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By Erwin L. Zodrow

"The neglect of including the toxic metal mercury in the list of escaping elements (Zodrow, CIM Bulletin, September 1982, pp. 138-140) was pointed out to the author in a private letter by J.E. Rehder, dated September 21, 1982. I welcome this opportunity to present my preliminary mercury research data based on coal investigations supported by N.S.E.R.C and the University College.As mercury is a volatile element and liquid at room temperature, special analytical techniques are required to determine concentrations in whole coal. In the investigation, the coal is analyzed by flameless atomic absorption with a lower detection limit of approximately 10 parts per billion, which, however, is a function of the ash contents of the coals (personal communication, J.L. Brooker, XRAL, 1981).Coal seams of the Sydney Coalfield studied so far include: the Point Aconi, a thin shaly coal, the Upper Bonar, an overrider of the Harbour seam, and the Harbour, Shoemaker and McAulay seams, all of which are shown in stratigraphic succession in Figure 1. The seams have been channel-sampled taking 15-cm coal intervals as one sample for analysis. One channel sample has been investigated from each of the seams listed (two channels were taken from the Point Aconi seam), resulting in 38 samples. Table 1 shows the results, which include mercury contents, ash and total sulphur per sample interval. Figure 2 is a frequency distribution of the 38 determinations."

Jan 1, 1982

The recovery by flotation of some complex uranium minerals such as brannerite and davidite is described. Anionic reagents used for flotation of iron and titanium oxides' are suitable. If care is taken, to emulsify the reagents the slime fractions may be satisfactorilytreated.INTRODUCTIONUranium ores are usually treated by direct leaching with acid or alkali according to the nature of the gangue materials. Concentration of the uranium minerals prior to leaching is not commonly practised because of the earthy nature of most uranium minerals and the difficult mineral dressing problem they pose. Some of the harder complex oxides such as davidite and brannerite are amenable to flotation. This is fortunate since they usually require an expensive, strong acid treat~ent to dissolve the uranium. Flotation tests were commenced in 1949 by officers of the South Australian Department of Mines stationed at Adelaide, first in the School of Mines, then in the University of Adelaide and finally in Departmental mineral dressing laboratories at Thebarton. Separation of daviditefrom Radium Hill and Mount Victoria ores, brannerite from Crocker's Well ore, and secondary uranium minerals from Myponga ore was attempted.The development of the flotation reagents to separate the oxides from silica and the silicates is first described, then some of the results obtained are presented as tables.DEVELOPMENT OF FLOTATION REAGENTSThe davidite at Radium Hill is associated with iron and titanium oxides, qu;a,rtz and biotite as replacement deposits in shears. The davidite, rutile,' ilmenite and hematite usually occur in segregations from nut size to masses of several pounds. They are associated as a complexity of...

Jan 1, 1955

By Patrick Scott, Germán Schmeda, Morgan Mullins, Liam Knudsen, Bradley S. Van Gosen, Carma A. San Juan, Nicholas A. Karl, Jeffrey L. Mauk, Clayton Forbush

The objective of the US Geological Survey’s mineral deposit database project (USMIN) is to develop a comprehensive twentyfirst century geospatial database that is the authoritative source of the most important mines, mineral deposits, and mineral districts of the US. Since May 2017, the project has focused on critical minerals. Data for critical minerals that are produced as products are relatively robust, whereas data for critical minerals that may be recovered as byproducts are commonly of much poorer quality. Similarly, more is known about critical minerals that occur in conventional deposits than where those critical minerals occur in unconventional deposits. For example, rare earth elements occur principally in deposits hosted by alkaline igneous rocks, but there is potential for their production from phosphate rock mining, which is less documented. Lithium (Li) has been recovered from pegmatites and brines, but other Li-bearing deposit types have been delineated that may go into production. Cobalt may be produced as a byproduct or coproduct from a wide range ofmineral deposit types, whereas rheniumis a byproduct of copper ore. Significant opportunities for research exist that could help identify new sources of critical minerals, and may also help increase production and recovery from existing sources.

