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2382 Uppsatser om Reserve water source - Sida 13 av 159

Utvärdering av vattenrening och identifiering avförluster m a p energi vid Bravikens pappersmaskin 53

This Master degree project has been performed at the Braviken paper mill on papermachine 53 (PM53) which produces newsprint paper. The current economic situationhas contributed to declining demand for newsprint, which means it is extra important tobe competitive by high energy efficiency. Particularly as energy prices are expected torise when the economic growth returns.One way to increase energy efficiency is by reducing the water use in paper and pulpmills and consequently save energy through reduced heating of water. The thesis's maintask is to evaluate whether a water purification plant (microflotation plant) forpurification of process water in PM 53 is profitable. The microflotation plant enablesreuse of warm process water instead of losing the energy to receiving waters.

När kritiska elever är målet. Att undervisa i källkritik på gymnasiet

This essay examines teaching in source criticism in upper secondary school history education. Two questions are to be answered: 1. What are the conditions like for teaching source criticism? 2. What opportunities for further development in teaching source criticism are there? In order to set a standard for what knowledge and skills in source criticism the students need, I design a four step model for good source criticism based on the historical science.

Informationssökning i elektroniska informationskällor Valmöjligheternas vånda

The purpose of this thesis is to examine which factors influence librarians selection of electronic information sources, and to investigate whether librarians use of search strategies and search tactics changes depending on which information source they use. The electronic information sources are: online databases, Online Public Access Catalogues OPAC, World Wide Web, and CD-ROM databases. The theoretical framework is based on step 3 Select a source and step 4 Formulate a Query in Marchioninis information seeking model. The search strategies are divided into two categories: analytical and browsing strategies. In order to supplement the theoretical framework with empirical facts, 8 librarians were interviewed.

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.

Analys av blått och grönt vattenfotavtryck för nötkött från ICA:s sortiment

ICA vill utveckla sitt miljöarbete i vattenfrågor. Denna rapport syftar till att öka medvetenheten hos ICA om verksamhetens miljöpåverkan genom att analysera vattenfotavtrycket ? vanligen kallat Water Footprint ? för ett livsmedel. Vattenfotavtryck är ett verktyg inom miljösystemanalys som används för att kartlägga sambandet mellan produktion och konsumtion av produkter och vattenanvändning. Studien visade att vattenfotavtrycken är ungefär 14 500 liter/kg och 16 500 liter/kg för svensk respektive irländsk nötfärs.

En j?mf?rande studie mellan tv? v?treng?ringsmetoder p? papper

Amongst the published literature researching wet cleaning of paper there is a limited amount of studies conducted researching the method simmering water treatment. There are even less studies conducted on how simmering water affects the paper being treated when used as a cleaning method. Despite the limited research, there are literary reviews describing the method and suggesting it as an alternative for conservation of paper with iron-gall ink. The following study will therefore be examining, the somewhat unusual method, simmering water treatment, and comparing it to one of the more common wet cleaning methods: immersion washing. This is done to compare how the different temperatures of the water affect the paper. The types of paper used in this study consists of three dyed and four undyed papers. All of the papers are new, apart from one sample originating from 1847.

Driftoptimering av torkmaskin : Driftoptimering av torkmaskin 3 vid Billerudkorsnäs Karlsborg 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.

Konstruktion av en fotobioreaktor för odling av alger : ett småskaligt försök

The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.

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.

Fornstora dagar och framtidens risker : Historiemedvetande och historiebruk kopplat till Sverigedemokraternas principprogram från 2005 och 2011

The subject for this thesis is to analyze the Swedish political the Sweden Democrats (Sverigedemokraterna) through the use of history theories. The purpose is to examine the following two questions:1. what types of history consciousness is present in the source material2. the use of history (historiebruk) shown in the source materialThe source material has consisted two official party publications, Sverigedemokraternas principprogram from 2005 and 2011.The main theoretical frameworks for the analysis has consisted of the typology for use of history as presented by professor Klas-Göran Karlsson together with selected theories connected to history consciousness, not the least the model presented by Bernard Eric Jensen.The result of the analysis shows frequent examples where the use of history and history consciousness is present in the rhetoric used in the source material. By tracing the use back to the theories selected Sverigedemokraterna?s deployment of use of history and history consciousness is interpreted and discussed..

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.

Konceptstudie av Waste Heat Recovery System på Tunga Fordon

In today?s fast growing and closely connected society, a reliable and energy efficient transportation system is more than ever desirable. Nowadays the significant part of the transportation sector?s energy demand is supplied by fossil fuels.Improving energy efficiency in combustion engines will result in reduction of fuel consumption and CO2 emissions. A modern internal combustion engine has an efficiency of 30-45 %, where the most energy loss occurs as result of heat losses in the exhaust and cooling systems.

Dagvatten i Märsta : förslag till anläggning för ekologisk hantering samt metodöversikt

Stormwater in urban areas has been treated as a problem for a long time. The large proportion of impermeable surfaces inhibits the water from infiltrating in the ground to the same extent that it does in nature. This causes intensive surface flow during rain, which in turn causes inconveniences such as decreased accessability, floods and increased risk of desease spreading. Drainage through pipes is the traditional and usually functional metod for storm water disposal. That is as long as water flows are moderate. But precipitation varies naturally in amount and intensity and additional impermeable surfaces make some pipes insufficient for heavy or lasting precipitation.

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