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By Joshua Cole, Joshua Sovechles, Christian Cardoso, Guillermo Bermudez, Martta Hirsi, Joshua Dettamanti, Rabia Abbasi

The implementation of technological advancements in flotation is key to optimize performance in mining operations. Consequently, flotation cell’s performance is highly dependent on the effectiveness of the mixing mechanism. A more efficient flotation mixing mechanism is likely to improve metallurgical performance and optimize energy consumption, which is the motivation for Metso’s journey to develop the latest iteration of FloatForce®. Looking to test the new design at plant scale, Metso approached the Kennecott Copperton concentrator, which is continuously looking for different venues to improve metallurgical performance. In this context, a test campaign was conducted to implement this new flotation mixing mechanism in their rougher circuit during 2024. The industrial trial consisted of several sampling campaigns assessing different operational parameters for comparison purposes around a 300m3 flotation cell. The effect of the new flotation mixing mechanism on the cell’s power draw was also studied. The results of this trial at Kennecott are presented in this paper. Overall new flotation mixing mechanism, FloatForce+ was seen to perform as well as the original FloatForce.

Feb 1, 2025

By T. Tamagawa

A gaseous chlorination process for hydrometallurgical treatment of a chalcopyrite concentrate was investigated. The overall process is visualized to consist of low temperature chlorination-selective oxidation, followed by aqueous chloride leaching and SX-EW for producing electrolytic copper elemental sulfur and ferric oxide. In this article, the chlorination phase of the processes is described. Initially, the chlorination behavior of chalcopyrite-concentrate micro-pellets was investigated using a small batch-type fluidized bed reactor. The optimum conditions thereby established was used in continuous chlorination tests. The chlorinated products thus prepared were used in the selective oxidation phase of the investigation.

Jan 1, 1999

S. R. Carter (Mount Isa Mines Ltd., Mt. Isa): I found many ideas to interest me in Haddon King's paper "Notes on Ore Occurrences in Highly Metamorphosed Precambrian Rocks" (Stillwell Anniversary Volume).At Mount Isa I have not been happy about some of the longstanding appreciations of the geological evidence as fresh data accumulated, and as more and more knowledge has been building up outside Mount Isa in recent years of sedimentary deposition of sulphides.Accordingly, I organized a small section of the Geological Department at Mount Isa at the beginning of 1958 under Senior Geologist, W. J. Murray to reappraise our geological record and investigate old interpretations and new ones that arise. The work is expected to take several years to complete, but it is hoped that sufficient will be done before then to permit the most plausible story on the ore genesis to be chosen. In the meantime, W. J. Murray has proposed, in a Company Report, that the.epigenetic features of the silver,lead-zinc deposits, which are essentially conformable with the shales, could have resulted from remobilized syngenetic deposits.Haddon King, on p. 159; has listed six assumptions that are required by a magmatic-hydrothermal theory of, origin for conformable deposits. It is interesting to consider the Mount Isa silver-lead-zinc deposits in terms of these requirements.My comments are listed in the same order as Haddon King's assumptions:(a) "The source of the constituents is magmatic and they have become available in successive waves of zinc-rich, lead rich, manganese rich, silver rich, etc, instalments in accord...

Jan 1, 1959

By R. Ressel

Keywords: ferrovanadium, thermodynamics, phosphorus Recyclable material is rapidly gaining in importance as a source of raw materials in industrialized countries. This is also the case in the production of ferrovanadium, where, increasingly, materials such as discarded capacitors, spent catalysts, slag, dust and sludge are used. As the V-content in the raw material varies greatly, the demands on process technology are very high. The share of perturbing elements depends very much on the source of the raw materials, which, in turn, makes a corresponding optimization of the various refining steps necessary. The raw materials are mostly available as oxides, which means that carbon, silicon or aluminium are used as reducing agents. Thermodynamic calculations were used to show especially the behavior of vanadium and phosphorus at different process conditions.

