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By T. G. Phillips

"This paper gives an inside look at a bulk terminal and describes the preparations that must be made by a company in developing such a terminal and its position in today's traffic pattern. The following headings cover the subject material: (a) Traffic pressures, their detection and measurement, (b) position in the traffic flow -selection of site, (c) transportation connections -present and possible future routes, (d) engineering studies and costs, (e) contracts, the basic material for insured traffic, (f) financing, (g) budgetary control, (h) development of new techniques, (i) growth into new cargoes or cargo-handling methods and (j) consolidation."

Jan 1, 1968

By Donald J. MacNeil

The commercial carbonate industry of Cape Breton Island, Nova Scotia, began about eighty years ago with the opening of the Sydney steel plant. Significant carbonate deposits are confined to the Precambrian George River Grav" and the Mississippian Windsor Group. George River Group carbonates are thought to have formed as part of a stable platformal sequence. They are crystalline and lie within a dominantly quartzitic sequence. Of the four major sites for George River carbonates on the island, the most commercially promising are the dolomite at Kelly Cove and the limestone and dolomite at Glencoe. Kelly Cove dolomite has good potential for metallurgical, agricultural and fettling purposes; reserves approach 13.6 million tonnes. Windsor Group carbonates were deposited as marine sediments in basins formed by pre-Carboniferous fault blocks. Windsor dolomite reserves at Stoney Creek are only fractionally retrievable and hence are of little economic value. The Windsor Group's Irish Cove limestone has been quarried on a large scale since 1964; no undeveloped commercial deposits, however, remain in the group.

Jan 1, 1984

By J. T. Birkholzer, M. Rutenberg, K. -H. Lux, R. Wolters, J. Rutqvist, L. Blanco Martin

In this paper, we present numerical results corresponding to the Thermal Simulation for Drift Emplacement (TSDE) test, conducted in the Asse salt mine (Germany) between 1990 and 1999 to simulate reference repository conditions for spent nuclear fuel in rock salt. This test is of significant relevance for nuclear waste disposal in salt because extensive research and measurement programs were set up for the experiment. In our numerical study, we use two sequential simulators, TOUGH-FLAC and FLAC-TOUGH, and we investigate two-way coupled processes, focusing on thermo-mechanical analyses due to the main effect of heating. The two simulators used have recently been updated and are able to deal with large strains and creep processes. Moreover, specific constitutive relationships and coupling functions for rock salt and crushed salt under repository conditions are available. Within the framework of a benchmark exercise between Lawrence Berkeley National Laboratory and Clausthal University of Technology, the same scenario has been modeled in three dimensions using the two simulators mentioned. The main objective of the current, first stage of the benchmark is to evaluate the capabilities of these two simulators to predict relevant processes under repository conditions for high-level nuclear waste in saliniferous media. The comparison of the numerical predictions between them is very satisfactory, leading to a successful code-to-code verification. The comparison between measurements and numerical results shows that the most important processes are captured by the codes and constitutive models used. However, some differences exist between measurements and numerical results. These differences will be addressed in the next stage of the benchmark exercise, in which a parameter fitting effort will be undertaken. Overall, from the results obtained it can be concluded that TOUGH-FLAC and FLAC-TOUGH have the necessary capabilities to reproduce relevant processes under repository conditions for high-level nuclear waste in saliniferous formations.

