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By L. Adler

When systematically compared to other engineering fields, mining engineering is distinctive in 1) having a total systems concern. 2) dealing with encumbered space and 3) requiring full spectrum practice. The total systems concern results from having to design and then co-ordinate in space and time several major systems: excavating and bulk handling, ground control, life support and normal support. This requirement favors a generalist rather than a specialist approach. In coping with encumbered space especially in underground coal mining, the uncertainties of geologic conditions are compounded by tightness, roughness, remoteness and hazards. Into this difficult setting the total systems * complex is "stuffed," adding congestion and interference. Because of significant ground deterioration a flexible "rapid in-out" approach is usually vital to mining. Full spectrum practice arises from the need to manage, as well as to plan and design, a labor intensive operation. Since market conditions can also fluctuate most aspects of administration are needed in many respects, mining engineering functions relative to civil engineering in a way similar to industrial to mechanical engineering, with encumbered space being crucial. On this basis stress is placed on: 1) personal relations, 2) field work and 3) entrepreneurship, viewing time as money. Specific recommendations for improving engineering, safety and management and leadership are made. Since most new deposits are marginal, by applying these recommendations with high technology they could possibly now be mined on a widespread basis.

Jan 1, 1985

By Verya Nasri, Jaeseoung Lee, Ashish Bhargava, Shashank Gupta

This paper presents the unique design and construction challenges for the Technoparc Station, located in downtown Montreal as a part of Réseau Express Métropolitain (REM), a light rail rapid transit system. The station is located 15 m below the street with rock-bearing secant pile wall as the primary structural system working as both the retaining and gravity structure. The paper highlights the challenges related to the support of excavation structure, invert slab resisting high hydrostatic forces, waterproofing tightness etc. It also focuses on the importance of Building Information Modeling (BIM) in underground tunneling projects for effective coordination, clash-free, optimized design and costs.

Jun 13, 2021

By D. S. Parasnis

The early beginnings of mining geophysics in Sweden can be traced back to the reign of queen Kristina in the 17th century. The mine compass, consisting of a freely suspended magnetic needle in a casing, was in use certainly by 1640 and probably earlier for locating iron ore deposits. Whether the mine compass was a Swedish invention or not is an unsettled question since the possibility cannot be overlooked that the celebrated Nürnberg compass-makers of the 16th century may have constructed it for the first time(1). Be that as it may, the mine compass was very extensively employed in Sweden for more than two centuries and met with spectacular success in locating magnetic deposits under shallow overburden. Occasionally the diligent prospector would even be rewarded with a pyrrhotitebearing sulphide deposit, as witness many old sulphide-ore pits and some mines still in operation from the 17th and the 18th centuries. The mine compass measured only the orientation of the Earth's magnetic field and not its strength. Although it was improved in construction and sensitivity over the ages, no great strides were made in magnetic prospecting after the initial discovery of the use of the compass until Gauss, omnipresent in 19th century physics and mathematics, showed with the assistance of Weber how the strength of a magnetic field could be determined.

Jan 1, 1975

By K. F. Unrug

The identification of the major subsidence areas in the Western Kentucky Coal Field has been made to distinguish the subsidence phenomena on the basis of geographical location Further, this identification process is based upon selected critical geological, topographical, and mining features in the coal fields. The proposed identification of the regions is derived from a comparison of the subsidence potential in a particular area. The most likely severe subsidence areas are compared to those with the probable low subsidence severity. The combination of certain geological and mining parameters involved allows for the derivation of a classification of the subsidence potential. It is recommended that further site specific studies should be performed on this area.

Jan 1, 1986

By A. D. S. Gillies

Loss of visibility due to the occurrence of atmospheric fogging in underground mine airways can lead to a reduction in travel times and loss of production efficiency, an increase in the frequency of vehicular and foot traffic accidents and difficulty in checking rock surfaces for instability and loose material. Where hot and humid surface air meets colder underground air, conditions for fog formation nay be present. Further, suspended particulate matter from diesel exhausts or stoping operations together with slow movement of air along passageways nay contribute to formation. The study describes an investigation being undertaken with the cooperation of Kennecott's Ozark Lead Company to identify causes of the problem.

