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1616 Uppsatser om Surface water - Sida 1 av 108
Metoder att förhindra nedisning av vindkraftverksblad
ABSTRACTMany wind turbines have problems with icing and there is still no effective method to de-ice without stoppage of production and power loss. Here I therefore consider other methods than those available today, and particularly, I consider how these methods could be applied to wind turbines of the company Oxel. A surface where the water droplets do not attach might be the basis for a useful method. If no water attaches, no ice could form. To accomplish this a hydrophobic surface is nessesary, for example wax.
Finngruvan - Uppföljning av vattenkvalitet, analys avavrinning och recipienter i området efter gruvdrift
This thesis raises the problem with acid mine drainage around the closed mine Finngruvan.The purpose of the investigation was to compare metal content in Surface water in the areaand its catchments between year 2010 and 2003, also to make calculation of specific runoffand metal load, furthermore determine the recipients in the area. Surface water samplingwhere preformed at the same place as 2003 and also at a few other places of interest. Adigital elevation file were used in GIS to calculate the area of the watersheds in the region,observations in the field where also made. The collected data were used to make comparisons,calculations and conclusions. The result showed that the Surface water 2010 had somewhatlower metal concentrations.
Vätning på mikroskala
Individual cellulose ?bers were studied to identify the transport and absorbtion phenomena as well as the in?uence of drying. A Chalmers University of Technologydeveloped method within ESEM (Enviromental Scanning Electron Microscope) has been used in this study. The results from the laborations gave the following conclu-sions: The transport of water occurs in ?bers in the ?ber wall surface and the lumen.
Energieffektivisering i ett reningsverk för skogsindustriellt avloppsvatten genom förfällning av extraktivämnen
Pulp- and papermills expend vast amounts of water in order to produce pulp, paper and cardboard. Hence, they alsocreate vast amounts of waste water which has to be cleaned before it can be released into the receiving body of water. Insuch a wastewater treatment plant, tremendous amounts of energy are expended by the aeration in the biologicalcleaning process. This aeration is necessary to supply the microorganisms that shall decompose organic material withoxygen, which they need for their metabolism. The transfer of oxygen from the gas phase to the liquid phase isprimarily inhibited by surface-active substances in the waste water like resin acids or fatty acids.
Hållbar vattenförsörjning i områden med vattenbrist : Sustainable water supply solutions for areas affected by water shortage
In some coastal areas in Sweden water shortage sometimes appears because the withdrawal of groundwater is greater than the groundwater recharge. It creates a situation where the available groundwater is insufficient to support residents and businesses with drinking water. The high withdrawal of groundwater also creates a risk for saltwater intrusion to drinking water wells. The problem most commonly occurs during the summer when the groundwater recharge is low, but the population is high, due to tourism and summer residents.The purpose of this study was to investigate how local water supply in areas affected by water shortage can be solved as sustainable as possible. The work was divided into three parts where the first part comprised of a literature review on water systems in which four different options were investigated: artificial groundwater recharge, rainwater harvesting, desalination and water reuse.
Sänkta sjöars inverkan på ytvatten i Västerbottens kustland : Samband mellan sänkningsnivåer och vattenkemi i sjöar på sulfidrika sedimentjordar
Lake lowering in sulphide-rich areas is currently a major environmental impact for Surface water. This study focuses on whether there is a relationship between a gradient of lake lowering and Surface water impacts in areas of sulphide-rich sediments, in order to better understand their contribution of heavy metals and sulfuric acid. Also, is it a reasonable method to use the reduced lake area in order to quantify the gradient? The survey was conducted by collecting water samples from reference lakes and lowered lakes from south to north in coastal areas within the county of Västerbotten. Water samples were then analyzed for TOC, pH, conductivity, anions, base cations, alkalinity, acidity, sulfate, Al, Cd, Fe, Mn, Cu, Zn and Pb.
Stump treatment with the root rot antagonist phlebiopsis gigantea : - sensitivity of P. gigantea spores to high pressure stress; - reduced water consumption for stump treatment
Stump treatment today requires large quantities of clean water mixed with the protective product Rotstop, to fully cover the stump surface. In order to reduce the
water consumption without reducing the coverage of the stump surface, the pressure in the stump treatment device can be increased. Therefore, the Phlebiopsis gigantea
(Fr.) Jül. suspension used as a biological control agent to prevent Heterobasidion annosum (Fr.) Bref. infection was pressure-tested.
