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By John E. Husted

Universities have education as their primary purpose. This appears to be an innocuous statement with simple meaning. In an age of conflicting semantics, however, cords and meanings are often lost or changed. The term education is often broadly expanded to encompass any form of learning process, or the accumulation of knowledge, and even to the beneficial application of knowledge to man's problems, hence one find that education in universities is not solely the formal process of texts, lectures, recitations, and testing by a batch process known as class room teaching. Despite critics of education batch is spelled with an "a", instead of an "o" - at least we hope so If one defines teaching as causing to learn, then the learning objectives may necessitate a variety of approaches within the teaching concept and research is among those favored at the graduate and some undergraduate levels. Research has been among the glamour words and certain fields such as oceanography and space science have had more than their share of glamour. Unfortunately, industrial mineral research has not had the competitive drawing power of enamoring students of the "note" generation in terms of glamorous accomplishment. Research today usually requires sophisticated equipment and such equipment is expensive, both for initial purchase and operation. Again, administrations, be they industrial, government, or academic, usually require

Jan 1, 1970

By J. R. Koehler

Mining practices at the Sunnyside Mines, Sunnyside Coal Company, Sunnyside, UT, have been documented by U.S. Bureau of Mines researchers to preserve the extensive history of yield pillar-based longwall gateroad system evolution on the property. An overview of the historical mining conditions, practices, and innovations that resulted in the evolution of the two-entry yield pillar gateroad system currently employed at Sunnyside was developed from interviews of 30 long-time Sunnyside employees. Employing yielding chain pillars at Sunnyside virtually eliminates tailgate pillar bumps and contributes to reducing face bumps. Limiting the overall width of the gateroad system benefits bump control and especially, roof and floor stability.

Jan 1, 1994

By P. B. Moran, J. W. Rozelle, J. Forbort

"The Mount Todd gold mine is located approximately 50 km (31 miles) north of the town of Katherine in the Northern Territory (NT) of Australia just off the Stewart Highway, and was operated in the 1990s until 2000 (Fig. 1). After cessation of mining operations, meteoric precipitation and acid rock drainage (ARD) associated with surface water runoff continued to report to the retention ponds across the mine site. In 2000, the mine site entered receivership and the NT government became responsible for the care and maintenance program. In 2006, Vista Gold Corp. (as Vista Gold Australia) acquired the rights to resume exploration on the mine site without the financial responsibility of the environmental liability. In January 2007, Vista Gold assumed the care and maintenance activities on behalf of the NT government, with the environmental liability remaining with the NT government, with the goal of reinitiating mining operations. A critical path component of the planned upgrades to the existing mine/milling facilities and infrastructure was the development of a cost effective treatment and dewatering program for the approximately 11 GL (2,900 million gal) of ARD stored in the Batman Pit (RP3), which has a maximum capacity of approximately 12 GL (3,200 million gal). The Batman Pit must be dewatered in order for Vista Gold to restart mining activities. The Batman Pit Lake had reached a maximum water depth of 104 m (341 ft) when Vista Gold initiated water level monitoring. It is important to note that the ARD water in the Batman Pit has been pumped into it from 2000 to 2012 under an NT government-approved environmental control program.The Batman Pit has virtually no connection to the local ground water regime due to the intensive silicification that accompanied the mineralizing event. In October 2012, just prior to treatment, the pit lake profile was characterized by uniform acidic pH (approximately pH 3.2) and oxic conditions (dissolved oxygen greater than 7 mg/L with depth (Fig. 2). The temperature decreased by approximately 4 °C (39 °F) between the lake surface and approximately 20 m (66 ft) deep, and remained near constant with increasing depth. This temperature difference is believed to be associated with an existing shallow mine bench at approximately 20 m (66 ft) deep around the perimeter of the pit. Similarly, electrical conductivity, an estimate of total dissolved solids, decreased by about 85 microSiemens per centimeter (µS/cm) from 2,800 to 2,715 µS/cm between 10 and 20 m (33 and 66 ft)."

