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By Víctor De la Cruz

Dado que la mina Rosaura (Lima) se dedica a la explotación de minerales polimetálicos como el zinc, plomo, cobre y plata, la caracterización geomecánica de su estructura, morfología y reservas demostró una tendencia hacia los métodos masivos -en tanto presenta ventajas técnico-económicas comparativas frente a otros posibles métodos como el corte y relleno y conjunto de cuadros. Por ello, el presente texto describe el método de “Hundimiento por Subniveles” (Sub Level Caving – SLC), como el más indicado. El SLC se basa en la utilización del flujo gravitacional del mineral fragmentado a través de la perforación, voladura, y el hundimiento de la roca estéril principalmente de la caja techo. El diseño del elipsoide de extracción determinará la ubicación de los Sub niveles y Drawpoints, los cuales serán críticos para hacer rentable el minado, de forma que los beneficios actuales del método indican niveles altos de Seguridad, recuperación alta de mineral, bajos costos y mejora constante de la productividad.

Sep 9, 2007

The Karangahake gold-silver deposit is located 11 km west of Waihi in the southern part of the Hauraki Goldfield. Historically it was the second largest bullion producer in the goldfield with a past production (1882 - 1944) of 126.712 tonnes of gold-silver bullion (Au:Ag ratio of 1:3.3) from 1 142 315 tonnes of ore grading 27.4 g/tonne gold equivalents.

Jan 1, 1987

By Shemek Oginski

The 5 km (16,194 lf) of 6.1m (20 ft) diameter TBM driven tunnel built by the J.F.Shea Co. will serve as sewage overflow storage. The TBM tunnel and four connecting tunnels excavated by drill and blast methods in hard granite will remain unlined. Based on the Geotechnical Baseline Report (GBR), the Contract documents provided a design with no required pattern of rock bolts, no probing, no pre-excavation or consolidation grouting, and lastly, no final lining of the tunnels was deemed necessary. This paper will provide a general overview of these topics with the emphasis on the actual ground conditions encountered versus the projected conditions provided in the GBR and how the GBR reflected the design of the project. Proposed modifications to the temporary and permanent ground support will be presented and the necessity of probing and pre-excavation grouting will be evaluated.

Jan 1, 2005

This paper will trace the development of underground coal mining machinery from the days of the tiny air-powered machines to today's 60-ton electric-powered continuous miners. Some important design features which have made the modern fixed-drum continuous miner a success will be examined.

Jan 1, 1978

By S. Ross, M. Mayhew

"Kirkland Lake Gold introduced battery equipped vehicles (BEVs) at the Macassa Mine in 2011. The fleet of underground BEV haulage trucks and loaders has grown over the years to over 30 units, the world’s largest, currently handling approximately 80% of the daily production tonnage. The inflow and outflow of air occur through a limited number of relatively small openings, which limits the air volume delivered to the underground workings. In addition to improving air quality, the reduced heat load generated by the BEV (when compared to diesel equipment) had a significant positive impact in the workplace. The use of BEV for material handling has enabled increases in production that would not have been possible using diesel equipment.INTRODUCTIONMacassa mine was developed as a track-drift access mine, with the most recent shaft (#3) sunk in 1986. A new mining complex, the South Mine Complex (SMC) was discovered below the 5025 foot elevation south of traditional mining areas, and the majority of mining now occurs in the SMC. The discovery of that zone has led to an internal ramp which is used to access the SMC and haul ore to #3 shaft.The amount of airflow that can be moved through the mine is limited by the existing infrastructure to surface. This amount was recently increased to near its practical maximum from 118 CMS (250 kCFM) to 151 CMS (320 kCFM).Both diesel and electric equipment are used at Macassa. Tethered Load-Haul-Dump Machines (LHDs) have been replaced with Battery Electric LHDs, due to their increased mobility and depth of the mine. Battery trucks continue to replace locomotives to transport both ore and waste to the shaft, as mining has transitioned from tracked levels to trackless level and haulage has transitioned from horizontal levels to an inclined ramp.EQUIPMENT FLEET AT MACASSAMost of the primary material movers utilized at Macassa Mine are battery operated. As the mine goes deeper the battery technology will continue to be critical to the success of the operations. With over 300,000 hours of proven operation success, the battery technology and equipment will continue to be a major part of Macassa’s future."

