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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Icke förnyelsebara risker : Svenska gruvbolags riskhantering av en eventuell framtida metallbrist

Hervestad, Caroline January 2008 (has links)
A major issue that has been a subject for quite some time is whether there will be a scarcity of metals in the bedrock in the future and whether or not we might end up with a problem similar to that of the big oil crisis in the mid-seventies. Following the oil crisis many oil companies started up with risk management to control future risks. This work presents how Swedish mining companies work with risk management to handle risks that might come up in the future due to metal scarceness. How Swedish mining companies look at the possible metal scarceness and if they use risk management in their decision-making process is studied. By doing interviews with Swedish owned mining companies it was found that the mining companies did not see the future metal scarcity as a risk, even though 2/3 of the companies acknowledged the scarceness to be a reality. Nor did they use risk management for that specific issue. However, risk management in other issues related to metal scarcity was found, and by using different financial risk analyses the companies could look at probabilities and consequences of different risks. With these findings in mind the suggestion for mining companies is not to put effort, money and resources into metal scarcity risk management since it cannot be controlled, but instead put effort, money and resources into finding substitutes for metals and recycling the metals already in rotation.
12

Metal release and mobility in an arctic lake due to artificial drainage : Effects of mining and sulfide oxidation

Svahn, Joacim January 2012 (has links)
The aim of this report was to investigate the potential effects of sulfide oxidation in sediments of an arctic lake, N Luossajärvi, induced by lowered water level. Lake water, potentially contaminated by metals, was pumped into a mine tailings impoundment. The water quality in the receiving water was evaluated to see if the drainage have had an effect on the water quality. Six sediment profiles were sampled. Each profile were divided into 5 cm sections and analyzed for major elements and trace metals. Water chemistry were analyzed at six sites. As, Ni and Cu had high concentrations within undrained sediments, where As levels were classified as highly contaminated (> 27 mg kg-1 dw). Trace metals had strong statistical correlation to each other indicating a common source. The PCA analyzes performed suggests that trace metals are controlled by a common factor and drained sediments showed two additional factors controlling the variance of metals. Water chemistry had overall good status, but As, Cd, Ni and Cu exceeded natural background values. Historical data on the other hand showed no statistical difference from measured values. No effects on water quality could therefore be seen after draining of the lake, proposing high precipitation of metals within the tailing or that metals is still prevailing in the drained sediments. Metal mobility were seen within the drained sediments, where only As and Cd were presumed connected to chemical weathering and where erosion and soil properties seems to be responsible for most metal mobility.
13

Mineraljakten – en uppsats om minerallagens förenlighet med egendomsskyddet. / Hunting for minerals – a thesis on the individual’s right to peaceful enjoyment of property versus the interest of mining.

Jantzen, Oscar January 2020 (has links)
No description available.
14

Gruvrätten vid Stora Kopparberget 1641-1682 : en undersökning över rannsakade brott och utdömda straff

Falk, Johan January 2007 (has links)
The purpose of this essay is to examine and explain how the Swedish mining court of Stora Kopparberget (the Great Copper Mountain) implemented its judicial legislation between 1641-1682. Questions are asked about which counts of indictments the court tried, which sentences they handed out, in what quantities and how these results looks in comparison with other contemporary courts. The index cards of the court judicial protocols are the primary source of information. The methods are those of quantity- and comparative analysis.The results show that theft of copper ore was the most common crime ransacked by the court. Other common crimes were (in order): sin of omission, transgression of work directions, fights, slander and disdain, trade of stolen ore, failing appearance in court etc.Fines were by far the most common sentence followed by shorter imprisonments, gauntlets, loss of right to mine possession, twig beating, loss of work, penal servitude, banishment, “wooden horse riding” and finally military transcription. Even though previous re-search, in the field of Swedish specialized courts, is almost non existent evidence confirms great similarities between the Stora Kopparberget mining court and Sala mining court. This essay will, hopefully, enrich our knowledge of specialized courts, of 17th century mining industry and society and let us reach a broader understanding of the working conditions of the mountain.
15

Nitrogen transformations at the Kiruna mine : The use of stable nitrogen isotopes to trace nitrogen-transforming processes

Nilsson, Lino January 2013 (has links)
Release of different nitrogen compounds can cause eutrophication in lakes and rivers whichcan lead to oxygen-free environments in bottom water and in the sediment and can in turnlead to fish-deaths. Ammonium can be toxic to biota and nitrate can in high concentrationeven be toxic to humans. WHO has released a limit for nitrate concentration in drinking waterof 10mg/l. The LKAB mine in Kiruna is the largest underground iron mine in the world and isprospecting, mining and refining iron ore, with an annual production of around 28 milliontons. Release of different nitrogen compounds as a result of the explosives used during themining operations has been a known problem for some time; however the processes affectingnitrogen during the water transport have never been fully investigated. The main objective of this MSc thesis is to determine if changes in nitrogen and oxygenisotope composition can be used as a tracer for nitrogen transformation processes in the minewater at LKABs underground mine in Kiruna. Water samples were collected at key points in the water transport system and were analyzedfor isotopic composition. Isotopic and chemical data revealed two different sources of nitrateand ammonium, undetonated explosives and leachate from waste rocks. Three differentnitrogen changing processes affecting concentration of nitrate and ammonium were found:ammonium volatilization, nitrification and sorption. It was not possible to quantify theseprocesses individually. No processes which decrease the nitrate concentration were found.
16

