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By J. L. Jobe

In planning the operation of a new mine or new sections of an operating mine, due provision must be made for the ultimate recovery of as much of the seam as is consistent with safety and economic principles. Each mining district and, indeed, each seam, especially in mining under submarine conditions, has individual problems which render hard and fast rules under all conditions of mining impossible. However, certain basic principles can be applied to all seams under specific conditions. In all mines, the two basic methods of mining, 'longwall' and ?room-and-pillar? or their variations, can be adopted, but certain fundamental factors must be analyzed before either method is finally applied to the extraction of the seam. The factors which enter into the successful, safe, and economic extraction of all seams are, briefly stated, as follows: (1) Character and thickness of the seam. (2) Character of the floor and immediate roof of the seam. (3) Composition, strength, and thickness of the overlying beds to the surface. (4) The depth of cover to the surface or sea bottom. (5) Conditions under which the seam is mined (land or submarine area). (6) Pitch of the seam. (7) Economic value of the seam. (8) Mining laws.

Jan 1, 1947

By William E. Roscoe

"Mineral exploration properties are those on which an economically viable mineral deposit has not yet been discovered. Such properties are bought, sold, optioned and joint ventured on the basis of their perceived potential for the existence and discovery of a viable mineral deposit. The intrinsic value of an exploration property is therefore based on the exploration potential. One measure of the exploration potential is the amount that can be justified to spend on exploration for a viable deposit.The appraised value method uses a cost approach to value exploration properties. It is based on the premise that an exploration property is worth the meaningful past exploration expenditures plus warranted future costs to test remaining exploration potential. Results of past exploration work are analyzed in order to retain only those past expenditures that are productive in terms of identifying remaining potential. Warranted future costs comprise a reasonable exploration budget to test that potential.INTRODUCTIONThe purpose of this paper is to describe a cost approach to the valuation of mineral exploration properties and to provide some valuation examples. The particular cost approach described is the Appraised Value Method, which is best applied to mineral properties at the exploration stage.At present there are no comprehensive regulations or guidelines in Canada which specify what approaches and methods to use for the valuation of mineral properties. In this paper, the Appraised Value Method described is one method that the writer considers to be accepted industry practice for mineral properties at the exploration stage.Mineral properties are valued for a number of reasons, including mergers and acquisitions, non arm's length transactions, pricing of initial public offering of stock, support for property agreements, litigation, expropriation, and insurance claims."

Jan 1, 2003

By Thomas Genty, Pascal Marcotte, Matthew Gillman, John Baechler

Elevated concentrations of ammonia nitrogen is a common characteristic of mine impacted water and generally results from the dissolution of undetonated explosives (i.e., Ammonium Nitrate and Fuel Oil and emulsion explosives) by contact water. Several active water treatment technologies are commercially available to remove ammonia nitrogen, but reduction of active treatment demand by promoting natural attenuation is considered best industry practice. In this paper, the results of laboratory-scale and full-scale trials of a semi-passive approach (i.e., enhanced algae growth) to remove ammonia nitrogen at the Meliadine mine are presented. Phosphorus was found to be the limiting factor to algae growth at the mine site. The addition of various concentrations of phosphorus was first tested at a laboratory scale. The samples were exposed to in-situ conditions, and ammonia nitrogen removal rates ranging from 40% to 93% were achieved over a period of 24 days. This paper also presents the methodology and results of an in-pond treatment during which a 50% ammonia nitrogen removal rate was observed after 68 days. The studied mine site uses breakpoint chlorination as its primary treatment approach for ammonia nitrogen removal. The results presented in this paper show the potential of using enhanced algae growth as a pre-treatment method, subsequently reducing the quantity of chemicals required for operating the breakpoint chlorination plant. This potential requires further investigation and additional trials are currently under evaluation.