Jan 1, 2019

By G. Simard, M. J. Gagnon, A. Charette, G. Péloquin

"In the Bayer process, flocculants are introduced in the feed well to enhance the aggregation of red mud particles. To gain a better understanding of the flocculation process taking place in the feed well, shearinduced flocculation was achieved using concentric rotating cylinders (Couette system). Our previous work has shown the effect of the shear rate on the aggregate’s settling rate and on residual turbidity of the Bayer liquor. In this study, the data demonstrated that the aggregates at selected shear levels appear as a population with a widespread size distribution. By using an imagery apparatus, it was possible to measure the size, the shape, and the sedimentation velocity of the larger red mud aggregates. Marked differences were noticed in the characteristics of the aggregate populations obtained under various shear conditions. IntroductionIn the Bayer process, red mud particles are separated from the liquor in primary clarifiers and washing circuits under the action of synthetic polymers. The agitation in the feed pipe and in the feed well affects the flocculation since the aggregates are formed by the interaction between the red mud particles and the polymers. A minimum shear rate is needed to initiate the aggregation process of fine particles (Warren, 1975).Different systems have been used to study the effects of shear on the flocculation process (Tampo and Watanabe, 1979; Klimpel and Hogg, 1986; Scott et al., 1996; Biggs and Lant, 2000). The Couette flow system has been used in some studies on shear-flocculation (Oles, 1992; Farrow and Swift, 1996a, 1996b). The importance of the physical properties of the aggregates in determining the efficiency of the solid-liquid separation process within a given gravity thickener has been demonstrated (Farrow and Warren, 1989a)"

Jan 1, 2002

By B Chi, A Mahanta, R A. M Maddever, O Dominguez

BHP Billiton, in collaboration with Sodern and CSIRO, has developed a downhole logging tool for measuring geochemistry in situ. The FastGradeTM 100 (alternatively, FG100), exploits pulsed fast and thermal neutron analysis (PFTNA) to analyse the rock. This method is based on the detection and measurement of characteristic gamma rays emitted from isotopes in the material that become briefly radioactive when they are bombarded with neutrons. The tool outputs raw spectra arising from three types of neutron interaction, namely, inelastic scattering, neutron capture and neutron activation, which occur in successive time-windows (Smith et al, 2015). The spectra contain peaks at specific energies that are characteristic of the different elements interacting with the neutrons, the gamma count of which is related to elemental concentration. BHP Billiton uses in-house data processing software to convert the measured spectra to elemental concentrations.Much work has been done to understand the tool response under a wide variety of environmental and operating conditions, including logging speed, borehole rugosity, the presence of cavities, water etc. Effort has also been directed at understanding and quantifying the current sources of error in our conventional assays due to sample collection, preparation, and laboratory instrumentation in order to use this information as a baseline to compare against the FastGradeTM 100 results.To date, the FastGradeTM 100 primary use has been as a verification tool (JORC, 2012). However, beyond this, it has considerable potential to improve productivity in both exploration and production environments due to its ability to provide geologists with assay results soon after a hole is drilled.This paper presents initial test work and tool performance, including accuracy and precision under various conditions. Results are illustrated by comparing tool measurements to assays from laboratory samples collected from both reverse circulation and diamond-drilled holes.CITATION:Chi, B, Maddever, R A M, Mahanta, A and Dominguez, O, 2017. Near real-time assay with downhole assay tool (FastGrade™ 100), in Proceedings Eighth World Conference on Sampling and Blending , pp 137–144 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By Scott G. Giltner, Paul N. Worsey

During the short duration of an explosive blast, many events occur which are too quick to be detected or observed in detail with the naked eye or by normal photographic techniques. Through the use of "hightech", high speed video, many of these events can be observed, instantly played back and recorded for later use. The use of a Spin Physics SP 2000 Motion Analysis System at a blast casting operation is presented. The variable range of recording speeds offered by the SP 2000 allowed it to be used for examination of different areas of blasts. At its maximum full frame rate of 2000 frames per second the SP 2000 can easily pick up the flame front as it travels down a nonel tube and the flash from the surface delays as they fire. The system was used for a variety of tasks including, but not limited to,the determination of delay accuracy to within 0.5 ms, the velocity and trajectory of the faces during blasts, and pinpointing geological problem areas. The effectiveness of the system as used on site is discussed along with detailed method of set up, recording, playback and data processing. Other details including site specific environmental and lighting problems are also covered.

