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By Michael E. Lively

DOUG HALBE: We've talked about copper operations and gold operations. For our third section on the topic "Operating Ideas That Have Saved Me Some Bucks," we'll turn to the coal fields. Our featured speaker is, I'm almost embarrassed to say, a mining engineer, Mike Lively. Mike has 25 years' experience in the coal industry. He is currently superintendent of surface operations for Southern Ohio Coal Company, Meigs Division (AEP Company). I've read his paper, and there's some really great information here. Mike.

Jan 1, 1998

By E. H. Partelpoeg, B. G. Belew

In 1990, the Chino Smelter completed the construction of a plant designed to recover metal values and water from smelter scrubber effluent. Equipment was installed to maximize effluent recycling and minimize costs. The process utilizes magnesium hydroxide as a neutralizing agent which has the advantage of precipitating copper from solution with minimum generation of solid reaction products. The neutralized stream is clarified, with solids recycled to the smelter for metal recovery while the clarified effluent is recycled to the concentrator for use as process water.

Jan 1, 1992

By Hayward B. Oblad, Gary F. Meenan

Two optoelectronic detectors were developed by CONSOL R&D for fine coal processing applications. One sensing device is used to estimate the amount of fine coal in the solids fraction of the froth flotation tailings slurry. The other probe, based on similar technology, is capable of measuring sol ids concentrations as high as 10 weight percent in fine coal slurry streams. These patented optoelectronic sensors are installed in several CONSOL coal preparation plants and are an integral part of the fine-coal control systems.

Jan 1, 1993

By L. F. Barrett, D. E. Cameron, J. C. Wilson

Exploration by Anaconda Minerals Co. in the Rico area from 1978 through 1983 resulted in dis¬covery of the Silver Creek molybdenum deposit. The drill-indicated resource is 40 Mt (44 million st) of 0.31% Mo, and projections suggest that the deposit may exceed 182 Mt (200 million st). No source intrusion has been intersected by drilling, but its presence is sugested by intramineral silicic alkali-alaskite porphyry dikes observed at the surface and in drill holes. Age dates and fluid inclusion studies indicate that the deposit was formed 5.2 ± 0.2 m.y. ago and that more than 1200 (3937 ft) of cover has since been removed by erosion. The deposit is hosted by Precambrian quartzite and greenstone, and Paleozoic sediments. Three prominent faults intersect in the vicinity of the molybdenum deposit, and one of these, the Last Chance fault, strongly influenced the shape and location of the deposit. The juxtaposition of host rocks across the Last Chance fault reflects significant offset spanning at least three different periods. Wallrock alteration associated with the deposit includes potassic, phyllic, and propylitic zones in noncalcareous rocks and garnet and anhydrite-diopside zones in the carbonates. All +0.2% Mo mineralization is within the potassic and garnet zones. Premineral faults that intersect the deposit contain the only surface molybdenum, tungsten, and fluorine anomalies. Dispersion halos of the indicator elements were defined by drilling in the discovery phase of exploration, and are particularly well-developed in the hanging wall of the Last Chance fault.

Jan 1, 1987

By Mark A. Anderson

INTRODUCTION The accomplishment of a well engineered design, and the realization of efficient plant operation cannot be achieved without weaving a web of safety consciousness from the beginning of the project. When the plant becomes operational, and throughout its life, responsibility safety will rest with the client or operator. Recognition of this understanding does not reduce the importance of the engineering and construction contractor's role, but merely puts the responsibility where it belongs. A project which has had little or no operator input during the early stages of design is almost certain to have serious work place safety, health, and environmental problems in spite of the fact that all MSHA and OSHA design requirements were met and the engineering was performed using accepted practices. DEFINITIONS The author has a personal preference in safety definitions that begins and ends with simplicity. If the safety criteria, program, and rules are confusing or complex, the results will soon become obvious. Confusing and complex are the key elements in the avoidance of responsibility and if punitive is added to the list, a brew exists which breeds accidents, illness, and poor performance. A safely designed and operated plant is one that a worker can journey to each day; leaving that person and his or her family with the above average expectation that the person will return healthy, emotionally intact, and hopefully a little wealthier. If the objective or results of a planned or existing safety program don't fit the definition. then the reader is probably contemplating a very sophisticated

