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1
Buyukakinci, Ergin. "Extraction Of Nickel From Lateritic Ores." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609291/index.pdf.
Full textAbstract:
The aim of this study was to extract nickel and cobalt from the lateritic nickel ores of Gördes region by hydrometallurgical methods under the optimum conditions. Limonitic and nontronitic types of Gö
rdes lateritic nickel ores were used during experiments. Agitative and column leaching experiments at atmospheric pressure were conducted with various parameters
these were duration, temperature and initial sulfuric acid concentration of leach solution. It was shown that in agitative leaching, under the optimum conditions that were determined as 24 hours of leaching at 95°
C with initial sulfuric acid concentration of 192.1 g/L for nontronite and 240.1 g/L for limonite, nickel and cobalt extractions were 96.0% and 63.4% for nontronite
93.1% and 75.0% for limonite, respectively. Overall acid consumptions of ores were calculated as 669 kg H2SO4/ton dry ore for nontronitic type nickel ore and 714 kg H2SO4/ton dry ore for limonitic type nickel ore. Column leaching experiments also showed that nickel and cobalt could be extracted from both ore types by heap leaching. Nontronite type of laterite was found to be more suitable for column leaching by sulfuric acid. In column leaching, the calculated nickel and cobalt extractions were 83.9% and 55.2% for nontronite after 122 days of leaching with 100 g/L sulfuric acid concentration. Acid consumption of nontronite was found to be 462 kg H2SO4/ton dry ore.
2
Kose, Caner Hakki. "Hydrometallurgical Processing Of Lateritic Nickel Ores." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612295/index.pdf.
Full textAbstract:
The objective of this thesis study is to recover nickel and cobalt at maximum efficiency from column leach liquor of lateritic nickel ores existing in Gördes region of Manisa by performing various hydrometallurgical methods under the optimum conditions. This column leach solution of nontronite type lateritic nickel ore was initially neutralized and purified from its basic impurities by a two stage iron removal process under the optimum conditions determined experimentally. Then, nickel and cobalt were precipitated in the form of mixed hydroxide precipitate from the purified leach solution by a two stage precipitation method called &ldquo
MHP&rdquo
and a manganese removal process was carried out also under the optimum conditions determined. By decreasing Mn concentration with this process to an acceptable level yielding at most 10% Mn in hydroxide precipitate, it was possible to produce a qualified MHP product suitable to the current marketing and standard conditions. As a result of this thesis study, the experiments conducted showed that by recycle leaching with sulfuric acid about 81% of Ni and 63% of Co in the lateritic nickel ore (9.72 kg Ni / ton of ore and 0.28 kg Co / ton of ore) could be extracted as mixed hydroxide precipitate by MHP method. The MHP product contains 41.9% Ni, 1.0% Co, 2.3% Mn, 0.06% Al, 1.5% Mg, 0.02% Fe, 0.01% Cr, 0.25% Zn, 0.03% Cu and 4.73% S.
3
Ho, Elizabeth M. "An electrochemical study of reactions of nickel matte in acid media." Murdoch University, 1998. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20060815.140539.
Full textAbstract:
Nickel matte is a nickel &de concentrate produced by smelting. It consists mainly of two components: a nickel-copper alloy and heazlewoodite (Ni3S2); but also contains
varying amounts of djurleite,Cu 1.96 S.There are several hydrometallurgical routes for processing nickel matte. The most recent of these involves an oxidative leach in acid
chloride or sulfate solution. Nickel is subsequently recovered fiom the leach solution by electrowinning or by hydrogen reduction. In the work described in this thesis,
various aspects of the acid leaching of nickel matte are investigated using mostly
electrochemical methods.
The first section concerns the use of copper(II) as an oxidant for the alloy component of nickel matte. In this cementation reaction, nickel goes into solution while copper is deposited on the dissolving metal swf8ce. The same reaction is important in removing traces of copper present in the nickel solution. Here nickel powder is added to the process liquor. A survey of the literature pertaining to the cementation of copper by nickel shows that there is considerable dispute as to the conditions under which cementation takes place. Evans' diagrams for the cementation reaction were constructed by superimposing the polarisation curves for the oxidation of nickel and
the reduction of copper. It was found that cementation occurred provided that the two polarisation curves intersected in the region of active nickel dissolution. Outside this region, a copper deposit could not be seen.
The second part of the thesis presents some investigations into the electrochemistry of nickel sulfides and nickel matte, and compares both chloride and sulfate media.
Oxidation and dissolution rates of nickel matte powders using copper(I1) as an oxidant were also carried out. Dissolution was chemically controlled and so the rate was very dependent upon temperature and solution potential. Displacement of copper(II) from solution to form copper sulfide was also found to be important.
In addition to the above studies, which relate directly to the oxidative leaching ofnickel matte, an investigation of the oxidation of HzS to sulfUr in acidic solution was
carried out. S u k deposition was found to be strongly dependent on substrate and pH. Under some conditions, two types of sulfUr were deposited, with the more crystalline s u k being reduced at the more negative potential.
4
Ho, Elizabeth M. "An electrochemical study of reactions of nickel matte in acid media." Thesis, Ho, Elizabeth M. (1998) An electrochemical study of reactions of nickel matte in acid media. PhD thesis, Murdoch University, 1998. https://researchrepository.murdoch.edu.au/id/eprint/98/.
Full textAbstract:
Nickel matte is a nickel sulfide concentrate produced by smelting. It consists mainly of two components: a nickel-copper alloy and heazlewoodite (Ni3S2); but also contains varying amounts of djurleite, Cu1.96S. There are several hydrometallurgical routes for processing nickel matte. The most recent of these involves an oxidative leach in acid chloride or sulfate solution. Nickel is subsequently recovered fiom the leach solution by electrowinning or by hydrogen reduction. In the work described in this thesis, various aspects of the acid leaching of nickel matte are investigated using mostly electrochemical methods.
The first section concerns the use of copper(II) as an oxidant for the alloy component of nickel matte. In this cementation reaction, nickel goes into solution while copper is deposited on the dissolving metal swf8ce. The same reaction is important in removing traces of copper present in the nickel solution. Here nickel powder is added to the process liquor. A survey of the literature pertaining to the cementation of copper by nickel shows that there is considerable dispute as to the conditions under which cementation takes place. Evans' diagrams for the cementation reaction were constructed by superimposing the polarisation curves for the oxidation of nickel and the reduction of copper. It was found that cementation occurred provided that the two polarisation curves intersected in the region of active nickel dissolution. Outside this region, a copper deposit could not be seen.
The second part of the thesis presents some investigations into the electrochemistry of nickel sulfides and nickel matte, and compares both chloride and sulfate media. Oxidation and dissolution rates of nickel matte powders using copper(I1) as an oxidant were also carried out. Dissolution was chemically controlled and so the rate was very dependent upon temperature and solution potential. Displacement of copper(II) from solution to form copper sulfide was also found to be important.
In addition to the above studies, which relate directly to the oxidative leaching of nickel matte, an investigation of the oxidation of HzS to sulfur in acidic solution was carried out. Sulfer deposition was found to be strongly dependent on substrate and pH. Under some conditions, two types of sulfur were deposited, with the more crystalline sulfer being reduced at the more negative potential.
5
Weatherwax, Trent. "Integrated mining and preconcentration systems for nickel sulfide ores." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/238.
Full textAbstract:
As part of a strategic research initiative at UBC to design and evaluate integrated underground mining and mineral processing systems, work has been done to determine how to utilize the coarse rejects of pre-concentration in the underground environment. An amenability study for nine orebodies from four of Xstrata Nickel’s Ontario operations evaluated both processing and waste disposal methods. Metallurgically the orebodies showed amenability to dense media separation and conductivity sorting. The dense media results showed high mass rejections and high metal recoveries for all nine orebodies. Conductivity sorter results were not as consistent, but still showed good results. Dense media rejects were examined to determine the applicability of their use in rockfills and composite minefills. The geotechnical properties indicated that the rejects would provide a competent material for minefills. The mix designs were examined for both strength and rheological properties and showed that fills utilizing rejects were comparable to fills currently used by industry. Composite fills containing rejects had significantly lower void ratios, decreasing cement requirements for a given strength requirement. Conceptual designs for pre-concentration systems based on the metallurgical, reject characterization, and mix design were developed for each of the four mines in the study. The designs took into consideration the current mining plans.
6
Giovenazzo, Danielle. "Géologie et caractéristiques géochimiques des minéralisations Ni-Cu-EGP de la région de Delta, ceinture de Cape-Smith, Nouveau-Québec /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1991. http://theses.uqac.ca.
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7
Nimah, Ulfa. "Investigation of Secondary Reactions in Bioleaching of Nickel Laterite Ores." Thesis, The University of Sydney, 2019. http://hdl.handle.net/2123/21124.
Full textAbstract:
This thesis investigated the impact of secondary reactions; adsorption and precipitation, on nickel and cobalt recovery from bioleaching of nickel laterite ores. Although bioleaching is considered an ecologically and energy friendly technique to process laterite ores, low recoveries of target metals have inhibited its commercialisation. The secondary reactions occurrence in bioleaching of limonite, fresh and weathered saprolite ores was verified by performing chemical leaching tests using sulphuric and citric acid that would be generated by chemolithotrophs and heterotrophs respectively. The following leaching parameters were kept constant; pulp density at 10 (g/ml)%, particle size of the ore at 64 – 180 µm and stirring speed at 500 rpm. Metal loss was observed typically after 5 – 10 days and it increased as the acid to ore (A/O) ratio was reduced. At the lowest A/O ratio (0.1:1 (g/g)), up to 74% of nickel and 89% of cobalt were lost from target metals leached from saprolites while only 9% of nickel and negligible cobalt were lost from limonite. The mineralogical transformation of the residues resulting from the leaching process contributed to the alteration of the mineral isoelectric point (IEP) and consequently adsorption behaviour. The lower IEP in the saprolite residue (2.5 – 3.5) were attributed to the residual serpentine mineral (3.3) and quartz (2.2). While goethite (6.1 – 6.7) contributed to the higher IEP of the limonite residue (6.9). Systematic tests verified that adsorption can be overcome by maintaining the solution pH below the IEP of residues and adding complexing agent, 15 g/L of citric acid. A simulation of iron precipitation revealed little effect on metals recovery suggesting adsorption was as the primary secondary reaction affecting nickel laterite bioleaching. It is concluded that secondary reactions can have a huge impact on the metal recoveries and controlling its effect is critical in driving the commercialisation of the laterite bioleaching
8
Gaw, Daryl Corbin. "Manganese Removal from Sulfuric Acid Leach Solutions of Nickel Laterite Ores." Thesis, Curtin University, 2020. http://hdl.handle.net/20.500.11937/81026.
Full textAbstract:
An oxidative precipitation technique using potassium permanganate was explored for the removal of manganese from pregnant leach solution (PLS) generated from the pressure acid leaching (PAL) of nickel laterite ores. The results revealed that the right combination of pH and molar ratio is important in order to achieve maximum removal of manganese (II) with minimum nickel (II) and cobalt (II) losses.
9
Chang, Xiangning. "Short term sublethal studies in rats exposed to nickel subsulfide and nickel ore : effects on oxidative damage, antioxidant and detoxicating enzymes /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ55491.pdf.
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10
Thériault, Robert. "Influence de l'assimilation de roches sédimentaires encaissantes sur l'origine des gisements de Cu-Ni-EGP de l'intrusion de Partridge River, complexe de Duluth, Minnesota /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1999. http://theses.uqac.ca.
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11
Heckley, Philip Scott. "Extraction and separation of cobalt from acidic nickel laterite leach solutions using electrostatic pseudo liquid membrane (ESPLIM)." Thesis, Curtin University, 2002. http://hdl.handle.net/20.500.11937/2188.
