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By D. A. Livingstone

Abstract Golden Manitou Mines, Limited, nine miles east of the town of Val d'Or in northwestern Quebec, are presently milling, at the rate of 1,000 tons daily, a relatively complex 3.11-phide ore and producing, in decreasing order of value, zinc, silver, gold, lead, and copper. The products are a zinc concentrate, a silver-lead-copper concentrate, and a silver-gold precipitate from cyanidation. Although several independent pre-production metallurgical investigations into the treatment of the ore were carried out, current practice is different from any of the recommended methods and, while still leaving room for improvement, is considerably more effective than earlier performance. Flow-sheet developments from the commencement of operations in 1942 are dealt with briefly, showing the reasons for making numerous changes, the shortcomings of the various schemes tried, and, finally, covering data pertinent to present-day practice. From the recovery standpoint, silver has presented the greatest difficulty. The writer's association with the Company coincided with the start of production. Characteristics of the Ore The predominant metallic minerals present in the ore, in decreasing order of their abundance, are: pyrite, sphalerite, galena and chalcopyrite, with lesser amounts of argentiferous tennantite-tetrahedrite, arsenopyrite, covellite, bornite, and chalcocite. The sphalerite is mostly light in colour, sometimes colourless, and practically free from combined iron. Some of the sphalerite is very closely associated with minor amounts of pyrite, chalcopyrite, and galena. Pyrie is abundantly disseminated as medium to fine grains; more rarely it is massive and contains occasional grains of sphalerite, galena, and chalcopyrite.

Jan 1, 1952

By W A. James

The use of spectrographic semi-quantitative analysis has recently been of considerable value in establishing the geological relationships in a complicated orebody. The principal minerals found in the Mount Pleasant orebody are cassiterite, stannite, sphalerite, molybdenite, wolframite, chalcopyrite and galena, associated with arsenopyrite, pyrite and fluorite. In addition to the large number of minerals, a further com-plication is the non-uniform distribution of the economic minerals, with one mineral being the only one present in major amounts in one area and another mineral being predominant in another area. At the same time, all minerals are present to a minor extent throughout the deposit. This heterogeneity made it advisable to analyse all exploration samples thoroughly. Analysis by conventional means would have resulted in prohibitive costs. By the use of emission spectroscopy, however, it was possible to obtain, quickly and relatively inexpensively, a reasonably comprehensive picture of the orebody un-der investigation.

Jan 1, 1963

By R. K. Komarek, F. E. Jr. Briber, G. M. Hanson, Fred D. DeVaney, J. H. Blake, C. L. Matson, T. E. Ban, N. E. Shields, R. D. Frans, R. B. Greenwalt

Metallurgically, the term agglomeration is used to describe processes whose goal is to form balls, briquettes, nodules, flakes, or other sized shaped particles from loose, usually fine, incoherent particles. In practice it includes such varying processes as the briquetting of coal dust and other substances, the balling and induration (heating) of such nonmetallics as cement, fluorspar, lightweight aggregates, etc. It includes such widely used processes as the sintering of nonferrous concentrates, such as those copper, lead, zinc, etc. The agglomeration of specific nonferrous metal concentrates is discussed in detail in the section of this handbook devoted to that particular metal. Agglomeration processes are of particular value to the iron and steel industry where the nature of the primary reduction process, the blast furnace, requires for best results a burden essentially free of fines. This is a change that has taken place since about 1960. Prior to that time many fine unsized ores were fed to the furnace. The development of the pelletizing process gave to the industry a chemically controlled closely sized product that increased the produc¬tion rate and reduced the costs so much that unsized fines are seldom used in modem furnaces. Steel plants produce many fine sized waste products such as fine dust (fine ore coke and gangue) and mill scale. These products, which have a valuable iron content, are usually sin¬tered directly at the plant for reuse. Fine sized ore concentrates are usually pelletized at the mine and shipped as pellets to the steel plant. Common practice in some areas producing natural high grade ores is to screen the ore at the mine to about 3/8 in. The oversize is shipped "as is" and constitutes blast furnace feed. The / in. may be shipped to the steel plant where it may be sintered or otherwise agglomerated. At some mines the fines may be pelletizied prior to shipment. With the development of large ocean ore carriers, and with the transportation of slurried concentrates or fines, a trend has developed of constructing large pelletizing plants or other types of agglomeration plants near large consumption centers (i.e., in the Netherlands or Japan) where ores of many types are brought together, ground if necessary, blended, and agglomerated. As an indication of tonnages of agglomerated materials produced, for iron materials alone (the largest share of the total) production in 1970 in the U.S. was Million gross ton Sinter 40.7 Pellets 43.1 Briquettes, nodules, & others 0.1 Total 83.9 During the 1960s, U.S. production of sinter rose from 40.3 million gross tons in 1961 to a high of 48.7 million in 1964, then settled back to almost the 1961 figure in 1970. Pellet production rose steadily from 14.4 million gross tons in 1961 to the 59.9 figure for 1975. Worldwide, sinter production in 1966 was estimated at 340 million mt (mainly in Europe, Russia, Japan, and the U.S.) and pellet produc¬tion the same year at 64 mt (primarily Canada and the U.S.). World pellet production capacity rose to 200 million tons in 1976.

