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By M. J. McLeod, S. Watters, G. G. Lutes, S. Castonguay

"Gold-bearing mineralization at Anomaly A occurs in polydeformed Ordovician turbidites of the Kendall Mountain Formation of the St. Croix belt in southwestern New Brunswick, and is hosted by WSWtrending, shallow-dipping, brittle-ductile high-strain zones associated with the latest stage of the second of four regional deformation events. Gold-bearing syn-deformational stockwork, massive, and multiply brecciated quartz-sulfide veined zones form irregular pods and sheets up to several meters thick, which contain arsenopyrite, pyrrhotite, pyrite, stibnite, and a variety of rare minerals that are gold-bearing. Mineralized zones are enveloped by locally auriferous, weakly to intensely altered wall rock. Vein paragenesis includes: (1) early (pre- to syn-D2) quartz-chlorite veins that are largely the product of migration of quartz by pressure solution; (2) crosscutting, multiphase, vuggy quartz-sulfide veins that contain most of the gold and are interpreted to be structurally controlled; (3) late, crosscutting, nondeformed, non-gold-bearing veins containing laumontite, chlorite, muscovite, quartz, fluorite, and base metal sulfides. Carbonate-poor alteration associated with zones of gold mineralization is lithology-specific, and appears to reflect overprinting of multiple events. Major elements removed during alteration include Si, Na, Mn, and Mg. The minor and trace elements removed include Co, Li, Sc, and possibly Sr, Ni, and Zn. Minor and trace elements added include Au, Ag, As, Sb, S, and possibly F, Cu, Pb, and Zr. On the basis of proximity, time constraints, and a similar ore mineral assemblage, gold mineralization at Anomaly A is interpreted to be a distal equivalent of the intrusion-related gold mineralization at the nearby Clarence Stream Main zone deposit. La minéralisation aurifère de l’Anomalie A se trouve dans des turbidites Ordoviciennes polydéformées de la Formation de Kendall Mountain, dans la ceinture de Ste-Croix du sud-ouest du Nouveau Brunswick, où elle est contenue dans des zones de déformation fragile-ductile à faible pendage de direction OSO associées au dernier stade du second de quatre épisodes de déformation régionale. Les zones aurifères syn-déformationelles se présentent en forme massive, de stockwork, ou de veines de quartz-sulfure bréchifiées à répétition formant des lentilles irrégulières et des couches de plusieurs mètres d’épaisseur contenant de l’arsénopyrite, de la pyrrhotite, de la pyrite, de la stibine, ainsi que divers minéraux aurifères rares. Les zones minéralisées sont entourées d’une enveloppe de roches faiblement à intensément altérées, localement aurifères. La paragénèse des veines comprend : (1) des veines précoces de quartz-chlorite (pré- à syn-D2) qui sont principalement le produit de la migration du quartz par solution-pression; (2) des veines polyphasées de quartz drusique et de sulfures contenant la plus grande partie de l’or, celles-ci sont considérées comme étant sujettes à un contrôle structural; (3) des veines tardives stériles, sécantes et non déformées contenant de la laumontite, de la chlorite, de la muscovite, du quartz, de la fluorite et des sulfures de métaux usuels. Les zones de minéralisation aurifère sont associées à une faible altération en carbonate contrôlée par la lithologie et semble résulter de la superposition d’événements multiples. Les éléments majeurs perdus durant l’altération sont le Si, le Na, le Mn et le Mg. Les éléments mineurs et traces perdus durant l’altération sont le Co, le Li, le Sc et possiblement le Sr, le Ni et le Zn. Les éléments mineurs et traces enrichis comprennent l’Au, l’Ag, l’As, le Sb, le S et possiblement le F, le Cu, le Pb et le Zr. Étant donné sa proximité géographique, les contraintes temporelles et les similitudes de leurs assemblages minéraux, la minéralisation aurifère de l’Anomalie A est interprétée comme un équivalent distal de la minéralisation aurifère associée aux intrusions du gisement avoisinant de la zone principale (Main"

