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By I. E. Puddington, F. W. Meadus

The beneficiation of barite in mill tailings using an agglomeration technique has been demonstrated. Barite was selectively absorbed from a conditioned aqueous slurry into a collector oil by mechanically mixing slurry and oil. The resulting oil-bonded barite-containing agglomerate was washed, to remove gangue material, and further mechanically contacted with dilute H2SO4 This treatment resulted in the transfer of barite into the aqueous phase. Grades as high as '97% BaSO4, with recoveries of 80%, have been obtained using this technique.

Jan 1, 1973

By S. M. C. Santos

Preliminary bench-scale studies were carried out on the leaching of a zinc sulphide concentrate from Somincor, Portugal, and the purification of the resulting pregnant solution using solvent extraction techniques. The sulphide concentrate contained 36% Zn, 36% S, 2% Fe and 4% Cu. The leaching was carried out with sulphuric acid in the presence of ferric sulphate as the oxidant. Important leaching parameters, such as the effect of reaction time, the solid-liquid ratio, temperature and concentrations of acid and oxidant, were investigated. After leaching, the recovered solution was contacted with an organic phase containing Acorga 5640 to remove the copper. Subsequently, the removal of iron from the leaching solution was achieved with a mixture of Cyanex 272 and TBP. This solvent mixture was relatively selective for iron over zinc. The stripping of the loaded solvent was performed with 200 g/L H2SO4. Six countercurrent extraction stages achieved a separation of about 99% of the iron from the leaching solution. The iron-free leachate can be further treated to recover minor metals by cementation, and finally, zinc by liquid-liquid extraction. The advantages of the suggested process relative to the traditional jarosite process are discussed.

Jan 1, 2006

By W. Zieman

"The low consumption of reagents can probably be attributed to a good clean type of ore. The cyanide level is kept at 0. 8 lb/ ton of solution and the lime at 1. 8 to 1.9 lb per ton of solution (pH 12. 2 to 12 .3). Experience in cutting down the lime level in half produced troubles in the presses, in the refinery and resulted in higher cyanide consumption. Finally the residue increased under these conditions, High lime always seems to prevent the trouble from occurring.A survey at one mine of the taxable work, performed in the mine shops for use in the mine, showed that under the new regulations, this had increased some 30 times what it was before the new rules came into effect on June 14, 1963.A water softener idea is incorporated at Lamaque with the crude addition of 100 lb of lime per shift to a spare agitator to precipitate the bicarbonates as carbonates from the water before it enters the mill. The lime titration of the softened water is about 0,2 to 0.3 lb per ton of solution (pH 11). This water is used mainly on the filters as washes."

Jan 1, 1964

By Douglas R. Schmitt

In general, knowledge of the state of stress within the Antarctic lithosphere remains largely unconstrained due in part to Antarctica?s inaccessibility and because of the paucity of seismic focal mechanism solutions. As such, an important component of the ANDRILL project was to acquire new information on the stress directions and magnitudes within the upper crust. Extensive fracture mapping of the core and oriented ultrasonic televiewer logging were carried out to provide strong constraints on both stress orientations and the faulting regime. The first hydraulic fracturing stress determinations in Antarctica were also carried out to provide complimentary stress magnitudes. These measurements were accomplished using a wire-line transported hydraulic fracturing system consisting, essentially, of two synthetic polymer packers that were inflated to isolate the 1-m long pressurization interval. The tests were conducted at the end of the drilling and logging in a ~130-m section specially drilled below 1000 mbsf (nearly 1500 m from the rig floor) for hydraulic fractures. This zone was drilled primarily through competent, dense, and low permeability diamicts. The core fracture and televiewer logging information was used to site twenty separate measurements. Classic hydraulic fracturing pressurization records with unambiguous breakdown and fracture closure pressures were obtained in about half of the measurements. The remaining tests provided fracture propagation and closure pressures that are consistent with the classic breakdown curves, but they did not include a clear breakdown pressure and are indicative of the reopening of either natural or drilling induced fractures in the wellbore wall. The preliminary analysis of the results are in generally good agreement with the stress directions indicated by the core fracture logging and the stress regime suggested by the character of the drilling induced core fractures.

