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By Muto S, Okada S

At Tamano Smelter, part of the furnace settler is electrically heated by electrodes placed internally. This practice provides good control of the settler conditions. The authors have been investigating improvements in furnace operations, especially to decrease the copper content in the slag discarded from the settler. The important operational points on the control of magnetite in liquid matte and slag are discussed on the basis of the thermodynamic calculation method developed by Prof. S. Goto. The behaviour of magnetite in the practical furnace has been studied by using a torsion magnetometer and a solid electrolyte oxygen-sensing cell.

Jan 1, 1980

By Vinay Kumar

The disposal of large quantities of electronic scraps generated world wide is causing not only environmental problem but also loss of resources. Therefore, R & D efforts have been made to develop a suitable process for extraction and separation of metals viz. copper, zinc, cadmium and nickel expected from the leaching of e-scraps using solvent extraction process. Different process parameters viz. pH, aqueous to organic ratio, kinetics of extraction, extraction isotherm to establish stage requirement for extraction in continuous mode etc have been studied to optimise the condition for the separation of metals. The studies showed the selective extraction of copper after iron precipitation from the sulfuric acid leach solution of e- wastes containing ~1.0 g/L Cu and minor impurities with 2-hydroxy-5- nonylacetophenoneoxime (LIX 84) above pH 2.0 in single stage. A scheme for separation of cadmium, zinc and nickel has been proposed using di(2-ethylhexyl) phosphoric acid (D2EHPA) under controlled pH of the aqueous solution. The order of extraction was found to be Zn> Cd> Ni.

Jan 1, 2009

By A. D. Hammond

Until recently, the volumes delivered and unloaded from heap-leaching pads have been estimated by manual methods at Wharf Resources' South Dakota operation. In August 1989, the Engineering Department acquired the MINE-SURVEY software developed by GEM COM Services, Inc. of Vancouver, Canada, as part of a mine planning/grade control software package. The implementation of MINE-SURVEY for pad control resulted in a cost-effective tool to provide accurate and prompt estimates of ore delivered or unloaded from the pads. Volumes can be calculated in a matter of minutes as opposed to hours or days. Another benefit is the ease of comparison of as-build and designed volumes, plotting cross-section in any orientation, importing into AUTOCAD, validation of ore densities and truck factors. This paper describes the application of the MINE-SURVEY systems in heap leaching pad volumetrics.

Jan 1, 1991

By Howard Evans

Moderate but substantive gains were recorded in 1972 in the minerals processing industry. In the area of mill design, a number of large plants under construction during the past two to three years were tuned up and went into production. The application of operating controls has also made some significant strides. Progress here has been made in the areas of on-stream particle size analysis, on-stream x-ray analysis, slurry transportation, tripper control, flotation reagent control and digital control of grinding circuits. The major contributions to improved equipment are coming from smaller specialized equipment makers.

Jan 2, 1973

By R. Winand, M. Degrez, C. Temmerman

"The influence of the copper electro crystallization inhibitors (mainly thiourea, gelatin and chloride ions) is studied in a new fully automatic pilot plan. This paper describes the conception and the building of this plan. The new approach is to reproduce the experimental conditions observed in the industry with the three additives present simultaneously in the electrolyte and secondly to study the influence of a slight modification of the concentration of one inhibitor, the others being present in the electrolyte with their industrial nominalconcentrations.1. INTRODUCTIONDespite the fact that gelatine, thiourea and chloride ions have been used in copper electrorefining for a long time, precise knowledge concerning their influence on the cathode deposit, metallographic structure and associated properties is still lacking.Many authors studied the influence of each additive separately, or of two added at a time. Only a few authors studied the combined influence of the three additives added simultaneously. The general conclusion that can be drawn is that the combined influence is far from that forseen from the influence of each additive separately, or even from two additives used at a time. Moreover most of the experiments described in the literature were performed by adding all additives at once initially. It is however, well known that gelatine looses a great part of its activity during the first half hour due to degradation by sulfuric acid (as shown by the cathode overpotential drop). Thiourea is rapidly replaced by a number of degradation mole,cules and complex ions including cations from the solution, changing even the equilibrium between Cu, Cu(I) and Cu(II).Chloride ions are consumed by precipitation.A number of successive research projects [1-9] led pregressively to the concept that, in order to obtain reproducible results representative of industrial cathodes, it was necessary to simulate as far as possible industrial conditions. It was essential that all additives were added continuously during the electrolysis, with, as consequence, a continuous bleed.The purpose of this paper is to describe the concept of a new fully automatic pilot plan for copper electrorefining and to present the first results."