Jan 1, 1985

By Patrizia Pereyra, M. Guzman, C. Toledo, J. A. Rau, A. Ruiz

The use of mining tailings-based geopolymer binder as a substitute for cement can be an interesting alternative to the problem of final disposing of large volumes of them. Indeed, mining tailings have a high silica content, which makes them suitable for geopolymerization. The tailings samples contain Cu, Pb, Zn, As, Sb, Cd and Bi, mainly. X-ray diffraction results show that the tailings are composed of quartz, SiO2 (81%). Geopolymerized tailing samples (GTPS) were obtained by varying the ratio of SiO2/ Al2O3 and SiO2/NaOH. The compressive strength of the GTPS varied between 2 MPa and 8 MPa. The electrical conductivity in the leaching tests varies between 13.91– 16.11 mS/cm2 indicating that ions are present in the solution. However, the pH = 10.5 indicates that acidity is not being generated. The element that mostly leaches is iron. The highest percentage of leaching is observed for cadmium (69%) and chromium (93%). The concentrations of elements are under the maximum permissible limits for water according to the Peruvian legislation. However, mass transfer leach tests and immersion leach tests must be realized.

Feb 1, 2024

By E. D. Gordner

Irrespira ble gutses issuing from the rock fofflb tions ere tJ source of expense ond danger in some metGLl mines. There is a great Variation in the compos i-· tion of such gdses and, os shown 'by recent sampling by the Bureau of ines, the gas rr;;,.y consi$t mostly ct carbon dioxide, (Rocle Strata Gtsses in the Mines of the East Tintic Mining District, by G. E. McElroy, Bu.retau of Mines Serial 2Z75) or f methone (Metruine in Ccalifornia C.old Mines, by B. 0. Picl-Q:lrd i:lnd !.. D. ("iordner, Bure, cf Mines Serial 2303), or nitrogen, sin the present instonce. A nl.liilber of unventilated rt:t.ises in some of the mine of l:l Neva&. district conuin «i'ccumulCltions of l;i hih-nitrogen gas the1t will not supi:ort life or combus­tion. The rdises ore in different geologiecil formations and in widely sep1:1rated. loecslities in the mining district. One ot" two ri::lises in the sme fc.rtr.ation may be full of the gos cand einother nec-r'by be t'ree ot· it. Lives have been lost t:lnd a number of men heave been overcome on enteing unvetilated rtsises in which their­respircable tss hcsd c1ccuni..1.l1::1ted between sldfts. Gener1:1lly, however, the gas see:ns to noozett from the .t'onrbtio:1 ond to ecc1: .. ,i.-1,;.1:.1te so slowly tMt its presence is not suspected t the tfr.1e, bu.t discovered. ed:'t&.c' the raise is t)band.oned. OcCE.isionelly 1 t issues from a ne•.,ly cut cre·tice or fissure under considerca ble pressure and in lar!?e enough '3.'16ntities to overcome or drive 011t men working in unventilated places.

Dec 1, 1922

By Jussi Vaamol

A commercial CFD-code was used to solve isothermal flow fields of gas and liquid in a Peirce-Smith converter. The model was validated with a 1/4 scale water model, and parametric study. Limits of the modeling technique used were recognized, but calculated results indicate that the present model predicts the general flow field with reasonable accuracy. The model was used to examine general flow conditions in an industrial scale PS-converter. Typical scaling factors of physical models were also evaluated with the aid of predicted bubble distribution, patterns of the flow fields and magnitude of flow velocities. The numerical simulations were found to open new viewpoints to the fluid dynamic related phenomena in the PS-process.

