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By Charles L. Allie

In June, 1980, Reserve Mining Company completed a 370 million dollar construction project which included process modifications required to reduce the silica content from nine to five percent by weight and increase the iron con- tent of Reserve's pellets from 62.5 to 65.8 percent by weight (dry basis); process modifications and additions required to implement "best available technology" water quality controls; and installation of "best available technology" air emission controls. The new process began operation on June 24, 1980 and is being optimized to meet design objectives. Dry cobbing, fine screening and flotation additions to the concentrating process have reduced the silica content of Reserve's pellet from nine percent to five percent by weight. The process reclaims and reuses all process waters, stores all tailings in a zero discharge tailings basin and meets all air emission standards.

Jan 1, 1980

By Robert T. Chapman

Many of us are privileged in that we have witnessed the transition from mining methods used in the first quarter of the twentieth' century to those practiced today. In the late Twenties, for example, many mines still used hand mucking methods. In the middle Thirties, more than one large metallurgical limestone quarry still used the 4 cubic yard railway steam shovel formerly in use at the Panama Canal. Mules could occasionally still be found underground, where they provided the-main-source of motive power. Within the last decade, and even within the past five years or less, great improvements have been made in blast-hole drilling, ore loading, and ore hauling equipment. Industrial demand for minerals can be expressed in exponential terms as compared to that at the turn of the century. Even marine mineral resources are receiving accelerated attention. One overall result is that larger and lower grade orebodies can be exploited at a profit. This profit must be made despite, for example, a static monetary price for gold, and despite the continual cost escalation involving labor, materials, supplies, and equipment. Accordingly, the application of the necessary degree of knowledge and judgment required to meet production, cost, and profit goals is paramount.

Jan 1, 1966

By Donald R. Williamson

The Cyprus Pima Mining Company's open pit operation was started in 1957 with the normal assumption that the ore reserve estimate was accurate within an acceptable range of values. At that tine reserves were law - volume (+10 million tons) and high grade (+1.5% Cu). Several periods of growth have brought the operation to its present production level of 55,000 tons per day of ore and +125,000 tons of waste. Over the years, a number of attempts to refine and polish the ore reserve figures have been made using a variety of established standard procedures. None of these attempts have produced results which are totally satisfactory, particularly when comparisons are made between ore reserve estimates and short to medium range production figures. Other refinements were tried using adaptations of established methods combined with computer modeling techniques. The resulting mine-model ore blocks were an improvement but they still tended to show too match tonnage of mill feed, often at too low a grade. One attempt at Kriging had only limited success. Statistical studies of operations data revealed relationships which could be used to subdivide ore blocks in much the same way as they are actually mined. Comparisons thus far between these newly developed ore blocks and production data show that the new method of evaluation yields excellent results. A new, better procedure for estimation of ore reserves apparently has been developed for the Cyprus Pima deposits. The specific procedures seem likely to have direct application to other, similar operations. The methods used to develop the procedures could be of value to still other operations.

Jan 1, 1976

By Joseph W. Johnson

General Electric introduced electric drive systems on 85 ton Off-Highway mining trucks in the early sixties. Due to favorable economics, trucks have increased in size to handle larger payloads. Series Motorized Wheel systems were developed to meet this demand. When the technology was available, General Electric switched from use of Series motors to separately excited motors with the added benefits of static exciters and simplified control. Over 20 years of electric drive experience have been incorporated in the STATEX drive systems, which covers truck sizes from 85 to 220 tons. This paper traces the drive system developments from the early stages to the present and takes a look at what's ahead.

Jan 1, 1983

By Adam Bedell, Jack Raymer, Brad Crenshaw

Tunnel contracts often include provisions for pre-excavation probing and grouting for areas ahead of the tunnel heading. If grouting triggers are met, tunneling stops, and grouting is performed. There is substantial variation within the underground industry on what criteria are applied to the grout verification hole that is drilled post-grouting and before excavation resumes. The criteria for determination of the effectiveness should be dependent on the geology and local hydrogeologic conditions. The purpose of this paper is to present specific criteria that can be used by a practitioner to determine whether tunneling can resume or if additional grouting is required.