Full textAbstract:
Approximately 70% of the western world's known nickel reserves are contained in laterite ores, but only 30% of the world's nickel production comes from these ores. This is due to the lack of economically viable technology to extract the nickel from these ores. However, recent advances in pressure acid leaching technology have resulted in new commercial attempts to extract nickel and its valuable by-product, cobalt, from laterite ores. The commissioning of three nickel laterite projects in Western Australia in the late 1990s represents the first of these new generation nickel operations, with several other projects; in Australia and overseas, in various stages of development. Unfortunately, several technical issues have hindered full production in these new refineries. Some of these problems are directly attributable to the mixer-settler contactors used in the solvent extraction process. This has highlighted a need to develop alternative contactors for industrial use. Electrostatic Pseudo Liquid Membrane (ESPLIM) is an alternative, novel technique to conduct the solvent extraction process. It combines the basic principles of solvent extraction, liquid membrane and electrostatic dispersion into a simple, compact reactor that utilises many advantages of each technique. The aim of this study w as to develop a method of extracting and separating cobalt from an acidic nickel laterite leach solution using ESPLIM. Bench scale tests using synthetic and actual leach solutions have shown that: the design and construction materials of the baffle plate and electrodes have a significant effect on the performance of the reactor; an AC power supply provided better droplet dispersion than a DC power supply; an increase in the applied electric field strength above a critical value resulted in a decrease in the aqueous droplet size and an increase in residence tune.These effects increased the extraction efficiency and the concentration of the loaded strip solution. However, further increases in applied electric field strength decreased efficiency due to excessive levels of swelling and leakage; the known extraction isotherms for cobalt and nickel apply in the ESPLIM technique; salts of soluble organic acids influence extraction efficiency by changing the aqueous pH and interfacial tension; the use of ammonia was found to be effective as a replacement for salts of soluble organic acids; the ESPLIM reactor can cope with large changes in the flow rates of both feed and strip solutions. However, an increase in the feed flow rate should be accompanied by a relative increase in the ship flow rate to maintain high extraction efficiencies; the baffle design has a significant impact on the levels of swelling and leakage; provided the electrostatic field strength is maintained and flow rates are increased proportionately to the size of the reactor, no significant scale-up issues were observed, indicating that the data generated in bench scale studies could be applied to plant scale contactors. The optimum conditions, devised as a result of this investigation, to extract cobalt from an acidic nickel laterite leach solution using the ESPLIM technique are as follows: an applied electric field strength of 5.5 kV/cm. a raffinate pH of 5.5, a solvent containing 10% Cyanex 272 with 5% TBP in Solvent HF diluent, a feed to strip flow ratio of approximately 5 and a 1 M H[subscript]2S0[subscript]4 strip solution. At these conditions, almost complete cobalt extraction is achieved after only two extraction stages. A comparable extraction using conventional mixer-settlers could only be achieved after five stages.
12
Bandyayera, Daniel. "Formation des latérites nickélifères et mode de distribution des éléments du groupe du platine dans les profils latéritiques du complexe de Musongati, Burundi /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1997. http://theses.uqac.ca.
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13
Tremblay, Christian. "Les éléments du groupe du Platine dans le dyke de Méquillon ceinture de Cape-Smith, Nouveau-Québec /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1990. http://theses.uqac.ca.
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14
Lipp, Ulrich, and Siegfried Flach. "Wismut-, Kobalt-, Nickel- und Silbererze im Nordteil des Schneeberger Lagerstättenbezirkes." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-79017.
Full textAbstract:
Der Schneeberger Lagerstättenbezirk weist eine über 500 Jahre alte bergbauliche Geschichte auf. In dem Mitte des letzten Jahrhunderts aufgeschlossenen Lagerstättenteil Schlema-Alberoda befasst sich vorliegende Monographie mit den Bi-Co-Ni- und Ag-erzführenden Gängen, die die Schichtenfolge der Lößnitz-Zwönitzer Mulde durchschlagen. Die Gänge sind an die Hüllgesteine im nordwestlichen Teil des Kontakthofes zum Granitmassiv von Aue gebunden. Ihre Zonalität bedingt eine Zonalität der Spaltenbildung, die sich in einer unterschiedlichen Intensität und einer abnehmenden Anzahl von Gangsystemen und Gängen in den einzelnen Zonen des Kontakthofes mit fortschreitender Entfernung von der Granitoberfläche äußert. In den erzgebirgisch ausgerichteten Störungen und den herzyn streichenden Erzgänge haben die zwei Hauptrichtungen unterschiedlichen Einfluss auf die Lokalisation der Bi-Co-Ni- und Ag-Vererzung. Die ältesten Ausscheidungen bilden die Paragenesen der tiefpneumatolytischen Quarz-Wolframit- und der hydrothermalen Quarz-Scheelit-Abfolge, an die sich die Mineralisation der Quarz-Sulfid-Gänge anschließen. Der nachfolgende, saxonische Subzyklus weist als älteste Mineralbildungen Paragenesen der Quarz-Kalzit-Pechblende-Gänge auf, denen die Paragenesen der Dolomit-Gänge folgen, die die vorangegangenen Paragenesen metasomatisch überprägen und pseudomorphosieren. Ihnen schließen sich die Paragenesen der Arsenid-Gänge an. Dagegen fehlen Fluorit-Baryt-Gänge nahezu völlig. Dem alpidischen Subzyklus werden die Paragenesen der Arsen-Silbersulfid- und der Eisen-Mangan-Gänge zugeordnet. Die Mineralisation weist sowohl eine ausgeprägte polyaszendente Zonalität, mit Bindung der einzelnen Gangformationen an bestimmte Zonen und Bereiche des Kontakthofes, daneben aber auch monoaszendente Zonalitäten auf. Die äußere Kontur der Vererzung der biconi-Formation folgt in einem steilen Abfall der Granitoberfläche und fällt etwa gleichartig wie die Grenze des äußeren Kontakthofes ein. Mit fortschreitender Teufe zeigen im Allgemeinen Co und Bi eine Zunahme und Ni eine Abnahme mit Annäherung an die Granitoberfläche. Die zonale Verbreitung der Paragenesen der ags-Formation beschränkt sich hauptsächlich auf den äußeren Kontakthof und wird vor allem von der Verbreitung der gediegen Silber führenden Paragenesen beeinflusst. Für die einzelnen Paragenesengruppen der biconi-Formation lassen sich Reihen der ?Produktivität\" der Nebengesteine ermitteln und an zahlreichen Gangbeispielen näher erläutern. Die Herkunft von Co und Ni aus den Metabasiten lässt sich sowohl auf gangstatistischem Wege als auch nach dem Umfang der gewonnenen Metallmenge belegen. Die Elemente Wismut und Silber werden aus hydrothermalen Lösungen abgeleitet, die einer simatisch-juvenilen Magmenquelle entstammen. Als Lieferant von Arsen werden dagegen bituminöse und phyllitische Gesteine angesehen. Unter den tektonisch-strukturellen Faktoren, die die Lokalisation der Bi-Co-Ni- und Ag-Vererzung beeinflussen, besitzen Störungen den wichtigsten Einfluss. Keinen Einfluss auf die Lokalisation der Vererzung weisen Gangkreuze auf. Einen ausfällenden Einfluss auf die Co-Ni-Arsenid-Vererzung der eba-Abfolge besitzen Gangscharungen unterschiedlicher Strukturordnung. Die polygenetische Ableitung der Bi-Co-Ni- und Ag-Vererzung schließt eine mögliche Beteiligung vadoser Wässer an der Bildung der biconi-Formation nicht aus. Die gewonnenen Ergebnisse über die auf die Lokalisation der Vererzung der biconi- und der ags-Formation einwirkenden erzkontrollierenden Faktoren gestatten eingeschränkt Voraussagen über das Auftreten neuer unbekannter Bi-Co-Ni-Erzfälle in noch nicht aufgeschlossenen Feldesteilen.
15
Lipp, Ulrich, and Siegfried Flach. "Wismut-, Kobalt-, Nickel- und Silbererze im Nordteil des Schneeberger Lagerstättenbezirkes." Sächsisches Landesamt für Umwelt, Landwirtschaft und Geologie, 2003. https://slub.qucosa.de/id/qucosa%3A1649.
Full textAbstract:
Der Schneeberger Lagerstättenbezirk weist eine über 500 Jahre alte bergbauliche Geschichte auf. In dem Mitte des letzten Jahrhunderts aufgeschlossenen Lagerstättenteil Schlema-Alberoda befasst sich vorliegende Monographie mit den Bi-Co-Ni- und Ag-erzführenden Gängen, die die Schichtenfolge der Lößnitz-Zwönitzer Mulde durchschlagen. Die Gänge sind an die Hüllgesteine im nordwestlichen Teil des Kontakthofes zum Granitmassiv von Aue gebunden. Ihre Zonalität bedingt eine Zonalität der Spaltenbildung, die sich in einer unterschiedlichen Intensität und einer abnehmenden Anzahl von Gangsystemen und Gängen in den einzelnen Zonen des Kontakthofes mit fortschreitender Entfernung von der Granitoberfläche äußert. In den erzgebirgisch ausgerichteten Störungen und den herzyn streichenden Erzgänge haben die zwei Hauptrichtungen unterschiedlichen Einfluss auf die Lokalisation der Bi-Co-Ni- und Ag-Vererzung. Die ältesten Ausscheidungen bilden die Paragenesen der tiefpneumatolytischen Quarz-Wolframit- und der hydrothermalen Quarz-Scheelit-Abfolge, an die sich die Mineralisation der Quarz-Sulfid-Gänge anschließen. Der nachfolgende, saxonische Subzyklus weist als älteste Mineralbildungen Paragenesen der Quarz-Kalzit-Pechblende-Gänge auf, denen die Paragenesen der Dolomit-Gänge folgen, die die vorangegangenen Paragenesen metasomatisch überprägen und pseudomorphosieren. Ihnen schließen sich die Paragenesen der Arsenid-Gänge an. Dagegen fehlen Fluorit-Baryt-Gänge nahezu völlig. Dem alpidischen Subzyklus werden die Paragenesen der Arsen-Silbersulfid- und der Eisen-Mangan-Gänge zugeordnet. Die Mineralisation weist sowohl eine ausgeprägte polyaszendente Zonalität, mit Bindung der einzelnen Gangformationen an bestimmte Zonen und Bereiche des Kontakthofes, daneben aber auch monoaszendente Zonalitäten auf. Die äußere Kontur der Vererzung der biconi-Formation folgt in einem steilen Abfall der Granitoberfläche und fällt etwa gleichartig wie die Grenze des äußeren Kontakthofes ein. Mit fortschreitender Teufe zeigen im Allgemeinen Co und Bi eine Zunahme und Ni eine Abnahme mit Annäherung an die Granitoberfläche. Die zonale Verbreitung der Paragenesen der ags-Formation beschränkt sich hauptsächlich auf den äußeren Kontakthof und wird vor allem von der Verbreitung der gediegen Silber führenden Paragenesen beeinflusst. Für die einzelnen Paragenesengruppen der biconi-Formation lassen sich Reihen der ?Produktivität\' der Nebengesteine ermitteln und an zahlreichen Gangbeispielen näher erläutern. Die Herkunft von Co und Ni aus den Metabasiten lässt sich sowohl auf gangstatistischem Wege als auch nach dem Umfang der gewonnenen Metallmenge belegen. Die Elemente Wismut und Silber werden aus hydrothermalen Lösungen abgeleitet, die einer simatisch-juvenilen Magmenquelle entstammen. Als Lieferant von Arsen werden dagegen bituminöse und phyllitische Gesteine angesehen. Unter den tektonisch-strukturellen Faktoren, die die Lokalisation der Bi-Co-Ni- und Ag-Vererzung beeinflussen, besitzen Störungen den wichtigsten Einfluss. Keinen Einfluss auf die Lokalisation der Vererzung weisen Gangkreuze auf. Einen ausfällenden Einfluss auf die Co-Ni-Arsenid-Vererzung der eba-Abfolge besitzen Gangscharungen unterschiedlicher Strukturordnung. Die polygenetische Ableitung der Bi-Co-Ni- und Ag-Vererzung schließt eine mögliche Beteiligung vadoser Wässer an der Bildung der biconi-Formation nicht aus. Die gewonnenen Ergebnisse über die auf die Lokalisation der Vererzung der biconi- und der ags-Formation einwirkenden erzkontrollierenden Faktoren gestatten eingeschränkt Voraussagen über das Auftreten neuer unbekannter Bi-Co-Ni-Erzfälle in noch nicht aufgeschlossenen Feldesteilen.