Jan 1, 1997

The concentrating plant of the Broken Hill South Limited was described in Proceedings No. 44, Australasian Institute Mining and Metallurgy, December, 1921, by Wainwright and Read. It was erected on the present site in 1907 and 1908.From that date, the plant has undergone various alterations consistent with metallurgical improvements. By 1925, the timber work of the gravity secti"on had seriously deteriorated, so much so, that, when the machinery was working, the floors and supports vibrated badly, causing heavy maintenance costs.In 1928, it was decided to erect a new gravity-treatment section, to be followed later by a new flotation section.

Jan 1, 1932

By Alex Lowson, Dan Tempelis

The Riverside Badlands Tunnel segment of the Metropolitan Water District of Southern California’s Inland Feeder Project, was lined with a segmented concrete primary lining and a welded steel final lining with the annulus filled with Low-Density Cellular Concrete (really a grout). The paper describes a numerical modeling technique that was developed to determine safe grout placement procedures to avoid pipe flotation, and shows the relationship between flotation and the rheology of the liquid grout. Design details of the steel liners are often not well suited to grout placement, and recommendations are given on how to improve this.

Jan 1, 2003

By Gregory J. Chekan

Developing a coal seam that has been influenced by previous mining in seams either above or below can result in severe ground control problems. In many instances, interactions between operations are inevitable. but improvements in ground stability can usually be achieved by-predicting potential problem areas in advance and adjusting the mining plans accordingly. This report investigates four case studies involving interactions between operations that used both room-and-pillar and longwall mining methods. In each case, geologic and mine design parameters are addressed, and those parameters found critical to the interaction are further defined in relation to observed ground problems.

Jan 1, 1990

By B. R. Queneau

[ ] B. R. QUENEAU-One of the difficulties in metallurgy has always been a lack of precision in measurement, and I think the authors are to be congratulated on developing a method which will give us an accurate and dependable quantitative estimate of the amount of retained austenite. O. ZMESKAL*-As Chairman Queneau said, this is indeed an ingenious and needed determination. We have seen figures presented of 1/2 pct retained austenite determined, and I would like to ask the authors the lower limits of this method. How far down do they feel they can go in improving the technique still more?

