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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.
1

Kartläggning av flotationskinetik i Garpenbergs anrikningsverk.

Brånn, Emma January 2019 (has links)
Sammanfattning Boliden Mineral AB är intresserade av att göra en omfattande kartläggning av flotationskinetiken i alla sina anrikningsverk. Kartläggning av ett anrikningsverk är en viktig pusselbit för att förbättra processen, se eventuella flaskhalsar och utveckla framtida processmodeller. I en flotationsprocess är det önskvärt med höga utbyten, snabb flotation och ett högt tonnage. Syftet var att göra en kartläggning av flotationsprocessen i Garpenbergs anrikningsverk. Den praktiska delen av examensarbetet var att göra flotationsförsök i labbskala. Resultatet från flotationsförsöken anpassades med hjälp av Minitab för att se vilken första ordningens kinetikmodell som passar bäst. Genom att använda olika typer av kinetikmodeller så anpassas kinetiken till labbflotationsstudier, det är till för att förfina modellerna vid uppskalningsberäkningar och utvärderingar av nya malmlinser. De tre första ordningens kinetikmodeller som jämförts är den klassiska modellen, Klimpels modell och den fullständigt blandade modellen. Med dessa gjordes en kartläggning av flotationskinetiken i Garpenbergs anrikningsverk. Materialet som flotationsförsöken utfördes på är tagna från anrikningsverket, där värdemineralen är kopparkis, blyglans och zinkblände. Kartläggningen av flotationskinetiken i Garpenberg visas i resultatdelen för varje provtagningspunkt med en sammanfattande diskussionsdel om varje del av processen. Koppar- och blyflotationen visar att det är höga utbyten genom hela processen och att ommalningsdelen i kretsen ger en del förbättringar i utbytet. Vad resultatet visar är att verket går optimalt, och att nästan allt koppar och bly tas ut inom 10 minuters flotation. Modellen som passar bäst är den klassiska modellen för alla provpunkter, förutom för ingående malm där Klimpels modell passar bäst. Kartläggningen för zinkflotationen visar att det är höga utbyten genom hela processen. I sista steget i zinkflotationskretsen är provpunkten andra repeteringen, där är det svårt att flotera enbart zink eftersom det är lätt att gångartsmineral också floteras i detta steg. Övriga provtagningspunkter tyder på att verket går optimalt och att det mesta av Zn är uttaget inom 10 minuters flotationstid. Modellen som passar bäst är den klassiska modellen för alla provpunkter, förutom för andra Zn repeteringskoncentrat där Klimpels modell är bäst. Malkretsflotationens resultatdel visar en flotationskrets med bra utbyte, men på grund av den grövre partikelstorleken floterades det långsammare än övriga flotationstester. För bly passar Klimpels modell bäst och för koppar passar den klassiska modellen bäst.
2

Herrgårdshushållets organisationsutveckling på Garpenbergs herrgård 1800-1899 : En studie om herrgårdens tjänstefolk och dess förändring över tid

Karhukorpi, Henry January 2017 (has links)
This essay examines how the organization and size of the mansion household changed atGarpenberg’s mansion between 1800-1899, in the terms of servants, their occupation and wherefrom they were recruited. This has been done by using catechetical lengths as the primary source.By looking at which types of servants that worked within the mansion, and how the structurechanged, this study tries to answer how the organization and size of the mansion household changedduring the 19th century. This survey has shown that the total amount of servants at Garpenberg’smansion increased during the time period, but the mansion household itself remained relativelyconstant throughout the century. In addition, more servants began to form their own households andwere partly no longer dependent of the gentry that owned the mansion.
3