Jan 1, 2015

By E. L. Horner

"Srnoky River Coal is capable ofprocessing 3 million tonnes per year ofrun-of-mine coal at the Smoky River Coal preparation facilities to produce 2.1 million tonnes of high quality, low volatile coking coal for export markets. Multi-seam surface and underground mining operations are scheduled to maintain raw coal feed to the plant. Two beneficiating circuits wash the coal. A heavy medium cyclone circuit cleans the plus 0.5 mm coal and a froth flotation circuit cleans the minus 0.5 mm coal. Clean coal is thermally dried, loaded into unit trains, treated for dust suppression, and transported to west coast port facilitiesf or export. Plant by-products are used as thermal fuel Jn an adjacent power station. Quality control procedures ensure efficient resource recovery for a yield of uniform specification product, at a 7% ash level. Introduction Smoky River Coal operates surface and underground mines in the Smoky River coalfield. Approximately 3 million tonnes per year (mt/ a) of run-of-mine (ROM) coal can be processed at the coal preparation plant to provide 2.1 mt/ a of clean, high quality, low volatile bituminous coking coal. Coal is processed by heavy media and froth flotation cleaning circuits and is thermally dried.Raw Coal Characteristics The characteristics of the ROM coal, both in terms of quality and size consistency, vary with intrinsic seam qualities and mining methods employed. The two seams mined (No. 4 and No. 10) show distinctly different washability characteristics. Seam No. 4 contains relatively few middlings and can be readily cleaned by dense-medium cyclones and froth flotation to give a clean coal at specification ash content. Seam No. JO is more difficult to wash, and the ash content of the clean coal is higher than No. 4 seam at the same operating conditions. However, when the upper I m is excluded from the plant feed, the remaining lower section has washability characteristics similar to No. 4 seam. Coal mined by underground means sometimes contains caprock and consequently tends to be dirtier than similar coal mined by surface means."

Jan 1, 1985

By G. M. Ritcey, S. H. Lucas

"On the north shore of the St. Lawrence River, in Quebec, are located orebodies of low-grade titaniferous magnetite. The Quebec Mining Exploration Company (SOQUEM), who have an interest in the deposits, believed that beneficiation of the could generate sufficient revenue to defray the mining costs and the costs of transporting the ore to a steel production facility. A joint research project of SOQUEM and CANMET investigated alkaline roasting of a magnetic concentrate, followed by leaching of the calcine and separation and recovery of Cr and V by solvent extraction. Aluminum was recovered by precipitation.The present paper describes the roast-leach bench-scale and pilot-plant work leading to the development of the optimum conditions f or the integrated process.A plant flowsheet was developed for the treatment of 5 x 106 tons of magnetic concentrate per annum. Estimates of capital and operating costs were made.Based on a recovery of approximately 90% V, 85% Cr and 75% AI, the total hydrometallurgical plant fixed capital costs, including mining, concentration and shipping, are estimated at $1.021 x 109; the operating costs are estimated at $131.92/ton concentrate. Annual revenue from the Na2CrO4.H2O, V2O5 and A12O3 produced is calculated to be $421 x 106.IntroductionThe Quebec Mining Exploration Company (SOQUEM) acquired in 1968 an interest in four titaniferous magnetite orebodies located in Eastern Quebec. 85 miles north of Mingan on the north shore of the St. Lawrence River. The Mingan deposit, with an estimated tonnage of one billion tons, has a reported average grade of 43% Fe, 6.3% Ti , 1.60% Cr, 0.19% V and 6.1% Al with minor amounts of nickel. SOQUEM, on the basis of previous bench-scale data, believed that the recovery of chromium, vanadium and alumina by alkaline roasting would generate sufficient revenue to defray the mining costs and the costs of transporting the ore to a steel production facility on the coast. One of the approaches selected by SOQUEM for beneficiation of the ore consisted of a combination of magnetic concentration followed by alkaline roasting of the calcine."