Feb 8, 2021

By C J. Adams, H J. Campbell, A J. Tulloch, I J. Graham

New Zealand can be regarded as a rifted part of mineral-prospective eastern Australia. Geologically credible comparisons between selected trans-Tasman and SW Pacific geological provinces and units, especially those that contain significant mineralisation in Australia, can help provide a useful exploration framework for New Zealand. As part of a six-year Mineral Wealth of NZ and its EEZ (MWE) research programme, we have targeted selected geological units in eastern Australia for comparison and contrast with their potential New Zealand counterparts. In future years, the programme will focus on geological units in New Caledonia.

Jan 1, 2005

By Roger A. Archabal, Omar A. Conte, Gustavo Langoni

This international case study focuses on the rigorous geotechnical interaction and results of a soil improvement program utilized to mitigate consolidation settlements of over 1.5 m [5.0 ft]. The extreme settlement results from very deep, nearly normally consolidated clay and the required high floor loading of a new Logistics Park near Bogota, Colombia. The general subsurface conditions consist of very soft clay extending to depths beyond the 50 m [164.0 ft] explored. A required 1.2 m [3.9 ft] thick fill combined with high floor loads resulted in an applied areal load of approximately 7 ton/m2 [1300 psf] (equivalent to about 4.5m [15.0 ft] of fill). Langan recommended performing a test section to validate the initial consolidation settlement calculations and evaluate possible optimization of the prefabricated vertical drain (PVD) spacing and length. The test section sizing was designed to accurately represent the stresses at depth of the future structures. Extreme settlements of over 1.5 m [5.0 ft] in the center and large differential settlements of over 0.6 m [2.0 ft] were measured between the center and corners of the test section over a relatively short test time. Discussion on the methodology, instrumentation, measured results and future optimization are presented. The recommended soil improvement varied from the standard approaches typically utilized in the area. PROJECT LOCATION AND DESCRIPTION The project site is immediately north-northwest of the city of Bogota in the Bogota Valley. The site is bordered with, and has historically been, farming land bordered to the south by the El Rosal-Bogotá highway. The overall site encompasses about 570,000 m2 [141.0 acres] of gross area and about 484,000 m2 [119.6 acres] of net buildable area. The warehouse complex will consist of 10 very large warehouses with footprints ranging from about 15,000 m2 [3.7 acres] to 30,000 m2 [7.4 acres]. The total building area is about 210,000 m2 [51.9 acres] with most of the remaining areas being paved principal drives, truck parking or administrative parking. The topography of the site is relatively flat and close to final grade in roadway areas. However, the warehouse floors will be raised about 1.2 m [3.9 ft] (equivalent to about 2 t/m2 [370 psf] considering engineered fill) to allow for truck docking. In addition, the design floor loads are heavy and estimated to be up to 5 t/m2 [930 psf] and equivalent to about 2.5m [8.2 ft] of fill. Geotechnical conditions at the site are very weak at depths of 50 meters [165 ft] or more, with soft compressible clays comprising the majority of the soil profile. The Bogota Valley is composed in some areas of very deep alluvial deposits. These deposits have been classified as an important challenge and limitation to the development of high/heavy structures such as the project in question for many years (Orozco, 2006). Soft clay deposits have been encountered even beyond depths of 100 meters [328 ft] in some regions of the Bogota Valley (Sanz, 1994). Extreme settlements can be expected if extensive and high permanent loads (above preconsolidation stress levels) are supported in these thick alluvial deposits.

Jan 1, 2018

According to the previous research, it is found that the thickness of cover is mostly less than 100 m for highwall mining system. However, for most of the Chinese surface coal mines, the mining depth is over 150 m; on the other hand, the shovel-truck is the most common mining technology. As a result, a lot of residual coal will be remained around end-walls. Considering these facts, the calculated methodology of highwall mining system under thick cover is presented in this paper. Meanwhile, numerical simulation of highwall mining system under thick cover was carried out. The outcome shows that the calculated methodology for pillar stability of highwall mining system under thick cover presented in this paper is acceptable. In other words, the highwall mining system is feasible to extract the residual coal around end-walls in Chinese surface coal mines. Thus, not only coal recovery ratio can be improved, but also can increase the production life of surface coal mines in China.