16
Ozdemir, Veysel. "Hydrometallurgical Extraction Of Nickel And Cobalt From Caldag Lateritic Ore." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607777/index.pdf.
Full textAbstract:
In this study, an attempt has been made to hydrometallurgical extraction of cobalt and nickel by atmospheric pressure sulphuric acid leaching and a pug-roast-leach process using two stage roasting for lateritic ore. The ore used in the study was obtained from Çaldag Lateritic Ore, Manisa, Turkey. The metal contents of the ore are 2.1 % Ni, 0.12 % Co, 32.45 % Fe, 1.01 % Mn, 2.58 % Cr, 0.78 % Mg and 1.01 % Al. The reserve of lateritic ore deposit is approximately 40 million tonnes. In the study, first sulphuric acid leaching was applied at atmospheric pressure for leaching the Ç
aldag lateritic ore. The effect of various parameters, such as leaching time, leaching temperature, particle size, pulp density and acid strength on Ni and Co extractions were determined. By leaching at 80oC for 40 wt % H2SO4 addition of ore, 1/3 pulp density, Ni and Co extractions were found 44.49 % and 53.03 % respectively, yielded a pregnant solution containing 3.11 g/L Ni and 0.12 g/L Co. But the result of atmospheric pressure sulphuric acid leaching was considered insufficient from the recovery point of view. In the pug-roast-leach process, which is consisted of a two stage roasting followed by water leaching, decomposition temperature differences of sulphates of cobalt, nickel and iron are exploited. In this process, amount of acid, sulphatization and decomposition temperature, sulphatization and decomposition time, leaching temperature and time, solid/liquid ratio, and the effect of water addition during pugging were optimized. Under the optimized conditions (sulphuric acid: 25 wt % of ore
moisture: 20 wt % of ore
sulphatization temperature: 450oC
sulphatization time: 30 minutes
decomposition temperature: 700oC
decomposition time: 60 minutes
leaching temperature: 70oC
leaching time: 30 minutes and solid-liquid ratio: 1/4 by weight), Co and Ni extractions were found 91.4 and 84.4 percent, respectively. A pregnant solution containing 3.084 g/L Ni and 0.185 g/L Co was obtained. These results were considered sufficient for the leaching of lateritic nickel ores.
17
Heckley, Philip Scott. "Extraction and separation of cobalt from acidic nickel laterite leach solutions using electrostatic pseudo liquid membrane (ESPLIM)." Curtin University of Technology, Western Australian School of Mines, 2002. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=14124.
Full textAbstract:
Approximately 70% of the western world's known nickel reserves are contained in laterite ores, but only 30% of the world's nickel production comes from these ores. This is due to the lack of economically viable technology to extract the nickel from these ores. However, recent advances in pressure acid leaching technology have resulted in new commercial attempts to extract nickel and its valuable by-product, cobalt, from laterite ores. The commissioning of three nickel laterite projects in Western Australia in the late 1990s represents the first of these new generation nickel operations, with several other projects; in Australia and overseas, in various stages of development. Unfortunately, several technical issues have hindered full production in these new refineries. Some of these problems are directly attributable to the mixer-settler contactors used in the solvent extraction process. This has highlighted a need to develop alternative contactors for industrial use. Electrostatic Pseudo Liquid Membrane (ESPLIM) is an alternative, novel technique to conduct the solvent extraction process. It combines the basic principles of solvent extraction, liquid membrane and electrostatic dispersion into a simple, compact reactor that utilises many advantages of each technique. The aim of this study w as to develop a method of extracting and separating cobalt from an acidic nickel laterite leach solution using ESPLIM. Bench scale tests using synthetic and actual leach solutions have shown that: the design and construction materials of the baffle plate and electrodes have a significant effect on the performance of the reactor; an AC power supply provided better droplet dispersion than a DC power supply; an increase in the applied electric field strength above a critical value resulted in a decrease in the aqueous droplet size and an increase in residence tune.These effects increased the extraction efficiency and the concentration of the loaded strip solution. However, further increases in applied electric field strength decreased efficiency due to excessive levels of swelling and leakage; the known extraction isotherms for cobalt and nickel apply in the ESPLIM technique; salts of soluble organic acids influence extraction efficiency by changing the aqueous pH and interfacial tension; the use of ammonia was found to be effective as a replacement for salts of soluble organic acids; the ESPLIM reactor can cope with large changes in the flow rates of both feed and strip solutions. However, an increase in the feed flow rate should be accompanied by a relative increase in the ship flow rate to maintain high extraction efficiencies; the baffle design has a significant impact on the levels of swelling and leakage; provided the electrostatic field strength is maintained and flow rates are increased proportionately to the size of the reactor, no significant scale-up issues were observed, indicating that the data generated in bench scale studies could be applied to plant scale contactors. The optimum conditions, devised as a result of this investigation, to extract cobalt from an acidic nickel laterite leach solution using the ESPLIM technique are as follows: an applied electric field strength of 5.5 kV/cm. a raffinate pH of 5.5, a solvent containing 10% Cyanex 272 with 5% TBP in Solvent HF diluent, a feed to strip flow ratio of approximately 5 and a 1 M H[subscript]2S0[subscript]4 strip solution. At these conditions, almost complete cobalt extraction is achieved after only two extraction stages. A comparable extraction using conventional mixer-settlers could only be achieved after five stages.
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Sibbick, Steven John Norman. "The distribution and behaviour of gold in soils in the vicinity of gold mineralization, Nickel Plate mine, southern British Columbia." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28862.
Full textAbstract:
Sampling of soils and till are conventional methods of gold exploration in glaciated regions. However, the exact nature of the residence sites and behaviour of gold within soil and till are poorly known. A gold dispersion train extending from the Nickel Plate mine, Hedley, southwest British Columbia, was investigated in order to determine the distribution and behaviour of gold within soils developed from till.
Three hundred and twelve soil, till and humus samples (representing LFH, A, B and C horizons) were collected from fifty-two soil pits and thirty-four roadcut locations within the dispersion train. Soil and till samples were sieved into four size fractions; the resultant -212 micron (-70 mesh) fraction of each sample was analysed for Au by FA-AAS. Humus samples were ground to -100 micron powder and analysed for Au by INAA. Based on the analytical results, each LFH, A, B and C horizon was subdivided into anomalous and background populations.
Detailed size and density fraction analysis was carried out on soil profiles reflecting anomalous and background populations, and a mixed group of samples representing the overlap between both populations. Samples were sieved to six size fractions; three of the size fractions (-420+212, -212+106, -106+53 microns) were separated into two density fractions using methylene iodide and analysed for Au by FA-AAS. The Au content of the -53 micron fraction was analysed by FA-AAS and cyanide extraction - AAS.
Results indicate that the Au content of soil profiles increase with depth while decreasing with distance from the minesite. Heavy mineral concentrates and the light mineral fraction Au abundances reveal that dilution by a factor of 3.5 occurs within the till over a distance of 800 metres. However, free gold within the heavy mineral fraction is both diluted and comminuted with distance. Recombination of size and density fractions indicate that the Au contents of each size fraction are equivalent; variation in Au abundance is not observed with a change in grain size. Seventy percent of the Au in the -53 micron fraction occurs as free gold.
Chemical activity has not altered the composition of gold grains within the soil profiles. Compositional and morphological differences between gold grains are not indicative of glacial transport distance or location within the soil profile. Relative abundances of gold grains between sample locations can be used as an indicator of proximity to the minesite. The sampling medium with the best sample representivity and contrast between anomalous and background populations is the -53 micron (-270 mesh) fraction of the C horizon. Geochemical soil sampling programs in the vicinity of the Nickel Plate mine should collect a minimum mass of 370 grams of -2000 micron (-2 mm) soil fraction in order to obtain 30 grams of the -53 micron fraction.Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate
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Azevedo, Luiz Otavio Roffee. "Infra-Red Spectrophotometry and X-Ray Diffractometry as Tools in the Study of Nickel Laterites." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/231213.
Full textAbstract:
Nickel silicate laterite deposits developed on ultra-mafic rocks are similar in many general respects but they vary considerably in detail. The mineralogy of these surficial deposits is very complex and difficult to determine because of the fine grained nature and solid solution characteristics of the hydrous secondary minerals and because many of the phases are actually mineraloids that are poorly ordered or amorphous. To try some new approaches toward clarification of these phases, 24 samples from New Caledonia and Puerto Rico ranging from the ophiolite-ultramafic olivine-pyroxene-chromite-serpentine substrate rocks upward through intermediate phases of weathering to the final oxide -hydroxide iron cap phase were analyzed with the infrared spectrophotometer (IR -10) and with the automated X –ray diffractometer. Four limonite samples were also mineralogically analyzed. Goethite, secondary quartz, cryptomelane, hematite, chromite, talc, thuringite, and garnierite have been identified in various samples as weathering profile products.
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Mehlape, Mofuti Amos. "Computational modeling studies of cobalt pentlandite (Co₉S₈)." Thesis, University of Limpopo (Turfloop Campus), 2013. http://hdl.handle.net/10386/984.
Full textAbstract:
Thesis (Ph.D. (Physics)) --University of Limpopo, 2013The intention of the current study is to investigate structure, ion transport and reactivity of various forms of the cobalt pentlandite, Co9S8, at different temperatures using atomistic simulation methods with the support of electronic structure calculations. The first interatomic potentials of Co9S8 were derived with input data as structure and elastic properties from experiment and electronic structure calculations respectively. The potentials were validated by running energy minimization and molecular dynamics calculations. Structure, elastic properties and phonon spectra were well reproduced, together with the complex high temperature transformations and melting of Co9S8 as deduced from crystal structure, radial distribution functions, density profiles and diffusion coefficients. Amongst the high symmetry surfaces {111}, {101} and {101} atomistic surface energy calculations proposed the {111} surface of Co9S8 as the most stable in agreement with experimental morphologies, and water adsorption energies on the such surfaces which mostly agreed with those from electronic structure calculations. The structural and ion transport variations with temperature were investigated and predicted surface melting at lower temperatures than the bulk. The effects of hydration on the surfaces at low and high temperatures were also studied. The structural and ion transport properties of Co9S8 nanoparticles of varying sizes, covered by high symmetry surfaces {111}, {101} and {100} were predicted using molecular dynamics method based on our derived interatomic potentials. The structural and ion transport properties of Co9S8 nanoparticles of varying sizes, covered by high symmetry surfaces {111}, {101} and {100} were predicted using molecular dynamics method based on our derived interatomic potentials. Generally for {111}, {101} nanoparticles, high temperature transitions were abrupt for smaller nanoparticles and these tended to disintegrate and form voids. However, for larger nanoparticles the transitions were more gradual. Transitions in the {100} bound nanoparticles were less dramatic for all sizes and the formation of voids was reduced at high temperatures. Generally, the melting temperatures of different sizes of nanoparticles increases with the particle size hence approach the bulk limit. The interaction of nanoparticles with water was investigated.
Anglo Platinum, National Research Foundation (South Africa), and The Royal Society (UK)
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Onal, Mehmet Ali Recai. "Pressure Leaching Of Caldag Lateritic Nickel Ore." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615480/index.pdf.
Full textAbstract:
The purpose of this study was to investigate the process optimization of combined high pressure acid leaching (HPAL) and mixed hydroxide precipitation (MHP) route for the extraction of nickel and cobalt from Çaldag lateritic nickel ore. In order to extract nickel and cobalt values into pregnant leach solution (PLS), several process parameters of HPAL including acid load, temperature, leaching duration and particle size were investigated in comparative manner at constant solid concentration and agitation speed. After HPAL trials, it has been found that more than one combination of parameters offered higher than 90% extraction efficiencies for both nickel and cobalt. Among them, 0.325 kg/kg acid load, 250°
C, 1 hour duration and 100% -1 mm particle size was selected as the optimum conditions with 94.1% Ni and 94.0% Co extractions. A stock of PLS was prepared under the stated conditions that was treated by downstream operations in order to obtain MHP. Initially by two-stage iron removal of downstream operations major impurities iron, chromium and aluminum were nearly completely removed with acceptable nickel and cobalt losses from PLS. Then, the nickel and cobalt were precipitated by two-stage mixed hydroxide precipitation. In the first step of MHP, the optimum conditions were chosen as pH=7.10, 60°
C and 1 hour duration. The intermediate product obtained at these conditions contained 44.3% Ni, 3.01% Co with 3.06% Mn contamination. In summary, it was found that Ç
aldag nickel laterite ore was readily leachable under HPAL conditions and PLS obtained was easily treatable in order to produce saleable MHP.
