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By G. Guzman, L. Sevilla, M. Botz

"Newmont Mining Corporation operates the Yanacocha mine in Perú and the gold milling section of the property includes a Sulfidization-Acidification-Recycle-Thickening (SART) plant to remove copper from pregnant leach solution. Since its commissioning in 2008, the plant has been intermittently operated as needed to remove copper upstream of a carbon adsorption circuit. However, starting in 2015 Newmont expects the plant to operate on a more continuous basis in response to higher copper ores that will be processed in the gold mill. In anticipation of this, Newmont conducted a campaign in May 2014 with stockpiled high-copper ore to evaluate performance of the SART plant with elevated levels of copper in feed solution. Results from the campaign demonstrated the SART plant is capable of efficiently treating high-copper leach solution. During the campaign, leach solution copper levels ranged from about 100 to 700 mg/L, and copper removals ranging from about 56% to +99% were achieved. The median copper removal efficiency observed during the campaign was about 94%. The primary plant modification determined necessary following the campaign was the need to improve consistency with sulfide dosing. INTRODUCTION Copper removal from cyanide leach solution can be affected through the addition of sulfide at acidic pH to precipitate copper sulfide as a solid. There has been renewed interest in the process in the past several years due to the increasingly common issue of high copper levels in cyanide leach solutions. The term Sulfidization- Acidification-Recycle-Thickening (SART) is used as an acronym for the process according to the primary unit operations utilized. At a pH of approximately 4.0 to 5.0, the addition of soluble sulfide to a copper-bearing leach solution will result in the precipitation of copper sulfide (Cu2S) solid. The overall acidification and sulfidization reaction is (assuming the use of sulfuric acid for pH adjustment): 2Cu(CN)3-2 + 3H2SO4 + S-2 ? Cu2S(s) + 6HCN(aq) + 3SO4-2 The above reaction is written relative to the copper-cyanide complex 2Cu(CN)3-2, though analogous reactions also take place with the other common copper-cyanide complexes Cu(CN)2- and Cu(CN)4-3. Sulfide in the above reaction (S-2) is normally supplied as sodium hydrosulfide (NaHS) purchased in solid or concentrated liquid form. Two characteristics of this reaction that are beneficial to a leaching operation are: 1. Copper is removed from solution as Cu2S (synthetic chalcocite) solid, which can then be sold to a smelter for its copper value. 2. Cyanide that is complexed with copper in the leach solution is released as free cyanide, thereby regenerating cyanide that can be recycled to the leaching operation for continued use."

Jan 1, 2015

By S. E. Malouf, R. Hinse

"The Mineral possibilities of the Chibougamau area were first recognized by Richardson in 1870 and Low in 1885, both of the Geological Survey of Canada. The first record of interest by the Quebec Bureau of Mines is in 1904, when J. Obalski reported on the discovery of copper and asbestos by Peter McKenzie in the previous year. Reports of 1906 and 1907 covered the McKenzie Gold Mine find and other deposits. In 1908 Prof. Dulieux described the quartz vein on Merrill Island and the mineralized zone on the near-by mainland. In 1910 the Chibougamau Railway Commission, though commenting favourably on the possibilities of the area, concluded that a railway was not then warranted.In spite of this, prospecting in the district continued. The main Campbell Chibougamau deposit, the Blake showing on Merrill Island in Dore Lake, was found in 1920, and other discoveries were made soon after. Between 1927 the work of Mawdsley, Retty, and Norman tor the Geological Survey and the Quebec Bureau of Mines stimulated further interest. In 1934 Consolidated Chibougamau Goldfields Ltd., a subsidiary of Consolidated Mining and Smelting Co. of Canada Ltd., acquired the Merrill Island and Cedar Bay holdings of Chibougamau Prospectors Ltd. They embarked on an aggressive campaign, directed essentially at the gold quartz veins at Cedar Bay. Exploration there included a 522-foot shaft, 4,732 feet of drifts and crosscuts, and about 34,000 feet of surface and underground diamond drilling. Thirteen holes were also drilled on the replacement sulphide lens at Merrill Island. Operations were suspended in 1936, as the occurrence was too low grade for development at the existing metal prices and under difficult operating conditions.The completion of the Quebec Bureau of Mines highway from St. Felicien to Chibougamau in 1950 was followed by a project of detailed geological mapping by the Bureau. It also encouraged Campbell Chibou-gamau Mines to acquire the assets of Consolidated Chibougamau Gold-fields and commence a program of surface exploration. Between August 1950 and April 1951, 41,183 feet of diamond drilling was done on the Cedar Bay and Merrill Island holdings. The Blake showing off the west shore of Merrill Island developed at depth into a major orebody. A lease was obtained on adjacent ground from Merrill Island Corporation, and underground work commenced in November 1951. Development at Merrill Island to June 1st, 1955, included a four-compartment shaft to 1,225 feet, with 8 levels at 150-foot intervals, 5,317 feet of raises, 16,709 feet of drifts and crosscuts, 52,514 feet of surface and 96,593 feet of underground diamond drilling."

