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By Neri Roux, Chris Budgell, Allan Cramm, Leo Cheung

"Anaconda Mining Inc. is investigating potential improvements and expansions to their operating plant located on the Baie Verte Peninsula in Newfoundland. An extensive batch and continuous bench scale testing program was launched to investigate the efficiency of cyanide destruction under different conditions in order to improve tailings handling. The primary objective of the cyanide destruction study was to apply new technologies to develop a novel cyanide destruction system.Effluent and slurry from Anaconda Mining Inc.’s Point Rousse Project was received at RPC where test work was conducted. Various sodium metabisulfite (MBS) dosages were evaluated and the use of utilizing ozone and ultra violet (UV) light to oxidize cyanide was investigated. All the data was evaluated and mass balances were compiled to develop several flowsheets. Overall encouraging results were found using a combination of ozone and MBS.IntroductionAnaconda Mining Inc.’s Point Rousse project includes an operating gold processing plant located on the Baie Verte Peninsula in Newfoundland which is in the process of improving and expanding. This plant comprises of milling and flotation followed by cyanide leaching in order to extract the gold. The residue from cyanide leaching is filtered by drum filters prior to being clarified for the Merrill-Crowe process. Once the gold has been recovered by the Merrill-Crowe process the effluent is filtered by filter presses and the resulting filtrate as well as the solids from the drum filters are detoxified prior to being pumped to the tailings pond along with the flotation tailings.The entire process is very dependent upon the efficient destruction of cyanide in the effluents and successful tailings handling. Substantial amounts of effluent are delivered to tailings ponds after gold extraction which could create environmental problems if the regulations are not met. Environmental regulations stipulate that final effluents contain no more than 1 mg/L Total CN.The detoxified tailings of the Point Rousse project are produced by the INCO SO2-Air circuit depicted in Figure 1. These detox tailings contain 10 mg/L Total CN at that point of the circuit and this was selected as the target to be matched while reducing overall MBS consumption rates from 3.2 g/L per minute. Prior to detoxification, the filter press tailings contain 520 mg/L Total CN while the drum tailings contain 29 mg/L Total CN."

Jan 1, 2017

Upgrading of a Flow Sheet Selection PC Algorithm for Refractory Concentrates Treatment

Sep 13, 2010

By A Kamkar-Rouhani

The paper describes a mineral potential mapping of gold and other base metals in Mahneshan area, Iran, using geographical information system (GIS), in which, the method of weights of evidence is used to combine spatial data obtained from different sources to make prediction for mineral potential. This is a quantitative tool for mineral resource mapping that can be used to delineate and predict favorable areas for further exploration by using the characteristics of known and similar mineral deposits. In accord with the descriptive model for gold and other base metal deposits, the spatial distribution of 20 known mineral occurrences was used. In addition, digital evidential maps were used in this study. The maps include maps of lithological units, faults and first derivative of total aeromagnetic data, remotely-sensing data of alteration and also geochemical evidential maps produced on the basis of the results of chemical analyses of samples taken from the stream sediments in the area, and analysed for Cu, Pb, Zn, Sb, As, Ag, Au, Ba and Hg elements. The binary maps were produced and then combined with the model of weights of evidence using 20 known mineral occurrences to obtain a final map of the favourable areas for further exploration of gold and other base metals in the study area. The final map is a predictive GIS model of the mineral deposits in the area. An interesting matter about the final predictive GIS model is that the faults are mainly located in favorable areas which possesses the most probability of mineralisation. Therefore, the faults in these areas have priority for further exploration of gold and others base metals.

