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1845 Uppsatser om Water exchange - Sida 9 av 123

Stadsnära hav : en intervju/enkät om upplevelsen

The environment that surrounds us affects us all. Research has shown that we feel physically and emotionally best in natural environments with greenery or water elements. Urban environments are likely to be more stressing then natural environments. How we experience specific elements, as water, of an environment is not as much investigated. There is a need of further knowledge for us to fully understand the interplay between our senses and the environment. Human beings have always been depending on water and the search for it has characterized our deeds and doings through out evolution.

Energieffektivisering av aerbo reningsprocess : Tillsats av biprodukter i skogsindustriellt avloppsvatten

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

DEHP - från mjukgörare till hormonstörande

Eutrophication is a major problem in the Baltic Sea, as a result of increased loading of nitrogen and phosphorus. In the coastal parts of Östergötland the soil largely consists of clay and contains high levels of phosphorus bound to clay particles. Erosion of the soil in agricultural areas makes the water turbid and transports phosphorus to the Baltic Sea. The aim of this project was to examine the relationship between phosphorus and turbidity in the coastal streams of Östergötland. The aim was also to evaluate the possibility to use turbidity as a surrogate measure for phosphorus.

Inverkan av olika joner och jonconcentrationer på porstorleksfördelningen i trämassa-fibrer

The basic ingredient of paper is the individual wood fibers. The property of the fibers depends on a variety of factors e.g., method of pulp production and processing. The final sheet quality depends in part on how the fibers interface between each other and therefore factors that affect the fiber size are of interest.The flexibility of the fibers depends in part on the pore water i.e., the fiber swelling. The sheet becomes less flexible at low water content which gives a loss in strength. Thus it becomes desirable to increase the water uptake.The experimental investigation described in this report consists of exposing the wood fibers to different ions and ionic strength and then measure the pore size by thermoporosimetry where a DSC (Differential Scanning Calorimeter) is used.

Den positiva hälsovågen : En kvantitativ studie om hälsofrämjande arbete

The construction of buildings and paved surfaces changes the natural water balance.Precipitation generates surface runoff and storm water instead of infiltrating into the soil.Storm water has come to be considered as a major source of pollution in lakes and streams inthe vicinity of urban areas. Reduction of pollutants in storm water is a key action in order toprotect sensitive recipients and maintain high water quality. Storm water is traditionallytransported by storm sewers to the nearest recipient. In recent years the approach to stormwater management has changed; storm water should primarily be disposed of on site, throughlocal disposal of storm water, LOD. LOD is created by a combination of the function ofseveral smaller local facilities and the general sewer system.

Nitrat i grundvattnet : Modellanalys av vattenflöde till Hörviks vattentäkt

A well, situated on Listerlandet in the western part of Blekinge in Sweden, has a very high content of nitrate. Water with a too high content of nitrate is hazardous to human health, in particular to small children. The area surrounding the well is mostly drained agricultural land with some larger farms for chicken and mink. The well takes its water from the bedrock and is deeper than most other wells affected by nitrate. The bedrock in the area is dominated by limestone with a relatively high flow of water.This thesis was performed in order to find the source of the nitrate.

Lillån : Statusbedömning enligt EU:s ramdirektiv för vatten

In Sweden, the County Administration board is responsible for improving the water quality in lakes and watercourses according to the European Union Water Framework Directive. In Västmanland county, where river Lillån is situated, the County Administration of Västmanland have the main responsibility for the aquatic environment in that area. The knowledge about the different watercourses in the chatchment of river Lillån is today limited. The aim with this study was to evaluate the ecological quality of River Lillån based on water chemistry analyses and benthic fauna investigations. The aim was also for the benthic fauna to compere different samplingsites and sampling methods with each other in order to see how the species composition changes in the river, and to see the advantages and disadvantages with different sampling tecniques.

Förbättring av den svenska kiselalgsmetoden-hantering av sedimentering

Benthic diatoms are used in Sweden for monitoring water quality in run-ning water; the method is also frequently used in other countries in Europe. One of the problems of the diatom method is the need for sedimentation of the fresh sample, to be able to decant the over standing water and add alco-hol as a preservations solution. To my knowledge, no results have been published about how long the settling time must be to ensure that the ben-thic diatoms really have settled down to avoid a loss of the diatoms when decanting the over standing water. The aim of my investigation was to improve the Swedish method where the benthic diatoms are used for water quality monitoring. I wanted to find out the appropriate time necessary to wait until all diatoms have settled down before decanting the over standing water. First, fresh benthic diatom samples were taken in the river Fyrisån and the lake Mälaren on different days. After arriving in the laboratory, I waited three different times (30 min, 60 and 180 min) for the diatoms to settle.

