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By B. Grinbaum

The solvent extraction of Cu from acidic leach solutions is carried out using oxime extractants. The mechanism can be described as liquid ion exchange, where a labile H+ in the oxime replaces Cu++ ion from the pregnant leach solution. The process is reversible and, at high acidity, the copper is stripped back to the aqueous phase. As the extraction proceeds, the acidity of the aqueous phase increases and the equilibrium may shift against the extraction reaction. This phenomenon may become significant in leach solutions with high copper concentration, where large amounts of acid are transferred from the solvent into the aqueous phase. An efficient way to increase the recovery of copper consists of splitting the extraction into two circuits, and either neutralizing with lime or extracting the excess acid of the intermediate raffinate. In the second case, the acid can extracted using a solvent, which can be stripped with a base, e.g., NaOH or ammonia. A third option is direct neutralization with soluble basic salt, e.g., Na2CO3, within a single extraction battery. The choice of the preferred process depends on the specific process demands and on the relative availability and price of the raw materials and by-products price.

Jan 1, 2007

By J. W. Scott, G. G. R. Falkenberg

"The Syncrude project is an integrated complex designed to mine, extract and upgrade bitumen from the Athabasca tar sands to produce 129,000 barrels per day of synthetic crude oil. This paper provides a brief general description of the location, history and geology of the tar sands and the overall organization and structure of the project. The major emphasis and the bulk of the detail presented deals with the extraction plant; a material handling and mineral processing installation designed to treat 312,000 tons per day of tar sand feed.History of the Tar SandsThe Athabasca tar sand deposit was recorded in 1788 by Peter Pond, however the first serious geological mapping and exploration did not begin until 1915. Little interest was taken in the deposits until the Second World War, when the governments of Canada and Alberta conducted an extensive exploration program. In addition a number of pilot plants were sponsored during the 1940 -1950 decade. The hot water separation process was successfully demonstrated on the pilot plant scale during 1948 -49, and was established commercially in 1967 in the G.C.O.S. plant. The Syncrude plant, due to come on stream in April 1978, also employs the hot water separation process."

Jan 1, 1978

By E. Marcotte

"Technology developments and improvements are imperative to maintain a viable mineral processing industry. In order to achieve optimum implementation of technology in processing plants, safety conscious and efficient work forces are required. Effective management methods are required to prevent employee injuries, equipment or environmental damage and process losses. Good leadership also provides for employees to perform their work in the safest and most efficient manners to attain optimum recoveries of the valuable minerals and produce high quality mill products. Equipment and processes must be designed, operated and maintained as required to assure safe and efficient mineral processing.INTRODUCTIONThe Canadian mining industry must contend with many challenges to attain and maintain a competitive position in today's global market. Canadian Mineral Processors play a vital role in meeting the challenges and achieving optimum mineral productivity.Ongoing technology developments and improvements continue to be imperative to maintain a viable mineral processing industry. The efficient implementation of technology developments requires a safety conscious, skillful and productive work force.In addition to technical and human resources, challenges may also include governments, labour unions or environmental advocates who at times may appear to be misguided or unrealistic. Canadian Mineral Processors must not allow themselves to be overwhelmed by these apparent obstacles but must use their demonstrated ingenuity to achieve successful solutions.It should be recognized that the majority of the Canadian work force are, in fact, a potentially talented and skillful people with ambitions to excel. As leaders of people, we must provide the methodology, incentive and direction that will allow our work forces to realize their ambitions. If the potentials of our work forces are not recognized and leadership is not properly exercised much loss will occur. That is, safe effective and efficient work will not be achieved."