Dec 1, 2022

By R. H. Thorpe

In the earliest days of mining coal the obvious method was by bord and pillar working. Longwall in Britain developed from this as an expedient to overcome bottlenecks arising from ? 1) increasing depth of seams causing roof control difficulties; and 2) ventilation problems. This system became almost universal particularly in the thicker seams, where faces of up to one mile in length were not uncommon. Coal getting in these faces was usually by pick and shovel, filled into small waggons of up to 15 cwts capacity. These waggons ran on rails laid alongside the coal face and were often taken away from the face to the main haulage roads by horses. The roof was supported by rigid props and the wastes were normally controlled by strip packing. This system of mining was very flexible and worked well down to sections of about 3'6"

Jan 1, 1976

By Steven Brown, Richard Stephenson, Richard Partch, Hongyu Wang

Filler technology has enjoyed a revolution in attention and achievement in the past half century. The genesis of the advancements is greater find a mental understanding of the synthetic chemistries for and physical properties of colloidal matter and instrumentation capable of characterizing particle size, shape and surface features. Several advanced chemical methods for processing powders are now employed in ceramic, electronic, imaging, medicinal and plastic technology. This presentation will highlight solution phase synthetic methods for in situ coating of fillers such as SiC, Al2O3, AlN and SiO2 and some properties of the product solids.

Jan 1, 2003

By Robin J. Hickson

El Abra is one of the world’s premier copper de-posits. The project is located in northern Chile, 140 km (87 miles) inland from the Pacific coast. It has the same geologic age and structural setting as the world-class Chuquicamata copper mine located 42 km (26 miles) to the south. The current development plan for El Abra extracts798 Mt (879 million st) of high-quality oxide ore. This will require building a solvent extraction/electrowinning(SX/EW) facility that can produce 225 kt/a (248,000stpy) of cathode copper. This will make El Abra the largest SX/EW copper operation in the world, and the world’s seventh-largest copper producer.

Jan 1, 1996

By Harrison H. Roberts

A. We are aware that many who are in the audience have perhaps heard before some of the material which will be presented. Since our firm is more closely associated with the heavy construction industry our experience is more oriented in that direction. Notwithstanding this, the subject your program committee has asked us to present centers mainly in the earth-moving field. We find a common denominator between say, the stripping of a site to uncover an ore-body which will be developed by open-pit methods, and that of excavating & transporting materials for an embankment dam, airport or other project. Both are earth-moving problems and we offer for your consideration a means of determining the most favorable method, equipment selection and resultant cost. We do considerable studies involving rock excavation for tunnels, underground powerhouses, inclined and vertical shafts for penstocks, muck-removal, electrical cable & other related underground work. Hence, we believe we speak the same language.

