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By E. L. Gillenwater

Coal mine planning has three distinct decision levels: (1) decisions made at the upper level of management that determine production requirements for specific mines, (2) decisions made at the middle management level, the mine level, that determine how the mine satisfies its production requirements, and (3) decisions made at the operating level of management, the sectional level, that determine the sequencing of machine movements at the face. In this paper, the underground production scheduling problem is formulated in multi-stages using the Hierarchical Production Planning (HPP) approach. Two linear programming HPP models for accomplishing decisions at the first two levels are developed. Both models address the aggregate production planning process. The Mine Production Scheduling (MPS) model permits determination of monthly production and inventory levels. The Section Production Scheduling (SPS) model incorporates a quality blending requirement into the determination of weekly sectional production and inventory levels.

Jan 1, 1995

By Roger M. Buckeridge, Charles D. Reese, Silvio M. Martino, William T. Carey, Ansel H. Graham

FUNCTIONS OF RAIL HAULAGE SYSTEMS The principal application of rail haulage in under¬ground mining is in the movement of ore or coal pro¬duction from near the mining areas out to a processing plant. In some cases, such production haulage may end at a shaft pocket or slope belt conveyor transfer station, depending on the type of mine and the geo¬logical placement of the mineral being mined. Main-Line Haulage The basic reasons for choosing main-line rail haul¬age are high-tonnage production per shift and long haulage distances. The choice between rail and other systems, such as belt conveyors, is not easy and requires an integrated study of many factors: tonnage, distance, grade, product size, number of producing areas, ore reserve, safety, capital cost, operational and maintenance cost, and the mining system. Projecting a main-line rail haulage system for com¬parison with other systems requires a choice of many variables which are interrelated. The project must start with consideration of the mining system, tonnages per day, distances and grades, and loading and dumping conditions. Rail mine cars of different sizes and types are studied. High tonnage demands consideration of wider track gages. A suggested minimum for metal mines is 914.4 mm (36 in.); for coal mines, 1066.8 mm (42 in.). The choice of the train size should be governed by tonnage per shift, physical factors of loading and dumping, cycle time, and the number of trains that can be operated and safely controlled. After the size of the train is determined, the type, size, and specifi¬cations of the locomotive can be selected. The loco¬motive may be trolley, battery, or diesel; selection guides are discussed elsewhere in this chapter. The advantages of rail main-line haulage are high tonnage capacity, flexibility, reliability, safety, low operational and maintenance cost, and dual usage of the system (supply haulage, for example). The dis¬advantages are high capital investment, high installation cost, the requirement for more maintenance facilities, and restriction to certain ore reserves and mine pro¬jections. Supply Haulage Supply haulage is a basic requirement of any mine, but the type and volume of supplies vary with the type of mineral being mined, the mining methods, and the size of the mine. A mine developed for rail main¬line haulage gains supply haulage through the addition of a secondary track system to extend the main line closer to the producing areas. Additional haulage equipment, generally smaller, is also added. It is neces¬sary to design into the rail system more switch bypass points and train control systems. The track system standards demanded by rail main-line haulage con¬tribute to the reliability and efficiency of the supply haulage function, whereas a supply track system to supplement other haulage systems often suffers from poorer track and installation standards. When belt conveyors are chosen for production haulage, a rail supply haulage system is often installed rather than using rubber-tired vehicles for supply haul¬age. The conditions of the seam or ore body create these items for consideration: haulage grade of more than 6% favors rubber-tired vehicles; longer haulage distances favor rail; difficulty in maintaining a smooth roadway favors rail; and movement beyond the end of a rail system generally requires rubber-tired vehicles, making a single system rather than a dual system attractive. Although operation of a supply haulage system may be concentrated on a single shift of a multiple-shift mining operation, proper planning and supervision are required if the haulage is to be efficient. Often the newer personnel at a mine are assigned to supply haul¬age which may add to the difficulty of obtaining maxi¬mum efficiency. Supply haulage by rail offers the advantages of high reliability, lower maintenance, and high efficiency over long distances. The disadvantages are less flexibility, high installation costs, and rubber-tired vehicles for use beyond the inby end of track often required. Personnel Movement The efficient and comfortable movement of the miner to and from his work area has a significant effect on his daily output. Minimizing man-trip time also becomes more and more important as hourly wages increase. Personnel are generally moved over a rail system by one of three methods: a specialized personnel carrier to which a certain number of men who work in a certain area are assigned; a combination vehicle, used to carry personnel but also capable of being used as a light supply/utility locomotive during a working shift; and man-trip cars towed by a supply locomotive. The first and second methods are used in coal mines where long distances make speed and comfort important. The third method is more common in metal mines. Equipment Movement As mining equipment technology has advanced, many mining machines and their subcomponents have grown in size. This trend requires careful planning for adding specialized carriers to handle the movement of larger equipment. Continuous miners, longwall equipment, raise borers, and ventilation equipment are examples of machines which may be difficult to move and which require special handling. The selection of the weight, speed, and operating characteristics of supply locomotives used to move equipment is important. Larger mines may often justify a special group of loco¬motives for this application.