Jan 1, 1993

By T. T. Chen, J. E. Dutrizac, G. Poirier

In the Waelz kiln process, EAF dust is converted to an Fe-rich slag, a (Zn, Fe)-rich dust that is recycled to the kiln and the Zn-rich Waelz oxide which is subsequently up-graded for the recovery of zinc. To clarify the reactions occurring, the Waelz kiln products from a European Waelz plant were characterized mineralogically to determine the mineral species present, their micro-textures and the metal carriers. The EAF dust contains 27 % Zn, and consists mainly of ZnFe2O4 and ZnO, together with minor to trace amounts of NaCl, PbCl2, KCl, CaO, Ca2Fe2O5, Fe203, FRO, Pb oxide and various Ca-Fe-Al-Mn silicates. The KCI and NaCI sometimes agglomerate the other particles. The slag consists of nodules which often exhibit colloform structures. The slag contains of variable amounts of Fe, FeO(OH), FeO, gypsum, Ca(OH)2, Ca2SiO4 and various Ca-Fe¬Al-Mg-Mn silicates as well as minor to trace amounts of ZnFe2O4, Cr-Fe oxide, Mn-Fe oxide and other species. The Waelz oxide contains 57-61 % Zn, and consists predominantly of ZnO, with minor to trace amounts of KCI NaCl, Pb(OH)Cl, Pb20(SO4), Pb chloride, ZnSO4, ZnFe2O4, Ca2SiO4, Ca2Fe2O5, Ca-Fe silicate and NaZn4(SO4)(OH)6Cl.6H2O. The KCI agglomerates the other particles in the Waelz oxide. The recycled dust appears to be a mixture of EAF dust and Waelz oxide, but it contains relatively more coarser-grained metallic Pb and Pb oxide particles.

Jan 1, 2004

By M. Takebayashi, K. Takenaka, S. Matsubara, T. Yoneyama

The cathode production of Toyo Smelter and Refinery, owned by Sumitomo Metal Mining Co., Ltd. reached 450,000 tons per year in 2016 with three tank houses. Niihama tank house commenced operations in 1919 with conventional sheet cathode technology. Approximately 100 years of operation experience and the technical development enabled that the current density of Niihama tank house and the Toyo tank house #1 increased to 320 A/m2. These operation techniques were utilized at the Toyo tank house #2 which started in 2005, and its current density reached up to 350 A/m2 with permanent cathode technology. In order to achieve high current efficiency under condition of 350 A/m2 operation at Toyo tank house #2, continued efforts had been made to verticality of anodes and permanent cathodes. To improve verticality of anodes and cathodes, reduction of short circuit ratio by changing the shape of the anode, optimizing the anode pressing machine and off-line process for rectifying the distortion of permanent cathodes was carried out. In addition, concentration control of electrolyte and expansion of Ni removing ability from the electrolyte prevented passivation. Finally, more than 96% of the current efficiency was stably confirmed. INTRODUCTION Today, Toyo Smelter and Refinery of Sumitomo Metal Mining operates three tank houses in Japan, namely, Toyo tank house #1, Toyo tank house #2, and Niihama tank house with a total capacity of 450,000 metric tons of copper cathodes. Figure 1 shows the trend of cathode copper production and the current density at three tank houses over the last 10 years. Cathode production by Toyo Smelter and Refinery reached 450,000 tons per year in 2016 with three tank houses.

Jan 1, 2019

By Jean-Francois Magnan

"The old conventional process to produce lithium raw material dates from 1954 (CA patent #504477A). This process produces low purity lithium carbonate (Li2CO3) only. To obtain battery-grade carbonate, another polishing process is needed. To further obtain lithium hydroxide, another chemical conversion process is needed. That is why historically, the value of lithium hydroxide has always been higher than that of the lithium carbonate precursor. With the old conventional process, the low quality lithium carbonate is precipitated from a lithium sulfate solution (Li2SO4) by adding soda ash (sodium carbonate and its impurities). The resulting reaction produces significant quantities of sodium sulfate (salt cake) as a by-product with amounts larger than the impure Li2CO3 recovered with part of the soda impurities. When this conventional process was invented, the salt cake by-product was not an issue: it was discarded in a river near the plant. This practice cannot be done today in North America. While looking to find a solution for salt cake, electrolytic salt splitting of Na2SO4 into NaOH and dilute sulfuric acid appears as a technically feasible solution to get a rid of the salt cake. However, the sodium sulfate salt splitting process has difficulties to economically compete with the chlor-alkali process, which produces millions of tons of NaOH from sodium chloride (NaCl) every year.In contrast, the process developed by Nemaska to directly produce LiOH by Li2SO4 salt splitting not only solves the environmental problems related to the conventional process to produce lithium carbonate raw material, it also produces very high purity lithium hydroxide monohydrate directly at very competitive OPEX cost in comparison with industry peers (Figure 1). It also drastically reduces the amount of reagent and the direct greenhouse gas emissions."

