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3605 Uppsatser om Water treatment plant - Sida 14 av 241
Beskrivning av systemfunktioner i kärnkraftverk med hjälp av objektorienterat modelleringsverktyg
In order to facilitate design and maintenance of such a large and complex site as a nuclear power plant, all system functions must be described in a stringent way. In the past, these descriptions consisted of text documents and logical diagrams, but today there are an increasing number of object-oriented programs available on the market which might be used for this purpose. This Master Thesis has made a closer study of one of these programs named Rational Rose. The principal of the program is to facilitate software design and development, not to create models of plants. However, using the program the same way as developing software, specifying actors then gradually extend the model with use cases, use cases diagrams etc, the same methods can be used when modelling plants.
Undersökning av deponerat ferrokromstoft : Utvärdering av ny behandlingsmetod
The production of ferrochromium alloys at Vargön Alloys AB contributes to formation of unwanted ferrochromium dust, which contains toxic Cr(VI). The dust is since summer 2005 treated with an iron-sulphate solution to reduce Cr(VI) to the non-toxic Cr(III). A year later the treatment technique was improved and disposal occurs in cells on the landfill. The cells can be up to 300 m3 and the edges can be made out of fro example concrete. Tests are conducted on the treated dust when it is disposed.
Vermicompost for reduction of vegetable waste - and a possible means to produce fish feed in aquaponic systems?
Aquaponics is a food production system consisting of a consecutive cultivation of plants and aquatic animals, fish or shellfish, in recirculating water. The plants feed on the nutritious effluents from the fish tank and bacteria converts ammonia from the fish tank into nitrate that is absorbed by the plants. The plants receive nutrition and the fish gain purified water.
The environmental impact of the production of fish meal and fish oil used in conventional fish feed includes a large consumption of fossil fuels with subsequent carbon dioxide emission.
The aquaponic system can be made environmentally sustainable and self-supporting if supplemented with a vermicompost/vermiculture for the production of worm protein as a fish feed.
Vegetable waste from the hydroponic part of the system can be reused as worm feed in the compost and the protein rich worms can be harvested, dried and grinded and brought back to the aquaculture as fish feed.
As a first step in this direction, I have investigated the effect of recycling of vegetable waste in vermicomposts on the growth and number of earthworms (this was evaluated after harvesting).
The hypotheses were that earthworms can be cultivated in the vegetable waste and that by adding manure to the vermicompost it is possible to obtain a nutrient content adequate to support a continuous worm harvest, in other words create a vermiculture.
Eisenia fetida and Dendrobaena veneta were grown in 20 L bins containing peat mixed with either poultry or cattle manure. The proportions were 70% peat and 30 % manure. Discarded plant parts from lettuce cultivation was added to the vermicomposts (35 g per week) and water was supplied
with 0.8 L per week.
OTEC för Tarawa
Ocean Thermal Energy Conversion, OTEC, a technology using the temperature difference between cold deep seawater and warm surface water, can extract the work in the form of electricity. OTEC gives also synergies of drinkable fresh water. The temperature difference has an impact on the efficiency of the technology, which means that the feasibility of OTEC is geographically limited. The project intends to explore the possibility of replacing the atoll Tarawa?s present electricity generation with an OTEC plant and to explore synergies. In the present situation all of Tarawa?s electricity is generated by fossil fuels.
Drainfill
Ocean Thermal Energy Conversion, OTEC, a technology using the temperature difference between cold deep seawater and warm surface water, can extract the work in the form of electricity. OTEC gives also synergies of drinkable fresh water. The temperature difference has an impact on the efficiency of the technology, which means that the feasibility of OTEC is geographically limited. The project intends to explore the possibility of replacing the atoll Tarawa?s present electricity generation with an OTEC plant and to explore synergies. In the present situation all of Tarawa?s electricity is generated by fossil fuels.
Nya tillämpningar för utandningstest kopplade till Kibions diagnostikinstrument IRIS®
The aim of my thesis is to obtain knowledge of textile wastewater and textile sludge from an environmental perspective, which can be used as a basis for the ?Sweden Textile Water Initiative? guidelines for a sustainable sludge management. In my study I have mainly focused on textile dyes, salts and metals and their routes during wastewater treatment.This paper is partly a literature review, which I began by identifying the pollutants discharged from each textile process. Then I studied wastewater and sludge quality, environmental aspects, possible treatment and recycling methods. I have also tried to find existing type of guidelines in order to make comparisons.
"Fallbacks" - betydelsen av vandringstid för Atlantlax (Salmo salar L.) som faller nedströms vandringshinder
In Lake Vänern, Sweden, there is an endemic population of Atlantic salmon (Salmo salar L.) that lives its entire life in fresh water. The salmon is hindered from migrating to its natural spawning sites in the northern part of the River Klarälven by nine hydro-electric power plants. None of the hydro-electric power plants have fishways so that salmon migrating upstream or downstream may pass. In the current situation, the upward migrating salmon are caught in a fish trap at the most downstream located power plant in Forshaga. From there, the salmon are driven in a truck, past eight power plants and released a few kilometers upstream of the eighth power plant at Edsforsen.
