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By A. Rios

ENAMl's Paipote Smelter commenced operations in 1951. At present, it processes 230,000 tonnes/year of green feed in a conventional smelter, which comprises one reverberatory furnace, two Hoboken, one Peirce-Smith converters and one rotary anode furnace. The feed is composed of 83% copper concentrate and 17% metallic copper precipitates, which results in a feed average grade of 32% of copper content. The final products are 75,000 tonnes/year of copper anodes and 48,000 tonnes/year of sulphuric acid. At present, the plant is undergoing a modernization to expand the smelter capacity to 300,000 tonnes/year of green feed and increase the sulphuric acid production to 100,000 tonnes/year. This will be achieved with the installation of an El Teniente Converter and an expansion in the acid plant. The work began in November 1991 and is scheduled to be in operaton by March 1993. The paper provides an overview of the modernization plans and results achieved to-date.

Jan 1, 1993

By D. Bienstock

In connection with air-pollution studies, the Bureau of Mines is cooperating with the U.S. Public Health Service in investigating the use of solids for removing sulfur dioxide in concentrations of less than 0.5 percent from combustion and waste gases. Removal of sulfur dioxide at flue-gas tempera¬tures would no longer result in the cooling of scrubbed gas, which is inherent to liquid scrubbing processes used exclusively in industry today. Results are reported of extensive investigation, using metallic oxides as absorbents, adsorbents, and oxidation catalysts at 130° and 330° C. (temperatures at which flue gas may be treated in powerplant practice). The most active absorbents tested were the oxides of manganese, cobalt, copper, and alkalized alumina; 23 to 33 grams of sulfur dioxidn were removed by 100 grams of absorbent at 130° C., while scrubbing more than 90 percent of the sulfur dioxide from a simulated flue gas, and 19 to 61 grams of sulfur dioxide were removed at 330° C. A more detailed study is reported on absorption and regeneration, using manganese oxides and alkalized alumina. Adsorption of sulfur dioxide on activated carbons and molecular sieves at elevated temperatures is considerably less efficient than removal by absorption--a maximum of 7 to 8 grams of sulfur dioxide could be removed with 100 grams of adsorbent at 130° C. A potash-promoted vanadium pentoxide is effective in converting sulfur dioxide to trioxide; complete conversion in a simulated flue gas containing 0.35 percent sulfur dioxide was obtained at 365° C. Pilot-plant and cost studies are being made by the Bureau to determine the economic feasibility of removing on an industrial scale the sulfur dioxide present in gases in low concentrations.

Jan 1, 1961

By T. S. Golosinski

This paper identifies the components of belt conveyor shifting force as a vertical force. Pv, horizontal force, Ph, and longitudinal force, P1. A method for estimation of these forces is proposed, which relates their value to the properties of the conveyor structure and rails, shifting operation parameters, and other site-specific conditions. The effect of this force on shifter behaviour is analysed and guidelines are developed for selection of a suitable shifter. Also discussed are the requirements of the shifting operation for other equipment.

Jan 1, 1986

By Christos Roumpos, Philip‑Mark Spanidis, Francis Pavloudakis

Coal mining operations are large-scale, long-term frameworks of high complexity. Mining organizations accumulate, develop, and leverage knowledge from diverse scientific and technological fields as a result of these operations. Both practical experience and existing literature indicate that knowledge management (KM) methods within the mining industry primarily target solving immediate technical challenges and operational requirements. However, they are not commonly regarded as strategic tools to enhance the performance and competitiveness of mining companies. Empirical evidence from the Greek mining industry suggests that the management of available knowledge is intricate, less effective, and dysfunctional. This paper presents a methodology based on the principles of quantitative research (QNR), collaboratively conducted with a group of mining experts, to assess the KM landscape in the Greek mining industry. The methodology involves a structured data collection framework using questionnaires, subsequent statistical analysis, a discussion on critical methodological aspects, and an interpretation of results focusing on key aspects useful for planners and designers of KM systems in the mining industry. Finally, the paper concludes by summarizing the methodology’s outcomes and proposing further perspectives for research.

Mar 16, 2024

By Graham Walker

A new Code of Practice for the brake performance of off -highway vehicles was established in Alberta in 1976. Vehicles loaded to gross vehicle weight must be capable of stopping with mechanical brakes five times in quick succession on a grade of 10 per cent from a speed of 28 miles per hour. Comparative trials of various brake systems have been carried out and some combinations capable of meeting the Code are identified. Some problem areas in truck braking are reviewed and potential developments indicated.