Jan 1, 1949

By George E. Peacock

Campbell Red Lake Mine is situated at Balmertown, in the Red Lake District of Northwestern Ontario, Canada. This area is some 120 miles north of the Trans Canada Highway and is some 160 miles Northeast of Winnipeg, Manitoba. The majority of our 300 employees live in Balmertown, which is a community of some 1,200 people, situated adjacent to the mine proper. The mine is serviced by a single shaft 4,300 feet deep. There are 27 levels at 150 ft. intervals. Stoping is being carried out down to the 20th level with only preliminary development having been done on the bottom 6 levels. The majority of our mill feed of 825 tons per calendar day comes from above the 10th level. Gold occurs as specks and streaks in bluish-grey to white quartz carbonate veins. It is extremely fine grained and most is invisible to the unaided eye. In addition to Gold the veins carry varying amounts of sulphides such as, Arsenopyrite, Stibnite, Pyrite, Pyrrhotite and Sphalerite. A minor amount of silver occurs as an impurity in the gold. Arsenopyrite is a marker for the gold ore at Campbell. The average grade of the mill feed is 0.7 oz. of gold per ton. The ore is dumped into an underground ore pass that feeds to a jaw crusher on the 20th level that reduces the rock to a maximum size of 4". This material is hoisted by skips to an ore bin in the head frame.

Jan 1, 1975

By W. Melnyk, L Pokhilenko, J. A. McDonald, A. Hall

The Camsell Lake property comprises 270 000 acres located about 240 kilometres northeast of Yellowknife in the Northwest Territories. Kimberlite has been located in two areas of the property:

Jan 1, 2001

By B Maybee

In underground mine planning, many potentially value-eroding decisions are made due to a lack of time and proper evaluation practices. The information required for mine planning decisions goes beyond external sources of uncertainty that are recognised by typical evaluation techniques used in the mining industry, to include technical factors (eg mine development layout) and the ability of a mineral extraction project to achieve its anticipated production levels. Due to the individual characteristics that define underground mining projects, each will exhibit a different risk profile, and thus advanced optimisation and evaluation techniques are required to capture this information.As underground mine planning tools become more sophisticated, mine planners have the capacity to investigate numerous mine sequencing options to identify the best strategy for a given project, creating higher value for shareholders. This paper describes a risk-based evaluation methodology (RbEM) that accounts for financial and technical risk in the evaluation of underground mining projects. While the use of the RbEM has been described in previous works, no benchmarking of the benefits that can be realised from a change in those decisions that are made early in the process has been undertaken. To show the benefits that can be achieved from using the RbEM, this paper updates a case study to which the RbEM was applied, and takes a retrospective look at whether additional value would have been gained by following the strategic recommendation of the RbEM versus a typical optimisation exercise that aims to maximise the net present value.CITATION:Maybee, B, 2012. Can a risk-based evaluation provide a more valuable mine design?, in Proceedings Project Evaluation 2012 , pp 53-58 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By R Valenta, J Owen, D Kemp, E Lebre, G Corder, J Thomas

