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By P. C. Dagneau

QUEBEC CARTIER MINING COMPANY was incorporated in 1957 to explore and develop low grade iron are deposits in Northeastern Quebec. Four separate deposits were located and identified as being of ore quality and size to support commercial development. Said deposits were located at Lac Jeannine, Mount-Wright, Fire Lake and Mount-Reed. In 1970, in preparation for the replacement of the depleting Lac Jeannine are reserves, construction of an SS-mile railway extension was initiated, towards the newly selected mine site at Mount-Wright. This orebody was selected because the physical and chemical characteristics of the ore were very much similar to those of Lac Jeannine, as well as its huge reserves, estimated at more than one billion tons. In addition to the railroad extension, a mine, concentrator and related facilities were constructed and the new town of Fermont was created. Total investment for the Mount-Wright project exceeded $700 million and initial production commenced in 1976. Quebec Cartier is presently (1992) the leading producer and seller of iron ore in North America at 15,5 million tons and employs some 2,300 people.

Jan 1, 1993

By Roland Heersink, Charles H. Wells

This paper discusses how a mill uses off-site data hosting approach to effectively utilize an entire suite of advanced applications to optimize daily operations, without incurring the overhead of on-site systems, staff and support. Details of the solution are provided, together with a live view of actual plant operations. Security and authentication mechanisms are also outlined so that users may gain an appreciation of the actual security of the remotely hosted data. A number of Web-hosted software applications provide direct connectivity to the database offering rapid and deterministic response times to clients. A 24x7 help-desk is available to authorized users from any Internet connected device. The paper shows how mill management advantageously use wireless PDA's to view what is going on at anytime and from anywhere. It concludes with a summary of how the approach is being used to speed decision-making and capture spot market opportunities.

Jan 1, 2002

By K. H. McDaniel

People are our most valuable resource. It is as true today as any point in mining history as we face unprecedented personnel shortages aggravated by a workforce that is aging, significant generational gaps and difficulties recruiting younger professionals all amidst increasing global mineral demand. The educational system has a similar, but slightly contrary problem. Many historically strong mining engineering programs have died. Now, fewer mining oriented universities are trying to produce more students in order to meet the demand. Moreover, their situation is aggravated by a similarly aging workforce, a general lack of mid-career PhD?s with the interest and field experience to teach effectively, an extremely slow hiring and funding process, and an inability to be competitive against private industry compensation packages. The traditional instructional model, while not necessarily broken, is most certainly dated, and can penalize programs and students where schools do not have in-house expertise in a given topic. Mining companies, like Rio Tinto, have the opportunity, if not necessarily the obligation, to positively influence how this model works. Educational Partnerships may be the key. This paper will address some observations, and possibilities, associated with Rio Tinto?s efforts in this area.

Feb 23, 2014

By N. Paas

Diesel powered equipment has been operated in underground coal for more than 50 years. According to the Mine Safety and Health Administration (MSHA), there are approximately 3,000 diesel units operating in underground coal mines in the United States. This number is expected to reach 5,000 diesel units in 250 coal mines by the year 2000. Also, there are approximately 5,000 diesel units operating in metal/nonmetal mines such as trona, potash and salt mines: and more than 3,000 diesel units operating in Canada. This increased popularity of diesel powered equipment over trolley wire, electric trailing cable or battery powered equipment is because of improved safety, greater mobility, higher productivity and increased power of diesel equipment.

Jan 1, 1997

By Ed Schodowski

Wireless technology is a hot topic for anyone involved in the design, operation, maintenance or upgrading of mines or mineral processing plants because wireless technologies overcome barriers that have prevented many useful data inputs. Wireless communications can contribute to worker safety, satisfy environmental concerns, support plant security, track human and physical assets, and improve equipment maintenance. The cost structure of wireless is compelling and users can realize savings ? up to 90 percent less installed cost than wired instruments ? since wireless technology eliminates the need for expenses associated with cabling, engineering, construction and documentation. Many applications previously considered too expensive have become economically feasible with wireless. Two examples are continuous monitoring of safety showers to notify operators when one has been activated, and monitoring effluents to ensure environmental regulations are being met. In many cases, wireless transmitters can be installed where wired devices were too expensive to justify, or were not feasible due to physical or technical barriers. Examples include monitoring temperature measurements inside a rotating reactor or monitoring process variables in a tough, corrosive environment too challenging for a wired solution. Wireless also gives operating personnel mobility with the ability to communicate from remote or hard-to-reach zones. According to a recent Venture Development Corp. survey covering radio frequency (RF) of microwave industrial monitoring and control products, these features are contributing to the expected nationwide growth rate for industrial wireless applications of 19 percent annually from 2007 to 2012 (Taylor, 2008). At the same time, mineral producers have many questions about wireless systems including their applicability, reliability and security in this industry. Just what can wireless do? Is it secure and reliable? Can these instruments stand up to the rigors of the industry? Can wire-less technology provide the flexibility needed for mining applications?

