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By Fangyu Liu

In the grand tapestry of scientific inquiry, there are individuals whose contributions resonate far beyond the confines of laboratories and lecture halls. It is with profound admiration and respect that we present this special collection of Mining, Metallurgy & Exploration, dedicated to celebrating the remarkable career of Dr. Patrick Taylor. Dr. Taylor, recently retired from the Colorado School of Mines as the Emeritus Ansell Distinguished Professor of Chemical Engineering, possesses over 45 years of expertise in mineral processing and extractive metallurgy. His remarkable journey has seen him traversing the globe, from Canada to Egypt, contributing to pyrometallurgy, hydrometallurgy, and mineral processing. Dr. Taylor’s portfolio encompasses lab work, pilot-plant projects, research, and process development across various metals, with an impressive array of authored papers, presentations, and nine patents to his name. A soughtafter consultant for over 20 companies and an esteemed expert witness, Dr. Taylor also led the Kroll Institute for Extractive Metallurgy at Colorado School of Mines. Under his guidance, more than 100 graduate students and post-docs have undertaken transformative research, while Dr. Taylor’s 45-year tenure as a university lecturer and the creation of 10 industryfocused short courses underscore his dedication to knowledge dissemination. His contributions extend to crafting professional engineering exam questions for a quarter-century and active participation in esteemed organizations like SME, TMS, ASM, and MMSA.

Sep 16, 2023

By D. L. Langhans

Platinum-group metal (PGM) converter matte from the Stillwater Complex, MT, was subjected to chemical and biological leaching in an effort to upgrade the matte by decreasing the Cu and Ni content. Copper and NL extractions were optimized in a two-stage chemical leach. Atmospheric pressure sulfuric acid leaching removed over 90 pct of the Ni and Fe in the first stage, while 95 to 98 pct of the Cu was removed is the second stage using an acidified cupric chloride leach. This two-stage leach, followed by an elemental sulfur removal step, decreased the weight of the matte by 90 pct. The combined Cu and Ni content was reduced from 65 pct to less than 20 pct, while the PGM content was increased from less than 2 pct to 26 pct. Biological oxidation using Thiobacillus ferrooxidans also proved to be an effective method for removing Cu and Ni. Over 90 pct of the sulfide was oxidized and 99 pct of the Cu and Ni were solubilized, leading to a 60 pct reduction of sample mass during the 17 week bio-oxidation of the Stillwater converter matte. The final residue, after removal of jarosite that accumulated during bio-oxidation, contained less than 3 pct combined Cu and Ni and 6 pct MM.

Jan 1, 1993

By W. J. Kennedy

Energy management in industry has recently achieved notice as a way to reduce costs without decreasing production. The same approach used in industry can be used in mining, even though the processes are different. This approach is based upon a three phase system of data collection, implementation, and monitoring, all aimed at gathering and evaluating information in such a way as to have a maximum impact on energy costs. This approach has these advantages: (1) attention is directed toward the part of each mining system where the most energy is used, (2) input is collected systematically from all persons involved in the operation of each system, and (3) a means of monitoring the progress toward established goals is created. The mining systems considered are truck haulage, conveyor haulage, blasting and crushing, and lighting. After describing the general procedure, the authors have described a specific method for improving the efficiency (and hence the energy consumption) of round-trip truck haul age systems.

Jan 1, 1982

By Thornton L. Neathery

The low-grade talc deposits in Tallapoosa County, Alabama, are associated with a mafic-ultramafic rock complex that is part of a widely distributed schist and gneiss group. These rocks form a synform structure overlying Inner Piedmont lithology. Paragenetic sequence of the Tallapoosa talc is interpreted as enstatite-anthophyllitetalc. Talc occurs as massive boulders formed by the alteration of enstatite-anthophyllite and as finely disseminated discrete particles in the enclosing saprolite matrix. Weathered rock reaches depths as great as 60 feet. The quality and quantity of the talc, however, are variable. Mineral analyses of the talc-bearing samples, by petrographic grain count, indicate a talc content of 16 to 26 percent. Most of the talc occurs as plates or scales that are moderately stained with limonite. Fibrous talc also occurs in the deposits and is often mistaken for anthophyllite asbestos which is intimately associated with the talc. The size, shape, and occurrence of the talc deposits precludes any method of min¬ing other than open-cut. A small-scale mining operation began in the district in 1969. Potential capacity of the operation is 5, 000 tons per year. Inferred reserves, based on field investigations, are placed at approximately 8 million tons. Approved for publication by the State Geologist, Geological Survey of Alabama.

