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By Michel R. Julien, Michel Lemieux, Jean Cayouette, Daniel Talbot

"The Louvicourt Mine located near Val d’Or, Quebec has been in operation since 1994. It produces copper and zinc concentrates. The tailings generated from the ore processing operations have a strong net acid generating potential. Louvicourt Mine, a grass root project, was designed for closure with the best available technology at the time of design. In order to inhibit short and long time acid potential generation, sub-aqueous disposal was selected at the design stage. Given the fact that disposal in a natural lake was ruled out up front for obvious reasons related to loss of natural habitat and risks of permitting delays, a man made facility built with dams was planned. This mine includes therefore the first fully man-made sub-aqueous tailings disposal facility built in Canada. The requirement of using sub-aqueous disposal had serious implications on the placement of tailings. This tailings facility located about 9 km from the mine site has been selected based on the available natural confinement, the favorable foundation and hydrogeological conditions. This paper describes the site and the design criteria that were used. A presentation is also made on the placement technique to maximize storage and its impact on the operation of the basin. The performance of the basin, the dams and the decant structures is reviewed.Résumé : La mine Louvicourt, située près de Val d’Or, Québec est opérationnelle depuis 1994. Elle produit des concentrés de cuivre et de zinc. Les résidus générés par les opérations de traitement du minerai possèdent un fort potentiel net de génération d’acide. Le parc à résidus de la mine Louvicourt, implanté dans un milieu naturel intact, fut doté dès sa conception initiale de la meilleure technologie de fermeture disponible à l’époque, soit la déposition sous couverture aqueuse et ce, dans le but de bloquer le potentiel de génération d’acide à court et à long terme des résidus. Etant donné que la déposition dans un lac naturel fut mise de côté dès le départ pour des raisons évidentes reliées à la perte d’habitats naturels et au risque d’introduire des délais dans l’émission des permis, un étang artificiel délimité par des digues a été conçu. Cette mine fut donc la première au Canada à être dotée d’une installation anthropique de disposition des résidus sous une pleine couverture aqueuse. L’exigence d’une déposition sous couverture aqueuse a eu des implications sur le mode de mise en place des résidus. L’emplacement de l’installation de gestion des résidus a été choisi en un lieu situé à environ 9 km du concentrateur sur la base du confinement naturel disponible et des conditions hydrogéologiques et géotechniques favorables. Cet article décrit le site et les critères de conception utilisés. Une présentation est faite sur la technique de mise en place utilisée pour maximiser l’entreposage et son impact sur l’opération du bassin. La performance du bassin, des digues et des structures de décantation est également revue."

Jan 1, 2004

By B. P. Spigarelli

To meet the growing need for CO2 capture and storage technology, Michigan Technological University is researching CO2 capture and storage using carbonate solutions. The objective of the present study was to increase the absorption rate of CO2 into the carbonate solution without reducing the absorption capacity of the solution. This approach used a polypropylene glycol methyl ether (PPGME) as a surfactant to chemically alter the gas bubble size. Experiments were conducted to study the absorption rate of CO2 at varying surfactant concentrations of 0, 0.12, 0.24, 0.36, and 0.48 g/L. Results showed that as the concentration of surfactant increased in solution, the absorption rate also increased. The CO2 absorption rate increased from 3.45 mmol/min CO2 at 0g/L PPGME to 3.92 mmol/min CO2 at 0.48 g/L PPGME. This amounted to a 14% increase in the CO2 absorption rate with no decrease in absorption capacity of the solution.

Feb 27, 2013

"The Murray Plant of the American Smelting & Refining Company is situated seven miles south of Salt Lake City, and has a fine view of the Salt Lake Valley with its fertile farms and orchards.It is located on the Los Angeles & Salt Lake and Denver & Rio Grande Western Railroads, and has a fine electric car service, cars running every 15 minutes.The beautiful and majestic Wasatch Range lies about five miles to the east and the Oquirrh Range to the west, and from these mountains a large proportion of the ores treated are obtained.The location is very central, ores coming to the plant from all directions. Park City, where a large tonnage of high grade silver-lead ore is obtained, lies to the east and the camp of Alta is just across the mountains from Murray.To the west is the wonderful camp of Bingham, which produces a large tonnage of lead ores, in addition to its immense tonnages of copper ores, which are treated at Garfield.Tintic, to the south, sends in quantites of dry silicious ores, as well as silver-lead ores.Besides the above, ores are shipped to the plant from Stockton, Ophir, Milford and other camps in Utah, as well as from Nevada and Idaho, and also some ores from Cali¬fornia, Oregon, Washington, Wyoming and Colorado.The American Smelting & Refining Company took possession in 1899 of its Utah properties which consisted of the following plants, all of which have been dismantled:"