Jan 1, 1998

By S. P. Rivers

The stainless steel industry re1ies on nitric-hydrofluoric acid (HNO,/HF) pickling solutions to remove surface contaminants and maintain the corrosion resistance of the steel. More stringent environmental guide1ines are expected to be placed on the disposal of these solutions which could significantly increase processing costs. The U.S. Bureau of Mines has been conducting research to develop a process for recycling depleted pickling solutions, thus reducing the quantity of by product acids generated. Research has shown that F- can be liberated from the predominant iron fluoride species (FeF,') by using oxalic acid in an electrodialysis cell. Ion selective membranes allow dissolved metals in the depleted solution to be replaced with hydronium ions by metathesis, thereby regenerating the HF. The regenerated HN03/HF is then retained in the pick1ing solution. This paper reports on the research effort at the U.S. Bureau of Mines Rolla Research Center to apply electrodialytic recycling to HN03/HF pickling solutions.

Jan 1, 1993

By A. Brown

The swift decline of coal during the period of unprecedented expansion in the Canadian economy is a phenomenon deserving careful examination, because the underlying forces contributing to this decline may have broader implications in our national economy. At the present level of technology, coal is more difficult to process, transport and utilize than liquid and gaseous fuels. Fundamentally, it is a matter of limitation in technique. Because coal is a vast store-house of energy in Canada, the reduction of these limitations is in the long-term national interest.

Jan 1, 1967

By Rómulo Mucho

El Perú ocupa el tercer lugar como uno de los productores más importantes de zinc a nivel mundial y es líder minero en América Latina. En ese sentido, el presente texto describe la importancia de este a través de una revisión de su producción en minas y empresas, la inversión de proyectos, el análisis y consumo de este.

May 1, 2015

By J. Petersen, A. E. Lewis, J. Chivavava

Rare earth elements (REEs) have special properties that prompted their extensive use in high-tech applications. The demand for REE has, therefore, increased over the past years, resulting in the supply risk of the materials. Extraction from non-conventional low-grade ores, like easy-to-mine ion adsorption clays (IACs), by hydrometallurgical methods is being explored to supplement the supply of REEs. The extraction of REEs from low tenor IAC leach solutions requires enrichment using cost-effective methods such as precipitation. Therefore, the aim of this study was to understand the recovery of REEs from IAC leach solutions using various reagents for precipitation. In the first part of the study, recoveries of REEs from IAC leach solutions through direct precipitation using H2C2O4 and NH4HCO3, as well as antisolvent crystallization using C2H5OH, were predicted via thermodynamic modelling using OLI Stream Analyzer. Verification experiments were then conducted through the use of an agitated reactor. Simulation results showed that high yields of REEs were possible using each of the reagents, but large quantities of C2H5OH were required. Experimental results confirmed the high yields predicted from simulations. Precipitation with H2C2O4 was found to selectively recover REEs while rejecting Al. However, utilization of NH4HCO3 and C2H5OH resulted in the co-precipitation of Al. Furthermore, the yield of Y from antisolvent crystallization was significantly lower than the theoretical value. The product recovered from antisolvent crystallization consisted of well faceted, large crystalline particles, which filtered faster than the fine, amorphous REE carbonates recovered using NH4HCO3. REE oxalates were crystalline, larger than the REE carbonates and, overall, showed the highest filtration rate.

Dec 11, 2024

The methods employed for the addition of uranium to steels and cast iron in the Physical Metallurgy Division are outlined. It has been found that the segregation of? uranium is a major problem in aluminum and/or silicon killed steels and that the cooling rate is important in al-lowing the segregate to settle to one area, which can subsequently be discarded. The unsegregated areas were found to be extremely low in total oxygen, acid insoluble aluminum (AizOg) and, in some cases, slightly lower in nitrogen. Uranium recoveries, based on analyses of the unsegregated areas, were quite constant, at about 45 per cent, regardless of the type of uranium master alloy used for the addition. No segregation of carbon, manganese, silicon, sulphur, phosphorous, chromium or copper was observed in these steels. In commercial heats, the recoveries ranged from 7 to? 29 per cent for ladle additions to oxygen converted steel. When the steel was fully deoxidized prior to the uranium addition, recoveries ranged from 49 to 66 per cent, regardless of the steelmaking process.

Jan 1, 1964

By Gillies A. D S

Rail, port and shipping charges represent 30 to 50 per cent of landed costs for Australian coal mines selling to Asia. This proportion is higher for sales to Europe, yet it is in Europe where Australian producers are aiming for increased market share. The landed cost of coal to the international customer is the key parameter which determines market competitiveness. The objective of this study is to examine Australian export coal competitiveness in terms of transport distance. The approach used examines world coking coal and steaming coal production and the transport distances between major exporting regions and importing countries. Reference is made to the importance of land transport costs and a comparative approach for emphasising the relative magnitude of this factor is developed. Models developed are examined in terms of Australia's exports and a conclusion is reached that a reduction in rail freight costs would be an effective measure for improving the competitiveness of Australia's coal industry.

