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By C. C. Harvey

Asia is experiencing a growth market for industrial kaolins for use in ceramics, paper, plastics and other market sectors. Export and import data for the Asian countries reflects this growth with the Peoples Republic of China as the major exporter of clays and Japan the major importer. The growth in tonnage and product sophistication of kaolins produced on Belitung in Indonesia is typical of developments that are taking place in many locations in Asia. This region therefore presents opportunities for mineral processors and a challenge for the exploration geologist, the mineral processing engineer, the mineral economist and the marketing specialist.

Jan 1, 1996

By S. Yerel

Block cutter machines have been extensively used in natural stone industry, which is a sub-section of mining industry. In this study, the costs occurring in plate losses cut from Bilecik beige marble with a circular saw block cutter machine have been predicted using Statistical Process Control (SPC) techniques. One of SPC techniques is Shewhart control charts such as mean control chart. These charts have been efficiently at determining the plate losses. The costs occurring in plate losses have been calculated by using the result of Shewhart control chart. Finally, this study presents the necessity and usefulness of SPC techniques in assessment of natural stone industry.

Jan 1, 2010

By M. J. Meulendyke

An extensive program of marked ball wear testing (MBWT), laboratory corrosion studies, and worn ball surface analyses has been used to gain insight about the role of corrosion in the overall wear process. In some environments, localized corrosion is observed; the actual wear mechanisms in such cases are pitting/spalling and abrasion. Factors affecting the occurrence of pitting include the abrasiveness of the ore, corrosivity of the slurry, corrosion resistance of the media, and galvanic coupling effects. Elimination of pitting substantially improves overall wear resistance. When pitting is not observed, the contributions of general corrosion are significantly less.

Jan 1, 1984

Underground testing was carried out by Ingersoll-Rand, Inc., under contract to the Bureau of Mines to determine the effectiveness of a machine-mounted scrubber system for ventilating the face during an extended advance. A continuous miner equipped with an integral flooded-bed dust scrubber system was instrumented with methanometers and Real-time Aerosol Monitor (RAM) dust monitors. Methane and respirable dust data were collected at brattice setbacks of 7.5 m (current operating distance), 10.5 m, and 15 m (blowing ventilation) during production shifts. Results showed that a suitable machine-mounted scrubber system can adequately ventilate the face at brattice setbacks up to 15 m. No deterioration in ventilation performance was observed as brattice setbacks were increased from 7.5 m to 15 m. The scrubber system effectively controlled face methane levels at large setbacks, though respirable dust levels increased as much as 33 pct at the operator's cab at setbacks greater than 7.5 m.

Jan 1, 1986

By J. Marbeau

In this paper, a geostatistical study of the North Butte roll type uranium deposit is presented. The geostatistical procedure applied takes into account the varying direction of the roll front for reserves calculations. For variogram calculation, the roll front is unfolded thereby allowing estimation of the variogram in directions parallel to and perpendicular to the roll front. Variograms calculated in unfolded space show strong directional anisotropies consistent with the anticipated configuration of the deposit.

Jan 1, 1991

By A. A. Campoli

A stress control design strategy was developed to minimize the explosive failure of highly stressed pillars, during room-and-pillar retreat mining conducted between stiff immediate roof-and-floor strata. A confined core coal pillar strength model was based on in-mine geotechnical evaluations of successful room-and-pillar and longwall bump control designs. Tributary area and linear shear angle approaches were used to estimate development and gob side abutment pillar loads for supercritical section widths. Subcritical width sections separated by barrier pillars to control stress within total extraction panels were optimized with the boundary element program MULSIM/NL.

Jan 1, 1994

By W. Nazarewicz

The introduction of continuous papermaking in the early 1800's was the beginning of the industry as we know it today. Since that time, the majority of the paper produced has employed an acid process. However, in the mid 1960?s, European producers began a transition to an alkaline papermaking process. Early European mill conversions to alkaline papermaking begun in the 601s, accelerated during the 1970's influenced by the dramatically higher cost for OPEC energy as well as the high cost of fiber and imported filler clay.