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Sabau, Adrian I. "Laboratory studies on magnetoflotation of Falconbridge nickel ore." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0001/MQ31465.pdf.
Full text
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Kanhai, Todd M. "The effect of shotcrete on the flotation nickel recoveries and selectivities of Falconbridge nickel-copper ore." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0009/MQ61272.pdf.
Full text
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Cameron, Rory. "Bioleaching of low-grade nickel sulphide ore at elevated pH." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19784.
Full textAbstract:
This thesis examines the bioleaching of six different Canadian nickel sulphide ores at pH levels above what is generally considered optimum (~ 2). The majority of work discussed in this thesis was conducted with a low-grade metamorphosed ultramafic nickel sulphide ore from Manitoba, Canada (Ore 3), which is not currently exploitable with conventional technologies. The ore contains 21% magnesium and 0.3% nickel. Nickel is the only significant metal value, and is present primarily as pentlandite. A substantial fraction of the magnesium is present as the serpentine mineral lizardite, making processing difficult with conventional pyro- and biohydrometallurgical techniques. The work with this ore has two equally important objectives: to minimize magnesium mobilization and to obtain an acceptable level of nickel extraction. Batch stirred-tank bioleaching experiments were conducted with finely ground ore ( 147 µm) with temperature and pH control. The first phase of experimentation examined the effect of pH (2 to 6) at 30 °C, and the second phase examined all combinations of three pH levels (3, 4 and 5) and five temperatures (5, 15, 22.5, 30, and 45 °C).
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Uddin, Salah. "Surface charge characterization and flotation of an ultramafic nickel ore." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107688.
Full textAbstract:
AbstractAbout 300 million tonnes of inferred Ni resource in ultramafic hosted rocks is present in 'Thompson Nickel Belt' in north central Manitoba. The processing challenges result from electrostatic interaction between pentlandite (the main Ni-mineral) and serpentine (the main gangue and one of the MgO minerals). As a contribution to meeting the challenge, the thesis examines the role of particle and bubble surface charge and the effect of fibre disintegration on flotation behavior of an ultramafic Ni ore sample. For surface charge characterization the sedimentation potential technique was used. A novel integrated device was developed to measure sedimentation potential, conductivity and pH simultaneously. Maxwell's model was used to calculate volume fraction of dispersed phase from conductivity, and zeta potential, when appropriate, was calculated from the Smoluchowski equation. The technique was validated by showing good agreement with iso-electric point for alumina, silica and bubble suspensions with electrophoresis measurements. The technique was extended to characterize mixed minerals including ultramafic ore, and bubbles in the presence of particles. The results provided some evidence of metal ion adsorption on particles and the possibility of non-hydrophobic particle attachment to bubbles. The latter was reinforced by visualization studies of a pendant bubble exposed to particle suspensions.A novel fibre disintegration strategy was devised combining both chemical (acid) and physical (grinding) treatment based on work to enhance carbon dioxide uptake by serpentine. Using HCl, subsequent conventional flotation (amyl xanthate, soda ash and MIBC) gave significantly improved results over the untreated ore. Using H2SO4, arguably the practical option led to flotation without collector due to elemental sulphur formation on pentlandite, and without frother due to high ionic strength solutions. Improved Ni grade-recovery with higher MgO mineral rejection was achieved. Structural changes in the fibres were followed using various spectroscopic techniques and a mechanism of fibre disintegration suggested.Environ 300 millions de tonnes de ressources inférées de Ni ultramafiques hébergé est présent dans 'ceinture nickélifère de Thompson' dans le centre-nord du Manitoba. Le traitement des défis résultant de l'interaction électrostatique entre pentlandite (le principal Ni-minéraux) et la serpentine. En tant que contribution à relever le défi, la thèse examine le rôle des particules et la charge de surface des bulles et l'effet de la désintégration des fibres sur le comportement de flottaison d'un échantillon de minerai de nickel ultramafiques. Pour la caractérisation de charge de surface de la technique de sédimentation potentielle a été utilisée. Un nouveau dispositif intégré a été développé pour mesurer le potentiel de sédimentation, la conductivité et le pH simultanément. Le modèle de Maxwell a été utilisée pour calculer la fraction volumique de phase dispersée de la conductivité, et le potentiel zêta, le cas échéant, a été calculée à partir de l'équation de Smoluchowski. La technique a été validée en montrant un bon accord avec l'iso-électrique de point pour les suspensions d'alumine, de silice et de bulles avec des mesures d'électrophorèse. La technique a été étendue afin de caractériser les minéraux mélangés, y compris de minerai ultramafiques, et des bulles dans la présence de particules. Les résultats ont fourni des preuves de ion métallique adsorption sur les particules et la possibilité de l'attachement des particules non-hydrophobe à bulles. Ce dernier a été renforcée par des études de la visualisation d'une bulle Pendentif exposés à des suspensions de particules.Une stratégie nouvelle fibre de désintégration a été conçu combinant à la fois chimique (acide) et physiques (broyage) un traitement basé sur le travail pour améliorer l'absorption du dioxyde de carbone par la serpentine. En utilisant HCl, à la suite de flottation conventionnelle (amyl xanthate, la cendre de soude et de MIBC) a donné des résultats nettement améliorés au cours des minerais non traités. Utiliser H2SO4, sans doute l'option la pratique conduit à de flottaison sans collecteur due à la formation du soufre élémentaire sur la pentlandite, et sans buse due à des solutions à haute force ionique. Amélioration de qualité Ni-reprise avec le rejet supérieur de MgO de a été atteint. Les changements structurels dans les fibres ont été suivis en utilisant diverses techniques de spectroscopie et d'un mécanisme de désintégration de fibre suggéré.
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Field, Karen Louise. "Atmospheric leaching of a saprolytic nickel laterite ore in chloride solutions." Master's thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/5612.
Full text
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Goveli, Ahmet. "Nickel Extraction From Gordes Laterites By Hydrochloric Acid Leaching." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607738/index.pdf.
Full textAbstract:
Leaching is the most widely used process for extraction of nickel metal from lateritic ores.
In this study, nickel extraction from Manisa-Gördes region laterites by hydrochloric acid leaching is aimed. The mineralogical analysis of sample showed that hematite, goethite, dolomite, quartz and smectite are the main minerals in the ore. Attrition scrubbing, cycloning and magnetic separation with permroll were used as preconcentration processes but results were unsatisfactory. HCl leaching experiments were conducted both at room temperature and at elevated temperatures. The effects of various parameters such as leaching duration, particle size, concentration of HCl, pulp density, Cl- concentration and temperature on nickel recovery were examined. The results showed that under the optimised leaching conditions (particle size: 100 % -1 mm, HCl concentration: 3 N, leaching duration: 3 hours, leaching temperature: 100 oC, pulp density: 1/30 solid to liquid ratio by volume) it was possible to extract 87.26 % of nickel in the ore.
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Pillay, Keshree. "Mineralogical effects on the dense medium separation of low grade nickel sulfide ore." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/13751.
Full textAbstract:
Dense medium separation (DMS) is a method often used to upgrade base metal sulfide (BMS) ores before their main processing stage, with varying results achieved for different ore types. The process makes use of the density differences between the BMS minerals and the lower density silicate/carbonate gangue minerals, using a separating medium of density between the two ore components. The separation is accelerated using a dense medium cyclone (DMC) to form two products: overflow (tailings) and underflow (concentrate). The purpose of DMS is to reject large quantities of gangue upfront, resulting in reduced time, energy and costs associated with processes such as milling and flotation. Preconcentration of ores using physical methods such as DMS is becoming an important consideration as lower grade ores are mined, to increase the feasibility of mining such ores. Two nickel sulfide deposits were chosen as case studies in order to understand differences in DMS efficiency for different ores. The first is the Main Mineralised Zone (MMZ) of the Nkomati Nickel deposit in Mpumalanga, South Africa, which is part of the Uitkomst Complex. The Phoenix deposit is also considered, and forms part of the Tati greenstone belt in eastern Botswana. Both deposits are magmatic Cu-Ni-PGE (platinum group element) deposits with similar sulfide mineralogy and pentlandite as the main nickel host. A process mineralogy approach was used to evaluate samples of both ores, describing the differences in the mineralogical properties within the overflow and underflow of each ore in order to understand the extent to which individual properties affect the separation.
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Ugwu, Ifeoma Mary. "Sorption of nickel and cobalt on goethite with application to laterite ore formation." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.691177.
Full textAbstract:
Nickel extracting industries have been facing challenges reflecting, inter alia, low recoveries of Ni and Co, high acid consumption and inadequate knowledge of dissolution kinetics. In oxic laterite, Ni is mostly associated with goethite. Consequently, for effective extraction of Ni and Co from oxic Ni laterites, a clear understanding of their chemistry, mineralogy and mechanism of sorption in goc;!thite during laterite ore formation is essential. The result from experiment of Ni sorption on goethite revealed that at surface loadings of 0.003 to 0.2 wt. % Ni, only the >Fe(OH)2Ni complex was needed to, fit the data whereas both >Fe(OH)2Ni and (FeOH)2Ni complexes were invoked to fit surface loadings of >0.2 to 0.35 wt. % Ni. At 0.75 wt. % Ni and above, however, the polynuclear complex (FeOH)3Nh was required to fit the data. Similar results were obtained for Co sorption and co-sorption of Ni and Co on goethite. EXAFS results support the existence of Ni surface precipitate or extended polynuclear Ni complex in the Ni-sorbed goethite and Ni laterite. In all the samples, Ni and Co dissolve incongruently with iron. However, there exist disparities in their dissolution and desorption kinetics as a function of aging and concentration, which indicate differences in chemical structure. Modelling of Ni laterite using PHREEQC and equilibrium constants obtained from EQLFOR provides information on the processes of Ni laterite formation and the zones of supergene Ni enrichment as well as prediction of the weathering profile. The solubility product (Ksp) of Ni or Co substituted goethite increases with increasing metal substitution. Similar results were obtained for bi-metal substituted goethite. In general, leaching with dilut~ 2.75 M aqua regia is best for Ni laterites formed at low loading as well as those formed via surface precipitation with Fe content less than 33 wt. % Fe whereas 2.75 M HCI is effective for those formed at high loading containing> 33 wt.% iron.
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Franchuk, Anatoliy. "HIGH TENOR NI-PGE SULFIDE MINERALIZATION OF THE SOUTH MANASAN ULTRAMAFIC INTRUSION, THOMPSON NICKEL BELT, MANITOBA." Thesis, Laurentian University of Sudbury, 2014. https://zone.biblio.laurentian.ca/dspace/handle/10219/2195.
Full textAbstract:
The South Manasan ultramafic intrusion (ca. 1880 Ma) located in the Early Proterozoic
Thompson Nickel Belt (TNB) contains Ni and platinum group element (PGE) mineralization
hosted by disseminated sulfide. Whole-rock Ni values range from 0.3 to 1.7 wt. % and total
precious metals (TPMs) range from 0 to 1.3 ppm Pt + Pd + Au and equate to tenor values (i.e.,
metal in 100% sulfide) of 11-39 wt. % Ni and 8-27 ppm TPMs. The South Manasan intrusion is
a steeply dipping sill-like body with a boudinaged outline having a strike length of
approximately 1200 m, average width of 125 m and a minimum depth extent of 1000 m. The
intrusion is composed of approximately 25% fresh dunite, 50% serpentine altered dunite and
25% tectonized and carbonate altered dunite. The most intense alteration is found near the
intrusion’s margin where it is in contact with metasedimentary rocks of the Pipe Formation, part
of the surrounding Ospwagan Group. In fresh dunite the sulfide assemblage characterized by an
intercumulate texture is dominated by pentlandite with accessory pyrite; the latter having a
symplectic-like texture. The pentlandite-pyrite assemblage in the serpentinized dunite, although
still characterized overall by an intercumlate-texture, has well developed platy intergrowths with
chlorite and serpentine. In the most intensely modified unit (the carbonate altered dunite) the
sulfide assemblage consists primarily of pyrrhotite and pentlandite.
