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By V. S. Melamud, A. G. Bulaev

"Sulfide ore processing is characterized by significant losses of metals, for example, with flotation tailings. Therefore, flotation tailings can present an important source of metals. The treatment of flotation tailings is a technological issue due to low content of valuable metals (e.g. copper and zinc) and high iron content. The goal of the present work was to investigate extraction of base metals and gold from old flotation tailings containing 17% iron, 0.26% copper, 0.22% zinc, and 0.7 g/t gold. Chemical leaching in columns with 0.5 to 10% sulfuric acid solutions and bioleaching in air-lift percolators were used for the extraction of base metals. 1% H2SO4 provided high extraction of base metals and best selectivity. Recovery of copper and zinc reached 35% and 40%. Increasing H2SO4 concentration did not lead to significant increase in base metals extraction, but led to increased iron concentration in the pregnant solutions. The 1% H2SO4 leaching solid residues were used for further experiments. Acid leaching and bioleaching did not result in significant increase in base metals recovery. Leaching of the residue with 10% H2SO4 provided extraction of 4% copper and 20% zinc, and bioleaching for 100 days provided extraction of 16% copper and 12% zinc. The recovery of gold by cyanidation from the flotation tailings, the 1% H2SO4 leaching solid residue and residue of two-step acid leaching were 50, 49, and 65%, respectively. The results suggest that acid leaching can be effective approach for treatment of old flotation tailings.INTRODUCTIONAbout 80% of base metals (copper, nickel, zinc) are produced through pyrometallurgical treatment of sulfide ores. Mining and metallurgical treatments of sulfide ores are presently characterized by significant losses of non-ferrous and precious metals into the various wastes. For example, flotation of sulfidic ores yields formation sulfide flotation tailings. These wastes pose a problem not just because of their sheer volume, but some of them may affect local ecosystems. Nowadays, mining and metallurgical wastes can be considered as technogenical source of base metals."

Jan 1, 2016

By Tong Guan, Guangqin Fu, Lihong Deng, Yuanlin Chen, Xiaotong Zhou

"In natural world, some kinds of scheelite minerals are rich in molybdenum. Molybdenum exists in the crystal lattice of scheelite in the form of isomorphism, and the content of MoO3 varies from 2% to 10%. As a result, the flotability of seyrigite (scheelite with molybdenum) turns to be weaker. One seyrigite mine, which has been built for 3 years,still could not produce qualified seyrigite concentrate due to the weak flotability of seyrigite (Mo-bearing scheelite) in raw ore. In our experimental research, through adopting new seyrigite collector TA-3 and advanced mineral processing technology, the seyrigite concentrate with a grade of 65.62% WO3 at a recovery of 87.47% was obtained for the raw ore containing 0.19% WO3 and 0.074% Mo. By applying the new technical achievement, for the raw ore containing 0.272% WO3, the seyrigite concentrate assaying 68.03% WO3 with a recovery of 77.56% was obtained in industrial production.INTRODUCTIONIn natural world, some kinds of scheelite minerals are rich in molybdenum. Molybdenum exists in the crystal lattice of scheelite in the form of isomorphism, and the scheelite is changed to be seyrigite (Ca[(W,Mo)O4]) (Ma, Bian, & Wang, 2013). The content of MoO3 in seyrigite varies from 2% to 10% usually, the content of MoO3 in some of the seyrigite even reaches 34%. The flotability of seyrigite is weak (Zhang, 2007), and the seyrigite is difficult to be recovered by flotation with common collectors and regulators. One scheelite mine in Anhui China, which is a skarn type seyrigite mine, has not produced qualified concentrate yet since 3 years it has been built due to the limit of beneficiation technology. Therefore, it is necessary to conduct research on the collectors with high efficiency and developing advanced processing flow for this kind of ore."

Jan 1, 2016

By W. R. Cowan

The availability of mineral aggregates for construction purposes is rapidly declining through inadequate resource planning. restrictive zoning and legislation , and competing land uses. The Geological Branch of the Ontario Ministry of Natural Resources has undertaken to provide aggregate inventory reports for all townships designated under The Pits and Quarries Control Act, 1971, and eventually for all towns hips in heavily populated areas. The reports contain maps and recommendations for extractive zoning by municipalities; of necessity only the largest deposits are given priority recommendations. It is intended that these reports should improve the resource planning in areas underlain by large aggregate deposits. The inventory is only possible because a concentrated effort has been made to map the Quaternary geology of populated areas over the last ten years. Future needs require that we develop methods to determine the extent of poorly defined and buried aggregates and that we look for natural alternatives.

