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371 Uppsatser om Metal contaminated soils - Sida 8 av 25
Tillförsel av använda fosforfilter påverkar inte tillväxten eller fosforupptaget hos korn
The eutrophication of inshore seas, lakes and watercourses is mainly due to leaching of nitrogen and phosphorus (P) from agriculture. Many efforts are made to reduce the lea-kage of phosphorus in Sweden and the Baltic Sea countries. Phosphorus is also a finite resource and the mining of good quality raw material gets more and more difficult. Se-dimentation dams in combination with filters is one relatively new method to separate P from run-off and drainage water from agricultural land. This study was a part of an IVL Swedish Environmental Research Institute?s project which tests the capacity and func-tion for separation of phosphorus in four phosphorus filters.
Separeringsmodul
In cooperation with the Gislaved company Lerocon AB [1], a separation module wasdesigned as a further supplement to the Module System. The aim of theprojectimplementation was that the separation module could be flexible enough to feed themetal pieces, screws, nuts and other items with large variations of size, appearance andmaterial composition. The module should also be cost effective to manufacture.A separation module is a design which is ment to streamline the work in industries withautomation of the lineoperations. The module feeds the details such as screws, nuts, washersand pieces of metal in a continuous flow in which traps separate the details from each other.Traps may vary depending on the purpose and of the details that are fed. Perhaps it isimportant for the user that the detail-orientation is right after the separation module, whichmeans that all the pieces witch aren´t are fed back in return.For companies and industries in lineoperations that can be made more efficient withautomation, are production flow an important watchword.
Mineraliska material som reaktiva filter för avskiljning av tungmetaller från dagvatten
Highly polluted urban storm water from e.g. highways can contain large amounts of heavy metals that may cause harm if they are discharged into recipients. To remove the heavy metals a possible low-cost method that does not require much maintenance, could be the use of reactive filters with filter materials consisting of industrial residues or other cheap mineral based materials. Dissolved metal ions are removed by reactive filters through the processes of ions binding to active sites on the surface of the filter materials, or by formation of insoluble precipitates.The ability of CaO-treated granulated blast-furnace slag, iron oxide coated sand, olivine and nepheline to remove seven heavy metals (Cr, Cd, Cu, Ni, Zn, Pb and Hg) from urban storm water was studied. Initially batch experiments were performed where the effect of pH, dissolved organic carbon (DOC) and dissolved ions on the adsorption efficiency was studied.
Undersökning av svetsegenskaper för svetsning med rörtråd kontra homogen tråd
Welding is a common method for joining of metal or plastic construction parts. This report describes several different weld methods in general terms. The report focuses on the GMAW method, specifically MAG welding.A case study has also been performed for the company Wenmec. The task received from the company was to compare the mechanical properties of joints welded with the tube electrode called Nittetsu SM-3A and joints welded with the homogenous electrode called ESAB Aristorod 12.63. Both types of weld joint were welded with the MAG method with an Argon based shielding gas with 18% CO2.
Gimo bruksområde - inventering och riskklassning enligt MIFO fas 1 :
This master thesis encompasses an inventory of the older industrial community of Gimo.
Investigations of the contamination situation for each industrial area were done. A risk
classification according to the Swedish Environmental Protection Agency?s ?Method of
Surveying Contaminated Sites?, phase one, followed. The risk classification was done on
areas of Iron Work, a rockwool industry and a landfill.
Gimo have had iron manufacturing from 1615 until 1945. Gimo have had two blast-furnaces
and two smithies periodically.
Geokemin inom osorterade cirklar : Analys av tungmetallers distribution inom jordprofiler tagna från Abiskoområdet, nordvästra Sverige
The Arctic region appears as a pristine remote environment, yet there is increasing evidence that it is greatly impacted by pollution such as lead (Pb) and mercury (Hg). In this environment deposition of Hg has increased threefold since the last industrial revolution. In this study five cryosolic soil profiles within non-sorted circles (NSC) in the Abisko region, northwest of Sweden, has been analyzed to improve our understanding regarding how pollutants are distributed within such type of soil. The soil samples have been analyzed with the use of X-ray fluorescence analysis (XRF), for the measurements of the total concentrations of e.g. lead (Pb) and zirconium (Zr).
Stubblyftningens initiala effekt på emissioner av växthusgaser från en granmark i Småland :
In order to reduce greenhouse gas emissions from human activities fossil fuels will have to be replaced with renewable energy alternatives, such as bioenergy. Sweden has a great potential to produce bioenergy derived from forest products and there is currently a great interest within Sweden in using stumps for bioenergy production. However, the environmental consequences of the method need to be investigated before stump removal can be performed on a large scale. Swedish forest soils contain large carbon pools and a different land use may change conditions so that soils that presently act as sinks of carbon could potentially turn into sources of carbon release instead.
This study investigates the initial effects of stump harvesting on the emissions of three greenhouse gases, carbon dioxide, methane and nitrous oxide. The emissions were measured from the soil surface in a Norway spruce forest located in the southern part of Sweden.