Whole-rock geochemical data (n=360), modal mineralogy and mineral chemistry
obtained on representative drill core throughout the South Manasan intrusion have been used to
establish a type section in order to evaluate the relative roles of primary magmatic versus
secondary (i.e., serpentinization, carbonate alteration and deformation) processes. These data
indicate that the primary silicate-sulfide assemblage was systematically modified during : serpentinization, carbonate alteration and deformation of the South Manasan intrusion such that a
sequence of primary versus secondary events can be established. Intrusion of the original
komatiitic magma and formation of the South Manasan intrusion took place at a shallow level
into consolidated Ospwagan Group sediments with subsequent contamination of this melt with
crustal S. This triggered sulfide saturation and generation of an immiscible sulfide melt.
Calculated Ni and TPM tenor values constrain the R factor to between 500 and 2500. The early
crystallization of olivine inhibited the sulfide melt from settling to the bottom of the magma
column and as a consequence, the sulfides now have a primary interstitial magmatic texture. The
current sulfide association dominated by pentlandite>>pyrite>chalcopyrite has a mineral
paragenesis that is consistent with subsolidus re-equilibration of a primary pentlanditepyrrhotite-
chalcopyrite assemblage. The subsequent processes of serpentinization, deformation
and carbonate alteration resulted in modifying the primary sulfide assemblages and their textures
(i.e., to platy habits), but did not greatly alter the bulk composition, in particular metal contents,
except for addition of volatiles (H2O, CO2).
It is concluded therefore that the enrichment of the sulfide assemblage at South Manasan
in Ni and PGEs is a consequence of a primary magmatic process involving high R factor and that
the effects of later overprinting processes (alteration, deformation) are not responsible for the
presently observed high-tenor sulfide association.
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Kilickaplan, Isil. "Effect of pulp rheology on flotation : the nickel sulfide ore with asbestos gangue system." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/12765.
Full textAbstract:
Pulp rheology is a sensitive indicator of the state of aggregation/dispersion of mineral particles. In this study, possible correlation between the rheological properties of flotation pulp and the flotation response was investigated through a series of rheological and batch flotation tests.
The nickel-sulfide ore from the Mt. Keith plant (Western Australia) was used for the tests. It is a low-grade nickel sulfide ore which is characterized by complex mineralogical composition with a large content of serpentine minerals.
The experimental program included agglomerate flotation tests and rheological tests with the use of a slurry produced by grinding the nickel-sulfide ore. In order to see the effect of solids content on flotation, a series of tests were performed at various pulp densities in the absence and presence of oil in both conditioning and flotation stages. The agglomerate flotation and rheological tests were repeated with dispersants in order to investigate the correlation between degree of agglomeration/dispersion and flotation response.
The agglomerate flotation tests conducted at various solids content in the flotation stage revealed that the fastest flotation rate was observed at the lowest solids content. The entrainment was found to increase with increasing solids content due to elevated pulp viscosity. The “boiling” was observed in the flotation cell in the tests at a high pulp density, the effect likely associated with a high pulp viscosity. High pulp viscosity is clearly increasing the size of bubbles in the flotation system. In line with this the high recoveries by entrainment are observed in the tests at high pulp density. Under such conditions the concentrate grade was low since a large proportion of the nickel recovery resulted from entrainment. In distilled water the use of a dispersant improved considerably flotation performance.
The presence of chrysotile in the system strongly affects the pulp viscosity. In the tests with pure chrysotile the pulp with a solids content of around 0.8% by volume is close to the critical packing fraction. However, in the tests with the nickel ore containing more than 80% of chrysotile the viscosity is still far from the critical packing even at 7.6 % solids content by volume. This shows a very beneficial dilution effect; the presence of other non fibrous minerals dramatically decreases the viscosity of the chrysotile suspensions. Without such minerals processing of this ore would have been entirely impossible.
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Pappas, Adlerburg Nickolas T. "To Make Iron of Iron : A Comprehensive Analytical Study of Spade Shaped Iron Bars." Thesis, Stockholms universitet, Arkeologiska forskningslaboratoriet, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-144383.
Full textAbstract:
This thesis aims to provide adequate analytical information on the spade shaped iron bars of Norrland and central Sweden. While their significance has been thoroughly debated for decades, analytical research on them has been confined to cases of single artefacts or theoretical interpretations of their value, meaning and origin. In this study a comprehensive approach is taken into consideration. Based on X-Ray fluorescence (XRF), scanning electron microscopy (SEM) and metallographical analysis this thesis seeks to facilitate new interpretations on quality, production centres and usage based on analytical results. Aiming to settle some of the long lasting questions regarding the artefacts while producing results which can further the discussion by raising new questions, previously unasked.
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Brenner, Thomas Lafayette [UNESP]. "The fortaleza de minas nickel, copper and platinoids deposit: ore types, tectonics and volcanological aspects." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/103043.
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brenner_tl_dr_rcla.pdf: 5393143 bytes, checksum: 7eaa1af514649401cca544334b60985f (MD5)O depósito de Fortaleza de Minas vem sendo estudado a mais de 20 anos desde a sua descoberta em 1983 e apresenta similaridades com outros depósitos komatiíticos arqueanos descritos na literatura. Sua configuração atual reflete ação de processos metamórficos e deformacionais diversos gerando novos tipos de minério sem, no entanto, perder sua identidade primária komatiítica e permitindo reconstruir sua faciologia vulcanológica. Contexto regional A região de Fortaleza de Minas corresponde a um bloco cratônico arqueano retrabalhado na Faixa Móvel Brasília de idade neoproterozóica. Os terrenos granito-greenstone afloram em meio à metasedimentos supracrustais proterozóicos dos grupos Araxá e Canastra que compõe a nappe de Passos. O bloco arqueano corresponde ao limite sul do antigo Craton do Paramirim fazendo contato com o cinturão granulítico de Alfenas a Sul. Estudos geológicos e geofísicos recentes demonstram que esta área corresponde a uma zona de junção entre dois blocos crustais, denominados Brasília e São Paulo, que representam duas paleo-placas separadas pela zona de sutura de Alterosa. No bloco Brasília ocorrem os greenstone belts de Morro do Ferro e Pihum-i. As idades obtidas para estes greenstone belts estão distribuídas entre 2,8 e 2,9 Ga e 2,9 e 3,1 Ga respectivamente e são discutidas no capítulo 3. O greenstone belt do Morro do Ferro ocorre como faixas descontínuas e estreitas estruturadas em quilhas sinclinais representando as raízes desta seqüência greenstone. Estão fortemente deformadas e cortadas pelo sistema sinistral de falhas transcorrentes Campo do Meio responsável pela estruturação sigmoidal da região (capítulo 2) (Fig. 1, pg. 33 e Fig. 1, pg.4). O Greenstone Belt Morro do Ferro é representado por derrames komatiíticos e mais restritamente toleíticos com intercalações subordinadas de sedimentos químicos exalativos...
After 20 years of exploration and mining in the Fortaleza de Minas nickel deposit (formerly known as O`Toole) a better understanding of the geological framework and the volcanic environment was achieved. The different ore types observed in the deposit and its distribution revealed the original volcanic setting for the ore formation and also the geological evolution and transformation of the different ore types. The nickel mineralization is classified as a Type 1 deposit (Lesher and Keays, 2002). It is associated to an open trough structure of lava pathway. Later metamorphism and deformation obliterated most of the original volcanic textures and promoted a strong stretching of the ore zone and remobilization of the massive breccia ore along a major shear zone installed at the base of an upper fractionated host flow unit in contact with a footwall BIF. In the Neoproterozoic Brasiliano Cycle (0.6 Ga) a new ore type was formed of hydrothermal origin with extremely high nickel grades and PGE nuggests...(Complete abstract, click electronic address below)
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Sandré, Anne-Laure. "Nouveau procédé de dissolution-précipitation pour l’exploitation de minerais nickélifères oxydés par voie hydrométallurgique : études cinétiques, modélisation et calcul de réacteurs." Thesis, Paris, ENMP, 2012. http://www.theses.fr/2012ENMP0037.
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L'objectif de cette thèse est de bâtir un modèle prédictif d'une unité industrielle continue de dissolution de minerai de nickel/ et précipitation de fer simultanées. La méthodologie adoptée consiste dans un premier temps à réaliser des expériences en réacteur fermé ou semi-fermé pour identifier et modéliser séparément les différents phénomènes en jeu, puis dans un second temps à construire un modèle d'unité continu les rassemblant tous. Ce travail a permis certaines avancées tant sur le système retenu que sur les méthodes et modèles adoptés. Tout d'abord la thermodynamique des solutions Na-Fe(III)-H2SO4 aux alentours de 100°C a été clarifiée et la constante de solubilité de la natrojarosite Na0,84H0,16Fe2,90(SO4)2(OH)5,7 a été déduite. Ensuite les paramètres influant sur les précipitations des jarosite de sodium et potassium ont été mis en évidence et leur cinétiques de croissance ont pu être déterminées grâce à l'utilisation originale de la méthode des caractéristiques. Puis les cinétiques de dissolution des minerais ont été obtenues, en prenant en compte différentes phases du minerai et leurs granulométries. Après avoir déduit tous les paramètres nécessaires, un modèle original, permettant de simuler une cascade de réacteur de dissolution/précipitation avec recyclage a été construit puis validé. Cet outil de conception, couplé à une étude technico-économique peut permettre d'optimiser le procédéThe goal of this thesis is to build a predictive model for a continuous industrial unit combining simultaneously nickel ore dissolution and iron precipitation. A two steps method was used. First experiments in batch or semi-batch reactors were done in order to understand and model separately the different phenomenon that take place. Then all the equations and associated constants were used to build a model. This work allowed some advances both on the system studied and on the methods used. First thermodynamics of Na-Fe(III)-H2SO4 solutions in the 70-100°C temperature range was clarified and natrojarosite solubility constant Na0,84H0,16Fe2,90(SO4)2(OH)5,7 was deduced. Secondly parameters acting on sodium and potassium jarosite precipitation were highlighted and their growth kinetics were deduced through an original use of caracterisctics method. Then ore dissolution kinetics were found, taking into account different ores phases and their granulometry. After deducing all the necessary parameters, an original model allowing to simulate a cascade of dissolution/precipitation reactors with recyling loop was build and validated. This conception tool, coupled with a technico-economic study allows the optimisation of such a process
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Gencturk, Bilgehan. "Nickel Resource Estimation And Reconciliation At Turkmencardagi Laterite Deposits." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614978/index.pdf.
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In recent years nickel is mostly produced from lateritic ore deposits such as nontronite, limonite, etc. Resource estimation is difficult for laterite deposits as they have a weak and heterogeneous form. 3D modeling software are rather suitable for deposits having tabular or vein type ores. In this study the most appropriate estimation technique for resource estimation of nickel laterite deposits was investigated.
One of the known nickel laterite deposits in Turkey is located at Türkmenç
ardagi - Gö
rdes region. Since the nickel (Ni) grade recovered from drilling studies seem to be very low, a reconciliation pit having dimensions of 40 m x 40 m x 15 m in x-y-z directions was planned by Meta Nikel Kobalt Mining Company (META), the license owner of the mine, to produce nickel ore. 13 core drilling and 13 reverse circulation drilling (RC) and 26 column samplings adjacent to each drillholes were located in this area. Those three sampling results were compared to each other and as well as the actual production values obtained from reconciliation pit. On the other side 3D computer modeling was also used to model the nickel resource in Tü
rkmenç
ardagi - Gö
rdes laterites. The results obtained from both inverse distance weighting and kriging methods were compared to the results of actual production to find out the applicability of 3D modeling to laterite deposits. Modeling results showed that Ni grade of the reconciliation pit in Tü
rkmenç
ardagi - Gö
rdes, considering 0.5% Ni cut-off value, by using drillholes data, inverse distance weighting method estimates 622 tonnes with 0.553% Ni and kriging method estimates 749 tonnes with 0.527% Ni. The actual production pit results provided 4,882 tonnes of nickel ore with 0.649% Ni grade. These results show that grade values seem to be acceptable but in terms of tonnage, there are significant differences between theoretical estimated values and production values.
