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By J. C. Loretto

"OPENING REMARKS Yesterday and today we have heard some very interesting papers on operating matters and some of you are probably wondering what we are now doing talking about Communications in Plant Design. Let me tell you! Before the techniques we have heard being discussed can be used, there has to be a properly operating plant. It is certainly a fact that many mineral processing plants achieve only limited success and a number of them can even be said to be failures. Some of you sitting here are probably living with operating problems that are clue to errors in the design.If the histories of these problem plants are examined, it will be found that in many cases, the necessary skills were available during the period of the plant design. There was extensive operating know¬ledge together with a full range of project expertise. Why then the failures? In a substantial number of cases it can be traced to the old, old problem of communications. As plants get bigger, money costs more and smooth startups become more important, it becomes less and less economic to fix up any design errors during plant operations.During our careers in mineral processing, nearly all of us will be involved in at least one plant design and I feel that it is as well if we understand some of these communication difficulties that can lead to a problem plant. There is little point in us being experts in mineral processing if the knowledge we have acquired doesn't somehow get incorporated into the plant.I would, therefore, like to present this short paper that mentions a few of the significant communication problems that can occur during the design of mining and mineral processing plants, together with some thoughts on answers to these problems."

Jan 1, 1973

By P. A. Gonzalez Contreras

Scorodite is considered as a secondary mineral formed from the product of weathering of primary minerals by chemical or biological reactions. In the case of biological scorodite formation, microorganisms mimic and accelerate what in nature takes a very long time, i.e. biocrystallisation. The goal of the biological scorodite formation is to form very stable arsenic crystals suitable for long-term and safe disposal. The biological formation of scorodite is a novel combination of biological oxidation, biocrystallisation, and proper bioreactor design to achieve the biological formation of scorodite crystals in one step. We have explored simultaneous biological arsenic and iron oxidation at 30ºC and at 70ºC leading to arsenic-jarosite phases and scorodite, respectively. As biologically formed scorodite crystals are very stable (TCLP < 1 mg/L As (V)), the risk of arsenic toxicity is minimized when leaching takes place. This process is suitable for arsenic concentrations above 0.5 g/l As achieving up to 20 mg/l As in the effluent. This biological scorodite formation system is a selfsufficient bio-oxidation system and therefore many new applications can be explored such as reprocessing of arsenic trioxide, orpiment or calcium arsenate to scorodite crystals for a stable and safe disposal.

Jan 1, 2014

By C. R. Larsen, R. G. Bradburn, A. L. Mular, B. C. Flintoff

"Following the acquisition of grinding- circuit data at Brenda Mines Limited for simulation purposes, various methods to mass balance the circuit were evaluated. Unfortunately, different answers were obtained for different balancing methods. A data-adjustment procedure was therefore developed. The procedure assumes that all ""best-fit"" criterion. A search is conducted with the minimum set of water masses and narrow size ranges of solids around the circuit (called search variables), which permit the computation of any of the measured data points. Search variables are used to calculate measured values for an objective function of the form: [ ] where W, is a weighting factor•, M1 is a measured value and M. is a corresponding . value calculated from search vanables. The best values of M, are those which minimize R. The above method is compared with others that have been utilized for mass balancing circuits."

Jan 1, 1976

By A. Banerjee, J. P. Weiler, J. Jekl, J. T. Wood, R. Berkmortel

"The work presented here is part of an ongoing project designed to develop predictive capabilities of the local mechanical properties, and thus, structural behaviour of a thin-walled high-pressure die-cast AM60B magnesium alloy component. This work focuses on developing correlations between process parameters and local microstructure. Numerical simulations of the die filling and solidification behaviour of the AM60B component were used to estimate local process parameters such as solidification rate, temperature gradient, filling velocity, etc. These estimated parameters were used to establish semiempirical correlations with measured VALUES (of the local microstructure measured in regions throughout the component of different solidification conditions. INTRODUCTIONHigh-pressure die-cast magnesium alloys are experiencing increasing use in structural automotive components. A strength-to-weight ratio comparable to steels and its ease of castability allow for these alloys to be utilized in such capacities as instrument panel beams, seat and door frames, and engine cradles, among others (Gjestland and Westengen, 2007). However, the current use of these alloys is limited due to variations in local mechanical properties. These local property variations restrict part designers to assume lower than actual properties, resulting in larger sections, thus diminishing the light-weighting advantages of magnesium alloys. If these local property variations could be predicted, part designers would be able to optimize die-cast magnesium alloy components and fully take advantage of the light-weighting capacity of these materials.The work presented here is part of an ongoing project aimed at developing predictive capabilities of the local mechanical properties, and bulk mechanical performance, from variations in local microstructure, and ultimately from local process parameters in die-cast magnesium alloys. This project, unique in its nature, is based upon the results determined from fifty sequentially cast AM60B magnesium alloy instrument panel beams provided by Meridian Lightweight Technologies (shown in Figure 1)."