Jan 1, 1982

By T. W. Camm

"We hear all the time about the value of hard work and perseverance, and the part they play in the professional life of successful people. What we do not hear so much about are the many professionals who work hard and persevere, yet never seem to quite reach the level of success they aim for. Some current authors are beginning to give more attention to the part luck/black swans/outliers play in success. This is not a new phenomenon, Machiavelli had a lot to say about it back in the Renaissance. So how can knowledge of this dynamic help in a modern organization? INTRODUCTION Work hard and you will succeed. Go to the right school, major in the right degree, study hard, and get a good job. Look at the lives of successful people, and do what they do. Be all that you can be. You can be anything you want to be. Really? Those who are successful always get attention, people want to know what they did to reach such a high position. Invariably, at least part of their narrative will include hard work, wise insight, taking advantage of opportunities, etc. If they are of a more generous nature, they might also allow that building the right friendships and collaborations also played a role. All of this may be true; what we do not often hear are the stories of those who did all of these very same things, but did not find success. An example from pop culture: The Voice. I have watched this show occasionally the past couple of years. One of the things I like about the show is that the initial screening of contestants is based solely on their singing voice (hence the name of the show), and not on their appearance. At the time of this writing (early November), the judges have just finished elimination rounds for their final teams to go on to the live shows. Here is my point—in almost every case the judges agonized over choosing who would go forward and who would be eliminated. And the reason is because all of them are really talented singers. It is impressive how gifted they are. At the end of each season, only one is declared a winner, out of that gifted pool of singers. When you hear their stories, they are all talented, hard-working individuals sacrificing for their art. And as far as I know, none of them has ever become a star. Hard work, dedication, sacrifice, talent—sometimes it is enough, sometimes not. I will be looking at the part uncertainty/luck/black swans play in our lives, but I want to make it clear at the beginning that I am not saying everything that happens to us is out of our hands or beyond our control. Taleb makes this same point (2007, p. 52): “This problem is chronic: if you tell people that the key to success is not always skills, they think that you are telling them that it is never skills, always luck.”"

Jan 1, 2017

By Verne Huser

The intensity of environmental conflict, the delays and legal battles that have marked the 1970's suggest the need for additional processes to resolve environmental disputes. Our present means frequently fail to address the real issues separating individuals and institutions. They are primarily adversary processes that foster polarization and reduce cooperative efforts. At the Office of Environmental Mediation, we have no quarrel with adversary processes nor with polarization, for both serve as important spurs to necessary change. We do seek cooperation among parties at a point where there can be a realistic expectation of success in facilitating a resolution of their mutual differences.

Jan 1, 1979

By Evan J. Owen, Virginia T. McLemore

of high specific gravity, resistant minerals that form from mechanical concentration by waves, currents, and winds in marginal-marine environments. These sediments are enriched in critical minerals such as titanium, zirconium, and REE. Cretaceous beach-placer sandstones are found in the Colorado Plateau of northwestern New Mexico. Originally discovered by airborne radiometric surveys for uranium in the 1950s, these beach-placer sandstones are being re-examined with modern methods as potential sources for critical minerals. Selected beach-placer sandstones have been sampled, mapped with ground radiometric surveys, and analyzed with whole-rock and trace element geochemical methods. Mineralogy is being determined with optical methods, XRD, and EMPA. Zircon, rutile, ilmenite, and monazite are the primary heavy minerals of interest found in the studied deposits. Initial results show that the sandstones contain up to 1.4% total REE, 29.4% TiO2, and an estimated 4.9% ZrO2. Chondrite-normalized REE diagrams show distinct light REE and minor heavy REE enrichment, as well as pronounced negative Eu anomalies for each deposit.