Jan 1, 1978

By Yi-xin Zhoa

The characteristics of coal bumps are analyzed based on the microseismic data from No.8935 workface in Xinzhouyao coal mine, Datong Mining Group. The geology of this workface is characterized by the thick sandstone roof and coal seam, both with relative higher stiffness and strength. In order to investigate the mechanism and precursors of coal bumps occurred in No.8935 workface, the locations of microseismic, the relationship of microseismic energy and frequency and the spectrum of microseismic signals are analyzed. The result shows that the coal bumps in No.8935 workface were mainly induced by the seismic caused by roof failure. The coal pillar near the goaf is more easily to bump. The statistics results indicate that the coal bumps were mainly occurred in the gate road near the pillar, less than 50m ahead of mining face and located in the hard roof adjacent with coal seam. Moreover, the frequency, energy, b-value and frequency spectrogram of microseismic events were found to decrease before coal bumps. It was found that the frequencies of the microseismic events before coal bumps mainly concentrate upon 5~60Hz. The sudden decreasing of frequency and increasing of amplitude of microseismic events can be regarded as a precursor of coal bumps.

Aug 1, 2013

By P. J. Bourassa

Incorporated in 1957 under the laws of the Province of Quebec, Quebec Cartier Mining Co. undertook the development of its low-grade iron ore reserves located at Lac Jeannine in the southwest extremity of the Quebec-Labrador trough. This challenge comprised the construction of a 200-mile access road, two towns, a 191-mile-long railroad from Port Cartier to Lac Jeannine, a hydro-electric generating plant on the Hart Jaune River, and mining, crushing, concentrating and ancillary facilities to support a yearly production of 8.0 million tons of iron ore concentrates at 66% Fe. In order to meet increasing market demands for iron ore concentrates concurrently with the depletion of its Lac Jeannine reserves , Quebec Cartier announced, late in 1969, the first step toward bringing into production a new iron ore deposit, known as Mount Wright, located 70 air miles northeast of Lac Jeannine and 25 miles southwest of Labrador City, Newfoundland. In September 1970, the company announced its decision to develop and bring into production its Mount Wright reserves at an annual rate of 1 8.4 million dry long tons. The scope of this project included the construction of an access road linking the mine, the new town and Labrador City, Newfoundland, the extension of the railroad by some 86 miles, the construction of an ore concentrating plant with all the ancillary facilities, the development: of the mine, the construction of a pourer transmission line and a new town adjacent to Lake Daviault. The Mount Wright story is divided into five individual papers covering: (a) the history and development of the project; (b) the mine; (c) plant control by a process computer; (d) crushing, grinding and concentrating; and (e) the townsite of Fermont.

Jan 1, 1977

By Robert E. Loftus

"The author discusses the growth in the use of ocean-going bulk carriers for the transportation of mineral commodities, and predicts future trends. The various types of tonnage carriers are described, along with the special discharging gear used, the costs involved and the duties of some of the personnel.THE FIRST CONSIDERATION in planning the ocean transportation of minerals is the type of vessel to be utilized. The modern 'Bulk Carrier' bas proved to be the most successful vehicle for the purpose. I would there-fore like to describe this fleet in some detail and at-tempt to show the impact that the bulk carrier bas bad on the movement of bulk materials."

Jan 1, 1968

By Mauro Torres, Gabriel Zarate

"AngloAmerican used the extractant M5640 at Mantos Blancos and Mantoverde and uses PT5050MD at Los Bronces Division, which are aldoxime and modifier blends. In the first case, the modifier is the esther TXIB, while in the second case is the tridecanol TDA. It is a well-known fact that the extractant degrades while the modifier does not and with time the oxime/modifier ratio can change significantly, depending on the operating conditions of each plant.In order to evaluate the effect of this varying modifier content in the plant organic, especially in the organic losses, a complete metallurgical test work program was conducted at laboratory and pilot plant scale by Flomin SNF, a new extractant supplier. Results showed that the addition of an aldoxime without the modifier did not affect the chemical performance of the extractant, but there was a significant decrease in the viscosity and density of the organic.Based on the results obtained in the metallurgical program, it was decided to run plant scale tests at the SX plants of Mantos Blancos and Mantoverde. In these tests, instead of adding extractant to maintain the organic inventory, CuPROMEX 3406 which is an unmodified aldoxime was added until the original oxime/modifier ratio was reached. This was obtained after 6 months of operation and since then both plants are running with the extractant CuPROMEX 3302 both supplied by Flomin SNF.In the case of Los Bronces, the pilot plant work was completed and it is programmed to run similar plant scale tests. In this case, the oxime/modifier ratio increased and TDA will be added until reaching the original ratio.The plant results obtained at Mantoverde and Mantos Blancos, together with the pilot plant test results obtained at Los Bronces, are discussed in this paper."