Jan 1, 1986

By T. R. Ellis

Considerable movement is afoot internationally to rationalize standards and regulations relating to valuations and the qualifications for valuation professionals. In July 2000 the International Valuation Standards Committee released expanded standards, and additional important improvements are planned by 2003. Possible updates to the International Accounting Standards (IAS) and potential adoption of IAS by the United States could significantly impact minerals appraisers. Standards designed specifically for mineral asset valuation are under development in Canada and the United States, with Australia's internationally respected VALMIN Code providing the benchmark. In the United States, the all-encompassing Uniform Standards of Professional Appraisal Practice (USPAP) is annually modified and continues to gain deeper acceptance, while the SEC holds fast to its 1981 rule prohibiting reporting of a quantitative estimate and value for non-reserve mineralization. Some important international trade agreements are driving actions to free the trade in professional services. In July 2000, an international workshop was held to initiate discussion on minimum qualifications for appraisers to work internationally. Pressure for uniform minimum qualifications and rules for professionals internationally will continue to build. The United States is historically among the slowest countries to implement such initiatives, with its state level licensure barriers having the potential to cause some of its professionals to be stranded in an international backwater. Structural change is needed in Australia's VALMIN Code to remove conflict with the latest International Valuation Standards. The mineral valuation standards developers of Australia, Canada and the United States should work jointly on updating VALMIN for global use.

Jan 1, 2003

By John M. Anderson

This paper examines the methods available to improve climatic conditions around a deep, high production longwall district of a British coal mine using results from a computer model. Such methods include the provision of increased ventilation quantities, the application of refrigeration, the reduction of heat input at source and the use of alternative ventilation systems. An approach to the solution of a climatic problem is explained with reference to other coal mine contaminants and a cooling strategy for deep high production British coal mines is described.

Jan 1, 1987

By Steve Kral

Philip M. Hocker is president of the Mineral Policy Center (MPC), a Washington, DC-based, non-profit organization formed to "address the environmental problems that are caused by mineral development in both the hard-rock mining and onshore oil arenas." Hocker has been involved with resource development and environmental policy issues since the 1970s. He has been a plaintiff in several lawsuits regarding environmental management of federal onshore oil and gas leasing. He was also active in the 1987 campaign to pass the Federal Onshore Oil and Gas Leasing Reform Act. Hocker served on the board of directors of the Sierra Club from 1980 through 1986. He is also a member of SME and spoke at the welcoming luncheon and keynote session of the SME Annual Meeting and Exhibit, Feb. 14, 1994, in Albuquerque, NM. In his role as president of MPC, Hocker has become a major player in the ongoing battle concerning mining law reform. And, while the mining law issue is the most visible and controversial issue confronting the mining industry and MPC, Hocker's organization is also active in clean water reform and other public policy issues that concern natural resource development and the environment. Hocker and MPC invoke a wide spectrum of reactions from the mining industry, most of it negative. Even so, the editors of ME decided that SME members should hear from Hocker his views on domestic mining, including mining law reform, clean water legislation and other environmental issues facing the industry.

Jan 1, 1995

By Thomas E. Krakowski

INTRODUCTION This paper presents a method of calculation of internal moments and thrusts in tunnel liners of any material. The method is intended for hand calculation, but as it is numerical in nature it can be programmed for use in computers. The information required for design or analysis is presumed active internal and external pressures, the effective moment of inertia and cross-sectional area of the tunnel liner, the liner's modulus of elasticity, and the coefficient of subgrade reaction of the material surrounding the tunnel. Starting with active external and internal pressures and following the procedure described herein using the structural properties of the liner and surrounding medium, external passive reactions and internal moments and thrusts are calculated. The method is intended for use by design engineers. GENERAL Experience has shown that flexible tunnel liners have less internal bending stresses than those calculated using classical structural theory applied to free-standing arches. In fact, liners which are very flexible in relation to the surrounding soil or rock have virtually no bending moments when compared to free-standing arches supporting equal active loads. In order for this phenomenon to occur, the original active pressure diagram must be "modified" by additional external reactions (passive pressures) from the surrounding material, so that the thrust line within the lining follows the centroid of the tunnel arch more closely than that of a similar free-standing arch. These passive pressures are reactions developed through outward deflection of the tunnel liner. Thus, the outward moving portions of a

Jan 1, 1979

By Robert A. Jankowski, J. Drew Potts

By implementing various mining practices, mine operators can reduce the respirable dust exposure levels of the roof bolter and the continuous miner operators. The Bureau of Mines has developed a computer program, entitled AMP (Alternative Mining Practices), that gives a quantitative comparison of these reductions. The alternative mining practices and their corresponding reductions in dust exposure levels that are evaluated by the program include a remote control continuous miner, a half-curtain ventilation system, two auxiliary fan-tubing bypass ventilation systems, a modified cutting sequence, a comparison between single-split and double-split ventilation networks, and a comparison between exhausting brattice and exhausting tubing. Descriptions of each of these mining practices are included in the report. The report also includes a hypothetical case study to show how AMP enables mine operators to select the technique(s) that is best suited to their particular needs. AMP is a compiled basic program that has been designed to run on computers with a DOS version 2.0 or later operating system. It includes high resolution graphics (640 X 200 dot positions) designed to run with video boards that are functionally compatible with the IBM Monochrome/ Printer Adapter. Graphic screens are selected from menus, and can be bypassed if the computer is not equipped to handle high resolution mode. Their primary function is to show proper implementation of the mining practices evaluated by the program. This package requires a minimum of 256K bytes of RAM. (Reference to specific products does not imply endorsement by the Bureau of Mines.)