Jan 1, 1948

By D. Carr, C. Anderson, M. Deal, C. Larson

"Construction of the OceanaGold Haile operation’s process plant in Kershaw, South Carolina is currently under way, with ore through the mill expected in late 2016 and commercial production expected in early 2017. The process is designed to treat 6,350 tonnes per day with minor upgrades required to achieve 8,270 tonnes per day. Plant optimization during detailed engineering, combined with a focus on de-risking the process, has resulted in numerous process changes since the initial design. This paper describes the plant optimization and de-risking, it also presents a proven commissioning strategy modelled after OceanaGold’s Didipio operation, whilst identifying potential expansion opportunities. INTRODUCTION Haile Gold Mine is located in Kershaw, South Carolina, approximately 50 miles south of Charlotte, North Carolina. Gold was first discovered at the site in 1827, and the property has been through several operating periods since. The last operation employed heap leaching from 1985 through 1992. Since then, the property has been closed and fully reclaimed. Romarco Minerals acquired the property in 2007, and began an exploration program that delineated 2.02Moz. of gold in reserve at an overall grade of 2.06 g/t. OceanaGold acquired Romarco Minerals and the Haile Operation in October of 2015. OceanaGold operates under a risk management philosophy in all aspects of operation, both corporately and at each individual business unit, and has implemented numerous process changes to eliminate or mitigate risks identified in the initial design of the processing circuit, and provided increased opportunity for optimization and expansion. This paper describes the plant optimization and de-risking, it also presents a proven commissioning strategy modelled after OceanaGold’s Didipio Operation, and identifies potential expansion opportunities. INITIAL PROCESSING CIRCUIT DESIGN An extensive metallurgical test work program was undertaken by Romarco Minerals and third party laboratories during the initial design phase of the Haile project [1]. This preliminary test work provided the technical information as a basis of plant design. The initial flow sheet for the Haile processing circuit is shown in Figure 1 (see APPENDIX). The plant is designed to process 6,350 tpd (7,000 stpd) on an annualized basis. The process begins with a jaw crusher followed by a SAG and ball mill grinding circuit to reduce particle size to P80 74 µm. A flash flotation cell treats 50% of the cyclone underflow in the ball mill circuit. Grinding circuit product is sent to a rougher flotation circuit to recover gold-bearing pyrite. The flotation concentrates from flash and rougher flotation are reground to P80 13 µm using stirred media detritors (SMD’s). The rougher flotation tail is pumped to the carbon-in-leach (CIL) circuit for gold recovery. The reground concentrate is pre-aerated prior to being pumped to the CIL circuit. The CIL circuit is a hybrid circuit with eight tanks. Tank 1 leaches the pre-aerated concentrate only, and tanks 2 through 8 leach the combined flotation tailing and tank 1 discharge. The carbon strip circuit is a standard pressure Zadra system, followed by electrowinning, and refining using an induction furnace. CIL tailing passes through a cyanide recovery thickener prior cyanide destruction and then pumped to the tailing storage facility (TSF)."

Jan 1, 2017

By Eugene V. Cilento, R. Clark Lantz, K. A. DiGregorio

"This laboratory bas developed a sensitive electro-optical method to quantify the initial rate (R) and total amount (MAX) of superoxide (02) produced by single pulmonary alveolar macrophages (PAM). The method uses a microscope-based TV system to visualize PAM in culture, and to video record the images during the time the cells produce 02. MAX and R are calculated from measurement of temporal changes in optical density in the images due to precipitated diformazan formed by the reaction of O2-, produced by each PAM, with nitroblue tetrazolium present in the culture medium. To date, values of Rand MAX, measured due to adherence of PAM to the dish, have been compared to values obtained when quartz, coal mine dust (CMD), and kaolin . were added to the medium (in vitro). Rand MAX have also been calculated for PAM lavaged from animals exposed to quartz and CMD in the WVU Inhalation Facility. Presently, experiments are being done using which will permit PAM to be restirnulated by different dusts to help establish a dose response relation~ p and a means to study the role of lung surfactant on modifying the acute toxicity of inbaled dusts. Ultimately, this methodology should provide useful insight into establishing the role of 02 in PAM dysfunction due to inhalation of dusts, and in lung diseases such as pneumoconioses. INTRODOCTIONPAM are free cells found in the lungs which protect the lungs by removing foreign debris and bacteria. This is accomplished, in part, by the process of phagocytosis, whereby foreign matter is internalized into vesicles known as primary phagosomes. Phagocytosis also involves the chemical breakdown of inhaled dusts and the killing of microbes. Detoxification is aided by the respiratory burst, which is a metabolic response of the cell to foreign substances, that results in the production of highly reactive oxidizing agents from the partial reduction of extracellular oxygen to superoxide (02) at the surface of the plasma membrane. Superoxide undergoes either spontaneous or enzyme catalyzed dismutation reactions to form hydrogen peroxide (H202) and subsequently hydroxyl radical (OH•) and singlet oxygen (02 t ). However, while these oxygen metabolites aid in the killing of microbes they also may destroy endogenous tissue. For example, 02 has been linked to the aging process and to many diseases including emphysema, diabetes, and cancer.'' Therefore, a better understanding of the production of 02 is extremely important since an abnonnally low production could result in damage by inhaled dusts and bacteria while an abnormally high production could result in direct damage to the lung tissue by the phagocytes. Inhalation of respirable sized mineral dusts, such as quartz (silica), coal mine dusts (CMD), and asbestos, results in various pulmonary disorders. PAM are thought to play an important role since evidence suggests that the first step in fibrogenesis is an interaction of dust particles with PAM. Generally, in vivo exposure of animals to mineral dusts results in increased respiratory burst activity, migratory patterns, phagocytic behavior, and secretory potential of PAM, and for this reason these have been implicated to be pivotal events in the pathogenesis of pulmonary diseases.1 In addition to stimulation of resident PAM, an influx of monocytes into the lung and/or production of new macrophages generally occurs in response to fibrogenic dust inhalation. Further, PAM may attract and stimulate fibroblasts, which normally synthesize proteins and collagen during rep~ of tissue, by secreting chemoattractants and enzymes. Thus, PAM may be involved in pulmonary disorders through failure or partial loss of their defensive capability, or indirectly, through release of other mediators."