Numerous recent analyses have shown that future demand for a broad range of critical commodities is unlikely to be met by new discoveries and recycling alone. The only practical alternative source to address this shortfall comes from orebodies which are currently either uneconomic or inaccessible. A common assumption is that a simple rise in commodity price will render these deposits economic. The mining industry has a long history of innovation allowing economic production from increasingly low grade and technically challenging orebodies. Industry “roadmaps” have been produced on a regular basis, with the aim of identifying future innovations which will allow this progression to continue. At the same time, there have been relatively few systematic analyses of the actual range of challenges facing undeveloped orebodies. The aim of this study is to analyse the mix of challenges faced by a group of undeveloped orebodies in order to better understand the relative importance and necessity of innovations applicable to the deposits, with the ultimate aim of determining the relative value and impact of possible innovations to the economic viability of those deposits. CITATION: Valenta, R, Lebre, E, Kemp, D, Owen, J, Corder, G and Thomas, J, 2018. Can a simple price-rise unlock complex copper orebodies?, in Proceedings Complex Orebodies Conference 2018, pp 71–72 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By Irsan Chandra

It is generally recognized that the gold thiosulfate leaching system requires the presence of copper and ammonia in order for acceptable leaching kinetics to be observed. However, the presence of copper and ammonia complicate the chemistry of the system as thiosulfate is rapidly oxidized by oxygen under these conditions. In addition, the environmental impact of ammonia would need to be considered before the adoption of this system. This paper describes fundamental studies into the thiosulfate oxygen system. The two reagents for this system are thiosulfate and oxygen, and leaching is carried out at pH < 7. It will be shown using electrochemical techniques that both the reduction of oxygen and the oxidation of gold-to-gold thiosulfate are hindered. Thus, if leaching is to work under these conditions, then both half reactions need to be improved. The use of additives, such as thiourea and lead have been shown to dramatically improve the oxidation of gold and the reduction of oxygen respectively. The leaching of gold in the presence of such additives is discussed.

Jan 1, 2003

By Dever Ashmead

FROM time to time metal-mine engineers have inquired why anthracite mines and their preparators are rarely operated on the two or three-shift basis. The subject may be approached as affecting: labor, development, the underground workers, the preparator, the outside workers, capital, the supply account, power consumption, the storage of coal over various shifts, railroad car supply, and the market. LABOR From the start, the adoption of a plan of three full-shift operations in a day would cause difficulty with the colliery employees, for they have never worked on that plan and would show their resentment by suspending work. Even if they could be induced to work according to this schedule they would not be as efficient, for they would be working more or less unwillingly at hours at which they are accustomed to rest. Operation on a three-shift basis would necessitate triple manning of each working place, and dissensions would arise between the men, for each shift would claim that the preceding shift had taken undue advantage and had not left as favorable conditions as it had found. To obviate these disputes it might be necessary to let out the work to a contractor, who would hire his helpers to mine out the chamber, or breast. The state mining law requires that a miner be put in charge of each working place. To conform with this provision he would have, to hire three helpers and two miners to mine the breast. The labor unions have been trying to abolish the subcontractor in mine work and any method of working that would cause his return, however innocent in purpose, would result in labor disturbances.

Jan 2, 1922

The University of New South Wales (UNSW Australia) has been a world leader in the development of innovative virtual reality technologies over the last 15 years. AVIE (Advanced Visualisation and Interactive Environment) was developed by iCinema as a collaborative venture between UNSW?s Faculties of Engineering and the College of Fine Arts. This is the world?s first 360°-surround, virtual reality (VR) stereo projection theatre system. The School of Mining Engineering at UNSW Australia has developed 18 different virtual reality modules aimed at mine safety training and mining engineering education. These modules are being regularly used in both the mining industry and the university. The School of Mining Engineering is continuously involved in the development of different modules. Research is also currently being conducted on the implementation of other technologies into this environment. Artificial intelligence (AI) and fuzzy logic are tools that the authors would like to consider implementing in future module development. This paper will review current research in both these areas and consider options for applying these technologies.