Kvalitetssäkrad Bultplansgenerering

Hugoson, Alexander, Précenth, Henrik January 2016 (has links)
Detta examensarbete inom bergmekanik har utförts på uppdrag av Boliden under perioden april-maj 2016 i Bolidens underjordsgruva i Garpenberg. Bultriggarna i Garpenberg är utrustade med ett nytt system för att hjälpa operatören att positionera bergbultar enligt planerade bultmönster. Detta innebär att det önskade bultavståndet läggs manuellt in i maskinens dator och genom att referera till två tidigare installerade bultar genereras en plan för nästa bultkrans. Syftet med examensarbetet var att utföra en kvalitetskontroll gällande bultriggens navigeringssystem genom referensbultning. Genom att jämföra bultriggarnas datalogg mot mätningarna av verkligt utfall undersöktes om bultarna följde den angivna förstärkningsplanen. Arbetet har utförts genom att mäta in 8 bultkransar (totalt 104 installerade bultar) med  totalstation. Datan har sedan jämförs med bultriggarnas datalogg som automatisk genereras i mjukvaran vid installationen av varje bult. Datan har sedan analyserats med hjälp av datorprogrammen AutoCAD och Microsoft Excel för att beräkna avvikelsen mellan bultriggarnas datalogg och mätningarna av verkligt utfall (medelvärden, standardavvikelse och normalfördelning). Resultatet av mätningarna visar att 30,4 % av samtliga avvikelser från bultriggens datalogg ligger i intervallet 0-3 centimeter. Analysen visar en total standardavvikelse på 0,103 meter. Då analysen av avvikelser från bultriggens datalogg förutsätter att bultriggarnas sensorer är korrekta i sin precision har en kontrollmätning genomförts. / This thesis in rock mechanics was carried out on behalf of Boliden during the period of April to May 2016 at Boliden underground mine in Garpenberg. The bolting rigs in Garpenberg are equipped with a new system to assist the operator to position the rock bolts according to the planned bolting pattern. This means that the planned bolt spacing is manually inserted in the bolt positioning software and by referring to two previously installed bolts the planned location of the next bolting fan is generated and shown in the software. The aim of the thesis was to perform a quality control regarding the bolting rigs navigation system by reference bolting. Through comparing the bolting rigs data log with the measurements of the actual outcome it was determined if the location of the bolts were positioned according to the specified rock support plan. The work was performed by measuring the location of eight bolting fans (a total of 104 installed bolts) with a total station. The data was then compared with a data log that is automatically generated in the software at the installation of each bolt. The data has mainly been analysed using computer software such as AutoCAD and Microsoft Excel in order to calculate deviation of the bolting rigs data log and the measurements of actual outcome (mean values, standard deviation and normal distribution). The result of the measurements shows that 30.4% of all rock bolts are in the range of 0-3 centimetres from their planned locations. The analysis shows a total standard deviation of 0.103 metres. The analysis of deviations requires that the sensors on the joints of the bolting rigs are calibrated for the bolt positioning software and therefore control measurements were carried out.
4

Identification and strength classification of weakness zones in the Garpenberg mine based on measurement while drilling (MWD)

Peroulakis, Ioannis January 2022 (has links)
Boliden’s Garpenberg mine produces Zn-Pb-Ag(Cu-Au) using a sublevel stoping with pastefill mining method. The orebody is strongly affected by the existence of weakness zones mainly consisting of Talc Schist and Phlogopite Schist which affect the design, planning and production of the stope. To mine the ore two drifts, one below and one above the ore section, are excavated typically at a distance of 25 meters. Afterwards parallell longhole drilling is done for the primary stopes and drilling in a fan pattern is done for secondary stopes by automated remotely controlled SIMBA drills. Those drill rigs are equipped with sensors that record drilling parameters during drilling, so called Measurements While Drilling. The drilling parameters that are recorded are depth, time, penetration rate, percussive pressure, feed pressure, dampening pressure, rotation pressure and flush pressure at selected intervals. This thesis aims to identify the mentioned weakness zones using the existing MWD data. First of all, this thesis contains six chapters. The first is a detailed introduction to the problem. The second chapter describes the geology, the mining method used in Garpenberg and also includes a brief section on how SIMBA drills work. The third chapter consists of the MWD theory, literature review and the methodology used to come up with the solution of the stated problem. In the fourth chapter is described how a successful method was developed using 3D models created from MWD data and geologic maps to identify the weakness zones and classify the rock based on four filters created. The fifth chapter is a detailed discussion of the results and findings of this thesis. Finally, the sixth chapter is the conclusion.
5