Jan 1, 2005

By Moskovits E. E

Spodumene was recovered from pegmatite by flotation in laboratory and pilot-plant tests using an anionic collector emulsion. A similar process applied to beryl pegmatite gave encouraging results.INTRODUCTIONOver the past two decades lithium and beryllium have aroused increasing interest in the metallurgical world. Both these light metals have potential uses in nuclear shielding and cooling and in lightweight alloys, and there is a growing demand for lithium chemicals for ceramics, air conditioning and lubricants. The use, technology and history of lithium has been surveyed by Schreck (1961).For many years, the only commercial production of lithium and beryllium was from pegmatite deposits amenable to hand cobbing. The most important minerals of these ores are spodumene and beryl, which are respectively lithium aluminium silicate and beryllium aluminium silicate. Norman and Gieseke (1940) investigated the treatment of lithium ores by froth flotation. The process of flotation of the pegmatite constituents away from the spodumene was applied commercially in 1951, and the operation has been described by Goter, Rainey and Hudspeth (1953). Subsequently, the flotation of the spodumene from the pegmatite was studied by Munson and Clark (1955) and Browning and McVay (1961), and this method has superceded the reverse flotation process commercially. Muskett, Tasker and Hobson (1962), in applying the method of Browning and McVay in pilot-scale tests, reported difficulty because of activation of quartz and felspar by iron salts introduced during milling of the ore.The flotation of beryl, reported by Ashton and Weir...

Jan 1, 1963

By R E. Myers, G N. Phillips

Many of the worldÆs larger iron ore deposits are hosted by rock sequences of Archaean to early Proterozoic age. Most models for the genesis of these deposits are influenced, either directly or indirectly, by the nature of the atmosphere at the time of their formation, and more specifically by the presence or absence of oxygen in the early atmosphere. Since the early-1950s, the geological literature suggests that the Archaean atmosphere was æreducingÆ, and that it may not have contained significant amounts of free oxygen until ca 2 Ga. There are many different definitions of the term æreducingÆ, but the criterion adopted here is whether crustal iron was limited to Fe2+, or whether Fe3+ was also widespread, ie was there scope for redox changes in the state of iron? Significantly, major Australian banded iron formations span this period of inferred atmosphere transition, eg Mt Goldsworthy, Mt Tom Price, Middleback Ranges. Geological evidence for a reducing Archaean atmosphere is both ambiguous and controversial (see review by Phillips, Law and Myers, 2001). Many earlier ideas (eg no Archaean redbeds; all very large iron ore deposits being post-Archaean) have been disproved by dating, whereas other evidence (eg homogeneous detrital gold grains, inferred palaeosols) has not withstood geological scrutiny. The interpretation of some data sets (eg inferred detrital uraninite and pyrite in some Archaean meta-sedimentary rocks) is still controversial. In fact, some lines of evidence now suggest that oxygen was present in the atmosphere well before 2.5 Ga (eg sulfates in the Pilbara craton, carbon distribution in clastic sedimentary rocks). An oxidising Archaean atmosphere has important implications for the development of iron formations. First, the atmosphere is an obvious potential source of oxygen to stabilise ferric iron minerals. Second, reduced fluids in equilibrium with ferrous iron are commonly inferred to transport iron in solution to the depositional site. The redox state of the atmosphere thus provides critical constraints on the solution chemistry of surface waters, effective transport paths for iron and particularly on viable precipitation mechanisms. Iron formations developed from fluids in equilibrium with the atmosphere also have the potential to provide important constraints on the evolution of EarthÆs early atmosphere. If an oxygenated atmosphere is a necessary condition for the development of iron formations, then the Archaean atmosphere must have been oxidising since at least 3.5 Ga. If the redox state of the atmosphere is not a necessary condition, then the time distribution of iron formations cannot be used to provide constraints on atmospheric evolution. Given these uncertainties, models for the genesis of iron ore deposits of Archaean or early Proterozoic age should not rely on a reducing atmosphere in the absence of independent evidence and the alternative of an oxidising atmosphere should also be considered.

Jan 1, 2002

By T. Gupta, T. Ghosh

Rare earth elements (REEs) and their compounds are essential in a multitude of mundane and sophisticated applications such as renewable energy technologies, catalysts, medicine, and defense applications. The global supply deficit could be attributed to the destabilization of REE market that has, as a result, incentivized indigenous production of REEs. Cost-effective and environmentally benign opportunities are being explored for the production of REEs from non-conventional mineral sources including coal and coal by-products to stabilize the supply chain. Coal from Healy coal mine and Wishbone Hill deposits in Alaska have been quantified for REEs and were found to possess elevated total REE concentrations as compared to world average levels (60– 70 ppm). The objective of the study was to concentrate the REEs in the froth phase by froth-flotation of the fine size fraction (< 75 μm). A Box-Behnken design of experiment was employed to ascertain the main and interaction effects of operational parameters on response variable by analyzing 3D response surfaces. Experiments were carried out to maximize REE recovery and concentration by modeling and optimization of three operating variables (frother dosage, pulp density (% solids), and collector dosage). Based on the results, the optimum flotation conditions for maximum recovery at an elevated concentration of REEs in the froth fraction was obtained at 4.2% solids and 32.7 ppm of frother dosage for Healy sample and 10% solids and 37.9 ppm of frother dosage for Wishbone Hill coal sample. The quadratic relationship between the input and response variable was found to be independent of collector dosage suggesting good surface hydrophobicity and floatability of the two coal samples.