Jan 1, 2023

By T. S. Li, D. Ilievski, I. Livk

Micromixing of the fluid and the particulate phases in a continuous gibbsite precipitator was investigated for three different micromixing states, namely maximum mixedness (MM), complete segregation (CS), and maximum mixedness of the fluid but complete segregation of the particulates (MMF-CSP). The influence of the micromixing on continuous precipitation of gibbsite was studied at different precipitation conditions via simulation. Three different cases were considered with respect to the precipitation kinetics: (1) gibbsite secondary nucleation is favoured with slow crystal growth and agglomeration rates; (2) gibbsite crystal agglomeration and growth are dominant mechanisms with secondary nucleation suppressed; and (3) gibbsite crystal growth is the only relevant phenomenon. Simulation results for the cases (1) and (3) showed that the crystalline products for both the MM and MMF-CSP micromixing states were very similar, but the product obtained from the CS micromixing state was considerably different. This indicates that at those precipitation conditions the fluid micomixing has the dominant effect on the product properties, and the particulates micromixing effect is insignificant. However, when operated under the conditions of fast crystal growth and agglomeration kinetics, i.e. case (2), both the fluid and the particulates micromixing were found to affect the precipitation process, resulting in a significantly different product. Computational Analysis in Hydrometallurgy 35th Annual Hydrometallurgy Meeting held in conjunction with the 44th Annual Conference of Metallurgists ofCIM Calgary, Alberta, Canada Edited by

Jan 1, 2005

By D. Raicevic

Interest has recently been revived in the recovery of tantalum from the Bernie Lake pegmatite deposit. A gravity concentration process was developed to give satisfactory recovery and concentrate grade. The application of high-intensity magnetic separation was also stud1ed. A pilot-plant investigation that confirmed the laboratory testing and provided a commercial-grade concentrate 1s described.

Jan 1, 1968

By B. Meddings, O. J. I. Evans

"This paper is mainly concerned with the present and probable future role of hydrometallurgy in the production of base metals.The economic and technological bases of the hydro-metallurgical plants built and operative in the mid-fifties are compared to those in production in the mid-sixties. The trends observed are extrapolated and some estimates made concerning the probable size and type of hydrometallurgical plants which will be operative in the mid-seventies.The impact of emerging socio-economic factors such as pollution control and the market demand for specialized metal products which favour hydrometallurgical recovery processes are also discussed."

Jan 1, 1971

By Fred E. Gray

The mill of Bralorne Mines, Limited, is located on the government highway in the Bridge River mining district of British Columbia, approximately fifty miles northeast of Shalalth, the shipping point on the P.G.E. railway. Prior to 1931, the property now owned by Bralorne Mines, Limited, was operated by Lorne Gold Mines, Limited. During the early operation of the mine, the ore had been treated at various times in one of three small amalgamation mills on the property. With the succession to ownership by the Bralorne Mines, Limited, work was started on construction of a new mill of approximately 100 tons capacity per day. The new mill was put into operation in the month of February, 1932, and since that date has been in continuous operation, milling an average of slightly over 3,000 tons of ore a month. The ore treated in the Bralorne mill is a gold-bearing quartz containing a very small amount of silver. About 75 to 80 per cent of the gold is in the form of free gold, the principal remaining portion being intimately associated with pyrite and arsenopyrite. The gangue rock is quartz, together with varying but relatively small amounts of altered diorite or albitite. In some of the ore, usually the higher grade portions, there is also considerable talc, which forms much slime in grinding. The mill is situated near the portal of the main haulage tunnel and the ore is received directly from the mine ore-trains, which dump on to the grizzly over the coarse-ore bin of the crushing plant. Figure 1 shows the flow-sheet of the mill as it is now being operated. Various changes have been made in the flow-sheet and in the reagents since the commencement of operations, and doubtless minor changes will continue to be made in order to increase the efficiency of the mill. Among the more important changes were those from two-stage to single-stage grinding, and from amalgamation plates to blankets. The change in the crushing was made because too much crushing was done when both primary and secondary mills were employed.

