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By C. Stacy

The mining industry is changing rapidly. Competition among OEM and aftermarket vendors increases dramatically each year as a result of mergers and acquisitions, and especially technology advancements in the mining industry. Adding value to mine operations by delivering technical value and differentiation is becoming more subtle and more difficult to accomplish. Because of this, identifying and protecting intellectual property has become more important to the product development, engineering and marketing/sales continuum than it had been in the past. How companies protect intellectual property and determine the value of those assets is critical to the sustainability and differentiation of technology providers in the mining industry.

Jan 1, 2012

By R. Bruce Tippin

because of the mineral's high monetary value and the spotty occurrence of free gold in the deposit. Setting up a plant sampling procedure by simply applying the usual statistical sampling theory was questionable. Two sampling concepts were considered in the sampling study: o a sufficient number of assays can be taken such that the average determined from these individual samples represents a known quantity of ore. o a sufficient weight of sample can be taken such that when assayed it represents a known quantity of ore. The test program included evaluation of sampling techniques, sample preparation and analytical methods. The overall sampling program is depicted in Figure 2.

Jan 1, 1985

By R. Kramer, A. Habibi

A ventilation survey was conducted in an underground longwall trona mine. The mine is relatively shallow and categorized as a gassy mine. The ventilation system includes three intake and six exhaust shafts, and three surface axial fans ventilate the mine in a blowing configuration. Airflow quantity, pressure losses and air psychrometric characteristics were quantified, and the influence of moving cages and skips in the shaft examined. The benefits of utilizing high-accuracy digital pressure transducers and advanced psychrometers were seen when undertaking a “leapfrogging” survey to gather data needed to build a computer ventilation model. Two underground booster fans with VFDs are idle but available at the mine. The ventilation model was used to determine the optimal booster fan locations to decrease operating cost by reducing the load carried by the main fans. A leakage study was conducted to evaluate the effects on the system of additional pressure from a booster fan. The study finally prepares a future ventilation model for the next 15 years of mine operation and investigates the effect of proposed scenarios.

Jan 1, 2014

By J. H. Daniel

The reduction of accidents will play an ever increasing role in the mining of coal and hardrock ores as mining operations become more mechanized, the equipment becomes more costly and sophisticated, and as mineral production exploits deeper and more marginal coal and ore deposits. The most effective means to reduce accidents is through the design of mining systems and equipment. Results of safety research by the U.S. Department of the Interior, Bureau of Mines, to design safer coal extraction and haulage systems and to reduce electrical accidents are presented.

Jan 1, 1991

By L. Adler

The valuable Maximum Utilization Factor (MUF) concept has been extended to other rotating excavators beyond stripping shovels and draglines. In this concept the boom reach and bucket capacity are multiplied to get an MUF, then normalized by dividing by the equipment weight. Statistical analyses were applied to the remaining shovels (hydraulic and cable), draglines, and backhoes. Positive correlations were found. Stripping shovels and draglines were also re-examined. The results provide an estimate of equipment diggability and encourage versatility by the interchange of the boom and the bucket. The concept further clarifies the existing equipment classification by delineating general excavating, loading, and stripping kinds. The results also forecast trends, and noted innovative advances and possible retrogression. Extension to other boom excavators, such as front-end loaders is recommended. The MUF concept provides one of the few indices of gross external characteristics available to the engineer-user of equipment.

Jan 1, 1990

By A. Martikainen, H. Dougherty

"At the Kemi Mine, a recent expansion into the Surmaoja orebody required an increase in ventilation capacity. A new ventilation shaft was built with two main fans. The installation is near the entrance gate and only 1.7 kilometres from the nearest permanent dwelling. The main fans were first taken into use as exhaust fans in October 2014. Shortly after the fan installation, comments concerning fan noise were received from the neighbours. The first noise measurements were taken at the main fan installation site by Outokumpu personnel in March 2015. Due to higher than expected recorded values, during late June, 2015, a two-week environmental noise study was planned by the engineers and executed by a consultant specialized in noise measurement. The measurement results were analysed and compared to the requirements of the environmental permit and Outokumpu’s factory standards. While the measured values at the nearest dwelling were within the environmental permit limits, high noise values were recorded at the fan station. A second two-week study will be performed after construction of the main-fan heating station has been completed. Actions taken will depend on the outcome. INTRODUCTION The Kemi Mine is a part of the Outokumpu chain of integrated ferrochrome and stainless steel manufacturing in the Kemi-Tornio region in Finland. The mine itself is a large underground operation with a production capacity of 2.7 million tons of ore per annum. It is also the European Union’s only chrome mine, and at present (2015) the mine extracts 2.4 million tons of chrome ore per year. Safety, cost-effectiveness, and environmental friendliness are hallmarks of the Kemi Mine. Environmental impact produced by the operation of the mine is limited due to the insolubility of the oxide chromium ore, the gravity-based and chemical-free enriching process as well as the closed circulation system of the process water which serves both the whole mine and the enrichment process (Outokumpu, 2015). Importance of the environmental impact of the Kemi Mine is amplified by its closeness to the cities of Kemi and Keminmaa with the nearest habitants living less than 2 km away from the mine site. To show the cooperation with residents the Kemi mine organizes special “neighbour days” for the habitants of the areas closest to the mine. Also, information letters are sent to the neighbours, when changes that may affect the neighbours are being planned and executed."