Jan 1, 1982

By Nathaniel Arbiter

A fully-instrumented driving mechanism has been constructed to study the power, aerating and solid suspension characteristics of several laboratory flotation machines. Machines operating over normal flotation speed ranges give constant power numbers in liquid' systems indicating that they operate under fully baffled turbulent flow conditions. Owing to lack of geometrical scaling, power numbers for different sizes of cells of the same make are different. Even larger differences occur between cells of different manufactures. For a given impeller, varying the tank size did not significantly affect the power consumption. Tank geometry and baffling has a slight effect on power consumption with shrouded impellers. For a given impeller speed, suspension height decreases while power increases with increasing mass of solids in suspension. While power consumption is hardly affected by particle size and clearance between the impeller and tank bottom, the suspension height significantly increases as clearance increases and as particle size decreases. Aeration was found to affect not only power but also the suspension characteristics of the machine. For closely sized particles drastic sedimentation occurred when a critical value of the air flow number was exceeded. The critical air flow number decreased with increasing particle size. This effect was less marked with a wide particle size range. The self-aerating capacity of flotation machines increases with cell size at a given speed for the same impeller-shroud system, but decreases in the presence of frother and solids. Equations have been established for correlating all of the studied variables. Data taken from the literature were also correlated with these equations.

Jan 1, 1968

By Sai Phaninder Reddy Chaganti, Corrina D. Beaven

This study investigates the effect of reagent type, dosage, and pH on flotation kinetics and copper recovery for secondary sulfide ore with elevated clay content. The primary objective was to determine whether Xanthate performs comparably to or better than the currently used primary collector, Thiophosphate. Approximately 80 kg of ore was collected from three blast holes and systematically prepared through drying, crushing, grinding, and flotation testing. Grinding tests were conducted to establish optimal grinding time and lime consumption for pH control, achieving a target particle size distribution in 13 minutes and 30 seconds. Elemental and mineralogical analyses using X-ray Fluorescence (XRF) and X-ray Diffraction (XRD) identified a copper content of 0.36% and significant clay presence, affecting flotation performance. Fifteen flotation tests were performed under controlled conditions, with variations in reagent dosages. Control tests confirmed reproducibility, with recoveries around 80–82%. Increasing the pH did not improve kinetics or recovery, making higher pH adjustments economically unjustifiable. Adjusting the Thiophosphate dosage yielded the best recovery of 83%. Xanthate collectors, tested both as tertiary additives and as replacements for Thiophosphate, delivered comparable or superior recoveries—up to 91.5% in plant tests—and demonstrated faster flotation kinetics, even under high-clay conditions. These findings highlight Xanthate’s reduced sensitivity to clay, potential for lower dosage requirements, and operational benefits such as improved selectivity and circuit efficiency, validating its role as a cost-effective and alternative for processing complex sulfide ores.

Feb 22, 2026

By A. C. Barlow

The use of deep wells for waste disposal is not a new technique. The production phase of the oil industry has been using this method to dispose of unwanted oil field brine since the 1930's The adoption of this method by other branches of industry, however, to dispose of manufactured wastes is a relatively new development, but one which is finding increased use (2). Deep well waste disposal is not an ordinary technique even though it is finding relatively wide application. In fact, just the opposite is true; it is still a rather extraordinary measure. It is not now, nor is it ever likely to be a disposal method which can be assured of success before it is tried.

