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158 Uppsatser om Pollutant removal - Sida 3 av 11
Förstudie till våtmark i Rimbo : Design för optimal hydrologi och kväverening
The euthropthication of the Baltic Sea is a threat that is beginning to be taken seriously by the governments concerned. In Sweden, regulations concerning the allowed nitrogen (N) concentration in the effluent water from wastewater treatment plants are being tightened up. The Rimbo wastewater treatment plant has been imposed to reduce the annual mean concentration of total N in the effluent water to levels below 15 mg l-1. A more and more common way to reduce the nitrogen level in wastewater is to let the water pass through a wetland. This study investigates the possibility to build this kind of wetland at the outlet of the Rimbo wastewater treatment plant.A prestudy of the topography, soil characteristics and groundwater flow indicates that the land area in question is well suited for the construction of a wetland.
Laseria ? hair and tattoo removal : Att skapa en hemsida med anva?ndbarhet i fokus
Denna rapport syftar till att beskriva utvecklingsprocessen fo?r skapandet av salong Laserias nya hemsida. Hemsidans design a?r skapad med anva?ndbarhet i fokus vilket uppna?ddes genom studerande av relevant litteratur samt en fokusgruppsintervju med na?gra av salongens kunder. Hemsidan utvecklades med hja?lp av Wordpress fo?r att uppdragsgivarna pa? egen hand ska kunna administrera hemsidan efter leverans..
V?RMEAKTIVERADE TISSUES P? TRANSPARENT PAPPER En j?mf?rande studie vid revlagning
Works on transparent paper, also commonly known as tracing paper, have been described as ephemeral or temporary working documents and they usually number large quantities in archival and museum collections. They have therefore previously been considered of lower priority and can be found in poor condition due to a lack of treatment or suitable storage prospects. In addition, transparent paper can be very sensitive to moisture and reacts by deformation or loss of transparency. Due to the volume of these works and the necessity of treatment, there is a call for simple and efficient conservation methods. A common solution in archives for the treatment of water-sensitive works on paper has been the use of heat-activated tissues as they can be applied without the introduction of solvents.
There is little published about the use of heat-activated tissues on transparent paper and is mentioned only briefly in existing literature.
Avskiljning av ammoniumkväve och fosfatfosfor i reaktiva filtermaterial : skak- och kolonnförsök
In Sweden more than 400 000 private households have not yet sufficient wastewater purification. These effluent is considered as an increasing problem and many onsite purification methods have been studied. In this investigation, the method of reactive bed filters have been tested by column and batch experiments. Five different kinds of filter materials with reactive surfaces have been studied concerning their capacity to absorb ammonium and phosphorus from wastewater. The materials that were examined are Filtra N, wollastonite Filtra P, blast furnace slag and Polonite®.
Welfare impairment of lambs around weaning. Play and other behaviour indicative of affective state
The abrupt and early weaning of intensively kept lambs may have serious animal welfare implications, but relatively little is known about this. Weaning includes the breaking of the mother-young bond and abrupt replacement of milk by solid food, often coinciding with changes in the (social) environment. Altogether, these changes are likely to affect lamb welfare significantly. This study aimed to establish how strong and persistent lamb welfare is impaired following abrupt weaning by means of measuring behaviour parameters indicative of affective state. Also, we investigated the existence of a diurnal rhythm in play behaviour, which is considered an important indicator of positive affect and good welfare.
Soil carbon, pH and yield development in a long-term humus balance trial
Agriculture has to be performed in a sustainable way in order to sustain high yields and to support a globally growing population. Functional soil properties are fundamental for high yields and in order to achieve good soil conditions sustainable management is a key. Loss
of soil organic material and increased soil acidity are problems associated with degradation of soils and hence less sustainable agriculture. In this thesis, the effect of different agricultural systems on soil organic matter, pH and yield was examined. The systems examined are a cereal system with straw removal or returning and a ley system, all with different nitrogen levels.
Resurseffektiv kvävereduktion genom nitritation
Resurseffektiv kvävereduktion genom nitritationProblematiken med övergödning i våra akvatiska system har lett till hårdare krav på kväverening vid våra reningsverk. En rejektvattenbehandling har visat sig vara ett bra alternativ för att utöka kvävereningen. Vid Nykvarnsverket i Linköping renas avloppsvatten och sedan 2009 finns en SHARON-anläggning i drift. SHARON står för ?Stable High rate Ammonia Removal Over Nitrite? och är en kvävereningsprocess för rejektvatten utvecklad av Grontmij i samarbete med Tekniska universitetet i Delft.I denna studie har SHARON-processen i Linköping undersökts.
Energieffektivisering av luftningssteget på Käppalaverket, Lidingö
This master thesis in energy optimization was made during the autumn of 2006 at Käppala wastewater treatment plant in Lidingö, Stockholm. A preceding thesis, where all electricity consumption was mapped, showed that the aeration in the biological treatment is the single largest consumer in the plant, and it is therefore of interest to reduce this cost. The oxygen control strategy used at Käppala WWTP is working well from a nutrient removal point of view, but not from an economic one. The last aerobic zones have a very low oxygen consumption during low loading periods which give rise to enhanced dissolved oxygen concentrations with excessive costs and reduced denitrification as a result. But also during periods of normal loading unnecessary high oxygen concentration are sometimes given.By modifying the aeration control strategy three full-scale experiments have been made, with the intention to reduce the air consumption.