Jan 1, 2005

By Michael K. Watkeys, Charlesworth. E. GUY, Jacobus E. Potgieter, Anhaeusser. Carl R., Roger L. Gibson, Alexander F. M. Kisters

Abstract - Intrusive features of cupriferous noritoids from the deeply eroded Proterozoic granite-gneiss terrane of the Okiep Copper District in South Africa illustrate the emplacement of basic magmas into a mid- to lower-crustal environment. The small, easterly trending intermediate to basic intrusions of the so-called Koperberg Suite display a wide variety of geometries, occurrence and emplacement modes, including dike-, sill- and plug-like bodies. Coeval granulite-facies metamorphism, partial melting and ductile deformation of country rock gneisses during intrusion of the basic magmas led to emplacement and dilation processes of the intrusions which differ significantly from those described for dikes and sills at shallow crustal levels. Regional tectonic stresses are largely negligible due to very low differential stress (?1 - ?3) during deformation and intrusion, which permits emplacement at high angles to the principal compressive stress and which follows favorably inclined structural anisotropies. Dilation of the basic intrusions is largely determined by compositional differences of host rocks and occurs by thermal erosion, i.e., assimilation of wall rock gneisses. Low length-to-width ratios of basic to ultrabasic dikes and predominantly diaper -like outlines of mesocratic bodies are indicative of low viscosity contrasts between the mafic magmas and high-grade metamorphic host-rock gneisses. Buoyancy-controlled ascent of the basic to intermediate intrusions is expressed by a broad compositional zoning of basic bodies with respect to the granite-gneiss stratigraphy. Various intrusion modes within the stratigraphic column of the granite-gneiss sequence reflect a lithological and structural stratification of the seemingly homogeneous granite-gneiss terrane.

Jan 1, 1994

By Delahant A. B, Dworski M

From the Saranac Laboratory for the Study of Tuberculosis of the Edward L., Trudeau Foundation, Saranac Lake, New York:We are assembled to honor the memory of our friend and colleague, Donald Cummings, one of the founders and a past president of the American Industrial Hygiene Association. I deem it an Unusual privilege to have been asked to give this first memorial lecture and hope that what shall have to say may be worthy of the occasion. It is fitting that we should discuss here the subject of Silicosis to which he devoted such a large part of his life and it is doubly fitting, I think, that I should report to you an extended series of investigations carried on by his associates at the Saranac Laboratory.The subject of silicosis may seem hackneyed to this audience which is so familiar with the tried and accepted methods of prevention and control.But in spite of our efforts, the condition is still with us and unfortunately is still being produced in many places. In industries that now maintain good control of dust, fresh cases are appearing on annual re-examination, whose major exposure date back to the days before the hazard was recognized.A few new employees, with apparently ineffective upper respiratory protection against inhaled dust, develop silicosis precociously in environments that are comparatively harmless to their fellows. In plants that have relaxed their vigilance under the urgency of war production schedules, conditions again prevail that will produce, disease in the future.Silicosis acquired new interest with the announcement by Denny, Robson and Irwin(1) in 1937 that it could be prevented by the inhalation of powdered metallic aluminium. It so happened that without knowledge of their work, we at the Saranac Laboratory had for some months been conducting similar experiments with one of the hydroxides of aluminium.Quite independently we discovered that hydrated alumina would also protect animals against quartz. Our approach to the problem had been empirical; we were trying to neutralize quartz particles by coating their surfaces with an insoluble material following the lead of Kettle who in 1932 had shown that this could be accomplished with iron. He neglected to describe his method and the chemist who prepared his coated...

Jan 1, 1945

The uphole bench extraction strategy at EKJV Management Pty Ltd?s Raleigh Mine, requires simultaneous horizontal and vertical exposure of paste filled stopes. In order to prevent excessive ore dilution, the paste fill must be of sufficient strength to prevent failure during exposure. A numerical modelling methodology has been developed to accurately simulate the initial stress distribution within paste filled stopes, together with the strain-softening loading response of paste fill material. Due to the narrow orebody width and high deformation behaviour of the host rock mass, high closure strains are likely to cause a stiff, brittle fill material to undergo crushing failure upon exposure. The stability of paste fill exposures at the Raleigh Mine was determined by conducting a series of three-dimensional numerical models that incorporate the extraction, filling and exposure sequence of paste filled stopes. Stability charts for 2.5 m and 3.5 m wide simultaneous horizontal and vertical exposures have been derived based upon the numerical modelling results. Implementation of the stability charts has proved successful in limiting the amount of ore dilution from paste fill and provides a basis to optimize paste fill cementation and stability throughout the life of the mine.