Jan 1, 1925

By R. P. King

Flotation plant simulation, a relatively recent methodology in mineral processing, is defined and corresponding uses are discussed. Typical simulation structures are compared. Current problem areas exist although these are not insurmountable. Following a brief state of the art discussion, the N. I. M. simulation program is reviewed. In general, digital plant simulation is expected to be of substantial benefit in the near future.

Jan 1, 1976

By Xubo Chen, Zhiqiang Hu, Zhijian Sun, Gaoyun Zhou

"The research aimed at developing an efficient and environmental frother,which was applied in the flotation of sulfide ores. The flotation properties of an efficient frother and pine oil have been studied relatively by flotation tests of lead and zinc sulfide ores. At the same time, the biodegradability of two kinds of frother has been studied by the method of biological respiratory curve. The test results show that the flotation properties of new frother are superior to pine oil such as flotation rate, dosage etc. and its biodegradability is superior to pine oil. INTRODUCTION Frother is a kind of important agent in flotation reagents.In practice, the criterion of the foaming performance of the frother is what is high and low according to flotation indexes. The difference of different minerals and flotation technologies has great influence on the foaming performance of frother, and it is very important to choose the corresponding frother. The type, dosage and selectivity of frother in flotation process must be considered carefully. In today's society, environmental protection and ecological protection are becoming more and more important, and the environmental and ecological damage from mine development has aroused increasingly more attention. The use of mine agents has promoted the development of mineral resources, greatly improves the recovering utilization of mineral resources, at the same time, the production and use of mine reagents also inevitably bring about pollution, and result some influence or damage in the ecological environment.The frother is a common kind of reagent in the flotation process of the concentrator. In many cases, the waste water in the concentrator can not be let out in the natural water because the higher content of the frother in the waste water results in higher index of COD.This will inevitably increase the cost of waste water treatment in the mine.Therefore, the choice of frother should not only consider its influence on the flotation index, but also consider its influence on environmental protection. Waste water treatment is a way to solve the waste water pollution, but it needs to cost a lot of fund, manpower and material resources.And the development of high efficiency pollution-free reagent is a good way to reduce the production cost of mining enterprises and reduce the environmental pollution."

Jan 1, 2018

By M. C. Williams

As the flaws in the population balance model (PBM) comminution model are examined more deeply, further errors and problems were discovered. The Levenberg-Marquardt algorithm for systems of constrained non-linear equations was used to solve the dynamic PBM grinding equations to obtain the grinding selection and breakage rate functions. The fact that the PBM model equation Inverse Problem is degenerate or underspecified is demonstrated. Multiple solutions to the same PBM equations are provided. It is shown that there is no unique solution to the Inverse Problem unless additional constraints are provided or assumptions are made such as the Arbiter-Bhrany normalization assumption. The severity of the non-uniqueness problem for dynamic grinding is demonstrated. Each solution to a dynamic PBM, while giving the same prediction for a given grinding time interval, gives different solutions or predictions for mill composition for other grinding times. Actual experimental grinding data was assessed to determine the functionality of mill selection and breakage functions.

Jan 1, 1993

The Reefton Goldfield on the West Coast of the South Island of New Zealand was a significant gold producing area between 1860 and 1951. During this period it produced approximately 2.1 million ounces (67 tonnes) of gold. The largest single producer on the goldfield and the deepest mine in New Zealand, was the Blackwater Mine at Waiuta which produced 21 tonnes of gold. The Prolubition Shaft reached a depth of 878 metres (317 metres below sea level). The mine closed suddenly in 1951 with about 66 000 tonnes of are remaining in the stapes. Since closure there has been no attempt to determine the ore potential of the mine at depth. This paper summarises the geology, history and resource potential of the mine and sets out two options for evaluating the remaining resource. The options are either deep drilling from surface or recovery of the Prohibition Shaft and underground development and drilling. A schedule for each option is presented and discussed.

