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498 Uppsatser om Heavy metal polluted - Sida 5 av 34

Industriella avloppsvatten i Chile : Identifiering av problem samt förslag på åtgärder

Chile and Santiago are struggling with heavy environmental problems as a consequence of urbanisation and industrialisation. In the Santiago region the air is seriously contaminated and most of the rivers are classified as heavily polluted.The aim of this thesis is to survey the industrial fluid waste situation in the Santiago region and to make suggestions on technological improvements or process changes. The purpose is also to study five different enterprises more closely and to give more detailed suggestions for improvement. Another purpose is to summarize relevant Chilean legislation.Information, provided by the supervisory authority, about the release of industrial wastewater to rivers has been analysed. Deep interviews have been made with authorities and consultants.

Kartering av markföroreningar inom Skutskärs Bruk samt utvärdering av spridningsrisker enligt Naturvårdsverkets MIFO fas 2

With the prospect of future construction on the Skutskär Pulp Mill property, Stora Enso Fine Paper has initiated an investigation of soil contaminants and a risk assessment of these contaminants. A soil and groundwater investigation has therefore been conducted on an open area of about 16 000 square meters, situated between the current wood room and digester house. To be able to integrate this study into an investigation for the whole industrial property, the study has been carried out as a phase 2 study according to the Swedish Environmental Protection Agency?s Methods of Inventories of Contaminated sites (MIFO).The site investigation has involved soil and groundwater sampling, together with the analysis of heavy metals and organic contaminants. The degree of hazard posed by the contaminants, the level of contamination, the potential for migration of the contaminants, as well as the degree to which protection of human health and the environment is required in the area, have been weighed together for an overall risk assessment of the area with regard to human health and the environment.The investigated area was built up by filling in the coastal waters.

Rening av metallhaltigt avloppsvatten : En teknisk/ekonomisk utvärdering av reningsmetoder för metallhaltigt avloppsvatten

This Master?s Thesis aims to investigate and assess the methods used to decrease the discharge ofmetals, primarily copper, from the water purification plant at Assa Industries plating factory inEskilstuna.Literature studies of the purification methods precipitation, ion exchange, evaporation, reverseosmosis and electrolysis has been done to appraise the adequacy of the technique. Thesetechniques are commonly used for purification of industrial waste water.Assa has four plating lines: the Trumline, the big Zinkline, the new Zinkline and the Decorativeline. The new Zinkline is the most modern of the four lines and purification is done byrecirculation over an ion exchange unit. The demand for fresh water is thereby heavily reduced.The Trumline, the big Zinkline and the Decorative line all use older techniques.

Empirisk studie av den radiella förspänningskraftens variation i klassiska skärskruvförband

In this study, the pre-tension force in an insert screw connection are examined in order to establish a greater understanding of the system and to facilitate the process of making new metal cutting tools. Certain especially significant design variables such as the offset, the length of the contact thread and the shank length above the threaded hole, are selected to be closely examined. A comparison of the influence on the pre-tension force between threaded holes made with a worn, versus new, threading tool is also involved in the experiment. The study is limited to handling the screw sizes M2,5 and M3,5. The results show that a regression model, with good approximation, can be fitted to the measured values.

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.

Ambulanssjuksköterskors upplevelser av sinarbetsmiljö i sitt dagliga arbete. : En kvalitativ intervjustudie

Abstract:Ambulance nurses have in their everyday work a varied work environment, the pace of work can quickly shift from being calm and structured to be a severe acute situation.Objective: The aim of the study was to describe how professional nurses in the ambulance operations experience their physical and mental work environment in daily practice.Method: A qualitative interview study with semi structured questions was used. The study group consisted of two women and three men, ages between 27?42 years. The study was carried out on an ambulance station in central Sweden. Based on collected data, a qualitativecontent analysis was performed that resulted in three categories.Results: The result showed that the ambulance nurses regarded that it was a lot of heavy lifting.

Modell för dimensionering av AGV-system inom tung industri

Interest in the implementation of AGV-systems (Automated Guided Vehicle) has in recent decades increased. The reason is that it allows companies to perform reliably and secure internal transport while reducing the need of personnel. It is one of todays most advanced and complex material handling system that can independently make their own decisions regarding flow paths and traffic control. An AGV-system consists of transport units carrying cargo from point A to point B, and communicates using a computer.The purpose of this study is to develop a model on how to proceed in order to design an AGV system in heavy industry. The model is tested by a case study of a company in the metal industry to determine if the model works and gives the correct result.

Så långt inuti, näst intill borta

Through wing pattern, posture and movement, a harmless moth of the family Brenthia imitates an eight-eyed jumping spider. When an octopus of the species Thaumoctopus mimicus sense danger it can alter its appearance to that of a venomous sea snake. They are both drawing attention to themselves. Nevertheless, and because of this, they are protected. The mechanism is called mimicry.