By J. P. Josien, Didier C.

ABSTRACT: France now faces the closure of most of its mining sites. Surface instability risk may sometimes remain, especially where large underground voids exist. This paper illustrates the importance of failure mechanisms identification in order to define properly how to manage the residual risk. RESUME: La France fait aujourd’hui face à la fermeture de ses exploitations minières. Des risques d’instabilités de surface peuvent persister, notamment lorsque des vides résiduels existent au sein des travaux souterrains. L’article illustre l’importance que présente la nature des mécanismes de rupture potentiels dans le choix des mesures compensatoires à adopter pour gérer le risque résiduel à long terme. ZUSAMMENFASSUNG: In Frankreich stellt sich derzeit das Problem der definitiven Schliessung des meisten Bergwerke. In manchen fällen ist die Stabilität der Oberfläche nicht garantiert, speziell wenn unter Tage nicht verfüllte Hohlräume verblieben sind. Dieser Bericht zeigt die Wichtigkeit, bei der Auswahl geeigneter Langzeit-Risikomanagementmethoden, der verschiedenen Mechanismen mit denen ein eventueller Bruch an die Tagesoberfläche geraten kann.

Jan 1, 2003

By Ralph H. Espach

Wyoming contains many petroleum and natural-gas fields, and more than 250 geological structures have been mapped; however, only about 85 have been found (July 1938) to contain petroleum or natural gas, or both, in commercial quantities. To January 1938 approximately 434 million barrels of oil and 915 billion cubic feet of gas have been produced, and it was estimated that proved oil reserves in Wyoming amounted to 300 million barrels.&apos; The Salt Creek field, the largest in the Rocky Mountain area, alone has produced 64 percent of the State&apos;s oil and 46 percent of its gas. This field ranked thirteenth among the producing fields of the United States in total cumulative production as of January 1, 1938. On this basis it ranks with the Kern River and Huntington Beach fields of California and the Butler County fields of Kansas. The Salt Creek field has declined in relative importance; in 1937, while still the largest oil-producing field in the State, it produced 31 percent of the oil and 11 percent of the gas extracted from all wells in Wyoming.

Jan 1, 1941

By M. C. Bhulose

Paper written on project work carried out in partial fulfilment of B. Eng (Mining Engineering) degree The purpose of this project was to identify constraints that could occur in the current sub-decline shaft at Turffontein Shaft should an increase in production take place. Particular attention was to be paid to the transportation of men and materials and to the broken rock and ventilation capacity of the shaft. This project is an in-depth evaluation of the logistic capacity of the sub-decline system at Turffontein Shaft in order to determine by how much production can be increased in this area to replace tonnages from the vertical shaft area, where ore reserves are rapidly becoming depleted.

Jan 1, 2004

By A. Bascetin

One very important aspect of mining is deciding what material in a deposit is worth mining and processing, versus what material should be considered waste. This decision is summarized by the cut-off grade policy. The cut-off grade strategy for an open pit mine influences the annual cash flows and affects the net present value of a project. The optimization of cut-off grade strategy requires the knowledge of detailed operational costs, mining sequence, mining operation, processing, and product constraints, as well as the grade distribution of a given deposit defined by pit, phase, and different material types. Cut-off grade optimization algorithms have been developed in the past. The most common criteria used in cut-off grade optimization is to maximize the net present value (NPV). This paper describes the determination of a cut-off grade strategy based on Lane?s algorithm adding an optimization factor based on the generalized reduced gradient (GRG) algorithm to maximize the project?s NPV. The introduced algorithm is a windows based program developed at Virginia Tech that is based on a series of Visual Basic routines within a spreadsheet environment (Excel).The benefits of the methodology are demonstrated using a hypothetical case study. Keywords: Cut-off grade optimization, net present value maximization, generalized reduced gradient algorithm method.

Jan 1, 2007

By S. Hardy

The paper describes state of the art non-linear analyses of the pile groups that were employed during the raising of the 133m high triumphal arch which forms the centre piece of the new Wembley stadium in North London. The deformation behaviour of these piles groups was critical during the lifting process, due to the slendemess of the arch structure. The issue was made more critical by the high profile nature of the project. The results of Class A (Lambe (1973)) predictions of the pile group movements are compared with observed displacements and rotations which were accurately measured on site. To illustrate the importance of soil non-linearity on pile group behaviour, comparison is also made with pile group analyses which assume a linear soil stiffness.