Jan 1, 2016

By Neil D. Donnell, O&apos

Bituminous sands of the Lower Cretaceous McMurray Formation in northern Alberta constitute the ore for the surface mining operation at Syncrude Canada Ltd. These sediments represent a complex succession of fluvial, estuarine and marine depositional environments. Grade prediction is realized through a combination of geological interpretation, computer modeling, and reference to past mining experience. Accurate forecasts of feed grade permit reliable predictions of volumes for removal to meet budgeted synthetic crude oil production. This planning facilitates efficient allocation of mining equipment and resources. The feed grade to the Extraction Plant is monitored at various points along the delivery system.

Jan 1, 1984

By John W. Straton

Following the completion of the paper presented in February, 1972, data were received from many other mines and some original respondents submitted more complete questionnaires. The computer program was changed to permit the results to reflect more clearly all the data reported by the mines. The original paper was revised to reflect the new information. There were significant changes in some numerical values, particularly where the size of the sample changed appreciably. Some limited samples considered originally in arriving at conclusions were not relied on in this revision. The revised tables and text are of the same design and format as the original paper.

Jan 1, 1972

By Robert M. Cox

Surface mining of coal in the South developed into a major industry during the 1960's. The economic significance of the industry is much greater than is readily apparent when one considers only the value of the coal mined. The abun-dant supply of relatively inexpensive steam coal for electric power generation that has been derived from the surface mines has provided the foundation for the industrial expansion that has occurred throughout the South. The region, in gen-eral, has enjoyed the benefits of plentiful low cost electric power. However, re-cent political decisions, at all levels of government, threaten to destroy or severely curtail the surface mining of coal and eliminate the economic advantages once enjoyed by the region. These political decisions are rapidly changing the basic rules of operation and fundamental economics of surface coal mining. Recent changes, resulting from the enactment of environmental and health and safety laws and various bureaucratic rules and regulations, have had a three-fold effect: 1) Greatly increased operating cost, 2) increased lead times for mine development, 3) limited potential reserve base for future mining. Also current legislative proposals are casting a shadow of uncertainty over the future of all coal mining operations that has created serious delays and in-creased cost for the expansion of the coal industry necessary to meet our project independence goals. Technology Surface mining is the safest and most economical way to produce raw materials from the earth's crust. It also affords a more healthier working environment for the individual miner. Surface coal mining now accounts for more than 60 percent of the annual coal production in the South. Surface mining of coal requires the removal of the overburden to expose the

Jan 1, 1977

By G. Delagrammatikas, M. Karmis, J. Mastoris

The evaluation of raw materials in terms of quality profile, mineralogical character and mechanical properties is of great importance to the cement industry. The variability of their chemistry and structure is among the decisive design parameters in the choice of any mining, handling and preblending systems. Furthermore, clinker and cement production require sound estimates of the above parameters, to help produce some appropriate and realistic raw mix configurations and achieve minimum standard deviation of the major components. This paper addresses this subject from the perspective of a cement producer and presents the principles of a methodology aimed at optimizing mine planning and process design. Finally, results from case studies on actual sedimentary deposits currently in operation are discussed.

Jan 1, 2002

By Daniel E. Walsh

A pilot scale study was performed to evaluate the potential for gravity concentration of gold from -13 mm (-1/2"), crushed ore from Ester Dome, Alaska. 9.04 tonnes (9.94 tons) of crushed ore were sampled and processed through a Pan-American jig -Wifley table pilot plant. Plant products were sampled for assay and material balance calculations. Gold recovery through one stage of jigging and two stages of tabling was 17.4% at a concentration ratio of 615:1. Concentrate grade was 766.3 g/tonne (22.4 oz/ton). The feed grade to the plant was calculated at 1.71 g/tonne (0.050z/ton). Jig tailings, primary table tailings and secondary table tailings grades were 1.44 g/tonne (0.042), 1.30 g/tonne (0.038), and 5.47 g/tonne (0.16 oz/ton) respectively. Significant, coarse, free milling gold values were shown to remain in the jig tailings. Concentrate mineralogy is discussed.