Staden som gruva : I fäders spår för framtids segrar / Urban mining : Past, present and future of recycling of disconnected underground infrasystems

Gustafsson, Marcus January 2012 (has links)
Naturens mineralresurser är till viss del utnyttjade och uttömda, och framtiden är osäker och omdebatterad. Ingen vet säkert exakt hur mycket metall som finns kvar i jordskorpan, hur mycket som går att utvinna eller hur länge resurserna kommer att räcka. Samtidigt har vi byggt in rena metallådror i våra städer i form av elkablar, telekablar och fjärrvärmerör. Många av dem används givetvis, men många är också uttjänta och urkopplade, och därmed tillgängliga för återvinning.Syftet med denna studie är att klarlägga hinder, drivkrafter och möjligheter för metallåtervinning av urkopplade infrasystem i mark inom lokala el-, tele- och fjärrvärmenät i Sverige. För att uppnå detta tillfrågades Sveriges tio största ägare av underjordiska lokala elnät om bl.a. sina rutiner för urkopplade ledningar och genomförda projekt där ledningar tagits upp. Samma bolag frågades även om sina respektive fjärrvärmenät. Utöver dessa ingick telenätägaren Skanova, kommuner med anknytning till de tillfrågade nätägarna, metallåtervinningsföretag, entreprenörer och myndigheter i studien. Dessutom gjordes en litteraturstudie på området metallåtervinning.De viktigaste drivkrafterna för upptagning och återvinning av urkopplade infrasystem i mark visade sig vara ekonomi, utrymmeskonflikt i ledningsgatorna, krav i form av lagar, avtal eller egen policy, samt risk för miljöpåverkan. Alla förutom utrymmeskonflikt kan dessutom, beroende på omständigheterna, vara hinder för återvinning. En viktig möjliggörande faktor är att ledningens läge är känt och att den inte riskerar att förväxlas med andra ledningar.I dag är det vanligt att ledningar ligger kvar i marken en tid efter att de tagits ur bruk. I de fall de tas upp sker det ofta i samband med andra grävarbeten längs ledningen. Miljörisker, utrymmeskonflikter och krav kan tvinga fram upptagning av en ledning, medan ekonomi, med nuvarande metallpriser, är mer av ett hinder. Om återvinning av ledningar i mark ska bli norm krävs det att lönsamheten ökar. Detta kan ske genom ökade metallpriser, användande av alternativa metoder för upptagning, ett bredare synsätt som tar hänsyn till att återvinning kan minska behovet av primära metallresurser, eller kanske subventionering av återvunnen metall. Hårdare lagstiftning skulle kunna tvinga fram ökad återvinning, men för att alla inblandade ska vara med på det är det bättre att låta marknadskrafterna styra och att det baseras på frivillighet.Om återvinningen av infrasystem i mark ska ökas måste det göras insatser på flera nivåer. Nya metoder, som utvecklas av fristående entreprenörer, kan göra återvinning mer lönsam. Nationella mål och riktlinjer bör tas fram av Naturvårdsverket för att vägleda nätägare och markägare. Om ekonomiska styrmedel behövs måste det beslutas om av Riksdagen. Branschorganisationer och länsstyrelser kan samordna arbetet bland sina medlemmar och inom sina regioner. Markägarna måste sedan komma överens med nätägarna om vad som är lämpligt och vad som fungerar för just deras områden. / Earth’s natural mineral resources have, to some extent, already been used and depleted, and the future is both uncertain and debated. No one knows for certain exactly how much metal there is left in Earth’s crust, how much we can extract or for how long the resources are going to last. Meanwhile, we have installed ores of metal in our cities, in the form of electric cables, telecom cables and district heating pipes. Many of these are of course in use, but many have also reached end of life and been disconnected, and are thus available for recycling.The purpose of this study is to clarify barriers, drivers and enablers for metal recycling of disconnected underground infrasystems within the local electricity, telecom and district heating networks in Sweden. In order to do this, ten of Sweden’s largest owners of local underground electricity networks were asked e.g. about their routines and about projects where cables were taken up. The same companies were also asked about their district heating networks. Apart from these, the study included the telecom network owner Skanova, municipalities with connections to the ten electricity network companies, metal recycling companies, contractors and authorities. Furthermore, a literature study on metal recycling was conducted.The main drivers for taking up and recycling disconnected underground infrasystems proved to be economy, conflicts of space in the ground, rules and regulations in terms of legislations, contracts or company policies, and environmental impact risks. All of these, except for conflicts of space, could also, depending on the circumstances, be barriers for recycling. One important enabler is to know the exact position of the cables or pipes and that they don’t risk being confused with other cables or pipes.Presently, cables and pipes are commonly left in the ground for some time after they have been taken out of service. When they are eventually taken up, it is often done simultaneously with other digging operations along the cable or pipe. Environmental risks, conflicts of space and rules and regulations can force the excavation of cables and pipes, while economy, with current metal prices, is more of a barrier. If recycling of underground infrasystems is to become norm, the profitability needs to increase. This can occur through increased metal prices, use of alternative excavation methods, a wider view that takes into account that increased recycling can decrease the need for primary metal resources, or perhaps through subsidization of recycled metals. Tougher legislations could force a higher recycling rate, but in order to include all involved parts and not upset anyone, it is better to let the market drive and base it all on free will.If the recycling of underground infrasystems is to increase, efforts must be made on several different levels. New methods, developed by independent entrepreneurs, could make recycling more profitable. National goals and guidelines should be presented by the Swedish EPA, to guide and direct network owners and landlords. If financial instruments are needed, these must be decided upon by the parliament. Business associations and county administrations can coordinate the work among their members and within their regions. The landlords and the network owners must then agree on what is appropriate and applicable for their specific areas.
17