Jan 1, 2012

By F. Samimi Namin

During the process of developing surface or underground mines, some sites are considered for dumping of surface soils, while others are applied to reclaiming surface and waste disposal. For each kind of overburden, whether it be waste rock, low-grade material, or process tails, a separate storage site is considered so that it becomes possible to transport or recover the overburden separately. Decision-making must be completed by means of a selection process which takes into account the best methods of alternative sets in order to achieve these goals. This decision- making involves many parameters that are inter-related in that changes in some parameters affect the others. There are many methods of decision-making, however, Fuzzy Multi-attribute Decision-making (FMADM) and its functions are studied in this paper. The advantages of this method lies in its theoretical background, formulation, revising capability, unlimited alternatives, and consideration of the counteraction of the different parameters upon one another.

Jan 1, 2007

By Shawn Healey, Ray Norcross

"Site IdentificationNew Britannia MineA 50/50 WX Gold Inc. - High River Gold Mines Ltd. Joint VentureTVX Gold Inc. is the OperatorLocationThe New Britannia Mine is located in the town of Snow Lake, Manitoba, which is situated between Flin Flon and Thompson, 420 miles north of Winnipeg.Brief Description of OperationNew Britannia Mine processes 2000 tonnes per day at an average grade of 4.5 g/t. Mill recoveries are currently 91 YO, accounting for forecast of 98,000 ounces for 1998.New Britannia Mine's mill complex incorporates conventional crushing, grinding and carbon-in-pulp technology. The design capacity of the New Britannia Mine mill is 1850 tonnes per day. The mill has processed upwards of 2300 tonnes per day, with no required upgrades.Gold recovery averaged 89.8% for 1997 compared to the planned 87% recovery expected from projected metallurgical test work. Year to date recovery mid December 1998 stands at 91.1 %Cash costs for the 1998 year to date were down to U.S. $221.49 per ounce, down 12% from the 3rd quarter of 1997. Milling costs for 1998 YTD were at Cdn. $9.38 per tonne and Cdn. $73.50 per ounce.Geology - (Orebody Description)The Snow Lake gold deposit is located within the Aphebian Flin Flon / Snow Lake Greenstone belt. This belt is composed of an assemblage of poly-deformed volcanosedimentary supercrustal sequences intruded by pre and sin tectonic ultra mafic and mafic intrusions and sin to post tectonic granitoid.The principal gold bearing rock at the New Britannia Mine is made up of quartzcarbonate material in sequence of basic and acidic volcanic rocks contained within a shear zone. The ore itself is gold associated with the sulphide mineral arsenopyrite and contains some pyrite, pyrotite, plus chalcopyrite. Proven and probable reserves at December 31, 1997 were at 4.04 million tonnes at 4.6 g/t and underground exploration continues to confirm the extension of the ore zones to depth."

