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1319 Uppsatser om Reject water - Sida 25 av 88

Perkolationsfilter : En undersökning av reningseffekt med avseende på järn och mangan

This master thesis has been done in cooperation with Sweco Viak AB in Sundsvall. The aimwith the project is to investigate the purifying effect of percolation filter due to iron andmanganese. The overall goal was to investigate how the parameters surface load,sandfractions, and burden time affect the purifying effect. The expectation is to optimize thedesign and find a demouldning of the filter that gives sufficient purifying with a highersurface load. As an attempt to accelerate the curing of the filter, experiments with a layer ofsand which surface has been covered with manganese ore (MnO2) on top of the filter havebeen done.As test filters 10 L bars were used and the experimental work was performed at thewaterworks in Hassela and Munkbysjön.In Hassela different sandfractions were tested.

The bioavailability of soluble oxalates in stir-fried silver beet leaves

The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.

Förändringar i markanvändning över tid och dess påverkan på vattenkvalitet

The EU Water Framework Directive has led that management follows the boundaries of natural catchments.The Swedish waters suffer from a nutrient overload that originates mainly from diffuse sources such as agriculture and the subcatchment of Hackstabäcken in Vallentuna Kommun, just north of Stockholm, has been chosen for this study because of its high nutrient load and because it has undergone obvious changes in land use through the years.In this study, the land use in 1902 is compared with the land use in 2011 in order to investigate if it has influenced the ability of the landscape to produce ecosystem services related to nutrient removal. These services will continue to be produced as long as the system is stable and resilient, but when landuse changes and manure from horses increases it will lead to disturbances that can convert a system from one regime in to a completely different one. That will result in loss, or degradation, of ecosystem services such as denitrification, phosphor sedimentation and adsorption, vegetation uptake and infiltration.The results of this study are based upon area calculations of landuse from old maps from 1902 and 2011. Through these maps it becomes clear that the forests in Hackstabäcken, has increased with 170 ha together with an urbanization of 311 ha, at the same time as wetlands and arable land has diminished and lakes has suffered from reductions. Wetlands have been reduced with 76 ha and the ones remaining are of insufficient quality from a nutrient removal perspective.Data from 1902 and 2011 regarding number of horses and bovines indicated a decrease in bovines and an increase in horses.

Utvärdering av jetomrörning : En studie gällande utvärdering av omrörningssystem vid Ekeby reningsverk

Biogas is a renewable energy produced through anaerobic digestion, which means that organic matter is degraded by microorganisms under anaerobic conditions. The produced biogas can then be used for cogeneration, electricity, heat or upgraded to vehicle gas. Eskilstuna Energy & Environment AB has four digesters at Ekeby water sewage treatment plant, Eskilstuna. One of the biogas reactor (RK4) is equipped with a jet-mixing system while the remaining digester uses top-mixing. The mixing system is an important parameter to achieve optimum operating conditions for the process regarding gas production and degree of digestion.

K2-regelverket : En empirisk studie om varför företag inte väljer att tillämpa BFNAR 2008:1.

Purpose: The purpose with this empirical study is to investigate how many companies have chosen to apply the K2 framework and see why the remaining companies have chosen not to.Methodology: A choice of a quantitative approach has been applied to collect information and create a foundation for the problem. Furthermore a qualitative approach has been selected to cover the remains.Theoretical perspective: This section contains a presentation of the agency theory, the institutional theory, the k-project and a comparison of K2 and the existing regulation.Results: Three out of 143 companies applies BFNAR 2008:1. 13 out of 143 companies use self-generated intangible fixed assets. Out of 29 contacted companies only three know about K2. The 29 companies are from various lines of business within an area.Conclusion: The conclusion of our research is that the majority of the companies did not reject to use the K2 regulations.

Nitrogen flow in Scania : substance flow analysis on a regional level

In this thesis, the flows of reactive nitrogen (Nr) in Scania were investigated and quantified. The thesis was also intended to form a basis for comparison between the urban nitrogen flow and other flows of nitrogen within Scania. The management of nitrogen in society has disturbed the natural nitrogen cycle. This is linked to a series of environmental problems such as eutrophication, acidification, global warming and smog. The method used was Substance Flow Analysis (SFA) for Nr. For calculation and flow charts Scania was divided into three subsystems; air, water and society.

Uthållig sanitet : en förstudie i staden Picota, Peru

The access to good sanitary facilities is an important factor that elevates the experienced living standard as it improves hygiene and reduces the transmission of deseases. The ratification of the millennium goals by 189 countries demonstrates that this is an important international issue. Together the countries have taken upon themselves that the proportion of the population that lacked access to sustainable safe drinking water and sanitary facilities in the year 2000 will have been reduced by half by the year 2015. In Peru, the construction of sewage pipe networks to transport the sewage out of the direct human environment is progressing. The safety and sustainability of these systems can be questioned, since in Peru the sewage seldom receive any treatment before being emitted to a recipient. This is taking place in Picota and sorrunding villages as well. In the last 25 years several systems implementing small-scale onsite treatment have been introduced throughout Latin America in an attempt to give more people access to sustainable and safe sanitary facilities, reducing water consumption and taking advantage of the agricultural values of the sewage fractions while protecting the environment from its negative impact. In this study three different sanitary systems and the effects of different population growths were compared.