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Becker, Megan. "The mineralogy and crystallography of pyrrhotite from selected nickel and PGE ore deposits and its effect on flotation performance." Thesis, Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-09272009-100136/.
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Myagkiy, Andrey. "Mineralization of Nickel in saprolitic ore of New Caledonia : Dynamics of metal transfer and modeling of coupled geochemical and hydrodynamic processes." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0277/document.
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La Nouvelle-Calédonie détient d’importantes réserves de nickel latéritique et est devenue, en 2017, le cinquième producteur mondial de Ni. Ces dépôts sont habituellement considérés comme résultant d’altération latéritique intense de la péridotite, qui constitue la principale source de nickel. Ainsi, le principal modèle conceptuel de la formation des minerais de nickel latéritique en Nouvelle-Calédonie est un modèle per descensum où la plupart des éléments (Mg, Ni et Si) ont été lessivés depuis la surface, en particulier lors du développement du sol latéritique. Le nickel est ensuite reprécipité, soit dans la goethite de la latérite fine, soit au niveau de la saprolite, sous forme de goethite et de silicates Mg-Ni, dont des talc-like ou kérolite. Les observations minéralogiques et structurales récentes ainsi que les données minières ont cependant mis en évidence de nombreux types d’hétérogénéités dans les concentrations, et la distribution des porteurs de Ni. Comprendre les facteurs la mobilité de cet élément, ses mécanismes de piégeage ainsi que les paramètres chimiques et hydrodynamiques à l’origine de ce piégeage, est essentiel afin de prévoir la distribution du nickel dans les profils latéritiques en Nouvelle-Calédonie, et constitue l’objectif de cette thèse. Ce travail est basé sur le développement (i) d’un modèle 1D s’intéressant en particulier au comportement géochimique du nickel lors de l’altération de l’ophiolite, sa comparaison avec les observations in situ et une compréhension détaillée de la mobilité des éléments traces pendant le processus, et (ii) d’un modèle 2D hydro-géochimique couplé avec l’hydrodynamique complexe des profils latéritiques, améliorant ainsi la connaissance du contrôle structural sur la redistribution et la minéralisation du nickel. Tandis que les simulations 1D permettent de mieux comprendre les aspects chimiques contrôlant les processus de rétention du nickel au sein d’un profil, le modèle 2D se révèle être un outil puissant pour la compréhension de la formation des dépôts locaux les plus riches en nickel. Les résultats du modèle 2D montrent une remobilisation du nickel depuis les horizons supérieurs puis sa reprécipitation sous forme de silicates dans la saprolite. Le nickel remobilisé provient principalement de la zone saprolitique à cause de la dissolution des silicates de nickel formés précédemment ainsi que de l’olivine résiduelle de cette zone. Ce modèle a également révélé que l’horizon latéritique (et en particulier les oxy- hydroxydes de nickel) avait un faible impact dans la remobilisation du nickel. L’infiltration latérale de l’eau contenant le nickel dissout issu des formations surincombantes est à l’origine de la formation des zones les plus riches dans les parties inférieures du profil. Cette redistribution est entièrement contrôlée par l’hydrodynamique locale, la topographie ainsi que l’orientation et la position des fractures. Les modèles présentés permettent d’expliquer les processus de formation des minerais de nickel latéritique saprolitique, améliorant ainsi la compréhension des paramètres contrôlant la mobilité des éléments traces dans un environnement ultramafique. Ceci donne une nouvelle clé de distribution du nickel dans les profils actuels, qui peut devenir un outil pour la prospection minière, et la recherche de nouvelles ressources exploitablesNew Caledonia hosts significant lateritic nickel reserves, and presently became the fifth largest Ni producer in the world. These deposits are generally thought to be closely as- sociated with the intense chemical and mechanical weathering of peridotite bedrock that is a principal source of nickel. Thus, the main ore genesis model for Ni ores in New Caledonia is based on a single per descensum model where most elements (Mg, Ni, and Si) are leached from the surface, particularly, during lateritic soil development. Nickel is then concentrated either in the fine-grained laterite where goethite is the main Ni bearer, the so-called ’lateritic ore’, or below the laterites, in the saprolite level, where nickel occurs as goethite and several types of Mg-Ni silicates, in particular kerolite. Recent mineralogical and structural observations together with mining data have revealed a lot of different types of heterogeneities associated with the distribution and mineralogy of Ni bearing minerals. Therefore, in depth investigations of Ni mobility, its retardation processes along with its governing chemical and hydrodynamic parameters are of big importance for understanding and subsequent prediction of Ni distribution in profiles of New Caledonia. Such an investigation is an objective of the present work. The concept is based on the development of i) a powerful 1D model with particular emphasis on Ni geochemical behavior during ophiolite weathering, its comparison with in situ observations, and detailed understanding of trace elements mobility, and ii) 2D hydro-geochemical model coupled with complex hydrodynamics, that would additionally provide new insight into the structural control on Ni redistribution and mineralization. While the 1D simulations provide a remarkable result for understanding the chemical features that drive Ni retention processes in a profile, 2D model appears to be a powerful tool for understanding how local Ni-enrichments may form. The results of this model show the reactivation of Ni from upper horizons and its concentration in neo-formed silicates in bottom of the saprolite. The reactivated Ni comes mostly from the saprolite horizon due to the redissolution of previously formed Ni-bearing silicates and still persisting in this olivine zone. Modeling has revealed minor contribution of the laterite horizon (Ni-oxi-hydroxides) into the Ni remobilization. The lateral infiltration of water with remobilized Ni from areas such as topographic highs to downstream slope areas leads to the formation of richest deposits in this lower part of profile. The manner of redistribution is fully governed by the topographic slopes, orientation and position of the fractures. Presented models appear to be of importance in attempt of explanation of Ni mineralization processes, revealing the main keys to understanding the control of trace elements mobility in ultramafic environment. The latter gives new insights into the Ni distribution in present day profiles and, therefore, may greatly help in mineral prospecting and forecasting the distribution of future resources
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Perez, Isadora Dias. "Recuperação de cobre de uma solução sintática baseada no licor de lixiviação atmosférica do minério limonítico de níquel por troca iônica utilizando a resina quelante Dowex." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-04052018-142357/.
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Em virtude das várias aplicações do cobre, acredita-se que a demanda por esse metal irá aumentar nos próximos anos, e consequentemente, o seu preço. Dessa forma, as mineradoras enfrentam o desafio de aprimorar e aperfeiçoar os processos produtivos a fim de atender sua futura demanda. Frações de cobre podem ser encontradas no licor de lixiviação do minério limonítico de níquel e a troca iônica com adsorvente sólido é uma das tecnologias disponíveis para promover a sua recuperação e o seu reaproveitamento. O presente trabalho teve como objetivo estudar o processo de adsorção dos íons de cobre presente em um licor sintético baseado no licor de lixiviação atmosférica do minério limonítico de níquel através de um sistema de resina de troca iônica utilizando a resina quelante Dowex XUS43605. A viabilidade da técnica escolhida foi analisada em função da influência de parâmetros por meio de ensaios em batelada e coluna de leito fixo utilizando uma solução sintética. O tempo de contato, o pH, a massa de resina e a temperatura foram avaliados. A resina quelante Dowex XUS43605 mostrou-se mais seletiva para o cobre em pH igual a 1,5, tendo sido definido esse pH como o de trabalho. Verificou-se que 1g é uma dosagem suficiente para recuperar o cobre da solução em escala laboratorial considerando 50mL de solução sintética. O incremento na temperatura não alterou a adsorção do cobre pela resina, sendo determinado que a temperatura de trabalho esteja entre 25-35°C. O modelo de isotermas de adsorção de Langmuir apresentou melhor ajuste entre a resina e o cobre do que os modelos de Freundlich e de Temkin. O modelo cinético pseudosegunda-ordem descreveu o processo de adsorção considerando a quimiossorção como a etapa limitante. Os ensaios em coluna de leito fixo possibilitaram a produção de uma solução com concentração reduzida de Cu2+ em 93% na etapa de carregamento. Pela etapa de eluição com ácido sulfúrico (H2SO4) 1mol/L, obteve-se uma solução 10 vezes mais concentrada em Cu2+ com relação à solução sintética. A solução resultante da etapa de eluição seguiu para os ensaios de precipitação, a qual permitiu a separação do cobre dos íons metálicos pela ação do agente precipitante CaCO3 e a geração de um precipitado composto por três fases: brochantite [Cu4SO4(OH)6], posnjatike [Cu4SO4(OH)6.H2O] e gesso (CaSO4.2H2O).Considering the various applications of copper, it is believed that the demand for copper will increase in the coming years and, consequently, its price. Hence, the mining companies face the challenge of improving the productive processes to supply their future demand. Copper fractions can be found in liquor leaching nickel limonite ore and ion exchange with solid adsorbent is one of the available technologies which promote its recovery and reuse. The present work was aimed at studying the adsorption process of copper ions present in a synthetic liquor based on the atmospheric leaching liquor of the nickel limonite ore through an ion exchange resin system using Dowex XUS43605 chelating resin. The feasibility of the chosen technique was analyzed in relation to the influence of parameters by means of batch and fixed bed tests using a synthetic solution. The contact time, pH, amount of resin and temperature were evaluated. Dowex XUS43605 chelating resin showed to be more selective for copper at pH 1.5, and this pH was defined as the working pH. It has been found that 1g is a sufficient dosage to recover copper from the solution on a laboratory scale considering 50mL of synthetic solution. The increase in temperature did not change the adsorption of the copper by the resin, and it was determined that the working temperature is between 25-35°C. The Langmuir adsorption isotherms model showed a better fit between resin and copper than the Freundlich and Temkin models. The pseudosecond-order describes the sorption process and it indicates that the rate-limiting step is chemisorption. The fixed bed column tests allowed the production of a solution with reduced concentration of Cu2+ in 93% the loading step. By the elution step with 1mol/L of sulfuric acid (H2SO4), a solution 10 times more concentrated in Cu2+ was obtained in relation to the synthetic solution. The solution from the elution step followed to the precipitation tests, which allowed the separation of copper from the metal ions by the action of the precipitating agent CaCO3 and the generation of a precipitate composed of three phases: brochantite [Cu4SO4(OH)6], posnjatike [CuSO4(OH)6.H2O] and gypsum (CaSO4.2H2O).
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Jardine, Mitchel. "Three dimensional quantitative textural analysis of nickel sulphide ore using X-ray computed tomography and grey level co-occurrence matrices on drill core." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20489.
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Alongside the global trend to mine and process lower grade and more mineralogically complex ores, there has been an increased awareness of the prevalence of ore heterogeneity. Ore texture - the interrelationship of minerals comprising a rock, has been identified as one of the primary geometallurgical indicators of ore variability. It is well known that a relationship exists between ore texture and the resultant metallurgical performance (ore hardness, throughput, liberation, grade, recovery). Consequently, there exists a need to rapidly, routinely, cost effectively, and reliably quantify ore texture and its variability prior to mining. This information can thereafter be incorporated into the geometallurgical block model and used for decision making informing mine planning, plant operation and optimisation, forecasting, and mine closure. The ability to rapidly, routinely, cost effectively and reliably quantify ore texture remains an ongoing challenge. In this study, the use of 3D X-ray computed tomography (XCT) is proposed as an innovative solution to non-destructively image the internal structure of drill core. Thereafter, an established, discipline independent two dimensional (2D) image analysis technique known as grey level co-occurrence matrices (GLCM) is specially adapted into three dimensions (3D) to quantify ore texture using XCT grey level volumes of drill core.
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Michaud, Michael Julien. "The geology, petrology, geochemistry and platinum-group element-gold-copper-nickel ore assemblage of the Roby Zone, Lac des Iles mafic-ultramafic Complex, northwestern Ontario." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0027/MQ52068.pdf.