Jun 1, 2012

By H. C. Cooke

"This paper has reference in a general way to the region extending from the north shore of lake Buron to the northern limit of the elliptical-shaped area generally known as the Sudbury Basin, and more especially to the district lying south of the Basin (Fig. 3). Attention is concentrated mainly on the structure of the district and, as space does not permit of much geological description, it is assumed that the reader has some knowledge of the general geology. The accompanying table outlines the sequence of the rock formations according to the most recent available information; for further details the interested reader may consult the publications of the various authors mentioned in the paper.STRUCTURE OF THE SEDIMENTARY ROCKS SOUTH OF THE SUDBURY IRRUPTIVEThe rocks south of the Sudbury irruptive, excluding certain intrusives, are, in order from north to south:(1) A band of basic lavas.(2) A band of well-bedded greywackes and quartzites, long termed the McKim greywacke.(3) The Copper Cliff formation, with McKim greywacke' both to the north and south.(4) The Ramsay Lake conglomerate.(5) A thick quartzite formation.All these rocks strike approximately east-northeast, dip steeply south, and generally face south, though there are local exceptions."

Jan 1, 1954

By H. A. Steane

THIS BRIEF PAPER presents the information available on the use of Dorrclon?is in the middling re-grind unit at the lead-zinc mill of Canadian Exploration Limited. The plant throughput is 1,650 tons per twenty-four hours. The flotation feed is ground to 60 per ?Cent passing through 200 mesh. It contains some composite 11articles of sphalerite in calcite, and these reported either in the final zinc concentrate, thus lowering the grade, or in the tailing, with loss of zinc. The re-grind unit was set up in the zinc flotation circuit to liberate the sphalerite from these middling particles, to raise the grade of concentrate and improve recovery. Grinding through 325 mesh should give substantial liberation of locked sphalerite. The middling regrind unit consists of two Dorrdones and one ballmill arranged as shown in the -accompanying flow-sheet. The Hardinge ball-mill, size 7 ft. x 36 in., was free for this use as a result of recent plant expansion. The two Dorrclones were purchased, and the necessary pumps and pipe lines were installed to complete the regrind unit. The unit has been developed over a period of two years by several steps and various flow schemes until reaching tl1e present flow scheme. These steps are not elaborated here, because the changes were made to determine the best product to work on for flotation metallurgy, and not because of the Domrolone classifying ability.

Jan 1, 1956

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 W. J. Jenner

"Introduction The Saskatchewan Power Corporation is a provincial crown corporation which operates under a mandate to supply all customers within Saskatchewan with electricity and natural gas. The Saskatchewan Power Corporation operates two coal mines within the province of Saskatchewan. The Souris Valley Mine is located a few miles south of the city of Estevan and produces approximately 300 000 Mg of lignite per year. The lignite is shipped about four kilometres by truck and burned at the 882 MW Boundary Dam Power Station, also owned by the Saskatchewan Power Corporation. The Poplar River Mine is located just south-west of the town of Coronach, Saskatchewan which is some 190 kilo metres west of Estevan. This mine produces approximately 1 675 000 Mg of lignite per year. The lignite is shipped seven miles by rail to the Saskatchewan Power Corporation's Poplar River Power Station. The Poplar River Mine is the sole sup plier of fuel to the Poplar River Power Station, which generates some 300 MW of electrical power. A second 300 MW unit is due to be commissioned at the Poplar River Power Station in mid-1983 and the Poplar River Mine will have doubled its capacity to approximately 3 350 000 Mg per year by that time: Souris Valley Mine Geology The Souris Valley Mine extracts lignite from the Estevan seam of the Ravenscrag Formation. This formation is of Tertiary age and was deposited during the Paleocene Epoch. The Ravenscrag Formation outcrops throughout southern Saskatachewan and all coal mined in the province occurs in this formation. Ravenscrag sediments are deltaic in origin and are composed of a series of fine sands, silts, clay and lignite deposits."

Jan 1, 1985

By S. Torizuka, I. Mizushima. Kawasakitohri, A. Ohmori, K. Nagai

Strain (work)-hardening in tensile tests were examined for low carbon steels with various ferrite grain sizes ranged from 0.4µm to 16µm. The steels had microstructures composed of ferrite grains and dispersed cementite particles. They were fabricated through warm caliber rolling with an accumulative area reduction of 93%. Strain-hardening rate at a given strain increased with an increase in volume fraction of cementite particles. The balance of yield strength and uniform elongation for ultrafine-grained structures could be improved by the dispersion of cementite particles. Effects of the cementite dispersion and the ferrite grain size on the strain-hardening rate can be roughly explained by the work-hardening model with GN-dislocation density. Strain-hardening design using dispersed cementites was proved to be effective in controlling ductility of the ultrafine-grained steels.

