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136 Uppsatser om Removal - Sida 1 av 10

Removal efficiency of perfluoroalkyl substances (PFASs) in drinking water : evaluation of granular activated carbon (GAC) and anion exchange (AE) using column tests, and the effect of dissolved organic carbon

Poly- and perfluoroalkyl substances (PFASs) are a group of environmental contaminants that have gained increasing attention due to their potential to bioaccumulate, environmental persistence and potential toxicity. PFASs have been found in surface water, sediment, air, soil, sludge and ice caps globally, as well as in wildlife and humans. Furthermore, PFASs have also been detected in drinking water, leading to raised concerns for human health, since drinking water is one of the most significant sources of PFASs for the general population. Conventional water treatment techniques have shown to be ineffective removing PFASs, highlighting the importance for further research to develop efficient Removal techniques. The aim of this study was to investigate the Removal efficiency of PFASs in water using two treatment techniques; granular activated carbon (GAC), type Filtrasorb 400®, and anion exchange (AE), type Purolite A-600. Additionally, the effect of dissolved organic carbon (DOC) on Removal efficiency was studied.

The behaviour of foals before and after weaning in group

Weaning is a standard procedure at most studs, and the methods of weaning varies greatly. The method used at the stud in this particular study is supposed to decrease stress. The purpose of the study was to compare the behaviour of foals in group before and after stepwise Removal of their mares. Standardbred foals with their mothers were kept in three different groups at pasture (12, 11 and 11 foals, respectively, mixed sexes). They had free access to silage and the foals were fed concentrate in a creep-feeding area. By the time the foals were 5 months old, the mares were stepwise removed from the pasture.

Skadegörelse klotter nedskräpning förbjuden : Graffitiborttagning som ikonoklasm

This essay concerns graffiti, and in particular graffiti Removal regarded as iconoclasm.Graffiti is described as a visual symbol laden with both negative and positive values, and sometimes as a meaningful expression in the urban public space. One problem with graffiti as a field of study is the diversity of both the meaning of the term as well as the diversity of the phenomenon itself. Therefore I have defined the term graffiti as follows: words and images painted on public walls by a person usually in an unauthorised manner. Specific examples of graffiti and related phenomena are presented. Within the Swedish anti-graffiti discourse the pejorative term klotter (scribbling) is used to describe what I above define as graffiti.

Buskröjning längs skogsbilvägar : en produktivitetsstudie av två kättingslagor

To regularly remove woody vegetation along the roadside of forest roads is an important part of the road maintenance, since the vegetation binds moisture in the road side and, thus, the Removal makes the road drying faster with results in improved bearing capacity. Vegetation Removal also makes it easier to upgrade the road by material recycling from the ditch and, moreover, the visibility along the road is maintained.The aim of the study was to evaluate what type of chain flail is the best and most cost-effective for Removal of different kind of woody vegetation along forest roadsides.Time studies were made on two chain flails when removing woody vegetation in three different classes; easy-, middle- and heavy shrub Removal. The studied flails were one light and rather simple flail named Optimal M160 and a heavier and more advanced flail named Slagkraft H210. The Removal was made according to Holmen Skogs? specification and the quality of the cleaning was measured by objective belt inventory.The productivity was higher with the heavy flail within all cleaning classes.

Phycoremediation of pesticides using microalgae

Every year, pesticides are found in surface and ground waters in Sweden. Fungicides are in common usage and applied in high amounts against potato late blight. The present thesis examined the possible Removal of four fungicides (metalaxyl, cyprodinil, propamocarb and mandipropamid) from water using the microalgae Chlorella vulgaris. Microorganisms are capable of decomposing a range of organic pollutants and the main focus in previously published studies has been on bacteria and fungi. Microalgae are mostly studied due to their high capacity in biosorbing heavy metals.

Reduktion av föroreningar i processvatten från en äggfabrik i Brasilien : Kväve- och fosforrening i anlagda våtmarker.

A water treatment unit consisting of two aeration basins, two settling tanks, a residence basinand a horizontal subsurface flow wetland were used to treat wastewater from an eggprocessing factory in Brazil. The aim of this paper was to determine the efficiency of thesystem in reducing nitrogen, phosphorus, BOD5 and TSS (among other parameters) andgetting a further understanding on different kinds of constructed treatment wetlands as well astheir nitrogen and phosphorus Removal processes. The wastewater from the factory consistedof process water from manufacturing and water used for cleaning, no stormwater or sewagewater entered the system. Tests were taken three times a month from October 2013 ?til April2014.

Mineraliska material som reaktiva filter för avskiljning av tungmetaller från dagvatten

Highly polluted urban storm water from e.g. highways can contain large amounts of heavy metals that may cause harm if they are discharged into recipients. To remove the heavy metals a possible low-cost method that does not require much maintenance, could be the use of reactive filters with filter materials consisting of industrial residues or other cheap mineral based materials. Dissolved metal ions are removed by reactive filters through the processes of ions binding to active sites on the surface of the filter materials, or by formation of insoluble precipitates.The ability of CaO-treated granulated blast-furnace slag, iron oxide coated sand, olivine and nepheline to remove seven heavy metals (Cr, Cd, Cu, Ni, Zn, Pb and Hg) from urban storm water was studied. Initially batch experiments were performed where the effect of pH, dissolved organic carbon (DOC) and dissolved ions on the adsorption efficiency was studied.