Jan 1, 1991

By Diogo Peixoto Cordova, Italo Gomes Gonçalves, Andre Cezar Zingano

The top-down extraction sequence in the sublevel open stope method relies on rib pillars to support excavations, making pillar and stope stability crucial for controlling dilution. This study introduces an integrated methodology using a genetic algorithm to optimize the layout of open stopes and rib pillars while considering both economic and geomechanical performance. The methodology incorporates user-defined parameters such as the minimum size of stopes and pillars, maximum accepted dilution and acceptable percentage of pillar failure. A profit function that attributes economic value to the geometric configurations, including geomechanical performance, is employed. The geomechanical performance, assessed using numerical models in FLAC3D, includes the average percentage of pillar failure and potential dilution. The study was tested on a mining panel from an underground gold mine using a top-down mining sequence. The optimization achieved an 8 percent increase in net profit compared to the traditional engineer’s design when 70 percent hangingwall support efficiency was assumed, and a threefold reduction in pillar failure percentage. When no hangingwall support was considered, the net profit increase reached 22 percent. These results demonstrate that the proposed methodology enables integrated optimization, balancing mining costs with geomechanical performance and reducing the need for secondary support compared to traditional methods

Nov 1, 2024

By S. Mendenhall

The Golden Sunlight Mine (GSM) began operation in 1982 with a strong commitment to environmental stewardship and the local community. This commitment ensured the long-term physical, chemical and ecological stability of the mine site and maintained an active partnership with local stakeholders. Concerns for economic development intensified as mine closure loomed on the horizon and fostered the inception of the Community Transition Advisory Committee(CTAC).This coalition of interested area stakeholders has the primary focus to sustain current mining operations while concurrently seeking alternative post-mine economic development opportunities utilizing existing mine assets. Accomplishments include development of an Asset Re-utilization and Post-closure Plan, a community survey regarding the impending mine closure, recruiting an international wind energy company to develop a wind farm, and development of an industrial/business park. The synergy of this strong partnership is key to meeting sustainability goals and enhancing potential future mining operations. The cooperative effort of the GSM and the local stakeholders is a success story that could be a role model for other mining operations.

Jan 1, 2004

By C. L. Lin

A PC image-based on-line coarse particle size analyzer has been developed to measure particle size distributions under plant situations where overlapped particles are being transported on a moving belt conveyor. Although previous testing had shown satisfactory performance of this image-based system for separated particle size measurements (the non-overlapped case), it was necessary to modify original algorithms in order to solve the overlap problem and make the system suitable for plant operations. On-site testing has been conducted at a large copper concentrator in the southwestern U.S. for further investigation of the overlap problem.

Jan 1, 1995

By Carl Rampacek

Laboratory and small-scale continuous pilot-plant investigations made at the Tucson Metallurgy Research Laboratory of the Bureau of Mines have demonstrated that the copper segregation process is applicable to the treatment of oxidized and mixed oxide-sulfide copper ores regardless of the gangue constituents. The process comprises heating the ore to a temperature of 750° C. with small quantities- of sodim chloride and coke to produce metallic copper, which then is recovered by flotation. Tests were made on' 23 copper ores of different types containing 0.8 to 5 percent Cu, .The copper recoveries ranged from 73 to 96 percent in concentrates assaying 10 to 62 percent Cu, depending on the grade and type of ore, The direct operating cost for a 1,000-ton-per-day furnace and flotation plant is estimated at about- $3 per ton of ore.

Jan 1, 1960

By W. Chae

The influence of solution ionic strength (IS) and electrolyte valence on the flotation behavior of malachite has been investigated. The microflotation tests were conducted over a range of solution IS (1?300 mM) at a constant speed (340 rpm), pH (9.5), flotation time (10 min), and sodium oleate dosage (5.3×10-7 moles/g). The size of malachite ranged from 45 to 53 µm, and two different types of electrolytes (NaCl and CaCl2) were employed. Electrophoretic mobility was also measured over the same IS range employed in the microflotation study. Overall, strong coupled effect of solution IS and ion valence was observed. Specifically, the flotability of malachite increased with increasing IS in the presence of monovalent cation (Na+) while the flotability increased up to 30 mM and decreased with increasing IS in the presence of divalent cation (Ca2+). Notably, the flotability of malachite was greater with the presence of Na+ compared with Ca2+ under high IS conditions (IS>30 mM). Consistent trend for Na+ versus Ca2+ was observed from the flotation results with different SO dosages. The characterization and flotation results suggested that the trend was likely attributed to the increased unfavorable interaction between malachite and bubble via the charge reversal of bubbles and malachite at higher IS in the presence of Ca2+.

