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By L. R. Verney

About 75% of the market economy countries's supply of cobalt is produced in Central Africa by Zafre and Zambia. Zafre alone accounts for more than 55% and has the resources and capacity to increase output significantly at any time so its dominant position is unlikely to be challenged in the foreseeable future. Other producers from domestic resources are Canada, Australia and South Africa; and Cuba, probably the most important producer outside of the Market Economy countries. Belgium, Norway, France, Japan and Finland produce cobalt from imported materials. While there are "cobalt ores", inMorocco, USA, Canada and the USSR, the mineralisation is complex and cobalt extraction is costly. In ZaPre and Zambia cobalt is a by-product of copper; in Canada, Australia, France, and Cuba it is a by-product of nickel; and in South Africa it is a by-product from the production of Platinum Group Metals. Thus the levels of cobalt production are inevitably related to the production of other primary metals. While some cobalt is produced by predominantly pyrometallurgical methods most of the world's cobalt is produced hydrometallurgically. The existence of large hydro-electric power plants and the mineralogy of the copper and cobalt concentrates encouraged research and development in Zafre of the recovery of copper and cobalt by electrowinning from sulfate solutions; much pioneering work was carried out, which lead to construction of the two largest copperlcobalt hydrometallurgical plants in the world, at Shituru and Luilu. Similar systems were adopted in Zambia. In Canada high pressure hydrometallurgical processes based on the sulfate system were developed and adopted in Australia, the Philippines, Finland and South Africa. Meanwhile developments in chloride hydrometallurgical extraction of nickel and cobalt lead to its use in the extraction of cobalt in Norway, France and Japan.

Jan 1, 1988

By Maggi Loubser

"In a technologically advanced era, where process control is accurately maintained within the smallest error margins, and accuracy and precision are continuously improved, sampling is still left to the lowest paid employee in the company without training him or her properly to understand the relevance and importance of the task. In this paper the objectives of sampling in a process control environment is discussed and an attempt is made to link it to the theory of sampling. Some of the practical problems associated with implementing theoretical sampling principles in an industrial environment will be elucidated and some examples given on how compromises are made. Different methods of sampling will be discussed with real life examples from different manufacturing industries."

Jan 1, 2014

By K. T. Cunningham

The Oakfield, New York Hine of the United States Gypsum Company is a shallow, room and pillar mine developed in the Camillus Formation of Silurian Age on the up-dip edge of the northern Appalachian Basin. The gypsum comes to subcrop beneath a variety of glacial materials and is subject to solution activity by groundwater. A geologic environment unfavorable to mining activity is thus created. Since 1978 seismic studies have been used to supplement core drilling to determine a conservative boundary between normal and questionable mining environments. A single channel seismograph, originally in use, is now replaced by a twelve-channel unit and is used to determine bulk material velocity which is the basis for defining the mining limit.

Jan 1, 1987

The relationship between the aspect ratio and physical fields in aluminium reduction cells wase studied numerically. The aspect ratio was firstly defined and 7 kinds of 320 kA cells with different aspect ratios were put forward. By using numerical simulation, the relationship between the aspect ratio and the electric-magnetic flow fields, magnetohydrodynamic stabilities, and thermal stability was discussed. It is concluded that the electric-magnetic flow field distributions are greatly affected by the aspect ratio. From the perspective of magnetohydrodynamics stability, the larger the aspect ratio is, the more stable the cell will be. A larger aspect ratio is more beneficial for the thermal stability under the same current density.

Jan 1, 2011

By Charles E. Whieldon

The importance of producing more oil from known petroleum reserves has placed increased emphasis on the application of secondary-recovery methods. Recently published reports3 4/ describe the results of waterflooding in Roane and Pleasants Counties, W. Va. (see fig. 1.) This report describes the Barron Kidd Oil Co.?s Santee waterflood project, Maxton sand, Burton field, Church district, Wetzel County, W. Va. (See fig. 2.) The Federal Bureau of Mines hopes that these reports will stimulate interest in improved waterflooding techniques, thereby discouraging premature abandonment of oil leases.

