundwater and the content of iron and manganese in groundwater samples from the studied areas. The groundwater from the studied areas was then classified in the Piper diagrams, according to the content of the major ions.

During the 19-century a global warming has been observed, which includes increases in global air and ocean temperatures, widespread melting of ice and snow, and rising global sea level. There is a clear connection between emissions of greenhouse gases caused by the human and the increase in temperature. Climatic changes caused by global warming can be stopped trough decreased emission of fossil fuels, for example by an increased use of biogas. Biogas is a renewable energy source which is produced through anaerobic (Oxygen free) digestion of organic material. The gas is a mixture of methane (CH4) and carbon dioxide (CO2) and can be among others used as fuel in vehicles.

The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment. The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake. Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.

From embankment dams is something that has long been noticed and given rise to different questions. The most serious question is if the sludge is a result of inner erosion through the dam, and thus consists of material transported from the dam. Concerns have also been raised whether the sludge could interfere with the systems drainage capacity and thereby lead to high pore pressure in the dam, or if the measurement of seepage is disturbed, as the measuring is usually made via Thomson weirs, which could risk being blocked. The result of this investigation shows that the sludge is a result of the oxidation of iron by iron bacteria, and to the greater part consists of these oxides as well as the bacteria?s own structures. The iron oxidizing bacteria, FeOB, oxides ferrous iron to ferric as a part of their metabolism, and thereby create large quantities of iron(oxy)hydroxides.

Oilseed rape constitutes a good break crop within a cereal dominated cropping system. The normal sowing time for winter rape in Sweden is August. It's a time in the cropping year characterized by a heavy work load, such as harvest and soil management. In addition, it is often a period with large precipitation. Thus, it is sometimes problematic for the farmer to do the sowing of winter rape at the optimal time.

The nitrogen cycle in freshwater bodies is complex and consists of many separate processes affected by a number of important factors for example Oxygen concentration in the water, temperature and circulation. Knowledge of the different components of the nitrogen cycle exists; however, a complete and comprehensive picture is difficult conceptually as well as theoretically. The available literature illustrates that the research on nitrogen and the related freshwater processes is still associated with high uncertainty of how much of the supplied nitrogen from the catchment is transported with the water versus and how much is lost due to denitrification, sedimentation or uptake by plants. This report is an interdisciplinary survey of Nitrogen discharge permitting. The research focuses in particular on the decision-making process, the levels of scientific standard and the administrative framework.Application for Nitrogen discharge permits are decided by the Environmental Court with council from their own experts as well as relevant government authorities and organisations.

Lower energy use in buildings is a result of increasingly stringent energy requirements across Europe. When conventional district heating technology is used in areas with low energy consumption heatlosses do not fall even though the amount of energy delivered is reduced. This reduces income for thedistrict heating company. To maintain their economic viability the district heating companies? majorchallenge is to implement new solutions that minimize heat loss.

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.

In connection with the admittance of the EC-directive (99/31/EC) in Swedish politic, through the constitution of waste depositing (2001:512) at year 2001, the rules about management the landfills and leachates tightened. At the landfill Vissberga in the municipality of Hallsberg, a leachate treatment plant was constructed just a year thereafter. This treatment plant consisted of an aerated pond with a following land treatment and a willow cultivation to replace the land treatment during the summer. In this case the parameters, which were estimated as the most important to reduce, were iron and nitrogen. The iron would react with the Oxygen-rich water in the aerated pond and precipitate to ferric-hydroxide and than settle in a calm zone of the pond.