Jan 1, 1980

By G. M. Ritcey, K. E. Haque

"Laboratory-scale sulphuric acid leach tests were conducted on Elliot Lake and Rabbit Lake ores in the presence of various oxidants, namely: Fe2(SO4)3, CI2, H2O2, NaClO3, MnO2, H2SO5, HNO3, Oxon e, K2Cr2O7, KMnO4, O3 and O2. Uranium extraction is significantly accelerated when an oxidant is present in the leach slurry. Uranium extraction of 96-99% can be achieved by maintaining the oxidation potential of the leach slurry in the range of400 to 500 m V (S.H.E.). A rough cost comparison of all the oxidant s indicates that the use of Fe2(SO4)3, 02, O3, C12, HNO3 or MnO2 is far less expensive than NaClO3 and the uranium extraction rates are similar to or better than with NaCIO3. For uranium extraction, it is concluded that gaseous oxygen (i.e., air or oxygen) would be the most effective and economical oxidant for the 24- to 36-hour leach of Elliot Lake ore; whereas for the 8- to I2-hour leach of Rabbit Lake ore, a strong chemical oxidant (e.g. NaCIO3, H202, 03, K2Cr2O7, H2SO5 or HNO3) would be a logical choice.IntroductionThe common practice for the treatment of uranium o res is leaching with sulphuric acid or with a carbonate-bicarbonate mixture. Generally, the latter process is ad opted when an excess (> 18%) of acid-consuming components (e.g., carbonate) is present in the ore. Irrespective of the nature of the leachant, the addition of an oxidant to the leach mixture is necessary to obtain a high uranium extraction.The maximum extraction of uranium can only take place when all the uranium is in the highest oxidation state (i.e.,U +6-uranic ion) . Because a certain percentage of uranium present in the ore is invariably in the lower oxidation state (i.e.,U+4-uranous ion) , the addition of an oxidant to the leach slurry is necessary to oxidize uranous ion to the uranic state."

Jan 1, 1982

By F. Parada Luna, F. Parada Torres, J. Salvo, A. Reghezza

In the pyrometallurgical processes of copper concentrates, arsenic is preferentially concentrated in the dusts carried by the gases as a result of their volatility and subsequent condensation in the gas cleaning train. In this work results obtained by alkaline leaching of the dusts from Ministro Hales roasting plant, belonging to Codelco, are presented. For the Ministro Hales plant the alkaline leaching would be an alternative to the recirculation of dusts to the roasting furnace. The experimental study considered NaOH and NaOH plus NaHS leaching of two samples of dusts, with 4.24 and 2.55% arsenic respectively. The results show that it is feasible to extract 90% of the arsenic and 50% of the antimony at room temperature using only NaOH, and when the temperature increases to 95ºC, the extractions of As and Sb increase. Copper remains in the solid residue with less than 1% dissolution, and the NaOH net consumption was approximately 140 kg/t of dust. In leaching tests with NaOH + NaHS, two types of methods were tested, baking plus leaching with water and direct leaching with a NaOH+NaHS solution. With the second method arsenic extraction increased to 95% and copper dissolution was less than 0.01% at 85ºC, NaOH 100 g/L, NaHS 90 g/L, 1.5 h and L/S ratio of 5/1 (L/kg). The bismuth remains stable in the solid in all cases. INTRODUCTION The presence of arsenic in copper concentrates has increased with time and the environmental regulations are becoming increasingly more stringent. In concentrate treatment pyrometallurgical plants, most of the arsenic is volatilized condensing in the gas train and is collected along with the entrained solids to form the flue dusts. Under these conditions, in smelters of copper concentrates with high arsenic content, the dusts are being treated in hydrometallurgical plants to extract and stabilize the arsenic, which also means that most of the copper contained in the dust is co-extracted with the arsenic. This affects the recovery of copper in the smelter and an alternative such as the selective alkaline leaching of arsenic, would allow the copper from flue dust to be recovered.

Jan 1, 2019

By Andrew Kerr

Abstract - The base-metal and PGE contents of samples from magmatic sulfide mineralization are commonly correlated with their sulfide contents, indicating that the metal contents of bulk sulfides remain approximately constant within a given prospect or part thereof. Calculated sulfide metal contents provide valuable information in mineral exploration and research, but there are few formal descriptions and analyses of the procedures. Sulfide metal contents are best calculated using an assumed value (35.7% S) for a typical pyrrhotite-chalcopyrite-pentlandite mixture, and there appears to be little advantage in accounting for sulfide species separately. Regression of metal data against sulfur is probably the most rigorous approach, but is not always practical. Above 10% S, calculations are very robust, but lower sulfide contents generally demand at least some correction for non-sulfidehosted metals. Such corrections can become significant below 5% S, and/or in olivine-rich samples. They are best accomplished by mass-balance calculations, using concentration data from unmineralized host rocks. Significant uncertainties are introduced by analytical errors for sulfur, base-metals, and PGE, which are commonly measured from separate sample aliquots. These combined errors in sulfide metal contents generally exceed ±10%, but expand further at low S contents. In general, treatment of data from samples containing <2.5% S must be approached with caution, especially for PGE, for which the exact host minerals may not be known. Application of the method in simple grade-potential assessment is straightforward, but research studies involving sulfide-poor samples are inherently more complex. Under-correction or over-correction of data for non-sulfide-hosted metals can lead to false negative or positive correlations between sulfide metal contents and sulfide content. As the latter may itself be linked to geological parameters, such as depth within an intrusive body, undue significance could be ascribed to such trends. There are also valid geological reasons for such correlations, and such data require careful assessment to separate true and artificial variations. Propagated analytical uncertainties increase significantly in sulfide-poor samples, and must also be borne in mind whenever data from different localities or units are compared and contrasted.