Jan 1, 2016

By H. H. Bleakney

The merit of reduction-in-area as a criterion of quality in metals is shown to lie in its influence on breaking stress, but the virtue of elongation is not easy to find. In order to assess the value of elongation, either as a measure of quality or as a guide to design, it will be necessary to separate the overall de-formation occurring in tension tests from the localized deformation associated with localized reduction in area. The obstacles to a successful solution of this problem have been shown to be more formidable than is generally appreciated, and a new solution to the problem has been suggested. This solution involves a de-vice by which an electric circuit is broken when the particular value of strain is reached that is to be taken as the point of separation between general and localized deformation. The report presents results from a number of tests on both low-carbon and alloy steels. These results indicate that the selected criterion of separation is accurately identified by the proposed method; that it

Jan 1, 1962

By E. Herrera Alarcón, L. Mariscal Samaniego

The Teniente Converter (wet charge type) was commissioned in august 1995 and was designed to smelt 744 tpd (metric tons per day) of dry copper concentrates. Its products are white metal (73% Cu) that is sent to the Peirce Smith converters, slag that is cleaned in Reverberatory Furnaces and the process gases that are sent to the Sulfuric Acid Plant. Since its start up, the Teniente Converter smelting capacity was increased 1.6 times, from 800 tpd to 1,280 tpd using 33% oxygen-enriched air, and reaching an operative availability of 97%. By the other hand its campaigns have reached a record duration of 530 days without hot patching tuyeres and a partial refractory lining repair in the last four campaigns. This paper describes the most relevant improvements, as well as the strategies that had been used to reach these achievements.

Jan 1, 2007

By P. T. O'Kane

The PLATSOL® process, initially developed for the treatment of the NorthMet Cu/Ni/PGM concentrate, has seen over the recent years its applicability extended to include numerous other Cu/Ni concentrates of the same type, as well as other precious metals-containing feedstocks. However, several concentrates were found refractory to the typical PLATSOL® conditions, more particularly so the platinum. Attempts to extend those conditions, such as higher temperatures (250°C), longer retention time, increased oxidation conditions, higher chloride additions, were not successful. Detailed mineralogical investigation of those PLATSOL® leach residues indicated the main refractory mineral to be cooperite (PtS). Further metallurgical investigations showed that a thermal pre-treatment of the concentrate effectively unlocked the refractory platinum minerals for the subsequent leach. Temperatures between 400 and 750°C were tested, with the optimum being found around 650°C. The kinetics of the pre-treatment process were fast, and one hour at temperature proved sufficient. Under those conditions, PLATSOL® extractions were re-established around 95% for both platinum and palladium. From a mineralogical examination of the calcine, it was shown that the effect of the pre-treatment was to transform the cooperite and other refractory sulphides into metallic platinum and alloys, amenable to the PLATSOL®. The implications of the pre¬treatment step for the processing of PGM concentrates arc briefly discussed.