Jan 1, 1977

By L. H. Cole

Introduction The increasing importance of the gypsum industry in Canada is evidenced by the fact that the production has increased from 473,129 tons valued at $809,632 in 1909 to 1,205,846 tons valued at $3,622,007 in 1928, an increase of over 155 percent in quantity, and of 347 percent in value, in the 20-year period. Although the export trade in crude gypsum still forms a large proportion of the industry, it is gratifying to see that the home consumption is steadily increasing, and while the percentage of the crude gypsum mined that is manufactured into the calcined products in the country is only 16.8 per cent, its value is practically 50 per cent of the total gypsum production of the whole country. It is to be hoped that each succeeding year will see an increase in the amount manufactured in Canada, and, with the steady growth of the country and a serious endeavour to capture a part at least of the world market in gypsum products, the outlook for the industry is decidedly promising. The value of gypsum as a commercial commodity has been known from the time of the early Egyptians; in fact its value for certain purposes has been known so long chat the date of the discovery of its peculiar properties is unrecorded.

Jan 1, 1930

By T. W. Turk, S. A. Sass

The engineering design features of the Mercur Gold Project crushing, grinding, carbon-in-leach, bullion, reagent, and tailings disposal areas will be discussed in this paper. It presents a project overview and flowsheet along with selected design alternatives. During the engineering phase, major equipment and other features were selected to optimize design within site location and environmental constraints. The project team organization and procedures were adopted to accommodate multiple optimization studies while maintaining a tight engineering schedule.

Jan 1, 1985

By A. CHESTER BEATTY

MAGNESIUM oxide is by far the most refractory of the common oxides, since it has a melting point of 5072 deg. F. as compared with 3110 deg. F., the melting point of silica (crystobalite) ; 3722 deg. F., the melting point of alumina (corundum) ; and 4127 deg. F., the melting point of chromite (Cr2O33FeO). Its large-scale use in the lining of metallurgical furnaces dates back to the latter part of the nineteenth century, when extensive deposits of magnesium carbonate were discovered in southern Austria in the province of Styria. Before the development of Austrian magnesite, calcined dolomite, a mixture of lime and magnesia, was used in basic steel-making furnaces. The lime in the dolomite was quite objectionable, since it slaked on exposure to the atmosphere, and dolomite therefore could not be made' .into permanent furnace bottoms or into brick. The Austrian magnesite, with its very low lime content, was free from these objections and soon displaced much of the dolomite. With the extensive development of basic steel-melting, the rise of the copper industry, and other metallurgical and chemical processes which dealt with chemically basic substances, the use of magnesite grain and magnesite brick increased rapidly.

Jan 1, 1931

By Patrick Sullivan

Over the past few years, successful operations for processing phosphates employing the Grate-Kiln System have been achieved. Control and instrumentation philosophy followed in these installations are described and analyzed. Concepts utilizing digital techniques and computer systems appropriate for similar installations are also discussed.

Jan 1, 1967

By O. J. Hollister

Jan 1, 1888

By George E. Cole

Introduction In view of the fact that, during the past year, two Manitoba mines-Flin Fion and Sherritt Gordon-have entered the list of producers and have materially increased that Province's contribution to the metal production of the Dominion, it would seem appropriate at this time to review the progress of the industry in the Province, with particular reference to the out-standing metal-mining developments of the past decade. That these two mines have been able to continue their operations in spite of the low prices of copper and zinc adds a touch of brightness to the industrial life of the Province. Depression in metal prices is not encouraging to the mining industry, but it does stimulate efficiency in methods and costs of production. As two thriving towns have grown around the two mines, the will of the management to carry-on is of great consequence to Manitoba, this year so hard hit by the .agricultural depression. And, much as it is a pleasant feature in the mining situation that these mines have been able to continue operations, nevertheless it must be noted, in reviewing the mining developments of the past few years in Manitoba, that the Province was fortunate enough to profit by good times, in that an industry was established which gives evidence of permanency. In the metallic field, the section of Manitoba that first received attention from prospectors was the boundary district, west of the Lake of the Woods. Several claims were staked here at the time of the gold boom in the neighbouring Ontario area. But the first real interest in metalliferous deposits dates from the discovery of gold in March, 1911, in quartz veins on the shores of Rice lake, some twenty miles east of lake Winnipeg. Systematic and organized prospecting of the pre-Cambrian areas of the Province may be said to have commenced with that discovery. The first gold discovery in northern Manitoba was made at Wekusko (Herb) lake in 1914. This was followed by the discovery of the Flin Flan and Mandy copper ore-bodies in 1915 on Flin Fion and Schist lakes, respectively.

