Sök:

Sökresultat:

1660 Uppsatser om Water purification plants - Sida 41 av 111

Predicting spawning bed erosion and longevity : a case study in tributaries to river Vindelälven, northern Sweden

Timber floating operations in Scandinavia during the 19th and 20th centuries has contributed to severe negative impacts on riverine ecosystems. Increase in water velocity and lack of stream bed heterogeneity as a result of stream channelization lead to increased bed load transport. Since availability and recruitment of new suitable spawning substrate in Scandinavian watercourses is sparse, spawning habitats for salmonids has become a scarce commodity. Lately, increasingly more attention has been given to the recreation and improvement of brown trout (Salmo trutta) spawning habitats in restoration projects. While much of the research on spawning habitat has been focused on evaluation of the influence that the constructed spawning grounds have on fish populations, few studies have been conducted to evaluate the persistence of these constructions over time. I evaluate erosion of constructed spawning beds as an effect of sediment transport attributable to water discharge.

Urinsorterande toaletter : rensning av stopp samt uppsamling och attityder

It is important that the current urine separating systems are evaluated to allow improvements to be made and consequently increase their future propagation. In order to increase the knowledge about urine separating systems this study was made. It included, among other things, measurements of amounts of urine as well as of the composition of urine collected at Nytorgsgatan 4 in the city of Hallsberg. The study was increased after an inquiry that also included the district of Understenshöjden in the city of Stockholm. In the inquiry, the users were asked questions about odour, cleaning of toilets and occurrence of blockages in the urine water locks etc.

Development of a method for determination of pesticide residues in honey using liquid chromatography tandem mass spectrometry

Honey is a product that may contain pesticide residues due to contamination from bees pollinating various plants as well as elimination of vermin inside the hive. Different methods are needed for analysis of pesticides, since the term includes a wide range of different substances. National Food Administration lacks a validated method for determination and quantification of pesticides in honey using liquid chromatography tandem mass spectrometry, LC-MS/MS. The technique is especially important in analysis of polar and non-volatile pesticides, where gas chromatography is not functioning optimally. After investigating what pesticides could be found in honey produced in Sweden, a number of four pesticides suitable for analysis with LC-MS/MS was compiled; boscalid, impidacloprid, tau-fluvalinate and thiacloprid.

Avloppsvattenbehandling med membranbioreaktor : En jämförande systemanalys avseende exergi, miljöpåverkan samt återföring av närsalter

In the pilot plant at Hammarby Sjöstad, Sjöstadsverket, several new methods are tested in order to achieve a good use of resources. When a new technique is considered it is often the performance of the technique itself, under given conditions, that is evaluated. However, in order to evaluate the overall function the whole picture is needed. With a system analysis it becomes possible to make a comparison where all the positive aspects are put up against the negative ones, for the technique itself as well as its requirements. In this way the influence that minor components have on an entire system can be considered.This report presents a system analysis of an anaerobic membrane reactor (MBR) with a VSEP-membrane (Vibratory Shear Enhanced Process).

?Nu förstår jag!? : En undersökning om hur barns förståelse för vattnets väg till kranen kan utvecklas genom en pedagogisk aktivitet

Syftet med det här examensarbetet var att undersöka 3-5 åringars förmåga att utveckla sin förståelse för vattnets väg till kranen genom med en pedagogisk aktivitet. Genom den pedagogiska aktiviteten gavs barnen möjlighet att färdas genom vattensystemet med sina kroppar och sinnen, från sjön till kranen. För att kartlägga hur barnens förståelse utvecklats genomfördes kvalitativa intervjuer före och efter den pedagogiska aktiviteten.Jämförelsen mellan resultaten av förintervjuerna och uppföljningsintervjuerna pekar på en tydlig utveckling av barnens förståelse av vattnets väg till kranen, som ett tekniskt system. Flera av barnen utvecklade sin förståelse för att vårt hushållsvatten måste genomgå en reningsprocess, färdas genom olika komponenter i vattensystemet och rör innan det slutligen når kranen och kan förtäras..

Tungelsta med trädgårdstema :

In this project, an area in the small town Tungelsta south of Stockholm, is in focus. Tungelsta is placed in the municipality of Haninge and it is for the planning department on the municipality, this project is made. The task is to compose an arrengement of buildings and open spaces for a 50 hektar area. Today the area is consists of agriculture fields and forests. The area is placed near the railway station, in the city centre of Tungelsta, which makes it interesting and important to work with. There are different opinions about the future plans for the area.