Jan 1, 2004

By A. Takala, H. Cline, D. Girard

"This article describes the project development and successful implementation of a particle sorter at the Kensington mine. The Kensington underground gold mine and associated milling facilities are located within the Berners Bay Mining District on the east side of Lynn Canal about 45 miles north-northwest of Juneau, Alaska. The paper describes the project from concept, through the development phase, including test work confirming feasibility, to a discussion of operational data and includes shared experiences from operation and maintenance. The project has proven successful in recovering gold that was previously lost to the waste dump and has already resulted in a positive return on investment. The payback was achieved in less than one year.INTRODUCTION The first paragraphs of this paper describe Coeur Mining and the Kensington Mine, its history, geology, mining operation and mill. The second part of this paper gives a quick introduction to sensor-based sorting in general and X-ray transmission sorting (XRT) in particular. This article does not cover costs or economic impacts apart from the pay-back period for the investment at Kensington. Interested readers find more in information on this in the literature (Kleine & Wotruba, 2010; Robben, 2013). Since the publication about XRT sorting at TGME in Pilgrim’s Rest (Kleine, Riedel, Ketelhodt, & Murray, 2010), this is the first time that a comprehensive data set on gold ore sorting using XRT is published. Following chapters highlight the aim of the project for Coeur Kensington, project development through testing and operation before concluding. ABOUT COEUR MINING’S KENSINGTON OPERATION Coeur Mining is the largest U.S.-based silver producer and a significant gold producer with five precious metals mines in the Americas employing approximately 2,100 people. Coeur produces from its wholly owned operations: the Palmarejo silver-gold mine in Mexico, the San Bartolomé silver mine in Bolivia, the Rochester silver-gold mine in Nevada, the Kensington gold mine in Alaska, and the Wharf gold mine in South Dakota. The Company also has a non-operating interest in the Endeavor mine in Australia in addition to royalties on the Cerro Bayo mine in Chile, the El Gallo complex in Mexico, the Zaruma mine in Ecuador, and the Correnso mine in New Zealand. In addition, the Company has two silver-gold feasibility stage projects—the La Preciosa project in Mexico and the Joaquin project in Argentina. The Company also conducts ongoing exploration activities in Alaska, Argentina, Bolivia, Mexico, and Nevada. The Company owns strategic investment positions in several silver and gold development companies with projects in North and South America."

Jan 1, 2017

By A. H. C. A. Zimmerman

WE have just heard what must be regarded as a thoughtful, constructive and somewhat painful analysis of the financial function of our industry. While thinking about this, it is interesting to reflect on the conditions which have stunted the growth of the financial side of our affairs. Mining must be regarded as a wealthy business. •while immeasurable grub takes and development budgets have been lost, there can be little argument that a productive ore-body nearly always produces the type of wealth that breeds some extravagance. I recognize that this statement can be attacked from many sides, but an historical comparison with a commercial enterprise involving similar investment will demonstrate what I mean. However, these old times are be-ginning to disappear for a variety of reasons. High amongst these are: ( l) Increased costs of exploration. (2) Remoteness of many new finds. (3) Fixed or declining metal prices (particularly when expressed in constant dollars). ( 4) Constant demands for higher wages.

Jan 1, 1962

By Peter C. Jones

Owing to the inadequacy of the ore transport system at Cassiar in the late 1960's, a new facility was required. This paper traces the various alternatives considered and gives a description of the tram line as installed. The problems encountered, changes made and future modifications are discussed in detail, together with the effects these have on maintenance and operations.

Jan 1, 1978

By E. J. Sides

In this paper, the argument is put forth that the codes used for public reporting of mineral resources and mineral reserves have some significant limitations with regard to the information provided to investors on the short- to medium-term value of mining properties. Such limitations include a) failure to explicitly incorporate a time element and b) failure to state explicitly the quantity and quality of mineral product that will be produced for sale. A time-value framework for reporting mineral assets is proposed in order to overcome these limitations. The proposed system is based on two classification axes: a) an X-axis representing time in years during which the value of the asset is likely to be realized and b) a Y-axis representing the value identified by a mining or exploration company\u2019s activities. The potential benefits of this system are discussed, including the ability to incorporate factors, such as permitting and construction times, directly into the magnitude of the reported mineral assets. The proposed framework would assist in the standardization of mineral assets reporting in such a manner that they could eventually be more readily included in financial statements. Year of Publication: Not explicitly mentioned in the document.

Jan 1, 2010

By D. H. Ryan, J. T. Graham, A. Navarra, J. A. Finch, S. Somot

Pyrrhotite (Po) is widely considered to be the most significant mineral in the self-heating of sulphides. It is therefore desirable to determine the amount of Po in mineral samples. This is commonly accomplished through x-ray diffraction (XRD) or quantitative evaluation of materials by scanning electron microscopy (QEM-SEM). This paper introduces another quantitative method based on Mossbauer analysis that requires limited sample preparation and has the additional potential to detect the sulphur/iron ratio within Po. The technique is explored using pentlandite/pyrrhotite mixtures.

Jan 1, 2009

By Jeff Smith

Agenda About NORTHPARKES The NEED The INITIATIVE The SEARCH The PRODUCTS The SOLUTION The RESULTS The Northparkes copper-gold mine in Central Western NSW commenced operations in 1994. Copper concentrate is produced and shipped to smelters in Japan, China & India under long term contracts with spot sales to other Asian countries.