Jan 1, 1932

By B. P. Watson, A. Carpede, W. O. Kekana, N. Fernandes, W. Theron, M. P. Mahlangu, G. Betz

The research described in this paper was done to confirm the Upper Group 2 (UG2) PlatMine peak pillar strength formula (Watson et al., 2007), which was determined from a back-analysis of failed and unfailed pillars. Underground measurements were made on a stable pillar that was loaded by firstly reducing it’s length and then by mining the surrounding pillars until pillar failure took place. The pillar was instrumented with suitably positioned strain cells and closure meters, which allowed both the average pillar stress and strain to be determined. The paper describes the methodology applied to identify a suitable position for the instrumentation, as well as the results. A stress/strain curve is presented for a UG2 pillar with a w/h ratio of 2.0, at Booysendal Platinum Mine. The measured pillar strength was similar to the predicted strength using the PlatMine pillar strength formula for UG2 pillars. The PlatMine formula has been successfully implemented on Booysendal Platinum Mine, and about 3 670 pillars have been cut without a single failure. An additional revenue of US$1.3 billion was calculated for the 25-year life of the mine as a direct result of the improved pillar design, given the January 2020 platinum group metals basket price. An extended life of mine and better mining efficiencies will also be realized.

Aug 1, 2021

By A. J. Hofmann, G. P. R. van der Merwe, J. E. W. Holm

"A new approach is proposed to perform relativistic comparisons between alternative operational risk management solutions by taking into account the impact of each operational activity on overall system performance. A specific case study, to which this new approach is applied, involves the deployment of safety systems in underground mining operations. Conflicting objectives to be satisfied are the minimization of risk to human lives and the minimization of production losses. As the focus in this case is primarily on the mitigation of risk, the approach that was applied is referred to as activity-based risk (ABR) analysis. Existing development process and risk management methods used in the South African mining environment were analysed by means of observations, a case study, technical documentation, and literature review. It was evident from this analysis that a discontinuity existed between the acquisition and operational phases in terms of the management of safety risk in the acquisition of electronic safety equipment when viewed from a full lifecycle perspective. This discontinuity could be addressed by defining a risk perspective in the system development phase by employing ABR in the preliminary design phase of a system’s engineering life-cycle. The focus of the ABR system development process is to find the functional definition and configuration of safety equipment that addresses both safety and productivity when taking into account human performance variability. In doing so, a balance between productivity and safety is found in a relativistic sense. IntroductionIn any system life-cycle, two major phases exist, namely system acquisition and operation (including maintenance). A distinction is made between acquisition and procurement, where acquisition includes system development and integration as specific engineering activities. In the development phase of a new system, conceptual design, preliminary design, and detail design phases follow in this order to define a complete system, after which the system is put into production and implemented in an operational environment—these activities chronologically define system acquisition in the context of this paper. It is not uncommon that differences exist between the risk management perspective during acquisition of a system and risk management perspective during operation, where nontechnical aspects are often ignored during acquisition, but are then encountered and found to be problematic during operation (Leveson, 2012). These differences also exist in the mining industry."

Jan 1, 2017

By Ernest A. Curth

A 3-month study in 1971 of the Essen Roof Support and Rock Mechanics Research Center's program of roof and support evaluation included 25 mine trips. German miners must adopt mining methods and environmental control measures involving methane drainage and water infusion to improve productivity under severe natural conditions. Pressing problems in ground control must be solved such as cavities in front and above the supports at longwall faces and excessive convergence in gate roads. The Center developed automatic data processing methods to quantify the results of roof and support surveys and to establish criteria. Another approach to ground control is the study of mine models. The Center's laboratory has the facilities to test elements of powered roof support and whole assembled units. Face automation and roof control by powered shields are novel developments that are under close scrutiny in the field as well as in the laboratory. Though the Essen Center's roof and support evaluation techniques are tailored to the needs of the coal mining industry of the Federal Republic of Germany under conditions vastly different from those in the United States, some application may be found here, for instance, monitoring faces and roadways and preventive maintenance of hydraulic systems.