Jan 1, 2008

By John D. Campbell

"IS YOUR MANAGEMENT CONTROLLOOP FUNCTIONINGMineral processors make use of hundreds of control circuits in their mills, process plants, smelters and refineries, to optimize throughput and recovery and minimize cost. This afternoon, I would like to discuss what is probably the weakest circuit in any mineral processing operation - the management control loop.In their recent book ""The Winning Streak"", Goldsmith and Clutter describe extensive research on unsuccessful companies. They conclude that ineffective control, which does not immediately identify the problems, is one of the main failings of unsuccessful companies.We will look at the three key components of control which, from the manager's point of view, ensure that the loop is complete. These three are:• measuring what's happening,• assessing its significance, Rnd• altering performance.If we compare management control to process control as shown in this first figure, ""We see that parameter sensing by the analyzer in a process circuit is analogous to performance monitoring by management in a responsibility centre. The analyzer senses temperature, pressure, flow, weight or some surrogate indicator such as colour to indicate ion concentration. For manage1nent, the performance to rnonitor is dependent upon the objectives of the responsibility centre, and the key factors which affect these objectives."

Jan 1, 1985

By Karl J. C. Harries

"12.1. NO DEPRECIATION/GAAPAll calculations and computations relating to the Royalty shall be carried out in accordance with generally accepted accounting principles consistently applied to the extent that such principles are not inconsistent with the provisions of this Schedule and the agreement attached hereto, it being specifically agreed that nothing herein contained shall permit, or be construed to permit, the Operator to deduct any amount for depletion, depreciation, amortization or any deduction that represents a non-cash outlay.Comment: In cases like net profit royalties where recoupment of prior expenditures is permitted, care should be taken to avoid any implication that depreciation may also be taken. It is only logical and equitable that Property Owners should not be permitted an apparent ability to “double dip” with respect to deductions. A provision like this example should accomplish the task. It will be noted that the example specifically contemplates that the negotiated arrangements will prevail over any requirements of GAAP. Accordingly, if the parties agree to an unusual formula for recoupment, it will not be set aside to accommodate GAAP requirements. Under GAAP, revenues and expenditures are accounted for on an accrual basis. In addition, it specifically prohibits the taking of non-cash deductions, which is in keeping with the concept of recoupment.Although in some ways the example states the obvious and could be considered redundant, its presence, especially in provisions contemplating recoupment, makes it clear to the financial people that there may well be some variations from normal practices dictated by GAAP, while at the same time confirming the availability of GAAP to fill any voids.The accounting profession often makes the caveat that application of GAAP is an “art”, not a “science”. GAAP do not provide a cure-all and can create problems that will have to be addressed. For example, GAAP contemplate that asset costs are to be reduced by investment tax credits, which can cause a problem for a payor with more than one mine."

Jan 1, 2003

By C. Pelley, A. Piche

"The Canadian mining industry faces the prospects of a severe shortage of graduate mining engineers over the next decade. This arises from three factors: first, a growth in industrial activity; second, the average age of company engineering and management staff; and third, the reduced number of students in engineering faculties around the world. This paper aims to identify the critical factors underlying the trend of inadequate recruitment into higher education for mining and to examine means of alleviating the problem.This paper is based upon surveys of potential and current students and graduate mining engineers from four mining schools. An attempt is made to understand institutional and industrial images, career prospects and what is required to attract enough high-calibre young people into mining education over the next decade.IntroductionThe mining industry has started to experience a severe shortage of graduate mining engineers which is likely to persist and even worsen in the short- to medium-term.This arise s from three principal factors:1. a recent and strong growth in mining activity, which surpasses that experienced through the 70s, before the recent international industrial recession; .2. an increasingly older average age of mine engineering employees, at least in the industry's larger companies; and3. problems associated with maintaining adequate mining undergraduate recruitment levels ."