Feb 27, 2013

By R. S. Olsen

Intensely altered rock has had a large effect on slope stability as slopes increase in height at Island Copper mine. Traditionally used, fracture-controlled rock slope stability design techniques have been supplemented with analyses of failure modes which include failure along curved surfaces typical of soil materials. A rock mass rating (Pa) system has been developed that addresses the lower end of rock mass strengths. Rock masses are rated in terms of fabric integrity, alteration, fracturing intensity and gouge strength. Rock mass classes have been defined using statistical frequency distributions of rock mass rating values. Strength values have been assigned to the various classes from shear testing, back analyses of failures and engineering judgment.

Jan 1, 1987

By S. Upadhyay, A. M. Afrapoli

"Fluctuation in market price of mineral products has enforced mining companies to cut down their operating costs. One useful way of reducing operating costs in mining operations is to make optimal operational decisions, incorporating efficient mining fleet management systems (FMS). Over the last 50 years, several types of FMS have been developed and introduced in the mining systems around the world. However, there are two major shortcomings in existing systems. Firstly, none of the existing systems consider effects of the short-term plan on dynamic truck assignment. Secondly, most of the existing FMSs make decisions in a way that optimize a specific objective while ignoring others. Herein, we propose a multi stage and multi objective FMS that deals with aforementioned shortcomings of the currently available systems. The developed FMS, in its upper stage, links semi-dynamic operational decision making process to the short-term production plan by simultaneously assigning shovels to mining faces and allocating trucks to the shovels by implementing its first multi objective decision making model. Then in its second stage, in a real time dynamic decision making process, it assigns trucks to shovels and corresponding destinations by optimizing its second multi objective decision making model. The developed fleet management system has been verified using an Iron ore case study and the results are presented in this paper. INTRODUCTION Open pit mining method is the most common method to mine mineral from the earth. Based on Wetherelt and van der Wielen (2011) there exist 2500 open pit metal mines that are categorized as industrial scale mines. Over all of those, the amount of material handled using truck and shovel material handling system is more than the amount handled by all other systems together (Humphrey & Wagner, 2011).It has been proven by several studies that more than 50 percent of operating cost in a truck and shovel based open pit mining operation is accounted for material handling (Moradi Afrapoli & Askari-Nasab, 2017, Alarie & Gamache, 2002, Ahangaran et al., 2012). Thus, introducing even 1 to 2 percent cut in its material handling cost saves huge amount of money for the stakeholders. Over the last 50 years, two major areas have been identified to cut this cost. On one hand mining industries have been implementing equipment with higher production capacities, and on the other hand, researchers have been developing operations research techniques to make dynamic decisions as close to optimal as possible to deduct operational costs in truck and shovel based mining operations."

Jan 1, 2018

By M. Yavuz

Due to workability difficulties, people have begun to use iron ore much later than gold, copper and bronze. In addition, iron and steel products are the most commonly used metals which are necessary for human life today. It is a fact that iron ore is raw material of the steel production process as known. Iron&Steel sector is plays an important role in the economic development of countries all over the world. Therefore, the amount of production and consumption of steel is one of the basic indicators of industrialization all over the world. The amount of steel consumed per capita of the country is considered as a measure of development. The world average per capita consumption of steel is around 210 kg in 2007 (Yildiz, 2009).

Jan 1, 2010

By J. L. Thompson

Lime made in a coal-fired, rotary kiln has two distinct parts: the interior of the pebble which constitutes about 90% to 95% of the mass, and the surface dust layer which is the remaining 5% to 10%. Uncalcined carbonate and impurities in the product may be present and will not contribute to the hydration reaction. Sulfur, in the form of calcium sulfate, inhibits the hydration reaction out of all proportion to its actual weigh-percent concentration (perhaps more than 100 times). If the stone contains dolomite, this will also inhibit the reaction as its rate of hydration may be nearly 3 orders of magnitude slower than that of calcium oxide. Early in the hydration reaction dolomite appears practically inert, but given sufficient time, it will hydrate. The heat of reaction is nearly the same as for calcium oxide, but the time necessary for complete hydration may be hours; whereas for calcium oxide it is only fractions of a second. The dust layer on the surface also inhibits hydration as it contains a collection of compounds which have low heats of hydration. This layer can tie up additional calcium and delay or prevent its reaction. In addition to these chemical processes, an important physical characteristic of the lime is its specific surface area. This is effected by the thermodynamics of calcination and the original stone grain chemistry. All of these factors are agglomerated in the gross slaking rate of lime. The total hydration of the chemical complex that is called commercial lime can be more easily understood by considering the individual reactions and combining them to form a more comprehensive picture of the situation. Calcium oxide and magnesium oxide hydrate similarly, differing only in their reaction kinetics. Dolomite, however, reacts differently than a simple mixture of calcium oxide and magnesium oxide as its hydration is strongly influenced by calcination thermo-dynamics and stone grain structure. Finally, the dust hydration and composition should be examined Understanding these reactions enables one to examine hydration reaction graphs with more insight into the factors which determine their shape.

Jan 1, 1978