Jan 1, 2014

By H von Blottnitz, A C. Keith

The influence of the life of a mine extends beyond its immediate vicinity both in geographic and temporal terms. Decisions around mine approvals are generally made based on economics, for the mine owner and immediate environmental and social impacts by governments and communities. The value from life-of-mine planning can also be viewed in a holistic frame across the entire value chain from mine to product user. This research examines the Carmichael Coal Mine in light of the holistic benefits and impacts along its value chain from the mine to relieving the lot of energy poor in India.CITATION:Keith, A C and von Blottnitz, H, 2016. Can Australian coal alleviate energy poverty in India – a case study, in Proceedings Life-of-Mine 2016 Conference , pp 52–56 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By R T. A MacGillivray, S B. Curtis

Bacteriophage (phage) are viruses that infect bacteria. Protein coatings on the surface of the phage particle can be genetically engineered so that they bind to inorganic molecules. The filamentous phage particle is about 930 nanometres in length and 6.5 nanometres in diameter and consists of a single-stranded molecule of DNA surrounded by five different coat protein molecules denoted P3, P6, P7, P8 and P9. Peptide sequences in the P3 coat protein that bind to sphalerite and chalcopyrite have been identified. The binding is selective; phage with specific P3 peptide sequences bind to minerals but do not bind to silica or to pyrite. Two peptide sequences in the P8 coat protein that bind selectively to chalcopyrite and pyrite have also been identified. The amino acids in the P8 binding sequences are hydrophilic and thus a coating of a mineral particle with phage having these peptide sequences may render the particle hydrophilic. Experiments are underway to confirm this. Phage are relatively easy to grow and are not living organisms requiring an energy source to maintain life. Phage can also tolerate a range of pH and temperatures. Given this, and the ability to indentify phage coat proteins that bind selectively to a variety of inorganic molecules, phage have the potential to be useful tools in mineral processing and waste treatment.

Jan 1, 2008

By Grainne A. Matthews

Jan 1, 2009

By Al Holmes

"In a recent survey of Canadian work values, 89% of the men surveyed and 97% of the women surveyed described the work in a mine as ""not at all auraetive"", Work in a mine, in fact, was rated by both sexes as the least attractive of all of the types of work surveyed. Confronted with this prevailing attitude, Canada&apos;s mining industry starts out with two strikes against it in its bid to attract and hold on to its fair share of available work force.Behavioural scientists have, for decades, been seeking answers to the questions:• ""Why do people work?""• ""Why do people choose a particular occupation?""• ""Why do people choose a particular organization?""• ""Why do people leave one organization for another?""• ""Why do some people stay in an organization?""• ""Why do some people work harder than others?""Their answers to these questions, although tentative and often contradictory, are being used by more and more organizations to solve people problems. Few industries can afford to ignore them, least of all, perhaps, the mining industry.Consider the following developments:I. General Motors and the United Auto Workers turn around the car assembly plant in Tarrytown, New York in seven years from the plant with the poorest labour relations and production record to one of the best under a program referred to as ""improving the quality of work life.""2. Shell Canada and the Oil, Chemical and Atomic Workers have designed a new petro-chemical processing plant in Sarnia using a set of principles that seek to optimize both the social and the technical system."

Jan 1, 1980

By G Simpson, S Dressler, A E. Levett

Tailings storage facilities often represent a mining operation’s most significant liability, posing serious environmental, social and safety risks. Almost all mining operations dispose of wet tailings (Valenta et al, 2023), which represents a risk of failure due to the potential for a rapid strength reduction of the unconsolidated materials leading to static liquefaction and subsequent dam wall failure. As a waste stream, tailings disposal, decommissioning and relinquishment aim to be inexpensive processes, ruling out many highly engineered solutions. Advantageously, tailings consolidation does not need to be immediate, opening the door for relatively passive, inexpensive consolidation methods that aim to gradually increase the strength of tailings over extended periods (ie years). In this paper, we present the prospect of novel in situ tailings stabilisation, learning from studies that have investigated the most erosion-resistant landforms on Earth.