Water balance and nitrate leaching from arable land in a changed climate : a model study

This thesis aims to present the essential background on how to perform climate changeimpact assessments, and to present the results from a climate impact assessment on waterbalance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwesternSweden, grown with spring cereals. This study is meant to be a benchmark example,and cannot be seen as a regional or national assessment for Sweden, rather as an approachto present and analyze the most important parts of these kinds of assessments.A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for thisstudy. The model was parameterized and calibrated against data from an experimental site,located in Mellby in Hallands county, south western Sweden. Measurements were carriedout between 1st of April 1988 and 1st of April 1991.

Analys och förbättring av en mätenhet för laddning av elfordon

Reducing the CO2-pollution, resulting from the combustion of fossil coal for energyproduction, is important to affect environmental changes. One way to achieve a reductionis to use the oxy-fuel technology. The technology uses O2 and re-circulated flue gasduring the combustion which results in a flue gas mainly consisting of CO2. The flue gascould then be compressed and stored without environmental effects. A problem thatfollows from the compression is the risk of acidification in sensitive parts of the process.Acidification can occur because of reactions following from the contact of condensedwater and sulphur- and nitrogen-oxides which are also present in the flue gas.This report compiles and evaluates the basis of a scientific unit with the purpose ofexploring the possibilities of extracting impurities of SOx and NOx from the flue gases.The dimensions of the unit are based on basic conditions, defined for an existing oxy-fuelprocess at Chalmers, and on the results of computer modelling.

Analys och gestaltning av miljön kring vattentornet i Uppsalas stadsskog

The water tower in Uppsala city forest was built in the late 1950's in what is now a nature reserve. The unique place was supposed to be visited by people, which is currently not the situation. This bachelor thesis aimed to perform an analysis and make a design proposal for the environment surrounding the water tower. The analysis was performed using the methodology previously described by architect Arne Branzell. The methodology focuses on how a space is perceived by a person moving through it.

Sjöars känslighet för klimatförändringar ? vilka faktorer påverkar?

The Earths climate is changing at a higher rate, i.e between 1861 and 1994 the annual mean temperature in Scandinavia increased with 0,68º C and according to recent climate models the annual mean temperature is likely to rise with another 3º C during this century.A warmer climate in many ways is associated with changing conditions for lake ecosystems. An expected higher water temperature and a stronger summer stratification of the water column increases the risk of anoxic conditions at the lake bottom. Thus anoxic conditions are likely to cause a phosphate leakage from the sediment, i.e. a higher internal loading of phosphate.In this project, the extremely warm summer of 2002 has been used as an example for a possible scenario for a future climate. By comparing levels of phosphorus in the summer of 2002 with a ten-year median value, a phosphorus related sensitivity to climate change has been analyzed for 55 Swedish lakes.

Miljösystemanalys av alternativa avloppssystem i ett urbant område ?Svartvattensystem : Skogaberg ? Ett pilotprojekt i Göteborg

Starting point to this Paper is the idea and wish to adapt the society and its different activities to a recycle society. A building area in Göteborg is planned and investigated for such adaptation. In the district named Skogaberg, about 130 households totally are planned from what 20 are blocks of flats. The idea with this project is to constitute an alternative sewage system, a Blackwater system, were the fractions of most nutrients and least pollution are separated, taken care of and utilised. The aim is to get a market and use the nutrients of the organic waste from the household in agriculture use.

Föroreningstransport i grundvatten : En modelljämförelse

This thesis compares different methods for risk assessment of a creosote contaminated site in Vansbro, Dalarna. In a complementary study the importance of using representative data for calibration and validation of stationary groundwater models is discussed. The time dependency between surface water levels and groundwater levels on the site in Vansbro is evaluated by step response analysis. The results show that the groundwater levels reflect only long-term variation in the surface water levels. Hence the use of such long-term means for calibration and validation of the stationary groundwater models is the only theoretically defendable alternative.As a first step in the comparison of risk assessment methods the degree of contamination is evaluated on the basis of generic guideline values for contaminated soils, developed by the Swedish Environmental Protection Agency.

Tillagning i mikrovågsugn och dess effekt på livsmedel : En jämförelse med konventionell tillagning

Microwave is a time- efficient device for heating and reheating of foods. Despite the fact that its effects on foods have been evaluated during a long period of time, without any more negative effects shown compared to conventional cooking, one third of the Swedish population believes (in 2010) it accounts for a higher loss of nutrition. This literature review aim to compile studies regarding how food is affected by cooking in microwave, with respect to cooking losses, nutrition, secondary metabolites as well as sensory and textural aspects and compare it with conventional cooking. The compilation shows that different combination of effect (W), time and amount of water during microwave cooking have different effects on foods. The contents of proteins, vitamin B and carbohydrates are generally higher after microwave cooking, while anti-nutritional substances are affected much less during conventional cooking. This also depends on if it is of animal or non-animal origin. However, for the majority of nutrition values the differences are quite small.

Vindpark Vänern : Fundamentteknik och Logistik

An analysis of a specific application of anaerobic wastewater treatment at a pulp and board mill, Stora Enso Skoghall, was carried out. A literature study was done and effluent wastewater from CTMP pulp production was analyzed. The analysis consisted of a broad constituent analysis and an anaerobic treatment trial. Results from these test where used to calculate the treatment effectiveness and resulting energy potential at the mill.The literature study and constituent analysis showed that toxicity of the water to be treated, due to wood extractives and sulphur content, was of concern. Detoxification chemicals targeting these constituents where used in the anaerobic treatment trial.

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