May 1, 2007

By M. B. Boyer, C. H. Herty, F. A. Hartgen, G. L. Frear

"DEFINITION OF VISCOSITYViscosity has been defined as the resistance experienced by one portion of a liquid moving over another portion, such as one molecular plane moving over an adjacent plane. A measure of viscosity is the force required to keep one plane in motion at Unit velocity, the other plane being considered stationary. Figure 1 illustrates the general idea that the surface friction between two adjacent areas will be greater the larger the molecules. Therefore it may be assumed that viscosity will be increased by molecular association or agglomeration, and likewise dissociation rill decrease viscosity. According to Maxwell (1)6 the unit of viscosity, the poise, is the tangential force per square centimeter of area of either of two horizontal planes 1 centimeter apart, one of which is fixed while the other moves with unit velocity, the space between being filled with viscous liquid of unit viscosity.The need for a satisfactory apparatus and experimental procedure for the determination of viscosity of high-melting materials at temperatures corresponding to those in pig-iron and steel making has been recognized during the past few decades. The condition of the slag during the smelting and refining periods in the iron- and steel-making processes exerts an important influence on the metal product obtained, this slag condition really meaning the state of viscosity or, vice versa, fluidity, which the slag attains under certain conditions."

Jun 1, 1934

By Mark Sanders

This report compares a proposed 10/60 "piggyback" 02 generating self-rescue unit to the standard CO self-rescue unit with respect to work task interference. A simulated low seam coal mine was constructed and subjects performed locomotion, shoveling, cart pushing, and timbering tasks with the 10/60 or self-rescuer attached to their belts. Task completion time was longer on all tasks when wearing the 10/60 unit, although only locomotion was statistically significant. The 10/60 unit was bumped over 100% more often than the standard self-rescuer. Implications for design of the proposed 10/60 container are: 1) unit?s container must be extra durable to withstand the added abuse it is likely to receive by low coal miners; and 2) extra consideration must be given to preventing the device from slipping on the belt while working, especially in low coal.

Jan 1, 1980

By Peter L. McSwiggen

The mineralogy of the Biwabik Iron Formation changes dramatically from west to east as the formation nears the basal contact of the Duluth Complex. This reflects a contact metamorphism that took place with the emplacement of the igneous Duluth Complex at tem¬peratures as high as 1200 °C. However, the mineralogy of the Biwabik Iron Formation also varies vertically through the stratigraphy of the unit. This variability in both the vertical and horizontal dimensions makes it difficult to predict exact horizons where specific minerals will occur. The iron-formation has been subdivided into four broad stratigraphic units (lower cherty, lower slaty, upper cherty, and upper slaty) and into four lateral mineralogical zones (1-4). Zone 1, the westernmost zone, is characterized by quartz, magnetite, hematite, carbonates, talc, chamosite, greenalite, minnesotaite, and stilpnomelane. The silicate mineralogy in Zone 2 of the Biwabik Iron Forma¬tion changes very little. However, the minerals begin to change dramatically in Zone 3. Most significantly, Zone 3 is characterized by the appearance of grunerite in both a tabular form and a fibrous form. In Zone 4, the original silicate minerals have completely reacted, and a new suite of minerals occupies the iron-formation. These include grunerite, hornblende, hedenbergite, ferrohypersthene (ferrosilite), and fayalite.

