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By T. Moyo

Ammoniacal solutions are attractive and effective lixiviants for the dissolution of chalcopyrite, allowing for the formation of stable ammine complexes with copper while rejecting iron. Chalcopyrite dissolution in ammoniacal solutions is reviewed from literature, and results from a recently completed study evaluating it through electrochemical and controlled leach studies are discussed. Ammoniacal leaching of copper ores dates back to 1916 in the leaching of low grade copper ores in the Kennecott leaching plant and in the Calumet and Hecla mines, followed by the commercialisation of the Sherrit Gordon process for the ammoniacal leaching of sulphide copper ores in 1948. Since then ammoniacal leaching has received intermittent focus from researchers with the development of the Anaconda’s Arbiter process and the unsuccessful Escondida process. In these leaching processes, the formation of surface deposits has historically been reported to result in the passivation of the chalcopyrite surfaces, whereas oxygen mass transfer in solutions has been the focus of process design improvements. Results of studies on high grade chalcopyrite material is presented in this paper which show that although a surface deposit was formed, it did not result in the passivation of chalcopyrite in ammoniacal solutions, and that while oxygen transfer is critical, it is not the direct oxidant in the reaction. INTRODUCTION Ammonia and its salts have been used in the hydrometallurgical treatment of non-ferrous metals such as copper, cobalt and nickel from oxide ores. Its chemistry allows for the selective dissolution of desired metals, leaving behind gangue including iron. Chalcopyrite is a copper sulphide ore known to be very stable and hence recalcitrant to many hydrometallurgical processing methods. Thus, the dissolution of chalcopyrite continues to be an attractive area of research. The dissolution of chalcopyrite in ammoniacal solutions is possible due to the stabilisation of copper(I) and copper (II) ions by ammonia in alkaline media. Ammonia has become more attractive as a lixiviant during the present socio-economic climate due to its low toxicity, relatively low cost and ease of regeneration by evaporation (Meng & Han, 1996). Ammonia processes are ideal when the gangue minerals are acid consuming e.g. with calcareous or dolomitic gangue (Paynter, 1973).

Jan 1, 2019

By Ashley Tews

In 2005, we automated a forklift-based Hot Metal Carrier to be capable of typical metal transfer operations around a smelter. The project was highly successful and the vehicle has demonstrated hundreds of hours of live autonomous operations to thousands of people from industry and the public. As a result of the exposure and success of the project, we have expanded its focus to demonstrate how various technology components can be utilised to gain benefits in other areas of industrial operations. These include asset tracking, vehicle usage analysis, pedestrian detection and infrastructure profiling. Each of these components was derived from the core autonomous vehicle technology suite and has shown a high potential for improving safety and efficiency of vehicle-related operations, and improved diagnostic processes for measuring deformations of bakes and furnaces. The autonomous vehicle project and its extended technologies are described in this paper.