Jan 1, 1933

By R. L. Bruening, L. Navarro, Izatt. S. R., R. Adiga, R. M. Izatt, N. E. Izatt, A. Sharma, N. R. Patel, B. V. Rao

Bismuth is a notorious contaminant in the electrolytic refining of Cu that can cause cathodes to fail to meet ASTM International standards and not be suitable for use in Cu rod and other downstream products. Bismuth can significantly decrease electrical conductivity, decrease the mechanical strength of the annealed wire, retard recrystallization, and sometimes induce hot shortness during the hot rolling process in the production of rod. As a result, the control of Bi in the refinery tankhouse must be carefully managed. This paper describes how SuperLig® Molecular Recognition Technology (MRT) is being used for Bi removal at the Birla Copper Dahej Copper refinery. The operation of the SuperLig® MRT Bi removal plant is described and data on Bi removal efficiency are presented. INTRODUCTION Hindalco’s Cu division, Birla Copper, operates one of the largest Cu refineries in the world at Dahej, Gujarat; India. The main feed for this refinery is produced at the company’s smelter. Due to its massive production capacity, this operation mainly relies on imported Cu concentrates resulting in a variety of metals being carried out as impurities in the Cu anodes because pyrometallurgical technologies alone are not enough to remove them to the extent required. Metal impurities found in Cu ores include Fe, Zn, As, Pb, Bi, and Sb. During electrorefining, less noble metals dissolve in the electrolyte gradually increasing their concentrations creating the need for electrolyte control mechanisms that remove these impurities with varying degrees of success (Wang, 2004; Navarro et al., 2013.) Bismuth is one of the most significant impurities in a Cu refinery because it has the lowest ASTM product specification. This situation is critical because the Bi potential is very close to that of Cu making it possible to plate in the Cu cathode directly. Also, Bi can precipitate at high concentrations causing floating slimes and reduction of current efficiency (Ballinas, San Miguel, Munoz, & Gyves, 2003). Production of high purity cathodes from feed stock containing a diverse range of metal impurities becomes a major challenge in the refining of Cu (Izatt et al., 2015). In this work, the purification strategy followed by Birla Copper for the removal of Bi using a separation process based on MRT is presented, outlining the loading and stripping performance of SuperLig®83 and the benefits of using MRT over other lower selectivity methods where hazardous materials are produced instead of high purity products.

Jan 1, 2019

By A. Warczok

The computer simulator of slag cleaning in an electric furnace is based on a set of mathematical models describing heat liberation, the rate of slag reduction and gravitational coalescence of matte and metallic copper inclusions. The simulator consists of a mass and heat balances as a frame, in which the kinetic equations of the slag reduction and phase separation are incorporated. Friendly user-screen interface allows for dynamic control of process parameters in real time together with simulation of typical operations, such as furnace charging with liquid slag, solid reverts and coke, tapping out of the slag and matte, motion of electrodes and control of the transformer. The batch, semi-continuous or continuous process can be simulated. The process parameters are displayed and continuously recorded for further analysis. The computer simulator is a powerful tool for process optimization, training of furnace operators and the design of new slag cleaning installations.

Jan 1, 2007

By H. C. Cooke

"The Eustis mine, which was discovered in 1865, lies about 6 miles southwest of the city of Sherbrooke, Quebec, in lots 2, 3, and 4, range 9, Ascot tp. The mine was operated almost continuously from 1865 to 1937, under vanous owners.The ore was pyrite with varying amounts of chalcopyrite, a small amount of zinc blende and galena, and a low content in gold and silver. Parts of it ran quite high in copper, but the mine average would probably have been between 3 and 4 per cent. The high percentage of pyrite made it profitable to separate the ore into a copper concentrate and a pyrite concentrate. The latter was shipped away for manufacturing sulphuric acid, or was treated in a plant erected in 1887 at Capelton by the Nichols Chemical Company.The ore is a replacement of mica schist, which in turn was formed by the shearing of rhyolite flows. Ore also replaces the 'green rock', a term locally applied to carbonatized mica schists. The ore contained numerous 'horses' and smaller fragments of country rock, in all stages of replacement, ranging from those whose character was quite distinct to those whose ancestry could only be detected by an indefinite banding preserved in the sulphides."