Jan 1, 2001

By Georges Houlachi, Akram Alfantazi, Michael Mahon, Maysam Mohammadi

Corrosion resistance of the lead-based anodes directly influences the purity of the final product in the zinc electrowinning process. The anodic MnO2 layer that is electrodeposited on the anodes during this process can protect the anodes against corrosion. Sand-blasted anodes generate a uniform, adherent and shiny MnO2 layer, which gradually blisters and eventually sloughs off after several weeks. In this study, we attempted to develop a new method to stabilize the MnO2 protective layer on the anodes during the electrowinning process by providing suitable nucleation sites for electrodeposition of this layer. MnO2 particles (P80=40µm) were used as seed material for this purpose. Different techniques of galvanostatic and cyclic voltammetry polarizations, scanning electron microscopy (SEM) and atomic absorption spectroscopy (AAS) were employed to investigate the performances of the MnO2-seeded lead anodes. The experimental results showed that growth of the MnO2 layer is influenced by the MnO2 seed particles on the anode surface. The MnO2 layers electrodeposited on the MnO2-seeded lead anodes were uniform and strongly adherent to the substrate. This layer was more stable than those formed on the PbAg anode without MnO2 seeding. This could provide the anode with a higher level of corrosion protection. Moreover, formation of undesirable MnO2 mud in the electrolyte and the rate of manganese consumption were decreased when the MnO2-seeded lead anodes were polarized. These observations could be attributed to the different properties of the electrodeposited MnO2 layer on this anode in comparison with that formed on the PbAg anode.

Jan 1, 2016

By W. L. Uglow

In recent years, the microscope has come to be recognized as a valuable aid to engineers whose business is the discovery, development, concentration or reduction of metallic ores. In many of the large treatment plants microscopical research has already an important status; and in the hands of efficient operators the microscope has indicated methods of solving ore problems resulting in the saving of thousands of dollars that otherwise might have been lost in tailings, or expended in freight rates or smelter charges. Failure to procure all the information that the microscope can supply concerning the physical and mineralogical characteristics of complex ores has in many cases led to the construction of unsuitable concentrators, just as the failure to investigate in detail the geological conditions of an ore deposit has often results in the squandering of money on shaft sinking, and mechanical installations which subsequent development of the deposit failed to justify. The great progress recently made in the selective separation of minerals by means of the various processes of flotation and leaching brings strongly to our attention, the scope of the field in which microscopical methods may be advantageously employed. The microscope enables one to observe the minute details of rock, ore, gangue, concentrate, tailing, matte, slag and metal, that are invisible to the naked eye. Furthermore, the technique of microscopal research has been so highly developed that a microscopist can not only observe, but deter-mine the compositions and measure the diameters of the mineral constituents in the ore to be treated. Magnifications of these constituents up to 3,000 diameters may be produced by the proper combination of eyepiece, objective, and projection apparatus, and the images thus viewed may be photographed through the microscope, and permanent records made of them.