Jan 1, 2007

By David B. Paul

"ABSTRACTThe US Army Corps of Engineers (USACE) has 704 dams in their inventory and over 100,000 miles of levees with a capital value of over $150 billion. Currently, there are 319 dams that are classified as high hazard and have actionable failure modes that will require structural modifications. The most frequent actionable failure mode associated with the inventory is seepage and piping. One of the most effective engineering solutions is the installation of a cutoff to limit seepage. Currently, USACE has over $1.5 Billion of cutoff wall projects under construction and/or design. Given the magnitude of the dam and levee safety issues, USACE is developing a new Engineering Manual (EM) titled “Seepage Control Cutoffs for Dams and Levees.” This EM covers all of the methods to construct cutoff walls. USACE has partnered with the Deep Foundation Institute (DFI) in preparation of the EM to ensure that it is comprehensive and draws from the expertise of the specialty foundation engineering companies that design, manufacture, and construct seepage control cutoffs around the world. The EM contains case histories as well as a comprehensive project statistical summary and guide specification paragraphs. The goal of USACE was to make the EM a state of the art document for use by Districts.HISTORYSlurry wall construction techniques were developed in the late 1940’s in Italy by ICOS. The first use of the slurry trench method of construction in the United States was by the USACE Memphis District in September 1945, to form a partial cutoff along the Mississippi River levee on the Arkansas side of the river just below Memphis, Tennessee. The idea for the project probably evolved from the use at that time of puddle clay trench cutoffs combined with the use of drilling mud for advancing borings. A paddle wheel mixing device was constructed for making slurry from native clays. Trenches were dug to a 20-ft depth using a trenching machine and to a 35-ft depth using a dragline with a 100-ft boom and 2-cu-yd bucket. Backfill was mixed in windrows at the site from hauled-in clay gravel and native materials and pushed into the trench by a bulldozer when the length of the trench was equal to about twice the trench depth. It is amazing that after almost 70 years, the technique is still about the same as it was when first developed by the Memphis District. A soilbentonite cutoff was constructed under the Kennewick Levee adjacent to the Columbia River as part of the McNary Dam Project in Washington by the Walla Walla District in 1952 The first application of a soil-bentonite slurry trench cutoff for control of underseepage at a major earth dam was at Wanapum Dam on the Columbia River in Washington in 1959.The first cement- bentonite cutoff in the United States was constructed at the Tilden Tailings Project to store tailings from the Tilden Mine in Michigan in 1976. The first cement-bentonite cutoff constructed at a dam on a river retaining a reservoir in the United States was completed in 1978 at the Elgo Dam (formerly the San Carlos Dam) in Arizona.The USACE has designed and constructed some of the deepest and most complex cutoff walls for dams since the 1970’s. The first major concrete panel cutoff wall constructed in a dam in the United States was at Wolf Creek Dam (Nashville District) by the ICOS Corporation between 1974-77. The dam has a long history of seepage issues associated with the karst geology that comprises the foundation. In 1968, about 17 years after first being impounded, wet areas, muddy flows in the tailrace and sinkholes in the downstream toe adjacent to the switchyard occurred."

Jan 1, 2014

By Peter L. McSwiggen

The mineralogy of the Biwabik Iron Formation changes dramatically from west to east as the formation nears the basal contact of the Duluth Complex. This reflects a contact metamorphism that took place with the emplacement of the igneous Duluth Complex at temperatures as high as 1200 °C. However, the mineralogy of the Biwabik Iron Formation also varies vertically through the stratigraphy of the unit. This variability in both the vertical and horizontal dimensions makes it difficult to predict exact horizons where specific minerals will occur. The iron-formation has been subdivided into four broad stratigraphic units (lower cherty, lower slaty, upper cherty, and upper slaty) and into four lateral mineralogical zones (1-4). Zone 1, the westernmost zone, is characterized by quartz, magnetite, hematite, carbonates, talc, chamosite, greenalite, minnesotaite, and stilpnomelane. The silicate mineralogy in Zone 2 of the Biwabik Iron Formation changes very little. However, the minerals begin to change dramatically in Zone 3. Most significantly, Zone 3 is characterized by the appearance of grunerite in both a tabular form and a fibrous form. In Zone 4, the original silicate minerals have completely reacted, and a new suite of minerals occupies the iron-formation. These include grunerite, hornblende, hedenbergite, ferrohypersthene (ferrosilite), and fayalite. © 2007 Elsevier Inc. All rights reserved. Keywords: Biwabik Iron Formation; Duluth Complex; Mineralogy