Jan 1, 1954

By O`Donnell. P. J.

THE modern coal cutter is a highly developed, and to a certain extent a somewhat complicated, machine. The requisite power to cope with conditions as found must be generated by the motor with due regard to limitations in the matter of dimensions and weight. This imposes the necessity of relatively high speeds of rotation. Any factor external to the machine proper which tends to reduce the load on the motor and gearing is most important. Experience has proved that close attention to the question of cutter-chain details undoubtedly results, in practically every coal-cutting operation, in increased efficiency and reduction of power and maintenance costs. The chain is the unit of the coal cutter which most greatly affects the economical operation of the machine, and only by due consideration of conditions and by the proper selection of the right chain can best results be expected; also, intelligent care of the chain while in operation is essential if it is to give its best service. The chain is the part of the machine that carries the pick boxes or blocks, which are connected to each other by a pair of chain links. The power to drive the chain is trans-mitted by a sprocket. The chain runs in guides supported by a rigid member called a 'jib'. Figure 1 shows the various parts mentioned. The first requirement of a chain is that it cut the coal as fast as possible. The second is that it do so economically. Economy of cutting can conveniently be divided as follows: (1) Economy in power used. (2) Economy in pick life. (3) Economy ' in chain life. ( 4) Economy in jib life. (5) Economy in labour for maintenance.

Jan 1, 1936

By W. R. Dodge

THE growth and development of the assay department of the Hollinger Consolidated Gold Mines, Limited, is a similar story to that of the mine itself. As the mine developed and enlarged, so also increased the demands upon this department, necessitating an increase of capacity for fire assaying and a widening of the scope of work to include chemical analysis, metallurgical tests, research, and screen analysis. The yearly total of determinations, taking an average for the past six years, is approximately 350,000. The major portion of this figure represents fire assaying for gold and silver, being approximately 950 fire assays per day. The assay department occupies the ground floor of the administration building and covers approximately 4,000 square feet of floor space. Ready access is had by motor truck and electric railway for the delivery of samples and the removal of crushed rock and rubbish. The combined weight of all sample rejects amounts to about 5,000 lb. per day, which is sent to the mill bins. There are six departments, each occupying a separate room-grinder room, fluxing room, furnace room, parting room, weighing room, and flux-mixing and storage room.

Jan 1, 1931

By R. C. Reed, A. Akhtar

Oxidation of the third generation cast single crystal, nickel-base superalloy CMSX-10 is examined using isothermal tests at 900°C and 1000°C for times ranging from 20 hours to 100 hours. X-ray diffraction, scanning electron microscopy and energy dispersive secondary X-ray analysis were used to characterize the microstructure. It was found that the external scale formed at 1000°C is made up of (Ni,Co)O and the spinel NiCo2O4. The (? + ? ') microstructure of the superalloy transforms into the intermetallic (3 phase prior to the onset of internal oxidation. Internal oxidation results in the formation of (Ni,Co)Ta2O6 and (Ni,Co)WO4. No evidence was found for the formation of alumina (Al203), and the spinels NiCr2O4 and NiAl2O4 in this third generation superalloy. Results of the laboratory investigation are compared with those of an aero-engine turbine blade removed from service and examined earlier.

Jan 1, 2004

By Kimberly Morrison

Strategically located within the Uravan Mineral Belt District of western Colorado, the Piñon Ridge Project is the first new uranium mill being proposed for construction in the United States in over 25 years. In 1992, dramatic changes to the US regulatory environment for uranium ore processing occurred making regulatory compliance an increased challenge for a new facility. Proposed as a 6.3 million tonne uranium milling operation, the mill will receive ore from a number of mines in the region. The project includes design and permitting of a uranium/vanadium processing facility, tailings cells, evaporation ponds, and ore stockpile pads. The focus of this paper is to provide an overview of the US regulations and how these regulations were applied to design of the mill facilities, as well as provide a status update on the project as the mill license application was submitted to the Colorado Department of Public Health and Environment (CDPHE) in November 2009.