Jan 1, 1986

By Thomas S. West

A gravel pack completion is described which, in addition to sand screening, permits the exclusion of water and gas from the oil production. A gravel pack composed of alternate layers of different particle sizes is employed which has horizontal but not overall vertical permeability to drilling mud. A packer is run on the tubing and set in the screen member, around which the gravel layers are placed. The hydrostatic pressure of a mud column prevents the entry of fluid above (or below) the level of the packer. The producing level may be changed by raising or lowering the tubing. Vertical coning is controlled by replacing the mud column with oil and continually injecting oil into the sand section above (or below) the packer. Three well histories with this completion are described in detail. Statistics on the first 100 completions of this general type are given. INTRODUCTION Gravel pack type completions have heretofore been almost exclusively for the purpose of preventing sand production. This paper describes and presents well data on a gravel pack procedure which is primarily a selective completion method. Although complete sand screening is achieved, the exclusion of gas and water is the primary objective. The application of this procedure is therefore not limited to unconsolidated sands. Application to hard sand or limestone reservoirs is equally feasible. GRAVEL PACK PROCEDURE Figs. 1 and 2 illustrate the gravel pack procedure employed. The gravel is placed by means of the frangible disc type dump bailer shown by Fig. 1.' This bailer has its lower end closed by a plate glass or steel rimmed cement disc. This disc breaks when the bailer passes over the liner allowing the gravel to be deposited around the liner. The liner employed is usually 2 3/8 in. to 2 7/8 in. OD and 1.995 in. or 2.07 in. ID (ID of 2-in. tubing or 2-in. line pipe). Two tvDes,. of slotted sections have been employed. One type employs horizontal hacksaw cut or milled slots of about 1/32 in. width opposite the producing section. The other type employs the same type,. of horizontal slot. but slots are placed in groups of six at intervals of about 8 in. A cage composed of half round vertical bars, spaced apart, is then welded to the pipe over the slotted sections. This liner has the bottom end closed, usually by bull plugging. The upper end is closed, while placing the gravel, by a cap which is held in place by means of a shear pin. This cap has a mandrel attached to it which extends downward inside of the liner to within a few inches of its lower end. The top of the liner cap is formed to fit a releasing type wire line core barrel overshot. The liner is lowered to bottom on the wire line by means of this overshot and released. The length of the liner is usually suffi- cient to extend to about 20 ft above the highest level to which gravel is to be placed, the upper end of the liner always being in the casing. The dimensions of the liner and bailer are such with respect to the casing size that the bailer will always pass over the liner. After releasing the liner the bailer is run to bottom. Passage of the empty

Jan 1, 1951

concentrations) and physical nature of receiving streams, which in turn affects the stream ecosystem. Benthic macroinvertebrates are used to illustrate these impacts, and to investigate natural recovery in affected streams. In Charming Creek, a severely impacted stream in the Buller District, the macroinvertebrate community recovers diversity and the proportion of sensitive species (EPT) in the community is more significant with increasing downstream distance from the source of AMD. This is most likely due to dilution of AMD contaminated water by tributaries to the Charming Creek mainstream. Other impacted systems with less dilution from tributaries did not display similar levels of recovery. The effectiveness of remediation products BauxsolÖ and Zeolite was investigated using laboratory trials. Both products mitigated the toxicity of AMD and enhanced the survival of mayflies exposed to AMD contaminated water. Such products may be of use in the New Zealand environment but are likely to be most effective in conjunction with other systems (eg wetlands). Mitigating the impacts of AMD on stream ecosystems needs to include systems to directly address water chemistry issues (low pH, high metal concentrations) as a component of a holistic approach to restoring environmental conditions.

Jan 1, 2003

By Katherine L. Heineken, Timothy J. Tope, Kim David Murphy

One method for small arms disposal is the use of a deactivation furnace or explosive waste incinerator. There are numerous hurdles a facility typically encounters to get the furnace or incinerator fully operational and permitted. For example, one Department of Defense installation was in the permitting process 7 years, which included numerous facility upgrades and modifications. This paper will discuss the technical approach for proactively addressing permitting issues and requirements and will identify potential pitfalls to avoid as well as ways to reduce costs. For example, when determining the waste profile, the facility should forecast its treatment needs (taking into account the net explosive weight limits of the furnace/incinerator) and then classify the wastes into "chemical families" based on the type and composition of the wastes. One waste from each family should then be selected for potential inclusion in the trial burn. Modeling the waste disposal can help to narrow down the number of wastes requiring characterization during a trial burn, as well as the number of analyses.