Jan 1, 1989

By Zachary Mayer

Agenda ? Kidd Mine ? Background ? Problem & Opportunity ? Challenges associated to depth - Production Rates - Productive Work Time - Operational Delays - Transfer Levels - Mucking Time - Impact on Hoist ? LHD Automation ? Sandvik AutoMine Lite ? Expected Benefits Kidd Mine - Background ? Located in Northern Ontario, Canada ? Underground base metal mine operating since 1966 ? Total 148 Mt mined (2.31% Cu, 6.08% Zn, 75 gpt Ag) ? 2.35 Mt/Y from stopes as deep as 9500 ft (2.9km) below surface ? Mining method: blasthole open stoping ? Mine/Mill: 1263 employees and contractors ? 2012 National John T. Ryan Safety Award

Aug 1, 2013

By J. P. Mogan, E. D. Dainty, A. Lawson

"The toxicity reduction of emissions from two diesel engines by the emulsification of water into fuel oil was investigated to determine the applicability of such systems to underground mining machinery. . The engines studied were: 1) the Deut; F6L7J4, four-stroke, air-cooled, 6-cylinder, V-configuration, indirect-injection (IDl) engine, and 2) the Detroit Deisel Allison Division 8V7JN, two-stroke, water-cooled, 8-cylinder, V-configuration, direct-injection (Dl) engine.The application of emulsified fuel treatment to the two-stroke engine did not prove to be practicable. In the case of the Deutz engine, however, substantial benefit resulted. For a modest J5 per cent water content in the fuel and an injection timing of24° BTDC, approximate reductions of40 per cent in the concentrations of both particulate matter and nitric oxide (NO) were produced. These reductions were accompanied by insignificant changes in other toxic constituents. The net result was an approximate 30 per cent reduction in the over-all exhaust toxicity for typical LHD operation as assessed by the Health Effects Index criterion. This toxicity reduction represents a significant advance from the points of view of an improved underground environment and/or reduced ventilation costs."

Jan 1, 1981

By René Lefebvre

Numerical simulations of the physicochemical processes related to acid rock drainage (ARD) in the Sugar Shack South rock pile of the Questa Mine were performed with the TOUGH AMD simulator. The objectives were to 1) identify the main processes responsible for observed present-day conditions, 2) provide an estimate of gas phase humidity transfer, and 3) give a preliminary indication of the potential impact of closure involving the installation of an alluvial soil cover. Modeling results indicated that the mine rock geometry (thin layers placed along steep mountain slopes) favors the onset of strong thermal air convection. Simulations also indicate that resloping the piles would not significantly reduce convection and oxidation. For simulation purposes, a potential cover with the permeability range of a local alluvium was investigated and found to be of questionable effectiveness since its permeability can exceed the value of 3x10-13 m2 required to prevent thermal air convection and reduce ARD.

Nov 1, 2002

By Ian Thomson

The Social License to Operate ? We are operating in an era where social license in the resource industry is as important ? if not more important ? than mineral potential ? Concept proposed by Placer Dome executive Jim Cooney in 1997 as essential requirement for the future survival of the mining industry ? ?You don?t get your social license by going to a government ministry and making an application or simply paying a fee? It requires far more than money to truly become part of the communities in which you operate.? Pierre Lassonde, President of Newmont Mining Corporation (2003). What it is ?Granted by the local community ? Intangible, informal, non-permanent ? Has to be earned and then maintained ? Defined as ? Ongoing Acceptance (a lower level) ? Ongoing Approval (a higher level) ? Expression of the quality of the ?relationship?