Jan 1, 1964

By D. S. Bubar

This presentation will represent a diversion from the central theme of Cordilleran geology, in both time and space, as we move 2,000 miles east of Spokane to eastern Canada, specifically the province of Quebec, to discuss a major new Archean-age volcanogenic massive sulphide deposit called Louvicourt. The deposit is located in the Val d'Or camp in the prolific Abitibi Greenstone Belt some 400 miles north of Montreal. It was discovered by Aur Resources in June, 1989 on a property operated under the terms of a joint venture with Louvem Mining, a Quebec company controlled by Ste. Genevieve Resources Inc. of Montreal. As a geologist, I am proud to be able to describe Louvicourt as a geological discovery, as it was found by doing systematic deep diamond drilling based on a geological concept. The deposit is essentially blind from surface and lay undiscovered for the 10 years that the Louvem mine was in production just 2,000 feet away from its easternmost workings.

Jan 1, 1991

By M. Javier

Management is a major part of sustainability research. Many different aspects of sustainability have already received significant research attention, but the management processes in mining from the perspective of their impact on society are less understood and integrated as a holistic frame. It is evident that mining technology has received major blame in past ecological disasters and major mining-induced environmental hazards, but the management-mining process has escaped unscathed. This should not have happened. Instead, the management processes should share equal blame with obsolete technology for the failure to identify and monitor potential environmental hazards before their inception of mining. We will present an emergent style of management for the future of mining. It challenges the actual ?mind-set? of mining management. It describes balance and equilibrium: physical, chemical, and biological in nature as an understanding of nature?s language, which is Geomimic along side ?the bottom line?. The goal is to minimize loss instead of maximize profits (waste design) at the design stage of mining and to develop clean technologies (nature's values) to achieve non-social environmental impacts that provide a prosperous legacy to future generations.

Jan 1, 2010

By J. R. Batista, J. C. Young

Leachates from gold heap-leaching mines may contain selenium concentrations as high as 2 mg/L. Previous studies report satisfactory selenium adsorption by activated alumina from relatively "clean" drinking waters. However, the findings of these studies cannot be directly applied to the treatment of mine leachate where other ions compete for the alumina adsorption sites. This study evaluated the adsorption of selenium from a mine leachate to develop design parameters for a full-scale activated alumina process. The study revealed that 68% of the selenium in the leachate could be removed by alumina at pH levels greater than 5.0. At pH levels less than 4, silica was poorly adsorbed by alumina, and selenium adsorption was improved. Silica adversely affected the selenium adsorption capacity.

Jan 1, 1998

By Ray E. Williamson

One of the prime objectives of the mine industry is to develop a low cost way to clean up what has been called "The Rape Of Mother Nature". The project falls under the broad umbrella of reclamation, which is now considered an essential part of the mining cycle. As such, it is being given full consideration in the initial planning of all surface operations. In most areas, if a proposed mining system does not lend itself to proper reclamation, it is not an acceptable system. By combining mining and reclamation plans, a producer not only can minimize reclamation costs, but can also restore the land to usefulness and insure continuing profits after a deposit is depleted. As long as fifteen years ago, many of the larger mining companies were already deeply involved in this extra cost work. Even then the involved companies were projecting a great need for a bigger bulldozer, Bigger than anything commercially available. At that time, the D9 tractor weighed about 60,000# bare weight.

Jan 1, 1975

The General Purpose Simulation System (GPSS) is a computer simulation language that has been used for simulations of open pit haulage operations since the 60's. It is easy to learn, simple to use, and has a block-diagram structure that is amenable to load-haul systems. However, due to its lack of flexibility, there are situations where another language should be chosen. This paper reviews the characteristics and capabilities of both GPSS and FORTFAN with regard to open pit shovel and truck simulation. The relative advantages and disadvantages are highlighted and a case study presented along with comparative results from two computer models (one written in GPSS and the other written in FORTRAN).