Jan 1, 1970

By George Vranesh

Synfuels development in the upper Colorado River basin and the population growth attendant with such development demand sizeable quantities of water. Unfortunately, the water supply in the basin is limited and such limitation may impose a significant constraint on the development of the West's abundant energy resources. Although the water for the synfuels development will be governed by the law of prior appropriation adopted in the upper basin states, the authors point out that an apparently senior water right .my not deliver a firm supply of water. The federal and Indian Reserved Water Rights Doctrine, the Colorado River Compacts the Doctrine of Equitable Apportionment, and the federal and state environmental laws can all severely diminish the value of any given water right and the synfuels industry should take care to evaluate these factors in acquiring its water.

Jan 1, 1981

By Yasutaka Izumi, Tuneyoshi Funasaki, Keizou Miki, Makoto Kanai

INTRODUCTION The Tokyo metropolitan region, inclusive of the three neighboring prefectures (Kanagawa, Chiba and Saitama), has the highest concentration of population and industry in Japan; with an area of 13,500 km2 or only 3.6 percent of the national land, but a population of 31.8 million or 26 percent of the national total, and a Gross Regional Product (GRP) of146 trillion yen (US$1.33 trillion) or 36 percent of the overall GDP of Japan as of 1990. Tokyo Bay, embraced by the metropolitan region as shown in Figure 1 (a), (b), is open to the Pacific Ocean as a marine gateway and is ringed by large cities and coastal industrial zones together with port facilities, all constituting a concentration of prime importance for socio-economic activities. The Trans-Tokyo Bay Highway (TTB highway), which crosses Tokyo Bay and provides a direct transportation link between the west and east sides of the bay, has long been a sort of “dream-come-true” project in Japan. As shown in Figure 2, linked to the Tokyo Bay Shore Highway, Metropolitan Inter-city Expressway, Tokyo Outer Ring Road, Tateyama Express-way, and others, it will play an important role as an integral part of the regional highway network to help promote spatial redistribution and multi polarization of urban functions, thus strengthening cooperation between cities and restructuring the metropolitan region. The TTB Highway is a project of 15.1 km in length designed as a toll highway to cross the bay by tunnel and bridge, and will require ten years to complete at a total cost of more than 1,438 billion yen (US$13.077 billion). Following more than 20 years of feasibility and environmental assessment studies, construction of this giant offshore highway project commenced in May 1989 as the first large-scale highway project with private-sector participation under the prevailing Road Law in Japan, and is now steadily proceeding toward the goal of completion in fiscal1997. This report outlines the entire TTB Highway project, including the waterproofing measures against high water pressure and the rapid construction method applied in the construction of shield tunnel sections.

Jan 1, 1997

By N. B. Aughenbaugh

The People's Republic of China has 582 Gt (641 billion tons) of proven coal reserves. At present, 576.5 Mt (635.5 million tons) of coal are mined a year which makes China the third largest producer of coal in the world. Underground mining accounts for 95% of the total production. This paper will discuss the coal districts, coal types, jurisdiction of coal mining, and methods of underground mining. The article also will outline China's objectives in future planning and development of its coal reserves.