Jan 1, 1986

By W. P. Barnett

In 1988, the U.S. Department of Energy's Pittsburgh Energy Technology Center identified three coal cleaning options for achieving flexible environmental control strategies aimed at reducing energy-related SO2 emissions. These are selective agglomeration, advanced froth flotation, and advanced cycloning. Each technology relies on maximum liberation of pyrite and other mineral matter through feed coal comminution to fine and ultrafine sizes. Research projects designed to expeditiously develop each of these technologies to the point of commercial viability were initiated. This paper will present the status of these projects and the application potential of each technology to coal beneficiation.

Jan 1, 1992

By K. Lang

A test section of the upper most lift and underlying lifts of a large scale copper heap leach operation was instrumented and monitored with advanced wireline geophysics, fiber optics and resistivity electrode arrays. Elemental Capture Spectroscopy (ESC) copper measurements, resistivity measurements from an Array Induction Tool (AIT), electrical resistivity tomography (ERT) and distributed temperature sensing (DTS) with fiber optics provided integrated near real time data about the performance of the heap. During the leaching cycle, ECS provided continuous vertical measurements of copper in the upper most and underlying lifts in the test section of the heap and was used to generate a copper recovery curve. ERT inversion modeling provided high resolution 3D resistivity measurements, which were used to evaluate moisture distribution. DTS measurements of temperature were used to track the PLS front and calculate velocity. AIT induction provided highly precise bulk resistivity measurements. In-situ samplers provided PLS chemistry at multiple points. Properly integrated monitoring data can provide the heap leach operator with information that can be used to evaluate the hydrodynamics and metallurgy of the leaching process in near real time. Problems in the heap, such as pooling, channeling, longer lag and breakthrough times, excess acid consumption, increased solution in inventory, toe saturation and slope stability can be detected in near real time with the in-situ measurements evaluated.

Feb 23, 2014

By Alvaro Veizaga, Samuel Cuellar

In recent years, Industry 4.0 has generated a change in the way companies in various industrial sectors design, produce and deliver products and services, and is focused on the interconnection of systems, the advanced access and management of large amounts of data in real time, and the implementation of emerging technologies such as the Internet of Things (IoT). Artificial intelligence (AI), machine learning (ML), digital twins (DT), robotics, virtual and augmented reality (VR/AR), among others [1]. DTs are accurate and dynamic virtual models that replicate physical systems, where it is possible to simulate and optimize operations before implementing real-world changes [3]. These features make it possible to reduce investment costs, minimize risks and improve strategic decision-making. These benefits are of utmost importance for tailings storage facilities (TSF), since they are facilities aimed at the safe storage of tailings and with the constant need for growth [4]. This paper evaluates the applicability of a DT in a TSF from a conceptual perspective, providing the advantages of its implementation, but also the barriers identified in the industry based on the authors’ experience.

Feb 1, 2025

By Alex Stewart

Most iron bearing ores treated by the R=N Direct Reduction Process yield products lower in phosphorus than the initial ores. The sulfur is also removed and generally is in the range of 0.02 to 0.05 percent in the final R=N product, independent of the sulfur content of both the ore and carbon fuel used. The mechanism and thermodynamic justification of the principal reactions leading to the removal of both phosphorus and sulfur and the control of sulfur in the iron concentrate produced are discussed and supported by the results of laboratory experiments. In substantially all iron ores (containing up to 4% sulfur as sulfate) and solid carbon fuels (containing sulfur from 1 to 8%) tested, the rejection of sulfur has been in the order of 90-95%, with not more than 0.02 0.05% sulfur in the final metallic iron product. With respect to phosphorus-bearing iron ores ranging up to 0.70% P205, the rejection to tailings has been in the order of 70-95%, resulting in not more than 0.03 - 0.07% phosphorus in the final product.