Jan 1, 1987

By Felix Schmid

ABSTRACT Lateritic bauxite deposits of economic size and grade in Sierra Leone occur on granulites of the Kasila series. The high grade trihydrate ores of Mokanji are exploited by SIEROMCO since 1964. Remaining reserves are small (2 million tons) and operation moved over to the Gondama deposits of similar grade. Port Loko bauxite reserves are estimated at 100 million tons and are of relatively lower grade. It is planned to treat this ore locally into alumina. Guinea's bauxite reserves exceed those of any other nation. They occur as hard lateritic bauxite covers on plateaus of the Pre-Cambrian sedimentary formations and on doleritic intrusions. The genesis is still controversial. The Sangaredi mine has produced high grade ore for the last 10 years. Friguia exploits a relatively lower grade ore at a rate of about 2 million tpy to be treated in their local alumina plant. Kindia ore is mined at a yearly rate of 2,5 million tons since 1974. Untouched reserves at Ayékoyé and Tougué/Dabola are estimated at 6,000 million tons.

Jan 1, 1984

By Joseph B. Novak

In the last decade or so, the importance of effective preventive maintenance controls and practices has taken on a new and accelerated emphasis. Advances in technology and changes in equipment and product designs impose more precise and demanding standards of quality, productivity and customer service at a very rapid pace. Daily, it is becoming more apparent that in order to fulfill current requirements, existing manufacturing practices and associated control programs must also be upgraded and expanded. This is particularly true in the field of maintenance services. As production and quality standards become more demanding, effective equipment maintenance takes on more importance and becomes more difficult to sustain. In modern plants, the failure of a single equipment component can shutdown a complete production line causing interruptions to operating and shipping schedules that result in costly downtime, dissatisfied customers, and reduced profits. These costly experiences can be minimized with an effective maintenance program that provides maximum equipment reliability and minimum downtime and readily adapts to revision and change. A significant feature of an effective program is the provision of controls over activities generally identified as

Jan 1, 1971

By M. E. Mellado

In this paper, we present an a posteriori validation of a heap leaching analytical model using sensitivity analysis. The model is suitable to represent the process of heap leaching of solid reactants from porous pellets and is based on a combination of the leaching kinetics at two levels: particle and heap. The validation is simple, and a sensitivity analysis can easily be performed. The simplicity of the analysis provides insight into the control and optimization of the heap leaching process without strong mathematical complexities. The model and the corresponding sensitivity analysis include the effects of heap height, particle sizes, flow rates and several operation-design variables. Using a case study, we discuss the importance of model validation based on sensitivity analysis. We also comment on several choices for optimizing the process. We had three goals in this work: a posteriori validation, highlighting the importance of model validation and providing insight into optimization choices. We can conclude that the model has good internal logic and there are no extra variables; i.e., all of the variables in the model are necessary.

May 1, 2012

By R. Pakalnis

This paper compiles the research work conducted by the Spokane Research Laboratories in the investigation of shotcrete within underground mines to the applied design of ground support for the operator. It looks at the design methodology in terms of employing shotcrete as a fabric to confine the rock mass between the individual bolts as dictated by empirical charts. The failure mechanism in terms of its implication on design is presented with respect to the design of 6m wide tunnels for temporary and permanent openings within weak rock masses. This is reflected by field observations that relate laboratory tests to the onset of failure for the operator in order to provide guidelines for design and monitoring. This is coupled with guidelines for safe entry in terms of cure times as well as the understanding of the behaviour of the shotcrete in terms of fibres and the overall strengths that result with respect to the design of the mine openings. This enables the operator to better understand his workplace thereby provide a safer work environment.

Jan 1, 2010

By Douglas H. Bolton

In recent years, equipment manufacturers have been busy developing remote control systems to catch up with the sophistication and efficiency of continuous miners. Now the tables are turned, and manufacturers are undertaking the new challenge of upgrading, refining and equipping continuous miners to take full advantage of the capabilities made possible by modern, successful remote control systems. Because the operator can safely advance the miner farther without pulling out for roof bolting, continuous miners now need to be equipped with means of complying with correct face ventilation, dust suppression, methane detection, diffusion and improved lighting. Some of the exciting possibilities being developed to catch up with remote control include feedback controls using laser beams as datum points, coal sensing devices with feedback signals to show the operator what the machine is doing, show where it is relative to the coal seam, how hard it is working, and more sophisticated use of cyclic control. Mining machinery manufacturers have accepted the new challenges, and faster, safer mining procedures are already in sight.