Jan 1, 1999

By Lyne Côté, Jose Adante

"The Caribou underground mine, 50 km west of Bathurst, the Restigouche open-pit mine, another 30 km west and the concentrator located at the Caribou mine site resumed operations in July 2007 after a nine year shutdown. The Caribou operations achieved commercial production on Jan 1. By June, 2008, all metallurgical targets had been achieved or surpassed with the production of lead and zinc concentrates assaying approximately 50% Zn and 45% Pb respectively with recoveries exceeding 80% for Zn and 70% for Pb.The deposit features very fine-grained massive sulphide mineralization, which in the past has proven difficult to process. ISA Mill Ultra Fine Grinding Technology in combination with conventional flotation technology is used to process these complex oresSeveral modifications arising from experience gained from past operations, an extensive research project at Lakefield Research and post startup flow sheet and reagent alterations have been employed to achieve this break through performanceThis paper describes the design, start up and optimization of the Caribou operations including the many challenges faced including the flotation of mineral particles with K80s ranging from 35µm to 8µm.HISTORICAL BACKGROUNDThe Caribou massive sulphide deposit was discovered by Anaconda geologist Cam Cheriton in 1959. Anaconda initiated an extensive underground exploration and discovered a super gene copper blanket which was developed into a small open-pit mine-mill operation that ran from 1970 until the depletion of the copper ore in 1974. East West Minerals, an Australian public company, purchased the mine in 1986 and operated for only seven months producing a single bulk lead-zinc concentrate. In 1995, Breakwater acquired the Restigouche Open pit and Caribou underground deposits. Breakwater began milling operations in July 1997 but Caribou Mine failed to commercialize production, and the company decided to shut it down in August 1998, because of declining metal prices. The mill was plagued by mechanical and design problems, but deficiencies in metal recoveries prevented the operation from reaching desired levels."

Jan 1, 2009

By T. Lux, H. -J. Krassnig, I. Filzwieser, E. Hecker, R. Degel, A. Filzwieser

Non-ferrous metals find their applications in smartphones, tablets and computers. These materials with their particular properties are the basis of our modern life. SMS group is well prepared for this huge market and for growing future challenges. A large contribution here is the new joint venture PolyMet Solutions that was founded by SMS group and Mettop, an Austrian engineering company, with the objective to develop new technical solutions for the primary copper production lines as well as for non-ferrous metals starting with the primary smelting of concentrate and ending with the electrolysis. PolyMet Solutions provides the process know-how whereas SMS group supplies the plants and equipment and Mettop the key components. SMS group and Mettop also cooperate in the field of tankhouse technology. Together with Montanwerke Brixlegg AG, Mettop has developed together with a parallel flow technology (METTOP-BRX Technology), allowing a current efficiency of above 98 % at a current density of 420 A/m², which is a milestone in copper electrolysis. For the secondary copper production route, SMS group and PolyMet Solutions developed an innovative refining furnace (PolyRefine) for the smelting and refining of copper scrap. The refined copper is directly charged to the Contirod line to produce copper rods and wires. The innovative cooling solutions of SMS and PolyMet Solutions come into play where furnaces have to stand the highest loads and stresses, for instance in areas of very high temperatures or temperature fluctuations, aggressive exhaust gases and slags, or at critical spots such as taphole areas. Custom-tailored cooling systems for furnace vessels make sure varying loads are compensated in a targeted and effective manner. The solutions include air cooling, spray cooling, cooling technologies with integrated copper elements such as CFM (Composite Furnace Modular) cooling systems, plate and finger coolers. The major innovation in the field of furnace cooling is the ILTEC (Ionic Liquid Cooling) Technology which paves the way for increased plant safety. This revolutionary, patented cooling technology is jointly marketed by Mettop and SMS group. It permits water-free cooling to be implemented and thus makes operation safe wherever it is applied. INTRODUCTION Non-ferrous metals or NF metals are changing the world. There is no modern industrial sector that can do without these valuable metals. Non-ferrous metals find their applications in smartphones, tablets and computers. These materials with their particular properties are the basis of our modern life. The importance of the non-ferrous metals market is reflected by two figures. In 2018, the production of non-ferrous metals was worth more than 237 billion Euros. This contrasts with 255 billion Euros of the value of iron and ferro- alloy production in the same year (International Organizing Comittee for the World Mining Congresses, 2018). Hence, the NF metal industry is almost as important as the iron and steel industry. SMS group is well prepared for this huge market and for growing future challenges. A large contribution here is the new joint venture PolyMet Solutions that was founded by SMS group and Mettop, an Austrian engineering company, with the objective to develop new technical solutions and to enhance customer value. The prices of nearly all metals have come under pressure during the past few years. Therefore, competitive technologies are regarded a crucial factor to achieve success in this critical market situation respectively to stabilize the market position.