Jan 1, 2012

By D. T. G. Emmett

[ ] South Africa, by a wide margin, is blessed with the largest known world reserves of platinum. The optimal use of these resources for the benefit of all South Africa?s peoples is a goal shared by industry, government and all South Africans. The challenge is to grow the industry in accordance with demand growth and thus to manage a long-term stable growth pattern for PGM usage world-wide. Amplats and the South African producers are well able to meet this challenge [ ] South Africa plays a critical role in the provision of Platinum Group Metals for world markets. In fact no other country has the productive capacity nor the geological reserves to supply the world?s platinum needs. The world required some 5 million ounces of Platinum in 1997 and South Africa supplied a full 74% thereof. The second major supplier, Russia provided a further 18% of world demand, primarily as a by-product of nickel production. Amplats satisfied about 37% of total world demand followed by Impala 20% and Lonhro at 12%.

Jan 1, 1998

By Wynand Erasmus, Terry A. Jones

The Kelsey Centrifugal Jig (KCJ) utilizes the application of centrifugal force (and the resultant enhanced gravitational field) to conventional jigging technology principles to successfully process materials where the valuable constituent particulates are very fine and/or where there is a small specific gravity differential between these and the gangue minerals. The KCJ has been successfully employed in mineral sands applications in Australia for approximately 12 years. More recently, the KCJ has been tested and installed on zircon tailings dump retreatment projects in Australia and the USA, while being considered for similar projects in RSA, and is about to be installed in zircon tailings processing duties in India and Africa and in a tin removal duty in a rutile circuit in Australia. Extensive test work has been carried out on these applications and some typical performance data is presented in this paper. Information is also provided on the principles of operation of the KCJ and on the keys to a successful KCJ installation.

By P. F. Allen

WITH capacity of 51,000 tpd, the Morenci concentrator produces approximately 49,000 tons of tailing for final deposition. Disposal involves distribution of thickened tailing to dams in such a manner that solids can be used for dam construction and water can be impounded for reclamation. During early operation, although tonnage treated was lower, it was necessary to use orthodox disposal practices in the areas available for tailing. Trestles mounted on a series of dams, constructed of borrow material, carried the pipelines from which tailing were spigoted behind the dams. When adequate disposal areas were finally established, it became desirable to look for more efficient methods. The idea of placing the distribution pipe or manifold directly on the crest of the dam was advanced in 1945. After a period of testing, that procedure in modified form replaced the older trestle arrangement. Marked economies resulted, and time required to prepare dams for succeeding storage cycles was greatly reduced. The tailing disposal area for the Morenci concentrator lies south and southwest of the concentrator building. Ample storage space is available. A wide valley contains three sharply defined ravines lying on an average slope of 4 pct. The more central of these ravines, and the largest of the three, is known as Morenci canyon, which provides substantially more tailing storage area than the other two. Stargo canyon lies to the west; the other is appropriately named East canyon. Total area of the tailing disposal site is nearly 31/4 sq miles, or about 2000 acres. The storage area in use was somewhat more than 850 acres at the end of 1954, or 16 acres per 1000 tons of tailing to be stored daily. At the present time none of the east side dams are in regular use but they are available in emergency. There are five dams on the west side (in Morenci and Stargo canyons) as well as two auxiliary dams adjacent to No. 4 West and No. 5 West. This has made it possible to concentrate men and equipment in a smaller area with consequent savings in both manpower and machinery. Tailing Thickening: Tailing from the flotation process reaches the thickeners with a solid content of about 18 pct. The launder carrying this pulp is subdivided at a central point into seven launders carrying a proportional share to each of seven tailing thickeners, which are located in Morenci canyon close to the concentrator. Five of these thickeners are 300 ft diam and two are 325 ft diam. Thickeners are of the peripheral traction type and rakes travel at the rate of one revolution in 37 to 39 min. The entire installation provides 500,000 sq ft of settling area, or approximately 101/2 sq ft per ton of tailing to be thickened daily.