Apr 1, 2016

By F. Carew

Accurate knowledge of what mass and grade is to hand and where it is stored is key to mine efficiencies and overall profitability. In order to make the right decisions and align production with stockpile capacity, feed and contract demand, a clear and accurate view from production through blending and processing is required. The use of a mine production management solution can provide you with a high degree of confidence in and visibility into validated data as well as auditable and traceable material movements, activities and surveys. A robust calculation engine enables mass and grade changes to propagate to material movements and stockpiles to ensure you are getting the most accurate view at all times. Tracked changes in material balances can be readily incorporated in revised production schedules to close the loop. The availability of accurate, timely information, coupled with predictive trend indicators, is a significant advance in narrowing the gap between claimed and planned production that is common to many mines, regardless of commodity. This paper provides an overview of a Mine Production Management System (MPMS) and explains how the system helps address the challenges listed above.

Jan 1, 2011

By A. Wright

Gold Fields Mining Corporation is presently evaluating gold mineralization beneath thick, wet alluvium at the Chimney Creek Project, Nevada. Contamination of reverse circulation samples has been visually apparent since drilling began in the area. Tests have shown that, while contamination can affect assays, reverse circulation holes appear to define mineralized zones almost as well as the diamond drill holes. To improve reverse circulation sample integrity several techniques were tried including a stiff-mud injection system but with limited success. Diamond core drilling continues to be used in conjunction with reverse circulation drilling to further delineate the mineralization.

Jan 1, 1991

By Behrouz Tehrani

The size, complex issues, and requirements to construct large number of tunnels, for a single project, expeditiously, and without exceeding the overall project budget, a program Construction Management (CM) team is highly recommended to be selected early during design process to provide guidance/direction relative to contract packaging and scheduling. This paper is not focused on the project itself, however, the emphasis is on experiences gained from the project. Wishing that some of the strategies described in this paper will be of value to owners of underground project.

Jan 1, 2008

By H. EI-shall

The conventional beneficiation scheme for Florida phosphates involves reverse flotation with an intermediatory acid scrubbing step. A single reagent flotation process, using fatty acids or amine as the collector, would eliminate the scrubbing step along with the other flotation step. This can not only simplify the process flowsheet, but also result in reduced reagent costs. The potential of single reagent flotation of Florida phosphates using fatty acids as the collector was examined in this study.

Jan 1, 1993

By S. C. Sun

Pennsylvania has ample reserves of high-alumina clays which are potential sources of alumina, but many of these clays contain large amounts of iron, which makes them unsuitable for treatment by acid processes(1). The purpose of this investigation was to determine the optimum conditions for the selective hydrochloric acid leaching of iron (2-4) prior to the sulfuric acid extraction of alumina from Pennsylvania ferruginous high-alumina clays. This was accomplished by first testing the iron-bearing minerals and the clay minerals most often encountered in Pennsylvania clays to determine their rate of dissolution in hydrochloric acid solutions. The results of individual minerals were then based for leaching Pennsylvania clays with a 19% hydrochloric acid solution at the boiling point of the acid for approximately 30 minutes to achieve as high as 90% iron removal and only 2-5% alumina losses.

Jan 1, 1968

By W. X. Wang

In the mining and quarry industries, rock fragments are often transported by conveyor belt. To estimate the qualities of the rock fragments (i.e., size distribution and shape), an operator must take samples from the conveyor and manually perform a sieve analysis, which is time-consuming and tedious. Alternatively, an image-analysis system can be used to monitor the fragment quality on a fast moving conveyor belt. However, images of fragments on a fast moving belt vary to such a degree that the quality of any two successive images are not the same, and some of the images are of such poor quality that they are unrecognizable by human eyes. If poor-quality images are directly analyzed by a segmentation algorithm, the analysis will not be satisfactory. To resolve this problem, it is necessary to use an image-classification pro-gram for the automatic selection of fragment images with good quality. Because of this need, an image-classification program was developed and tested both in the laboratory and in the field. Testing of the system on different types of fragments showed that the system works reasonably well.

Jan 1, 1996

By A. Ghosh

Commonly used predictors of ground vibration from blasting, being linear in log-log plot, do not model the underlying physics of wave attenuation. Amplitude of the wave decays with distance due to geometrical spreading and inelastic attenuation producing a nonlinear carve in log-log scale. The nolinear decay of seismic waves has also been observed from non-explosive sources, such as, pile driving, drop hammer, traffic, etc. The improved predictors, by explicitly taking these two mechanisms into consideration, model the data trend extremely well at all distance ranges. Actual field data from different studies have been used to validate the improved models.