Reningseffekt i dämd dagvattentunnel i Märsta, Sigtuna kommun : Pollutant removal in a dammed stormwater tunnel in Märsta, Sigtuna municipality
Det vatten som avrinner från hårdgjorda ytor, så kallat dagvatten, innehåller ofta en mängd olika föroreningar, så som tungmetaller och näringsämnen, som kan göra stor skada om vattnet inte renas innan det når recipienten. Ett vanligt sätt att rena detta vatten är genom öppna system, som dammar och våtmarker, eftersom de fungerar både som flödesutjämnare och som sedimentationsmagasin.I Steningedalen, Märsta, finns en dagvattenanläggning med dammar och översilningsytor, vars syfte är att rena dagvatten från ett avrinningsområde på ca 7200 ha. Vattnet leds till dammarna via en dagvattentunnel vars primära syfte var att leda vattnet förbi Märsta centrum. Tunneln är ca 3100 m lång, sprängd och delvis i betong, och har ett skibord installerat i tunnelmynningen med syfte att skapa ett sedimentationsmagasin samt att vid höga flöden leda vattnet förbi dammarna direkt till Märstaån. I denna studie har reningseffekten av denna dagvattentunnel utretts.
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.
Kan perfluorerade ämnen i kläder bidra till förhöjda halter i reningsverk?
Perfluorinated substances (PF) are environmental pollutants that are used to coat fibres of so called ?all weather clothes? to make them water resistant. PF are effectively spread through water. Waste water treatment plants (WWTPs) are a pollutant source of these substances. PF are poisonous to different kinds of organisms, and supposedly also to human beings, if concentrations are sufficiently high.Perfluorinated substances have been investigated at three waste water treatment plants in Stockholm during the 2000?s.
Inventering av förorenade områden enligt MIFO-fas 1 : Erasteel Kloster AB, Söderfors
Erasteel Kloster AB Söderfors have been commissioned by the county administrative board in
Uppsala län to make an inventory of possible contaminations in theirs industrial- and landfill areas on the basis of the Swedish Environmental Protection Agency?s; ?Method of Surveying Contaminated Sites-phase 1? (MIFO-fas 1). The inventory starts with maps and archive studies, place visits and interviews, and finally a risk classification is done. A risk classification is a compilation of four categories; pollutant toxicity, contamination level, possible spreading condition of the pollutant, sensitivity and protection value of the environment.
In this paper five partial areas (Holmen- and Jörsöområdet, Järnsvampsområdet,
Ingsådeponin, Östra verken and Myrområdet) have been described from a historical point of
view. Only parts of four areas have been risk classified (Holmen- and Jörsöområdet,
Järnsvampsområdet, Ingsådeponin and Östra verken), due to that the other areas isn?t own by Erasteel Kloster AB.
Holmen- and Jörsöområdet
Holmen- and Jörsöområdet have during the entire activity time been carried out as the
production core in the company.
Bottensubstrat och dess inverkan på reducering av BOD5, COD och TKN i lakvatten genom konstruerade rotzonsanläggningar : En pilotstudie vid Univates, Lajeado ? RS Brasilien
Treatment wetlands been showed efficient for reducing pollutant in waste water. In Lajeado ? RS, Brazil the landfill has poor leachate water treatment. It is necessary to supplement the treatment plant because they need to reduce BOD, COD and nitrate of the water going to recipient. A subsurface flow wetland (SSF) can be a good choice. In order to be able to design an efficient SSF it is important to understand how the grain sizes of a substrate affect the reducing of pollutants in waste water.
Konstruktiv utformning av vikplog
This project is about investigation and improvement of a V-plow for the company Swekip. A V- plow is used for snow removal but this product has been found to have deficiencies in its construction, breaking down and not living up to the desired objectives. This is because the product is ordered from a company in China where they have some problems with understanding the purpose of the plow.Initially the existing plow is investigated, all the shortcomings set out and examined, what is wrong and what needs improvement?When the solutions were done they were evaluated and examined that they actually live up to the desired requirements.This assignment is a pure construction project where the majority is implemented in CAD, where models are developed and FE analyses are carried out. But the project also includes a feasibility study, idea study and hydraulic design.The results are presented in the form of a CAD model and associated drawings that will serve as the manufacturing basis for the new V-plow.
Visuell utvärdering av frekvensmodulerat raster på obestruket papper.
This thesis investigated if a combination of increased under colour removal (decreasing the total ink limit), normal andincreased density and modern FM-screening could be used to provide a visually better print on uncoated and coated paperin comparison with AM-screening using the same conditions.Two different test groups (one with graphic background, the other with no graphic background) were asked to a visuallyassess the quality of the prints presented in a pair comparison using a reference image.The results show that the FM-screening did not obtain any significant visual difference in comparison with AM-screening,regardless of paper types and density levels. In general however, prints on coated paper were graded higher..