Jan 1, 1961

By D. A. Dahlstrom

Since the initiation of continuous vacuum filtration over a half a century ago, control of the performance of these units has been largely in the hands of the plant operators, Obviously there has been the introduction of variable speed drives, adjustable speed feed slurry agitation, vacuum control, etc. However, control of , filtration rate, cake moisture content, dissolved solids recovery by cake washing and dryness of solids where thermal drying is practiced is primarily up to the operators judgment and the settings he imposes on the controls he regulates, - filter cycle time, submergence, vacuum level, filter medium condition, wash water- rate, and other such factors. While this may seem to indicate that good operators are a paramount necessity, and certainly always desirable, a considerably more vital factor is a properly designed filter and filter station for the particular application. With improper design, highly skilled operator control will still leave much to be desired in the way of process performance. On the other hand, with correct design and application, the operator can easily and quickly control normal plant surges and quality variations within the flow sheet. Due to the growing complexity and inter dependency between the various processing steps in the modern flow sheet as well as the rising costs of capital investment, labor, maintenance, and losses involved with off quality product or insufficient recovery, automatic or inherent performance control of many of the unit operations within the metallurgical mill must be achieved. Continuous filtration should and can be susceptible to such control. However, as every instrument engineer knows, before control and automation can be achieved, a basic understanding of the operation is mandatory. This is primarily due to three factors. First, as in so many control applications, it may not be possible or feasible to measure the factor that it is desired to control. Thus, secondary variables that influence the major factor are substituted for control purposes. Secondly, it is always desirable to take advantage of any ?self-regulation? within the operation being performed on the equipment. In so doing, not only will automatic control be facilitated, but instrumentation is minimized while experiencing most efficient operation. Finally, automatic control is not a cure-all for improper process and equipment design and application. Hanging instruments on such an operation can be compared to constructing a sizable building on sand, Results will be disappointing.

Jan 1, 1960

By D. R. Mitchell

This paper discusses some of the fundamental physical and chemical characteristics of coal in Illinois that affect its preparation for the market. At the present time preparation consists almost entirely of sizing and hand-picking. The washing of coal has almost entirely disappeared from the state. This is a rather startling fact when one considers that in the year 1908 Illinois outranked all other states in the quantity of coal washed and a few years later, in 1912, 85 washing plants were reported. Two reasons are apparent for this change. One, which is probably the most important, is that immense areas of comparatively clean coal were opened; the other is that many of the early washing plants were inefficient, so that washed coal was looked upon with disfavor in many trade centers. Objectives of Operators Some of the outstanding preparation aims being given due consideration by operating men are: 1. The greatest possible production of lump and domestic sizes which bring in the market at least $1 per ton more than the fine sizes or screenings. 2. Efficient screen sizing with as little breakage as is consistent with economical operation. 3. The removal of extraneous ash and sulfur. 4. Utilization of low-priced screenings. 5. Suppression of dust in domestic coal shipments. Preparation Underground To get the greatest possible production of the larger sizes, preparation must start at the face. Improvements in blasting and loading have increased the sizes larger than 2 in. by as much as 20 per cent. at some mines. Tiffany and McKitterickl report the results of an investigation they made at a mine in southern Illinois in which, by a carefully controlled

Jan 1, 1931

A major high grade zinc deposit, Dugald River has fine-grained and complex mineral associations which provide considerable metallurgical challenges for both mineral dressers and downstream processors. A long history of metallurgical testing focusing on mineralogy and flotation concentrate production has shown that while separate lead and zinc concentrates can be produced at saleable grades, high levels of iron, and particularly manganese, are likely to place constraints on the marketing of zinc concentrate produced from deeper zones where coincidentally lode development is at its maximum. Testwork has focused on characterising the flotation response of ore types ranging from banded and stringer sulphides to brecciated ores in a variety of sulphide matrices. A high level of variability with lower than expected metal recoveries has been indicated across some of the higher grade brecciated ores. However, the dominant slatey breccia has generally provided the best results. Heavy media preconcentration testwork has been moderately encouraging and at this stage, although value adding downstream of concentrate production on-site is not seen as an economic option processing developments are being monitored on a broad front. Providing satisfactory means can be developed for handling manganese during downstream processing of the concentrate, it is not difficult to see a world-class operation emerging from the resource in the medium-term Future.

Jan 1, 1993

By R. P. Rothwell

THE first difficulty mentioned is that in some instances two or more beds of coal separated by sandstone or slate rocks of considerable thickness in one part of a basin, are found running together in another part. Of course, we may happen to strike first the part of the basin where there is but a single seam, and in this case the bed would appear 60 divide into two or more branches within a short, distance. Such cases are not rare in the anthracite coal-fields. I would suggest as an explanation of this phenomenon the gradual sinking of the peat-marsh-the embryo coal-bed-on one side, and the moving forward of the marsh, so that on one part of the bed the formation of peat would still be progressing, while another part, being under water, would be covered with mud and sand. Thus we have different portions of the same bed of different ages. Now if the sinking of the marsh be stopped for a time, the bed will become thicker in the portions left exposed, and if the sinking now changes in direction, so that the part that had previously gone down commences to rise, we should have the phenomenon of a bed, continuous throughout, with one portion overlying another, and separated from it by rock strata. These are exactly the conditions observed in splitting beds. While one side of the lake is sinking, and the peat marsh moving on in that direction, the other side may be rising,