Feb 1, 2024

By Thomas E. Ban

D-LM at Mobile The qualified success of iron ore pelletizing processes has influenced considerations for production of highly beneficiated fur¬nace charges. Such beneficiation would necessarily involve some forms of chemical and perhaps thermal conversion for production of prereduced pellets, preheated pellets, precalcined pellets, and perhaps pellets which contain all of the above features as preheated, prereduced, precalcined products. This type of furnace burden will be adapted within a new ironmaking process to be activated commer¬cially during the latter part of 196$ in Mobile, Alabama. This process will integrate a new pelletizing system with an electric smelting furnace and the pellets will be comprised of a composite charge blended from metallurgical proportions of iron ore, coal, and limestone. The plant as designed and constructed by McDowell¬-Wellman Engineering Company will feature the D-LM process and will be owned by McWane Cast Iron Pipe Company. It is significant to

Jan 1, 1968

By Byron R. Berger

Disseminated Au-As-Hg mineralization is localized along the Getchell Fault system at the Getchell Mine in north-central Nevada. Replacement ore bodies occur in Cambrian carbonaceous limestone and limy shale beds. Cretaceous granodiorite, dacite porphyry, and andesite porphyry dikes parallel the fault zone and are spatially associated with the mineralization. Hydrothermal alteration and mineralization occur continuously along 4-5 km of the fault system, and extend more than 1 km down-dip. Alteration consists primarily of removal of carbonate and deposition of quartz, pyrite, and carbonaceous material. Marcasite, sericite, kaolinite, calcite, barite, and fluorite are common. Gold content reaches more than 43 ppm in parts of the altered zones and averaged 9.3 ppm in the mined ore bodies. For the mineralized zones as a whole arsenic averages 0.28%, and occurs primarily as realgar, orpiment, and arsenopyrite. Mercury (22 ppm) is finely disseminated and mercury-bearing minerals are seldom recognizeable. Accessory mineralization includes antimony (100 ppm), copper (47 ppm) , lead (18 ppm) , molybdenum (10 ppm) , tungsten (16 ppm) , and zinc (50 ppm) . Geologic field studies and K-Ar dating suggest that the mineralization is related to a hydrothermal system produced by the granodiorite and related dikes.

Jan 1, 1975

By J. D. Goodrich

Success of The Carter Mining Company's safety program can be primarily attributed to "total immersion" of all operating and staff personnel in program design and implementation. Currently, the Company operates two surface coal mines in Campbell County, Wyoming. Total employment is about 440 and current annual production is about 15 million tons. The safety program has evolved from one which was administered primarily by staff personnel (the Safety Department) to one which requires active participation by line management and operating personnel. Lost time accident frequencies have declined from a high of 1.86 per 200K hours worked in 1978 to zero in 1982. Reportable accident frequencies have declined from slightly over 5 to slightly over 2 during the same period. Analysis of program results indicates that the most important achievement by the company has been to gain strong commitment to safe operation by all employees. It is important that program format and content be frequently changed and modified so that: 1) The requirement for safe job performance is communicated well and often, 2) The safe job performance message is trans- mitted in new and interesting ways, and 3) Operating personnel participate in design and implementation of the program.

Jan 1, 1983

By Judson G. Brown

In order to filter small amounts of fine slimy solids the reversible cake-filtration process was developed. The filterable solids contents lion in feeds can range from less than 1 ppm up to about 5%. The relative advantages of this process, are usually the greatest in the range of 0.05% to 1.0% filterable solids. Filterable solids that average in particle size about 20 microns& are non-compressible are very easy for this filtration process. Some feeds have been all sub-micron in particle size. A 1/8 inch thick cake is considered to be very thick. The usual cake is between 13/2 and 1/16 inch thick. A new line of injection molded plastic filter plates were developed for use with the reversible cake filtration process. The first commercial sized installation of this system was made 3 years ago in the Wakefield Y.M.C.A. swimming pool. Over 70 filters ranging in size from one plate to 63 plates have been produced. In addition to the process advantages there are the low cost and corrosion resistance advantages of the plastic plates.