Jan 1, 1997

By Milton H. Ward

The percentage of exploration dollars flowing out of the industrialized countries continues at an all-time high, and this shift in risk money is justified (Samuels, 1990; Bosson, 1977). Clearly, the odds of discovery are greatly enhanced if exploration is pursued in an untrampled and geologically more prospective environment. Unfortunately, such major unexplored areas of the developed world are shrinking rapidly, not just because the lands have already been tested, but primarily because they have been withdrawn from exploration. Experience, however, has shown that foreign investment is not without risks. These include problems that result from working in isolated areas, a lack of infrastructure, untrained workers and an absence of a solid geological data base. While the likelihood of once-feared expropriation is now low, mining enterprises still must take precautions to gain the support of their constituencies, including a variety of governments (local, provincial and central), workers, environmentalists, cultural organizations and local landowners. Is foreign exploration worth the risk? In most cases, Yes! But maintaining tenure and long-term success in a less developed country is only likely with good planning and the use of appropriate safeguards. These include measures such as buying country-risk insurance, building multinational relationships, forming joint investments, developing a broad customer base and seeking local investors in the company (Cobbe, 1979). The primary theme of this lecture is: How a company handles its constituency is critical to long-term tenure in a foreign country. Ideally, a multinational mining company would be so effective in dealing with the local people and managing its relationship with the host government that it would become a preferred employer, preferred over its competitors and over local companies. Historical overview Our earliest ancestors lived in Africa three to four million years ago. The Paleolithic or Old Stone Age, about 500,000 years ago, marked the beginning of mining in its earliest form (Gregory, 1980; Wolf, 1984). Various types of rocks and stones were used for tools and weapons, with flint being the preferred resource for implements. Initially, these materials were collected as stones (eoliths) lying on the surface. Then they came from excavations of flint in limestone beds that were exposed in river banks or naturally occurring excavations. Later, more formal mining developed. No doubt tribes of the Old Stone Age experienced conflict over rights to eoliths, food and land. The question of who owns the land and has rights to its contents and what is fair value for extraction is still the subject of intense debate and, occasionally, open conflict. As time passed, the search for useful minerals required migration from one area to another. Later, voyages from Europe to the New World and travels to other remote regions were funded and supported by absentee investors, kings and such (Rogers, 1976). The primary objective of such funding was to obtain gold, silver, food stuffs and other commodities that could be collected from the new countries. This is still the objective of foreign investment.

Jan 1, 1994

By J. F. Lupo

There are numerous mines throughout the world that have open pit highwalls developed partially or wholly in soil or soil-like materials. Soil-like materials are considered to include soils (either transported or residual) and highly weathered rock, which may have soil-like behavior. These materials generally have characteristics or material properties that vary considerably from those of moderately weathered or fresh rock. Given these differences, it is important to consider the characteristics of soil-like materials to design safe open pit slopes. In the design of open pit slopes in soil-like materials, it is important to recognize the behavior of these materials is strongly dependent upon their mineralogy, degree of weathering, cementation, stress history, depositional history, and presence of water. As a result, soil-like materials may contain one or more of the following characteristics that can have a significant effect slope stability and design: - Relict structural features (joints, faults, etc), - Sensitivity to moisture (both wetting and drying), - Zones of alteration with variable strength and drainage characteristics, - Zones of low permeability creating perched ground water conditions, and - Undrained and drained strain softening or strain hardening behavior.

Jan 1, 2011

By Eugene T. Sheridan

This report presents data on individual plants of the fuel-briquet and packaged-fuel industries that were circularized by the Bureau of Mines, United States Department of the Interior, in its annual survey for 1958. Only plants that processed fuels of mineral origin were included; specifically, plants that manufactured briquets from charcoal were excluded. Fuel briquets and packaged fuel are manufactured by mixing fine-sized fuels with binders and compressing into small individual shapes. Both are used mainly for residential heating in the United States, but they differ considerably in appearance and physical characteristics. Briquets usually are produced as small, pillow-shaped forms, 2 to 4 inches in length, weighing from 2 to 4 ounces. Pack-aged fuel consists of 3-to 4-inch cubes, 6 or 8 of which are wrapped in heavy kraft paper to form a package weighing 10 to 15 pounds. Briquets are made with a water-insoluble binder and are designed for rough handling and outdoor storage, whereas packaged fuel generally is made with a water-soluble binder and must be stored indoors to prevent deterioration. Briquet plants are relatively large and usually are at mines or in dock areas where large quantities of fine-sized fuels accumulate. Packaged-fuel plants are smaller and are used chiefly by retail dealers to convert locally available coal and coke fines into a product that can be burned efficiently in residential beating equipment.