By Jennifer B. Leinart

Sixty percent of the mines responding to the sixth annual Mining Cost Service labor survey reported increases in wages averaging 3.4% over the preceding 12 months. Only one mine reported a decrease in wages and this was accompanied by initiation of a substantial profit-sharing plan. Thirty-nine percent reported no change in wages. Thirty-seven percent reported using some form of incentive bonus plan. Mining Cost Service annually surveys coal, metal, and industrial mineral mines throughout the United States. Information about wages, benefits, and incentive bonus plans is part of an extensive data collection program to monitor cost areas of significance to the mining industry. This year, 131 mines responded to the survey. The data is collected by sending questionnaires to personnel managers at active mining operations. The information included in this article was taken from the returned forms, from labor contracts provided by some of the mines, and from followup telephone calls. This year's data was collected between November 1988 and February 1989.

Jan 1, 1990

By Igor Kuzymin, Isaak Maximov, Iuriy Akkerman, Galina Aksenova, Valentina Sentemova, Nataliya Trubechkova

"The Russian Federation possesses large reserves of oxidized ferruginous quartzites. These ores are currently mined together with magnetite ores and are stockpiled on account of unavailability of an efficient processing technology. This paper presents the results of investigations performed on the ores from the largest oxidized ferruginous quartzite deposit located in the Kursk Region iron-ore basin of Russia. The objective is to produce concentrate with iron content at least 66% and silica content within 5%. A processing technology was, developed under laboratory conditions, which included ore preparation, wet magnetic separation in weak and strong fields and reverse cationic flotation with addition of caustic soda, dextrin and Lilaflot 811M (alkoxy propylamine) collector from Akzo Nobel. The developed technology produced iron recovery concentrate with iron content of nearly 67%, and that of silica - 4.1%, iron recovery into concentrate being 72.6%."

Jan 1, 2014

By H. Ogasawara

Information on rock stress is important for safe mining in seismically active ground. On a major gold mine, a few tens of crews are continuously conducting geological drilling with small pneumatic machines. However, stress measurements are not often carried out in South African deep-level gold mines. One of the reasons is the drilling diameter that overcoring requires, which is much larger than the diameters used in regular geological drilling, e.g. Boart Longyear Metre Eater, which drills A[O] or B[O] holes. Larger diameter holes result in slower drilling advance, more load in transportation and handling at sites, and higher cost. In order to enable overcoring in BX size (60 mm diameter), we modified the compact conical-ended borehole overcoring (CCBO) technique that has been suggested by International Society for Rock Mechanics (ISRM) and was originally designed for NX drilling (76 mm diameter). With a single overcoring, the 3-D stress tensor can be determined. We tested this modified method at a depth of about 3 km at Moab Khotsong mine in South Africa. We worked with drilling crew who usually work at geological drilling with the Metre Eater. In January 2011, we tried using regular geological drilling tools (a sequence of a normal BX bit, reamer, and rod) without success. In August and September 2011, introducing stabilizers and thin BX bits, we succeeded. We could complete a cycle of procedures necessary for an overcoring, including shaping the borehole-end conically, glueing a 16-element strain cell, and overcoring, within 2.5 hours. Only 10 cm overcoring is needed, which increases the chance of successful overcoring in heavily fractured conditions. This modified method is suitable for up-dip holes to depths of 10-15 m from tunnels, and has the potential to be widely used at the initial stage of geological exploration drilling at many localities.