Översvämningsrisker längs Funboån

Flooding events are no longer rare, floods occur all over the world. Accordingly, it is vital for the society and different authorities to work with flood mapping. To meet the goal of Uppsala kommun to map the risks of floods in Uppsala län, a map of the different areas around Funboån which are inside the area of risk for flooding have been developed.In the work, cross sections and the water flow have been measured. Moreover, an echo-sounding have been carried out in Funboån to map the bottom topography. From the bottom map and laser scanned data covering the study area, a terrain model was created.

Beräkningsverktyg för plattformar till seriekompenseringsanläggningar

ABB is one of the world?s leading engineering companies in power and automation technologiesand their solutions improve performance while lowering environmental impacts for energycompanies and industries. ABB FACTS designs equipment and plants for series and phasecompensation.This thesis has been performed at ABB FACTS on the Mechanical Design (DM) department inVästerås, Sweden. The purpose of the thesis was to develop and design calculations andsimulation tools for ABB FACTS?s standard series capacitor platforms.

Design av försöksanläggning för trycksatt rökgasrening vid oxy-fuelförbränning

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.

Smak och konsistens hos ost : en litteraturstudie kring årstiderna och fodrets inverkan

To enjoy the richness of the grazing cows and high yield during the summers, even during the winter, cheese has been the way to store milk for thousands of years. Nowadays yield is high all year around and the cheese production is possible during all seasons. The aim of this paper is to investi-gate how and why the seasons influence taste and texture of pressed and ripened cheese. Milk is composed of proteins, fat, lactose and water but contains also a lot of vitamins. The quality of milk is very important for the final constitution of cheese.

Minimera färgbortfall vid vattentvätt inom textilkonservering Med användning av cyklododekan, tvålagersmetoden eller ultrarent vatten

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2014:26.

Utsläpp av växthusgaser under islossning i små boreala sjöar

Freshwater ecosystems have long been neglected as an important part of the global carbon cycle. However, research shows that most of the world?s lakes are net-heterotrophic and consequently emitters of greenhouse gases to the atmosphere. In many boreal and north-temperate lakes, most of the yearly emissions usually occur in spring, shortly after ice-thaw. The aim of this study was to quantify the flux of carbon dioxide (CO2) and methane (CH4) in three boreal lakes, during this annual event.

Cleaning process of abattoir wastewater with focus on bacterial pathogens

This study was conducted at the City Abattoir in Kampala, Uganda to evaluate the cleaning process, with focus on bacterial pathogens, in a pilot scale integrated bioprocess. This consisted of four steps: anaerobic sequencing batch reactors; aerobic/anoxic sequencing batch reactors; a high performance temperature controlled methanogenesis digester and a constructed wetland. The objective was to determine if this type of cleaning process could be used to clean wastewater from abattoirs in a satisfactory way. The indicator organisms for faecal contamination, Escherichia coli and Enterococcus spp. were used to investigate in what numbers bacteria could be found in the untreated wastewater and how much that was reduced in the different steps of the cleaning process. The water was analysed for Salmonella to see if human pathogens could be found and could survive the different steps of the treatment process.

Grundvattnets geokemi vid Gladhammars gruvfält, Västervik. Effekter av äldre tiders kobolt- och kopparbrytning

The municipality of Västervik, with support from Envipro Miljöteknik AB, is carrying out a main study of the minefields at Gladhammar. Mining of iron, copper and cobalt under different periods from the 16th century until the end of the 19th century has led to discharges of metals to the lakes situated downstream. The aim of the main study is to investigate the possibilities to reduce the environmental load on the surrounding ground and water caused by heavy metals from the mine. The present report is a part of the main study. The aim of the work is to investigate the geochemistry of the groundwater.

Analys av dricksvattenrening med metoderna Mikrobiologisk riskanalys, MRA och God desinfeksjonspraksis, GDP

Vatten är ett livsmedel som vi kommer i kontakt med dagligen. För att inte råka ut för sjuk-domar och infektioner renas dricksvattnet på vattenverken, främst för att reducera antalet patogener, d.v.s. sjukdomsframkallande mikroorganismer. Man brukar prata om tre grupper mikroorganismer i vattenrening; bakterier, virus och parasiter. Dessa grupper är vitt skilda i många avseenden och reduceras därför olika bra av olika reningssteg.

<- Föregående sida 41 Nästa sida ->