Jan 1, 2016

By Jorge Blanco, Joaquin Gotor, Enrique Delgado, Carlos Frias

Since 2009 Cobre las Cruces (CLC) has successfully operated a sustainable mining business near Seville, Spain, applying the most advanced hydrometallurgical technologies to process secondary copper sulphide ores through atmospheric leaching in ferric sulphate media and using oxygen sparging in a cascade of ten reactors. In comparison to conventional copper smelters, the CLC hydrometallurgical process does not generate SO2 gas, airborne emissions or slags. The copper ore is ground and sent directly to atmospheric leaching reactors; flotation is not required, and consequently, copper extraction is maximized at 93-95%, while producing 72,000 t/y copper cathodes of the highest purity (99.999 wt.% Cu, Grade A). Reserves for the CLC deposit were estimated at 16 million tonnes of ore averaging over 6 wt.% Cu and containing principally a chalcocite mineralization. Other copper bearing species include digenite, covellite, chalcopyrite, bornite and enargite. Pyrite represents over 70 wt.% of the ore. In the CLC leaching process, chalcocite reacts with ferric sulphate at approximately 90 ºC and copper is released into solution while ferric ions are reduced to ferrous ions. The ferric sulphate leachant is regenerated continuously by oxygen injection and consumes sulphuric acid. It is remarked that pyrite plays a crucial role to yield high copper leaching rates. When pyrite is oxidized, a small proportion of iron is co-leached and some sulphuric acid is generated. The CLC leaching technology has been designed to allow a certain level of pyrite oxidation, which is positive in many ways: (i) to maintain a Fe/Cu ratio in solution; (ii) to facilitate Fe(II) oxidation; (iii) to produce a high redox potential; and (iv) to counterbalance a bleed solution that removes some iron. Moreover, galvanic interaction between pyrite (cathode) and chalcocite (anode) can substantially increase atmospheric leaching kinetics and efficiency (copper recovery).

Jan 1, 2016

By G. P. Demopoulos

"The recovery and separation of platinum-group metals (PGM) from primary and secondary materials currently attracts a lot of interest due to the high value of the metals and their increasing demand for high-tech applications. Thus, the traditional refining processes are gradually replaced by newer more efficient separation techniques such as solvent extraction and ion exchange. In this paper the classical and modern refining techniques are reviewed and the pertinent solution chemistry dictating proper processing strategies in each case is discussed. The technological advantages of the modern separation methods are emphasized and reference to the recovery of PGM from primary as well as secondary materials is given. INTRODUCTIONDue to their outstanding physicochemical properties, such as catalytic activity, conductivity and corrosion/oxidation resistance, precious metals now find extensive usage outside of the traditional jewellery and investment industries. The increasing use of precious metals in such areas as electronics and catalysis, as well as their increasing high value, has led to a growing interest in their recovery and separation from primary and secondary materials.Quantitatively the demand of platinum metals in the western world by area of application is described in Table I. Platinum and palladium represent 90% of the total demand, Rh and Ru 8% and the remaining is taken by Ir and Os. In terms of value the following were the average prices (US$/oz) of the metals in the second half of 1986: 500 Pt, 125 Pd, 1200 Rh, 650 Os, 400 Ir and 80 Ru. Due to these prices, exploration, mining, reclamation and refining activity were very high in South Africa, the biggest producer of Pt metals in the world, as well as in other areas: United States (Stilwater deposit), Canada (Sudbury, Marathon and Lac des Isles, Ontario; Kenly Lake, Quebec, etc.), Australia, Europe and elsewhere"