Jan 1, 1992

THE International First-Aid and Mine-Rescue con-test, under the auspices of the U. S. Bureau of Mines, was held at Butte, Mont., on Aug. 20, 21 and 22. As usual, the first-aid elimination contests were held the first day, the finals the second, and the mine-rescue contest the third. While the number of teams entered was not as great as at some previous contests held nearer the coal-mining districts of the East, the atten-dance was much larger than usual, due to the great interest in first aid, rescue work, and accident preven-tion that has been created by the effective support and constructive policy of the Anaconda Copper Mining Co. toward them. The winner of the first-aid contest was the Great Falls Zinc Mill team of the Anaconda company, of which Fred Erickson is captain. Second place went to the Baton Rouge team of the Standard Oil Co. of Louisi-ana, and third to the Great Falls Furnace Refinery team of the Anaconda company.

Jan 9, 1928

By Murray W. Hitzman

Two great revolutions in mining occurred during the 20th century. The first took place almost 100 years ago (1903-1905) with Daniel Jackling’s experiment in the economies of scale for large-scale mining at Bingham Canyon. Jackling’s ideas changed the focus of base metal exploration toward lower-grade, high-tonnage deposits. The second revolution was the impact of environmental and social concerns on mining. It started near the end of the 20th century and is still under way. This article speculates on the effects of this second revolution on the future of mineral exploration.

Jan 1, 2005

A large scale distributed process con-trol system has been successfully applied to the automatic control of aluminium reduction cells at Boyne Smelters. A three stage hierarchy of minicomputers and microcomputers is used to continuously monitor and control conditions in each cell and to manage the data generated during the process.The automation hardware was purchased on the basis of low cost, high reliability, prior use in the aluminium industry and a high level of backup under failure conditions. The hardware has met performance criteria to date.The process control strategies have continually been updated to minimise the energy and raw material consumptions in each cell. A major change to systems software has recently been made to decrease the development time for-future changes. Various low energy potline retrofit alterations are currently being investigated requiring significant changes to the process control strategies.

Jan 1, 1985

By Connor J. W

Nifty Copper Operations was established to treat a copper orebody situated in the East Pilbara area of North West WA, located approximately 70 km west of Telfer in the Great Sandy Desert. The plant was designed to treat the oxidised portion of the orebody with underground development following at a later date. Nifty was designed to produce 16 500 tpa of copper cathode. This will increase with treatment of the chalcopyrite ore (underground resource). Ore processing is similar to other operations of this type but has its unique challenges. Problems discussed are: fine clay minerals which hinder percolation; oxidation of organic by manganese in the electrolyte; crud formation by clays; third phase emulsions; and organic carryover into the electrowinning tankhouse. As the orebody utilisation progresses, some sulphide material will require leaching and further investigations into liquor chemistry.

Jan 1, 1996

By B. C. Blakey

Unlike most hydrometallurgical slurries, those containing significant concentrations of goethite are typically highly viscous and shear-thinning, even at solid volume fractions below 5%. The viscosity may also depend upon time. These characteristics must be taken into consideration in slurry transport and heating. The technical literature is replete with apparent contradictions regarding the viscous behavior of these slurries, which may be due, in part, to variations in viscosity-measuring techniques. We present techniques that yield consistent results suitable for use in process design. A striking degree of time-dependent behavior is demonstrated for a laterite slurry. Reliable methods to design and analyze tubular transport and heating systems for time-independent slurries are summarized. Rules of thumb are then offered to account for the effects of time-dependency.