Aug 1, 2010

By R. A. L. Drew, J. P. Immarigeon, F. Jalilian, M. Jahazi

In the present work TLP bonding of Inconel 617 is investigated. The influence of the main processing parameters i.e. time and thickness of the interlayer were studied with optical and scanning electron microscopy. Boron containing interlayers with two different thicknesses were used and the influence of various holding times from 5 min to 24 hours on the microstructure of the bond region was investigated. The results indicated that, for the testing temperature of 1065°C and holding times above 2 hours with an interlayer of 25.4 microns thick no liquid phase was observed. The same phenomenon occurred only after 6 hours for a 76.2 microns thick interlayer. Precipitate growth started at grain boundaries and continued inside the grains. The composition, size and morphology of the precipitates were studied using electron microprobe analysis. No noticeable changes were observed in the grain size of the base metal with increasing holding times.

Jan 1, 2004

By B. H. Weber

"Industry generally has become noise-conscious and is realizing that damage to the human ear is expected to become more costly than any other compensation. Noise control has been recognized as a necessity and, fifteen years ago, in co-operation among different countries, inter-national organizations were set up to co-ordinate measures against dangerous noise and the development of silencing devices began. Rock drills for underground operations were particularly scrutinized because of the explosive nature of the noise developing from air escaping from exhaust. This paper describes the results and the present stage of development in the reduction and control of noise on rock drills, with special application to their use in mines."

Jan 1, 1970

By Sepulvedam Jaime E., Levi Guzmán Rivera

"Grinding media consumption rates and their dependence on key operating conditions in semiautogenous grinding mills is analyzed on the basis of a detailed mathematical model recently developed by Moly-Cop´s specialists which describes and takes into account the three primary media consumption mechanisms, namely: abrasion/corrosion, surface spalling and impact ball breakage. The influence of key mill operating conditions – such as ball filling, discharge grate opening, mill speed, lifter profile, and ball quality – on their corresponding grinding media consumption rates is explored via a variety of model simulations, discussing in every case the independent contribution of each of the indicated consumption mechanisms to the estimated total ball consumption rate.INTRODUCTIONA thorough understanding of the independent contribution of each grinding media wear mechanism is extremely important, especially in semi-autogenous grinding (SAG) operations where macrowear (spalling) and ball breakage cannot be ignored or neglected. The high impact conditions imposed in modern SAG milling environments has created serious challenges for grinding media manufacturers since their products must be able to perform with minimal breakage and surface spalling.GRINDING MEDIA WEAR MECHANISMFor SAG milling operations, at least 3 different mechanisms have been identified as the main contributors to the observed overall grinding media consumption, here referred to as: abrasion / corrosion, ball breakage and surface spalling.Wear by Abrasion/CorrosionThe abrasive/corrosive wear mechanism has been discussed in depth in previous publications (Benavente Hector, 2007; Guzman Levi, 2014; Sepulveda and Morrow, 2014). The most widely accepted approach to mathematically characterize the consumption (wear) kinetics of grinding media in rotary tumbling mills is known as the Linear Wear Theory (Prentice, 1943; Norquist, 1950; Sepulveda, 2004) which claims that—at each instant 't' after a grinding body enters the mill load—the rate at which the body loses weight is directly proportional to its surface area exposed."