Jan 1, 2007

By C. G. Cheriton

The Bathurst mining district is located near the town of Bathurst on the north shore of the province of New Brunswick in eastern Canada. This region is the northeasterly extension of the Appalachian mountain system. The area is heavily forested and covered with a fairly uniform layer of glacial gravels and boulder clay. The relief is low, increasing to a few hundred feet in the north west and several hundred feet in the extreme southwest. Thus, rock outcrops are scarce and occur mostly along streams and ridges. These factors made conventional prospecting difficult and resulted in the district becoming an excellent place for the application of regional geological studies, air photo techniques, airborne and gound geophysical methods and soil sampling. Late in 1952, The Brunswick Mining and Smelting Company discovered a very large base metal sulphide body presently known as their No. 6 orebody. Early in 1953, another and even larger sulphide body was discovered and is known as the No. 12 ore body. Mining exploration was very active thoughout 1953 and in 1954, The American Metal Company discovered the orebodies which have been developed into The Heath Steele 'Mines. The location of these deposits is shown on figure one. In the latter part of 1954, The Anaconda Company became interested in the district and decided to make a geological study of this new and promising base rrietal area. The following paper presents the story of the application of modern geological and geophysical techniques, leading to the discovery of a large sul-nhidp liodv. The Bathurst district is generally underlain by the Tetagouche group of Middle Ordovician rocks.

Jan 1, 1961

Radioisotope x-ray and neutron techniques of analysis can be used for the determination of a wide range of elements in minerals. The most important applications of these techniques to the mineral industry are for onstream analysis of slurries and solids, and for geological assay.The radioisotope x-ray techniques are the more developed ones and two installations for on-stream analysis are in routine use in mineral processing plants in Australia. Neutron techniques are being developed, and should prove valuable for geological assay of large numbers of mineral samples, for borehole logging, and for specific on-stream analysis when the cost of the equipment is warranted.

Jan 1, 1970

The need to hoist increasing loads from great depths is leading to the more general adoption of winders of the Koepe and Blair types. The trend has introduced a number of new problems in winding ropes, more particularly in the Koepe system where regular destructive tests during the life of a rope are not possible. Consequently, the importance of introducing non-destructive tests is much greater, especially so in the case of Koepe ropes used for deep winding where there are three major destructive fatiguing influences. These are rotational effects when a vertical rope is changed end-for- end each trip, the much greater range of stress to which the rope is subjected each trip as compared with drum winding, and the destructive effect of a high coefficient of friction between wheel and rope. A plea for a lower coefficient in the interest of better rope and tread life, substantiated by analysis, is made for Koepe winders operating at depth.Co-ordination of rope testing with general hoisting problems is stressed and the active participation of the Wire Rope Committee of the Australian Mineral Industries Research Association Ltd. in the promotion ofthe project is noted.The general introduction of a rope testing programme in Australia, personnel requirements and some local basic research in the subject to cope with future demands are considered.

Jan 1, 1967

By A McDowell

Pound Road Quarry is an alluvial gravel quarry owned and operated by Fulton Hogan Ltd. for the supply of aggregate in Canterbury, and is the largest quarry in the South Island in terms of production. It has evolved from three separate quarries, as a result of which extraction has occurred sporadically in a number of areas. Due to this factor, and the need to manage environmental impacts, a detailed quarry management plan was completed in 1995 which formed the basis for implementation of a certified environmental management system.   In December 1997, the quarry was the first in New Zealand to achieve ISO 14001 (TELARC) accreditation for implementation of an environmental management system. The main potential environmental impacts arising from the quarry operation include dust, noise and groundwater contamination, and visual landscape effects associated with gravel extraction, the mitigation of which is achieved by means of æbest practiceÆ methods. All quarry operations are controlled in terms of the environmental management system by means of regular (monthly and yearly) environmental reviews, appropriate auditing of environmental documents, and monitoring of environmental targets in accordance with consent and statutory requirements.

Jan 1, 1998

By B. A. Day

The traditional view taken of commodity prices is that they are cyclical, with strong demand boosting prices and attracting new suppliers. The resulting increased supply pushes prices down with consequent exit of the higher cost producers. And so the process repeats itself. Little attention is given to shifts in underlying global issues and their effect on the traditional process which is seen as being controlled by ?amorphous? market forces with producers profiting from the good times and trying to survive in the bad.. The questions posed are: does this still apply and will it apply into the future? What new factors are affecting the cycles? Can we expect to find the traditional commodity cycles repeated in the 21stcentury? Are producers powerless within the forces of the cycles? Forces likely to affect future commodity prices will be suggested, using gold, zinc, copper, tin and coal as case studies. The long-term downward trend in the real price of commodities is identified.