Jan 1, 1990

By D. M. Lane, J. M. Berkoe

Engineers and Owners share a common desire to build reliable, efficient plants on schedule at reasonable costs. This paper describes one tool that Bechtel finds can integrate these objectives by “putting innovation into practice”. Examples of such innovative engineering practice include the use of computational fluid dynamics (CFD) to determine efficient designs. This paper outlines several examples of CFD applications on actual Mining and Metals Projects from around the world. The focus here is to highlight the modeling objectives, analysis strategy, actual benefit obtained from the work, lessons learned to improve future efforts and the common mistakes that can obscure the correct or best results, despite impressive graphics. The tools are powerful, and the results are more powerful when applied with skilled and well-directed human effort and ingenuity.

Jan 1, 2000

By Oliver C. Ralston

The Nonmetals Division studies problems relating to the use of minerals, many of which are important to national defence for purposes other than the extraction of metals. In fact, virtually all of the work of the division has been diverted to investigations pertaining to better use of the Nation's natural nonmetallic is resources as weapons of defense. The experiment stations of the division are at Norris, Tenn.; Tuscaloosa, Ala.; Seattle, Wash.; and College Park, Md. Studies involving the application of electric power to the nonmetallic minerals are conducted at the Electrotechnical Laboratory at Norris, and investigations on mineral-dressing treatment are conducted mainly at the Southern Experiment Station at Tuscaloosa. The cleaning and preparation of coal are studied at both Tuscaloosa and the Northwest Experiment Station Lit Seattle (other projects relating to utilization of coal are conducted by the Coal Division of the Bureau of Mines). Problems covering the use of minerals and fundamental problems as to their properties are studied at College Park.

Jan 1, 1941

By Oliver C. Ralston

The Nonmetals Division studies problems relating to the use of minerals, many of which are important to national defense, for purposes other than the: extraction of metals. In fact, virtually all of the work of the division has been diverted to investigations pertaining to better use of the Nation's natural nonmetallics is resources as weapons of defense. The experiment stations of the division are at Norris, Tenn.; Tuscaloosa, Ala.; Seattle, Wash.; and College Park, Md. Studies involving the application of electric power to the nonmetallic minerals are conducted at the Electrotechnical Laboratory at Norris, and investigations on mineral-dressing treatment are conducted mainly at the Southern Experiment Station at Tuscaloosa. The cleaning and preparation of coal are studied at both Tuscaloosa and the Northwest Experiment Station Lit Seattle (other projects relating to utilization of coal are conducted by the Coal Division of they Bureau of Mines). Problems covering the use of minerals and fundamental problems as to their properties are studied at College Park.