Jan 1, 1974

By Ian S. Ross

The emphasis in this paper is focussed on dry bulk car go or the same cargo converted to slurry form for ease of handling. It is this type of cargo which is of primary interest to the mining industry whose products it represents to a large extent. The design problems associated with the handling of liquid bulk and of unitized cargo are sufficiently different to be treated separately. This paper then will consider the port handling facilities of dry bulk commodities as part of a system consisting of (1) the movement of products to the port area, (2) the movement of products out of the port area and (3) the handling of products within the port area itself. Expanding within these three components of the total transportation system, the paper will discuss the various difficulties encountered concerning the mode of transport into the port area and the method of handling product from transport to stockpile. Secondly, and before discussing the port area itself and in order to complete the conditions under which the port must operate, the movement of products out of the port area will be covered dealing with such items as the accommodation of the ship, problem associated with the very large ships, optimum berthing arrangements and the need to consider the various costs associated with the vessel. Finally the paper will review within the port or interface area such items as stockpiles, method of recovery, inventory control and an outline of the common design difficulties encountered. In all cases the relative influence on the total transportation costs of each of these dry bulk transportation system components will be considered.

Jan 1, 1972

By J. C. Meeks, C. L. Klingman

An instrument that is sensitive , portable , safe , and low in cost was developed by the Bureau of Mines for detecting helium leaks by comparing the thermal conductivity and flow rate of the atmosphere around the suspected leak against a reference of helium- free air . A vacuum pump pulls the sample gas through a restriction and over thermistor elements , the combined electrical output of which is affected by thermal conductivity and flow rate of the sample gas . Tests showed that the battery - operated Helium Leak Detector was effective and rugged instrument that could be operated safely in explosive atmospheres . The instrument could also detect , but not identify , other gases such as methane , hydrogen , argon , carbon dioxide , and Freon 12 .

Jan 1, 1964

By C. Vipulanandan, M. Dawood, Dongmei Pan

"With the aging infrastructure, there is a need to maintain and extend the service life of steel structures in general and steel piles in particular. Steel piles support not only vertical loads but also dynamic horizontal loads in onshore and offshore applications. In order to select the appropriate methods to repair corroded steel piles used in onshore and offshore application, corrosion mechanisms were investigated with the rate of corrosion in various environments. The corrosion rate of steel in soil, water and soil-water interface varied from 2 to 500 µm/year. Based on literature review and analyses, the repair methods can be broadly characterized as protective coating, electro-chemical methods, wrapping and encasement and partial replacement of steel. Also, methods to evaluate the repair materials and the repair configuration have been documented.IntroductionOne of the biggest challenges facing the aging infrastructure is the materials loss and deterioration due to corrosion. Many studies indicate that in the US alone, costs due to corrosion loss is more than $276 billion annually (Michiel et al., 2010). Corrosion is the major cause of deterioration of steel structures and components (MNC, 2005). Load bearing steel piles are used as foundations for various types of structures and hence corrosion is very much influenced by the environment such as soil, water and soil-water interface. Corrosion of steel pile foundations may result in reduced capacity in the axial and lateral directions. Hence, understanding the rate of pile corrosion is essential to select the appropriate repair methods to avoid excessive deflection and failure (Decker et al. 2008).To prevent the deterioration mechanisms that attack a pile, it is fundamental both to identify and understand the deterioration mechanism that has been the cause of damage. Understanding the deterioration mechanism allows the engineer to design a repair that will combat this type of damage. It is widely recognized that the corrosion of carbon steel in soil, water and soil-water interface proceeds according to the following simplified anodic reaction and cathodic reactions in the presence of oxygen (Decker et al. 2008)."