Jan 1, 1991

By K. F. Unrug

The identification of the major subsidence areas in the Western Kentucky Coal Field has been made to distinguish the subsidence phenomena on the basis of geographical location Further, this identification process is based upon selected critical geological, topographical, and mining features in the coal fields. The proposed identification of the regions is derived from a comparison of the subsidence potential in a particular area. The most likely severe subsidence areas are compared to those with the probable low subsidence severity. The combination of certain geological and mining parameters involved allows for the derivation of a classification of the subsidence potential. It is recommended that further site specific studies should be performed on this area.

Jan 1, 1986

By S. D. Thompson

An AIME transaction by P.L. Allsman (1960), "Analysis of Explosive Action in Breaking Rock," contains many useful concepts applicable to blast design. Of special interest was the derivation of a heave blasting burden formula, which is important in establishing the maximum burden. Unfortunately, its derivation contains a fundamental error and then a compensating one. This formula was: [ ] The derivation used the impulse-momentum principle, with a 0.3 m thick (1 ft thick) radius of rock mass being acted on by an explosive impulse. However, the rock weight was not converted to mass by dividing by the gravitational constant. This mistake can be verified by checking the units in the formula, which resolve into m%-sec instead of meters. Adding the gravitational constant corrects this: [ ] If the minimum velocity is now taken as 0.3 m/sec (1 ft per sec), as was recommended, excessively large burdens result. Any appropriate rock velocity should be capable of throwing the rock mass a minimum distance so that the swell needed for breakage can occur. Unless the burden is extremely small and the bench height is very high, it is unlikely that a velocity of only 0.3 m/sec (1 ft per sec) will be sufficient. A review of the literature indicates that average rock velocities observed by camera studies typically range from 15 to 30 m/sec (50 to 100 ft per sec) (duPont deNemours and Co., 1977; Tansey, 1979). On this basis, a minimum rock velocity of about 15 m/sec (49 ft per sec) would be expected and not 0.3 m/sec (1 ft per sec). When a velocity of 15 m/sec (49 ft per sec) is inserted into the corrected formula, the results approximate those of the original formula with a velocity of 0.3 m/sec (1 ft per sec). The errors were approximately self-compensating [ ] References Allsman, P.L., 1960, "Analysis of Explosive Action in Breaking Rock," Transactions, AIME, Vol. 217, pp. 475-476. E. I. duPont deNemours and Co., 1977, Blasters' Handbook, 175th Anniversary Edition, Dupont, Wilmington, DE, pp. 233. Tansey, D.O., 1979, "The DuPont Sequential Blasting System," CIM Bulletin, Vol. 72, July, p. 80. Thompson, S.D., 1981, "Critical Review and Revision of Surface Blasting Practice," MS thesis, West Virginia University, pp. 308-316.

Jan 3, 1985

By J. A. M. Cano

Since the beginning of operations at the pellet plant at Ponta Ubu ES, Samarco Mineração SA has produced pellets for direct reduction and blast furnace processes. Of the total amount of pellets produced from 1977 through 1993, 55% are used in the blast furnace, about 45 Mt (49.6 million st). The principal components of pellet gangue are calcium oxide, magnesium oxide, silica and alumina. They should be added in adequate quantities to guarantee the mechanical resistance of the fired pellets under blast furnace conditions. Over the years, the pellets produced by Samarco had a silica content between 2.5% and 2.8% and varying binary basicity preferably between 0.8 and 0.85. On the other hand, the increasing amount of industrial waste in siderurgical plants caused by the increase of steel production has caused some countries to put into practice methods to reduce the volume of slag produced in the blast furnace. This paper’s goal is to find an alternative for decreasing the amount of slag produced in the blast furnace. It is possible to decrease pellet gangue by decreasing the silica content to about 2%, leaving the metallurgical properties and quality of pellets unaltered. For this work, Samarco pellets were used with SiO2between 2.5% and 2.8%, pellets with high silica and pellets with SiO2 between 2.0% and 2.3% low silica. Both were partially fluxed by the range of varying basicity CaO/SiO2from 0.8 to 0.95 during production.