Vattenskydd och krisberedskap hos allmän dricksvattenproduktion : Skydd av täkter, tillgång till reservvattentäkter och andra nödvattenlösningar hos svenska vattenproducenter
The objective of this report was to analyse and compare vulnerability and preparation in Swedish municipal drinking water production, in case the commonly used water sources were inoperative. Methods used were a questionnaire and a less extensive study of regulations for water protection areas. The questionnaire was answered by 41 Swedish municipalities. A handful of them were companies co-owned by a few municipalities. Only one out of four municipalities had source protection areas to all their water sources and for many sources the protection was not satisfactory.
Hyllie vattenpark : ett gestaltningsförslag
This project is focusing on a future park that will surround Hyllie water
tower in the outskirts of Malmö. The water tower will be located in the
central part of the new building area Hyllievång. The park will function
as a town park with a special focus on water. The water council of the
municipality, Va-verket, has for the last 7 years built up and been in
charge for a pedagogical programme in the water tower, were schoolchildren
come to learn about the cycle of water and how we use water
in our daily life. In the park they want to build a new part that gives
experience of water, as a compliment to the information in the tower.
What will that park look like, and what shall it be constructed of?
How do you bring water to the surface in a park? How can landscape
architecture work to enhance the presence of water and make people
more interested in water issues? In the search to find the answers to all
my questions I have meet with people, read books and visited different
places.
Computer Modelling of the Influence of Surface Topography on Water Repellency and a Study on Hydrophobic Paper Surfaces with Partly Controlled Roughness
A computer model based on minimization of the free energy, capable to predict contact angles and spreading transitions between Wenzel and Cassie mode for drops placed on surfaces with different topography were implemented in matlab. Simulations were compared with experiments documented in the literature. These showed that reported transitions between Cassie and Wenzel mode can be explained by minimization of the free energy. In this report, a study on the possibility of constructing water repellent paper surfaces with a combination of treatment with octadecyltrichlorosilane and topography changes, is included..
Växters förmåga att ackumulera metaller : Vass, bredkaveldun och gäddnate i Bergviks dagvattendamm
AbstractSurface-water includes different kinds of pollutants from traffic and roads. To prevent these pollutants to reach nearby lakes one can construct surface-water ponds on locations with heavy traffic. At Bergviks shopping centre in Karlstad, two ponds, one smaller and one bigger has been constructed in order to decrease the pollutant pressure from the receiving waters of Kattfjorden. Several heavy metals are essential for plants and animals in low concentration but when they occur in higher concentrations, they become toxic to the organism. The larger pond at Bergviks shopping centre has a sedimentation function so the heavy metals sink to the bottom thereby not releasing directly in to Kattfjorden.
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.
Kommunikation mellan två medium
The aim of this project is to find a concept solution for a wireless transmitting system, installed to transmit data from a hydrophone of the ocean floor down by a wave power generator to the office on shore. The project is a literature review in which previous observations and tests are analyzed and put together to find a solution. The result was a comprehensive solution that includes an acoustic modem to transfer captured information from the bottom to the surface, wirelessly through the water. The information is then sent fron the surface on radio waves through the GSM network to the office on land. Between under and over water there are components to convert information between acoustic waves and radio waves, but also various types of modulation, such as amplitude and frequency modulation is required..
Anva?ndning av markfuktighetskartor fo?r sta?ndortsanpassad plantering
Digital depth-to-water maps can be produced from a digital elevation model (DEM). Then GIS- based algorithms are used to calculate water flows and the depth-to-water index classes dry, fresh, moist and wet. The purpose of this study was to investigate the possibility to use depth- to-water maps for site adapted planting.The results showed that use of depth-to-water maps for site adapted planting, roughly halved the proportion of improperly planted surfaces from an average of 9 % to 4 %. The variation in the values of proper surface decreased and the result became more even.. In addition, more pine than spruce was incorrectly planted.
Igensättning av långsamfilter i Östby vattenverk i Kramfors : studie av påverkande faktorer
Östby waterworks in the community of Kramfors has since 2003 had problems of fast clogging of the slow sand filters. As the clogging appears more often, they must be cleaned more frequently which has made the drinking water preparation difficult. Wintertime it has sometimes been impossible to clean the filters which has led to their closing and this has influenced the water quality negatively.The waterworks is a Surface waterworks which takes its raw water from the lake Sjöbysjön. The water is flocculated and filtered in a contact filter with the flocculent EKOFLOCK 91. Thereafter it is alkalinized before it reaches the outdoors placed slow sand filters.