Jan 1, 1989

By Arnfinn F. Prugger, Fritz F. Prugger

"The Saskatchewan potash beds are overlain by a number of water-bearing formations. There are water zones in the footwall as well. These aquifers created difficulties during the construction of shafts to the potash beds at 1()(}() m depth, and they pose a continuous threat to the safe and efficient operation of potash mines in the province.The first shafts to be sunk in Saskatchewan encountered major problems during shaft sinking. Of the 17 potash shafts started in the province, five had major water inflows during shaft sinking or after production startup, and one was abandoned because of water problems. The biggest obstacle encountered during shaft sinking was a poorly consolidated sand-shale-clay-siltstone unit commonly called the Blairmore Formation, which occurs at a depth of about 500 m. The initial problems with shaft sinking were overcome in the 19605by using European methods of freezing and the installation of cast-iron tubbings or a double-steel lining through water bearing horizons.From the start of production in the early 19605, operators have been aware of the ever-present hazard of potential water inflows into mine openings from permeable units in both the hanging wall (carbonates of the Dawson Bay Formation which occur 15 m to 50 m above the mining level) and the footwall (carbonates of the Winnipegosis Formation which occur 50 m to 150m below). This awareness has been reflected in conservative over-all extraction rates and mining layouts specific to local conditions. In spite of this consciousness, a number of water problems have occurred in operating mines. These have resulted in everything from simple increases in expenditure to the shut-down of one mine in 1987.In this paper a history of water problems in the Saskatchewan potash industry is given, followed by a summary of measures that are now commonly used to avoid these problems. A description of each inflow event is given, and the attempt is made to analyze the causes of each occurrence. Based on what was learned f rom each event, suggestions are made to prevent future water inflows into potash mines."

Jan 1, 1991

By S. V. Burr

"IntroductionOne of the more puzzling geological enigmas, in the writer's opinion, is how rock can move sideways with respect to other rock. In the writer's study of regional northwest-southeast folding in North America (Burr, 1980), he may have found the answer to horizontal offset.Horizontal OffsetSideways movement or horizontal offset does not mean that the movement was, or is, horizontal. As indicated below, the actual movement may be at a high angle from the horizontal. However, it is the horizontal VECTOR, or offset, which is measured on surface by geologists. Vertical movements (thrust, normal, reverse) can be understood, as they involve blocks of rock , generally separated on four to six sides, which have been pushed up or subsided. Vertical faulting across dipping strata can produce APPARENT horizontal offsets. However, this thesis deals only with ACTUAL offsets.The ProblemFigure 1 is a plan view of a simple hypothetical horizontal offset. Three vertical dykes are intersected by a fault lineament. Two dykes exhibit no movement; the middle dyke has been offset a distance (a). Vertical faulting would have produced no horizontal offset. How can a horizontal distance (a) disappear or appear? Rock expands or contracts in infinitesimal amounts.SolutionThe map (Burr, 1980) shows the writer's interpretation of regional northwest-trending folds in Ontario. The writer made two observations about horizontal offsets during his thirty year study of these folds:1) All major horizontal fault lineaments strike at a high angle to the northwest fold axes. Many of the northwest-trending lineaments are fault s, but their movement is essentially vertical.2) Close to many of the known horizontal offsets (and several lineaments), there are areas where plunge reversals are so frequent and close together it is impossible to draw in all the fold axes at a scale of 1 inch = 4 miles, and, in the highly faulted Espanola area southwest of Sudbury, Ontario, all the indicated folds cannot be easily separated at a scale of 1 inch = 1 mile. The writer has observed folds less than 30 feet apart next to the strong Puskitamica-Chibougamau fault in northern Quebec."

Jan 1, 1982

By R. E. Lawless

The transportation challenge began with the need to move millions of tons of coal annually from Western Canada to Ontario. The paper will discuss the options which were available, the final mode selected and the economic trade-offs which were involved. It will outline the demands of unit train technology and the effect of transportation requirements on the other elements of the whole system.

Jan 1, 1979

By S. M. Taghavi, M. Halali

This paper investigates the possibility of zinc oxide production from zinc ore concentration residues, and also the effect of temperature, time and depth of bed on waste materials reduction percents. The results obtained show a significant increase of the reduction percent as a function of time and temperature. With increasing in depth of bed, reduction percent will decrease. Maximum zinc oxide percent in products was 93.5%.