Jan 1, 1994

By R. W. Smith. Discussion by D. Watson, R. M. Manser

D. Wotson, R. M. Monser (Watten Spring Laboratory, Stevenage, Herts., U. K.) - This is a valuable and interesting paper and will make an important contribution to the development of a general theory of silicate flotation. In particular the dominance of surface reactions which produce fluosilicic acid and its ions has been convincingly demonstrated. In a paper to be published shortly, however, we offer some evidence which is not consistent with the feldspar activation theory proposed by Prof. Smith. This theory, given in Eqs. 17-20, suggests that activation takes place through the exchange of SiF6 ions for OH- at aluminum sites. This results in a negatively charged site facilitating adsorption of RNH3 Firstly, we have determined the flotation response (using the vacuum flotation technique) and the adsorption of dodecylamine on a natural feldspar (albite) and on the same feldspar after washing with perchloric acid at pH3. This pre-treatment was shown to remove surface adjacent aluminum atoms. It was found that although the acid washed feldspar floated much less easily than the untreated sample, the function of fluoride ion - giving activation over the pH range 4-6.5-was preserved. Moreover, the amount of dodecylamine adsorbed either with or without fluoride present is little affected by acid-washing, despite the depression caused by this treatment. This suggests that surface aluminum atoms can be of little importance in the fluoride activation mechanism. Secondly, we have determined the changes in solution concentration of F- and H+ (or OH-) accompanying reaction of the surface with fluoride ion. The ratio of H+ lost from solution to F- lost is high, ranging from 6.9 at pH4 to 1.0 at pH 7.5. This is consistent with reaction of HF (6 molecules for every Si removed) at the surface, producing SiFi-ions, but not with the re-adsorption of these ions.

Jan 1, 1967

By John J. Collins

The plight of the Japanese mining business is pitiful. Coal mines were given the highest priority for all materials they needed, yet between the end of the war and June 1948, the government was obliged to subsidize them to the extent of 22 billion yen, this being the difference between the consumer's price and the producer's price. Most of the metal mining companies have been operating at only one fifth to one third of war-time production rates, and financial losses have been terrific. The chief difficulties have been a plethora of office workers and a dearth of equipment, supplies, and miners. The principal material needs at metal mines are steel rails. cars, plates, nails, rubber hoses, and belting, to say nothing of modern core drills which are totally lacking. Until recently the great shortage was in coal; for lack of fuel the smelters and factories failed to produce the very metals and equipment now needed to operate the mines. Nation-wide shortages have created a monstrous inflation of prices throughout all the economy, currently amounting to 200 times the prewar figures. For example, the price of copper ranged from 500 to 900 yen per metric ton for many years until 1937, but in mid-1948 producers were

Jan 1, 1949

By P. G. Winchell, J. K. Jackson

The strtcture of body-centered Fe-Ni-C alloys (0 to 16.5 wt pct Ni) containing less than 0.015 wt pct C was investigated by measuring the carbon-diffusion peak at low frequencies with a torsion pendulurrr. By determining the Snoek damping in ferrite and in quenched alloys of identical composition, the effects of nickel content and heat treatment were separated, and the existence of a structure in which Snoek damping is greatly reduced was revealed in the quenched ternary alloys. The relative amount of this structure increases with increased nickel content and cooling rate. It is proposed that this structure may be highly imperfect or tetragonal. In Fe-Ni-C alloys containing only ferrite the addition of nickel (0 to 5.1 wt pet) decreases tke area of the carbon-diffusion peak and shifts its position to lower temperatures but broadens the peak only slightljl. The decrease in peak area with increasing nickel implies that short-range interactions with the nickel atoms prevent some of the carbon atoms from participating in the relaxation process. The shift in the peak position indicates a long-range effect of nickel on the movement of carbon atoms so that at 300°K the diffisivity of carbon in -ferrite is increased by about 35 pct by the addition of 5.1 tut pct Ni. The results are presented as distributions of relaxation strength 072 the activation energy under the assumption that the frequency factor is invariant. BODY-CENTERED iron-base solid solutions dissolve carbon interstitially in the octahedral sites. The occupation of an octahedral site produces a tetragonal distortion of the surrounding lattice. These sites fall into three sets according to the orientation of the tegragonal distortion associated with each and may be identified by their lattice coordinates as: type 1/2 0 0, type 0 1/2 0, type 0 0 1/2. At low carbon levels in cubic ferrite the carbon atoms are distributed at random1 among these sites. In high-carbon body-centered iron-base solid solutions, which are unstable with respect to several two-phase mixtures, a tetragonal structure occurs as the product of the diffusionless transformation of austenite. This transformation is commonly accompanied by appreciable microstrain and its product is called martensite. The tetragonality of martensite, a supersaturated solution of carbon in a iron, is maintained prior to decomposition even though local diffusion of carbon occurs as evidenced by carbide precipitation. The tetragonality is taken as evidence that one set of octahedral sites is preferentially occupied by carbon. (This preferential occupation is called ordering below.) Support for this view is presented by the absence of strain-induced carbon-atom diffusion in high-carbon solid solutions (martensite). Such diffusion occurs in ferrite and produces the 40°C internal-friction peak observed at 1 cps frequencies.' Thus, there appears to be qualitative evidence favoring the view that at sufficiently high carbon levels tetragonality arises spontaneously as a result of the ordering of the carbon atoms; however, no experimental evidence exists concerning an equilibrium between cubic and tetragonal body-centered solid solutions. Moreover, attempts to estimate the energy of ordering7-' predict a value too low to maintain the tetragonality observed at medium carbon levels, 0.3 to 0.6 wt pct C. In the present work an attempt using internal-friction measurements is made to establish the presence or absence of tetragonality in low-carbon body-centered solid solutions formed by quenching austenite. Fe-Ni alloys containing about 0.01 wt pct and 0 to 15 wt pct Ni were selected for the study. While the work was in progress Gilbert and Owen10 reported that the transformation which occurs in these alloys during quenching at rates up to 5000°C per sec is not martensitic but is more properly categorized as massive. Thus, the solid solution