Jan 1, 1986

By A. B. Van Cleave

It was first pointed out in 1934 by Gaudin (1) that the "oily" oxidation product of the alkyl xanthate ion-dialkyl dixanthogen, might be the "active flotation agent" on sulphide minerals and there have been a number of studies supporting this hypothesis (2,3,4). However, all of these studies have relied largely on electrochemical evidence. Galena, being a semiconductor, may be used as an electrode in aqueous solution and it was shown that ethyl xanthate ion does not adsorb with charge transfer in the absence of oxygen unless the potential of the galena surface is above -100 mv versus the hydrogen electrode (H2 E). At this potential the galena surface is slightly hydrophobic but does not become strongly hydrophobic unless the potential is raised to 210 mv (versus H2 E). It is suggested that, at potentials of 210 mv or above, ethyl xanthate ions are oxidised to diethyl dixanthogen and that chemisorption of oxygen raises the galena surface to this potential. On the other hand, examination of xanthated galena surfaces by chemical or physical methods (5,6,7) has failed to detect dixanthogen and it has been shown that dixanthogen may be reduced to lead xanthate at a lead sulphide surface. (5,8)*. It was suggested by Leja and Poling (5) that, as dixanthogen is a neutral molecule it would not be repelled by the negatively charged galena surface so that the adsorption was envisaged as taking place through homogeneous oxidation of the xanthate ion to dixanthogen, adsorption and reduction of the dixanthogen to a chemisorbed lead xanthate species. In paper I of this series (11) it was shown that the thiosulphate ion, which forms on galena surfaces in slurries at the pH normally used for flotation, will reduce dixanthogen. There is, therefore, the impasse that the electrochemical evidence requires that xanthate ion be oxidised to dixanthogen at the galena surface while the chemical evidence shows that the reverse reaction takes place.

Jan 1, 1973

By O. Ditsele

Coal plays an important role in the energy needs of the World. Given its wide abundance and low cost, coal use is bound to increase with the growing energy demand. Despite its importance, there are growing concerns over coal?s environmental burdens, especially its contribution to greenhouse gas emissions. To ensure sustainable extraction and use of coal, opportunities for minimizing potential impacts from coal have to be identified and exploited. Whilst extensive work has been done on life cycle assessment of coal use, especially in electricity generation which uses the bulk of coal produced, there has been limited work focusing specifically on coal mining. This study aims to estimate the cradle-to-gate life cycle climate change impacts of coal from a surface coal mine in the United States. The study employs general principles of ISO standards for LCA.

Jan 1, 2010

By C. Hanson

Two modes of potential loss of oxime extractants in liquid extraction processes for the extraction of copper have been studied. In loss "by chemical degradation, two mechanisms of acid hydrolysis are possible, some reagents degrade primarily in the organic bulk phase, Others at the interface between the organic phase-- phase protects the oxime but salts added to the aqueous acid phase can promote the rate of degradation. The reagents reported on are the LIX series (Henkel Cpn), SME529 (Shell Chem.Co.) and P5100 (Acorga) Loss by organic entrainment in the aqueous phase leaving mixer-settlers has also been studied, parameters investigated including impeller/tank geometry and the phase inlet arrangements. The consequences of extractant loss by the above mechanisms...are commented upon. They include the direct economic cost, the possible environmental problems and the implications for downstream operations such, as electrowinning.

Jan 1, 1980

By A. T. Stroebel

Diatomite deposits, the skeletal remains of tiny aquatic plants called diatoms, are found in many parts of the world. Only a few of these de- posits are of commercial value. Open pit mining is used in nearly all deposits now being worked. Processing methods range from simple drying, crushing, sizing and packaging to carefully controlled and highly sophisticated calcining and air classification procedures, employing the latest control and testing techniques. The major uses of processed diatomite are in filtration as filter aids and fillers and extenders.

Jan 1, 1979

By I. Iwasaki

A low-grade copper-nickel deposit, with an estimated size of 4.6 billion tonnes and with average analyses of 0.6% copper, 0.2% nickel, occurs in northeastern Minnesota. In addition to copper, nickel, cobalt, and precious metals, the Duluth gabbro contains magnetite, ilmenite, olivine, plagioclase and biotite. It is estimated that the flotation tailings that would be produced by a concentrator of optimal size to sustain a smelter would amount to 20 million t per year. The flotation tailings, having already been ground, warrant a closer examination for the recovery and utilization of potential by-products. The residual sulfide minerals and fibrous minerals may also be isolated and treated separately for useful purposes or for disposal in an environmentally acceptable manner. Two flowsheets were developed; one involving preconcentration by low- and high-intensity magnetic separation and another involving preconcentration by gravity concentration. The concentration methods for recovering and purifying individual by-product minerals were investigated. From their chemical, physical and mineralogical characteristics, the potential areas of application and marketabilities of each product fraction were surveyed.