Aug 1, 2013

By K. Leung, J. E. Udd, L. B. Geller, F. Kitzinger

"Sixteen miners died tragically at the Paymaster gold mine in Timmins, Ontario, in February 1945 when a badly corroded hoist rope broke. The investigation of the Royal Commission that followed arrived at a number of recommendations (The Legislative Assembly of Ontario, 1947) aimed at avoiding future disasters of this kind. One consequence was the development and legislated use in Canada, several decades ago, of powerful electromagnetic (EM) instruments for the non-destructive testing of mine shaft wire ropes. The authors have been involved for many years in the design, production, and testing of EM instruments (Geller and Udd, 1990, 1992; Geller and Kitzinger, 1991; Geller et al., 1992). Since the mid-1990s, particular attention was paid to the design and operational results obtained from the computer controlled portable MagnographTM II wire rope tester (Geller et al., 1995, 1998).In the present paper, the authors summarize further hardware- and software-related developments of this instrument. Further, an account is given of the results obtained from the most recent design known as the Perma- ScanTM testing system. This is also a computerized dual-function system. In it, however, the sensor head is designed primarily, if not solely, for permanent installation and for remotely controlled operation. This represents a basic departure from traditional designs, which were intended for ad hoc temporary installations. The remote-controlled instrument described in this paper has now been in operational use for more than four years."

Jan 1, 2003

By C. L. Popp

The scope is to address issues confronted by parties in the mining industry such as: Mine planners, survey and engineering departments, field teams and subcontractors. Describing approaches and best practices for assembling a project team to identify and create modeling requirements and to implement beneficial results. 3D Machine Control and Guidance tools continue to reduce project risk and attract quality resources with skill sets new to the earthmoving industry. These tools increase production, reduce rework and help with government permitting.

May 1, 2013

By J. M. Houston

"In October 1982, Rio Algom Limited, purchased a tin prospect near East Kemptville, Nova Scotia, from Shell Canada Resources. This purchase led to the development of the first substantial tin mine in North America. This paper deals with the drillingand blasting operations at Rio Algom, in particular the use of emulsion explosives technology.This presentation describes what emulsion explosives and Heavy AN/FO are, and the support system used to deliver these products to the blast site.HistoryThe East Kemptville mine site was discovered by Shell Canada Resources (SCR) in July 1978. SCR started diamond drilling on the tin prospect in March 1979. After 8220 m of BQ drilling, it was estimated a reserve of 56 000 000 tonnes of 0.165% Sn was present.The property, which is located 54 km northeast of Yarmouth, Nova Scotia (Fig. 1), showed, after a feasibility study that, given an ore treatment rate of 9000 tonnes per day, a mine life of 17 years could be expected.GeologyThe tin deposit of the East Kemptville Mine, occurs in granitic rocks at their contact with metasedimentary rocks. The mineralization is in the form of cassiterite with associated sulphides of copper and zinc. The tin occurs in a stockwork of tin bearing Greisen alteration zones.East Kemptville MineThe mine planned an open pit operation with the first five years being mined at a rate of 14 000 tonnes per day, of which 5000 tonnes will be waste and low grade ore. Eventually, the total mining rate will be 21 000 tonnes per day, including 12 000 tonnes of waste and low grade ore. Figure 2 shows the general layout of the mine site.East Kemptville Chooses Emulsion ExplosivesIn December 1984, East Kemptville Mine awarded the Explosives Division of C-I-L Inc. a contract to supply explosives to the borehole. The system chosen gives East Kemptville the on-the-bench choice of regular AN/Fa, or a high density, Heavy AN /Fa product called SuperAN· or a water resistant emulsion explosive called MAGNAFRAC· for holes that cannot be dewatered.Emulsion ExplosivesAn emulsion is an intimate mixture of two liquids that do not dissolve in each other. Emulsions have contributed to our daily lives in such products as insecticides, salad dressings and cosmetics."