Aug 1, 2013

By Adriana Ramirez, Bradford C. Wesstrom, Blanca Olave

The Freeport McMoRan El Paso Copper Refinery optimizes electrolyte quality using a number of systems. The facility controls copper, arsenic, antimony and bismuth using electro-winning cells within the Tank House and Nickel Carbonate Plant Liberator Circuit (NCP). The NCP manages sulfuric acid content utilizing recycled electrolyte in the slimes autoclave as well as operation of the Acid Purification Unit, APU. The El Paso Refinery removes common sulfates using metal hydrolysis with sodium carbonate. Finally, a Mechanical Vapor Recompression, (MVR), at the water recovery plant removes sodium sulfate generated by the NCP. This paper will provide a summary of these operations. INTRODUCTION In the mid 1920’s Nichols Copper Company, in Laurel Hill, New York, recognized the need for a modern copper refining facility in the southwest. Because of the many railroad heads, affordable power and abundant labor supply, and the close proximity to regional copper smelters in Mexico, Arizona, and New Mexico, El Paso became the ideal location. In December 1928, ground was broken for the joint venture refinery between the Nichols Copper Company, Phelps Dodge, and the Calumet and Arizona Mining Company. In September 1930, Nichols Copper Company became a part of Phelps Dodge Corporation after a stock exchange. In July 1938, Nichols Division officially became Phelps Dodge Refining Corporation. In March 2007, Freeport McMoRan Copper & Gold acquired Phelps Dodge. Water is a precious commodity in the desert southwest, making conservation of this natural resource an important goal for the El Paso Operations. In the 1980’s, work on the treatment of slimes was improved through the use of pressure leaching of the refinery slimes using an autoclave. Due to the high tellurium content in the leached slimes solution, it was crucial to implement a method for its removal before the solution returns to the tank house electrolyte. A copper telluride cementation operation was installed for tellurium recovery and the ability for the recycle of the leachate and wash water to the refinery electrolyte. In October of 1997, ground was broken for the construction of the water recovery plant using an MVR to reuse process water, reducing water consumption by 25%. In 2002, electrolyte purification was further improved with the installation of an Acid Purification Unit, (APU) (Sheedy, Pajunen, & Wesstrom, 2007). The APU recycles 90% of the acids (both sulfuric and arsenic acids) back to the tank house electrolyte. The solution that passes through the APU is treated with soda ash to precipitate metals out of solution as carbonates and generates a sodium sulfate solution. This sodium sulfate solution is easily processed in the new water recovery plant, where the majority of the water recycles back into the plant as pure condensate. In 2012, the power plant at the refinery upgraded its Reverse Osmosis System to provide RO water to the tankhouse. This insured that the refinery would not have to bleed electrolyte for metals contained in well water such as: calcium, magnesium, iron and sodium chloride.

Jan 1, 2019

"The Australasian Joint Ore Reserves Committee (JORC), which is sponsored by the Australian mining industry and its professional organisations, developed the JORC Code to provide minimum standards for public reporting. JORC was first published in 1989 and later incorporated into the Listing Rules of the Australian and New Zealand Stock Exchanges making compliance mandatory for listing public companies in Australia and New Zealand."

Jan 1, 2003

By T Salman

The construction and use of the B.E.T. (gas adsorption) apparatus is described. Examples are given for the determination of large and small surface areas using nitrogen and krypton. Introduction A NY study of the milling of ores from crushing to grinding, classification, and concentration and finally dewatering of the products involves solid particles which are either in contact with a gas or a liquid phase. The surface area of the solid and its characteristics constitute important parameters in all mineral dressing operations. The success of any particular operation is dependent on the interaction of the surface of the solid particles with the gas or the liquid phase. Particle size and specific surface (surface area per unit weight) continue to be important parameters in the flotation research associated with the adsorption of collector molecules or ions on mineral particles, as in the early years of mineral dressing research (1). In order to understand the mechanism of the flotation process, it is essential that the surface properties of the adsorbent be known.

