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89 Uppsatser om Reverse osmosis - Sida 1 av 6
Rening av avloppsvatten med anaerob membranbioreaktor och omvänd osmos
This master's theses was carried out on assignment from Stockholm Vatten AB as a part of a project developing new waste water treatment techniques. The goal of the theisis has been to evaluate an anaerobic membrane bioreactor for treatment of waste water from Hammarby Sjöstad. The bioreactor has not been heated and the main interest has been to study the gas production, power consumption and the reduction of organic matter and nutrients.The system has been completed with a Reverse osmosis unit and a total of four batch runs have been made with good results. The use of Reverse osmosis allows nutrient in the waste water to be reintroduced into circulation as the Reverse osmosis concentrate can be used as crop nutrient.The membrane unit is of VSEP ("Vibratory Shear Enhanced Processing") type and an extensive membrane test has been conducted. This so called L-test helped determine the most suitable type of membrane for the system to allow a higher ±ux and thus lower power consumption.
Återvinning av näringsämnen från hushållsspillvatten med omvänd osmos
Hammarby Sjöstad is a new district in Stockholm with high environmental standard. Stockholm Water Company evaluates a local wastewater treatment plant with cutting edge technology. The first step is an experimental treatment plant (Sjöstadsverket) with four parallel lines of treatment, each with a capacity to treat wastewater from 150 persons. Within the membrane technology subproject the possibility of using Reverse osmosis (usually called RO) to regain nutrients is examined.Reverse osmosis separates the incoming water in a clean permeate and a concentrate that, as the name indicates, is a more concentrated version of the incoming water. Using this method in wastewater treatment, a solution high in nutrients can be obtained without the use of chemical precipitation agent and with no production of sludge.
Produktion av dricksvatten och förnybar el i Bläsinge fiskehamn
The fishing port of Bläsinge is located on the east coast of Öland, Sweden?s second largest island. Today the port has a limited supply of freshwater. The economic association of the fishing port wants to expand their business, so that they will also include tourist services. To do this the harbor will need a more independant source of freshwater, with a higher quality than the present well.
Utvärdering av anaerob behandling av hushållsspillvatten och tekniker för efterbehandling
The continuous process of urbanization results in demands on research and development for ecological and sustainable city development. Because of this, the current systems for wastewater treatment may have to be improved. In order to evaluate new technologies for municipal wastewater treatment, a development project has been initiated for the new district Hammarby Sjöstad in Stockholm. The project is lead by the company Stockholm Water. High environmental standards have been put up for the district, as it must be twice as good as an ordinary new district.
Reverse engineering : En processkartläggning på reverse engineering
Alstom Power Sweden AB in Norrköping isexpanding their business in the presentsituation and has implemented aprocedure for reverse engineering as apart of this work. Reverse engineeringat Alstom is an extensive procedurethat is calculated to be performedunder very time demanding conditions.This thesis is a continued exertion ofthe implementation process in order toidentify and describe the mostimportant process steps in purpose to beable to manage and improve theprocess.This thesis was written with twoprimary objectives. The first was todescribe and map out the procedure torecreate technical data of a turbineblade, based on a validation of thereverse engineering process that hasbeen performed at Alstom in Norrköping.The second purpose was to describe thekey factors to achieve successful usageof reverse engineering that have beennoticed in the literature study.The work is based on a literature studyon the subject reverse engineeringwhich produced the theoreticalknowledge of the method to reproducetechnical data to a product. Theliterature study has also led to adescription of reverse engineering froma legal perspective to clarify how farit is allowed to apply the methodaccording to the patent laws. With theliterature study as support and furtherhelp and guidance from individualswithin the reverse engineering unit atAlstom, a complete picture andunderstanding of the process has beenproduced and documented..
Analys av framtidens system för hantering av avloppsvatten och matavfall i Eskilstuna
Wastewater treatment is increasingly controlled by the Swedish environmental quality objectives, adopted by the Swedish parliament. There is a need for a sewage system that can fulfill stringent requirements concerning the environment, recycling and resource use and hygiene. Additional environmental aspects in recent years are the impact of climate change, new knowledge about the effects of pharmaceuticals in water, the need for improved wastewater treatment and increased recycling of nutrients to agriculture. This report has, from a future scenario of the year 2050, analyzed seven different systems for wastewater treatment and treatment of compostable biowaste from households in Eskilstuna. A future scenario was chosen based on that within a forty year period new challenges may arise which can result in higher demands on sewage treatment than those we see today. Another reason why the future scenario was established is that changes in wastewater treatment systems are slow to establish. The analysis is mainly focused on the economical aspects but environmental aspects such as emissions to receiving waters and potential recycling of plant nutrients has also been evaluated briefly.