Jan 1, 2009

By J. Hanna, H. R. Gonzalez

Discussion by N.L. Hargett Dear Dr. Hanna: As discussed in our phone conversation, we are enclosing a suggested revision to the paper, "Application of Bentonitic Clays in Suspension Fertilizer Formulations," published in MINERAL & METALLURGICAL PROCESSING, May 1990. The revision will replace the second paragraph in the article. The reason for the revision is that suspensions have decreased in market share since 1984 and at present comprise an estimated 25% to 30% of fluid mixtures. This represents 6% to 7% of all fluids and only 2% to 3% percent of all fertilizers. Based on national surveys conducted by the Association of American Plant Food Control Officials (AAPFCO), suspensions comprised an estimated 25% of all fluid mixtures in 1974, 33% in 1976, 35% in 1980, 40% in 1984, and 36% in 1988. Revision to "Application of Bentonitic Clays in Suspension Fertilizer Formulations." Suspension fertilizers are an important segment of the fertilizer industry in the United States. Suspensions allow higher concentrations of nutrients (N, P2O5, K2O) than clear liquid solution fertilizers. K20 content of solutions is limited to about 10%, while suspensions can contain more than 30% K2O. Suspensions can tolerate greater variations in temperature than solutions. In suspensions, if crystallization occurs, the crystals can remain suspended in a clay jell instead of settling as they would in solutions. Solubility is not a limiting factor in suspensions, since complete solubility of phosphate is not required. This allows a wider range of phosphate materials to be used. Also, materials commonly used in formulating suspensions are less expensive and more widely available than those for clear liquids (Getsiner et al., 1984).

Jan 1, 1992

By C. H. Pitt

A jet slurry apparatus has been constructed to test corrosive/erosive wear properties of grinding ball metal. Plain high carbon steel heat treated to a hardness of about 60 RC was used. Slurries of quartz and chalcopyrite ore concentrate were used as the jetting media. Weight loss due to pure corrosion was determined by the linear polarization technique and weight loss due to pure erosion was determined by jetting while cathodically protecting the sample. By comparing the total weight loss with the sum of the weight losses from pure corrosion and pure errosion it was found that there was a synergistic effect between corrosion and erosive wear. Erosive wear rates are given as a function of pH and mineral type.

Jan 1, 1984

By Jameel Menashi

Aqueous solutions of Na2Cr04 can be reduced with CO to produce hydrous Cr203 and NaHCO3/Na2CO3. CH3OH, HCOO and HCHO in the presence of CO2 also reduce Cr 6+ and yield similar products. It is shown that the rate of Cr6+ reduction can be represented by the expression -d[Cr6+]/dt=k[Cr6+)1/2[R] where [R] is the aqueous phase concentration of CH3OH, HCOO- or CO. With these three reductants, the activation energies for the reduction processes are comparable and are of the order of 100 kJ/mole. Rapid reduction rates are attained at temperatures in excess of 220°C and, with these three reductants, a green acid-insoluble readily filterable hydrous Cr203 is formed. With HCHO significant reduction of Cr6+ occurs at about 80-100°C and an acid-soluble violet modification of hydrous Cr2O3 is formed. The reduction process is reasonably selective: solutions of Na2CrO4 contaminated with Mo6+ and W6+ can be reduced to yield a Cr2O3 product with significantly reduced contaminant levels. These findings are utilized as a basis for a process for recovering chromium from secondary source materials.