Jan 1, 1959

By Gilbert L. Forst

The objective of this program is to identify and evaluate superior, lightweight substitutes for selected coal mine roof support concepts such as crossbars, posts, and crib blocks. Engineering analysis and concept design identified, through tradeoff studies, that some materials are promising, from a technical standpoint, as support substitutes: E-glass reinforced polyester resin, high strength low alloy steel, aluminum, and very high early strength (VHE) cement. An economic analysis indicates that none of the lightweight substitutes are economically competitive with wood on an initial cost basis; however, in terms of life cycle costs based on current dollars, the high strength low alloy steel appears competitive for crossbars, and the VHE cement and E-glass/resin appear competitive for posts.

Jan 1, 1978

By Theodore H. Eyde

In 1971, the Minerals Division of The Superior Oil Company acquired exploration rights to an unpatented claim group in the Superior (Pioneer), Arizona mining district, lying west of the Concentrator fault. This major post-mineral fault displaces the Magma vein-fault, which is mined in the Magma Mine at Superior, Arizona. The Magma vein-fault and the enclosing section of pre-mineral rocks consisting of Paleozoic and younger Precambrian sediments and diabase, is overlain by a thick section of post-mineral rocks, consisting of the Gila conglomerate, the Apache Leap dacite, and the Whitetail conglomerate. Geologic information on the thickness and attitudes of the rocks obtained from previous diamond drilling indicated that the section of post-mineral rocks might be from 3,000 to over 4,010 feet thick in the target area. (Figure 1) The Magma vein-fault is a steeply dipping vein which has produced nearly a billion dollars of copper, zinc, silver, and gold. It has been mined continuously for nearly 10,000 feet along the strike and nearly 5,000, feet vertically down the dip. It ranges from less than a foot to over 50 feet wide and contains sulfide mineralization con¬sisting of pyrite, chalcopyrite, bornite, and chalcocite.

Jan 1, 1973

By A. L. Barnes

Residual oil in watered-out reservoirs is a tremendous reserve which has been unrecoverable by established production methods. A study of the new recovery methods indicated that the forward combustion urocess might- recover oil from such reservoirs; however, no thermal recovery operating experience in a watered-out system was available. The Delaware-Childers pilot thermal test was undertaken to test the feasibility of thermal recovery in this watered-out reservoir. The pilot test consisted of a 2.22-acre, inverted five-spot in the 600-ft deep Bartlesville sand. The reservoir in the pilot area had a porosity of 20.6 per cent, a permeability of 118 md and an average sand thickness of 45 ft. The reservoir contains a 33' API, 6-cp oil. Combustion was started Nov. 22, 1960. The initial air injection capacity was 750 Mscf/D, but it was eventually increased to 2,000 Mscf/D. The test was surrounded by an active water flood; therefore, water production was initially high, but decreased as the heat wave moved toward the producing wells. Oil-bank arrival at an individual well was indicated by a drop in GOR and WOR, and an increase in oil production. Combustion-front arrival was evident at three of the pilot producers, and they were plugged. Cumulative oil production from pilot area wells war over 12,000 bbl. Operational difficulties were negligible and only conventional equipment was necessary. The combustion efficiency of this test averaged over 80 per cent. Results from coring showed that the leading edge of the combustion front tended to be wedge-shaped but a nearly complete sweep of the reservoir was eventually obtained. An isopach map based on evidence from 10 core holes and the existing wells showed that 126 acre-ft had been swept by the heat wave. Using this swept volume, an air requirement of 15.7 MMscf/acre-ft was calculated. It was calculated that 275 ,STB/acre-ft was consumed bv the heat wave. INTRODUCTION There is a large amount of oil remaining in reservoirs that have been water flooded. A study of ways to recover this oil showed that the forward combustion process might be applicable. Results from a number of forward combustion tests have been reported in the literature, but none of these tests were conducted in a watered-out system. The Delaware-Childers pilot thermal test was initiated in 1960 to define the operating characteristics of underground combustion in this watered-out Bartlesville sand reservoir, The purpose of this paper is to present the pilot test results in detail. FORWARD COMBUSTION PROCESS The forward combustion process consists of initiating combustion in the formation surrounding an injection well and driving this heat wave through the formation toward offset producing wells. As the combustion front progresses through the reservoir, oil and formation water are vaporized, driven forward in the gaseous phase, and recon-densed in the cooler part of the formation. These distilled liquids, water of combustion and gaseous combustion products, form a bank or three-phase region ahead of the burning front. This bank pushes mobile reservoir fluids toward the production wells. The rate of movement of the combustion front is controlled by the rate at which the nondistill able residue which serves as process fuel can be completely burned off the sand. The production performance from a heat wave conducted in a watered-out oil reservoir will differ from one conducted in a dissolved gas-depleted reservoir because of the difference in fluid saturations. The primary depleted reservoir contains connate water saturation, relatively high oil saturation and some gas saturation. The watered-out reservoir contains a highly mobile water saturation, residual oil saturation and little gas saturation. As the combustion front moves forward in either type of depleted reservoir, it drives the distillable oil, the water in place and the water of combustion ahead, and burns the nondistillable portion of the oil. The heat-wave process in a watered-out reservoir differs from the process in a