Jan 1, 1965

By S. E. El-Alfy, John Starkey

"The Iron Ore Company of Canada treats up to 125,000 t/d of iron ore at its Carol Concentrator in Labrador City, NF.A complete water balance study in the concentrator was done to show how to reduce the consumption of fresh water, to improve metallurgy in the magnetic separation (mag) plant, and to help reduce maintenance costs for the reclaim water and tailing pumping systems.The study showed that more than 60% of the water used in the mill was internally recycled dirty water from dewatering cyclone overflows, and that water reduction was closely tied to the effective use of these internal reclaim pumping systems. In addition, new operating parameters were set for the 4 -15,000 USGPM reclaim water pumps which should save over $100,000 per year in maintenance costs.IntroductionThe study described in this paper was set up for the purpose of lowering water usage in the concentrator, and to reduce tailing and process water pumping costs (operating and maintenance). Another benefit was also expected, namely, to improve magnetic separation efficiency through better water and density management of magnetic separator feed streams.The procedures selected to perform this work were: ( 1) to prepare accurate, as built flowsheets of the entire iron recovery process, including fresh and process water systems, (2) to calculate normal material balances in all circuits at full production, (3) to use the computer spreadsheet model so generated, to evaluate specific ways to reduce water consumption and (4) to re-evaluate metallurgical performance and operating parameters in the light of this information.Overall control of the 28 spiral iron recovery lines was found to be excellent because automated start up and shut down of the individual lines had been incorporated in the design from the start. Because production rates can vary due to sales requirements, mine and mill maintenance delays and hardness variance, the mag plant (which treats spiral tailings) must deal with a wide variety of operating conditions. Good water management therefore is a key item in achieving high recovery of the fine free magnetite which is too fine for recovery in the spirals.In order to make the study as accurate as possible, process data for major flows was reviewed by metallurgical staff and then by mill supervisors. The operating picture of the concentrator so generated was judged to be a good estimate of the mill at full production. By changing key inputs, the variance of process water demand and tailing slurry produced for several other operating conditions were studied.The usefulness of this exercise has prompted this present presentation to be made. Older plants by nature have undergone many revisions as operators have worked through ore changes, market changes, labour cost increases and the availability of new equipment, to improve their operation. Sometimes therefore it is necessary to stop and reassess what is happening in a plant in order to continue the never ending work of process optimization. The techniques used here were ideally suited to the gravity/magnetic concentration flowsheets used, but there is no reason why similar studies could not be done in other process plants.The authors of this paper hope that this experience at IOC will be helpful to others who face similar challenges in the pursuit of excellence in their processing plants."

Jan 1, 1995

By G. Vibert Douglas

Introduction A preliminary paper dealing with the subject of ore-shoots was presented to this Society at its Annual Meeting last year (1). The present paper records the attempts which have been made during the interval to further this study. In reporting this work, I wish to state that I do not consider the investigation complete; many more experiments will have to be carried out, and more field data will have to be recorded, before the geologist can say with confidence an ore-shoot should start at this point and pitch in that direction. The aim of these experiments is to find some criteria which will serve the mining engineer and mining geologist concerned with ore-shoots in hydrothermal veins.

Jan 1, 1935

By W. S. (Steve) Vaughan

The Origins of Joint Ventures in Canada?s Mining Industry ? Among the most important financing structures used in our mineral industry today ? Virtually unheard of in the Canadian industry prior to the 1970s ? Borrowed from the U.S. oil and gas sector where it came into prominence in the late 1930s ? The Securities Acts of 1933 and 1934 in effect killed the sale of (equity) shares for financing oil and gas wells and start up mining companies