Investigation of the zinc re-grinding circuit at Boliden Garpenberg

Merum, Nils January 2021 (has links)
Boliden’s mineral processing plant in Garpenberg wanted to investigate their zinc-regrinding circuit. The re-grinding circuit had performed subpar when running as the total recovery of zinc was lowered and problem with the dewatering of the final concentrates was also noted. Therefore, the zinc re-grinding circuit is currently not being used. Furthermore, it was noted during investigations about silicate depressant that the zinc circuit had problems with coarse sized sphalerite particles locked with silica. Which could perhaps be liberated with the re-grinding circuit. The purpose was therefore to investigate how a re-grinding step could be used to liberate locked sphalerite particles from gangue. The practical part of the thesis involved lab-scale SMD-mill, re-grinding of the scavenger concentrate and cleaner tailings which are the two streams being fed to the SMD-mill in the plant. The re-grind was done in three fractions: bulk, +90µm and +125 µm fraction with subsequent lab-scale flotation afterwards to identify how the re-grinding effected the flotation results. Also, a small QEMSCAN analysis was performed for the +90 µm fraction to identify how liberation was improved by re-grinding. The flotation trials were performed with two references and two different intensities for the re-grinds.  The results showed an overall increase in grade of zinc in the concentrate with increased grinding for all the trials. SiO2 and MgO content (typical elements for silicate gangue) was also reduced in the zinc concentrate, showing that re-grinding helped liberate locked sphalerite particles. The QEMSCAN results showed that the liberation of sphalerite particles in the +90 µm fractions increased with re-grinding. For the bulk fraction scavenger concentrate the zinc recovery increased slightly, for the +90 µm fraction scavenger concentrate, a slight decrease in zinc recovery could be seen after re-grinding. The decrease in recovery was larger for the cleaner tailings (bulk and +90 µm) and was decreased further with increased grinding. However, for the +125 µm fraction tests, zinc recovery was increased for both scavenger concentrate and cleaner tailing. The references showed an overall high recovery but a zinc grade in the concentrate close to the feed grade of zinc and contained a high grade of SiO2. Indicating that without re-grinding the amount of free sphalerite is low. Overall, the re-grind and flotation tests pointed towards that value can be created for the plant by re-grinding the scavenger concentrate and cleaner tailing.
6