Jan 1, 2004

Presentation Overview ?? Project Setting ? Project Context ? Challenges ?? Managing Commitments ?? Project Update ?? Maximizing Aboriginal Economic Participation in Resource Development PROJECT SETTING ?? Developed on the traditional lands of the Labrador Inuit, and the Labrador Innu ?? Courts have held that Aboriginal peoples in Canada possess special rights to traditional lands ?? Rights can include requiring resource developers to enter into Impacts and Benefits Agreements ?? Development agreement with Newfoundland and Labrador was required

May 1, 2004

By Takahiko Okura, Chiharu Tokoro, Shunta Shibuya

Copper concentrates bearing arsenic as enargite (Cu3AsS4) or tennantite (Cu12As4S13) have disadvantage on copper smelting environmentally and economically, so those concentrates should be treated decently. In this paper, some experiments of arsenic removal from several kinds of copper concentrates by heat treatment in an inert atmosphere were discussed. In this study, several samples in which arsenic contents varied 0.18 to 8.3 wt % were heated to the temperature range of 400 °C to 700 °C under argon gas flow during 1 hour. The heat residues and volatilized materials (V.M.) were analyzed by XRD, XRF, ICP-AES, XAFS and MLA to analyze residual concentration of arsenic and residual mineral composition. Experimental results showed that arsenic removal from copper concentrates advanced in 2 steps; at the temperature range of 500 ° C to 550 °C and of 550 °C to 650 °C, respectively. MLA analysis showed that a few of arsenic in enargite was removed by 550 °C heating and a majority of it was still combined with copper and sulfur as tennantite. On the other hand, arsenic in tennantite was removed almost completely by 650 °C heating. Furthermore, a particular type of arsenic mineral, such as Cobaltite (CoAsS) still remained after heating at 700 °C.

Jan 1, 2014

By Robert Voisey, Robert J. Spencer

"LynnGold's MacLellan Mine is located about 8 km south east of Lynn Lake immediately to the east of the Keewatin River (Fig. I). The property is accessible by an all-weather road, leading north from the provincial highway 391, which links with the Town of Leaf Rapids and the City of Thompson to the south.The ore body, as outlined in the original feasibility study, is expected to produce in excess of 9.3 x IQ6 gm of gold and silver over the next 5 years. However, the deposit is open to depth and exploration is continuing on and around the main zone and the many satellite deposits.The start of construction of the MacLellan Mine and mill was scheduled to phase in with the closure of the Fox copper-zinc mine located 48 km west of Lynn Lake. The majority of the employees from the Fox Operation were either employed at the MacLellan Mine or relocated to Sherrin's Ruttan Operation.GeologyThe MacLellan gold ore deposit is located on the northern section of the Lynn Lake Greenstone Belt known as the Rainbow Trend. This Trend is a 40 km gold bearing rock sequence extending both east and west from the MacLellan Mine. The southern section of these two east-west trending structures is known as the Johnson Shear, this is also gold bearing."

Jan 1, 1990

By M. D. Evans

"Note: The views expressed herein are those of the author, not of the Government of CanadaThe mining industry has a significant opportunity to capitalize on past learnings to build better social relationships. The industry’s relationship with society is critical and under pressure. Rising levels of public opposition and social conflict are already having material impacts on operations around the world. The industry has an opportunity to shape the future direction of this social engagement, build public trust, and proactively respond to a material risk to operations, but first it needs to better understand the nature of the challenges and the urgency of addressing them.RÉSUMÉ L’industrie minière a actuellement une excellente occasion de tirer profit de ses expériences antérieures pour établir de meilleures relations sociales. Les relations entre l’industrie et la société sont critiques et elles subissent de grandes pressions. L’escalade de l’opposition par le public et les conflits sociaux ont déjà des impacts physiques sur les opérations partout à travers le monde. L’industrie a l’occasion de façonner la future direction de son engagement social, d’accroître la confiance du public et de répondre de manière proactive à un risque matériel aux exploitations, mais elle doit tout d’abord mieux comprendre la nature des défis et l’urgence de les traiter."

