In the fluidized bed furnace at Rönnskärsverken, Skelleftehamn, sulphur-containing ore concentrates are roasted in order to remove about 50% of the sulphur in the incoming ore concentrate. This occurs in order to reach the goal of a matte containing 55% of copper in the following smelting process. At the same time as the ore concentrate is partially roasted pollutions as arsenic, antimony and bismuth are expelled. Earlier made thermodynamic calculations of equilibrium suggested that calcium and magnesium form stable compounds with arsenic and thereby inhibit expellation of arsenic in the fluidized bed furnace, an element that is undesired. The purpose of this thesis work was to gain knowledge of the mechanisms behind the formation of these stable arsenic compounds.

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.

How do you see on natural science within preschool? Does education and interest play a role for how the educationalist works with natural science? And is the children?s interest for natural science affected by the educationalist, what does the educationalist think himself? These questions have I under my teachers training and under deputyship in preschool asked myself and these questions lies to behalf for my investigation. I interviewed five educationalists on different preschools for my investigation.My investigation resulted in that I have been able to see a certain conjunction between how you work with natural science in preschool and the educationalist education or interest. What also plays a role is that you often associate natural science with knowledge of nature. The educationalist seems overall positive to natural science, but depending of a lack of knowledge it feels strange and difficult.

Burnt alun shale and lime is the residual product that was formed when alun shale was used as fuel to convert limestone to quick lime. The material contains arsenic, vanadium, molybdenum, cadmium, nickel, lead, and uranium among other elements. The aim of this paper is to examine the uptake of trace elements in vegetables grown on burnt alun shale and lime to determine whether or not the surrounding environment and humans are exposed to these elements by eating plant products. A cultivation trial was carried out where onion, carrot, and lettuce were grown on three mounds of burnt alun shale and lime in the Falköping area in Sweden. The treatments were burnt alun shale and lime mixed with peat, only burnt alun shale and lime, and a reference soil. The reference plots were natural soil mixed with peat adjacent to the mounds.

Sweden has a natural gas grid extending along the west coast, from Trelleborg to Stenungsund. There are also several smaller local networks where a planned natural gas pipeline from Skutskär to Hofors prompted the need for a comprehensive study. This study examines the linkages that exist in terms of technology and market of natural gas and biogas in Sweden. Sweden has set high targets for the future with ambition to become independent of coal and oil as energy sources. Since 1985, a part of the solution has been import of Danish natural gas.

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Trädgårdens hantverk och design22,5 hp, 2014.

Mechanical ventilation is the most common type ofventilation in newly constructed office buildings. Therehas been an interest to utilize natural ventilationinstead of mechanical ventilation among architects andHVAC consultants in recent years. This is due to thesize of mechanical ventilation systems, which arespace consuming. The mechanical ventilation system isalso complex and requires maintenance. Furthermore,the fan uses a considerable amount of energy.

The highly toxic man-made substance referred to as dioxin (polychlorinated dibenzo-para-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs)) causes severe health damages both to humans and other organisms, with lethality as its worst. Because of the toxicity several risk assessments has been performed on dioxins trying to determine at what concentration there are no risk of exposure. Resent years of research has discovered that these substances are not only anthropogenically but also producedin natural processes, like volcanoes and forest fires. To investigate if there is a need to take these naturally formed dioxins into account in the risk assessment processes, interviews with persons at relevant institutions in Sweden has been made. Analyses of existing risk assessment methods and political documents were also made to complete the picture.

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.

The purpose of this essay has been to compare different constitutions, and their outlook on citizenship, rights, obligations and natural duty. This has been done in the light of the political philosophy, in order to give the answer to four questions. These questions are: Which rights and obligations can be seen in the constitutions, and how can it be interpreted. Can there be signs of any political philosophy in the constitutions?  Are there any differences between the constitutions regarding citizenship, rights, obligations and natural duty? If so, what are the differences? Can the rights be seen in a further extent than the obligations in the constitutions?I have conducted a qualitative comparision study and analyzed the political philosophers and made a classification scheme of their views.

The municipality of Västervik, with support from Envipro Miljöteknik AB, is carrying out a main study of the minefields at Gladhammar. Mining of iron, copper and cobalt under different periods from the 16th century until the end of the 19th century has led to discharges of metals to the lakes situated downstream. The aim of the main study is to investigate the possibilities to reduce the environmental load on the surrounding ground and water caused by heavy metals from the mine. The present report is a part of the main study. The aim of the work is to investigate the geochemistry of the groundwater.

To turn the dairy heifers out on pasture is the most natural way for the cattle to get feed. At the same time it is cheap and if it is right treated a feed of high nutritive value. The problem today is to get dairy heifers to grow enough when they are grazing at natural pasture for the entire summer. Therefore, the opinions differ whether pasture is a resource or a problem. The increasing interest of pasture production is due to the fact that you can receive grants for preserving valuable natural assets and cultural landscape elements in the pasture land. A high grazing pressure is necessary to preserve an open landscape and a great variety of species. In the same time the heifers have to supply their nutritive needs in order to grow and be large enough to show heat and be pregnant in right time to calve with a sufficient body size and at an economically right age. This paper includes a literature review on natural pasture, pasture production, and growth of dairy heifers together with own interviews with dairy farmers about their point of view to the pasture husbandry on the farms, how they plan for pasture, look after natural pasture, treatment areas and take care of the calves and heifers. The results indicate that the time it takes and the demanded work are the biggest factors to how and why the farmers do as they do..

This thesis deals with how natural resource teachers in natural resource schools in Sweden work with entrepreneurial learning and entrepreneurship. It is important both for our Government and our agricultural department that entrepreneurship is present in our education. In government´s new reform 2011 for upper secondary schools entrepreneurship is the main theme, but it is not only entrepreneurship as a business company, it is also about entrepreneurship in schools like entrepreneurial capabilities in government´s writ. The purpose of this study is to examine how a number of teachers in natural resource schools are working with entrepreneurial learning and entrepreneurship. I have also asked how the teachers would like to work with these areas.The method I have chosen to use in order to perform this study is qualitative interviews with six natural resource teachers and a pilote interview.The teachers I interviewed are working to provide students with self-knowledge and teaches students to see possibilities and solve problems, which is required for us to create entrepreneurial students and entrepreneurship in education. This is also stressed in several of the literary sources I used..

This exam report has been developed in association with Strangbetong AB, Sweden.The natural gravel that is being used as fine aggregate for concrete production today is an ending natural recourse and the Swedish government has decided to strongly reduce the extraction from the year of 2020. The only reasonable replacement is aggregates from crushed rocks but this material has other properties than natural aggregates. The concrete manufacturers now have to learn how to use these new fine aggregates in a cost effective way in order to ensure the quality of their concrete production.In this project, crushed aggregates and combination of crushed and natural aggregates have been tested with existing formulas for fresh concrete. The two parameters yield stress and plastic viscosity have been measured which gives a good description of the workability of the fresh concrete. Different methods to make measurements on the dry fine aggregates, has also been tested, to find out if there is any correlations between these parameters and the parameters from the measurement on the fresh concrete..

This study shows how to plan a pond with an ecosystem which although it will have turtles living in it will not need to be cared. I will also demonstrate how this pond would be designed to work in the natural landscape on Mallorca. The background to the study is that I am interested to investigate how plants that we in Sweden are using as indoor plants are growing in their natural landscape and how to build a land-scape with them. The study highlights different cleaning-systems that can be used to clean a pond in a natural way. A comparison will be made between the conditions of an exterminated turtle-species which will live in this environment and a species that is easier to care for.