Jan 1, 1987

By J. Lee

As the usage of BIM increased in the construction industry, some construction owners started exploring the use of BIM for maintaining their facilities. Construction Operations Building Information Exchange (COBIE), a spreadsheet data format suggested in 2007 to manipulate building information, is considered as one of the solutions that would facilitate the process of transferring information from BIM to applications for facilities management. Several BIM and Computer Aided Facilities Management (CAFM) applications offer functions to export or import the COBIE data. To facilitate the process of generating the COBIE data out of Building Information Model, some add-in applications, such as COBIE Toolkit for Revit, also were developed. However, most of these applications handle a limited amount of COBIE data. Professionals using these add-in applications therefore sometimes end up spending a significant amount of time to add additional data manually to the COBIE data file. To automatically get a data-rich COBIE file, we developed a prototype application that extracts information from Revit, which is one of the BIM authoring tools, stores them in an external database, and then produces the COBIE file using information stored in the database. We applied our application to a pilot project and produced 8 COBIE worksheets automatically, which demonstrated a significant amount of time saving. This paper presents how our prototype application produces 8 COBIE data sets automatically. It also addresses our attempt to handle more COBIE data sets.

Aug 1, 2013

By John G. Henning

The Hoyle Pond underground mine is located in the Porcupine Gold Camp, 18 km east of downtown Timmins. Since the initiation of production in 1985, the operation has produced in excess of 1.9 million ounces of gold at a grade of 15 grams per tonne. Currently, Hoyle Pond ranks 8th in total ounce production for all past and present producing mines in the camp, with the highest head grade of any of the significant past, or present producing mines in Timmins. Cut and fill, shrinkage, longhole and panel mining methods are employed to excavate the narrow gold bearing structures. Using illustrative examples, this paper provides an overview of factors, such as geologic setting, rock mechanics challenges and mine infrastructure, which influence mine design at Hoyle Pond.

Oct 1, 2004

By A. D. Thomas, V. N. Rampton, S. Paradis, C. F. Gleeson

"A shallow till sampling program was completed on a 1 km grid over the St . George Batholith in southern New Brunswick. The ""B"" soil horizon was analyzed for Cu, Pb, Zn, Ag, Co, Mo, U and Sb and the heavy minerals from the ""C"" soil horizon were analyzed for W, Sn and A u. The results delineated four of five recorded W occurrences, three of four recorded Mo occurrences, all recorded Cu occurrences and one recorded Au occurrence. The results indicate that shallow till sampling in conjunction with bedrock and Quaternary mapping can inexpensively define exploration targets in terrain similar to that underlain by the St. George Batholith.A similar program was carried out in eastern Ontario involving the analysis of four separates from the till, the ""8"" soil horizon, the -50 mesh fraction, the -250 mesh and the heavy mineral fraction of the ""C"" soil horizon and humus. Also sampling was carried out near known gold occurrences at closer spacings. Regionally, anomalous results from all sample media clearly defined a large auriferous shear zone and associated splays. Over one known showing all media clearly defined the showing and a secondary zone. On the regional scale the heavy mineral fraction gave the best anomaly definition and contrast, but the -250 mesh fraction was found to be the most cost effective for defining exploration targets. For detailed surveys, humus was found to be cost-effective."

Jan 1, 1986

Overview ?G-9 Discovery Hole 420 drilled May 2005 ?14.16% Zn, 1.76% Cu ?Greenfield discovery built into the G-9 Mine in under 4 years. ?Utilized a unique ?Parallel Track? approach to fast-track mine development. ?Raised over $200million in financing without a Feasibility Study. ?Mine built for $149.7 million, only 20% over PEA. ?Commercial Production declared April 1, 2009. ?G-9 Mine has now completed the first year of commercial production on April 1, 2010. ?Initial cash costs per pound of zinc US$0.39/lb -US$0.45/lb range. ?Mill operating at over1,900 tpd in March 2010, well above design capacity (1,500tpd) only one year after starting commercial production. ?Balance Sheet -$167 million assets, $24 million long-term debt, $22 million cash. ?Restarted Exploration ?excellent initial results. ?Strategically positioning Farallon to grow to a mid-tier mining company.