Jan 1, 2015

By I. S. Zajac, Y. O. Oyediran, M. C. Robart

This paper presents an overview of the metallurgical work on the Strange Lake Alkalic Complex (SLAC), from historical development of the "Main Zone" to present day develoment of the "B Zone". The SLAC, originally discovered by the Iron Ore Company of Canada (IOC) in the northeastern Canadian Shield of Québec and Labrador, is one of the world’s largest deposits of rare earth elements (REE) including yttrium and high field strength elements (HFSE) including zirconium, niobium, and titanium. It is part of a Precambrian, post-tectonic complex of peralkaline granites which intruded along the contact between gneisses and monzonites of the Churchill Province of the Canadian Shield. Mineralization of interest at Strange Lake principally occurs within peralkaline granite-hosted pegmatite and aplite sheets and, to a lesser degree, within the host granites, particularly in intra-pegmatitic granites. The highest grade and metallurgically most favorable mineralization is in the upper, open pit mineable parts of the SLAC. Metallurgical development has been conducted under a number of mining companies, and various value metals have been targeted throughout the history of the deposit, including yttrium, zirconium, niobium, and rare earths. Historic processing routes tested have included ore beneficiation, atmospheric leaching, solvent extraction (SX), and metal precipitation. This paper also presents the metallurgical development supporting Quest Rare Minerals Ltd.’s (Quest) 2013 Pre-Feasibility Study (PFS) and 2014 Preliminary Economic Assessment (PEA).

Jan 1, 2014

By Didier Fohlen

Three Policy Shifts to enhance IFC?s Accountability ? Comprehensive and dynamic treatment of social, health, safety and environmental risks ?Covers a range of risks encountered by clients in emerging markets ?Framework to anticipate risks and to address them as they arise ?Includes community development, biodiversity, human rights ... ? Effective principles to guide an outcomes-based approach ?By clients and IFC ?Focus on broad community support and value-added sustainable development initiatives Enhanced governance, transparency and disclosure

May 1, 2006

By M. Rigaud, N. Zhou, K. Sankaranarayanane, X. Zhou

The effect of amount and type of dispersants on the rheological behaviour of bauxite-based low-cement castables has been studied in detail. The rheological properties: flow resistance and torque viscosity, as measured by a rheometer, are found to be strongly influenced by the amount and type of dispersants. In the present investigation, a mix containing sodium hexametaphosphate, at an optimal level, is observed to be theologically superior at the given experimental conditions.

Jan 1, 2004

By B. R. Maas

Processing material at a consistent rate through the continuous countercurrent decantation (CCD) thickeners presented a major bottle neck to unlocking additional value from one of the post-flotation streams at the Kansanshi processing plant. The manual operation of the thickeners making up the CCD train resulted in frequent imbalances and process upsets across units. The automation of CCD trains is notoriously tricky as the available manipulated variables are outnumbered by the parameters requiring regulation. The implementation of an advanced, auction-based, control philosophy to manage the movement of both slurry and solution inventory through the train addressed this parameter imbalance and lead to the stabilisation of the circuit. Since the commissioning of this control strategy: an additional 7 200 dmt/day (+36% throughput) of material can reliably be processed through the train, the number of monthly downtime events has reduced, and a saving of $354 000/month in reagent cost has been achieved. INTRODUCTION CCD operation Agitated leaching is a common method used in hydrometallurgy to extract a metal from its host ore. The host ore is initially finely ground to liberate the surfaces of the valued minerals and improve the kinetics of the leaching process. The ore is then contacted in an agitated tank with a lixiviant to dissolve the desired metal into the aqueous phase. The resultant slurry from the leaching process comprises of a solution pregnant in the metal salt and a barren ore. The first purification step taken after leaching is to wash the pregnant liquor solution (PLS) from the depleted ore. On the industrial scale, a set of between two to ten thickeners arranged in a countercurrent configuration is often used to carry out this separation (Perry & Chilton, 1973). The slurry is introduced at the head of the train and a wash solution at the tail. The two streams are pumped through each thickener countercurrent to one other. At each stage the residual PLS in the slurry is mixed and diluted down with the countercurrent overflow solution from the downstream thickener. The diluted slurry is fed into the thickener where the solids separate out through gravity sedimentation. The settled solids are channelled towards the underflow of the thickener by a rake mechanism and pumped downstream to the next thickener in the train. The outcome is the recovery of a PLS from the overflow of the lead thickener and a slurry of washed solids from the underflow of the tails thickener.

Jan 1, 2019