Potential för produktion av surt lakvattten och kvantifiering av kvävelakning från restprodukter från gruvindustrin: En fallstudie från Kiirunavaara-gruvan / Potential for Production of Acid Mine Drainage and Quantification of Nitrogen Leakage in Mine Wastes: A Case Study from the Kiirunavaara mine in Sweden

Smedborn Paulsson, Eva January 2016 (has links)
Gruvavfall, i form av gråberg, från Kiirunavaara-gruvan i Kiruna, norra Sverige undersöktes för att se om surt lakvatten kan bildas från gråberget och om detta kan ha en påverkan på hur mycket kväve som kan lakas ut från gråberget. För detta ändamål gjordes dels en mineralogisk undersökning av gråberget, med siktning, röntgendiffraktion (XRD) och grundämnesanalys och dels laborativa skakförsök. Från skakförsöken, där olika kornstorlekar (8-16 mm, 2-4 mm och mindre än 1 mm) blandades med avjoniserat vatten med L/S-kvoten 10, kunde förändringar i pH, alkalinitet och lösta joner undersökas över en 10-veckors period.                       De främsta mineralen i gråberget i Kiirunavaara visades vara plagioklas, kvarts och biotit. I gråberget finns även 18 g pyrit/kg gråberg. Skakförsöken indikerar att lakvattnet från gråberget i Kiirunavaara är alkaliskt med ett pH över 9. Vittring av sulfidmineral sker, men neutraliseras av buffrande mineral som kalcit och ingen potential till produktion av surt lakvatten finns. Kväveutlakningen sker främst under de första dygnen, men mer än hälften av de kväveföreningar som antas finnas i gråberget lakas inte ut. Både nitrat och ammonium visade signifikanta korrelationer med pH, där högre pH-värden tydde på högre nitratkoncentrationer och lägre pH-värden på högre ammoniumkoncentrationer. Detta indikerar att även om inget samband kunde ses mellan produktion av surt lakvatten och kväveutlakning, så är mängden av olika kväveföreningar som lakas ut beroende av lakvattnets pH-värde. / Mining waste rock from the Kiirunavaara-mine in northern Sweden was studied to determine if there is a potential for production of acid mine drainage (AMD), if there is a leaching of nitrogen compounds from the waste rock and if a correlation between the two processes can be seen. A mineralogical characterization of the waste rock was done through dry sieving, X-Ray Diffraction (XRD) and elemental analysis. Through shake flask experiments, where waste rock of three different grain sizes (8-16 mm, 2-4 mm and less than 1 mm) were mixed with deionized water (L:S-ratio of 10), the change in pH, alkalinity and dissolved ions during a 10-week period was determined.                       The waste rock in Kiirunavaara was found to consist mainly of plagioclase, quartz and biotite, but the waste rock also contains 18 g pyrite per kg waste rock. The shake flask experiments indicate that the mine drainage from the waste rock in Kiirunavaara is alkaline, with a pH above 9. Weathering of sulphide minerals occur, but are neutralised by buffering minerals such as calcite and thus no potential for AMD-production exists. The leaking of nitrogen compounds occurs mainly during the first few days. Both ammonium and nitrate showed significant correlations with pH, where lower pH-values typically exhibited higher ammonium concentrations, while higher pH-values correlated with higher nitrate concentrations.

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