Framtidens Gruvlavar: En Undersökning av Trä som Byggmaterial

Blom, Victor, Andersson, Fabian January 2024 (has links)
Dagens gruvdrift omfattar huvudsakligen två metoder för malmbrytning: dagbrott och underjordsbrytning. Vid dagbrott öppnas gruvan ovan jord, medan underjordsbrytning involverar utvinning under mark och transport till marknivån med hjälp av ett gruvspel. Den struktur som bär upp detta gruvspel över schaktet kallas gruvlave. Ursprungligen byggdes gruvlavar främst i trä, men med ökande schaktdjup och lastkrav övergick industrin till stål och betong som de primära byggmaterialen. Betong, sammansatt av grus, krossat berg, sten, cement och vatten, betraktas som ett hållfast material, men dess tillverkningsprocess genererar betydande koldioxidutsläpp med negativ klimatpåverkan. På samma sätt har ståltillverkningen en betydande miljöpåverkan, där industrisektorn svarar för en betydande andel av Sveriges totala utsläpp, främst från stål- och järnindustrin. Med detta som bakgrund har Boliden Mineral AB (hädanefter benämnt som Boliden) genomfört en förstudie på ett expansionsprojekt med syfte att öka produktionstakten i gruvan. Ett framträdande mål i projektet är att minimera eller eliminera CO2-utsläpp för att möjliggöra produktionen av "no-carbon zinc." Trots eventuell minimering av gruvdriftens miljöpåverkan erkänns att byggnationer alltid kommer att ha en viss inverkan på miljön. För att minska byggnationernas miljöpåverkan föreslås trä som ett alternativt byggmaterial. Trä är en förnybar resurs med låg miljöpåverkan och hög tillgänglighet, och det betraktas som potentiellt fördelaktigt för konstruktion av framtida gruvlavar. Detta ligger till grund för det här examensarbete, som fokusera på att analysera och jämföra valet av byggmaterial för en ny gruvlave i Bolidens expansionsprojekt. Studien undersöker specifikt byggmaterialets påverkan genom att jämföra användningen av betong och stål med trä som primärt byggmaterial. Undersökningen utförs vid Bolidens gruva i Garpenberg, belägen knappt 3 mil norr om Avesta. De frågeställningar som arbetet kretsar runt är följande: • Är det tekniskt genomförbart att konstruera den nya gruvlaven i expansionsprojektet vid Garpenberg i trä i stället för betong och stål? • Hur skiljer sig klimatavtrycket mellan den nya gruvlaven i expansionsprojektet vid Garpenberg i trä jämfört med i betong och stål, med hänsyn till materialåtgång? • Är det ekonomiskt försvarbart att bygga den nya gruvlaven i trä i stället för betong och stål i expansionsprojektet vid Garpenberg? För att svara på frågeställningarna användes två huvudsakliga metoder: litteraturstudie och omfattande beräkningar. Båda metoderna bidrog med unika insikter, och tillsammans gav de en djup förståelse av ämnet, vilket möjliggjorde relevanta slutsatser. Baserat på detta arbete kan de formulerade frågeställningarna besvaras och diskuteras. Tekniskt sett är det möjligt att konstruera den nya gruvlaven i trä i stället för betong och stål vid expansionsprojektet i Garpenberg. Emellertid kräver detta en grundlig utredning och hänsyn till flera parametrar, bland annat brand- och fuktfrågor. Resultaten visar att konstruktionen av en gruvlave i trä, jämfört med betong och stål, ger en avsevärt lägre klimatpåverkan. Beräkningarna indikerar ca 35 % av den koldioxidekvivalent som genereras av betong- och stållaven, vilket pekar på betydande miljövinster genom användning av trä. Denna slutsats understryker trämaterialens positiva bidrag till hållbarhet vid byggandet av gruvlavar och betonar vikten av att överväga materialval med hänsyn till deras klimatpåverkan, vilket kan vara avgörande för framtida beslut inom gruvsektorn. Kostnadsanalysen motiverar användning av trä som huvudsakligt byggnadsmaterial för gruvlavar, kostnaden för en träbaserad konstruktion är endast 76 % av kostnaden för en likvärdig i stål och betong. Examensarbetet utmynnar i att trä kan vara en kostnadseffektiv och hållbar lösning för gruvlavar, vilket motiverar fortsatt undersökning av dess möjligheter. Med grund i detta kan trä anses som ett lämpligt byggnadsmaterial för kommande gruvlavar. / Today's mining primarily involves two ore extraction methods: open-pit mining and underground mining. Open-pit mining exposes the mine above ground, while underground mining involves extraction beneath the surface, with ore transported to ground level using a mine hoist. The structure supporting this hoist over the shaft is referred to as a minehead frame. Originally constructed mainly in wood, minehead frames transitioned to steel and concrete as mining depths and load requirements increased. Concrete, comprising gravel, crushed rock, stone, cement, and water, is considered a sustainable material, but its manufacturing process generates significant carbon dioxide emissions with adverse climate impact. Similarly, steel production significantly impacts the environment, with the industrial sector contributing substantially to Sweden's total emissions, particularly from the steel and iron industry. Considering these challenges, Boliden Mineral AB (Hereinafter referred to as Boliden) has conducted a pre-study for an expansion project aimed at increasing the production rate in the mine. A prominent goal in the project is to minimize or eliminate CO2 emissions to enable the production of "no-carbon zinc." Despite potential reductions in the environmental impact of mining operations, it is acknowledged that construction activities will always have some level of environmental impact. To mitigate the environmental impact of construction, timber is proposed as an alternative building material. Timber, a renewable resource with low environmental impact and high availability, is recognized as potentially advantageous for future minehead frame construction. This serves as the foundation for this thesis, which focuses on analyzing and comparing a new minehead frame in Boliden's expansion project. The study specifically investigates the environmental impact of construction by comparing the use of concrete and steel with timber as the primary building material. The examination is conducted at Boliden's Garpenberg mine, located nearly 3 miles north of Avesta. The research questions revolve around: Is it technically feasible to construct the new minehead frame in wood instead of concrete and steel in the Garpenberg expansion project? How does the carbon footprint differ between the new wooden minehead frame in the Garpenberg expansion project compared to concrete and steel, considering material consumption? Is it economically justifiable to build the new minehead frame in wood instead of concrete and steel in the Garpenberg expansion project? To address these questions, two main methods were employed: literature review, calculations, and communication with experts. Each method provided unique insights, forming a comprehensive understanding of the subject, allowing for relevant conclusions. Based on this work, the formulated questions can be answered and discussed. Technically, it is possible to construct the new minehead frame in timber instead of concrete and steel in the Garpenberg expansion project. However, this requires a thorough investigation, considering various parameters, including fire and moisture considerations. Results indicate that constructing a timber minehead frame, compared to concrete and steel, significantly reduces the carbon footprint. Calculations suggest only 35 % of the carbon dioxide equivalent generated by concrete and steel minehead frames, highlighting substantial environmental benefits with timber use. This conclusion underscores the positive contribution of wood materials to sustainability in minehead frame construction and emphasizes the importance of considering material choices based on their climate impact, which can be critical for future decisions in the mining sector. The cost analysis justifies the use of timber as the primary building material for mining headframes, as the cost of a timber-based construction is only 76 % of that of an equivalent structure in steel and concrete. The thesis concludes that timber could be a cost-effective and sustainable solution for mining headframes, warranting further investigation into its potential. Based on this, timber may be considered a suitable building material for future mining headframes.
7