Jan 1, 2004

By F. Nava-Alonso, A. Uribe-Salas, C. Rodriguez-Rodriguez

Ozone has been proposed to pretreat refractory ores before the cyanidation process for precious metals extraction. As pyrargyrite is one of the silver species most common in Mexican refractory ores, the ozonization of this silver sulfide was studied. The effect of pH and ozone concentration on silver dissolution was evaluated by means of a factorial experimental design. Two levels of sulfuric acid concentration and ozone in gas concentration were evaluated: 0.18 and 0.72 mol/L of acid and 0.054 and 0.077 gO3/L, respectively. The highest silver dissolution was obtained when using the higher acid and ozone concentration.

Jan 1, 2011

By B. R. McEwen, A. N. Samis, J. H. Gray

"The Quebrada Blanca Copper Mine is an open pit copper project located at 4200 m elevation in the Chilean Andes. The deposit is a world-class supergene enriched porphyry with a mining reserve of 89 Mt of 1.3% copper. The supergene zone will produce 6.3 Mt of ore per year for more than 15 years to produce 75 000 t of cathode copper per year.This paper will review the project geology the computer model ling of the deposit, the mine planning process and the property production scheduling. With copper production .fixed by the onsite electrowinning capacity, the planning and scheduling aspects to optimize the project NPV will be discussed. Some of the logistics, equipment. personnel and process difficulties of operating a mine at 42()() m elevation will also be described. IntroductionProject DescriptionThe Quebrada Blanca Copper Mine is an open pit copper project located in the northern part of the Chilean Andes. The project is based on the supergene enriched portion of a porphyry deposit which has a mining reserve of 89 million tonnes at 1.3070 copper. Below the enrichment blanket, the protore represents a further resource.All ore will be leached, the higher grade material will be crushed and stacked for thin layer heap leaching, and the lower grade and oxide material will be dump leached as run-of-mine material. Solvent extraction and electrowinning will be used to produce 75 000 tonnes of cathode copper per year. Power will be supplied by a 40 MW on-site diesel generating plant with the waste heat being used for process heating. The leaching operation will operate in excess of 15 years and may be followed by open pit mining and conventional ore concentration of the underlying primary sulphide mineralization.Because of the dry location water will be piped 37 km from a ground water source at the Salar de Michincha. Water requirements will be approximately 1.5 million m3/year. The operation will eventually employ approximately 550 people on a 7-day-on, 7-day-off rotation with two twelve-hour shifts per day with an on-site camp. Busing will be provided to the port city of Iquique."

Jan 1, 1994

By A. C. Moerman, C. W. Pelley, K. R. Notley

"The software package described in this paper facilitates the handling of diamond drilling information in the creation and maintenance of a geological information database. Once entered, the drilling information is stored in a direct access file for rapid retrieval. The drill data are sorted into vertical cross sections and interpretation is performed using on-screen menus to define areas of common rock type and outline the mineralized zones. Intersections of individual zones can then be examined and outlined in the longitudinal dimension at a graphics terminal.With the aid of surface-fitting routines, the digitized information can be used to generate three-dimensional models of each zone. From these models intermediate cross sections and level plans can be obtained. Several interpretations are possible and plotter drawings can be obtained. An output file for use by ore reserve estimation software can also be created.Future work will tie this software to geostatistics and mine planning programs and will be aimed at converting mainframe software to run on microcomputers. IntroductionComputer applications in underground mine planning and geology are not new. Operations such as Sherritt Gordono and Kidd Creek have been using software developed about a decade ago for handling geological information and designing stoping blocks. However, general use of such systems has been limited mainly due to the cost of hardware which was affordable only to large corporations. Software to perform the work was usually developed on site and was largely unavailable for use by others, being site-specific, or too expensive for other organizations to purchase.The increasing power of microcomputers and mini-computers, and their relatively low cost compared to the mainframe computers which were previously used, has led to the increased use of computers at mining operations of all sizes. Sources of software for use in geological interpretation and mine planning have increased in number with the proliferation of the use of microcomputers."

Jan 1, 1988

By K. C. Corin, M. S. Manono, J. G. Wiese

Depressants play a crucial role in the flotation of PGM bearing ores as they prevent naturally floatable gangue (NFG) from reporting to the concentrate. This action is regarded as critically important because less dilution of the concentrate means lower costs for downstream processes. However, abnormal water conditions (such as high concentrations of ions) in the flotation system can modify the selectivity of these depressants. It is well known that the existence of selected electrolytes in water can alter the behaviour of some polysaccharide depressants by enhancing their adsorption onto gangue minerals and thereby prevent naturally floatable gangue from moving into the froth phase. Concurrently these same electrolytes may enhance frothability, owing to their stabilising effect on the bubbles within the system. Plant water at various ionic strengths was investigated against depressant type and dosage in order to understand electrolyte-depressant interactive effects during the flotation of a Merensky ore, using entrainment, rate of NFG recovery, and total gangue recovery as proxies. The study showed that the rate of NFG recovery per unit mass of water decreased with increasing ionic strength at all dosages, however the total amount of gangue reporting to the concentrate increased with increasing ionic strength at all depressant dosages. Thus, this paper attempts to consider the effects of both ionic strength and depressant dosage as individual factors within flotation. It further looks to investigate whether any interactive effects exists between these two factors when considered simultaneously.