Jan 1, 1982

By J. Bickson, C. DeGennaro, J. Homer, M. Girman

Powered haulage and haul truck-related fatal accidents are among the most frequent at surface mines. Industry organizations developed guidance on accident scenarios to address haul truck and mobile equipment collision-related accidents. However, there is a need to investigate accident data to prioritize these scenarios and identify factors relevant to developing validation methods for collision warning/avoidance technologies and determining their capabilities and limitations. Standards and effective validation methods are necessary for improving system efficacy within mining operations and promoting industry adoption. To address these needs, researchers from the National Institute for Occupational Safety and Health (NIOSH) investigated available powered-haulage and machinery-related fatal accident reports documented by the Mine Safety and Health Administration (MSHA). Their objective was to gain a perspective for informing the development of test protocols and validation methods through determining the most prevalent accident scenarios and related factors. Our findings afford insight for addressing the most prevalent haul truck scenarios and relevant factors within U.S. surface mining environments.

Mar 2, 2022

By Yung Sam Kim

The study of ultrasonic-wave propagation in substances has been remarkably advanced in recent years in most engineering and science fields. The main object in studying the velocity of ultrasonic-wave propagation in solids, is to determine dynamic properties of these materials. The present paper, however, presents some other possible applications of ultrasonic-wave propagation in the study of rock mechanics as follows: Investigation of the mechanism of microseismic activites of geologic materials, (a) at initial or low stress level, (b) at final or fracture stress level, and (c) under fatigue loading condition. Also, correlations among stress level, density, and the velocity of ultrasonic-wave propagation in rocks are discussed in this paper.

Jan 1, 1973

By George A. Komadina

Pima Mining Company has recently completed their expansion tripling the plant capacity to 18,000 tons per day and now is in the process off expanding to 30,000 tons per day with completion scheduled for the summer of 1967. This paper briefly discusses the additions to the mining department and support areas with a more detailed report on the complete new crushing plant and additions to the concentrator. The crushing plant includes a 54-inch gyratory crusher, three 7-foot standard and seven 7-foot short head crushers along with necessary screens, feeders, and conveyor belts to produce a minus 1/2-inch rod mill feed. The concentrator consists of ten milling sections, each containing one 10-foot by 16-foot rod and two 10.5-foot by 13-foot ball mills, classification is done with cyclones. Pulp from each section is floated in 50 cells of 66-inch Fagergren flotation machines to produce a rougher concentrate which is cleaned in six stages of Denver cleaners to produce a final concentrate The various mill products are thickened with disposal made in conventional manner. Plant instrumentation is discussed in the paper.

Jan 1, 1967

By Craig J. Nelsen, J. Leroy Schutz

The Carache Canyon Prospect consists of a hypabyssal breccia pipe which intrudes a gently dipping sequence of Cretaceous Mancos Formation and Mesa Verde Group shales and sandstones. This sedimentary sequence is intruded by a number of Oligocene (34-30 Ma) calc- alkaline sills. The formation of the breccia pipe and its subsequent gold mineralization is related to the emplacement of an alkaline intrusive complex dated between 30-26 Ma. An exceptionally large block within the pipe provides compelling evidence that brecciated sills and sedimentary rocks form a relict stratigraphy that collapsed 400-800 ft (120-240 m) below their counterparts outside the pipe without substantial changes in stratigraphic position. Native gold and sulfide mineralization within and around the pipe occurs in fractures that are primarily controlled by competency differences between sills and sedimentary rocks and secondarily controlled by ductility contrasts between the relatively brittle Mancos Formation hornfels and the more ductile Menefee Group shales. The resulting pattern of gold mineralization is a series of stacked, tabular, mineralized sills and sandstone separated by barren shale in an annular region along the southwest margin of the pipe. A series of near-vertical, subparallel, sill and sandstone breccias separated by barren or weakly mineralized shale breccia occur within shallow levels of the pipe.