Sedimentprovtagning av dagvattendammar som ett alternativ till flödesproportionell vattenprovtagning

Stormwater run-off from surfaces such as roads or rooftops is often polluted with heavy metals and nutrients. Many of these substances can cause great damage in biota if they end up in the recipient. In Sweden constructed wetlands and ponds for treatment of stormwater are frequently used, since research has shown that these treatment ponds are reducing stormwater pollution considerably to a low cost. The knowledge of these pollutant Removal mechanisms and how follow-up and assessment of the ponds should be performed is still limited.To determine the pollutant Removal efficiency of the stormwater ponds it is recommended that flow-weighted water samples are collected from both the inflow and the outflow of the pond. This method demands considerable resources of time and money for installations and analysis.

Hydrolys av primärslam för förbättrande av biologisk fosforreduktion vid behandling av hushållsavloppsvatten [Hydrolysis of primary sludge for enhancement of biological phosphorus removal in household wastewater]

Hammarby Sjöstad is a new district of southern Stockholm built with focus on reduced environmental impact by recirculation of materials and sustainability. The environmental goals aim to cut the water consumption by half and a separate storm water treatment. Thus, the wastewater will be more concentrated and will originate from the households only. The Sjöstad project includes the idea of a local treatment plant for the household wastewater. To evaluate this possibility, Sjöstadsverket, an experimental treatment plant was constructed.

Optimering av biologisk fosfor och kvävereduktion i ett reningsverk för hushållsspillvatten

In connection with Henriksdals wastewater treatment plant (WWTP) a smaller plant is situated called Sjöstadsverket where new methods for wastewater treatment are tested and evaluated in different process lines. On one of the lines experiments with enhanced biological phosphorous Removal (EBPR), have been carried out to evaluate if it is a good alternative to traditional chemical phosphorus Removal. This thesis evaluates the results from the experiments conducted during fall 2005.The incoming water from Hammarby Sjöstad consists of only household wastewater, which gives a wastewater with high concentrations of nutrients and organic carbon. This is partly positive, because one of the limiting factors for effective biological phosphorus Removal is the lack of easily biodegradable organic carbon. The high concentrations of ammonium and phosphorus demand a high reduction to achieve the requirements of outgoing concentration.To optimize the process experiments with different recirculations and different aeration techniques have been made.

Rimbo våtmark : en förstudie på förväntad kväveavskiljning och lämplig växtlighet

This study was made as a part of a feasibility study on a polishing wetland at Rimbo wastewater plant (wwp) in Norrtälje municipality. The wwp had to decrease the nitrogen discharge to reach the limit 15 mg tot-N/l. The nitrogen in the outlet was mainly in the form of nitrate, hence the wetland mainly ought to support denitrification. The proposed area for the wetland was situated right next to the wwp and was already in the municipalitys posession. One aim of this study was to examine what spieces of plants needed to achieve highest possible denitrification.

Urlakning av järn ur arkeologiskt trä med dietylentriaminpentaättiksyra (DTPA): undersökning av koncentrationens påverkan på extraktionstakten

Uppsats för avläggande av filosofie kandidatexamen i Kulturvård, Konservatorsprogrammet 15 hpInstitutionen för kulturvårdGöteborgs universitet2015:06.

pH-sensitivity in boreal streams ? the influence of landscape characteristics

The goal of the society to increase the proportion of renewable energy has led to an increased demand of bioenergy e.g. forest biomass. However, there are concerns that Removal of biomass will lead to decreased base cation concentrations in the soils and acidification of streams. In order to find in which types of landscape Removal of branches and tops could have such negative effects, this study aims to analyse the relations between pH-sensitivity and landscape variables in the Bothnia Bay water district. GIS and digital geographical data were used to analyse the landscape in subcatchments.

Avskiljning av uran från dricksvatten med reaktiva filter :

Water is our most important provision and its quality is above all dependent on the geological conditions in the area from where it is extracted. Due to geological properties there are certain areas with an elevated risk of high uranium levels in the ground water, which in turn constitutes a risk for human health. Consumption of water that contains a high concentration of uranium implies a health risk due to the chemical characteristics of uranium. Livsmedelsverket (The National Food Administration) and Socialstyrelsen (The National Board of Health and Welfare) therefore recommend that precautionary measures should be taken when the uranium concentration in ground water exceeds 15 micrograms per litre. In particular, drinking water collected from wells in areas with uranium-rich bedrock may have a harmfully high level of uranium. One of the wells of the Ärla water purification plant, located near Eskilstuna, Sweden, contains water that exceeds the guideline of 15 micrograms per litre. One interesting technique for removing uranium from drinking water is adsorption to reactive filter materials.

Effekter på antalet vårdrelaterade urinvägsinfektioner av nya rutiner för kateteranvändning

Introduction Every tenth patient in Sweden is affected by nosocomial infections. Among these, urinary tract infection (UTI) is the most frequently occurring within the hospital environment. Nosocomial infections lead to increasing costs for care, more suffering among the patients, increasing use of antibiotics, and longer treatment spells. The Academic hospital have engaged all wards in the so called VRISS-project (?nosocomial infections must be stopped?) in order to reduce the number of nosocomial infections.Aim In connection to the VRISS-project new routines for Removal of uretrahl catheters are introduced at ward 70E2 at the Academic hospital.

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