Jan 1, 1983

By E. L. Piper

Natural graphite has been known for many centuries, having first been reported as a distinct mineral form by Gessner in 1565. At that time, graphite was used extensively as pencil "lead" because of the ease with which it marks paper. It is a black, unctuous material found as flakes, lumps, or needles in scattered locations throughout the world. The less crystalline, or "amorphous", natural graphites are thought to have been formed from coal under conditions of high temperature and pressure. The more crystalline varieties, such as those mined in Ceylon, probably were precipitated from molten solutions or were pyrolyzed from gaseous carbon compounds. Recognition of the good thermal and electrical conductivity of graphite, together with its highly refractory nature, led to an increasing number of appli¬cations for this material. Clay and pitch bonded natural graphite has been used in crucibles, refractories, foundry facings, and other high-temperature appli¬cations. These forms constitute the most important current uses for natural graphite in the United States. Other products containing natural graphite include batteries, lubricants, pencils, brake linings, etc.

Jan 1, 1973

By K. L. Ludeke

For many reasons it appears that deep-rooted, perennial shrubs offer potential for improved stabilization and provide maintenance-free vegetative cover to harsh sites where perennial grasses have not been successful. The very fact that a drought-adapted shrub has a massive root system that can use moisture from a greater volume of mineral waste soil materials suggests that long-range arid environment resource development may be greatly enhanced by utilization of desirable forage shrubs. An effort is underway to assemble information and plant materials of promising species from many arid regions of the world. Surprisingly, many of the better plants for arid sites are quite high in protein content, and with proper management, breeding, and selection may prove to be very desirable livestock feed. Advancements in arid-land solid waste stabilization hold favorable promise for many industries that mine and mill in arid regions for effective reclamation of disturbed areas. Particularly exciting is the possibility of establishment of high density maintenance-free vegetative cover of climax vegetation that reclaims the disturbed area back to its original land use. Because of high shrub productivity, stabilization potential, nutritional quality, and reclamation success, greater use should be made of shrubs in disturbed land reclamation associated with mining and milling operations in harsh arid environments.

Jan 1, 1984

By L. J. Altenburg

There are a lot of key factors involved in achieving a successful Safety Program. I would like to discuss some of these factors and how they have played a major part in our success at Jacobs Ranch Mine. The areas I will cover concern: 1) Facility Standards (Corporate/Minesite), 2) Communication (Employee/Management -"Teamwork"). 3) Proper Training (Employee/Management). 4) Employee Attitude. 5) Incentive Programs. 6) Health Programs. 7) Results/Benefits.

Jan 1, 1994

By Robert J. Wright

The purpose of this paper is to propose a classification of uranium deposits that is believed to be well suited to the needs of uranium exploration and resource assessment. By way of background some observations are offered about mineral exploration in general, and uranium in particular. Attention is first given to the we of models in mineral exploration. Some general principles of mineral deposit classification, the basis for model formulation, are then considered. Finally, the uranium classification is presented.

Jan 1, 1979

By J. N. Cox

Coal preparation is based on the properties of noncombustable materials (impurities) in coal being different from the organic constituents. The most commonly used property difference is density, via its affect on settling rates; and either gravitational or centrifugal forces can be used to remove impurities. However, examination of various particles settling rate correlations shows that at smaller sizes, particle drag becomes a very important factor. Classification, based on differential settling rates, becomes impractical and some property other than density must provide the basis for fine coal cleaning. Froth flotation and agglomeration employ differences in surface properties to clean coal. These methods are very successful except that the oxidized surface of a pyrite particle is somewhat hydrophobic and will tend to be collected with the organic portion of the coal. Surface property cleaning techniques have not been very effective in rejecting sulfur, except for two-stage flotation.

Jan 1, 1984