Jan 1, 1984

By F. A. Renninger

The terms environment and environmental control, when used in today's context, generally imply to the average individual, something to do with pollution and pollution control. These latter terms, likewise, impart visions of fouled air and dirty water attributable largely to the industrial segment of American society. We have been conditioned, by various means, over the past ten years to equate environ¬mental control with pollution control. We have been trained to think of industrial environmental control programs as efforts conceived only to comply with one or more of the recently imposed pollution control regulations. Almost automatically we; approach consideration of environmental control with a degree of pessimism that is we assume that pollution prompted the control program. It is the purpose of this discussion to demonstrate that environmental control. at least as it exists and has existed within the crushed stone industry, involves far more than simply control or reduction of air and water pollution. It involves a dedication to the enhancement of each of the several "mini-environments" which together comprise the total world surrounding any given crushed stone operation. Environmental control, exercised properly, is an optimistic, constructive, forward-looking, enhancing type of activity. It is a function which has been, and should continue to be, willingly and expectantly undertaken by informed management personnel. In short, environmental control. is an activity from which both industry and society can and should benefit.

Jan 1, 1972

By C. N. Bensley, S. K. Nicol, R. Lamb, G. W. Kidd

Flotation circuits in the metalliferous industry recover high value concentrates from very fine (minus 0.lmm), low grade, slow-floating feeds. Flotation columns acting as final cleaners within these circuits offer the benefits of higher grade concentrates, reduced circuit complexity, improved control and reduced power consumption. By contrast, in the coal industry, these benefits have not been realised, principally because columns are not well suited to the treatment of conventional coal flotation feeds (minus 0.5m). However, this does not imply that columns do not have a place within the coal industry, rather that they must be applied in a role where all the unique advantages of column flotation can be of benefit. The development of a commercial scale column to recover discarded ultrafines from the Riverside preparation plant of BHP-Utah Coal Limited is discussed. Particular emphasis is placed on the column design features pertinent to the recovery of ultrafine coal. Pilot and commercial scale column performances are compared. The results of the commercial scale testwork indicate that a full installation at the 5.5 MTPA Riverside plant would annually recover additional coal worth $US 6.6M.

Jan 1, 1988

By R. E. Vivas

Goldcorp is one of the largest gold producers in the world with projects in South, Central and North America. Goldcorp?s flagship operation is Peñasquito, a world-class, poly-metallic deposit that started production in 2010 which is one of the largest mines in Mexico. Since the early stages of the project, Goldcorp has used the most advanced technologies available to maximize its value. However, the implementation of optimum mine plans has been challenging to put into practice. This is due to the fact that the mine operation involves more complexity than the plans usually reflect. This challenge is an industry wide issue that presents opportunities for improvement. This technical session discusses the mine planning methodologies and procedures used to connect long, medium and short term planning strategies in order to bridge the gap and produce optimum mine plans that can be practically implemented in the field.

Feb 23, 2014

By Joseph D. D?Annunzio

The report on cut and cover construction as assembled by the Organization for Economic Co-operation and Development covered 17 different countries based on a total of just under 400 individual replies of which about 30% of the replies were from the United States. In general, the review of replies to the questionnaire led to the impression that cut and cover construction is a very inadequate method which needed many improvements. This unfavorable judgment, however, resulted in the manner in which questions were asked rather than in the method itself, It can be concluded that the cut and cover construction method has proved itself as an excellent method and that it has reached a high degree of technological perfection, but inadequacies stilt exist, and for purposes of complete evaluation, comparisons with mining tunnelling methods should be carried out. The principal problem in cut and cover construction is the interaction during construction between the construction process and the existing use of the surface and subsurface environment. The greatest impediments to cut and cover construction have little to do with the physical works being constructed, but more with creating a site in which the work can be performed. Utility relocation, traffice maintenance, and protection of existing structures are major problems for the construction contractor, and too frequently receive insufficient attention in preconstruction planning and design. Some OF the areas in which research should be undertaken are as follows:

Jan 1, 1970

By S. K. Kawatra, H. J. Haselhuhn

"Fine-grained hematite ore can be concentrated by the process of selective flocculation and dispersion, which relies on proper reagent selection and control of water chemistry. While many previous studies have been performed analyzing the effects of different reagents on this process in a laboratory environment, this paper focuses on investigating the water chemistry within the process in a pilot-scale continuous deslime thickener.The pH, sodium concentration, calcium concentration and magnesium concentration were varied to determine their effects on the iron concentrate grade and recovery, and the phosphorus concentrate grade and rejection in the pilotscale selective deslime thickener. The ideal pH for the iron grade and recovery of the process using a starch selective flocculant was found to be 10.5. Phosphorus rejection, however, was increased at lower pH values. Minimization of sodium concentration was shown to improve iron grade, iron recovery and phosphorus rejection. Calcium acted as a nonselective flocculant showing higher iron recovery, lower iron grade and lower phosphorus rejection with increasing concentration. Conclusions could not be drawn from the experiments that varied magnesium concentration.The zeta potential of the solid-liquid interface of particles in each sample taken was also analyzed to show relationships between zeta potential and process performance. In all cases, a maximization of the magnitude of zeta potential correlated with increased iron grade and recovery. This supports the hypothesis that a higher level of dispersion enhances the selective flocculation and separation process.IntroductionThe United States produced 53.2 million metric tons out of the 3,000 million metric tons of concentrated iron ore produced worldwide in 2012 (Tuck, 2013). With this in mind, there has been a large increase in iron ore processing research (Bolen, 2014; Carlson and Kawatra, 2008, 2013; Halt and Kawatra, 2014; Halt et al., 2014; Haselhuhn et al., 2012a,b, 2013a,b; Liu et al., 2014; Manouchehri, 2014; Sandvik and Larsen, 2014; Semberg et al., 2014). Of the 53.2 million metric tons produced, roughly 8 million metric tons of hematite (Fe2O3) concentrate were produced using a process known as selective flocculation and dispersion (Cliffs Natural Resources, 2011). This process is the only economically viable method for concentrating low grade (< 40% Fe) fine grain (< 25µm liberation size) hematite ores. It is scarcely used due to difficulty in controlling the surface chemistry of the ore and high reagent costs (Department of Energy, 2001; Haselhuhn et al., 2013a). The process is highly dependent upon both reagent selection and precise control of the water chemistry during separation. This study shows the dependence of the process performance of a pilot-scale deslime thickener on the water chemistry in the feed slurry."

Jan 1, 2015

By P. Karimi, A. Akcil, A. Amini, H. Abdollahi

"In this study, cyanidation experiments were carried out on a massive sulfide ore sample, whose grades of the precious metals gold and silver were found to be 4.2 g/t and 311.9 g/t, respectively. Other elements in the ore were arsenic with average grade of 1,751.6 g/t; antimony, 619.7 g/t; zinc, 781.4 g/t; copper, 454.6 g/t; lead, 101.8 g/t; mercury, 324.3 g/t; and bismuth, 0.6 g/t. The first objective of test work focused on determining the best conditions for extracting gold from the ore, ground to less than 75 microns. Different influential parameters such as particle size fraction, cyanide concentration, pH and leaching time were investigated. The optimum parameters were found to be particle size fraction of less than 25 microns, cyanide concentration of 2,000 mg/L, pH of 11 and cyanidation time of 24 hours. In these optimum conditions, the highest gold and silver leaching efficiencies were 76.88 and 59.63 percent, respectively. In addition, roasting as pretreatment at a temperature of 700°C over a period of two hours was evaluated. Cyanidation testing of the roasted ore in the optimum conditions found increases in the gold and silver leaching efficiencies to 85.97 and 67.57 percent, respectively. Moreover, antimony extraction rose to 43.10 percent, from 23.73 percent without roasting.IntroductionGenerally, gold ores can be classified as “free milling” or “refractory,” depending on how they respond to cyanide leaching (La Brooy et al., 1994; Celep et al., 2009). While high gold recoveries (> 90 percent) from free-milling gold ores can be readily achieved, refractory gold ores are often characterized by low gold recoveries (50-80 percent) within a conventional cyanide leaching process (Rubisov et al., 1996; Adams, 2005; Celep et al., 2009). The presence of preg-robber components such as carbonaceous matter, sulfide minerals and aluminosilicate can further decrease gold and silver dissolution rates and recoveries. With the negative effect of the presence of preg-robbers, gold dissolution is considerably diminished in solutions with high cyanide concentration (Tan et al., 2005). In such refractory gold ores, gold particles may sometimes be occluded or included in the sulfide minerals, and pretreatment becomes necessary to break down the mineral structure to liberate gold for subsequent recovery. These ores are usually pretreated with an oxidizing process, after which gold and silver can be recovered by a standard cyanidation process. The main oxidizing processes available for refractory gold ores are roasting (LaBrooy et al., 1994; Angelidis and Kydros, 1995; Li et al., 2009; Karimi et al., 2010; Kyle et al., 2012), biological oxidation (Lawrence and Bruynesteyn, 1983; Komnitsas and Pooley, 1990, 1991; Deng and Liao, 2002; Ciftci and Akcil, 2010, 2013) and pressure oxidation (Mason, 1990; Murthy et al., 1992; Qingcui et al., 2009). In addition, ultra-fine grinding is being used in some plants for the liberation of gold and silver particles that are interlocked in the sulfide or silicate minerals (Celep et al., 2011)"