Jan 1, 2006

By Alfred Weiss

Selecting a minicomputer is not unlike selecting a costly piece of mining equipment such as a truck, shovel, crusher, or conveyor belt system. A marked difference might lie in the frequency at which such selection takes place; another difference might be mine management&apos;s familiarity with mining equipment vis a vis a minicomputer. These basic differences might prompt a mining company to seek the aid of a consultant when selecting a minicomputer system. Advantages and Disadvantages The fundamental advantage of employing an independent consultant is that it provides management with a source of knowledge and breadth of experience not readily available within the organization. If the consultant has a minerals background, such knowledge and experience are further enhanced by actual experience in exploration, mining, and mineral processing. If the consultant has worked within a mining company, such hands-on experience is supplemented with a meaningful understanding of the client&apos;s business; this facilitates communication between the consultant and members of the client organization. The consultant has been, so to speak, "in the client&apos;s shoes." There are several other advantages. Since computer systems cut across organizational boundaries, the independent consultant may be able to move within the organization more easily than an inside staff person to collect necessary information. Also, detachment from any manufacturer should provide the client with an objectivity and a set of recommendations as near optimal as feasible. The principal disadvantages lie in the area of continuity and accountability. Once the consultant&apos;s report has been submitted and his recommendations implemented, a discontinuity might occur. Also, if implementation does not provide the desired results, the consultant might not be available to correct the situation or account for actions taken. Proper selection of consultant services, relative to kind and duration, and the consultant&apos;s method of operation, will often prevent many of these aftereffects. Services Offered The professional consultant can help a client: •Define and summarize information systems technology* needs; • Evaluate alternatives such as in-house capability and capacity, time-sharing, or service bureaus; • Prepare a formal request for proposal (RFP) to be submitted to vendors; •Evaluate vendor proposals; •Evaluate the economics of lease vs. purchase; and •Assist in the conversion and installation. Thus, consulting services may range from evaluating an existing system and upgrading to a larger piece of equipment, to selecting a new first-for-the-organization computer. First, Define and Summarize Needs Regardless of circumstances, the most valuable document required before equipment selection is the information system plan (I/S plan). It helps insure that the company&apos;s information needs are met in a cost-effective manner. An I/S plan is usually a comporient of the mining company&apos;s overall business goals. Since an I/S plan is a formal vehicle for establishing and communicating the direction the organization intends to take to satisfy information requirements needed to achieve goals and objectives, most initial systems services are likely to center around creating such a document or updating an existing document. The trend toward company-wide I/S planning is increasing in the mining industry; however, smaller scale efforts focused at the information systems needs to support an individual

Jan 11, 1981

By Sigurd L. Lamhauge, Karl Gunnar Holter, Svein E. Kristiansen

An innovative sprayable waterproofing membrane in combination with the traditional Nordic method of waterproofing with polyethylene foam sheets was used for the waterproofing of the tunnel. The sprayable membrane was integrated in the final sprayed concrete lining in a sandwich structure, hence constituting a composite water-proof lining based on sprayed concrete. The spray able membrane was applied in areas with small to moderate water ingresses, making up approximately 50% of the total area requiring waterproofing in the tunnel. State-of-the-art application technology with a computerized spraying robot was used. A consistent application of the required thickness at a high speed was thereby achieved.

Jan 1, 2007

By D. Brady

There are many examples, historical and recent, from the underground coal mining industry where during emergency response the response and ultimately the outcomes, could have been significantly improved if adequate systems had been in place for the collection and management of relevant information preceding the incident, the acquisition of information during the incident and the use of the information for risk mitigation and decision making purposes. The subject and process of knowledge management is possibly the most critical for would be rescuers of endangered coal mine workers, as it has been demonstrated at numerous coal mine incidents that a lack of or mismanagement of crucial information can be fatal for both the rescuer and/or the endangered coal mine worker. This paper will underline the scope and importance of robust knowledge management systems for emergency response within the underground coal mining industry and the process by which it is being achieved within the Queensland Mines Rescue Service and the NSW Mines Rescue Service.