May 1, 2010

By R. Scheepers

"Abstract -Mineral deposits and prospects of the Pan African Saldanian orogenic belt in the south­ western Cape Province South Africa, are reviewed. Despite the entire absence of operating base or precious metal mines in the area, this study has established at !east four metal associations that offer enticing exploration potential .The poly-phase deformed, low-grade metamorphosed volcano-sedimentary Malmesbury Group constitutes a complex, poorly understood supracrustal sequence that has been loosely subdivided into the Tygerberg, Swartland and Boland tectono-stratigraphic terranes by northwesterly trending fault zones. Syn- and post-tectonic granitoids of the Cape Granite Suite selectively intruded these terranes. Early S-types preferred the Tygerberg terrane whereas the later I-types dominate the remaining areas. Anorogenic A-type granites, however, occur in all three domains. Known metallization is directly or indirectly related to the intrusives, yet syngenetic deposits are conspicuously absent from the supracrustals. Four metal associations have been identified.•,Cassiterite-wolfrarnite (± Au, Cu, Mo, Fe-sultides) in quartz and quartz/aplite veins hosted by tourmalinized and locally greissenized S-type granite. Similar exo-granitic veins occur in proximal metamorphites.•,Juxtaposed disseminated, stockwork, breccia and vein style Cu-Mo-Fe-(Au)-sultide mineralization hosted by matie to intermediate intrusives of high K calc-alkaline, 1-type affinity.•,Cu-Mo-Au-sultides hosted by hydraulic breccia pipes, stocks and veins occurring in anorogenic A-type alkali feldspar granites and amphibole quartz syenites.•,Scheelite with minor Cu-Mo-sulfides and Au-associated with endo- and exo-skarns spatially related to I-type monzogranite, granite and alkali feldspar granite .The first three associations occur along the Yzerfontein-Helderberg-Zone, a 180 km lineament in the Tygerberg terrane, a zone exploited by syn-, late- and post-tectonic intrusives and their related mineralization. The fourth association is typical of the Boland terrane. The spatial and temporal relationships between the various metal associations is interpreted as the result of sequential intrusion of relative early high level S-type, followed by intermediate level I-type and finally anorogenic A-type granitoids during the evolution of a contracting continental margin arc and its inner arc. This plate tectonic setting suggests subduction in an easterly direction underneath the Kalahari craton. The spatial configuration of the various terranes at the present erosional levels is the result of rifting and significant differential vertical displacement following cessation of subduction, a terminal tectonic event possibly synchronous with intrusion of the A-type granitoids.Near surface preserved roof zones and cupolas of both S- and I-type granitoids in the Tygerberg and Boland terranes, respectively, render these areas extremely prospective for Sn, W, Mo and Au mineralization. The presence of intermediate to mafic volcanics, a diversity of calcareous lithotypes and favorable plate tectonic setting of the Malmesbury Group suggest potential for the thus far elusive VMS, MVT and Sedex base metal and minor precious metal deposits."

Jan 1, 1994

By Cardm Jeffrey W.

The decay of 222 Rn yields a series of short-lived decay products which become attached to the surface of a plate or wire exposed in a 222Rn-bearing atmosphere. The alpha-activity of two of the decay products, 218Po and 214Po, can be measured by simple counting techniques. This phenomenon may have direct application to uranium exploration. Laboratory studies have shown that: (a) radon decay products can be collected on a wide variety of materials (including various kinds of metals and plastics); (b) activity increases as a function of the surface area of the 'collector; and (c) the collection of the decay products is enhanced by applying a negative charge. The new technique was used in situ to delineate the anomaly above the South March uranium-copper occurrence. A related technique was developed to measure radium in soil samples. The results of both studies compared favourably with those obtained from conventional methods.