Jan 1, 2015

By Harold J. Schock

The cases of no auxiliary ventilation and ventilation with tubing were mathematically modeled, using a turbulent dispersion model. The scooptram that is used to load is modeled as a variable-speed, variable-strength source of pollutants moving in and out of the dead-ended drift. Model predictions are compared to experimental measurements. A parametric analysis was performed to determine the effect of exhaust pipe location and time spent out of the drift, as well as to determine if a relationship existed between CO2 and NO levels. It was concluded from this analysis that when modeling a load-haul-dump cycle, it is necessary to use a model that has the capability of predicting changes in source strength as well as source location. It was also determined that four relevant factors include effective heading height, apparent longitudinal diffusion coefficient, transverse concentration gradient at the face, and average dispersion width of the exhaust jet. As these factors change with heading geometry and ventilation configuration, they were determined experimentally, Carbon dioxide was used as a tracer to calibrate the model; since, knowing the fuel flow rate, it is possible to calculate CO2 production. The above four factors in the computer model were calculated using a regression analysis, comparing predicted local concentrations to measured local concentrations. The model was then verified after this calibration process using additional experimental results. With the calibrated model, it is possible to predict pollutant concentrations at any location in the heading using an engine map and the previously calculated flow field. A parametric analysis shows that the exhaust pipe location can have a significant impact on operator exposure to exhaust gases. It was also shown that NO concentration varies directly with C02 levels. Predictions using the dynamic model are contrasted with constant source strength (pollutant flow rate) results. An analysis of these predictions for computing time-weighted average NO shows the dynamic model predictions of operator exposure to this pollutant to be less than one-half of the value predicted using a constant source model.

Jan 1, 1981

By J. F. T. Agapito

Stability in Exxon&apos;s Colony Pilot Mine in the Piceance Creek Basin, Colorado has been monitored by periodic pillar stress-determinations End roof-to-floor convergence measurements since 1971. Pillar failure has caused marginal stability in some areas of the mine. Measurements taken during the process of failure provided valuable information on the in-situ pillar strength and long-term behavior of the mine structure. Four pillars were reinforced by 32 mm (1-1/4 in) diameter tensioned grouted bolts to increase long-term stability in the northern area of the mine. Stability of this area is necessary because future plans envision its use as an exit/access and ventilation exhaust. Computer analyses were performed to help evaluate the effect of pillar reinforcement on long-term stability. Results indicate that bolting is particularly useful in stabilizing failed pillars, but its effects are significant only in the immediate area of the pillar. The projected significant decrease in deformation of two extensively failed pillars near a main entry indicates that bolting reinforcement will assist the long-term stability of the opening.