Jan 1, 1990

By P. Raffinot, C. H. G. Bushell, S. Hodgson, E. F. Milner, H. J. Bosshardt, N. Draper, D. E. Pickett, Edwin T. McKnight, J. Prieto

Zinc ranks third and lead fourth in world nonferrous metal conumption. In 1972 the free world consumed 3,333,000 mt of refined lead and 4,422,000 mt of refined zinc. The lead tonnage was divided into the following end uses: storage batteries (42%), lead allows (7%), pigments and chemicals (11%), cable sheathing (9%), gasoline additives (13%), pipes and sheets (8%), and miscellaneous uses (10%). The corresponding distribution of zinc uses in 1972 was galvanizing (39%), die casting (26%), brass (15%), rolled zinc (8%), oxide excluding American Process zinc made directly from concentrate (6%), and other uses (6%). The pattern of usage of lead and zinc varies considerably from country to country. During 1972 in the USA 49% of refined lead was consumed in storage batteries, 19% in gasoline additives, and only 3% in cable sheathing, whereas in the United Kingdom 28% of the lead was consumed in batteries, 14% in cable sheathing, and 14% in gasoline additives. For zinc the major US uses were die casting (41%) and galvanizing (37%), with about 3% consumed as rolled zinc; corresponding usages in the same applications in France were 12, 28 and 28% and in Australia 12, 67, and 3%, respectively. The outstanding resistance of lead to corrosion, its density, and

Jan 1, 1985

By Richard R. Klimpel

The purpose of this paper is to summarize some of the author's experiences in applying population balance models to a variety of industrial grinding circuits. Over 26 separate industrial circuits have been studied in detail during the last 10 years, each unique in its equipment type and layout as well as in the material (s) being ground. The success of the population balance approach during these studies was variable. Fourteen of the circuits were shown to be very amenable to such an approach while the remainder had conditions present that sufficiently violated the standard population balance assumptions so that the analysis was of less than optimal utility. Some discussion of the importance of standard population balance assumptions will be given. It is increasingly becoming this author's opinion that the use of population balance models has its greatest utility in defining logically and cheaply (in contrast to actual physical testing), the relative limits and comparisons of different proposed circuit configurations and changes in equipment types and/or operating conditions. As far as specific quantitative predictions and actual optimization of existing plant performance, the results of applying the population balance approach have been often disappointing and need to be coupled at the plant level with other engineering quantification techniques in order to achieve desired improvements.

Jan 1, 1992

By D. J. Bryden, J. W. Oberholzer

In response to the need for enhanced precautionary measures to safeguard mine workers in collieries from the consequences of methane ignitions in a heading, the coal mining industry has ex- pressed the desire for the development and testing of active on board suppression systems. As overseas systems cannot be used directly in the bord and pillar geometry it is necessary to adapt overseas and local technology to suit local mining conditions, as well as to test such developed systems for their compliance with the expressed needs. As the systems have to be tested in a specific roadway configuration, a facility was developed to enable the testing in South Africa. A surface test facility has been established which can be used to develop and test suppression systems on continuous miners and roadheaders. This facility consists of a tunnel wherein compliance tests can be conducted in simulated underground conditions. A number of methane explosion tests have been conducted in the test facility. The explosions conducted varied in CH,/air concentration (7,5 to 9 percent) and volume (26 to 88 m3). At lower concentrations there was a marked reduction in explosion strength and flame speed. Tests carried out with the Explostop system successfully suppressed the propagation of methane ignitions in both scenarios tested.

Jan 1, 1997

By Walter Steiner, Claus Becker

INTRODUCTION General Switzerland is a densely populated country in the heart of Europe. With its total surface of 41.300 km2 and a population of 6,8 million in 1986 the average population density is 163 capita / km2. The population density is lower than in Germany (245 capita/ km2) or the Netherlands (355 capita/km2). The USA have a population density of 26 capita/ km 2. However, sixty percent of the Swiss surface is covered by the Alps and another ten percent by the Jura mountains the remaining thirty percent of the surface is covered by the Swiss plateau where the majority of the population lives. The population in the inhabitated areas is thus substantially higher and may possibly reach those in major metropolitain areas. Due to the high population density in Europe in general and Switzerland in particular future traffic demands cannot be fulfilled sole by car or plane. Environmental and land-use constraints lead to the third option for growing transportation needs: High-speed rail (Bovy, 1990). Switzerland has developed its own approach to promote public transportation and in particular rail transportation: "Rail 2000" (Stalder, 1990). The system "Rail 2000" is based on a series of hubs distributed over Switzerland where easy connections can be made.