Jan 1, 1924

By D. J. Charlton

"IntroductionMaintenance is a business, which to be successful, requires good management, systems and reporting. The prime objective of the maintenance management group, be they large or small, must be to anticipate and prevent interruptions in operations by keeping equipment in good mechanical condition. This objective should be carried out at minimum cost consistent with maximum productiveness.The objective of this chapter is to give an insight into the various aspects of maintenance management that must be considered to effectively and efficiently operate a mill complex. The degree to which the maintenance sub-systems are developed in an operating mill will be determined by the size of the mill and the needs of the operation.The criterion of the management system used is that the system serve the operation and not vice versa. The systems presented should be considered as tools and, as with all tools, they must be sharpened and replaced as the need arises or as more effective tools become available.To understand what is involved in maintenance management, it is worthwhile to consider a systems approach to analyzing management problems. This approach was developed by J.A.B. Rae while reviewing maintenance management systems for Cominco Ltd.A very simple system involving managing results and objectives is shown diagrammatically in Figure 1.The systems approach to organizational development involves four basic elements: an objective, a result, an activity and feedback. In the analysis, the activity element is broken down into individual actions that people could be held responsible for. If we introduce the action of operating into the diagram of Figure l, we arrive diagrammatically in Figure 2."

Jan 1, 1989

By Sean Hillacre, Arthur Lieu

NexGen’s approach to uranium processing design including the crushing/grinding and leaching of raw ore through to yellowcake precipitation and tailings management focuses on minimizing surface footprint, freshwater consumption, and human radiation exposure. Applying the concept of best available technologies economically achievable (“BATEA”), NexGen continues to research, evaluate, test and validate various advanced technologies that can be incorporated into the Project design, including distinctive tailings storage techniques. Additionally, NexGen is proposing that tailings generated from the mill processes be used as cemented paste backfill of stopes, as well as stored in a purpose-built, Underground Tailings Management Facility (“UGTMF”) comprised of several dedicated chambers. The paste backfill method of tailings storage is used globally, however, constructing purpose-built tailings chambers in waste rock is a new concept in uranium mining, which would typically be cost prohibitive for most projects given the expense to develop non-economic material for the sole purpose of storing tailings. The Rook I Project is uniquely positioned to implement the UGTMF due to robust Project economics and favourable technical setting which provides NexGen with the opportunity to set an elite standard for tailings management. When compared to conventional surface tailings management facilities, storing tailings underground as cemented paste reduces geotechnical, geochemical, environmental, and human health risks associated with tailings management. Additionally, the UGTMF vastly reduces the area of surface disturbance and allows for progressive decommissioning during the life of mine operations.

Jan 1, 2020

By N. B. Clarke

LIMESTONE, as a name, covers a great variety of stone consisting of varying amounts of calcium carbonate, magnesium carbonate, and impurities such as silica, alumina, and sulphate of lime. In the iron and steel industry, limestone is roughly divided into two classes, namely Calcite, when the magnesium carbonate content is below 10 per cent, and Dolomite, when the magnesium carbonate is over 10 per cent. In practically all metallurgical melting, the quality of the finished product is related to the character of the slag, and limestone is used as a flux to achieve the proper analysis and consistency. The function of the slag is to absorb the undesired elements of the bath and also to act as a protective cover over the metal. The carbonates of calcium and magnesium are the effective agents in fluxing, and the silica, alumina, sulphur, and other foreign matter are objectionable impurities which should be as low as possible, totalling not over S per cent and preferably below 3 per cent, since all of these so-called impurities must be fluxed by the lime and magnesia of the stone. When the lime and magnesia of the stone have to be used to flux its own impurities, there is that much less of these two oxides left for fluxing the impurities from the balance of the charge, and, as a result, more lime-stone must be used than is desirable with good practice.