Jan 1, 2000

By G. J. de Korte

South Africa’s best-quality coal, located in the central Highveld basin, is becoming depleted and alternative sources of coal, such as the Waterberg coalfield, will have to be developed to supply the country with coal in the future. The quality of the coal being mined in the central basin is gradually becoming poorer. This necessitates that more of the coal be processed to improve the quality to meet customer requirements. The challenge to the coal processing industry is to process low-yielding coals to produce goodquality products and at the same time ensure that coal mining remains economically viable. This requires that more cost-effective coal processing technologies be investigated and implemented.

Jan 1, 2015

The Tasman Orogenic Zone is regarded as a single metallogenic province (the Tasman Province) with four SUb-provinces corresponding with its major tectonic components: the Lachlan, New England, Hodgkinson.and North Queensland orogenic provinces. Within the Tasman Province there are four main ore-rock associations.These are1. manganese and iron with sedimentary and basic volcanic rocks,2. zinc-lead-copper and copper with intermediate-acid volcanic sequences,3. minor chromium, platinum, and osmiridium with ultramafic complexes, and4. tin, wolfram, gold, and copper with syn- and posttectonic granitic intrusions.Whereas the ores of ultramafic and volcanic associations form geographically-restricted metallogenic districts, the ubiquitous granitic ores may be subdivided into twenty-one districts that cover almost the entireOrogenic Zone. The Tasman Province is notably lacking in uranium ores and Mississippi Valley-type deposits.There is a distinct tendency for ores of each association to be progressively younger to the east and north, thus paralleling the progressive growth and stabilization of the Zone. Similar ore-rock associations are present in repeated phases of mineralization from the Cambrian to the Permian-Triassic, reflecting the essential homogeneity of the Tasman Province, and the similarity of the successive tectonic cycles.

Jan 1, 1972

By D. A. Buckingham

Engineering and economic evaluations were performed by the Bureau of Mines on 14 Frasch sulfur, 1 native sulfur, and 21 metal sulfide operations in 11 market economy countries. The evaluation included discounted-cash-flow rate-of-return economic analyses at 15 pct to determine the average total cost of production of these two commodities and the potential availability of elemental sulfur (8) and pyrite concentrate. The Bureau evaluated the potential availability of elemental sulfur and pyrite concentrate. Approximately 279 million metric tons (Mmt) of pyrite concentrate at 46 pct 8 is potentially recoverable from 422 Mmt of in situ metal sulfide ore. Nearly 89 pct of the total pyrite concentrate is available at an average total cost of production below the January 1984 pyrite concentrate market price ($43/mt). About 185 Mmt 8 is potentially recoverable from 253 Mmt of in situ elemental sulfur. About 99 pct of this sulfur is available at an average total cost of production below its January 1984 market price ($131/mt).

Jan 1, 1986

By R Hardie, J Crerar, J Merritt, B Kirsch

Longwall mining and related subsidence, and watercourse diversion for surface mining operations have the potential to impact on fluvial geomorphic processes and the health of river systems. This is evident in the Isaac River in central Queensland. The scale and likelihood of these impacts are a function of the extent of existing and proposed mining developments and of the ongoing geomorphic, hydrologic and ecological processes within the Isaac River. Understanding the objectives for the river, the past and ongoing processes at work, the cumulative impacts of longwall mining development and the options for managing those impacts is essential for the development of an effective strategy to manage the health of the river system. An assessment has been undertaken to identify and understand the cumulative impacts of mining subsidence and other mining influences on geomorphic processes and waterway health in the Isaac River over a river length of approximately 100 km near Moranbah in central Queensland. The assessment included the development of a vision and objectives for waterway health. The assessment has identified mining and landuse changes that have impacted on the hydrology, geomorphology, ecology and hence the health of the Isaac River. The assessment has then sought to identify the cumulative impact of longwall mining and related subsidence on current stream condition and the proposed vision for the system. The primary impact of longwall mining on the river was found to be associated with sediment transport. The investigation included assess- ment of total sand available for transport, the volume of sand transported annually and the fluvial process response to subsidence. Recommendations have been developed for the management of the system and for longwall mining to increase system robustness and achieve the river health objectives.

Jan 1, 2009