Jan 1, 1972

By Peter V. Avotins

During last year's AIME meeting in New Orleans, Deepak Malhotra and I were discussing some of the topics that would be presented in this Symposium. It seemed appropriate that along with papers on specific reagent and flocculant types, we should address research management aspects of new product development. This development is a long, arduous task that requires a significant technical and fiscal commitment by the chemical company and potential users. A flow chart depicting the research process is shown in Figure 1. The sequence of events are plotted on an undefined time line. Our experience has shown that it takes 3-5 years to complete a typical reagent development project. A new project starts with an idea of how to do something better. The ideas range from relatively simple product modifications to opportunities created by technological change. An example of this is the use of flocculants in tailings operations to close the water recycle loop. The change was brought about by the need to conserve water and comply with environmental statutes. The result was the development and wide-spread use of synthetic polymers to help in solid-liquid separation. More recently the ups and downs of oil prices have led to development of coal water slurries as an alternative to fuel oil. The slurries contain high levels of chemicals (up to 3%) to insure proper stability and burn characteristics. There are technical changes under way right now that may lead to ideas for other new products. One exciting source of new technology is the ability to manipulate genetic material of microbes to select for specific capabilities. This has evolved by leaps and bounds over the past 5 years. Biologically assisted leaching and removal of wastewater impurities are two possible end uses. I'm sure that there are many others. The ideas can originate anywhere and are often half-baked at first, but to lead to new products they must be refined to provide project definition and eventually a research plan. A chemical ,development project cannot be started without approval to commit the company's resources. The internal selling job is often very difficult. The company must see clear financial benefits in order to launch efforts that may not pay off for many years. It is critical to project the total market, profitability, eventual market share, and timing of introduction of the new product. There is much uncertainty in this and the research manager is often skating on thin ice to retain his credibility. Once we obtain support from upper management, the research team is assembled to start the project. The teams generally consist of organic chemists, research metallurgists, and technicians. They have access to analytical scientists and technicians for surface and analytical chemistry. The projects are often augmented by help from university staff and consultants. This is particularly true where there is a need to develop fundamental understanding of the technology in addition to synthesis of chemicals. The project now proceeds along two lines. First, there is an emphasis on understanding the prior art. Extensive literature and patent searches are undertaken to provide research leads and to keep from "reinventing the wheel" and infringing on someone else's patent. The scientists and technologists are qualified to conduct computer-assisted library searches. This process usually uncovers 80-90% of the relevant information. The remainder is very much harder to get and requires the help of professional library search staff with scientific backgrounds. Along with literature searching, the team begins synthesis of new compounds. These are screened by use of techniques such as microflotation or filtration in a Buchner funnel. The scientists are looking for the direction of response as they modify structural features . Inevitably, a large number of candidates reach the next stage, a laboratory bench test. At this point it is possible to set up a research plan and use project management techniques to monitor progress. The bench tests are conducted in larger equipment, usually requiring 100-1000 grams of test substrate. Typical laboratory flotation tests are run in Denver or Wemco cells.

Jan 1, 1986

By J. W. Hawkins, K. B. C. Brady, M. W. Smith

The Pennsylvania Department of Environmental Protection (PaDEP) has been issuing surface mining permits since 1984 that authorize remining in areas that will affect preexisting pollutional discharges. These permits require the mine operator to employ best management practices to reduce pollution loading from abandoned mine discharges. A total of 110 completed mining operations with 233 discharges were evaluated to determine the impact to water quality. Overall, acid loading from these discharges was reduced by 7, 200 kg (15, 900 lbs) per day or 61%. Metal loadings were also reduced. For acidity, 49% of discharges improved or were eliminated, 52% showed no significant change and fewer than 1 % got worse. Loading reductions resulted from a combination of reduced concentrations and lower flows.

Jan 1, 2003

By K. L. Kayler

The Bardon Trimount, Inc. stone quarry in Ashland, Massachusetts was the recent subject of a quarry closure review report. The quarry produces aggregate using standard drilling and blasting techniques. Stone is processed at an on-site plant. Noise monitoring data collected during the closure review indicate that the quarry generally operates within the quiet range. There is a decrease in noise while the quarry is not operating. Levels of dust associated with the quarry are low. Unpaved roadways are the greatest contributors of fugitive dust associated with the mining operation. The quarry cannot be seen from any homes within the town of Ashland, except during the winter months. The visual impact of the quarry on surrounding properties is minimal. Further quarry development is likely to reduce visibility of the quarry from some areas.