EXAMINATION OF MICRO-SCALE SULFIDE DISTRIBUTION FOR THE GOLD MINERALIZATION IN THE LAPPBERGET DEPOSIT, GARPENBERG MINE, SWEDEN: TOWARDS A GEOMETALLURGICAL APPROACH

Barbosa, Leo January 2021 (has links)
Ore characterization studies are of great importance to the mining industry, especially when dealing with precious metals by-products. It is a way towards increasing mining efficiency. The Swedish Boliden’s Zn–Pb–Ag–(Cu–Au) Lappberget Deposit is the main ore body at the Garpenberg Mine producing concentrates of zinc, lead, copper, and a gravity concentrate of silver and gold, which accounts for a significant revenue for the mine. Garpenberg Mine is an ancient and traditional mining site in Sweden, nonetheless the Lappberget deposit is a relatively recent discovery and there are still on-going studies on this ore body. More recently detailed ore investigations have been carried out on the sulfides and silver mineralization in different geological domains within the Lappberget deposit. In this context, the present work is focused on investigating the gold mineralization of the deposit, aiming to study the occurrence and distribution of gold minerals, characterize the gold in the ore and how its characteristics affect gold recoveries during its processing. To achieve these goals, different investigative methods were applied on drill core samples of the footwall disseminated to semi-massive mineralization (FWD), and on samples from the gravity concentrator at Boliden’s processing plant. The techniques applied were optical microscopy, scanning electron microscopy, energy dispersive x-ray spectrometry, electron probe microanalysis, laser ablation inductively couple plasma mass spectrometry, and bulk chemical analysis. The main findings pointed electrum as the main gold mineral, occurring with a strong sulfide association, in a variety of textures and grain sizes. The study also identified the occurrence of Au-Bi alloy, not previously described in literature of the Garpenberg region. The potential of invisible gold in the sulfide carriers was also a subject of investigation, as well as the evaluation of the characteristics of the samples from the gravity concentrator.
8