Jan 1, 2019

By G. Belzil, F. Robichaud, M. Fullam

ABSTRACT The Goldex mining and milling complex is operated by Agnico-Eagle and is located in the Abitibi greenstone region of northwestern Quebec, Canada. Commercial production started in 2008. Average gold recovery is 93.5% with approximately 68% of gold recovery coming from the gravity circuit. During the first three years of production, three gravity audits were carried out to optimize performance of the gravity circuit. This paper presents results of the audits and the development of a model linking gravity and overall gold recovery, and outlines improvements made to increase gravity performance and reduce operating costs.

Jan 1, 2013

By V. G. Papangelakis, M. Cheung, M. Dry

The high pressure acid leaching of laterite was modelled and simulated using a combination of two commercially available software packages, namely Aspen Plus 11.1 and the OLI Stream Analyzer. New kinetic parameters for the acid-controlled metal dissolution and precipitation reactions at temperature were first determined from previous experimental data on the leaching of limonite. A grain model with cylindrical pellets was used to model the solid-liquid dissolution reactions. Precipitation reactions were modeled via aqueous equilibrium chemistry. A dedicated thermodynamic database previously developed at the University of Toronto was used in conjunction with the OLI software to model the solution chemistry and calculate the concentration of hydrogen ions in solution at the leaching temperature. Mass balances were handled by Aspen Plus. The simulation gave good predictions of nickel dissolution under industrial and laboratory conditions, for the dissolution of limonite and limonite/saprolite blends. Computational

Jan 1, 2005

By D. H. Stonehouse

"ALTHOUGH final statistics are not yet available concerning Nova Scotia' s mineral production for 1958, it is estimated that the value will be slightly lower than that of 1957. In making this statement it is but fair to say that one year ago a reduction in mineral value was also forecast (for 1957 as compared with 1956) and final figures from the Dominion Bureau of Statistics ($68,058,743) indicated, instead, an increase of $2,000,000 over 1956. However, 1958 did bring problems to the industry which would indicate a drop in production value. The estimates figure for 1958 is $64,000,000. COAL Coal production came from 28 mines, 5 less than were operating since 1957. There were 5,269,896 tons of coal produced by 1,978,512 man-days' labour, for a tons per man-shift of 2.66 (0.05 higher than during 1957) or an increase of 1.9 per cent over the 1957 all-time high for this Province. This record has been established as a result of concentrated efforts to mechanize the coal mines of the Province, and it is hoped that it will be bettered during 1959. Collieries which showed some production for 1957 and none for 1958 were the McGregor at Stellarton, the Franklin at Sydney Mines, the MacLellan, the Rose bank No. 2 and the Rose bank No. 3 at Inverness."

Jan 1, 1959

By J. Duncan Crone

"A test surface Pulse EM(PEM) survey over a plunging massive sulphide lens, located in the Snow Lake area of Manitoba, has shown that it is possible to detect the body to a depth of 300 metres. Another surface survey in the Athabasca basin of Saskatchewan, clearly outlined a large, basement graphitic zone below 450 metres of sandstone cover. Deep detection of these conductive bodies was achieved by energizing large volumes of ground with a strong transmitted EM field. Such large fields also energize all other conductors present in the exploration area. Both of the above survey results indicate that more than one conductor is present. In such cases, detailed field coverage is required for accurate interpretation, and interpretational procedures that assume simple geometrical shapes should be applied with caution. In all cases geological and geophysical information should be coordinated in detail. The first test drill hole still has a high risk of missing the deep conductive body and two or three holes should be budgeted per target.Borehole Pulse EM surveys are now routinely used to help zero in on deep conductive targets. They are also proving effective in development drilling programs by outlining the edges of conductive bodies. The results of surveys from northern Quebec illustrate how they may provide more accurate shape and tonnage estimates."

Jan 1, 1985

By R M. Ennis, J. C. Botham

This paper is one of a series pre-pared to study the role of fuels and reductants in metallurgical processes, especially from the viewpoint of Canadian requirements. The object of these studies is to provide a reason-ably authoritative interpretation on the interrelation of fuels in light of the considerable changes that have taken place in the Canadian energy field during the past few years. Previous papers in this group have dealt with the problem generally, and specifically in terms of the development of the iron and steel industry of Western Canada. These latter papers, presented at the Symposium on Iron and Steel in Western Canada held in Edmonton, Alberta, on September 8-9, 1959, surveyed the ferrous processes of interest for use in Wes tern Canada, especially with regard to solid fuel requirements. At that time it was evident that there was a need for a similar study of the fuels aspect of the non-ferrous metals industry.