Jan 1, 1939

By W. N. Roman

This paper will examine the challenges involved in ventilating and cooling South African mines, with particular emphasis on solutions to the issues of heat (generally associated with depth), mechanization and energy efficiency. Comparisons will be made with other international mining areas. Some of the deepest mines in the world are to be found in the South African goldfields. The Mponeng mine is approaching 4,000 m below surface, with virgin rock temperatures (VRT) of between 60°C and 70°C. Mining at these depths has only been possible with the use of large refrigeration plants supplying cold air, water and ice to the workings. In the Bushveld Igneous Complex, where most of South Africa?s platinum mines are located, similar VRTs are being experienced at significantly shallower depths. This is due to the different geothermal properties of the host rock between the two areas. Existing mines are being forced to go deeper and new underground mines are being planned and constructed in other areas with widely differing thermal conditions. South African metal mining has traditionally been labour intensive for historical reasons as well as for the narrow tabular nature of many ore bodies. Due to cost pressures and labour problems, some mines have been investigating the possibility of using mechanized equipment, both diesel and electric, to increase production and to improve efficiency. Studies have been carried out to determine the effect of the additional equipment on the overall ventilation system and some of the conclusions are discussed. The use of diesel equipment adds heat and pollutants to the ventilation air but, although electrical equipment has a lesser effect on the ventilation systems, it is generally less favoured due to claims of lower flexibility/manoeuvrability. Mechanization holds the promise of more concentrated mining activities but, with higher localized ventilation and cooling needs. Systems which will control the provision of air and cooling more effectively are required and are being implemented. In the 1990s and early 2000s, the South African economy experienced significant growth which was not matched by the growth in infrastructure. Consequently, at present there is a shortage of electricity generation capacity which affects large industrial consumers, including mines. Increasing levels of heat and mechanization will require more electrical energy for ventilation and cooling. There are many initiatives underway to save power or to shift consumption to periods of national low demand and these will be described.

Aug 1, 2013

By G. F. Miller

ONLY IN THE Province of Saskatchewan is natural sodium sulphate found in Canada in amounts large enough to make recovery economically sound. Geologists have estimated that the numerous deposits within the Province contain upwards of 200 million tons of Glauber&apos;s salt. There are twenty-one deposits in the Province which contain 500,-000 or more tons and about two dozen with lesser amounts. The first recorded production of sodium sulphate in Saskatchewan was in 1918. The company concerned, and others that attempted to develop the industry in its early stages, were unsuccessful. Their failures were caused by two main factors -lack of knowledge of efficient operating methods and the unstable market situation for the finished product. Today, the situation is changed in both respects and the product, commonly referred to as &apos;saltcake", is a very important chemical requirement of many industries throughout the world. Before proceeding with remarks on manufacturing methods it should be stated that, although this is a general paper on the manufacturing methods and end uses of the saltcake produced in the Province, the writer is, of course, more familiar with the plants operated by Saskatchewan Minerals than with other operations and perhaps may be excused for dealing more particularly with the plants of that Compa11y.

Jan 1, 1958

By Michel Ruel, Ali Soltanzadeh, Benjamin Légaré

High fidelity commercial process simulation packages can be used at different stages of a greenfield project, from initial plant design to operator training in the later stages. However, there are several factors that make the software less attractive for small and medium size brownfield projects, such as the licensing cost and the fact-finding manpower required for model design and simulator maintenance. In this paper a different approach is described. The knowledge gathered from operating personnel was used to implement higher level models based on plant data, operating heuristics, and experience rather than detailed component-level models. The computing platform used was a low-cost, well-established, control system vendor-independent software. Throughout this paper we demonstrate the success of implementing this model-based approach using two industrial examples. The first example is a simulation of the carbon monoxide (CO) distribution system at a metallurgical complex. The purpose of this simulator was to test new control strategies and PLC programs prior to implementation. CO being a toxic combustible gas, validation of the suggested control system changes was necessary for plant safety. Simulation of specific operating conditions helped alleviate concerns and improved plant-wide acceptability of the new operating philosophy. The second example is a boiler simulator at a petrochemical plant. The operator training simulator (OTS) was designed as a platform for experienced operators to practice handling rare or abnormal conditions. A customized medium-fidelity model was developed for this targeted application where the cost of a full scale high-fidelity model could not be justified.