May 1, 2013

By R. L. Bruening, L. Navarro, R. M. Izatt, N. E. Izatt, S. R. Izatt

Green chemistry principles will be discussed, and examples will be given of the use of Molecular Recognition Technology (MRT) to selectively separate valuable metals such as rhenium and palladium from various copper refinery feed streams. Recovery of these metals has numerous advantages including (i) conservation of valuable resources, (ii) prevention of environmental damage, and (iii) elimination of capital and operating expenses due to re-processing or disposal of metal-bearing streams. INTRODUCTION Refining of copper ores has a long and successful story. The history of copper, one of the first metals mined in human history, illustrates the global challenges faced as a result of increased demand for major metals and for by-product specialty metals found with them in trace amounts (Izatt et al., 2014). Copper has valuable properties, which have sustained its use over the centuries. It is an ideal material for creation of novel materials. Some desirable properties of copper that have proved valuable in our high-technology society include suitability for alloying with many other metals; ease of joining by soldering and brazing; good combination of mechanical qualities; high resistance to corrosion; suitability for many artistic purposes; and, of great importance in the modern era, efficient and economic use as a conductor of electricity. Copper mining in the U.S.A. began in the late nineteenth century in Montana (Izatt et al., 2014). The estimated total amount of copper mined globally before 1800 is about 5 million tons, four times less than is mined in a single year today (Flanagan, 2018). Production of copper in the U.S.A. has remained fairly constant at about 1,300,000 to 1,400,000 metric tons per annum from 2013 to 2017. Specialty metals such as bismuth, rhenium, molybdenum, and others that have become essential in our 21st century technology, and precious metals such as silver, gold, and the platinum group metals (PGMs) are concentrated by geochemical processes in trace amounts in copper ores. These specialty and precious metals were discarded into tailings in early mining operations, since limited extractive technologies existed and uses for most of them were limited. Thus, economic benefits for recovering them were limited, primarily, to silver and gold. Today, copper processing is the main, and often the only, commercial source for certain of these elements (Izatt et al., 2014). For example, molybdenite (MoS2) is the predominant ore mineral of molybdenum mining (Pohl, 2011). Cu-Mo-Au porphyry ore deposits supply ~75% of the world’s copper, 50% of the molybdenum, nearly all of the rhenium, and 20% of the gold. Typical ore grades are 0.5–1.5% copper, 0.01–0.04% molybdenum, and <1.5 g/ton gold. Molybdenite is the primary source for rhenium, among the rarest of metals, which is an essential component of super alloys, such as turbine blades in the aerospace industry (Pohl, 2011). Most rhenium is obtained as a by-product of molybdenite from copper mines in Chile. The case of rhenium raises an important issue. Continued availability of rhenium, selectively concentrated in copper ores, depends on continued mining and processing of copper. Since the mining company’s main interest is typically in copper production, continued recovery of rhenium and other specialty elements present in the ore body is at risk. Dependence of specialty metal supply on continued mining of major metals exists in several additional cases including indium, gallium, selenium, tellurium, germanium and bismuth (Pohl, 2011). PGMs, on the other hand, are typically mined for their own value, which far exceeds that of associated base metals. However, copper ores often contain marketable amounts of platinum and palladium, making their separation of interest, if this can be done economically.

Jan 1, 2019

By Kai Zhang, Aijun Huang, Jeremy H. Rao, Xinhua Wu, Paul Rometsch

"As one of the most typical additive manufacturing (AM) technologies, selective laser melting (SLM) removes many of the shape restrictions that limit materials design, thereby allowing computationally optimised and high performance structures to be directly produced and tested. Due to the high reflectivity and lower absorptivity of Al alloy A357 powder during high temperature laser melting, one of the issues SLM might bring is the surface roughness and defects present on the parts. In this regard, this study investigates the surface roughness – fatigue property relationship for a heat-treated aluminium alloy A357 after SLM. Via the adjustment of SLM parameters, an ultrafine microstructure can be obtained due to the fast solidification rate. Therefore, comparable or even better mechanical properties can be achieved with respect to traditional A357 casting counterparts. Meanwhile, the surface roughness conditions of the SLMed Al alloy are also influenced by various processing parameters, raw powder properties, and sample building methods. For selective laser melted Al alloy A357 specimens, a dense part with a smoother surface would be expected to correspond with a good fatigue performance.INTRODUCTION Additive Manufacturing (AM), also known as 3D printing, is a process in which a complex part is fabricated layer by layer from a digital design package (Martin et al., 2017). AM has the potential to conserve raw materials, reduce the energy consumption, part cost, and fabrication time. Furthermore, as a typical additive manufacturing (AM) process, selective laser melting (SLM) was originally developed from selective laser sintering (SLS) based on higher quality lasers (Rao, Zhang, Fang, Chen, Wu, & Davies, 2017b). Different from conventional casting consuming valuable time and energy, SLM is now used as a cost effective method for the manufacturing of metals, such as Al-Si alloys, to produce almost full density parts using fine metallic powder and high power laser beam (Tang & Pistorius, 2017)."

