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4841 Uppsatser om Water model - Sida 5 av 323

Grundvattenmodellering i Badelundaåsen

Over an extended period of time there have been plans to establish a shared facility in Lennheden to extract groundwater from the Badelunda esker to provide drinking water for the cities of Borlänge and Falun. The city of Falun is dissatisfied with the quality of its drinking water and the city of Borlänge is concerned about the risk of contamination of its existing groundwater supply at its current location. To provide a basis for a decision on this issue, the company Midvatten AB has been commissioned to perform hydrogeological investigations in the area of Lennheden.The purpose of this thesis is to design a functional groundWater model of the area between Lennheden, place of planned extraction, and Övre Tjärna, place of existing extraction, to get a better understanding of the groundwater situation in the area. A groundWater model enables simulations of different scenarios in risk assessment and contaminant transport. The aim of the thesis is that the model can be used as an aid in Midvatten?s investigations in Lennheden and that it also can be used in future projects in the area.The model has been made in Processing Modflow 5.3 and encompasses an area of 19,5 × 11 km along the Badelunda esker and the river Dalälven between Djurmo and Frostbrunnsdalen.

Rimbo våtmark : en förstudie på förväntad kväveavskiljning och lämplig växtlighet

This study was made as a part of a feasibility study on a polishing wetland at Rimbo wastewater plant (wwp) in Norrtälje municipality. The wwp had to decrease the nitrogen discharge to reach the limit 15 mg tot-N/l. The nitrogen in the outlet was mainly in the form of nitrate, hence the wetland mainly ought to support denitrification. The proposed area for the wetland was situated right next to the wwp and was already in the municipalitys posession. One aim of this study was to examine what spieces of plants needed to achieve highest possible denitrification.

Avskiljning av uran från dricksvatten med reaktiva filter :

Water is our most important provision and its quality is above all dependent on the geological conditions in the area from where it is extracted. Due to geological properties there are certain areas with an elevated risk of high uranium levels in the ground water, which in turn constitutes a risk for human health. Consumption of water that contains a high concentration of uranium implies a health risk due to the chemical characteristics of uranium. Livsmedelsverket (The National Food Administration) and Socialstyrelsen (The National Board of Health and Welfare) therefore recommend that precautionary measures should be taken when the uranium concentration in ground water exceeds 15 micrograms per litre. In particular, drinking water collected from wells in areas with uranium-rich bedrock may have a harmfully high level of uranium. One of the wells of the Ärla water purification plant, located near Eskilstuna, Sweden, contains water that exceeds the guideline of 15 micrograms per litre. One interesting technique for removing uranium from drinking water is adsorption to reactive filter materials.

Öppen dagvattenhantering i urbana miljöer :

Storm water causes a number of problems in our country, particularly in city environment with its surfaces of non-absorbing ground materials. At heavy rain falls there are floods due to lack of capacity in the drain system when meeting heavy water masses over a short time. When the drain system is overloaded huge water masses reach the recipient untreated and there causing disturbances in the aquatic ecosystem. Due to emissions from mainly traffic, industries and other human activities the storm water is polluted. Earlier the problem used to be solved technically, by increasing the capacity of the tubes and by construction of reservoirs to delay the floods peaks.

Milk production in dairy cows and goats : a case study in the Nyando district inSouth-Western Kenya

Water is an essential factor for both people and animals, and access to water is therefore of great importance. The water access also largely determines the availability of food for people and feed for animals. The aim of this study was to survey the affect of water access on milk production from dairy animals. The study included nineteen farm visits that were made in the Nyando district in Kenya between February and Mars 2011. Farm visits included interviews with questions about for example number of dairy animals, milk production, water access, feed and water routines.

Ett flervariabelt feldetekteringssystem för övervakning av bärlagertemperaturen i vattenkraftturbiner

The purpose of this thesis work was to develop an automatic fault detection system for surveillance of bearing temperature in hydropower turbines. The parameters used except the bearing temperature were cooling water temperature and cooling water flow. A simple static model based on data sampled every minute was developed to estimate the bearing temperature. Then a detector for detection of change in bearing temperature based on the CUSUM-algorithm was designed. Since the amount of data was very small the developed model was too uncertain to be used in a working system.The designed fault detection system showed to work well for the available data.

Kadmium i skånska vattendrag : en metodstudie i föroreningsmodellering

Modelling of pollutants is commonly used in research and at departments working with environmental issues. The need to use large amounts of data when modelling creates the opportunity for more generalised models with lower data demands. Aggregating functions into coarser elements is a sort of generalisation of actual features in nature.A development of a method and a modelling tool called ?KadmiumKalkylatorn? has been performed to model cadmium pollution in rivers in Skåne, Sweden. The water runoff has been multiplied with cadmium standard concentrations based on membership in landuse classes.