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Brenner, Thomas Lafayette. "The fortaleza de minas nickel, copper and platinoids deposit : ore types, tectonics and volcanological aspects = A jazida de níquel, cobre e platinóides de fortaleza de minas : aspectos tectônicos, vulcanológicos e tipos de minérios /." Rio Claro : [s.n.], 2006. http://hdl.handle.net/11449/103043.
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Orientador: Sebastião Gomes de CarvalhoBanca: Aroldo Misi
Banca: Yociteru Hasui
Banca: Jorge Silva Bettencourt
Banca: Antenor Zanardo
O presente trabalho reúne 3 artigos científicos, já formalizados para publicação em revistas internacionais, foi confeccionado para ser apresentado como tese de doutorado
Artigos em inglês, introdução e resumo em português
Resumo: O depósito de Fortaleza de Minas vem sendo estudado a mais de 20 anos desde a sua descoberta em 1983 e apresenta similaridades com outros depósitos komatiíticos arqueanos descritos na literatura. Sua configuração atual reflete ação de processos metamórficos e deformacionais diversos gerando novos tipos de minério sem, no entanto, perder sua identidade primária komatiítica e permitindo reconstruir sua faciologia vulcanológica. Contexto regional A região de Fortaleza de Minas corresponde a um bloco cratônico arqueano retrabalhado na Faixa Móvel Brasília de idade neoproterozóica. Os terrenos granito-greenstone afloram em meio à metasedimentos supracrustais proterozóicos dos grupos Araxá e Canastra que compõe a nappe de Passos. O bloco arqueano corresponde ao limite sul do antigo Craton do Paramirim fazendo contato com o cinturão granulítico de Alfenas a Sul. Estudos geológicos e geofísicos recentes demonstram que esta área corresponde a uma zona de junção entre dois blocos crustais, denominados Brasília e São Paulo, que representam duas paleo-placas separadas pela zona de sutura de Alterosa. No bloco Brasília ocorrem os greenstone belts de Morro do Ferro e Pihum-i. As idades obtidas para estes greenstone belts estão distribuídas entre 2,8 e 2,9 Ga e 2,9 e 3,1 Ga respectivamente e são discutidas no capítulo 3. O greenstone belt do Morro do Ferro ocorre como faixas descontínuas e estreitas estruturadas em quilhas sinclinais representando as raízes desta seqüência greenstone. Estão fortemente deformadas e cortadas pelo sistema sinistral de falhas transcorrentes Campo do Meio responsável pela estruturação sigmoidal da região (capítulo 2) (Fig. 1, pg. 33 e Fig. 1, pg.4). O Greenstone Belt Morro do Ferro é representado por derrames komatiíticos e mais restritamente toleíticos com intercalações subordinadas de sedimentos químicos exalativos...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: After 20 years of exploration and mining in the Fortaleza de Minas nickel deposit (formerly known as O'Toole) a better understanding of the geological framework and the volcanic environment was achieved. The different ore types observed in the deposit and its distribution revealed the original volcanic setting for the ore formation and also the geological evolution and transformation of the different ore types. The nickel mineralization is classified as a Type 1 deposit (Lesher and Keays, 2002). It is associated to an open trough structure of lava pathway. Later metamorphism and deformation obliterated most of the original volcanic textures and promoted a strong stretching of the ore zone and remobilization of the massive breccia ore along a major shear zone installed at the base of an upper fractionated host flow unit in contact with a footwall BIF. In the Neoproterozoic Brasiliano Cycle (0.6 Ga) a new ore type was formed of hydrothermal origin with extremely high nickel grades and PGE nuggests...(Complete abstract, click electronic address below)
Doutor
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Aliprandini, Paula. "O uso da extração por solventes para tratamento de licor de lixiviação de minério limonítico de níquel." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-23022017-110109/.
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O minério limonítico de níquel é considerado uma fonte de níquel e cobalto a partir de mineração. No entanto, o minério é heterogêneo e a concentração dos metais varia conforme a localização. Sendo assim, é necessário o desenvolvimento de uma metodologia que permita determinar os parâmetros de operação de um processo de separação de metais levando em consideração a composição de cada minério. No processo hidrometalúrgico, diversas técnicas de purificação ou separação dos metais podem ser usadas. O presente trabalho estudou o uso da extração por solventes para tratar o licor baseado no lixiviado de minério limonítico de níquel. No processo de extração por solventes foram determinados os parâmetros de extração dos metais como: pH, concentração do extratante na fase orgânica e diluído em querosene, relação entre as fases aquosa e orgânica (A/O) e número de contatos contracorrente teóricos para extração do metal. A extração de 100% do ferro utilizando Cyanex 272 foi determinada em pH 2, concentração do extratante 25% em volume diluído em querosene, relação A/O 1/3 e três contatos contracorrente. Durante a extração do ferro também houve coextração de 27% do cobalto. Foi possível recuperar o cobre da solução através da extração utilizando Acorga M5640 em pH 2, concentração do extratante na fase orgânica igual 5% v/v, relação entre as fases 1/1 e um contato contracorrente. O alumínio e o zinco foram extraídos em pH 3,5, utilizado Cyanex 272 como extratante na concentração 25% em volume, relação A/O 1/2 e dois contatos contracorrente. A fim de obter uma solução aquosa contendo apenas níquel em solução, a última etapa foi a remoção dos metais remanescentes na solução (cobalto, cromo, magnésio e manganês) utilizando Cyanex 272. O pH para essa extração foi 5, a concentração do extratante 20% v/v, relação entre as fases 1/1 e cinco contatos contracorrente. Ao final, foi possível obter uma solução aquosa contendo níquel em solução na concentração 2,52g/L, o que corresponde a 100% do níquel presente na solução sintética. Além do níquel, 0,19 g/L de magnésio e 0,008g/L de cromo permaneceram na solução final.Nickel limonite ore is a source of nickel and cobalt. However, the ore is heterogeneous and concentration changes according the location of the ore. Therefore, determination of the operating parameters is required to separate the metals taking into account the composition of these ores. Hydrometallurgical process is used to treat leach liquor from ores. This work studied the treatment of synthetic solution based on leach liquor of nickel limonite ore by solvent extraction. During the study was determinated the metals extraction parameters as pH, extractant concentration in the organic phase, aqueous and organic ratio (A/O) and number of theoretical extraction stages. The extraction of iron was 100% using Cyanex 272 at pH 2, extractant concentration 25% (v/v) and three extraction stages at an A/O ratio 1/3. Nevertheless, during the extraction of iron, cobalt was co-extracted. The cobalt lost was 27% at the parameters used to extract. It was possible to recover copper from the synthetic solution using Acorga M5640 as extractant at pH 2, extractant concentration 5% v/v, one extraction stage and an A/O ratio 1/1. Aluminium and zinc were removed from synthetic solution at pH 3.5, organic phase with 25% v/v of Cyanex 272 and two extraction stages at an A/O ratio 1/2. The last part of work was removed cobalt, chromium, magnesium and manganese from the aqueous solution. The reason is staying just nickel in the final solution. Cyanex 272 at pH 5 and 20% v/v concentration was used and five extraction stages and an A/O ratio 1/1 was necessary to extract the metals. The finally solution was composed by 2.52g/L of nickel, corresponding 100% of nickel from synthetic leach liquor of nickel limonite ore. In addition, 0.19g/L of magnesium and 0.008g/L of chromium staying at solution.
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Contessotto, Renato. "Classificação de domínios mineralógicos e caracterização de minérios de níquel da mina de Santa Rita - BA, em apoio à geometalurgia." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-22062017-141549/.
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A Mina de Santa Rita, situada no complexo máfico-ultramáfico Fazenda Mirabela, é uma intrusão máfica-ultramáfica, mineralizada a sulfetos de níquel e cobre, situada no sudeste do Estado da Bahia, município de Itagibá. Esse depósito é composto por rochas de idade Paleoproterozóica, metamorfizadas em fácies granulito. Os sulfetos de níquel e cobre ocorrem disseminados e, preferencialmente, associados a harzburgitos, olivina ortopiroxenitos e ortopiroxenitos. O minério é composto por uma grande variedade de Mg-silicatos, sendo que o níquel ocorre essencialmente como pentlandita nos peridotitos, além de se apresentar como elemento menor em silicatos e espinélios em rochas mais máficas. Informações de processo demonstram a impossibilidade de se estabelecer uma correlação robusta entre a composição química do minério e seu comportamento na etapa de beneficiamento mineral. Desta forma, o conhecimento da variabilidade mineralógica no depósito é de fundamental importância para o planejamento de lavra e processamento mineral. Mais de 300 amostras do plano de mineração de curto prazo (2013-2017) relativas a intervalos de furos de sondagem considerados no estudo de viabilidade econômica (período de 1985-2004) foram agrupadas em domínios mineralógicos, utilizando a análise estatística multivariada de dados de difração de raios X (DRX-AEM). Dezessete domínios mineralógicos inicialmente definidos são essencialmente diferenciados com base na presença e conteúdos relativos dos principais minerais de ganga: serpentina, olivina e piroxênio. Amostras representativas dos principais domínios mineralógicos, pré-definidos por DRX-AEM, foram submetidas a estudos de caracterização mineralógica de detalhe por análise de imagens (MEV-MLA). Os resultados indicam que os grupos com composições mais peridotíticas e/ou carbonáticas, com maiores conteúdos de serpentina, apresentam menor tempo de moagem para atingir P95 igual a 0,15 mm; maior alteração dos grãos de pentlandita; maior parcela de total de níquel associado a silicatos; menor grau de liberação dos sulfetos; e maior quantidade de sulfetos abaixo de 10 ?m, em relação aos grupos de composição mais piroxenítica.The Santa Rita mine, located in the mafic-ultramafic complex Fazenda Mirabela, is a mafic-ultramafic intrusion mineralized to nickel and copper sulphides located in the southeast of Bahia state, Itagibá municipality. The nickel sulphide deposit comprises a portion of a mafic-ultramafic layered complex under granulite metamorphism facies. Disseminated Ni and Cu sulphides form a stratiform body parallel to the lithostratigraphic contacts extending upwards essentially from the harzburgite unit and through the olivine orthopyroxenite unit. The nickel content is mainly associated to pentlandite in peridotitic rocks but also enriched in silicates and spinels in mafic rocks (dunites). Industrial plant benchmark data have shown the unfeasibility of establishing a strong relation between the ore chemical composition and its behavior in the mineral beneficiation process. Therefore, the knowledge of the mineralogical variability in the deposit is crucial for mine planning and mineral/metallurgical processing. More than 300 samples from drill core samples from the feasibility studies (period of 1985-2004) included in the short-term mining plan (2013-2017) were clustered into geological domains applying multivariate statistical analysis (MSA) of X-ray diffraction data (XRD). Results discriminated seventeen initial mineralogical domains considering the content of major gangue minerals: serpentine, olivine and pyroxene. Representative samples of the main mineralogical domains pre-defined by XRD-MSA ore-types were later subject to sieve size analysis followed by detailed mineralogical studies by automated SEM image analysis (MLA). The results indicate that groups with more peridotite and / or carbonatic compositions, with higher content of serpentine, have less time of grinding to reach P95 equal to 0,15 mm; high level of pentlandite alteration; greater portion of nickel associated into silicates; lower sulphides liberation degree; and a higher amount of sulphides below 10 ?m; in relation to the most pyroxenic composition groups.
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Pappas, Adlreburg Nickolas. "To Make Iron of Iron : A Comprehensive Analytical Study of Spade Shaped Iron Bars." Thesis, Stockholms universitet, Arkeologiska forskningslaboratoriet, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-145694.
Full textAbstract:
This thesis aims to provide adequate analytical information on the spade shaped iron bars of Norrland and central Sweden. While their significance has been thoroughly debated for decades, analytical research on them has been confined to cases of single artefacts or theoretical interpretations of their value, meaning and origin. In this study a comprehensive approach is taken into consideration. Based on X-Ray fluorescence (XRF), scanning electron microscopy (SEM) and metallographical analysis this thesis seeks to facilitate new interpretations on quality, production centres and usage based on analytical results. Aiming to settle some of the long lasting questions regarding the artefacts while producing results which can further the discussion by raising new questions, previously unasked.
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Kahn, Riyard. "Optimisation of reagent addition during flotation of a nickel sulphide ore at the Nkomati Mine concentrator." Thesis, 2017. http://hdl.handle.net/10539/22965.