Jan 1, 1991

By V. A. Kharchenko, V. M. Yeremeev

INITIAL PRECONDITIONS To solve tile problem of using the potential reserves of the different coal ranks efficiently (the coal reserves being many times superior in quantity to those of natural gas and oil) one must realise an integrated estimation of the coalfields' and coal deposits' reserves. The actuality of this problem increased especially in the recent years, when the Russian coal industry is being restructured. A structural reorgaisation of this industry, in order to in- crease its efficiency, covers a large spectrum of social and economic problems, comprising a withdrawal from mining the coal reserves that are unsafe from the standpoint of economy and labour protection. According to the information supplied by the 'Rossoogol' company, the Russian coal industry, accounting for abut a fifth of the world coal reserves, has a rather unsafe resource base, for about 5% of the reserves involved in mining do not correspond to the world practice conditions, regarding the coal grade, thickness, geological conditions, proneness to coal and gas outburst hazards. These concern first of all the Moscow, Kizelovsk and Donetsk coal basins, the Prokopievsk-Kiselevsk district of the Kuzbas basin and several other coalfields. Thus, the problem of efficient potential coal reserves' utilization calls for a paramount solution of two basic problems, namely: a) a comparative coalfields' and sections evaluation, and their ranging, in accordance with their industrial importance; b) choosing the 'active' reserves good to be efficiently mined under the present-day conditions. PRINCIPLES OF EVALUATION The investigations that had been carried out make it possible to formulate the following basic principles of the coalfields' reserves' estimation (or assessment). 1. The necessity, possibility and expediency of coal reserves' industrial exploitation are determined by a set of natural, technical, technological, practical, economic, environmental and social factors, thus calling for an integrated and gradual approach to problem solving. 2. One cannot consider the results of same reserves' estimation as being invariable because the former depend both upon constant (mainly natural) and market demands for different grades of coal (those of different power engineering and technological situations), capital investments, material and labour resources, economic (price-forming), technical, technological, environmental and other factors. 3. The rational size and sequence of the operating mines' and reserve sections' resources' involvement into mining depend upon the final aim of posing the problem, whose variants may be (the corresponding limitations being considered) providing for a maximum run-of-mine output (these essentially featuring the past stages of the industry's evolution); providing for a maximum efficiency, measured possibly by the specific or absolute indices of profits an expenses, labour productivity e. al. ; providing for a maximum extraction (maximum integrate utilization) of the known reserves. In this case an important park goes to the economic evaluation (or assessment) of useful application of the by-products being extracted (methane, mine water, rack) compared to the expenses necessary for their utilization. Regarding the steam coal (posing the problem any way it be possible), and extreme limit to the absolute non-efficiency of the coal reserves' exploitation may be posed, using the proportion of energy obtained from the possible amount of the coal to be extracted to the energy consumption necessary to extract, prepare, haul and consume this amount of coal. 4. The most reliable and efficient solutions providing for opening the reserves can be obtained for group of mines, rather than at the level of an individual mine section or an individual mine because it is only in the former case that the possibilities to re- distribute the expenses necessary to develop the good for mining and worse sections and seams can be realized to the greatest extent. Therefore the prospective approach to be considered is the one providing for an integrated organization and choice of the optimum combination of the variants of the ways to use the mines in operation and the free sections of the region in order to satisfy the growing up requirements for coal rather than the one providing for individual mine sections' resources' evaluation. 5. The future possibility and expediency of coal reserves' industrial exploitation will depend upon the prospects to implant at the mines in operation and reserve sections new engineering and technological elements and coal extraction technologies which may essentially change the actual idea concerning the coal reserves worth of being developed in an efficient way. For example, reserves not available to be exploited using conventional coal extraction technology may be regarded as potential resources for in situ gasification, e. g. the operating mines' reserves (non-commercial and non-mined commercial ones), balance and outside balance reserves of the free sections having proved not available to be mined using conventional coal-extraction technologies, as well as the non-extracted reserves of the abandoned and closed mines.