Jan 1, 2000

Ecuador a gross domestic product (GDP) grew 8% despite a slowdown in production and sales of petroleum, the dominant economic sector. Crude petroleum exports, which amounted to about 35% of total exports in 1977, were valued et $484 million,2 a decrease of 14% from 1976 values. Petroleum export sales were depressed because foreign buyers were somewhat uncertain that State-owned Corporación Estatal Petrólera Ecuatoriana (CEPE) held legal title to the oil until final settlement with Ecuadorian Gulf Oil Corp. In addition to the legal complication, Ecuador maintained a relatively high export price for oil until late in the year. There was also a shrinkage of traditional U.S, markets owing to the Alaskan pipeline becoming operational and an increased availability of Mexican supplies. The export market was also affected by increased domestic production in Peru and Chile, which lessened their import needs, and the pressure of greater competition from the Middle East in supplying crude oil to Caribbean refineries. About 20.4 million barrels or 40% of Ecuador's total crude exports went to the United States. Only 27 wells were drilled in Ecuador during L977; of these, 16 produced oil, 3 were dry holes, and 8 were suspended. About 31 wells were planned for 1978. Three new oilfields were discovered during 1977; two by CEPE in northeastern Ecuador and one by the Argentine State oil company Yacimientos Petraliferos Fiscales (YPF), operating in Ecuador under a service contract. CEPE's two discoveries tested at 5,000 and 1.450 barrels per day, respectively. The YPF discovery tested at about 1,000 barrels per day. Ecuador altered its position regarding

Jan 1, 1981

By Susanne Hahn

The Siemens VAI software model DynaPhase calculates thermodynamic properties depending on the chemical analysis of steel. It can be used online together with Siemens VAI’s secondary cooling model SIMETAL Dynacs 3D which is a unique feature. Offline it can be used to investigate the thermodynamic properties of steel grades and therefore supports the development of new grades. The core of DynaPhase is a substitutional solution model for the Gibbs free energy to calculate multi-component phase diagrams. The parameters of this model are determined by employing the CALPHAD approach. This model is combined with a microsegregation model to account for the interdendritic solidification process. New DSC (differential scanning calometry) measurements of the department of metallurgy of the Mining University of Leoben have been used to improve the DynaPhase database for high Al or Si concentrations. By comparing this experimental data to calculations it has been found that some of the widely used commercial software tools do not describe the ternary system FeAlC for high aluminum concentration correctly. In this paper we will show how thermal properties of high Al grades change with the optimized database and what impact this has on the secondary cooling of continuous casting, e.g. how the solidus point shifts on the strand. Moreover we will show that the online use of DynaPhase has many advantages for the production. Since DynaPhase uses the actual chemical analysis of the steel grade and not just concentration ranges or averaged concentrations it is possible to optimize the cooling strategy during casting for the actual chemical analysis of the actual heat.

Jul 30, 2018

By E. E. Malouf

Rapid depletion of the world's mineral deposits combined with the expanding demand for metals places great pressure on our ability to provide technologically and economically feasible processes to recover greater amounts of metals from progressively lower grade sources. Chemical mining is one area in which expanding research and development can provide new processes or refinements to existing ones. These new techniques could result in increased production of metals from materials now considered uneconomic to process by current technology. To mine by chemicals requires the interaction of such disciplines as hydrometallurgy, microbiology, chemistry (both organic and inorganic), fluid flow, mineralogy, geology, and of course, economics. One of the least understood areas but one which may end up being an essential part of any chemical mining process is microbiology, i.e., the role of microorganisms in altering minerals and metals in solution.

Jan 1, 1971

By Robert E. McIvor

"“Classification System Efficiency (CSE)” is a powerful, emerging tool that can be used to increase grinding circuit efficiency. It is defined as the percentage of the ball mill energy being used to grind target, oversize particles. The discovery, validation and current use of CSE, including how it was manipulated, are described through seven plant case studies. These resulted in efficiency improvements ranging from 3 to 30 percent, along with major reductions in over-grinding. The achievable CSE for any given circuit is described. This paper demonstrates both how, and how much, every plant can benefit from increasing grinding circuit CSE.DEFINITIONS: BALL MILL CIRCUIT “CLASSIFICATION SYSTEM EFFICIENCY (CSE)”, “EFFECTIVE MILL GRINDING POWER”: “WASTED/OVER-GRINDING MILL POWER”The closed ball mill circuit is shown in Figure 1. The extreme importance of the circulating load ratio in determining circuit productivity was demonstrated by Davis (1925) and re-published by Guadin (1939), as shown in Figure 2. The circuit production rate increases with increased circulating load ratio, rapidly so at first and continuing to increase more gradually with higher and higher values of circulating load ratio.The underlying cause of this relationship was seen when comparing the ball mill feed and product size distributions from two different ball mill circuits, one with a low circulating load ratio, and one with a high circulating load ratio (Figure 3). While the F80’s and P80’s of these two circuits were close to the same, the mill feed and discharge size distributions were quite different. The ball mill in the circuit with the higher circulating load ratio contained a substantially greater fraction of material coarser than the target P80, as indicated by the respective mill feed and discharge size distributions. This fraction represents the fraction of the mill power being expended on “coarse” (in this case, plus P80 size) material, or the circuit “classification system efficiency.” The “effective mill grinding power” is the total mill power multiplied by the CSE. The compliment of CSE, the remaining fraction of “fines” in the mill, is the fraction of the mill power being wasted, and spent on over-grinding of material already finer than the circuit target product size. This is the “wasted/over-grinding mill power”"