Jan 1, 1995

By T. J. Lutz, S. Gallagher, J. R. Srednicki, J. J. Sammarco

The Illuminating Engineering Society of North America reports that an underground mine is the most difficult environment to illuminate (Rea, 2000). Researchers at the U.S. National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) are conducting ongoing studies designed to explore different lighting technologies for improving mine safety. Underground miners use different visual cues to escape from a smoke-filled environment. Primary and secondary escapeways are marked with reflective ceiling tags of various colors. Miners also look for mine rail tracks. The main objective of this paper is to compare different lighting types and ceiling tag colors to differentiate what works best in a smoke-filled environment. Various cap lamps (LED and incandescent) and lasers (red, blue, green) were compared to see which options resulted in the longest detection distances for red, green and blue reflective markers and a section of mine rail track. All targets advanced toward the human subject inside of a smoke-filled room to simulate the subject walking in a mine environment. Detection distances were recorded and analyzed to find the best cap lamp, laser color and target color in a smoke environment. Results show that cap lamp, laser color and target color do make a difference in detection distances and are perceived differently based on subject age. Cap lamps were superior to lasers in all circumstances of ceiling tag detection, with the exception of the green laser. The incandescent cap lamp worked best in the simulated smoke compared to the LED cap lamps. The green laser was the best color for detecting the tags and track compared to the red and blue lasers. The green tags were the easiest color to detect on the ceiling. On average, the track was easier for the subjects to detect than the ceiling tags.

Jan 1, 2013

By R. E. J. Putman

The, principle purpose of applying control to any process is to improve -its profitability. Even when considering the impact of a plant on its surrounding ecology this is still, true, since the sanctions felt most immediately from violations of the regulations are the economic penalties or fines which result. 'Economic performance can be improved within a plant in several ways. Steps can be taken to cut the cost or quantity of resources (power, water, steam, reagents) consumed per ton of throughput. Alternatively the operation of the plant can be changed so as to increase product yield per ton of throughput. Or the cost of labor and plant overhead per ton of product can be reduced by raising the total 'throughput, assuming-that the increased amount of product can be sold for the same unit price. In designing a program to improve plant performance, all three routes should be borne in mind. To maximize the return on investment over a longer period, it is also desirable to set up a comprehensive plan of improvement, equipment being specified at each step in the implementation so as to ensure that it fits in with later requirements later implementation being either by means of modular additions or by having the necessary interfaces built into the original equipment. It is much cheaper in the long run to buy features which have been factory-installed, than to have to make provision for their later addition in the field. This paper examines some ways of improving plant performance by the application of various process control techniques using both analog and digital con¬trol equipment. A general philosophy of application is suggested and specific examples described.

Jan 1, 1972

By M. Li, J. K. Thompson, A. S. Azman

Powerful mining systems typically generate high-level noise that can damage the hearing ability of miners. Engineering noise controls are the most desirable and effective control for overexposure to noise. However, the effects of these noise controls on the actual hearing status of workers are not easily measured. A tool that can provide guidance in assigning workers to jobs based on the noise levels to which they will be exposed is highly desirable. Therefore, the Pittsburgh Mining Research Division (PMRD) of the U.S. National Institute for Occupational Safety and Health (NIOSH) developed a tool to estimate in a systematic way the hearing loss due to occupational noise exposure and to evaluate the effectiveness of developed engineering controls. This computer program is based on the ISO 1999 standard and can be used to estimate the loss of hearing ability caused by occupational noise exposures. In this paper, the functionalities of this software are discussed and several case studies related to mining machinery are presented to demonstrate the functionalities of this software.

Jan 1, 2016

By J. Diao

In order to understand the flotation kinetic behavior of coal and associated mineral matter, a detailed investigation was conducted in a 2-liter Denver flotation cell using three high sulfur coals at three feed sizes, minus 28. 100 and 200 mesh. Subsequently. the flotation products were sieved into different size fractions and analyzed for their ash and pyritic sulfur content in order to delineate the effect of particle size on the rate at which each constituent floats. The results were tested with several different flotation kinetic models and the best model for coal was then chosen. The flotation rate constant and the ultimate recovery calculated from a kinetic model were used to delineate the effect of particle size, collector (dodecane) and frother (MIBC) dosages on the flotation kinetics of coal, ash and pyrite.