Full textAbstract:
A dissertation submitted to the faculty of Engineering and the Built Environment, University of Witwatersrand in fulfilment of the requirements for the degree of Master of Science in Engineering
28 January 2017Batch scale laboratory testwork was conducted to evaluate collector and depressant addition on flotation performance of a nickel sulphide ore. The objectives of the study were to: 1. develop an understanding of the effects of collector and depressant dosage, and its interactive effects, on flotation performance and 2. determine the effect of stage dosing collector and depressant on flotation performance. Testwork was conducted on the Nkomati Main Mineralized zone orebody, a nickel sulphide orebody in the Mpumulanga Province of South Africa consisting of pentlandite, chalcopyrite, pyrrhotite, pyrite and magnesium bearing silicates. Characterisation testwork was conducted, including mineralogy on the major plant streams (by QEMSCAN) and a process survey. The results indicated that there was potential to increase the recovery of coarse pentlandite and that major nickel losses were observed in ultrafine pentlandite. Milling optimisation requires the minimisation of ultrafine generation while ensuring adequate liberation of the course nickel. Stage dosing of collector at nodal points (where more than one stream meets) is currently practiced on the plant, however, its effect had not yet been quantified on the plant or in the laboratory. Stage dosing of depressant is currently practiced on the cleaner flotation stage, however, this too has not been compared to upfront dosage on its own. Significant gangue depression was noted specifically for the cell at which stage dosing was done. The current study would provide an understanding of the current practices with the possibility of offering improvements. The addition of collector progressively improved the hydrophobicity of the sulphide minerals and gangue (with particular emphasis on magnesium bearing gangue), improving recovery significantly. As a result of additional gangue recovery at the higher collector dosages, increased depressant dosages were required to maximise nickel recovery. The collector improved valuable mineral recovery, however, gangue recovery was increased simultaneously, albeit at a reduced rate or in reduced quantities. Furthermore, increased gangue entrainment was evident at higher collector dosages from the increase in water recovery. Excessive depressant addition destabilised the froth phase by the rejection of froth stabilising gangue, which resulted in reduced recovery of the valuable minerals. Therefore, a careful balance must be maintained in order to maximise nickel recovery. Iron recovery was markedly increased at higher reagent dosages, indicative of increased pyrrhotite recovery. Pyrrhotite, although containing nickel, reduces the concentrate grade and may need to be depressed in the latter stages of flotation to ensure the final concentrate specification is achieved. This is an important observation as any improvement in nickel recovery in the roughing stages must be evaluated against the subsequent effect on the cleaning stages. Stage dosing both collector and depressant, individually and collectively, proved to be beneficial by improving the nickel recovery. Stage dosing of both collector and depressant produced higher recoveries than stage dosing of the reagents individually. The time at which the reagent is dosed also proved to have an effect on the performance with an increased dosage in the latter stages providing the highest recovery. The typical recovery by size performance for flotation is characterised by low recovery of fines and coarse with an optimum recovery of an intermediate size fraction. Stage dosing ensures that fine particles are recovered with minimal reagent addition upfront, thereby, coarser particles can be effectively recovered once the high reagent consuming fines are removed. The results have indicated that stage dosing improved the recovery of both coarse and fine particles, whilst reducing the recovery of the intermediate size fraction. Stage dosing can be implemented for two reasons: 1. maximising recovery 2. minimising reagent consumption to achieve the same recovery as upfront dosing A financial evaluation should be conducted to quantify the optimum operating solution. Minimising reagent consumption could be beneficial under conditions of very low commodity prices and excessive reagent costs.
MT2017
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Clissold, Meagan E., University of Western Sydney, College of Health and Science, and School of Natural Sciences. "Aspects of the supergene geochemistry of copper, nickel and bismuth." 2007. http://handle.uws.edu.au:8081/1959.7/11433.
Full textAbstract:
The solution geochemical conditions associated with the development of supergene copper mineralisation in the E22, E26 and E27 deposits at Northparkes, New South Wales, have been explored. Determination of a stability constant for sampleite [NaCaCu5(PO4)4Cl·5H2O], a conspicuous species in the upper oxidised zone of E26, has led to an understanding of the differences between the three deposits in terms of the influence of groundwater geochemistry on their mineralogical diversity. Modelling of copper dispersion from the three deposits using current ground water compositions as proxies for past solution conditions has shown that the elevated chloride concentrations associated with E26 have negligible influence on total dissolved copper concentrations over a wide pH range. The results are discussed with respect to applications in exploration geochemistry for the discovery of new ore deposits in the region. Determination of a stability constant for lavendulan [NaCaCu5(AsO4)4Cl·5H2O], the arsenate isomorph of sampleite, suggests that solid solution between lavendulan and sampleite is likely to be extensive and this has been established by reference to mineral compositions from a number of deposits. Activity-activity phase diagrams have been developed to explain the common mineral associates of lavendulan and differences between the analogous phosphate and arsenate systems. With respect to the occurrence of lavendulan in the oxidised zone of the Widgiemooltha 132 N ore body, Western Australia, its crystal chemistry explains why Ni does not substitute for Cu in the lattice. This is despite Ni being abundantly available in the deposit and substituting freely into other copper-based minerals. The substitution of Ni for Cu was explored in a study of supposedly Ni-rich paratacamite, Cu2Cl(OH)3, from the deposit. It transpires that much of this is a new mineral, gillardite, Cu3NiCl(OH)6, the isomorph of herbertsmithite, Cu3ZnCl(OH)6. The nature of gillardite was thoroughly investigated and the mineral was approved as a new species by the International Mineralogical Association. A high resolution single-crystal X-ray structure of gillardite has been completed. In addition, the substitution of Ni in simple carbonate lattices has been explored as gaspéite, NiCO3, Ni-rich magnesite, MgCO3, and calcite, CaCO3, are all common species in the oxidised zone of the Widgiemooltha 132 N deposit. Attention was subsequently focussed on the geochemistry of the element Bi, with special reference to deposits of the Kingsgate region, New South Wales. This study has led to a modern assessment of the Mo-Bi deposits in the area and new Bi sulfosalts from the Wolfram pipe at Kingsgate are described. A survey of secondary Bi minerals from a host of deposits has led to the development of a model for the dispersion of Bi in the supergene environment, which will have widespread applications in exploration geochemistry where Bi is used as a pathfinder element. Calculations of aqueous Bi species in equilibrium with bismite, Bi2O3, bismoclite, BiOCl, and bismutite, Bi2O2CO3, over a wide pH range show that the element is very insoluble under ambient oxidising conditions. It is noted that the results of previous geochemical exploration campaigns in the region will have to be reassessed.Doctor of Philosophy (PhD)
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Clissold, Meagan E. "Aspects of the supergene geochemistry of copper, nickel and bismuth." Thesis, 2007. http://handle.uws.edu.au:8081/1959.7/11433.
Full textAbstract:
The solution geochemical conditions associated with the development of supergene copper mineralisation in the E22, E26 and E27 deposits at Northparkes, New South Wales, have been explored. Determination of a stability constant for sampleite [NaCaCu5(PO4)4Cl·5H2O], a conspicuous species in the upper oxidised zone of E26, has led to an understanding of the differences between the three deposits in terms of the influence of groundwater geochemistry on their mineralogical diversity. Modelling of copper dispersion from the three deposits using current ground water compositions as proxies for past solution conditions has shown that the elevated chloride concentrations associated with E26 have negligible influence on total dissolved copper concentrations over a wide pH range. The results are discussed with respect to applications in exploration geochemistry for the discovery of new ore deposits in the region. Determination of a stability constant for lavendulan [NaCaCu5(AsO4)4Cl·5H2O], the arsenate isomorph of sampleite, suggests that solid solution between lavendulan and sampleite is likely to be extensive and this has been established by reference to mineral compositions from a number of deposits. Activity-activity phase diagrams have been developed to explain the common mineral associates of lavendulan and differences between the analogous phosphate and arsenate systems. With respect to the occurrence of lavendulan in the oxidised zone of the Widgiemooltha 132 N ore body, Western Australia, its crystal chemistry explains why Ni does not substitute for Cu in the lattice. This is despite Ni being abundantly available in the deposit and substituting freely into other copper-based minerals. The substitution of Ni for Cu was explored in a study of supposedly Ni-rich paratacamite, Cu2Cl(OH)3, from the deposit. It transpires that much of this is a new mineral, gillardite, Cu3NiCl(OH)6, the isomorph of herbertsmithite, Cu3ZnCl(OH)6. The nature of gillardite was thoroughly investigated and the mineral was approved as a new species by the International Mineralogical Association. A high resolution single-crystal X-ray structure of gillardite has been completed. In addition, the substitution of Ni in simple carbonate lattices has been explored as gaspéite, NiCO3, Ni-rich magnesite, MgCO3, and calcite, CaCO3, are all common species in the oxidised zone of the Widgiemooltha 132 N deposit. Attention was subsequently focussed on the geochemistry of the element Bi, with special reference to deposits of the Kingsgate region, New South Wales. This study has led to a modern assessment of the Mo-Bi deposits in the area and new Bi sulfosalts from the Wolfram pipe at Kingsgate are described. A survey of secondary Bi minerals from a host of deposits has led to the development of a model for the dispersion of Bi in the supergene environment, which will have widespread applications in exploration geochemistry where Bi is used as a pathfinder element. Calculations of aqueous Bi species in equilibrium with bismite, Bi2O3, bismoclite, BiOCl, and bismutite, Bi2O2CO3, over a wide pH range show that the element is very insoluble under ambient oxidising conditions. It is noted that the results of previous geochemical exploration campaigns in the region will have to be reassessed.
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Pietrobon, Michael C. "Chemical aspects in the flotation of pentlandite in Western Australian nickel ores." 1996. http://arrow.unisa.edu.au:8081/1959.8/84872.
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Chiwundura, Phillip. "Application of indicator kriging and conditional simulation in assessment of grade uncertainty in Hunters road magmatic sulphide nickel deposit in Zimbabwe." Thesis, 2017. https://hdl.handle.net/10539/24082.
Full textAbstract:
A research project report submitted to the Faculty of Engineering and the Built
Environment, University of the Witwatersrand, in fulfilment of the requirements
for the degree of Masters of Science in Engineering, 2017The assessment of local and spatial uncertainty associated with a regionalised variable such as nickel grade at Hunters Road magmatic sulphide deposit is one of the critical elements in the resource estimation. The study focused on the application of Multiple Indicator Kriging (MIK) and Sequential Gaussian Simulation (SGS) in the estimation of recoverable resources and the assessment of grade uncertainty at Hunters Road’s Western orebody. The Hunters Road Western orebody was divided into two domains namely the Eastern and the Western domains and was evaluated based on 172 drill holes. MIK and SGS were performed using Datamine Studio RM module. The combined Mineral Resources estimate for the Western orebody at a cut-off grade of 0.40%Ni is 32.30Mt at an average grade of 0.57%Ni, equivalent to 183kt of contained nickel metal. SGS results indicated low uncertainty associated with Hunters Road nickel project with 90% probability of an average true grade above cut-off, lying within +/-3% of the estimated block grade. The estimate of the mean based on SGS was 0.55%Ni and 0.57% Ni for the Western and Eastern domains respectively. MIK results were highly comparable with SGS E-type estimates while the most recent Ordinary Kriging (OK) based estimates by BNC dated May 2006, overstated the resources tonnage and underestimated the grade compared to the MIK estimates. It was concluded that MIK produced better estimates of recoverable resources than OK. However, since only E-type estimates were produced by MIK, post processing of “composite” conditional cumulative distribution function (ccdf) results using a relevant change of support algorithm such as affine correction is recommended. Although SGS produced a good measure of uncertainty around nickel grades, post processing of realisations using a different software such as Isatis has been recommended together with combined simulation of both grade and tonnage.
XL2018
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Chen, Zhongxing. "Development of micro-sampling techniques utilizing inductively coupled plasma-mass spectrometry (ICP-MS) and their application to geochemical studies of precious metal-rich nickel-copper ores at Sudbury /." 1993. http://collections.mun.ca/u?/theses,120173.
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