Jan 1, 2018

By Z. Zhang

Aluminum boron carbide particulate reinforced composites have found new applications in nuclear industry due to their special capability to capture neutrons, Recently, Alcan successfully developed a liquid metal mixing process to fabricate Al¬B4C metal matrix composite instead of powder metallurgical technology. In the process, titanium is added into the composites to control interactions between boron carbide particulates and aluminum matrix, To understand the effects of titanium on the composites, the solidification microstructure of Al-16%B4C without or with titanium was examined by optical and electron microscopes. The results show that titanium can improve the uniformity of the particulate distribution within aluminum matrix if the titanium content in the composites is more than 0,5%, Furthermore, it is found that the layer with rich titanium on the surface of the particulates can limit the formation of AlB2 type compounds, which may greatly deteriorate the fluidity of the composites, In addition, it is also found that the amount of the reaction products in the composites increases with the increase of holding time. However, the rate of the increase is mitigated by the increase of the content of titanium in the composites. Besides, a procedure was proposed and implemented for the evaluation of uniformity of particulate distribution within aluminum matrix.

Jan 1, 2005

By G. F. Warning

"THE H. B. Mine is situated on the north side of Sheep Creek valley, about six miles southeast of Salmo, B.C. It is the most northerly producer along a belt containing a number of zinc-lead deposits, including the Jersey mine of Canadian Exploration Limited, 3 miles to the south, and the Reeves MacDonald mine, 12 miles to the southwest. The important zinc-lead producing area around Metaline Falls, Washington, lies 23 miles to the south. Two prospectors, Horton and Benson, located and staked the oxidized outcrops in 1.907. The property was named the H.B. after the two discoverers. Exploration by a number of operators failed to locate any sulphide orebodies until 1946, when Cominco began a geological study followed by surface drilling which was successful in locating extensive sulphide mineralization. A program of underground exploration revealed sufficient ore to war-rant mill construction. A 1 ,000-ton mill was completed by 1953, but due to low metal prices production was deferred until May, 1955. To September 1, 1959, 1,900,000 tons of zinc-lead ore have been milled; present milling rate is about 1,250 tons per day. Concentrates are trucked to the Trail Smelter, a distance of 35 miles."

Jan 1, 1960

By Z. S. Abisheva

The Zhezkazgan copper sulfide ore deposit in Kazakhstan contains both rhenium and the rare osmium isotope "osmium-187" (187Os) in the high isotopic purity of 99.4 ± 0.2%. This isotope is believed to have originated as a result of the disintegration of one of the rhenium isotopes, according to the reaction: 187Re75 ?> 1870576 + B- + v~ (where B is a 13-particle, v~ is a 3-disintegration antineutrino). The distribution of osmium and rhenium in metallurgical byproducts produced during the recovery of copper from these ores has been studied and process flowsheets for the processing of rhenium and osmium-containing byproducts have been developed.

Jan 1, 2007

By N. Nemeth

A brief summary of available filtration research is given. Its usefulness and shortcomings to practical application are examined and suggestions for new avenues of research outlined.

Jan 1, 1967

By F. Charette

Instrumentation has been developed that can monitor the strain applied to a D-Bolt up to 7.5% elongation. The technology far exceeds the limit for foil resistance strain gauges. In the laboratory the instrumentation has provided insight into the fundamental behaviour of the D-Bolt following yield. Currently the instrumentation is undergoing field trials at a number of Canadian Mines. Discussion on field results is provided with regards to significance, reliability and temperature effects.

Aug 1, 2013

By L. G. Smith, C. A. Shook, W. H. W. Husband, W. Schriek

"The flow of slurries in pipelines is governed by many variables, and the study of the influence of each of these variables is difficult, if not impossible, in some cases. Many correlations are available which fit data within a given range. However, no one method is yet available to design a slurry pipeline for all desired conditions without at least some physical measurements on the slurry itself. For this reason, the slurry pipeline facilities at the Saskatchewan Research Council have been developed during the past 12 years and it is hoped that the development will continue until the process is thoroughly understood and test facilities are no longer necessary. This paper outlines methods currently used and under development at the Saskatchewan Research Council for measurement, control and study of the variables governing the flow of slurries."