Jan 1, 1941

By R. Hope, C. van Heerden

In any process or organization inefficiencies are costly. In times of abundance this reality often does not receive much attention. During such times the focus is rather on increasing capacity to increase production. However, there is a growing awareness in the world of tougher economic, social as well as environmental conditions, and enterprises find themselves facing greater demands for accountability towards shareholders, the environment and the public, as well as growing competition for market share and limited global resources. This reality is no different in ensuring a sustainable mineral sands operation. In order to achieve this, any operation needs to be stripped of all process as well as operational inefficiencies. In this context it has become essential for any Mineral Separation Plant (MSP) to have the necessary process monitoring and control systems in place to continually monitor and optimize the production of on-spec products and maximize operational efficiency and consistency. The MSP Grade Control Solution developed by Crusader Systems and running on top of the CSense platform contributes towards these goals by improving the consistent production of on-grade product. This allows the process to operate closer to the maximum allowable product grade constraint, which in turn maximizes production.

Jan 1, 2003

By K. Ohto, B. B. Acihikari, H. Kawakita, M. Gurung, S. Alam

Two kinds of adsorbents were prepared from persimmon tannin extract to investigate their adsorption behavior of metal ions from hydrochloric acid solution; one was prepared by treating with concentrated sulfuric acid while another was prepared by immobilizing functional groups of quaternary amine. The former adsorbed only gold(III) and its maximum adsorption capacities was evaluated as high as 1510 g/kg while the latter adsorbed not only gold(III) but also palladium(II) and platinum(IV), the maximum adsorption capacities of which were evaluated as 820, 89 and 101 g/kg, respectively. For both adsorbents, practical adsorption of base metals was not observed.

Jan 1, 2011

By H. R. Babitzke

To develop alloys suitable for use at elevated temperatures, columbium and tantalum were combined with tungsten, hafnium, vanadium, zirconium, and titanium, and the resulting alloys were evaluated with respect to fabricability, hardness, Electrical resistivity, strength at elevated temperatures, oxidation resistance, and bend transition. Of the 23 compositions tested, Cb-2OHf-5W-10Ti exhibited superior high-temperature properties. A recrystallized sample of this alloy was fabricable at room temperature, had a strength of 44,000 psi at 1,200° C, and had an oxidation rate of only 7.7 mg/cm2/hr at 1,000° C.

Jan 1, 1966

By W. Tse, D. Wong

Dense medium separation (DMS) is one of several preconcentration methods used for early waste rejection from run of mine ores at relatively coarse particle sizes prior to additional milling and beneficiation. DMS has been used extensively in the coal, diamond and iron ore industries but lab scale and pilot test work has demonstrated successful separation and upgrading of other minerals such as lead, zinc, copper and lithium based ores using DMS. This paper reviews historical dense media systems, results from the pilot scale Condor DMS system as well as associated laboratory heavy liquid separation (HLS) test work.

Jan 1, 2014

By R. K. Steinhorst

Multivariate cluster analysis, MANOVA, canonical analysis, and discriminant analysis of hydrochemistry data were used to investigate the directions of ground water movement in basalts in the vicinity of the Hanford Reservation, Washington. The statistical analyses indicate that the hydrochemistry of the ground waters in these basalt formations is distinctly different on each side of the Columbia River. This suggests that the river is a ground water divide or that the river is roughly coincident with a hydrogeologic barrier boundary. The statistical procedures used in this study constitute a quantitative means for differentiating ground waters according to hydrochemistry.

Jan 1, 1990

Mercapto organic compound SDMP was used as a depressant for separation of copper activated marmatite from pyrrhotite in the presence of butyl xanthate. Flotation results show that SDMP has strong depressing effect on pyrrhotite recovery in the absence and presence of copper ion, but has promotional effect on marmatite recovery when added together with copper ion. The flotation test of mineral mixtures shows that copper-activated marmatite could be separated efficiently from pyrrhotite using SDMP as depressant. Infrared adsorption spectra demonstrate that SDMP has a strong adsorption on pyrrhotite surface through its functional groups such as ?SH, -S03.

Jan 1, 2006