Jan 1, 1957

By E. J. M. Jahnsen, I. Jauhari, T. Badrujaman, F. A. Stober, B. O. Wasmund, L. R. Nelson, T. Miraza, J. M. A. Geldenhuis, A. Taofik Hidyat

The role of dedicated operational support in the ramp-up and stabilisation of the FeNi-II furnace for ferro-nickel production at PT Antam?s smelter located in Pomalaa, Indonesia is described. The furnace was uprated to 32MW capability in a rebuild performed in 2005. This primarily involved installing a larger transformer, coupled with adoption of HATCH water-cooled copper plate, waffle and flanker coolers with integrated metal and slag tapblocks, HATCH air-cooled copper fin lower sidewall cooling and HATCH vertical sidewall binding system ? ?holddowns?. Following a smooth commissioning period, the progress in attaining the preliminary ramp-up target load of 24MW is described. This initial target was set by Antam, subject to some prevailing smelter equipment constraints, particularly kiln capacity. Stabilisation of the furnace operation is discussed, together with some of the specific commissioning and operational challenges surmounted by the joint Antam-HATCH team. These included: ?Mastering furnace integrity monitoring and operation with copper coolers, especially metal tapblock planned maintenance and repair strategies; ?Transition from traditional ?immersed electrode? to ?brush-arc? mode of operation approaching as closely as possible to the productive ?shielded-arc? mode of operation within existing equipment constraints; ?Reductant selection and control issues; ?Utilising the sophisticated furnace monitoring to provide detailed indication and warning of potentially destructive furnace upset conditions such as Si reversion and CO boils.

Jan 1, 2007

By Donald J. Murphy

Longevity of structural units, as compared to the planned useful life of a facility, always is a design consideration. Typical concerns include slow decay due to environmental factors, and changes in constitutive relationships governing the performance of the material involved. With respect to foundations, the usual items of interest are corrosion of steel and concrete, and time dependent behavior of the soil/structure system. For piles, as with other foundations, deterioration is precluded, mitigated or otherwise accounted for by assessing properly the ambient situation (sulphates, pH, stray currents, resistivity) and providing safeguards, such as resistant construction products, oversizing, coatings, and/or cathodic protection. On the other hand, long term performance of the pile foundations, as affected by time dependent characteristics of the supporting soil or rock, can be predicted and controlled only with a synergetic coupling of analyses and field tests. The history of a project for which this approach was followed forms the basis for this paper.

Jan 1, 1986

By Lee T. J

The area, A, under a gamma-ray log that passes through a horizontal bed given by: A = gl/k. Here is the equivalent concentration of U3O8 in the body, l the thickness of the body, and k the calibration factor or sensitivityof the logger. The area is independent of the logging speed or logger time constant.This relationship, together with the first moment about the maximum of the log and its value there suflicient to determine the thickness, position of the centre of the bed from the log maximum and the concentration of U3O8.Numerical results obtained from artificial and field data show that the computed results arc as good as those obtained by methods such as the inverse filter technique and the iterative method. The present method yields results that arc easier to feed into an ore reserve data base.

Jan 1, 1981

By W. V. Long, D. H. Reynolds, R. B. Bhappu

Equilibrium distribution coefficients were determined for some monovalent and polyvalent ions for several absorbing and exchanging media as functions of pH and initial ion concentration. Among ions studied were NH4 (I), K(I), Ni(II), Ce(III), Th(IV), and Mo(VI). Absorbents used were: ion exchange resins; a tertiary, and a quaternary amine in an inert solvent; and some activated carbons. The ions studied were in aqueous HCI, HNO3, H2SO4, or HC104 solutions. The classical mass action expression proved of little value in describing the variations observed. The data indicate that the determining factors in absorption and ion exchange may be the ionic species in the aqueous solution, which in turn depend upon pH, dilution, and perhaps other conditions. Three sorption processes have become prominent in recovering values from leach solutions. These are: 1) ion exchange, 2) solvent extraction (liquid ion exchange), and 3) physical adsorption by materials of high specific surface. In the first two of these processes the exchange reaction is considered chemical in nature, and is discussed in terms of the mass action principle. The third is considered a surface phenomenon and is discussed in terms of surface areas and various forms (Gouy, Stern, Grahame, etc.) of the Helmholtz double-layer theory. Generally speaking, we have found in chemical analysis and hydrometallurgical studies that there are close similarities between the three sorption processes, and also differences which are difficult to reconcile with any of the usual theoretical treatments. That others have experienced the same troubles is shown by the fact that usable processes, in chemical analysis as well as in hydrometallurgy, generally are discovered by empirical procedures. EXPERIMENTAL CONSlDERATlONS The gaps between theory and practice have allowed many conflicting statements to appear in the litera- ture. To learn, in particular, the behavior of some metallic ions on a cation exchange resin at a constant pH, equilibration studies were made over a wide range of concentrations.' Results are shown in Fig. 1 for four metals in hydrochloric acid solution on a strongly acidic cation exchange resin, AG 50W-X8 (Bio-Rad). The distribution coefficient, defined as D = amount of metal extracted per g of resin/amount of metal unextracted per ml of solution is seen to vary in a way to support all manner of reports about its behavior with changes in solution concentration. The metals used were chosen from those least likely to form stable chloro-complexes. The changes of slope in the various isotherms may reflect formation of unsuspected chloro-complexes of low stability (ion-pairing for example) whose concen-