Jan 1, 2012

By M. A. Tomlinson, A. Di Feo, T. C. Cheng

"Goldcorp is evaluating the potential for economic reprocessing of historic tailings at several sites, including the Aunor A facility located in Timmins. The overall project is investigating the ability to recover value, remove sulphide minerals and alternative tailings re-deposition strategies. Desulphurization of tailings will eliminate potential acid generation while improved tailings re-deposition could reduce long-term liabilities and closure costs. Through a task-share project between CanmetMINING and Goldcorp, tailings obtained from Aunor A site have been characterized using mineral association analysis and diagnostic separation techniques. The selected tailing samples contain about 2 g/t of gold. Mineralogical analysis has identified coarse agglomerates bound with gypsum and significant free gold, confirmed by high recoveries in cyanide leach tests. However, despite no evidence of surface passivation on the minerals, conventional flotation techniques were found to be ineffective in concentrating gold or sulphides due to the high fines content and highly agglomerated particles.INTRODUCTION Aunor Mine is one of the historic mines that belongs to Porcupine Gold Mines (PGM) in Timmins, Ontario. PGM has undertaken an extensive mine closure program to remediate the legacy and closed mines with the funding supported by operating mines since 2006. Over the course of 100 years of operation in the Porcupine camp, it is estimated (Stevens et al., 2013) that about 130 million tonnes of tailings have been generated. Aunor Mine produced 2.5 million troy ounces of gold between 1940 and 1984, while processing over 7.6 million tons of ore. The original gold grade of Aunor Mine ores was about 10 g/t. With 95% gold recovery at the time, an estimate of 0.5 g/t of gold remains in the Aunor Mine tailings. Aunor Mine has two tailings impoundment areas: designated as Aunor A and Aunor B. The two sites are similar in size, about 7 hectares each. The amount of tailings in the Aunor A site alone is about 3.2 million tonnes. In 2017, bulk tailings were sampled from five designated locations in Aunor A. They were characterized using mineral association analysis and diagnostic separation techniques. The bulk tailings samples contained about 10% total sulphur, 10% iron, 2% arsenic and 2 g/t of gold. The prime objective of this collaborative work between CanmetMINING and Goldcorp is to facilitate the timely development and deployment of innovative tailings reprocessing solutions, specifically in the areas of desulphurization, and recovery of metals. This work targeted specific tailings of interest to Goldcorp which goals are to improve its environmental footprint and to reduce long-term liability. Thus, it is imperative to look for innovative reprocessing options that can overcome not only technological challenges but also achieve economic benefits to offset the costs associated with reprocessing the tailings. Moreover, the greater goal is to demonstrate and deploy tailings reprocessing solutions to solve one of the industry’s most difficult challenges for a sustainable mining industry in Canada."

Jan 1, 2019

Notwithstanding full concurrence with the dictum of a famous scientist that "definitions are the most accursed of all things on the face of the earth," in view of the considerable confusion which exists in jigging nomenclature, it is considered advisable to commence this paper with the following explanations of the terms which will be used throughout the text.Jig Bed. The whole layer of material lying on top of the jig screen.Ragging. The layer of denser material lying immediately above the jig screen, which is too coarse to pass through this screen and is confined horizontally by the cells of the top grid.Ore Column. The layer of ore pulp between the ragging and the top-water.Top Water. The water, carrying fine material in suspension, which flOiWS over the surface of the jig bed.Hutch Water. The water added to the jig below the screen. (Except for the water discharged with the hutch concentrate, the "hutch-water" eventually becomes "top-water.")Feed Water. The water in the ore pulp fed to the jig.(This water becomes part of the "top-water.")Pulsion. The period of the jigging cycle during which the water is moving upwards relative to the particles in the jig bed.

Jan 1, 1937

By M. Sandin

According to the world bank1, the mining industry consumes up to 11 percent of global energy use. In comparison, 70 percent of mining projects from the six largest mining companies operate in water-stressed regions. To steer the direction of the process industries toward more sustainable practices, more than 40 governments have adopted a price on carbon. This measure includes additional taxes on the use of fossil fuels, trade programs, new standards for renewable energy, energy efficiency mandates, more stringent emissions regulation, carbon offsets, etc. This emphasis is also supported by investors shifting their priorities to reduce risk by focusing on long-term plans, including environmentally friendly operations. The metals and mining industry is at the core of the green energy mix and electrification of vehicles. This new trend creates an astronomical increase in demand for minerals. Under a 2-degree scenario, according to the latest analysis from the world bank, as new energy technologies continue to grow, it is expected that all minerals to double in demand, and the distribution of these materials will depend on their application. • Solar panels, will account for 87% of the aluminum demand, and more than 95% of silver • Wind turbines and geothermal plants will require 98% zinc and 64% titanium. • Solar and wind energy alone will demand more than 74% of the global supply of copper, and this is without considering wiring or other infrastructure to connect the grid • Battery storage accounts for 100% of the graphite and lithium demand. (Hund, 2020) • Other materials, such as nickel and steel, are also projected to more than double in demand as they are cross-technology minerals. These materials require a manufacturing process that is accountable for the emissions proper of the transformation process. It requires that these processes move from a hindsight mode focused on reporting to a forecasting mode based on run-time measurement of GHG emissions. This is a critical first step in companies realizing an economic return for doing the right thing for the environment and their communities.