Aug 2, 2023

By K. Nielsen, J. Kristiansen

A series of laboratory blasting and grinding tests on three types of hard and competent rock (coarse-grained monzonite, fine-grained granite and very fine-grained gabbro) showed that a higher level of applied explosive energy enhanced grindability and produced a larger amount of fine (-0.106 mm) material. This confirmed reported industrial experience and the results of previous investigations. However, the results did not provide any information on the quantitative relationship between the energy applied in primary blasting and that required in subsequent comminution. Only about 1% of energy consumed in conventional grinding is used to create new surfaces, while power efficencies in cone crushers have been estimated at 70-80%. In blasting, up to 20% of explosive energy may be transmitted to the surrounding rock as elastic strain energy, leading to both primary rock breakage and the generation of microcracks

Dec 1, 1995

By R. C. D. Phillis

The management of critical resource inventories is an important productivity lever and a significant risk factor?risk in the sense that poor resource availability lends itself to disempowerment of workers, unsafe work practices, wasted spending (high unit costs),and poor quality of work (including mining waste/rework). Most underground platinum mines experience lost blasts that directly lead to reduced productivity. In most surveyed shafts, 30% of lost blasts can be attributed to shortages of critical material and/or equipment. The problem is prevalent despite the existence of conventional transitory surface and underground stores. This paper discusses the introduction of buffer stores as a complementary materials storage system in order to improve health and safety in mines as well as reduce lost blasts. Both quantitative and qualitative results have shown that buffer stores result in dramatic improvements in productivity and are readily acceptable by stakeholders. Keywords Buffer stores, lost blast.

Jan 1, 2011

By I. T. Oramah

Despite the abundance of solid mineral deposits, Nigeria only earns about 0.5-1% of its current Gross Domestic Product (GDP) from the solid minerals sector. This is as a result of the dominance of the oil and gas industry, which has negatively affected the competitiveness of other sectors of Nigeria’s economy. The dominance of this industry has resulted in unemployment, poverty, hunger, domestic price inflation, corruption, unstable government, and higher exchange rates. These impacts are typical for economies suffering from the effects of "Dutch Disease" and the "Resource Curse". Community-based small-scale mining offers hope as an economic activity that can create wealth, employment, reduce hunger and poverty, and provide basic amenities for rural communities with solid minerals endowment. This study presents preliminary results of ongoing research into the prospects of using community-based small-scale mining in a developing country like Nigeria to move towards rural sustainable development.

Jan 1, 2011

By Stephen G. Mlot

Technical Study Work ?Technical study work enables informed decisions: -Obtain a higher price for a quality asset -Minimize expenditure on a project that won?t provide adequate returns -Optimize expenditure on a project to capitalize on the potential return

May 1, 2013

By V. F. Hollister

Computer programs developed as part of the PROSPECTOR project at SRI International can indicate where the highest grade hypogene copper occurs in porphyry copper prospects. The programs are useful in selecting drilling targets in untested porphyry deposits. Because of mineralogic, structural and lithologic variations in porphyry-type deposits, three distinct computer programs have been constructed; however, this paper considers only the stockwork type in homogeneous rock (similar to the Lowell and Guilbert model). The programs represent models in the form of inference networks that utilize the mineralogic, alteration, lithologic, structural, geochemical and geophysical data normally collected prior to a drilling decision. One example of an application of the PROSPECTOR program for a stockwork-homogeneous porphyry is given: Island Cooper in British Columbia. Computations based on the surface geologic, geochemical and geophysical data for Island Copper clearly disclose the best hypogene grade of the deposit. Other deposits were tested in the programs as well, and in each case PROSPECTOR programs indicate the region with the highest hypogene grade.

Jan 1, 1983

By P W. Cleary, M D. Sinnott

Cross-belt cutters are commonly used for sampling coal. They are generally cheaper than falling-stream cutters, particularly when a cutter must be retrofitted. The major mechanisms thought most likely to lead to sample bias are being investigated by discrete element modelling (DEM) in a project funded through the Australian Coal Association Research Program. This paper describes a benchmark run and the current direction of research.

Jan 1, 2008