Jan 1, 1958

By Frank Sames

A recently developed model is used as a tool to optimize blast designs based on the continuing combination of full scale blast assessment and performance prediction. The use of this tool has allowed to evaluate present blasting practices and proposed designs through a better under-standing of the influence of the various blast parameters. The empirical model has a modular structure covering all aspects of blast performance including 30 fragmentation, potential rock damage and 30 muckpile profile prediction. The modules are assisted by a terrain model which is compatible to most mine mapping systems, and a blast design editor. The evaluation is summarized in a blast management module. Various studies have recently been undertaken using the model to qualify and improve blast designs with respect to wall stability, optimized fragmentation and muckpile distribution, as well as to the control of the environmental effects such as blast vibration and airblast overpressure. To verify the predictions of the modeling, full scale blast assessment techniques were used to qualify blast geometry, explosives and initiation performance, rock movement, muckpile distribution, near- and far-field vibration levels and airblast ovepressures. The model provides a tool to gain an improved understanding of blasting and blast control. The modeling results are presented in a visual form which allows simple comparisons of proposed blast designs. Additionally, the model can be used for detailed analysis and blast management.

Jan 1, 1996

By William J. Miles

The markets and applications of Wyoming bentonite deposits are primarily determined by the functional properties of a bentonite ore which results from the unique mineralogy and chemistry of each deposit. Commercial bentonite products contain sodium montmorillonite as the major mineral component, with minor concentrations of accessory minerals such as quartz, opal (silica hydrate), mica, feldspar, gypsum and zeolites. The chemical composition of the sodium montmorillonite influences the functional properties of the bentonite in significant ways. The type and concentration of various accessory minerals also influence the acceptability of the bentonite in each market.

Jan 1, 1995

By Luis R. Bittencourt

Research efforts have been made to characterize a refractory Brazilian bauxite ore composed basically of gibbsite, kaolinite and quartz. Detailed polished-section microprobe analysis of the unbroken ore has been used to describe the liberation characteristics and the association between mineral phases. The linear grade distributions for selected particle size fractions were determined by means? of a particular implementation of King's Random Fracture Model that uses the exponential model for the distribution of linear intercepts through both dispersed (kaolinite) and continuous (gibbsite) phases. The corresponding volumetric grade distributions were then determined by means of a constrained optimization technique for the solution of the transformation equation. Batch flotation experiments were carried out to determine the kinetics for particles of different sizes and the results correlated with the liberation spectrum for each size class.

Jan 1, 1991

By Robert J. Garino

Around two-thirds of world silver mine production comes from mines where the majority of ex-mill revenue is obtained from other metals. In this talk I will illustrate the importance of this output of silver as a by-product of the mining of various base metals. I will also consider the impact of relative changes in base and precious metal prices on mill-head revenue, and therefore, on production decisions. During the latter half of 1982 improving silver prices encouraged re-openings at several base metal mines. Thus some production of lead, zinc and copper can be regarded as partly conditional on the prevailing silver price. Conversely, a good deal of silver production can be considered to be independent of the silver price and dependent on the production of some base metal. It is the degree to which the value of silver mined affects the revenues of nominally, base metal, producers that is the central concern of this presentation.

Jan 1, 1983

By Crone Duncan

The search. for massive sulphide orebodies is steadily being extended to greater depths as well as expanding outward into the large portion of the earth's surface where the sulphide bodies are deeply weathered. Massive sulphide orebodies are generally not large in dimensions. They are not like disseminated type sulphide bodies that form large ground exploration targets that can be detected at greater and greater depths simply by increasing the geometrical spacing between the geophysical transmitter and receiver. In¬creasing the transmitter-receiver spacing with massive sulphide bodies eventually "waters down" the anomaly from the body until it disappears into noise. If high surface conductivity is present, as is common in areas of deep weathering, the problem is compounded by the increasing response of the surface layer, as the receiver-transmitter spacing is expanded. The search to greater depths has important implications other than just detection of the orebody. Drilling costs are increased and the probability of missing the target are increased. Missing an orebody is an expense that is difficult to evaluate in dollars per line mile of survey especially since one does not know the value of what was missed. A ground Pulse EM method has the capabilities of solving the problems of deeper exploration particularly in areas of surface weathering it can attain deep penetration without large coil spacings, it also provides information from a complete range of frequencies. The method has other operational advantages since it is free of geometrical restrictions as to coil alignments and can operate in areas of high power line noise.