Jan 1, 2016

By J. E. Dutrizac, R. J. C. MacDonald, J. B. O'Reilly

"Sometime around 3000 B.C., primitive metallurgists working in the mountainous regions of Asia Minor bordering on the Black Sea (Pontus) produced a soft, easily fused metal today known as lead. It appears certain that the first metal was made by reductive smelting of galena, but whether this recovery arose by the accidental inclusion of galena in the stones of a fire hearth or whether it occurred as a consequence of simple pyrometallurgical experiments on a series of interesting ""stones"" will likely never be known with certainty. The properties of galena, high metallic lustre, great density and facile cleavage, must have excited the ancients, and such ""stones"" would have been the object of primitive testing111 - Shortly after the discovery of lead, the ancients found that the controlled oxidation of this metal at elevated temperatures yielded smaller amounts of a more interesting material, silver. Again, it is uncertain if the production of silver by primitive cupellation techniques was the result of a fireside accident or the consequence of a deliberate experiment, but the important fact is that silver was produced shortly after the discovery of lead. The techniques for making lead and silver spread gradually throughout the entire civilized world, likely as a result of both technology diffusion and independent rediscovery. The physical properties of lead could not have been overly attractive to the ancients, but silver was a different matter altogether. The gleaming white lustre and relative immunity to oxidation quickly assigned silver to the precious materials category, a status it still enjoys. In early times, argentiferous galena was inevitably processed only for its silver values; lead was generally an unwanted byproduct and was frequently discarded as litharge (PbO) during the cupellation process. The silver was eagerly sought, however, and resulted in considerable mining activity culminating in the famous Athenian silver mines at Laurium at the southern end of the Athenian peninsula."

Jan 1, 1999

By I. M. Masters

Iron removal and control in processes employing pressure leaching technologies developed at Dynatec Corporation are reviewed. Discussions are focused on recent developments in the processing of nickel-copper matte and copper concentrates, and on the Ambatovy laterite project in Madagascar. Iron control and its implications on flowsheet design in the pressure acid leaching (PAL) treatment of laterite ores and in the oxidative pressure leaching of mixed nickel-cobalt sulphide intermediates are also discussed.

Jan 1, 2006

By J. M. Turnbull

THE primary objective of the young graduate, after the war, will be to obtain a suitable position within the Industry, with adequate pay and opportunity to advance. The positions available to meet this demand will depend on the magnitude and organization of the industry. The size of the mining industry, in particular, will depend on a number of factors, including depletion; new discoveries of mineral deposits; beneficiation of new kinds of mineral deposits, based on research; technical improvements, also based on research, enabling the mining of lower grade deposits; and complex social factors. The organization of the industry will depend on its control and management, which may be greatly affected by social conditions and changes, and may include a wider or a narrower use of technical services. The corresponding training or qualifications of graduates, to meet these conditions, calls for a consideration of educational requirements and facilities in relation to the conditions that are likely to occur. Some forecast of the probable future of the Industry, after the war, based on consideration of. the above factors, is necessary as a basis of discussion, since the graduate must find his place in the industry of that time, and find his work in maintaining and improving it, within the existent social framework. Social factors are pressing and? important at present and their future impact is uncertain. In considering these, a few quotations and extracts may be in order. "A new economic order, based on free access to the sources of raw materials, means free use of the world&apos;s wealth by all civilized nations" (The Pope. Also advocated by Churchill and Roosevelt in the Atlantic Charter). "Every citizen should have a voice in the conduct of business or industry which is ?carried on by means of his labour" (Archbishop of Canterbury).

Jan 1, 1943

By D. G. Brophey, J. A. O’Neill

"High costs, both in terms of human resources and financial costs, have long been the end result of accidents involving vehicles which continue to occur too often throughout our industry.For example, radio remote control LHDs too often seriously injure their operators in underground operations. Costly efforts are required by mine owners to provide safety bays and platforms from which their operators can work safely. In open pit operations, large heavy haulers have too frequently backed over vehicles or turned into vehicles unfortunate enough to be situated in their large blind spots. These are just two examples of situations that have occurred again and again under similar circumstances.Meanwhile, electronic methods of detecting proximity to vehicles have continued to develop. The time has come for the industry to think “outside the box” to evaluate whether many of these new methods can solve these recurring problems.This note takes a look at various types of proximity detection technologies that are in use today in other industries, and discusses the various potential applications within our industry."

Jan 1, 1998