Koffeins påverkan på osmolariteten i tårfilmen

Purpose: The purpose of this study was to investigate if there was a difference in the tear film?s osmolarity before and after drinking coffee. 'Method: All subjects in this study were asked to fill in a questionnaire to diagnose factors in their subjective symptoms, the questionnaire TERTC-DEQ. The subjects with a total graduated points of over 17 were not allowed to participate in the further measurements. In the study there was a total amount of 38 subjects, were 5 participated twice for both measurements, coffee and water.

Att ta vara på solens fulla uppvärmningskapacitet

The purpose of this bachelor´s report is to expand the knowledge about heat supply of a small house in Malmö. The heat supply will be provided from solar panels in combination to two accumulator tanks which will storage the up heated water and a pellet boiler.The technique used here is warmth storage in water over seasons, which will provide the total need of heating for the house. Accumulator tanks in combination to solar panels gets more and more common in Sweden but this far it´s unusual to use it for storage over seasons. This report will highlight many of the difficulties associated whit heat storage and give information about a system's possible design and function.The design of this system is decided early on. An accumulator tank is placed 2 meters down in the earth on the backside of the house.

Utvärdering av möjligheten att tillvarata energi ur processvatten : En undersökning gjort vid Olofsfors AB på uppdrag av UMIA AB.

The company Olofsfors AB manufactures drive belts for forest machinery, known as ECO-Tracks, and abrasion-resistant steel and cutting edges for graders, excavators and tractors, known as Bruxite and SharqEdges. Manufacturing these products requires the steel to be heated and molded, then submerged in water and hardened. The water used in the hardening of steel is pumped to the process from pits below the floor and then pumped back to the pit after it?s been used. Since the temperature of this water rises after being used to harden the steel the temperature of the pumping pit needs to be adjusted to maintain its setpoint of 21°C.

Lokalt omhändertagande av dagvatten i Västerås - Möjligheter till ökad användning i befintliga innerstadsområden : Local disposal of storm water i Västerås - possibilities for increased use in downtown areas

The construction of buildings and paved surfaces changes the natural water balance.Precipitation generates surface runoff and storm water instead of infiltrating into the soil.Storm water has come to be considered as a major source of pollution in lakes and streams inthe vicinity of urban areas. Reduction of pollutants in storm water is a key action in order toprotect sensitive recipients and maintain high water quality. Storm water is traditionallytransported by storm sewers to the nearest recipient. In recent years the approach to stormwater management has changed; storm water should primarily be disposed of on site, throughlocal disposal of storm water, LOD. LOD is created by a combination of the function ofseveral smaller local facilities and the general sewer system.

Vattnets väg genom en romersk stad. -Från vattenkastellet till mottagaren.

The purpose of this paper is to make an analysis of the urban Roman water system. I have chosen to work with the system as a general field, not as a case study of a single town. In my opinion such a study would not give a proper and fair view of the subject. Therefore, this paper will discuss the different parts of the system, each one for itself and name examples wherever possible, to give a wide survey of the reality of the Roman water supply system. The aim is to give the reader a clear picture of different solutions used in the time of the early Roman Empire and a good understanding of the subject..

Dagvattnets föroreningar som potentiellt hot för en god ekologisk och kemisk status i ytvattnet : En kartläggning av Vallentuna tätorts dagvattenhantering utifrån dess tillsynsbehov

The EU's Water Framework Directive aims to a long-term and sustainable use of our water resources and wants to ensure good water quality in Europe's water bodies. Discharge of polluted stormwater into receiving waters can be a threat to their ecological and chemical status. Municipalities are responsible for supervision of the environmental quality standards (EQS) and therefore need to gain knowledge of current stormwater management, the expected level of pollution emissions and possible appropriate purification steps to ensure that the goal of good water quality is achieved.This master thesis aims to provide this knowledge in the example case of Vallentunas urban area and wants to prepare future oversight so that it can be assessed how much the discharge of polluted stormwater into the local receiving water is a threat to its status. With the help of maps, aerial photographs, site observations and individual discussions those areas are mapped where appearance of moderate to highly polluted stormwater could be suspected. The degree of pollution at the discharge points is determined based on land use upstream and uses standard values according to the administrators assistance "Tillsyn av dagvatten" (MSL 2014).The study identifies 100 areas in need of supervision regarding their stormwater management.

Turbinkretspump system - Kraftvärmeverket i Borås

The Rya power plant in Borås produces district heating, district cooling and electricity. The plant is owned by Borås Energi och Miljö AB and is run by Dalkia Facility Management AB.In order to get the best heat exchange from the district hot water a pair of twin pumps and a turbine circuit pump are used as return pumps. Turbine circuit pumps are used to increase the pressure through the heat exchangers at the power plant. The pumps are in use when the flow is over 2 000 m3 h-1 and during the summer when re-cooling is used to improve the effectivens of the heat boilers.Since the pumps, that are parallel connected, rotating at a fixed rate per minute, the pressure is regulated with regulating valves. This report shows that during the 4,300 hours that the pumps where in use, energy corresponding to 590 MWh was wasted.

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