Feb 1, 2023

The usual metallurgical, engineering and administrative activities associated with the handling and smelting of ores, and the subsequent handling and treatment of the products of smelting, present also problems of hygiene that engage the earnest attention of executives in all well-managed concerns.Again, associated with the employment of any considerable number of men, there is always present the problem of accident prevention.INDUSTRIAL HYGIENE.In the earliest records of lead min.ing and smelting there are references to the injurious effects of lead oh the health of the employees, and, with the advancement of medical science, lead poisoning has been the subject of many works by various authorities in many countries.Moreover, in practically every civilised country, there are laws governing the conduct of the lead industry, and in most cases these laws stipulate that employees shall receive compensation for disability caused by lead poisoning.This provision gives the problem an economic aspect. Apart from the legal and the economic aspects, however, there is the humanitarian aspect, which implies that the...

Jan 1, 1937

By Ramana. G. Reddy, Haoxing Yang

The electrodeposition of zinc from zinc oxide using urea and choline chloride mixture in a molar ratio 2:1 is investigated in different experimental variables, namely, the concentration of added [BMIM]HSO4, temperature, and applied cell voltage. The additive, [BMIM]HSO4, was determined to have beneficial effect on the current efficiency, energy consumed in the process and surface morphology of the deposits. The highest current efficiency (92.6%) and lowest energy consumption (2.92kWh/kg) was obtained for solution with 20mg/mL [BMIM]HSO4. The morphology showed the formation of absorbed additive layer on the cathode at higher concentration of additives. Experiments were conducted at different temperatures between 343K and 388K and at various applied cell voltages between 2.7V to 3.6V to determine the best experimental conditions. By varying temperature, highest current efficiency (91.3%) and lowest energy consumption (2.69 kWh/kg) was obtained at 373K. The electrodeposition process is enhanced between the applied voltage 3.0-3.3V by achieving lower energy consumption (2.75~3.06kWh/kg) and higher current efficiency (88.4~89.7%). SEM images showed grain size is significantly increased in higher applied voltages. While at higher temperatures, it seemed to generate particle growth as clusters at the outer deposit layer.

Jan 1, 2014

By E J. Hancock, K H. B Chu

Failures within hard rock underground excavations have historically been defined by a depth of failure, estimated in the field or through individual measurements, with a simplified failure geometry; such as 1/3 span, cubic or paraboloid. This simplified shape, volume and mass of failure is typically used to estimate in situ demand as a simplified discrete point. However, the highly variable failure geometry indicates simplified methods to estimate the mass can be erroneous in comparison to high precision LiDAR scans. Advances in technology have enabled the accurate capture of failure geometry and allow a far more accurate analysis of failures to be completed. This case study investigates a number of real-life failures to accurately define the failure geometry, the distribution of the failure parameters and compares this to traditional methodologies. This paper also outlines a suggested means of standardising failure geometry parameters whilst accounting for their variability.

Nov 29, 2022

By H. Hitchen

THE object of this paper is to present the various facts that l1ave been revealed during lengthy investigations into the performance of all types of ropes on different hoisting installations. It then goes on to suggest means by which most of these findings could be usefully employed to obtain more economical rope lives with increased safety. SHAFT HOISTING ROPES Four basic designs of ropes are now employed for hoisting duties: (1) Six-strand, round strand ropes with fibre cores. (2) Six-strand, triangular strand ropes with fibre cores. (3) Non-rotating, multi-strand ropes. 0) Locked coil ropes. Round Strand Ropes (Figure 1) Very solid and reliable ropes can be obtained with this simple geo-metric design of strand. 1'1?iangula1? Strand Ropes (Figure 2) Owing to the fact that the wires in the strands are bent over a triangle, they do not seat quite so solidly as when they are bent over a circular core wire, as is the case with

Jan 1, 1963

The relationship between comminution testwork results and the milling circuit that is subsequently selected is not a direct one and frequently involves recourse to databases of past test results. This in itself reflects the lack of a systematic engineering approach in the design process. This paper reviews comminution tests for SAG mill design in an attempt to identify where the essential information comes from that will be used in mill selection. The conclusion is that results from traditional test methods, including obscure and little used procedures like the Mokken test, are more valuable from an engineering perspective than parameters for breakage rate based modelling. Suggestions are made on ways in which existing test procedures can be enhanced in order to generate parameters that can be directly related to characteristics of the milling circuit being designed.

Jan 1, 2002