Jan 1, 1967

Research into the mechanisation of ore winning from the very narrow reefs characteristic of South African gold mines has been conducted from as early as 1964 through the Chamber of Mines Research Organisation (COMRO) but with limited success. However, the Council for Scientific and Industrial Research (CSIR) has recently re-evaluated the potential for the mechanisation for the narrow tabular gold mines. It has been determined that there are approximately 22 000 tonnes of gold left in-situ in channel widths of less than 500 mm in thickness. The extraction of ore from such reefs requires a complete paradigm shift in that the current mining cycle (drilling, blasting, cleaning and supporting) is not feasible since such a stoping width would not allow the workers entry into the stope. Consequently, a non-entry form of mining is required. With this target in mind CSIR has invested in a project called the Nederburg Miner which seeks to identify new technologies for drilling, rock breaking, cleaning, and materials handling, the application of which will enable non-entry mining of very narrow ore bodies. The intention is to develop a fully automated system that will not require human involvement at the stope face. The outcomes of research into this proposed system will not only extend the life of South African gold mines but will also enhance South Africa's reputation for excellence in mining research. This paper presents the new technologies under consideration and potential methods for their application into an integrated non-entry mining system.

Jan 1, 2008

By Horst Peter Wölfel

The goal of biodynamic models is to simulate the vibration behaviour of the human body. In combination with experimental studies biodynamical models can be a powerful tool for the analysis of the effects of vibration exposure on health [1] and comfort. This paper gives an overview of the state of the art of biodynamic whole-body vibration models of humans, addressing both numerical models and hardware dummies. Method Two approaches are distinguished, the phenomenological and the anatomical, as illustrated in Figure 1. [ ] Phenomenological models aim to reproduce the vibration behaviour of humans with respect to particular physical quantities, chiefly the driving-point impedance at the interface to the seat, and partly with respect to other transfer functions. Discrete systems of masses, springs, and dampers with several degrees of freedom whose topology and parameters are determined by structure- and parameter identification methods are used in the sense that the functions derived from measurements are reproduced as well as possible. This paper provides an evaluation of this methodology and defines its range of application as well as its limits.

Jan 6, 2006

By Wingham D. W

Based upon the previous work of Norman & Loeb, a method was used to assess the comparative wearing properties of ten different alloys being used, or being considered for use, as mill liners and grinding media at Mount Isa, The materials to be tested were obtained in the form of large diameter balls, and were run, along with the regular ball charge, in a large ball mill operating under normal grinding conditions. At selected intervals, the test balls were removed from the mill, weighed and identified, and their relative wear rates determined.INTRODUCTIONInformation in metallurgical journals, from local iron and steel foundries, and from various metal promotional organizations has suggested that the various alloy compositions available should be examined and assessed for possible use as milllfners and grinding media.Previous attempts at evaluation of recommended materials for these applications elsewhere, have usually involved the purchase of large quantities of grinding balls or complete mill liner sets, requiring running periods of up to two years or more. As well as being both a costly and lengthy procedure, the information obtained may be of little significance, due to changes in milling practice, and ore characteristics during the period of operation.To overcome these difficuities, a method was adopted based on the short time wear rate test recommended by Norman & Loeb (1949) and Norman (1957) in which all the materialsunder consideration are ·subjected·concurrently to the conditions of service.Previous calculations of wear rates have been dependent1. Senior Metallurgist (Materials), Mount Isa Mines Limited.2. Metallographer, Mount Isa Mines Limited.Manuscript received at The Institute, 22nd April, 1963, and presented to the1963 Annual Conference.