Jan 1, 1961

By P. M. Dranchuk

"SINCE their inception, the mineral industries have, from time to time, been confronted by various and sundry problems. These have been identified, attacked and solved by means of a slow methodical process peculiar to these industries. During the past decade, these industries have experienced increasing difficulty in attracting and retaining an adequate supply of manpower. This poses a situation which seems to be unlike those that came before it in that it appears to be immune to those methods of attack which were successful in the past. Despite various attacks upon the problem, its seriousness appears to be increasing at an increasing rate. The point has now been reached where the President of AIME recently expressed the opinion that this is the most serious problem facing these industries at this time (1). Another observer has gone so far as to state, ""Given the motivation and the determination, the crisis in mineral education in Canada, can, in time be met. But it will take a generation if we Start DOW (2)"".Part of the difficulty arises out of the identification and assessment of the problem itself. For, although the manpower shortage has been developing over a fairly long period of time, there still appears to be no unanimity concerning its seriousness and the nature of the threat which it poses. Some observers continue to maintain that the current situation is not new at all, but is merely the reappearance of something old which is cyclic in nature. They observe that in the past there were numerous periods where the mineral industries encountered manpower shortages but that, in each instance, the situation eventually rectified itself. Furthermore, they draw attention to the fact that the current problem is not confined to the mineral industries but that in fact all industries are experiencing an increasing manpower shortage. They are therefore confident that if left alone the present problem will eventually disappear."

Jan 1, 1967

By Ruan Chi, Zhenyue Zhang, Zhengyan He

In order to understand what governs the leaching of exchangeable rare earth (RE) and impurities and enhance the RE leaching process, the effects of the concentration of ammonium sulfate, pH and leaching temperature on the migration of RE and aluminum (Al) during the leaching of weathered crust elution-deposited rare earth ore was studied. The elution curves for ammonium ion (NH4 +) were also studied to reduce the consumption of the leaching agent. It was found that a high concentration of leaching agent can enhance the leaching process of RE and Al, reduce the breakthrough volume of NH4 + and more rapidly obtain the equilibrium of NH4 +. However, excessive leaching agent can both increase the cost and the burden on the environment. There is almost no variation on the elution curves of RE and Al in the pH range of 4-8 and control of the pH of the leaching agent can be omitted. It is better for the leaching work to be done in summer since higher temperatures can enhance the RE leaching process and improve the use ratio of ammonium. Using 0.1 mol/L ammonium sulfate for leaching 250 g RE ore, 95.42% RE extraction can be obtained when the volume of leachate is 102.6 mL. At this moment, only 18.17% of NH4 + is used to exchange RE and 49.22% of NH4 + is left in the leachate that can be reused as leaching agent by replenishing ammonium sulfate. The results of our studies can provide theoretical guidance for high efficiency and low consumption exploitation of RE ores.

Jan 1, 2016

By G. H. Babcock, D. A. Knight, V. G. Medina

"Production commenced at the Golden Sunlight Mine in 1983 and at Kidston Gold Mine in 1985. These projects were both constructed under the management of the Placer Dome Inc. (Technical Services) group of Vancouver, B.C.Golden Sunlight uses a conventional rod mill/ball mill grinding circuit while Kidston uses a SAG /ball mill, and later on, SABC circuit. Since the hardness of the ore and the fineness of the primary grind in both mines are about the same, a meaningful cost comparison can be made. The comparison is made on the basis of capital and operating costs.The result of this study indicates that a significant capital cost savings can be achieved in favour of the SAG /ball mill circuit when the ore is amenable to semi-autogenous grinding. With a good maintenance program, the operating cost for the SAG /ball mill circuit could also be lower that the conventional rod mill/ball mill circuit.HISTORYGolden Sunlight MineGolden Sunlight is a 5 530 t/d gold mine located near Whitehall, a small town 60 km east of Butte, Montana. Originally optioned by PDI U.S. in 1958, the development of the property waited until 1981 when economic conditions became favorable for the project to proceed.Semiautogenous grinding tests were conducted during the final stages of the feasibility study. The hard near surface ore was not quite amenable to semi-autogenous grinding. The best result produced from a series of tests using a 1.83 m diameter mill was a semiautogenous work index of 39. This is substantially higher than the 22 Bond work index of the sample used in the testwork. A conventional SAG/ball mill circuit for this ore will be extremely inefficient, and for this reason, this circuit was rejected in favour of a conventional rod mill/ball mill circuit."