Factors governing marble lightness in peripheral alteration haloes around carbonate-hosted Zn-Pb-Ag-(Cu-Au) deposits, Garpenberg, Sweden

Eriksson, Marcus January 2020 (has links)
A Master thesis about the Garpenberg deposit located in Bergslagen, a lithotectonic domain, with a mining history that might date back as far as 350 BC. Marble- and skarn-hosted sulfide deposits are found in the area, which creates the opportunity to mine both limestone and sulfidic ore in a single mine. Garpenberg is such a location hence this thesis, which aims to quantify the factors governing spectrophotometric lightness in marble at the Dammjön ore body. The work is mainly based on five drill cores which were logged and sampled. A total of twenty-seven samples were characterized using lithogeochemical analysis and thin-section analysis. The amount of Acid Insoluble Residue (AIR), magnetic minerals and the spectrophotometric lightness were determined for the same samples. The calcite marble was divided into seven different varieties; 1) calcite marble breccia, 2) light, 3) grey, 4) green, 5) banded salmon pink, 6) ophicalcite and 7) spotted calcite marble. The dolomite marble is white to grey in color and skarn minerals are common and varies between 5-20 vol.%. Grey and light calcite marble are the varieties with the highest spectrophotometric lightness, and it could be shown that the lightness increases with a decreasing amount of titanium, aluminum and zirconium which are chemical proxies for mineralogical impurities of originally volcaniclastic origin. High-quality calcite marble is a potentially economic by-product at the Garpenberg mine, the lightest samples are nearly as light as the light standard used during analysis (92.45 out of 100%). The lightest marble is also the chemically most pure which means that the calcium oxide (CaO) and total-carbon content are high. Key geological factors detrimental to lightness and purity are the primary composition, which is determined by the admixture of volcaniclastic material in the limestone precursor. Hydrothermal alteration with the addition of silicates, sulfides and oxides forms a halo around the massive sulfide lenses. Dolomite marble, which is more proximal to ore, is richer in manganese and sulfides, and not as light as the calcite marble at Dammsjön.
9

Historical mining of Fe-Ca ore in Garpenberg, Sweden. : A study based on lake sediment geochemistry from Finnhytte-dammsjön.

Eliasson, Morgan January 2023 (has links)
It is well established that mining and metallurgy on a larger scale in Sweden originated in Bergslagen. The historical mining district Garpenberg in Bergslagen presently show the oldest signs of mining in Sweden (2300 BP) based on a study of a lake sediment profile from Gruvsjön. This report focuses on the mining history around Finnhytte-dammsjön (Garpenberg) to assess when the first signs of mining occur, what type of ore was being mined, when the first sign of modern mining was observed and when the lake development stabilized. A complete sediment profile was sampled from Finnhytte-dammsjön which was analyzed with X-Ray Fluorescence spectroscopy. An age-depth model was created for the sediment profile using the introduction of Norway Spruce (Picea Abies) pollen and by matching known peaks in historical atmospheric pollution of Pb as points of reference. Increased Fe concentrations (3.6 ± 0.4 %) compared to deeper sections (2.6 ± 0.2 %) was observed which were well correlated with Ca (R2: 0.73). Indications of increased Fe concentrations relative to Ca was found from 2000 BP. Stabilization of LOI550 and changes in sediment geochemistry indicates that a steady state in the lake development was reached around 4600 BP. Major increases in Zn and Cu that was presumed to be from modern mining was observed from 1800 CE. This report concludes that Fe-rich dolomite or skarn was mined from 500 CE with indications that mining started as early as 2000 BP.

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