Jan 1, 1996

By Sidney M. Cohen

[Portland cement is a product made from a combination of limestone and argillaceous material which would supply the necessary amounts f calcium, silica, alumina and iron to form cementious compounds when fired at high temperatures. The resulting mixture, usually around 80% limestone and 20% argillaceous, is ground nine (80% -200 mesh), blended and then fired1 (2600-2700°F) to produce a cement clinker from which the final cement product is produced by grinding. The argillaceous component can be shale, clay, slate or other sources of the individual components of silica, alumina and iron. This paper deals with a case where a clay component was under consideration. The planned Plant site was to be located at a well defined limestone deposit. When it came to the argillaceous component, the nearest uniform deposit of clay was over 50 miles away and would require purchase of land or clay from the owner plus the daily delivery costs to the plant site. This situation made the plant site economically questionable. It was decided that a local clay deposit, which was available at the plant site but was orginally not considered due to lack of chemical uniformity and its high free silica content, would be reconsidered.]

Jan 1, 1983

By William W. Edgerton, Moussa Wone, David H. Corkum, Carlton M. Ray

"The DC Clean Rivers (DCCR) Project is a 25 year, $2.6 Billion court ordered project to reduce combined sewer overflows (CSOs) discharging into the Potomac and Anacostia Rivers and Rock Creek, and also reduce flooding in the northern areas of the District of Columbia. Like all massive infrastructure programs, DCCR faced technical challenges, management challenges, risks of cost and schedule overruns, procurement challenges, and financing challenges. While DC Water is no stranger to large capital improvement projects (CIP), this CSO Program represents a once in a lifetime event for the Owner requiring the assembly of a single purpose team to implement. Some of the DCCR Project team’s most successful accomplishments to date are attributable to its introduction of early contractor involvement (ECI) to thoroughly vet the work from the perspective of the future constructors, development of functional baselines to share risks that are difficult to price and reduce reliance on geotechnical baseline interpretation during tunnel excavation, and attainment of financing through Municipal Century Green Bonds based on using design criteria of a minimum of 100 year life for the structures to establish intergenerational equity and fairness. This paper will discuss these innovations in detail and provide some sets of recommendations for the underground industry on when and how to use different approaches to better manage projects of this magnitude. INTRODUCTION The District of Columbia Water and Sewer Authority (DC Water) is an independent multi-jurisdictional authority that was established in 1996. Its primary mission is to provide water distribution services to more than 640,000 residents in the District of Columbia (District), and sewer treatment and disposal to 1.6 million residents of the District, Montgomery and Prince George’s counties in Maryland and Fairfax and Loudoun counties in Virginia."

Jan 1, 2016

By T. H. Bagan

The Sixteen-to-One Mine was originally designed and operated using Blasthole Stoping with end slicing as the primary mining method. This method changed to Modified VCR Stoping in response to efforts to control dilution. The new method combines Blasthole Stoping with shrinkage methods, pillars, and reduced sublevel intervals to provide the most practical dilution control avail- able for low cost bulk mining.

Jan 1, 1987

By Wayne Hilgedick

Peabody Coal Company is the nation's largest producer of coal and is headquartered in St. Louis, Missouri. In 1978 Peabody divisionalized its operations to establish more responsive and effective mine management. Peabody Coal Company's Arizona Division operates two large surface mines, the Black Mesa and Kayenta Mines. Both are located in northeastern Arizona, approximately 30 miles from Kayenta, Arizona, on the Navajo and Hopi Indian Reservations. The Black Mesa Mine produces 4 to 5 million tons of coal per year and the Kayenta Mine produces 7 to 8 million tons per year. Coal from the Black Mesa Mine is transported 274 miles by coal slurry pipeline to the Mohave Generating Plant located on the Nevada/Arizona border at Bullhead City, Arizona. This plant is jointly owned by Southern California Edison, the Los Angeles Department of Water and Power, Nevada Power Company and Salt River Project Agriculture Improvement and Power District.

Jan 1, 1983