Jan 1, 1979

By Bern Klein, Randy Blaskovich, Reem Roufail

"Morphology is a tool that is rarely used for mineral breakage mechanism evaluation. Ground particles are typically assessed for their size distribution. They are also visually analyzed using image analysis. However, image analysis is not a comprehensive evaluation of the particle surface texture. It evaluates particle’s size parameters such as area, diameter, and perimeter amongst other features. On the other hand, morphology analysis takes the particle assessment to another level of detail. Morphology analysis evaluates particles’ roundness, elongation and angularity that would indicate the degree of roughness of the particle. According to Roufail and Klein (2009), rougher surfaces are generated due to breakage along grain boundaries – intergranular breakage. Mill operation, particularly mill speed, dictates the dynamics in the mill. Stirred mills are known to break the particles via abrasion under standard operation. However, if the dynamics of the grinding media in the mill are changed, the particles could be more exposed to impact and compression loading that would lead to a different mode of breakage.In this paper, the effect of material properties and mill operating conditions on particle morphology will be studied. Hard non-sulfide versus soft sulfide minerals are compared, namely quartz and galena, respectively. Extreme mill speeds are tested covering the range of 1000 to 2000 rpm for a 4-litre Netzsch (ISA) mill. In addition to particle size distribution, micro-analysis is executed in the form of morphological analysis using a tested manual roughness point counting technique.INTRODUCTIONGrinding in general and stirred milling in particular are processes that are used to break particles to liberate metal-bearing minerals for further separation downstream. The energy required to achieve the target particle size versus maximum possible liberation has been studied intensively and it is usually the breaking point for the grinding system chosen in a process flowsheet. Operating conditions are dictated by the energy consumption. Becker et al. (2001) related different forms of energy such as input, specific, volume/mass specific energies to stress intensities and final product fineness. Other research studies focused on energy input in a stirred mill (Zheng, Harris and Somasundaran, 1996)."

Jan 1, 2011

By B. Tanda

A process has been developed at Curtin University whereby glycine is used in an alkaline environment to leach gold, silver and copper from their ores, concentrates, process intermediates and wastes. Copper mineralisation investigated includes various oxides, sulfides and native copper. The leach process utilises an oxidising environment such as oxygen. Glycine is a non-toxic, non-volatile, edible, low cost reagent which is produced in large industrial quantities for use in several industries. Glycine and its copper and precious metals complexes are stable over wide pH, Eh and temperature ranges. Other than losses in leach residues, the glycine is recovered and recycled for leaching. Iron dissolution is insignificant in the pregnant leach solution. Iron in pyrite remains unaffected, whereas iron associated with base metal sulfides (e.g. chalcopyrite and bornite) is converted to a readily filterable iron hydroxide. Efficient separation of copper by solvent extraction and conventional electrowinning has been shown to be feasible for a number of organic extractants, whereas gold and silver glycinates adsorb very well onto carbon allowing CIP/CIL/CIC (carbon-in-column) based processes. The process is ideal for ores containing acid-consuming gangue, concentrates with high arsenic or halide contents and for copper-gold ores with significant sulfide mineralisation. The process eliminates many of the problems associated with the processing of copper-gold-silver ores, such as elemental sulfur formation, silica gels, unwanted metal co-dissolution, and jarosite precipitation. The reagents used and process residues are much safer and environmentally benign than conventional process options. The processing technology can be applied to in-situ, heap and vat, or agitated tank leaching at temperatures ranging from ambient to below 100?C at atmospheric pressure and is currently being commercialised. This paper will focus on copper leaching and recovery and iron rejection from a chalcopyrite flotation concentrate.

Jan 1, 2016

By J. Budac, R. Kofluk, D. Belton, M. Sjogren

A series of tests were performed to determine the flammability limits of mixtures of oxygen, ammonia, steam and nitrogen, over a solution, in a sealed autoclave. The partial pressures of ammonia and oxygen in the vapour space were varied by adjusting the character of the solution and by adjusting the oxygen concentration in the oxidant gas respectively. The data shows that flammable conditions can be minimized by controlling the operating temperature, reducing the ammonia content in the solution, increasing the concentrations of Ni, Cu and Zn in solution and keeping the % oxygen in the gas phase less than 15.5. Observations were also made that suggest that the presence of an aerosol in the vapour space may hinder ignition.

Jan 1, 2004