Jan 1, 1975

By James D. Bennett

During the past decade many U.S. industries have realized the importance of a total loss control program; the bituminous coal mining industry is no exception to this trend. Oftentimes, we realize that the circumstances surrounding a "near miss" (an incident which does not result in personal injury or property damage) are practically identical to those associated with a fatality, disabling injury, or major property damage. And, many organizations suffer enormous financial losses in cases where no one is injured or property damaged but costly delays in production result. Detailed analyses of both injury and non-injury cases can provide valuable input into those engineering, behavioral, and management controls that are necessary to prevent their recurrence. The purpose of this paper is to describe a comprehensive loss control surveillance system (LCSS) that will enhance management control in preventing personnel, property, and production losses, thereby, maximizing profit. The next section describes the components of this LCSS. Then, we present one practical example of how this valuable management tool can be used to minimize loss through safety and training programs.

Jan 1, 1985

By Armin C. Supp

Since 1975, about a dozen high capacity flotation plants have been installed in the Ruhr district. Depending on the size of the preparation plants, the design capacity of the flotation section is between 100 - 150 t/h. The flotation units generally comprise rougher and cleaner stages in which 5 to 6 or 4 to 5 agitators respectively are arranged in line. The unit volume allocated to each agitator is up to 16 m3. The type of flotation machines, the design of these plants and their instrumen¬tation and control equipment are described in detail. The run of mine coal in the Ruhr district is characterized by a wide variety of the volatile matter. Generally, a distinction must be made between coals with more than 30 - 35% V.M., which are preferably used in power station, and coal with lower V.M. content, which are preferably used as coke-oven feed. The difference between these coals in respect to grain-size distribution, ash cotent and flotation properties will also be described in detail.

Jan 1, 1985

By Homer S. Anderson

To clarify what r mean about this long title, I would like to define the term technology. A standard definition of the word "technology" is "a technical method of achieving a practical purpose". Incidently, another definition of the term is merely "technical language". The same dictionary defines the word "technology" as "having a special, usually practical, knowledge of mechanical or scientific subject." Naturally, the practical purpose of the subject with which we are concerned is solving of problems we encounter in the mining industry. I might further describe the subject of this discourse by defining the term "manager". An old definition, "one who dispenses the duties of his position with care and economy." In line with the above definition most of the technology with which we in the mining industry are confronted with deals with some form of cost reduction. This may be related to the speed of doing an operation or to saving of labor or supply costs. These can be improvements of an existing method or the result of new processes or inventions, such as new machinery.

Jan 1, 1974

By J. Manrique, B. Bustamante, P. Altamirano, J. Mendoza, J. Reyes

With no doubt, Peruvian mining potential is great as well as the energetic one. Unfortunately, this potential is threatened by social unrest. Several methods and strategies from different standpoints have been rehearsed with respect to unrest in Peru, however, the problem goes on without getting the right conflict interpretation and most of all, effective solutions are not achieved. The mining unrest dates from ancient times and has not always had the same stages nor the same demands. In the 20´s and 30´s, conflicts focused on workers’ rights and demands. In the 70´s, conflict focused on mines nationalization that were under foreign control. In the 80´s, conflicts took place because of requesting better wages, better working conditions, better mining profits distribution and more investment in communities that surround mining projects. It is very important to highlight those transversal demands such as land purchase, agricultural property, impacts and water reduction as well as pollution, impact on water systems and disappearance of springs have always been present over the historical period.

Mar 2, 2022

By K. P. Pavlich

Strategic planning, including the process of developing competitive strategy, is an integral part of all organizational management; from one person operations to multi-national Fortune 100 firms. The structure of that process varies from decisions and direction based upon one person's intuition to the integration of multiple strategic planning groups from each of a firm's many business units. Everyone has heard interesting strategic planning stories such as the railroad industry's long term failure to realize that they were in the transportation business and not the railroad business, the decision to "give away the razors and sell them the blades", Caterpillar's "SOQ NaP" campaign (Sell On Quality, Not On Price), or the tanker industry's eventual realization that by better managing turn-around the firm could control their largest single cost: depreciation. It is important to remember that very few strategic planning decisions are going to become Harvard Business Review case studies. That fact does not, however, diminish the need for understanding the firm's business, and actively planning how it is going to remain in business in the future!

Jan 1, 1989