Hållbar växtnäringshantering i Stockholms län : En aktörsanalys
Plant nutrients are important for all life on earth and are also important as fertiliser infood production all over the world. Because of this, plant nutrients are of great valuebut they also bring problems. As an example, the loss of nitrogen and phosphorusfrom agriculture and urban society's sewage systems contributes to some of today?smajor problems in water environment. Another problem associated with plantnutrients is that finite recourses are used in the production of mineral fertilizers.
Validering av metoder för analys av Cu, Fe och Na i processvatten med AAS-grafitugn
Södra Cell Mörrum is one of the five paper pulp plants that are included in Södra Cell, and the paper pulp that is produced here is not only sold to Swedish paper mills. Most of the paper pulp is exported to different countries in Europe. In the manufacturing process the plant needs different kind of process water and there are guideline values for how much copper, iron and sodium this water is allowed to contain. Analyzes of this water is in the current situation done with an atomic absorption spectrometric instrument (AAS-instrument) with a flame. Measurements done with flame-AAS of samples that have concentrations near the guideline values for copper, iron and sodium, are not reliable. The reason for not being reliable is that the quantitation limits of these metals are higher than the limit values.
EU:s medborgarinitiativ : En framkomlig väg för att minska det demokratisk underskottet?
The European Union is struggling to maintain democracy and tries to increase the participation among the citizens in Europe. The European Citizens? Initiative, ECI, is a platform established by the European Commission to allow citizens to propose new legislation. ?Water and sanitation are a human right! Water is a public good, not a commodity!? is the first ECI that has met the requirements.
Mobbning : En studie om fyra skolors förebyggande arbete mot mobbning
A school should be a safe place for all students. The existence of discrimination, harassment and offensive behavior should according to Swedish school law not exist in the school environment. Since the year 2006, when a law on equal treatment was passed, all the schools in Sweden must have a treatment plan that is revised annually to prevent discrimination, harassment and abusive treatment.In this master thesis, I will examine the equal treatment plan between four different elementary schools in Nynäshamn.The purpose of this paper is to examine how the equal treatment plan exposes the bullying and the types of problems and solutions addressed in the elementary schools equal treatment plans. Based on the purpose, I have formulated two questions:How do the elementary schools in Nynäshamn municipality describe bullying in the equal treatment plan?What kinds of problems and solutions are addressed in the equal treatment plan evaluations?This thesis is based on text analysis and content analysis on the schools equal treatment plans.The study is based on the theories from a norm critical perspective.The conclusion of the study is that all four schools treatment plan see abusive behavior as something serious and preventive.
Före och efter Trappan-modellen : En pilotstudie om psykiska, emotionella och beteendemässiga förändringar hos barn som upplevt pappas våld mot mamma
The Trappan Model is one of the most implemented treatment programs for children who have experienced domestic violence. This study undertakes a wider evaluation of the model through a pilot study. The approach is both quantitive and qualitative. Theory as well as the Strengths and Difficulties Questionnaire have been used to fulfil the aim. The design is pre-post.
Små vatten- och avloppssystem : Möjligheter till inskränkning av verksamhtesområden
This study is focused on small scale water and wastewater handling in Sweden. The study is divided into two major parts; the first describes common methods for water- and wastewater handling and the second part is a case study on three small and expensive systems in Gällivare municipality, in the north of Sweden. In the case study, abilitys for the local government to hand over unwanted systems to the water users is investigated and found to be a plausible solution to cut costs for two out of the three studied systems. In the third case, water and wastewater systems is not recommended to be handed over but other ways of cutting costs are suggested..
Uppgradering av biogas i systemperspektiv med avseende på miljöpåverkan och kostnader
Swedish biogas is currently produced mainly by anaerobic digestion of sewage sludgeat sewage treatment plants, landfills and anaerobic digestion of household or industrialwaste. Also cattle ma-nure from farms can be used to produce biogas. Upgradingbiogas represents an increase in methane concentration from about 65 % to about 97%. In addition, particles and contaminants must be sepa-rated from the upgradedbiogas. There are various methods for upgrading and this report compares sixdifferent methods with respect to environment and economy: water scrubber,Biosling, cryo technology, chemical absorption, Pressure Swing Adsorption (PSA) andmembrane separation.According to the used ORWARE model, chemical adsorption with amine has the leastenvironmen-tal impact (methane emissions) and the lowest costs.
Lactobacillus reuteri som probiotisk terapi mot bakteriell vaginit hos avelsråttor :
Lactobacillus reuteri has been used as probiotics in piglet and chicken feedings as
well as in different diary products for humans. In this EEF-work I have shown that
L. reuteri can be an alternative for treatment of vaginitis in laboratory rats used for
breeding. In a breeding stock with 3000 animals some animals had a vaginal
infection with ??haemolytic streptococci group G.