Jan 1, 2013

By W. H. Moore

It seems necessary, at times, that we should reconsider some of the more obscure causes that lead to explosions of gas and coal-dust in mines, in the hope that a recapitulation will keep before us that old and true saying "eternal vigilance is the price of safety". This explosion, while not extensive (resulting in only two much to be regretted deaths) enlarged our vision as to the possibility and probability of other explosions with more disastrous results. As this is only a partial report I shall have to omit many things that are generally included in describing a mine explosion. The mine was worked exclusively with electric cap-lamps -only firebosses and other officials carried safety-lamps. All shots were examined and fired by firebosses with a small hand-battery. Monobel was used exclusively for blasting, and clay for tamping. The system of haulage iri use was main-rope and winches, horses being employed for gathering. Compressed-air was the motive power for all winches and pumps, excepting the pumps at the shaft-bottom which were steam-driven. The mine was wet with practically no dust anywhere, except what was being made at the coal-face in the getting of the coal. Gas was found occasionally, generally in the brushing, especially where the brushing was carried up to a small seam, 2 to 6 feet above the main seam. The place where the explosion took place was known as Leigh's heading, which was being driven to the rise, immediately inbye of the siding (off No. 1 left, off the new slope) and was about 90 feet up from the level.

Jan 1, 1926

In October, the Aluminum Company of America restarted the fourth of seven pot-lines at its Point Comfort, Tex. primary aluminum smelter. The price of primary aluminum ingot, as quoted by American Metal Market, was increased from a range of 60.5 to 63.0 cents per pound at the end of September to a range of 66.0 to 66.5 cents per pound at the end of October. BERYLLIUM On October 15, Brush Wellman, Inc., of Cleveland, one of two U.S. producers of primary beryllium products, announced a planned $6 million expansion of its extraction plant at Delta, Utah, increasing the plant?s capacity to extract beryllium from bertrandite ore by 25%. Another $5 million will be spent on two mine expansion programs in Jaub and Millard Counties, Utah. Other mineral claims and 1 eases he 1 d by The Anaconda Company will be taken over by Brush Wellman through lease or purchase. This expansion, when completed in 1981, will decrease U.S. dependence on imported beryl ore.

Jan 1, 1979

llmenite from the west coast of the South Island, New Zealand, shows exceptional reactivity with dilute sulphuric acid. Based on this, a cyclic acid leaching process was developed for the production of material with more than 98% TiO2, suitable as a substitute for mineral rutile.Titanium hydrate is recovered from the leach liquor by hydrolysis, and is calcined to give the required product.Ferrous sulphate is crystallized from the hydrolysis filtrates, which after concentration are returned to the leaching stage. The need for further evaluation of the process on a larger scale is indicated.

Jan 1, 1973

By M. Gangal, M. Grenier, D. Mchaina, S. Hardcastle

"Exposure to airborne respirable silica in surface and underground mine operations is known to be the cause of industrial lung diseases. For this reason, silica is a regulated substance and worker exposure must be monitored regularly. Diesel exhaust also contains substances which are potential caricinogens. In an underground setting, diesel particulate may be the main component of what is referred to as respirable combustible dust (ReD). Although diesel particulate or soot is not at present a rigorously regulated substance, new epidemiological data is prompting North American institutes and agencies to regulate diesel soot or RCD exposure. This paper describes a method where by silicaand RCD exposure may be determined using a single personal sample. In this method, an airborne respirable dust sample is obtained and analyzed nondestructively for silica components using an on-filter X-ray diffraction method. Filters are then ashed at 500°C in a muffle furnace over a four-hour period to determine mass loss due to RCD burning. Using on-filter X-ray diffraction analysis as opposed to redeposition of dust samples onto another analytical substrate allows the"

Jan 1, 1992