Jan 1, 2012

By Brent Duncan, Doug Harding, Bob Stier

The 73rd Street Tunnel Project is part of “The Tunnel and Reservoir Plan” (TARP)also known as the Deep Tunnel Project, and is located in the Village of Bedford Park, County of McCook, State of Illinois. The project consists of a ø 4.42 meter × 2,060 meter long (14´-6? bore, 6,760 foot)tunnel. The completed tunnel is used as a bypass tunnel for the McCook Cup Reservoir Project. The project was awarded to Affholder Inc. of St. Louis, in 2000. The paper describes the project in which a new, high-powered open gripper type main beam machine was used in which high advance rates have been achieved using conventional muck haulage techniques. Features of the project include the installation of rock support consisting of counter-sunk rock bolts that are required to be pull-tested for strength per project specifications. Installation and testing of the bolts are done during the boring cycle. Muck haulage was done by conventional muck car train and hoisting at the construction shaft. As the site layout did not include a tail tunnel, the trains needed to be shuttled at the shaft bottom. Even with the bolting requirements and the muck haulage without a tail tunnel, the Affholder site personnel still achieved high advance rates on the 73rd Street Project.

Jan 1, 2003

By A. U. Miller

Protection against fire is a greater problem at a coal mine, than at an ordinary industrial plant. Generally mines are located in isolated districts and do not have the protection of city fire departments; consequently fire fighting aquipment must be installed by the mining company. Fire protection around a mine is just as essential as it is in the city.. and undoubtedly is more important if the fire should be underground where many lives would be endangered and all means of escape cut off. A surface fire can generally be attacked from any angle, but an underground fire can be attacked only as conditions will permit.. U. S. Bureau of Mines engineers have investigated many serious mine fires that undoubtedly could have been extinguished in incipiency if a fire extinguisher or fire hose and water had been readily available. In past years very little attention was given..to fire fighting equipment and organization around mines, but in recent years three gen a derde hange of opinion among many of those engaged in mining, and nearly all up-to-date mining companies now have some kind of fire protection about their mine Probably the first company in Illinois to install regular fire fighting equipment and effect a fire fighting organization at its mines, was the Madison Coal Corporation, which operates several mines in Illinois. The main office of this company is in Chicago and the general field office is at Glen Carbon, Ill.

Jul 1, 1930

The subject which I have chosen for my paper is one that I am sure has occurred to the minds of nearly every mining man on these goldfields at some time or other. I refer to the carrying out of hydraulic mining on a fairly large scale on some ofthe alluvial areas of the West Australian goldfields. There are many, no doubt, who have the question ready at the present moment, &quot;But where is the water coming from? &quot; However, the great difficulties in the way are not due to the want of natural facilities, but due to the fact that sufficiently large areas cannot be leased for this purpose under the present Mining Act. Now, ever since the inception of the West Australian goldfields there has been the old familiar cry when referring to some alluvial gully or flat, &quot;I wish I had a head of water to sluice that ground,&quot; but what seems an impossibility at times can be brought to a very great possibility by the use of a little thought and the expenditure of the necessary capital. This is so as regards West Australia with sluicing which, in spite of the its having so many detractors, can be carried out successfully in certain localities if the ordinary facilities on the part of the Govenment are given, and on the other hand the necessary capital is supplied. Alluvial gold areas, I propose now to draw your attention to first of all, the numerous alluvial areas that exist around Coolgardie, Kalgoorlie, Bulong, Kurnalpi and many other centres. Some of these areas have afforded fortunes inthe early days to the alluvial miner, and also afforded a living for years to many diggers&apos; by the use of the dryblowing...

Jan 1, 1901

By Richard P. Stahura

During the next five years, there will be a trend toward performing belt cleaner maintenance while the conveyor is in operation. Most mines and industrial sites that use belt conveyors have an in-house safety rule that the belt must be stopped before maintenance work can be performed on any belt-cleaning device. This is a good rule. Most cleaning devices are positioned against the belt with hardware that requires the service technician to reach or climb into the chute to change the cleaning blades. But this simple rule becomes more complicated as production demands require higher conveyor availability and provide fewer conveyor outages. In many cases, today’s conveyors are expected to be available 98% to100% of the time.

Jan 1, 1996

By William F. Daly, William H. Hansmire

Installation of initial tunnel support is often the most uncertain element of work in the design of, and a contractor bidding on, construction of a rock tunnel. The risks the construction contractor and owner assume are delineated to a great extent in the technical specifications portion of the contract documents. It is intended that this paper identify current practices for specifying initial tunnel support and the impacts each case has on the assignment of risks associated with providing the initial tunnel support. Examples of recently completed tunnel designs are given.

Jan 1, 1985