Jan 1, 1962

By Leonard Sargeant

The Pocahontas Coal Field consists of eight mineable seams of low-volatile coal in southern West Virginia and Virginia. The deeper seams, especially the Pocahontas No. 3 and No.4 Seams, under heavy cover and below drainage are notoriously gassy. Methane in the Pocahontas Field is generally thought of as being confined in the coal itself, rather than in mud slips or clay veins. Furthermore, it is characteristic of Pocahontas coal to retain its gas until the coal is broken and removed from the solid. Because of this inability for gas to escape from unmined coal, entries developed around large blocks are seldom of significant value in bleeding off methane before pillar extraction begins. This is evidenced by the fact that it is not uncommon to find gas liberated during the mining of chain pillars and barriers which have been developed for several years. The Pocahontas Fuel Company develops almost all solid coal by conventional methods with shuttle car haulage. To provide the maximum productive capacity without compromising ventilation and safety requirements, the Company has adopted standards for ventilating 5, 6 and 7-entry sections.

Jan 1, 1960

By P. Somasundaran

Previous studies on semi-soluble minerals such as calcite (1) and apatite(2) and sparingly soluble minerals such as quartz (3,4) have given evidence for significant changes in their electrokinetic properties as a function of aging time. Such changes are relevant to mineral processing operations where the crushed ore particles might not have yet reached equili¬brium with the water that it is in contact with. In order that these changes be studied under controlled experimental conditions for long periods unattended or with fairly less intermittant attention, a streaming potential apparatus with an automatic streaming system was constructed. Also, a new streaming potential cell was incorporated into the system so that the effect of temperature, a variable coming into increasing usage in mineral processing operations(5), could also be studied. Conventional streaming cells(6) cannot be safely employed to conduct studies as a function of temperature since they have many glass joints that are prone to leakage, parti¬cularly under pressure, in the course of an experiment. This paper describes the new apparatus and some typical results that have been obtained with it far temperature effects.

Jan 1, 1973

By L. Adler

A fairly complex analysis is required to select, or evaluate a piece of excavating and bulk handling equipment and obtain its performance. At present there is little agreement as to what specific points should be considered, and even less on what procedure to follow. This paper provides both of these in a consistent and direct form. The analysis applies to all types and sizes of equipment from the bulldozer and the continuous miner, to the B.W.E. The importance of the equipment characteristics, job activities, and work conditions are stressed and separate analytical stems are established in a flow chart for these. They are combined using suitability tests in the following steps: 1) problem statement, 2) natural conditions, 3) suitability guidelines, 4) appropriate equipment types, 5) operational activities, 6) encumbered space, 7) geometric design, 8) equipment sizing, 9) failure and limits, 10) performance and consumption, 11) public policy checks, and 12) costs and profitability. Public policy and economics while considered throughout receive emphasis towards the end. The procedure is iterative, containing distinct feedback loops. Specifying the steps and sequence provides a necessary structure which has long been overdue.

Jan 1, 1983

By Alen Shibu Joseph, Arvind Rajnarayan Singh, Mudila Dhanunjaya Rao, Kamalesh K. Singh

In this article, the cementation of major impurities from zinc sulphate leach solution by the addition of zinc dust was studied by considering different parameters including time, mesh size, and percentage of excess zinc dust. The output obtained from various experiments was utilized for the design of experiments. A multi-level categorical factorial design with a quadratic model was employed during this study. Results were predicted to minimize the concentration of impurity metals in the solution by altering the parameters. Furthermore, these predicted results were validated by performing another experiment. Successfully, it showed that the predicted and experimental data values were close to each other. The predicted optimized values were 40 min, 100% excess zinc dust, and 300 mesh size for copper; 42 min, 100% excess zinc dust, and 300 mesh size for cobalt; 37 min, 100% excess zinc dust, and 300 mesh size for cadmium; and 34 min, 100% excess zinc dust, and 300 mesh size zinc dust for nickel. At these optimized values, the experimental results showed 99.99%, 55.7%, 99.6%, and 76.6% cementation efficiencies for copper, cobalt, cadmium, and nickel respectively. The statistical design of experiments for the effective cementation of impurities corroborates the economic feasibility of optimizing parameters for the proposed process.