Jan 1, 1975

By N. Weidner, V. A. Samaranayake, K. Awuah-Offei, S. Que

"This research sought to facilitate improved stakeholder (community) analysis using discrete choice theory (DCT). The work considered 16 project attributes and four demographic factors. The discrete choice experiment was conducted in Salt Lake City, Utah to illustrate the usefulness of DCT in mining stakeholder analysis. The data was used in discrete choice modeling of individual preferences. The approach answers three important questions for enhanced stakeholder analysis: (1) What are the factors that affect individual preferences? (2) What is the effect of demographics on individual preferences? (3) What is the value of environmental and social impacts to individuals in the community? INTRODUCTION Stakeholder analysis is crucial for effective stakeholder engagement because it is important to identify and characterize stakeholders in order to effectively engage in dialogue with them. This is not only true for all stakeholders but true for characterizing the members of a particular stakeholder. The local community is usually the largest and most diverse single stakeholder group. Also, the local community is perhaps the most important stakeholder group. Thus, analysis of the local community is essential for project management. Conventional mining stakeholder analysis is a three-step process, which involves evaluating: (1) each stakeholder’s view of the project (positive, neutral, or negative); (2) how influential each stakeholder is (high, medium, or low); and (3) how they will be impacted by the project (high, medium, or low) (ICMM, 2012). The results of this evaluation are documented in a stakeholder analysis matrix (Table 1), which is used to classify the stakeholders into three groups: highly influential supporter of the project, neutral about the project, and highly influential opponent of the project. This process can be used to describe groups of stakeholders (e.g. community, non-governmental organizations, etc.) or individuals making up a particular stakeholder group (e.g. members of the local community)."

Jan 1, 2016

By Frank E. Chase

Retreat mining is one of the most hazardous operations conducted underground. One of the keys to miner safety and an efficient recovery of the reserves is to design adequately sized production pillars to prevent pillar squeezes, excessive pillar spalling, severe floor heave, roof falls, and pillar bumps. Currently, few pillar design approaches are available which consider the abutment pressures generated by the gob. The Bureau of Mines is developing a method called Analysis of Retreat Mining Pillar Stability (ARMPS) to aid in the design of retreating sections. Back analysis of 42 case studies indicates that ARMPS can be helpful in predicting stability during retreat mining operations.

Jan 1, 1993

By C. Ek

Tailings originating from the gravity concentration of a gold ore containing about 14 g/t Au have been treated by various beneficiation methods. These tailings have been screened on the 147 and 74 micron sieves and the two coarsest fractions have been separated on shaking tables with unsatisfactory results, but the concentrates have been examined in polished sections for mineragraphic analysis. Very simple flotation flowsheets have been applied to collect most of the gold, recovery and grade varying with the regrinding time in a ball mill. Cyanidation tests have shown that this type of treatment is also applicable to such tailings.

Jan 1, 1991

By J. W. Meckenstock

Evidence of the fact that the beneficiation of sand and gravel is now going on is readily observed by visiting various and and gravel plants almost throughout the U.S.A. of necessity this beneficiation process is concentrated more in certain areas than in others, and it is steadily increasing. Therefore, it can be said that beneficiation is now one of the processes inn the manufacturing of sand and gravel, It started some ten to twelve, years ago when the need for beneficiation made itself known, and when the manufacturers of sand and gravel producing machinery began to make equipment available to the industry.

Jan 1, 1958