Bibliotekschefer och stress - En kvantitativ studie av arbetsrelaterade stressfaktorer i svenska folkbibliotek

This dissertation discusses head librarians in Swedish public libraries and the stress factors which affect them. The aim is to map out potential stress factors which head librarians come across in their day-to-day work. The purpose of the dissertation is to answer the following question: what stress factors affect library managers in Swedish public libraries? The dissertation was conducted through a literature study, informal interviews and a quantitative questionnaire. The results of the quantitative questionnaires show that the factor that produces the highest level of stress is having too many different tasks.

Ljus i butiksmiljö : Upplevelsen av ljus och exponering av produkter

This thesis examines how to improve the exhibition of products within retail for clothes and gift articles. The purpose is to investigate and test how light sources and different directions of light affect how the products are perceived regarding their exhibition. Our question formulations are:To what degree does the level of light in combination with the background of the interior design of a shop affect whether a product is perceived more or less attractive?What can we recommend to make the exhibition of products more attractive? From our observations shops nowadays have relatively high levels of light when they expose products on vertical areas. We have looked on the recommendation from ?Energimyndigheten? in order to see what they think is important when designing retail lightening.

Potentiellt förorenade områden i Ljungans avrinningsområde i Västernorrlands län : Finns det anledning att prioritera om arbetet med avseende på riskläget för översvämning, ras och skred?

Due to the climate change natural disasters expects to increase and in some areas the conditions for dissemination of hazardous pollutants from contaminated areas could be affected. Different inventories and mapping has been made to identify areas of risk for flood or avalanche around the country. At the same time inventory and treatment of potential polluted areas (MIFO objects) is progressing. In Ljungans run of area in Västernorrlands county is a exposed area due to the amount of clay and silt in the ground that are sensitive in the context avalanche. The area has also a lot of MIFO objects and risks of flood.This essay aims to investigate what data material that is available regarding MIFO objects, flood- and avalanche risks in Ljungans run of area in Västernorrlands county.

Ett re(el)lt hot? Om elprisets betydelse för investeringar inom basindustrin

The aim of this thesis is to investigate the correlation between the price of electric power and investments within the Swedish basic industry. Using regression analysis, the authors test for correlation between the electricity prices and the basic industry, defined as the pulp and paper industry, the mining industry, the steel and metal industry and the basic chemical industry. Moreover, five variables found in the literature on investment decisions are being used as a means of comparison. The results suggest that the electricity price affects the investment decisions within the basic chemical industry as well as the steel and metal industry. On a more abstract level, this thesis contributes to the understanding of one of the properties of the Swedish GDP..

Historiska emissioner av bly och arsenik till luft från Åfors Glasbruk och deras konsekvenser för miljön.

Åfors glasswork was a company which started in 1876 and closed in 2012 due to the bad economical situation in the company. After its closure, the glasswork left behind contaminated soil with different concentrations of heavy metals such as, arsenic from arsenic trioxide, a chemical used to remove bubbles during the melting of glass, and lead oxide, a chemical used in the production of crystal glass. Crystal glass?s production occurred under 1921-1971, but emissions of lead into the air from Åfors glasswork continued until 2011, because of the artist Bertil Valliens? artglas was made in Åfors glasswork from 1970?s and onwards.The aim of this study was to estimate how much lead (Pb) and arsenic (As) that were released by Åfors Glasswork into the atmosphere during the operational period of the glasswork in comparison with how much of lead and arsenic were purchased for the company. Added to the assistance of the data from National Archives the variations in the activities of Åfors glasswork could be shown.

Inventering och riskklassning av nedlagda deponier enligt Metod för Inventering av Förorenade Områden (MIFO), Uppsala kommun : Spridningsförutsättningar och transportprocesser i deponier samt ansvaret för förorenad mark

This master thesis encompasses an inventory and risk classification of four disused landfills within the municipality of Uppsala, Sweden. The model of the classification; ?Method of Surveying Contaminated Sites? is developed by the Environmental Protection Agency and can be used as a framework to investigate and describe the environmental damage and the level of risk for each object. The risk classification model has a rating from 1 to 4, where 1 represents a very high risk while 4 is a small risk. Risk class depends largely on the type of land use that exists on the object, and hence, various benchmarks must be taken into account.

Reglering av matarsystem vid höghastighetskapning

Today small metal parts are mass-produced as for example rollers in cylinder bearings. At high velocity cutting the metal is cut with a great force in a scissor-like device. Both precision and repeatability is important to be able to guarantee good quality, but from an economical point of view it is also important to keep a great manufacturing capacity. The part of the process that is most time consuming is when the metal bar, that is about to be cut, is fed to the right position. Therefore it is interesting to examine if the time used for positioning can be reduced.

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