Jan 1, 1963

By B. H. Kim

It is hypothesized that the standard approach adopted to characterize the ground and to determine the rock strength properties at depth are flawed and generally tend to underestimate the rock strength and possibly the stiffness, particularly when the rock mass is characterized as massive to moderately jointed or blocky to very blocky. It is therefore necessary to conclusively established that the hypothesis, that the rock strength in highly confined rocks is greater than generally anticipated, is actually valid and generally applicable, and then to develop new procedures to establish rock parameters that can be reliably used for the design of deep excavation.

May 1, 2009

By Alan Galley

CMIC Mandate CIM Annual Meeting, Toronto, May 6, 2013 To increase mining research, innovation and commercialization efforts in order to strengthen Canada?s pre-eminent role as a global leader in mineral exploration, mining and knowledge-based services and technologies. To increase the supply of highly qualified graduates from mining and earth sciences faculties to meet the significant demand today and into the future of industry, governments and academia. The CMIC initiative is intended to develop long term research strategies that extend five or greater years. Such a research plan will underpin fundamental research and innovation and the training of HQP

May 1, 2013

By Jaeheon Lee, Junmo Ahn, Jiajia Wu

In this project, low grade copper ore samples were obtained from two mining sites in the US, and they were chalcopyrite-rich (sample A) and conichalcite-rich (sample B) ore. Copper grades were 0.6% and 0.4% for the two samples, A and B, respectively. Leaching experiments were conducted by bottle roll tests for 24 hours, and various lixiviant systems were applied. Methanesulfonic acid (MSA) and glycine were used as alternative lixiviants to sulfuric acid. Oxidants including ferric ion and hydrogen peroxide were tested. The results showed the copper extraction of sample A increased after adding 1 g/L ferric ion in sulfuric acid and MSA solution, from 20% to 36%, but further increase was not observed with higher ferric ion concentration. The copper recovery increased significantly with H2O2 concentration, and over 80% copper recovery was obtained with 10% H2O2. For sample B, the copper dissolution kinetics were relatively fast and reached the maximum value in five hours. Around 60% copper were extracted in sulfuric acid and MSA solution. Copper recovery slightly increased after adding ferric ion and H2O2. Glycine is a weaker lixiviant for both samples, the copper extractions were 36% and 4% respectively. INTRODUCTION Chalcopyrite is the most abundant copper sulfide mineral on earth, and it is one of the most refractory copper minerals regarding chemical processing. The declining copper grade and depletion of copper oxide deposits stimulate the development of hydrometallurgical process to extract copper from chalcopyrite. The dissolution of chalcopyrite by ferric ion is normally illustrated as Equation (1) and (2) (Dutrizac & MacDonald, 1974): CuFeS2 + 4Fe3+ → Cu2+ + 5Fe2+ + 2S0 (1) CuFeS2 + 4Fe3+ + 3O2 + 2H2O → Cu2+ + 5Fe2+ + 2H2SO4 (2) However, slow kinetics are usually observed from chalcopyrite leaching at ambient temperature and pressure. Researchers attribute the slow kinetics to passivation during chalcopyrite dissolution, and different passivation products are also proposed (Klauber, 2008). In recent years, many efforts have made to develop new methods to extract copper from chalcopyrite, such as utilizing bacteria or stronger oxidant (Zhao et al., 2015; Ruiz-Sánchez & Lapidus, 2017).

Jan 1, 2019

By Steve Kral

For a state whose roots are in mining, most Colorado residents probably do not realize that the industry still contributes heavily to the state’s economy. In 2005, the industry contributed, directly and indirectly, about $8 billion to the state’s economy, according to the Colorado Mining Association (CMA). It employed nearly 10,000 people at mines and support businesses. And the mining industry in Colorado is one of the highest paying occupations in the state, averaging about $80,000 a year in wages and benefits. The state’s coal mining industry produced nearly 36 Mt (40 million st) of coal in 2005, valued at $800 million, the CMA said. That was seventh in the nation. And Colorado’s only major gold mine produced 10.2 t (329,000 oz) last year, valued at $124 million. That was third in the nation. And Phelps Dodge’s Henderson Mine produced about 12.7 kt (28 million lbs) of molybdenum, valued at $350 million. Colorado is the largest molybdenum producing state in the nation.

Jan 1, 2006