Jan 1, 2016

By Samuel O. Akande

"Gold occurs as native metal, in electrum, and in a telluride mineral in quartz carbonate veinlets of three vein systems at the Ross Mine, northern Ontario. The 14 Vein System is made up predominantly of concordant veinlets within layered ankeritic dolomite stratabound by, and conformable with, andesite tuff Individual veinlets contain pyrite, sphalerite, galena, chalcopyrite, tennantite, pearceite, proustite, native gold and electrum in a matrix of quartz, dolomite, ankerite and calcite. The 2B Vein System is made up of both concordant and discordant veinlets within andesite tuffs. The veinlets contain pyrite, chalcopyrite, sphalerite, bornite, tennantite and free gold in quartz, calcite and dolomite. The 18 Vein System is comprised of stockwork veinlets in and around intrusive syenite which has both sharp and gradational contacts with enclosing andesite tuff The veinlets contain pyrite, chalcopyrite, bornite, chalcocite, native gold and calaverite. Sulphide and silicate minerals in veinlets and wall rocks are stable assemblages for the regional metamorphism of greenschist rank. ,The 14 Vein System is interpreted as a metalliferous siliceous carbonate chemical sediment, the components of which were leached from the underlying volcanic rocks by convecting sea water and subsequently deposited on the sea floor between the extrusion of flows and pyroclastic rocks. Subsequent regional metamorphism and intrusions remobilized and redistributed the syngenetic stratabound material into dilatant fractures in adjacent tuff, as in the 2B and the 18 vein systems."

Jan 1, 1982

By Hong Zhong, Shuai Wang, Fangxu Li, Guangyi Liu

"The flotation performances and adsorption mechanisms of a-hydroxyoctyl phosphinic acid (HPA) to malachite, cassiterite and wolframite were investigated by micro-flotation tests and X-ray photoelectron spectroscopy (XPS) analyses. The micro-flotation results indicated that compared with styrene phosphonic acid (SPA), diphosphonic acid (DPA), benzohydroxamic acid (BHA) and salicylhydroxamic acid (SHA), HPA exhibited excellent collecting power to the three oxide ores. In addition, HPA showed superior selectivity against hematite, tourmaline, feldspar and quartz. The results of XPS analysis demonstrated that HPA reacts with active species (M) on metal oxide by formation of P-O-M or P-M bonds.INTRODUCTIONIn mineral processing, flotation has been the main process for separation and recovery of valuable minerals from complex ores (Mei, 2013; Zhou, 2014). One of the key requirements in flotation process is to increase selectively the surface hydrophobicity of the targeted minerals by surfactant (known as collector in flotation) adsorption so that these mineral particles can preferably attach air bubbles in a slurry or pulp (Bai, 2004; Hankins, 2004). To anchor a solid surface selectively, special functional group are designed to adjust the interaction between the surfactant and the active sites of solid surfaces (Wu, 2006; Huang, 2014).Organic phosphorous compounds have strong affinity toward metals or metal oxides because they form more stable metal complexes than metal carboxylates (Pazik, 2001; Zheng, 1998). In mineral engineering, phosphorous compounds have been exploited as metal extractants and flotation collectors (Alguacil, 2002; Sun, 2008). Ni (2012) and Zhang (1998) introduced diphosphonic acid (DPA) as an effective collector for flotation of fersmite and niobite. Liu (1999) found styryl phosphonic acid (SPA) was a superior collector for flotation recovery of finely disseminated rutile ores. Gruner and Bilsing (1992) thought SPA was one of the best collectors for flotation recovery of cassiterite which could obtain a high-grade concentrates of more than 40% with high recovery values. Bulatovic (1999) investigated the flotation performances of phosphoric acid ester (PAE) to perovskite, ilmenite and rutile and found that PAE was an impactful collector for selective flotation of titanium minerals from complex ores in the presence of petroleum sulfate. However, a-hydroxyoctyl phosphinic acid (HPA) as a flotation collector for recovery of titanium ores were hardly reported in the previous literatures."

Jan 1, 2016

By A. R. MacLean

This mine is situated at Point Aconi, Cape Breton , Nova Scotia, and is a replacement for the 100-year-old Princess Collie ry. It is a slope mine which is the continuation of a s trip mine operation. There are fives lopes from the surface driven with Dosco Dintheaders - this marks the first time these machines were used in North America. There are four room -and-pillar sections, each equipped with a Lee Norse HH106 continuous miner, a "Top Dog" roof bolter and two Wagner diesel Teletrams. There are also two Eimco 913 diesel LHD's , which are used for clean-up in the mines. This paper describes the mining operations of this 800,000-tpy mine which, in less than a year and a half , has been developed to the stage where four sections are producing coal at the desired rate.

Jan 1, 1978