Jan 1, 1995

By S. G. Malghan

Steel consumption forms a significant part of the operating cost of a minerals processing plant. An estimated one-quarter billion kilograms of steel in the United States and over one-half billion kilograms in the world are consumed each year in wet grinding alone. The depletion of ore grades and the necessity of finer grinding of abrasive ores are expected to increase the steel consumption even higher. Through continued research and development by the mining industry and the suppliers of steel products several remedies to reduce steel consumption have evolved. This paper critically reviews the mechanisms involved in steel wear, and currently available methods, materials and operating conditions for reducing steel consumption. Particular attention is given to liner design modifications and substitution of steel liners with rubber liners.

Jan 1, 1981

By S. E. Phillipson

Four massive pillar collapses in limestone mines, and one in a marble mine, occurred between 2011 and 2021 in benched areas at the Appalachian physiographic province. We characterized the rock mass at 43 limestone mines using the Geological Strength Index and, by plotting the results on a physiographic relief map, determined that GSI values between 55 and 70 preferentially occur in the Appalachian and Ouachita Mountains, which were subject to deformation during the Ouachita and Alleghanian Orogenies. Limestone mines located in formations of similar age in the Interior Plains, where deformation was less developed, are characterized by Geological Strength Index values over 80. We present the results of pillar strength calculations that incorporate the Geological Strength Index from mines that experienced massive collapse, as well as from mines with benched areas that did not collapse, to demonstrate the negative effect that a jointed rock mass has on pillar stability. We suggest that pillar designs, particularly those in which benching will be incorporated, should include allowance for rock mass quality. Because of the preferential dominance of lower GSI values in the Appalachians, we further suggest that pillar designs in this environment may require additional engineering assessment, especially where benching is intended. Lower GSI values may often translate into greater overbreak, which results in loss of pillar volume, corresponding wider back spans, and a decreased width-to-height ratio.

Jun 25, 2024

By S. A. Bortz

IIT Research Institute has initiated several multi-sponsored research programs. In this paper the methods for developing four of these programs are discussed. In general, a broad area of investigation must be proposed to interest a spectrum of different industries. The work must not touch upon proprietary data and will probably involve a number of scientific disciplines. Thus, the problem to be solved will attract sponsors who need to know more about the area under study but do not wish, as a single company, to commit the resources required to obtain the necessary know-how for their needs. The paper draws on the background of four IITRI multi-sponsored projects: Size Reduction, a study of grinding of material to reduce their particle size; Melt-Formed Ceramics Research, a method of producing dense, polycrystalline ceramics using glass forming methods; Binders in Ceramic Processing, which addresses the problems associated with the use of organic aids for ceramic processing; and a Study in Air Pollution Technology, a program to review and assess pollution control equipment for current and future applications.

Jan 1, 1984

By W. D. Hausel

Archean supracrustal rocks of the South Pass greenstone belt of western Wyoming have been the State's most prolific source of gold and iron ore. Actual gold production statistics are incomplete, but as much as 400 to 500 thousand ounces may have been mined with some silver and tungsten as a by-product. Iron ore was also mined from the greenstone belt for 22 years, and production totaled more than 90 million tons. Immediately south of the exposed greenstone belt in the Oregon Buttes area, Tertiary boulder conglomerate, which has been eroded from the granite-greenstone terrain, may contain a gold resource of 28.5 million ounces (Love and others, 1978). The amount of gold placered from stream alluvium derived from these Tertiary conglomerates is unknown.