May 1, 2006

By Adam Moore, Ryan Gillespie, Jarrett Quinn, Audrey Walters, Peter Radziszewski

"Vale Long Harbour Processing Plant (LHPP) was designed to process Voisey’s Bay nickel concentrate into finished nickel and associated copper and cobalt products. The plant includes a secondary grinding circuit comprising two Stirred Media Detritors (SMDs) operating in parallel. The ultrafine grinding circuit was designed to process concentrate at a rate of 33 t/h and produce a ground product (P80) of 20 µm to feed the leach circuits. Start-up of the grinding circuit at LHPP was undertaken in December 2014.The objective of this paper will be to describe the design, commissioning, start-up and performance of the secondary grinding circuit with a focus on the two Metso SMD-355-C mills. Following a brief overview of Vale’s LHPP and the SMD technology, the paper will review the design of the SMD secondary grinding circuit from lab tests through to scale-up performance prediction. This will be followed by the results of circuit commissioning outlining some of the issues raised and addressed after which SMD performance will be outlined. Specifically, the SMD circuit grinding performance will be examined since start-up which will include the effect of media size and wear on grinding. Furthermore, impeller wear will be examined by determining initial “shear volume” and worn “shear volume” as well as its effect on mill power and the means to maintain it. The paper closes with a discussion on grinding performance."

Jan 1, 2016

By Waldemar W. Koczkodaj, William O. MacKasey

Abstract - A consistency-driven pairwise comparisons method for mineral potential assessment is presented, using a simplified case of volcanic-associated massive sulfide type deposits as an example. Geological, geochemical, and geophysical criteria are considered on two levels: local and regional. The local geological criteria are subdivided into stratigraphy, lithology, alteration and/or mineralization, and structure. The concept of geomerit index and a procedure for computing this index are introduced. The method of consistency-driven pairwise comparisons can be combined with other quantitative and qualitative assessment methods, enhancing them by incorporation of nonmeasurable geological criteria (e.g., stratigraphy or lithology) and by computation of weights. The consistency-driven approach allows experts to refine at-times subjective judgments concerning exploration and land-use planning, and contributes to the improvement of mineral-potential assessments.

Jan 1, 1997

By Waldemar W. Koczkodaj, William O. MacKasey

A consistency-driven pairwise comparisons method for mineral potential assessment is presented, using a simpli?ed case of volcanic-associated massive sul?de type deposits as an example. Geological, geochemical, and geophysical criteria are considered on two levels: local and regional. The local geological criteria are subdivided into stratigraphy, lithology, alteration and/or mineralization, and structure. The concept of geomerit index and a procedure for computing this index are introduced. The method of consistency-driven pairwise comparisons can be combined with other quantitative and qualitative assessment methods, enhancing them by incorporation of non-measurable geological criteria (e.g., stratigraphy or lithology) and by computation of weights. The consistency-driven approach allows experts to re?ne at-times subjective judgments concerning exploration and land-use planning, and contributes to the improvement of mineral-potential assessments.

Jan 1, 1997

By W. M. G. Heeley

In the province of Alberta the coal measures dip at so many different angles, between the horizontal and the vertical, that many different systems of haulage are in use. I will, however, only touch briefly upon the general -systems in use, and devote the major portion of this paper to a discussion of endless-rope haulage and its adaptibility to various conditions in coal mines; dealing in particular with the endless-rope haulage that was installed at Brule during the month of August 1923. In coal seams that are approximately level, and newly opened, hand-putting or tramming from the face is the cheapest, but when the mine is further developed tramming is out of the question, and the use of ponies is the next consideration. The time arrives, however, when mining reaches a point where the economical haulage of coal by horses cannot be done profitably, and then some system of mechanical haulage must be installed. The installation of any system should be carefully considered before any particular type of haulage is adopted, because a great deal depends upon the grade or dip of the seam. Motor haulage is impossible to operate profitably on a grade of over 6 per cent and, while it is possible to use ponies, on short runs, up to 9 per cent, some other means of main and secondary haulage must be installed when a 9 per cent grade, is exceeded. I will, therefore, deal first with secondary haulage, because even though a main haulage is established, secondary haulage can be used to feed the main haulage.

Jan 1, 1925