Jan 1, 2016

By V. V. Zubkov

The systems of geophysical monitoring have been already put into operation at coal mines and ore mines. Since at present it is rather difficult to conduct mine experiments; it is necessary to start a new step in joining of geomechanics and seismic. The linking geomechanical and geophysical monitoring at coal mines and ore mines today became possible due to progress in development of numerical methods of modeling of stress state and technology for processing of seismic information. This paper describes one potential step in linking geomechanical and seismic monitoring at coal mines and ore mines.

Aug 1, 2013

By Brian Hart, Stamen Dimov, Aparup Chattopadhyay, Barun K. Gorain

"A novel gold deportment technique has been developed for complex copper-gold and double refractory gold ores using state-of-the-art technology. Characterization of these ores is a challenging task due to low copper and gold grades in ores, presence of both primary and secondary copper sulfide phases and variable proportion of visible and invisible gold in different sulfides and iron oxide phases.Double refractory ores are mainly composed of silicates and carbonates with moderate clay and mica, and minor amounts of sulfides and organic carbonaceous matter. Gold mostly occurs as ""invisible gold"" (sub-microscopic gold) as solid solution or as colloidal-sized particles in different sulfides and other phases. The dominance of invisible gold and presence of highly preg-robbing and finely disseminated carbonaceous matter adversely affects gold recovery in flotation and leach circuits. Characterization of this carbonaceous matter, commonly known as TCM and quantification of gold associated within TCM, along with different sulfide and oxide phases is highly complex and challenging.Studies were initiated on various complex ore deposits and also on samples representing various process streams. This paper presents the development of a systematic approach to diagnostic metallurgy using state-of-the-art optical and automated mineralogy techniques, namely, micro-probe, dynamic SIMS and TOF-SIMS analysis for quantification of invisible and visible precious metal content in various species. The relevance of the mineralogy characterization to metallurgy will also be discussed in this paper."

Jan 1, 2016

By Norman A. M Macleod

FOR the past seven years, all flotation at the Britannia mill has been done in Forrester Air-Lift cells. Prior to 1931, the roughing and part of the cleaning operation had been performed in four 21-cell and two 14-cell M.S. machines. The resulting economies in reagent, power, maintenance, and general operating costs, and the increased recovery, more than justified the exclusive use of the Forrester machine. About three years ago, the possibility of still further improving the efficiency of the flotation section was the subject of considerable discussion and experiment. Arising from these experiments, tests were made of the practicability of using a cell of greater depth than that of any pneumatic or mechanically-agitated machine in common use. Cells were constructed with depths of 7 .5 feet, 10 feet, and 15 feet, and, in all cases, a very definite improvement in operation was indicated. The cell now being used in the mill treats from 5,500 to 6,200 tons of dry feed per day. It is 100 ft. long by 5 ft. wide by 8 ft. deep, and has replaced a total length of over 500 feet of standard Forrester machine. The choice of a depth of 8 feet was governed by the type of blower which was available-in this case, a Roots-Connersville blower, driven by a synchronous motor and delivering 6,000 c.f.m. of free air at 4.0 pounds per square inch. At the Chelan Division of the Howe Sound Company, where a new mill was recently built, all flotation is carried on in cells 10 feet deep, with good results.

Jan 1, 1938

By M. Leijd, K. S. Forrester, M. Saxon, M. Oczlon

This paper provides an introduction to wet high intensity magnetic separation (WHIMS) and its successful application to the beneficiation of rare earth element (REE) enriched eudialyte. The analysis includes an in-depth reporting of the deportment of key elements as well as a statistical interpretation of the relative importance of operational parameters including magnetic field intensity, flow velocity, and matrix loading density. Conclusions are drawn on the relative success of the technology, potential areas for process improvement, and the research direction that continues to be investigated. Three original equipment manufacturer (OEM) technologies were subjected to a series of screening and characterization tests to identify the optimal operating parameter set to magnetically beneficiate eudialyte from Norra Kärr, Sweden. Upon the completion of the characterization test it was apparent that the Metso HGMS technology was superior with respect to REE recovery and gangue rejection for the Norra Kärr composite. The Metso HGMS was then subjected to a series of verification tests to confirm the repeatability and reproducibility of the system.