Development of Liquid Cooling for PCs

In recent years, existing solutions for cooling personal computer CPUs have been supplemented by a new product category, factory sealed water cooling loops. These systems, consisting of a water block with an integrated pump, a fan and a radiator, perform well compared to the air cooling solutions but are less effective than larger, custom-built water cooling systems.This project aims to explore the most important aspects of a factory sealed system and to identify possible cost-effective enhancements of the performance.The most significant differences between the different groups of water cooling loops are the block design and the pumping power. The performance of both categories is also largely dependent on the fan power, but increasing fan power has a large negative impact on the noise level.Both radiator size and fan model choice appear, in tests, to be relatively unimportant, presuming that the noise level is kept constant. The position and direction of the fan, however, has significant impact on both the temperature and the sound level.Water blocks can be designed in several different ways, both regarding the heatsink design and the flow direction. In simulation, flow with the inlet centered above the heatsink result in considerably lower pressure drop and slightly higher temperatures than flow through the block, for heatsinks with fin arrays.Creating a competitive product in this product segment certainly seems possible, as there are performance-increasing changes to be made that seemingly has little impact on the production cost.

Tjänligt vatten i kranen - Membranteknik gör det möjligt : En utredning av pilotförsök i Glemmingebro

Nanofiltration is a proper way of preparation of drinking water. The process has a lot in common with reverse osmosis where a semipermeable membrane is used to separate a pure water flow from the remaining water. A pilot plant was used to ensure that nanofiltration is a suitable technology for a specific waterworks station in Glemmingebro, Ystad. The purpose was also to find out if a pH-adjustment is needed for feed water in a possible full scale plant.  In this case nanofiltration is used mainly to remove sulphate and calcium since the raw water contains concentrations of these substances which exceed the limits for potable water. It is important to receive a high recovery (RC), otherwise the deliviery of water won?t be high enough.

Wallenius waters AOT luftrenare

This bachelors thesis was made forWallenius Water AB to develop a basisfor an Airpurifier prototype. Wallenius Water isone of the world's leading environmentaltechnology companies engaged inchemical-free water treatment based onUV-radiation. The thesis aim was toproduce a basis for a prototype that canbe used in three applications:Standalone, RAS systems and ventilationsystems. The work includes anintroductory description of the theorybehind AOP technology based on aliterature review on the subject. Asurvey of products currently on themarket and a product specification hasbeen used as the basis for thepreparation of a number of concepts inthis report.

Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering

Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined.

Vem för de törstigas talan? : En studie av debatten kring vattensektorn

1.1 billion people are today living without sustainable access to improved water. The debate over the water sector has been dominated by the discussion over whether public or private actors are the most competent to manage it. In this paper the arguments pro and contra the two positions are presented to try to overview the debate and to try to find new ways to approach the question of the people living without clean water. By examining possible alternatives towards the discussion of public and private actors, it might result in some new approaches on how to move closer towards a solution. One alternative is local, small- scale projects which focus on the situation of the targetgroup in most need.

Riskbaserat provtagningsprogram för mikroorganismer i Gäddviks vattentäkt

Risk-based sampling program of microorganisms in the water source in northern SwedenAfter several disease outbreaks caused by parasites in the drinking water during the last years, it is more essential than ever to insure that the water supply companies have enough barriers to counteract the presence of microorganisms in the outgoing water. It is also discussed whether climate changes such as increased precipitation can have a connection to the increased cases of parasites in water sources. The water source at Gäddvik is Luleå municipality?s largest and provides drinking water to 64 500 of Luleå?s 74 000 inhabitants. The investigation of microorganisms in the water source, especially in the Lule River has not been as prioritized as the sampling of chemical parameters.

Lakningsförsök med furubarksflis : en utredning om utsläpp av fenolföreningar samt metallsorption

The filters used today to purify water are often expensive and the need to find new filter materials is substantial. Studies of pine bark have shown that this is a material that may be used as an alternative to conventional filter materials, such as activated carbon. However, the study of pine bark has shown that a leakage of phenolic compounds may occur when using the material for water purification. Therefore, the purpose of this report is to investigate the release of phenols from pine bark, in order to evaluate the use of pine bark as a filter material. Another assignment is to investigate the amount of metals adsorbed by the filter material.

Hur mycket "mjölk" ska det vara i mjölken, och hur styr vi det?

In most countries, the dairy industry focuses on the volume of milk produced instead of its composition. This results in a high content of water and a lower proportion of fat and protein. A high proportion of water is not desirable when processing the milk into various dairy products like cheese, cream and milk powder. High water content also increases the costs for transport and storage, and also an unnecessary, albeit marginal, strains on the world?s water reservoir.

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