Jan 1, 2017

By Vincent Castranova, Jane Y. C. Ma, Joseph K. H. Ma, Chang-geng Mo, Carl J. Malanga

"A group of bisbenzylisoouinoline alkaloids has been shown to exhibit various degrees of effectiveness in preventing silica-induced fibrosis in animal models [1, 2]. The objective the present study was to characterize the binding of several of these alkaloids to phosphatidylcholine vesicles and rat alveolar macrophages using fluorometric and equilibrium dialysis methods, respectively. The lipid binding affinity of these alkaloids was found to depend upon several structural factors including hydrophobic substitutions, chiral configurations, and double oxygen bridge-restricted conformation of the benzylisoquinoline moieties. Tetrandrine, which is a highly effective agent in preventing fibrosis, showed strong binding to both lipid vesicles and alveolar macrophages. In contrast, certain analogues of tetrandrine such as curine and tubocurine, which have little or no effect on silicosis, exhibited only weak binding to lipid vesicles and almost no binding to cells. The moderate binding affinity of fangchinoline to vesicles and cells corresponded to a moderate effectiveness of the compound as an antifibrogenic agent. Methoxyadiantifoline, an alkaloid of unknown antifibrogenic potential, also exhibited high binding affinities for lipid and cells. In conclusion, the results of these studies indicate that alveolar macrophages exhibit large binding capacities for certain members of this class of bisbenzylisoquinoline alkaloids. A positive correlation was observed between binding affinity to alveolar macrophages and the reported antifibrotic potency of these compounds. These data also suggest that the ability of these drugs to interact with alveolar macrophages may be a key step in inhibition of the progression of silica-induced pulmonary disease.INTRODUCTIONInhalation of crystalline silica is associated with the development of silicosis. This fibrotic disease is characterized by the appearance of concentric hyalinized nodular lesions in the lungs with the progressive development of pulmonary dysfunction [3, 4]. Many theories concerning the etiology of silicosis involve silica-induced activation of alveolar macrophages. Evidence indicates that in vitro silica exposures result in the generation of chemiluminescence, and the release of superoxide and hydrogen peroxide from alveolar macrophages [5]. Activation of alveolar macrophages has also been demonstrated after intratracheal instillation or inhalation of silica [5, 6]. Such excess release of reactive products from pulmonary phagocytes has been associated with damage to the lung parenchyma [7, 8]. In addition, silica exposure results in the release of mediators from alveolar macrophages, which enhance proliferation of fibroblasts and collagen synthesis by these pneumocytes [9-12]."

Mar 1, 1992

By Marc Carriere

Bright-orange couplings adorning piping systems are a common sight in just about every underground mine in North America. Grooved mechanical piping, the pipe-joining system that utilizes these couplings, is the preferred method for joining underground and plant piping systems in the mining industry, due to the ease and speed of installation and maintenance. However, the applications for such systems have traditionally excluded high-pressure systems. Most grooved mechanical couplings have a moderate working-pressure limitation, so high-pressure systems have required the use of alternative joining methods, typically heavy-duty flanges. However, the introduction of high-pressure couplings (up to 4,000 psi) has made the grooved joining method viable, and even preferable, for backfill, deep-mine chilled water and dewatering lines and other high-pressure piping applications. As engineers explore the use of high-pressure couplings, questions will undoubtedly arise about the joining method?s capabilities. This article will address the capabilities and specifications of high-pressure couplings, and compare flanged and grooved mechanical pipe joining in traditional as well as high-pressure underground mining applications.

Jan 1, 2011

By Derrick Chambers, George Kevin Chapin, M. Shawn Boltz

Seismic monitoring is one of the few noninvasive technologies with the potential to provide sub-surface geomechanical information to operators of large open-pit mines. Although passive seismic data has been used to refine emerging failure geometries and provide advance indication of surface deformations in the literature, doing so reliably in an operational context is much more difficult. This is due in part to difficulties in estimating and interpreting source locations and parameters in complex, low-stress open-pit environments. Additionally, the high costs associated with implementing, operating, and maintaining deep borehole seismic networks, which are most commonly used to monitor large open pits, can be difficult to justify, especially if monitoring benefits are not readily apparent. In this study, we explore the use of a near-surface nodal seismic deployment, which is commonly used in oil and gas exploration, for monitoring open-pit mining-related seismicity on a short-term basis. A deployment of 18 geophones was conducted on the surface in and around the Bingham Canyon Mine, a large open-pit mine near Salt Lake City, Utah, USA, where we find the small seismic array can detect and locate a variety of mining-related seismic sources, even with an extremely simplified velocity model. We outline the process of creating an idealized velocity model, developing a local magnitude scale, and interpreting the observed seismicity. Of note, we analyze a sequence of mining-induced events associated with a known structure on the south pit wall. We conclude with discussion on how surface-based deployments may be used to augment, or in some cases supplant, borehole seismic networks at large open-pit mines depending on monitoring requirements and objectives.

Apr 26, 2022