Jan 1, 1964

By Colin J. Dixon

The full realization of the potential of computers in geological in- formation system demands new approaches to the machine representation of information. At the same time, the feasibility of such a system, particularly in commercial field, demands greater freedom in input preparation and a degree of standardization in the arrangement of subject matter system. The paper describes some of the basic notions of project "GEOSEMANTICA 70". The aim of the project is to devise means of storing real geological informations in a machine rather than the representation of the information in human language form. This is seen as the only long-term solution to the problems of the complex vocabulary of geology and the complex syntax of geological description. Effectively, a machine language is being defined, consisting of a set of symbols and a date structure for representation of geological and related information. Beyond this, is the definition of a set of rules allowing the use of constrained text as an input/output medium. The investigation is oriented primarily to the representation and handling of information about mineral deposits and the associated geographic, economic and engineering information.

Jan 1, 1969

By A. A. Compoli

Injecting water under pressure to wet the coalbed in advance of mining reduces mining-generated respirable dust. Owing to economic and geological barriers, water infusion for longwall dust control in the United States is currently limited to the Pocahontas No.3 Coalbed in Virginia. Water is pumped into the coalbed through underground boreholes drilled horizontally from the headgate toward the tailgate side of retreat longwall panels. This paper theorizes that the barriers to widespread utilization of water infusion for longwall dust control could be overcome by long-duration, low-pressure water infusion through vertical gob gas boreholes. Currently, 43% of the 72longwall mines in the United States employ vertical gob gas boreholes. Computer coalbed reservoir simulation suggests that one vertical surface borehole could infuse the same longwall panel area as four horizontal boreholes in the current water infusion system for longwall dust control in the Pocahontas No.3 Coalbed.

Jan 1, 1995

Nearly as impressive as the machines that will be on display at MINExpo are the massive engines and tires that keep the machines moving. As you can imagine, it takes a special tire and special engine to run these machines. The following is a look at some of the exhibitors that will be at MINExpo displaying engines and tires. Cummins Inc. Cummins Inc. will display a lineup engines from 37kW to 2,983 kW (49 hp to 4000 hp) at MINExpo, representing the most extensive ?smallest to largest? range the company has ever put on display.

Jan 1, 2012

By Héctor Benavente V

La presente investigación señala el comportamiento de la cinética de flotación para los sulfuros de cobre y molibdeno en las condiciones de operación de la concentradora de Toquepala. Para ello, se consideran dos variables: tamaño de las partículas y el tipo de colector utilizado. Una vez obtenidas las variables, se optimiza la recuperacíón de los sulfuros en los rangos granulométricos que lo requieran.

Aug 26, 1988

By George L. Richert

The Minas de Matahambre is situated on the north coast of Cuba, in the Province of Pinar del Rio, approximately 150 miles west of Havana. This nine is the only producer of copper in Cuba, and has been worked for the past 15 years. In 1921 the property was affiliated with The American Metal Co., Ltd., and has been worked by them since that time under the direction of Mr. D. D. Homer, General Manager. Extracts from P. D. Wilson's ?Preliminary report on the geology at Minas de Matahambre? have been freely used in this report.

Jan 1, 1929