Jan 1, 1985

By B. Pollack, L. G. Stevens

INTRODUCTION In other chapters of this volume many of the important technical aspects in the design of concentration and dewatering circuits have been discussed. This chapter will deal with the steps necessary to bring that information together in order to produce the specifications necessary to purchase the equipment and complete the design. It deals with the plant as a whole rather than just concentration and dewatering, since the steps are essentially the same. Prerequisites to Engineering Design Feasibility studies will have been completed and design parameters established prior to the start of the engineering design stages for a metallurgical plant. The data base for the feasibility studies will have included laboratory and/or pilot plant test work, historical data, proposed plant site data such as climatology, topographic mapping, geological and geotechnical information. These studies will have established the general project design criteria as well as the process design criteria leading to the preparation of preliminary flowsheet ( s) and/or alternative process flowsheets. These will have incorporated metallurgical and material balances, allowing identification of major equipment items, and development of preliminary plant site plot plans. Preliminary technical and economic assessments and recommendations will have been prepared during this phase for Owner&apos;s review and evaluation of the technical, physical, and cost effectiveness of the overall project and its component process, process facilities, and supporting facilities elements. After Ownert s approval and decision to proceed, the engineering design can be initiated, using the above information as the basis. Engineering Design Phase The engineering design of metallurgical plants and their elements are generally developed in two sequential stages, namely: (1) Basic ("Front end") Engineering Design (2) Detail Engineering Design Figure 1 relates these engineering stages to the entire program from feasibility through construction.

Jan 1, 1986

By Peter Zhang, Daniel Su, Bo Hyun Kim

Shale gas wells drilled in longwall chain pillars are influenced by longwall mining. Longwall mining on each side of the chain pillars can create overburden movements and induce deformations in gas well casings. If the deformations result in a casing breach, intrusive shale gas could leak into the longwall mine with serious safety consequences. This study concerns five shale gas wells in the chain pillars between two adjacent longwall panels in the Pittsburgh coal seam under a cover depth of 670 ft and a mining height of 7 ft. The gas wells were constructed with typical casing design, but a casing cementing alternative with uncemented production casings was practiced. Four production casings were uncemented, and one production casing was unintentionally cemented with good quality cement to a 535-ft depth and low-quality cement stringers from a 444- to 535-ft depth. The longwall faces passed by the shale gas wells as each adjacent longwall panel retreated. Production casings were surveyed by a multi-finger caliper after each panel was mined. No deformation was detected in the four uncemented production casings, but small deformations were detected in the partially cemented production casing. The maximum measured deformation in the cemented production casing was 0.05 in. after first panel mining and 0.06 in. after second panel mining. The casing deformations were also predicted by the FLAC3D model set up on site-specific overburden geology. The predicted deformations were in good agreement with the measurements in terms of deformation locations and magnitudes. All five shale gas wells resumed normal production after being temporarily plugged during the period of mine-by. This study provides a successful demonstration of the effectiveness of a casing cementing alternative for decoupling production and intermediate casing, and thus minimizing the influence of longwall mining in the shale gas wells drilled through longwall chain pillars.

Jul 1, 2023

By Michael H. Inglis

The Technology Application Center, in conjunction with the U.S. Bureau of Mines Liaison Program, is studying the use of Landsat data for the monitoring of coal surface mine reclamation activities. Landsat may provide sufficient information to reduce the number of on-site inspections now required. The focus of the project has been the Navajo Coal Mine located in north- western New Mexico and operated by Utah International, Inc. On October 15, 1977, a field team recorded spectral measurements at the mine during the time of Landsat&apos;s overpass and a corresponding aerial photographic flight. Training sets were selected from the ground and aircraft data representing vegetated, graded, ungraded and natural environments. A supervised classification of the data was performed by the Stanford University Remote Sensing Laboratory then correlated to aerial photos and mine maps. The results, to date, have been very encouraging.

Jan 1, 1979

By Donald P. Tuchman, Emanuele G. Cauda, Steven E. Mischler, Elaine N. Rubinstein, Jay F. Colinet

The PDM3600 and PDM3700 are two closely related person-wearable dust monitors manufactured by Thermo Fisher Scientific. Both are based on tapered element oscillating microbalance technology and provide nearly real-time, mass-based readings of respirable dust concentrations. From a monitoring perspective, the primary difference between the models is the PDM3600 has an integrated cap lamp with attached inlet, while the PDM3700 has no cap lamp and a revised inlet attaches to the worker’s lapel. Using coals of varied origin and employing a wide range of concentrations, side-by-side measurements from these instruments were collected under controlled laboratory conditions and then compared. By use of ordinary least squares and weighted least squares regression methods, followed by mixed model analysis, results suggest there is no statistically significant or practical difference in instrument performance. The two monitors are equivalent for the field dust concentration measurements for which they were designed.

Feb 28, 2024