3D-visualisering i markprojekteringsprocessen
The thesis has been made for NCC Teknik in Gothenburg. The NCC Corporation is one of the largest leading companies in Scandinavia within the construction industry. NCC is active throughout the whole construction process, where one part is to carry out soil investigations prior the construction of various buildings, for example residential buildings. NCC Technology wants to visualize the samples taken at the construction sites in 3D for clients, authorities and also internally to show in a simple and understandable way how contamination is spread out in the soil.The thesis includes the area of Limhamns läge in Malmö, previously an industrial area. The area has previously included a concrete factory and the contamination from that factory has lingered in the soil.
Löslighet och metylering av kvicksilver i en förorenad sjö (Ala-Lombolo) i Kiruna kommun :
Transformation of inorganic mercury (Hg) to methyl mercury (MeHg) is a biotic process that is proposed to be conducted primarily by sulphate reducing bacteria (SRB). The formation of MeHg is of great interest because it is the mercury species that biomagnifies to the greatest extent in the aquatic food webs; about 90 % of all Hg in fish is MeHg. Our understanding of factors involved in the production of MeHg is very important for making a reliable risk assessment. The purposes of this study were to investigate the different factors that control the solubility of Hg and the production of MeHg in a contaminated lake sediment.
The lake Ala-Lombolo, Kiruna municipality, is well-known to be contaminated by mercury from different sources. Sediment cores were sampled at three different locations (N, SW and SE) in the lake and divided in three different layers; 0-5, 5-10 and 10-15 cm.
Bäddodling av matpotatis :
This study investigated potato growing in beds as an alternative to conventional ridges.It was based on results from field trials on bed-grown potatoes carried out by Halland Rural Economy and Agricultural Society in 2007, studies of literature and interviews with farmers with experience of bed growing of potatoes.
Due to their shallow root system, potatoes are one of the most drought-sensitive crops. Potatoes are often grown on sandy soils with poor water-holding capacity. Factors such as total yield, tuber size distribution and quality defects are negatively affected when water becomes insufficient. Wide beds have a more flat top which leads to more uniform water infiltration. Further on, beds have lower soil surface area due to its shape, and therefore, retain water more efficient.
In the field trials, which were carried out at the Stjärnarp Estate near Halmstad, potatoes were grown in beds alongside a conventional ridge-grown crop.
Järnets introduktion i Skandinavien : -I ett arkeologiskt perspektiv
The views on and the knowledge of the introduction of iron to Scandinavia have change by the history of archaeology. The results and discussions are put in the context of time and how that time is reflected in their work and texts. This limits that scholars put up to orientate themselves conceal the complex reality. The limits are changing all the time and is dependent of time and person..
Parametriserad 3D-modell av cyklon : Parametrisering av en 3D-modell av ett cyklonfilter i SolidWorks för snabb framtagning av nya konstruktioner till Outotec Skellefteå
This bachelor thesis project has been executed at Outotec Sweden AB in Skellefteå. Outotecs main business focus is selling mineral and metal processing technologies. A rest product from the metal process is particle-polluted gas and cyclone designs are today the most commonly used abatement device for particle control. A cyclone provides a simple design with high efficiency particle percolation by using air streams.The purpose of this work is to reduce the time it takes create new cyclone designs in Outotecs projects. An extensive construction work is needed for every new cyclone order due to new designs.
Erfarenheter av utedrift med köttdjur i Sverige och Kanada :
Beef cattle wintering outdoors should be provided a shelter, e.g. a type of barn or corresponding. This type of production requires appropriate soil types and secured animal welfare. For example, a clean and dry resting place needs to be provided to the animals. To receive an exemption for buildings the farmer has to have something equivalent that provides an adequate shelter.
Carbon sequestration in the pastoral area of Chepareria, western Kenya : a comparison between open-grazing, fenced pastures and maize cultivations
Carbon sequestration through restoration of degraded pastoral soils is an advocated way of mitigating global warming, and simultaneously alleviating poverty. An often proposed rehabilitation strategy is fencing of pastures, a method that was introduced to the farmers of Chepareria by the Vi-Agroforestry organization in 1987. The landscape of Chepareria changed from eroded, over-grazed grasslands, to a mixture of open-grazed commons, pastoral enclosures and cultivations. The aim of this study was to investigate (1) if the soil organic carbon (SOC) is higher inside the enclosures than on the open-grazed commons, (2) if SOC is affected by duration of fencing and (3) what effect cultivation of pastures has on the SOC. Estimations of vegetation cover and deep profile (100cm) soil sampling was performed on six clusters containing; (1) open-grazing (OG) (2) 1-5 years of fencing (FENCED(1)), (3) 7-10 years of fencing (FENCED(2)), (4) 15-23 years of fencing (FENCED(3)), (5) maize from OG (A(OG)), (6) maize from fenced pasture (A(FENCED)).
Sustainable phosphorus management of horse paddocks at Julmyra
Horse keeping is gaining an increasing interest in Sweden. During 2004 to 2010 the number of horses increased
with 10 - 20 %, and was estimated to be 362 700 in 2010. Julmyra Horse Center (JHC), situated in Heby municipality,
is a gated community for people sharing a large interest for horses and a vision of a sustainable horse
management has been formulated. This study evaluates how the horse keeping of today at JHC, and how an
expansion of the horse keeping may affect the risk of enhanced phosphorus load to the nearby lake system
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