Jan 1, 2014

By W. A. Jones

"The Ross mine, a subsidiary operation of Hollinger Consolidated Gold Mines, Limited, is near the north end of lot 1, con. II, Hislop tp., Ontario. The property comprises the north half of lot 1, con. II, and the south onethird of lot 1, con. III. It is readily reached by a good motor road from the village of Ramore, 7 1/2 miles to the southeast on the Ontario Northland railway. The mine is being developed to a depth of 1,500 feet, and the current daily production rate is approximately 300 tons. From the inception of operations in March 1935 until December 31, 1945, 692,000 tons of ore, with a total value of $5,762,685, was milled . The silver to gold ratio of 1.48 to 1 is unusually high for Ontario gold mines.TYPE OF 0REBODIES AND MINERALIZATIONThe orebodies consist of lens-shaped and pipe-like stringer lodes and tabular vein zones composed of parallel quartz stringers. The host rocks are steeply inclined eruptive breccias and tuffs, striking N.70°W., intruded by very small stocks of red syenite. The orebodies appear to be spatially related to an intricate system of fault planes. Hydrothermal alteration is widespread and is not zonally related to individual quartz stringers. The wall-rocks contain abundant fine-grained pyrite, but gold is confined to the quartz stringers.RELATIONSHIP TO REGIONAL STRUCTURELack of outcrops has prevented the detailed mapping of the Keewatin complex in the vicinity of the Ross mine with the degree of success that has been achieved in the Porcupine area.A northwesterly trending belt of slates and greywackes, bounded by faults, forms the central part of a broad anticlinal arch about 3 1/2 miles north of the Ross shaft. Lava flows forming the south flank of the structure face south toward the mine. If the sediments are to be tentatively correlated with the large areas of Keewatin slates and greywackes of the Porcupine area, it must be assumed that they are younger than the lava flows and that they have been down-faulted."

Jan 1, 1954

By L. Byszynski

The results of a three month evaluation of the application of EMEW® technology at the KGHM Glogów II Smelter tank house bleed stream are presented. The current, conven¬tional electrolyte decopperization process has some limitations, including: only a fraction of its production is commercial grade cathode copper, significant operating costs, low current efficiency, low current densities resulting in low copper depletion rate, and arsine gas and sulphuric acid emission. The EMEW® cell technology developed by Electrometals Technologies Ltd. can overcome many of these limitations. Tests were performed on a pilot EMEW® installation comprising 30 cells at ambient temperature on electrolyte bleed, using current densities between 100 and 600 A/m2 , with copper concentrations between 45 and <1g/dm3. Results showed that a high grade copper can be obtained to the level of 7 g/dm3 of copper concentration in electrolyte. The use of EMEW® technology allows the direct and efficient recovery of over 85% of the copper contained in the bleed electrolyte. Glue & thiourea addition were tested in order to improve the parameters of the copper depletion process. The behavior of Arsenic and Bismuth was observed and a means for their elimination from the system proposed. On-line copper concentration monitoring is proposed to improve control and performance.

Jan 1, 2007

By Mike D. Riley, Alan V. Bell, Ernest K. Yanful

Acid mine drainage (AMD) research under the MEND program has been ongoing since 1988 at the Heath Steele Mines waste rock piles including sulphide material, outside Newcastle, NB. In 1989 approximately 10,000 mt of waste rock was placed on a prepared sand base with an underlying impermeable membrane. The waste rock pile was heavily instrumented for measuring oxygen concentrations and temperatures. In September 1991, a composite soil cover designed for the Heath Steele climatic conditions, using local soils, was placed over the pile, creating a totally enclosed system. Moisture content and oxygen probes were installed within the composite soil cover to monitor changes within the soils over time, while two large-size lysimeters were installed below the cover to monitor the hydraulic conductivity of the cover. The waste rock site has been monitored on a monthly basis since installation of the cover, for performance of both cover and waste rock. The monitoring shows very clearly that the placement of the composite soil cover has had a major impact on the generation of AMD. Major reductions in temperature and oxygen concentrations within the waste rock pile indicate that the cover has significantly inhibited the oxidation reaction that generates the AMD. Performance data have shown that the cover has maintained its integrity under the climatic conditions of the area.

Jan 1, 1995