Jan 1, 1991

By J. Shanks

In 1920 the writer presented some notes, embodying his experience with storage-battery locomotives as main under-ground haulage-motors at Brazeau collieries. (1) Since that date these motors have stood up well to the test of maximum output and heavy overloads, having accomplished all that was expected of them. The notes presented in 1920 gave a brief description of the conditions under which these motors were working at Brazeau collieries, also the cost, per ton mile, of operating them. The cost per ton mile has since then been appreciably reduced, by working the locomotives nearly to capacity and under more ideal haulage conditions, on both shifts. It is not the intention of the writer to repeat what was written in 1920, but rather to give members the benefit of his experience in operating different types or designs of locomotives; to draw their attention to the drawbacks of some designs, and to the improvements made in some of the more recent storage-battery locomotives put on the market, as regards efficiency, upkeep, and safety. Because of their flexibility storage-battery locomotives have advantages over any other type of haulage, where grades are suitable to their use. The number in use in the mines in the United States has increased enormously during the past few years, and this method of haulage is, at the present time, attracting the attention of British and Continental mining engineers.

Jan 1, 1924

By Jing Li, Weiqiang Lai, Joe Zhou, Jiezhen Ma, Shuibo Chen, Ashele Copper Company, Feng Gao, Guofu Feng

"Copper-zinc ores often contain gold and silver, which can be recovered into copper concentrate by flotation as by-product. The challenges for operations that produce copper, zinc, gold and silver are the separation of copper and zinc and the low grade of precious metals. Ashele copper-zinc ore in north China contains 2.38% Cu, 0.69% Zn, 0.21 g/t Au and 18.10 g/t Ag and the plant produces copper and zinc concentrates, with gold and silver being recovered into copper concentrate. Copper occurs mainly as chalcopyrite and Zn occurs as sphalerite. Copper is well recovered with a recovery of over 94%. However, the recovery of Zn is substantially low (around 50%) due to fine grain size of sphalerite. In addition, gold recovery is much lower than expected and only 33% of gold in the flotation feed was recovered. The grade of gold in copper concentrate is also lower than the required payable grade (1.0 g/t). To determine the cause for lower Zn and Au recoveries, a plant survey program was conducted on the operation. The information acquired shows that the loss of Zn was mainly in the copper concentrates (accounting for approximately 38% of the head assay); of which, 24% was liberated, 8.5% was associated with chalcopyrite and 4.6% was associated with pyrite, indicating that the separation of copper and zinc was the main cause for the Zn loss, with liberation being the second cause for Zn loss. Future effort in improving Zn recovery should be focused on the separation of zinc from copper. Gold in the ore occurs as both microscopic gold and submicroscopic gold, accounting for 36% and 64% of the head assay, respectively. Microscopic gold occurs mainly as native gold and electrum; it is relatively coarse with a grain size of 10 to 240 µm and a large portion can be recovered by gravity. Submicroscopic gold was mainly carried by pyrite (accounting for 38%), and to a less extent, by tennantite (15%) and chalcopyrite (10%). Gold in sphalerite is nominal (1%). It is suggested that more coarse gold and tennantite be recovered and a gold recovery increase can then be achieved to obtain a copper concentrate with over 1.0 g/t Au through flowsheet optimization. Gravity concentration should be investigated and may be worth added into the existing flowsheet to maximum the gold recovery and grade.INTRODUCTIONCopper-zinc ores containing gold and silver is a subtype of polymetallic sulphide ores. Unlike porphyry copper sulphide ores and iron-oxide copper-gold ores, this type of ores often contains substantial amounts of zinc and lead. Polymetallic sulphide ores are mainly distributed in Canada, such as at the LaRonde and Horne deposits. Other examples include Mt. Morgan in Australia and Boliden in Sweden. Globally, production and reserves from gold-rich VMS deposits account for 1370 t gold. This is equivalent to 1% of the world production and reserves, whereas the Canadian total for gold-rich VMS deposits is 870 t, representing close to 10 % of Canadian production and reserves (Gosselin & Dube, 2005a, 2005b). Flotation is the principal process for processing the copper-zinc sulphides ores, for subsequent smelting, roasting, or hydrometallurgical treatment. Oxidized copper-zinc ores can also be processed using leaching technology. For example, at LaRonde operation (a Cu-Zn-Pb ore containing 3-4 g/t Au and 60-100 g/t Ag) the flowsheet consists mainly of a copper flotation circuit and a zinc flotation circuit followed by a cyanidation process of flotation tails. The precious metals are recovered with copper concentrate, zinc concentrate and cyanidation of zinc tails via Merrill Crowe precipitation (Zhou et al., 2005)."