Jul 18, 2022

By R. W. Smith

A number of investigators have studied the electrokinetic potential (?) of kaolinite as a function of pH. (1,2,3,4,5) These investigators all agree that the ? is negative except at quite acid pH values. The actual shapes of the curves reported by the several authors vary considerably. In spite of the general negative character of kaolinite the mineral has a rather high anion exchange capacity. (6,7,8) The cation exchange capacity is the lowest for the clay minerals. (6) It has been shown that anionic surfactants adsorb readily onto the mineral even up to neutrality, often in quantities exceeding the reported anion exchange capacity. (7,8) At least part of the anionic adsorption should be onto positive edge sites thought to exist on the mineral. (9,10) In the present study ? of kaolinite was measured as a function of pH using both the streaming potential (sp) and microelectrophoresis (m.e.p.) methods. In addition ? was measured at various pH values as functions of sodium dodecyl sulfate (SDS) and trimethyldodecylammonium chloride (TMDAC) concentrations. In some experiments decyl alcohol (DA) was added.

Jan 1, 1968

By Haydn H. Murray

Although alumina constitutes about ii percent of the earth's crust, it is expensive to separate and purify for the production of aluminum with the exception off the alumina in bauxite. The United states has a variety of non-bauxite resources that could substitute for bauxite, including high alumina clays, alunite, dawsonite in oil shale, anorthosite, and nepheline syenite. Each of these resources are discussed from the standpoint of geology, geography, processing, potential recovery, and environmental problems. Potential by-products include silica from clays, potash and sulfuric acid from alunite, soda ash from dawsonite, and soda ash and potash from anorthosite and nepheline syenite.

Jan 1, 1982

By Tim Neil, O&apos

Copper price rebounds A worldwide scramble for diminishing supplies of copper has pushed the red metal's price to more than $2.20/kg ($1 per lb), the highest level since 1980. The first nine months of 1987, world copper production was down 1% from a year ago, while consumption rose 7%. Demand has been fueled by economic strength in several countries, particularly Japan, South Korea, and Taiwan. The price has also been helped by interest rate declines that have prompted manufacturers to build up inventories. In addition, China is expected to be a major buyer in 1988 as it stocks up for its five-year industrialization plan. There appears to be no sign of any significant increase in copper supplies until later 1988 or early 1989. This means supplies probably will remain tight for some time even if world economic activity slows. Strikes and other production problems slowed world output of copper in 1987. As a result, copper supplies are the lowest they have been in 14 years. World inventories currently total 625 kt (690,000 st). That is not much above the 585 kt (645,000 st) level reached in 1974 when the price of copper rose to a record $3.84/kg ($1.74 per lb). This makes all the more interesting what Chile, the world's largest copper producer, has been doing lately. Chile has been the world's largest copper producer since 1982, when it overtook the United States. Table 1 shows Chile's copper grades, reserves, and production at its mines. Chile contains roughly one-fifth of the world's copper reserves. At present production rates, these reserves would last for more than 100 years. In 1986, Chile produced 1.4 Mt (1.5 million st) of fine copper, up 3%. Chile accounted for 17% of the world's copper output.

Jan 1, 1988

By Stanley C. Suboleski

The increase in productivity which has been achieved in mining during the past two decades has been attained largely through the replacement of manpower with electrical power. Power demands should continue to increase, requiring electrical distribution systems to be well planned to avoid inadequate voltage levels caused by underdesign and excessive costs resulting from overdesign. To aid the mining electrical engineer in designing proposed power systems or analyzing changes to existing systems, a digital computer program has been developed. This program will analyze alternating or direct-current networks with up to 10 voltage sources, 75 loads and 300 total segments. A maximum of nine levels of voltage is permitted in the system. This project was part of a package of programs developed at Virginia Polytechnic Institute (WI) for the mining industry under sponsorship of the Office of Coal Research. Included in this package are also programs to: 1. Schedule mine production and predict cost of mining 2. Simulate rail haulage systems 3. Simulate belt haulage systems 4. Analyze ventilation networks 5. Analyze pumping networks These programs are available from the Department of Mining Engineering, VPI, Blacksburg, Virginia 24061 for a nominal processing cost.

Jan 1, 1970