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1660 Uppsatser om Water purification plants - Sida 19 av 111

Bestämning av vattenytor med hjälp av Nätverks-RTK och totalstation : Inmätning av Karlbergsån i Grums kommun

This report is presenting an approach that can be used to measure water surfaces in difficult conditions caused by dense vegetation and lack of nearby known points. The objective was to make a contribution to necessary measures for adaptation against floods in Grums Municipality along the stream Karlbergsån, which may occur when persistent rain raises the level of the stream. Along the river there are low-lying areas prone to flooding. According to Grums Municipality, the stream may widen where the water level differences are large, to create a better flow path and to counteract flooding. Grums Municipality was also interested in survey stormwater discharges which may affect the water level in the stream.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in the event of rainfall. An increased level of radioactivity in the plants may occur due to interception and retention of the radionuclides. If the content of the plants is above the threshold limit value, entire yields may have to be destroyed. In order to prevent contamination or decrease the content countermeasures can be taken. The impact of the biomass, leaf area index (LAI) and growth stage of the plant on the interception and retention is important to know in order to decide which countermeasures to use. Weather may also be an important factor. In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley and spring oil-seed rape was studied.

Källor i Lagga, en uppländsk slättbygd : Geografisk och geologisk påverkan påkällvattens egenskaper

For centuries, springs have played a significant role in our society as water supplies, reasons for where to settle down, and in folklore. There are different reasons why and where a spring forms, e.g. in what kind of soil it has its outflow. Geographic and geochemical surroundings have an influence on spring-water quality.For this project some of the springs in the Lagga perish, Knivsta municipality, Sweden, were selected for a closer study. Water samples were collected from springs for analysis.

Markavvattningsföretagens geografi och konsekvenser i Trosaåns avrinningsområde

Agricultural drainage is widely used to manage the amount of water in the ground in order to improve conditions for cultivation. However the effects of drainage companies on water regimes are considerable leading to runoff changes such as altered stream flows, peak flows and water levels. In a greater extent this could imply an increased risk for floods along affected watercourses. This study analyzes the extension of agricultural drainage within the drainage basin of Trosaån in Sweden by ArcGIS mapping. In a statistical analysis, historical variation in streamflow in relation to mean precipitation and mean temperature are investigated for the study area.

Projektledares synpunkter på projektprocessen

A clean and affordable energy source for cooking is deficient in developing countries. People rely on fuels that contribute to environmental, social and health problems.Biogas is an alternative energy source and an increased investment in small-scale biogas production can in several developing countries be found. Several projects have started to use the technology in developing countries because of the benefits with biogas. Some cases in the establishment of biogas plants have succeeded and some have not. The study is a literature review supplemented by two field studies.

Förskolebarns tankar om vattnets kretslopp i naturen och i samhället. : skiljer sig pojkars och flickors svar åt?

AbstractThe work will give the picture of what four- and five-year-olds know about the water cycle in nature and in the society. Is there any difference depending on whether a boy or a girl is answering? The work will as well try to describe a picture of how a pre-school could plan their work on a sustainable society, science, and increased gender equality. To answer these questions the information has been received from interviews with children and by studying pre-school?s local plan.    Earlier research on the area of water shows that it is important before working with a new topic to find out what knowledge the children already have, so that the process could be as worthwhile as possible.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in theevent of rainfall. An increased level of radioactivity in the plants may occur due tointerception and retention of the radionuclides. If the content of the plants is above thethreshold limit value, entire yields may have to be destroyed. In order to preventcontamination or decrease the content countermeasures can be taken. The impact of thebiomass, leaf area index (LAI) and growth stage of the plant on the interception andretention is important to know in order to decide which countermeasures to use.Weather may also be an important factor.In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley andspring oil-seed rape was studied.

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.

Framtidens avloppsvattenreningsverk ? en modern energiproducent : En fallstudie av Himmerfja?rdsverket

In a sustainable society the use of renewable energy and recycling of materials is of high importance. Wastewater treatment plants use large amounts of energy in the processing of wastewater. This study seeks to evaluate wastewater as an energy resource and to examine treatment plants potential to become sustainable energy producers. The study is based upon the internal processes of Himmerfja?rdsverket.

Stadsodling : möjligheter och begränsningar

Urban farming can be viewed in several contexts. The first part of this work brings up the beneficial effects of farming on our physical and mental health, knowledge as well as on social life in cities. The introduction of gardening in schools can contribute to an increased awareness on both agricultural practices and importance as well as ecological processes. It can also be used in teaching of other subjects. Farming can also contribute to improving the household economy, and the economy on a municipal or national level.

Konstruktion av pipelinebro i Charagua, Bolivia

Guazuigua is a small village in Bolivia, which has had too small water resources, especially for irrigation. A project started after some studies were made, to create a canal to provide the village with water from a nearby town. To make the canal work it had to cross a dried out river. There have been several attempts to cross these dried out rivers, but with poor results. The purpose of the report is to provide a solution for this problem.

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.

Översvämningsmodellering av ett dagvattensystem

Storm water management has become a more important matter as urban areas are expanding and natural areas are being exploited. As nature landscapes are being converted into hard surface areas storm water flow is affected both in terms of velocity and size. A flow increase can easily result in a flooding if the dimensions of the pipeline system are inadequate. Considering predicted upcoming climate changes, flooding?s may become more common in urban areas in the future.

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.

Feng shui i trädgården :

Our environment affect us, not least gardens. By practising the ancient Chinese art feng shui, one could find tools how to create harmony and balance in gardens. By paying attention to different energies working with colours, shapes and materials one can create a nice garden with good feng shui. The philosophy, however, includes much more than what plants or what hard materials to choose in the garden. It describes different energies, the movement of energies, which we can learn to live in harmony with.

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