Jan 1, 2016

By P. Coursol

The Noranda Reactor Process (NRP) has been in operation now for more than 30 years and this mature process has attained a high level of performance. The NRP at the Home Smelter of Xstrata Copper treats a wide range of feed materials and a thorough knowledge of both process control and smelting physico-chemistry has been beneficial to help meet the required plant flexibility. In this regard, some level of predictive knowledge related to slag chemistry, in particular, the liquid and solid phases such as spinels or olivines, has been found to be beneficial. In the last decade or so, the availability of commercial thermodynamic modeling packages, such as Factsage1m have been utilized with advantage to help the plant optimize slag chemistry and minimize problems from difficult slags, for example, those the could arise from undue feed variability. This paper illustrates the application of this software in examining a range of operating parameters such as: %Fe in product matte, the %Fe/%Si02 ratio in the slag, the levels of minor slag components including CaO, Ah03, ZnO, and MgO, and the level of oxygen enrichment on the operating conditions of the NRP. The slag composition boundaries at the conditions affecting magnetite control and solid magnetite/other precipitated solid phases, as well the conditions influencing the slag liquidus ranges of NRP slags are also discussed with respect to the overall process chemistry.

Jan 1, 2007

By Yves Gagnon, Nicole Gauthier, Daniel Kelly, Michel Rocheleau

"The Larder Lake-Cadillac Tectonic Zone in Rouyn-Beauchastel area (a 20 km long segment) contains distinct lithotectonic units bounded by artastomosing or sub-parallel shear zones. The gold deposits in the area are located within highly strained portions of E-W striking shear zones. The ore-zones are structurally controlled disseminated and vein-type lodes. They are spatially related either to megascopic z-shaped folds which refold E-W shears, or to areas of intersection between E-W shear zones and late NE-striking faults. Several ore bodies are enclosed within ultramafic rock units or at their contacts with adjacent units. All the lenses are elongated down dip and distributed, both loterally and vertically, ""en echelon"" . The ore zones tend to decrease in size and number away from the hinge zone of the megascopic z-shaped folds.Two main styles of mineralization are recognized at the Astoria deposit and at for most of the deposits in the Rouyn-Beauchastel segments a discontinuous ""Carbonate Ore"" and a more continuous, albitic sulphide-bearing ""Flow Ore"" (terminology used at the Kerr Addison mine).The typical ""Carbonate Ore"" zones are found within strongly arbonatized blocks bounded by conjugate late NE or NNW-striking fralls. The carbonatized blocks display features characteristic of llrittle to brittle-ductile deformation developed in shear zone system. Vein systems in the ""Carbonate Ore"" occur within shear fractures(D R)tension fractures (T), or within brecciated rocks adjacent to NS llrilcing faults. The ""Carbonate Ore"" zones are displaced by numer IU lole E-W, NNE, NW and N-S faults.The ""Flow Ore"" zones are found within predominantly ductile portions of E-W shear zones. The sulphide mineralization is finely disseminated and regularly distributed within mylonitic foliation or associated with veins and veinlets sub-parallel or oblique to the mylonitic foliation, in which case the mineralization is coarser grained. The gold mineralization is a late Archean event postdating the formation of the penetrative fabric, and synchronous with the end of the dextral oblique-slip motion."

Jan 1, 1990