Jan 1, 1966

By Kazusuke Sato, Takahiro Uno, Koji Hoshino

"A novel Ni coating technique of Ni(OH)2 powders was developed to improve the positive-electrode performance· of the Ni-MH batteries. It was found out that Ni(OH)2 powder was reduced by N2H4 without any catalysts in an alkaline - solution at high temperatures. In result of observation of pH and potential changes in the solution during the reaction, it was found that the reduced species was HNio2- ion dissociated from Ni(OH)2 in the alkaline solution. The molar fraction of reduced Ni of the Ni(OH)2 was increased in proportion to the amount of added N2H4. At the small Ni fraction, a porous Ni layer was formed on the surface of Ni(OH)2 powder. Open cell tests were carried out with the paste type electrodes made of either the Ni coated Ni(OH)2 powder or non-coat powder, and cell performances were compared. In result, it was found that the Ni coating technique is effective on improvement in the utilization of Ni(OH); as a positive-electrode active material under high current densities.IntroductionNi-MH rechargeable battery is generally used for the power source of portable machines and electric vehicles because of its good performance at high energy density and. long term cyclical life as well as cleanness and good safety. Cell component materials have been improved respectively, and as concerns ·the positive-electrode reducing 'the internal resistance is a principal problem to improve the discharging performance at higher current densities.In recent years, improved Ni(OH)2 powders coated with conductive materials as NI. or CoOOH have been developed for the· positive-electrode active materials in order to· reduce the internal resistance of the electrode1)· 2) The Ni coated Ni(OH)2, however, is costly because it is fabricated by .the -non-electrode plate technique which needs a expensive precious ·metal catalyst as PdC12We found that Ni(OH)2 powder was reduced by N2H4 without any cryatalysts in an alkaline solution at high temperatures. After the treatment, Ni(OH)2 powder become gray color like Ni powder from light-green color; and. turned into a magnetic. In this study, the mechanism of the -reducing reaction was investigated to apply the reactions .to a novel Ni coating technique of Ni(OH)2 powders, · and the performance of the Ni coated Ni(OH)2 powder obtained by the reducing process was evaluated as an -positive-electrode active material of Ni-MH batteries."

Jan 1, 2000

The annual reports of the supervising engineer of the seven sections comprising the Mining Division are assembled in the following pages and form the annual report of the division. In planning activities, the aim has been to adapt the work to changing conditions and needs of the mining industries and to avoid becoming bound to any particular type of investigation when others are found to be of more pressing interest.

Jan 1, 1939

By A. S. Mallicis, Li Xiawoei, P. W. Weiblen, I. Iwasakl

Platinum group metals (PGM) are often found in close association with arsenide and sulfarsenide minerals in copper-nickel bearing gabbroic rocks. Major losses of platinum in flotation have been attributed to the susceptibilities of the arsenic minerals to oxidation and subsequent losses of their recoveries in cleaner flotation stages. The use of a nitrogen atmosphere in grinding and in flotation, the effectiveness of activation for improving their floatabilities, and the role that electrochemical interactions play not only between grinding media and minerals, but also among different minerals, are discussed.

Jan 1, 1989