Jan 1, 1992

By Earl L. Rau

Although the Sagasca deposit has been known for 76 years, the property was never put into successful operation because of various adverse factors including low market price for copper, legal entanglements, unsuccessful financial arrangements, and an inadequate metallurgical process. Late in 1963, Continental Copper & Steel Industries, Inc., obtained legal control of this property. Since that time there has been a concentrated effort to complete the necessary mine appraisal, process development, and engineering design, and to solve the legal and financial problems to bring this property into production.

Jan 1, 1970

By Jason Clarke, Glen Trainor

As the mining industry faces increased challenges with declining ore grades and harder to access deposits, operating mine sites in an environmentally responsible and economically viable manner will require innovations that improve efficiency in energy logistics, and automation. Technological advancements in mining have been successful primarily because of the willingness and capability of these solutions to share information with one another, for example OEM payload systems sending information to Fleet Management Systems, and in turn Fleet Management Systems interfacing to ERP systems. To promote and facilitate the sharing of data, there has been a push towards open standards with initiatives led by organizations like ISO, ISA, EMESRT, and GMG. These efforts are aimed at creating a more collaborative and interoperable environment within the sector. However, when it comes to implementing autonomous solutions, a different trend dominates— closed-stack solutions. These closed stack solutions not only prohibit a mine site from selecting best-of-breed solutions, by blocking the competition from entering the market, they also risk slowing innovation that could help overcome the challenges the mining industry faces. Open Autonomy, an internationally published standard that allows any FMS to work with any Autonomous solution, breaks this closed-stack approach and invites competition from other industries. This competition comprises of autonomous suppliers from other industries and manufacturers of smaller, civil-sized haul trucks. The availability and capabilities of these smaller-sized autonomous haul trucks will help tackle the challenges of responsibly and economically mining lower quality ore grades and mining harder to access deposits.

Feb 1, 2024

By James F. Fraser

Construction of a major linear project in any environment is difficult, at best. Construction of a major linear project which includes major subway elements, both cut and cover and tunneling, in the center of an urban environment, approaches the impossible. I believe such a project would be impossible for a private company or a privately owned utility for a variety of reasons. The major two reasons are the funding necessary for such massive projects and the myriad of individual interests associated with private ownership of land. Such projects are possible in the public sector only because the need for the project... as is the case with mass transportation in Atlanta. . .overrides the profit motive. Without the profit motive, private companies, whether utilities or not, are precluded from practical interest in the development of any project. While it is safe to conclude that a profit-oriented business would have no practical interest in developing such massive projects as may include major tunnels, it would be useful, I think, to compare some of the significant differences between private profit-oriented businesses, and an agency, or Authority, such as MARTA, in building a major linear project. SLIDE 1. Comparison of a Private Company and a Public Agency [Item Private Company Public Agency Simplified To make a profit To provide a pre Purpose scribed service]

Jan 1, 1979

By P. C. Dagneau

QUEBEC CARTIER MINING COMPANY was incorporated in 1957 to explore and develop low grade iron are deposits in Northeastern Quebec. Four separate deposits were located and identified as being of ore quality and size to support commercial development. Said deposits were located at Lac Jeannine, Mount-Wright, Fire Lake and Mount-Reed. In 1970, in preparation for the replacement of the depleting Lac Jeannine are reserves, construction of an SS-mile railway extension was initiated, towards the newly selected mine site at Mount-Wright. This orebody was selected because the physical and chemical characteristics of the ore were very much similar to those of Lac Jeannine, as well as its huge reserves, estimated at more than one billion tons. In addition to the railroad extension, a mine, concentrator and related facilities were constructed and the new town of Fermont was created. Total investment for the Mount-Wright project exceeded $700 million and initial production commenced in 1976. Quebec Cartier is presently (1992) the leading producer and seller of iron ore in North America at 15,5 million tons and employs some 2,300 people.

Jan 1, 1993