Jan 1, 1973

By R. S. Douglas

Introduction The mine at Copper Mountain of the Granby Consolidated Mining, Smelting and Power Company was one of the pioneers in the use of blast-hole diamond drilling for ore breakage. This method of mining has now been brought to a high degree of perfection. The system in use has?been described in a previously published paper which has become an important part of the literature o the blast-hole drilling method. At the time of the establishment of the system at Copper Mountain, standardized loading and drilling procedures were set up. These procedures were based partly on the results of experiment and partly upon the judgment of men experienced in breaking rock in the mine. The success of the method has been proof of their adequacy. With the progress of scoping in the mine, the diamond drill method of breaking was applied to other ore blocks where different conditions obtained. It was found necessary to make adjustments in the standard procedures to get the best results under the new conditions. The following paper attempts to express, in terms of mathematics, the relations of the variable factors. Until recently, estimations of drilling required were based upon the tonnage to be broken and the proposed rate of explosive loading. A revised method of estimating is outlined below which is direct and which involves no unrelated variable factors.

Jan 1, 1947

By A. M. Bell

"Hallnor mine is in the township of Whitney, Porcupine district. To date, its production of gold has been second largest in the east Porcupine field. Ore was discovered in the property in 1936 by diamond drilling in overburdened country. This drilling was undertaken by Noranda Mines following the discovery of ore in conglomerate at Pamour 1 mile to the east.Milling commenced at the Hallnor in June 1938, and to the end of 1945 432,000 oz. gold had been produced from 889,000 tons of ore, giving an average recovery of 0.49 oz. a ton.The West mine of Pamour, the Broulan orebody, and the veins on the Hallnor and Bonetal are all parts of a mile long vein system that has been separated into three sections by cross faulting. In consequence, they could well have been described in one paper. In treating them individually the viewpoint obtained from each may lead to conflicting opinions, and any conclusions advanced in this paper on the general structure should be modified by the conclusions advanced in papers on the neighbouring properties.GENERAL GEOLOGYRock FormationsThe Hallnor orebodies occur within 400 feet of the contact between lavas and sediments, and may lie in either lavas or sediments. The lavas near the ore consist of flows of pillowed andesite and one flow of more acid and less sheared and chloritized lava locally named trachyte. These flows strike east-west and dip steeply. At the surface on the east side of the property the volcanics have been intensely altered to a massive carbonate rock having a north-south thickness in excess of 1,000 feet . This carbonate body extends west across the property with a plunge of 45° (Fig. 1)."

Jan 1, 1954

By J. De Geoffroy, T. K. Wignall

The paper describes a statistical method based on regression and classification analysis which is designed to assist exploration management in the selection of prospecting areas and drilling targets in regional programs. The classification is based on three criteria which are formulated from sets of relevant geological, geophysical and geochemical factors: (a) regression estimates of expected ore values, (b) Bayesian probabilities of success and (c) expected utility payoffs. The advantages of the method are: (a) rational and unbiased ratings for areas or targets in a manner consistent with management's goals; (b) calculation of probabilities of success and confidence intervals for the ratings, and (c) rapid and accurate handling of a large amount of data by computer programs.

Jan 1, 1970

By S. H. Seyedein

A mathematical model was developed to study fluid flow and solidification in a single-roll casting system. Fluid flow coupled with energy equations were solved numerically using a finite volume method. A body-fitted coordinate transformation technique was adopted to handle the irregularly shaped domain. In order to couple the continuity and momentum equations, a SIMPLEC algorithm was used. A fixed-grid enthalpy method was considered to model the solidification in the system. The turbulence effect on flow field was modeled using a low-Re k-e model The model developed in this work was further run under various conditions to optimize the operating parameters of the process.

Jan 1, 2004