Reverse Engineering : En jämförelse mellan företag och forskare
Användning av mjukvaruverktyg när reverse engineering utförs är ett måste för att få ett användbart resultat enligt Hainaut (2002). Kudrass m fl (1997) visar på brister som kan uppstå när mjukvaruverktyg används. Gemensamt för de forskare som har studerats i detta arbete är att de hävdar att företag saknar kunskap för att utföra reverse engineering med mjukvaruverktyg. Har forskarna rätt i att det saknas kunskap eller har företagen mer kunskap än vad forskarna tror? Då dessa forskare har en klar koppling till tillverkning av mjukvaruverktyg så är eventuellt inte deras påstående opartiska och därför är det intressant att se om deras påstående stämmer med verkligheten.
Omvänd aktiesplit : överlevnad eller kosmetik
The shareholder is supposed to be indifferent if one share costs 100 SEK, or 10 shares cost 10 SEK each. In an efficient market, shares should be valued directly to new expectations as a result of the announcement of the reverse split. We investigate whether abnormal returns incur surrounding reverse split and if owner structure change.One reason for the reverse share split is that most companies have plans to imple-ment other company?s specific events in order to survive rather than to change the price range to a more attractive level. We found a negative return in the ex-day at 8,1 per cent.
Patenträttsliga aspekter på reverse engineering: ett klargörande om under vilka förutsättningar reverse engineering inom tillverkningsindustrin är tillåtet enligt patenträtten
Denna uppsats har som syfte att klargöra hur långt det är tillåtet att med reverse engineering experimentera med en patentskyddad uppfinning innan patentintrång föreligger. Främst förs en diskussion om hur långt det är tillåtet att experimenteramed en patentskyddad uppfinning, utifrån patentlagens experimentundantag, utan att kränka ensamrätten som patentet ger. För att svara på denna fråga börjar diskussionen ur ett svenskt perspektiv i den svenska patentlagen, med ett instick ilagen om skydd för företagshemligheter. Diskussionen förs sedan ut i Europa för att se hur bedömningen av reverse engineering och experimentundantaget gjorts där och till sist vänds blicken mot USA. Bedömningen som görs är att reverse engineering ges ganska fria händer så länge målet för processen är att finna ny kunskap utöver den kunskap som finns inbäddat i patentet.
Naturlig förekomst av arsenik och avskiljning av arsenik från grundvatten : test av olika filtertekniker avsedda för enskilda brunnar
During the last few years the presence of high arsenic (As) concentrations in ground water has been of major concern both internationally and in Sweden. Much evidence has been reported about toxic effects caused by arsenic. The carcinogenic effects and the possibility to measure the toxic impacts at low concentrations made the World Health Organisation (WHO) to reduce the guideline value from 50 to 10 ?g l-1 in 1993. In Sweden the corresponding reduction was implemented in 2003.
Several surveys in Sweden have shown that high arsenic concentrations may occur in ground water.
Miljö- och hälsoskyddskontorets tillsynsarbete - ur verksamhetsövarens perspektiv
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.
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.
Näsnarens framtid i ett näringsstatusperspektiv
Eutrophication has been a problem in aquatic systems for a long time. It is well known that the key nutrient to control the eutrophication process is phosphorus. Lately, it has been possible to reverse the process and recover lakes from eutrophication.During a long time Lake Näsnaren in Katrineholms kommun, Södermanland, has been exposed of a large amount of phosphorus from the city's wastewater. The lake has a great value as a habitat of rare species but also a high recreation value for people living in Katrineholm and Södermanland. Lake Näsnaren is situated in a Natura 2000 area.
Kapitalkostnaden på Stockholmsbörsen: En studie av marknadens implicita riskpremie i hög- och lågkonjunktur, samt hur den implicita kapitalkostnaden korrelerar med kapitalkostnaden enligt CAPM
This thesis explores some issues regarding estimations of the cost of capital on the Stockholm Stock Exchange through reverse engineering of the Residual Income Valuation model and through usage of the Capital Asset Pricing Model. Previous studies are in conflict of whether the risk premium changes considerably over time or not. Furthermore, the risk premium estimated by CAPM tends to be fairly stable. In this study, reverse engineering of the cost of capital implied by analysts? forecasts shows a significant difference in the risk premium over time.
Vattenkvalitet : Underlag för förbättring av vattenkvalitet
Dricksvattnet ombord på Sjöfartshögskolans fartyg Calmare Nyckel har vid tidigare provtagning visat på undermålig kvalitet. Orsaken till detta har inte undersökts innan. I detta arbete undersöks och identifieras orsaken och ett underlag för förbättring av vattenkvaliteten har tagits fram. Underlaget omfattas också av en arbetsbeskrivning för ombyggnation av färskvattensystemet och ett underlag för installation av en färskvattenproducerande anläggning. För att kontrollera vattenkvaliteten ombord genomfördes vattenprover och en undersökning av färskvattensystemet med endoskop.