Jan 1, 1986

By K. Zabrusky

"Wireframe construction is an integral part of resource estimation. Wireframes control domaining of samples and data for geostatistical analysis and grade estimation. They may also provide 3D representations of lithology and grade domains. Thus, the way in which a wireframe is constructed has implications throughout the resource estimation process. Proper construction technique and understanding of wireframing processes should be a high priority in a model workflow. Herein is presented an overview of two main categories of wireframes: implicit and explicit. Construction differences between these two types are highlighted. Factors affecting the choice between the two wireframe types will be discussed, including data quantity, data distribution, and sampling technique. Deposit geometry also plays an important part in wireframe construction. The role of geologic knowledge, cross section orientation, and deposit type in regards to wireframe construction will be discussed. The effect of wireframe type on resource estimation will be examined. Finally, best practices for creating meaningful solids that contribute to a reasonable grade estimation are outlined. INTRODUCTION Wireframes are essential to many types of resource estimations. They provide a way to delineate a deposit into various domains. Domaining can be done by lithologic or geologic units, structures or structural zones, or by grade. Domaining is important for geostatistical analysis and grade estimation of a deposit. The purpose of domaining is to analyze and estimate like data with like. Grade distribution patterns may vary by lithology or by proximity to or existence within structural zones. Properly constructed wireframes are therefore a fundamental necessity to a properly executed geostatistical analysis and resource estimation model. The choices made in construction of wireframes have a trickle-down effect on the entire model and should be made according to best practices for the deposit type at hand.TYPES OF WIREFRAMES Explicit The term “explicit wireframe” is used in this paper to indicate wireframes that are constructed by the modeler. This usually involves the modeler drawing the wireframes “by hand”, e.g. still utilizing some sort of computer aided drawing software, but with the modeler making all decisions about the size, shape, and positon of the wireframe. These wireframes are drawn based on some type of key variable that the modeler determines is important to their system. Often, this key variable may be a lithologic unit that controls mineralization, an observable structural zone, or a grade cutoff. Explicit wireframes are generally constructed as a series of shapes drawn on 2D planes or cross sections that are then connected into a 3D shape. Figure 1 shows an example of an explicit wireframe that was drawn based on a grade cutoff on 2D sections (Figure 1a), then joined into a 3D shape (Figure 1b)."

Jan 1, 2015

By J. C. Yingling, R. J. Sweigard, P. W. Conrad, J. M. Ringe, D. H. Graves

Much of the land reclaimed since enactment of the 1977 Surface Mining Control and Reclamation Act is over-compacted. Research has shown that excessive compaction in replaced growing media is detrimental to establishment of trees. If trees are to be grown on reclaimed surface mined sites, something must be done to alleviate this excessive compaction. Dry bulk density and penetration resistance are two soil parameters that can be used to indicate the level of compaction in reclaimed growing media. The University of Kentucky has developed test cells on reclaimed sites at a surface mine in eastern Kentucky to determine the impact of tillage (ripping) on soil compaction and tree survival rate. The ripping methods being evaluated include shallow tillage using conventional farm equipment and deep tillage using a dozer with a ripping arm. The impact of organic soil supplements on soil physical properties and tree survival rates is also being evaluated at the site. The organic soil supplements being evaluated include application of hardwood bark and application of straw and mulch. Each test cell has been planted with various species of trees, and for the first two years, data have been collected at these test cells for soil dry bulk density, penetration depth and resistance, and survival rate of trees. These data are currently being correlated to determine how ripping and the application of organic soil supplements affects the relationship between soil compaction and tree survival rate.

Jan 1, 2002

By S. R. Dindarloo

"Truck-shovel systems are the dominant material loading and haulage machinery in open pit mining operations. Optimal selection, sizing, and allocation of this capital intensive equipment is highly desirable for both achieving production targets and improving the mine’s economics. In this study, discrete event simulation technique was applied for modeling material transportation in Golegohar open pit iron ore mine in Iran. Direct observation of the material loading and haulage for duration of three months resulted in statistical modeling of the operation in the form of probability distribution functions. These probability models were used as the inputs of a stochastic simulation model constructed in GPSS/H simulation language. The model was validated through comparison with the actual operation and was used to test different what-if scenarios and sensitivity analysis of the current system. Some modifications in the number of trucks, shovels, and dispatching strategies were proposed. Simulation resulted in considerable improvements in the mine’s production and economics.INTRODUCTION There are three different mechanisms of discrete, continues, and hybrid material transportation in open mines, including but not limited to: i) in-pit crusher and conveyor belts (hybrid), ii) slurry piping (continues) and iii) truck-shovel system (discrete). Although, each mechanism has its advantages, the truck-shovel system is the dominant method of material loading and handling in open pit mines owing to its high production rate, excellent flexibility, relatively low operating and capital costs, and good maintainability. General objectives of optimal equipment selection include: i) meeting the long and short term requirements of production rates, ii) human & equipment safety, iii) environmental protection, and iv) economic operations (Figure 1).The two most important decision factors on a truck-shovel system selection and sizing are the equipment geometry and size. Geometry (equipment width, weight, turning radius, swing angle, etc.) is mostly controlled by mine’s designs and layouts, as well, as operational constraints. After selection of a favorable geometry based on the constraints; the next step is to select the equipment manufacturer. Once the geometry and manufacturers are selected; the next step is to decide on models (e.g. Bucket size) and required number of each unit"

Jan 1, 2015