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By Aixiang Wu, Minjie Zhang, Zhuen Ruan, Yiming Wang

 The paper combines theoretical and experimental analysis to improve the accuracy of predicting paste yield stress by slump flow. It derives an analytical model of slump flow for yield stress, providing a theoretical basis for quantifying the rheological properties of paste with slump flow. The study uses three different tailings-prepared pastes and constructs an empirical yield stress model, showing high accuracy and good generality.

Aug 1, 2023

There are many risks associated with the storage of nuclear or other toxic wastes. One of the major risks is the escape of material from the repository. No matter how well a storage facility is engineered, the potential escape of dangerous material must be studied. This kind of study will include some estimation of the "travel path" of the particles. The travel path of a radio-nuclide particle will depend on the geological and hydrological parameters of the surrounding rocks. These parameters must be estimated from a limited number of samples available within the study area. Any estimation will -of necessity -contain a certain amount of uncertainty or "estimation error". This uncertainty will be carried through to the analysis of potential movement of particles, so that the estimated travel path itself will be subject to some error. This paper discusses an approach which may lead to a quantification of the uncertainty on the predicted travel path.

Jan 1, 1989

By Mohamed Gamal, Bill Zietlow

"In oil fields that have been depleted with conventional surface oil wells but still contain significant reserves, an extraction alternative that has been constructed recently consists of a drilling gallery below the oil-bearing formation at the bottom of a 1,200-ft deep shaft where upward sloping wells are being drilled to allow oil collection by gravity. The gallery is 92-ft diameter with a flat ceiling supported by rock bolts and shotcrete structurally connected to the shaft liner, which doubles as a large tension support element. A special excavation sequence was implemented for the gallery to maximize arching in the stress above the large diameter gallery. The gallery was located in competent sandstone, constructed with sequential excavation methods, and designed with a 3D finite element model. Special consideration was given to optimizing the gallery location to take advantage of the geology for construction and support while giving good positioning to the well drilling equipment. BACKGROUND Brierley Associates was contracted to provide both design and construction management services for an approximately 1,165-ft deep, 18-ft excavated diameter vertical shaft that opens to a 92-ft diameter flat roof gallery. The geotechnical data for the site was based on information available from literature and from data obtained during core drilling and from in-situ testing in a 1250-ft deep borehole. Wire line coring was conducted using a HQ, 10-ft long core barrel with a mud-rotary drilling method through sedimentary bedrock. The geometry of the shaft and the bottom gallery is shown in Figure 1(a). GEOLOGIC SETTING AND STRUCTURAL GEOLOGY The stratigraphy at the site includes a series of interbedded marine limestone, shale, claystone, siltstone, sandstone, and chert units. Limestone and shale are the predominant lithologies in the upper approximately 675 ft, while the lower portion contains five distinct sandstone units and more abundant shale, claystone, siltstone, and coal than the upper zone. A cherty sandstone at a depth of 1,130 below ground surface (bgs) was encountered. At a depth of about 1,000 ft to 1,116 ft bgs, a non-marine sandstone unit was encountered. This sandstone is the hydrocarbon bearing layer. Joints and fractures observed in the limestone had dips ranging from 0 to 90 deg. from horizontal with joint and fracture surfaces that ranged from planar to irregular and smooth to rough. Several, near vertical shear planes with slickensides were observed with surfaces that were generally smooth and planar. RQD values for the limestone ranged from 0 to 100 percent but in general were good to excellent."

Jan 1, 2016

By H. M. Woodrooffe

In the U.S.S.R. three of the world's major-known phosphate deposits are located. These have an estimated reserve of 2,600 million short tons of contained phosphorus. The best known lies in the "Khibiny Massif', an alkalaic rock formation some 600 square miles in area with mountain peaks rising to an altitude of 3300 ft above the surrounding terrain. Location and Climate The Khibiny Massif lies north of the Arctic Circle in the Kola Penin-sula, 100 miles south southeast of Murmansk, at a latitude of 67° 30' north and a longitude of 35° 30' east. It is serviced by rail from Murmansk and Leningrad (900 rail miles south). Figure 1. The phosphate operations are centered about the two cities of Apatity and Kirovsk. The former has a population of 35,000 and is on the Leningrad¬Murmansk railway. Kirovsk, 15 miles to the east, is now a city of 85,000. The region is at the limit of the tree line with most of the ground cover typical tundra. The mean annual temperature is -4°C and, in a normal year, precipitation occurs on 240 days. Because the temperature does not exceed freezing for 300 days each year, virtually all of the precipitation is snow. The two towns are nestled between mountains and, because of the weather, extensive avalanche control systems incorporating major engineering construction have been introduced to divert snow slides away from the populated areas. General Kirovsk was first settled in 1923 and the apatite occurrences were recognized shortly after. In 1933, the first concentrator for the recovery of the mineral was completed, producing in its first year of operation 170,000 tons of concentrate. With the growth and demand for phosphate in the U.S.S.R., a second concentrator was erected at Apatity. It calve on stream in 1963. Because of the severe climate, in the early days mining was limited to 85 days per year. With the introduction of new techniques and improved mining methods, the season has been extended to 115 days.

Jan 1, 1972

By Ralph E. Weeks

Utilization of true in situ technologies for mining copper in Arizona will involve a complex environmental permitting process. This process is a key factor in determining the feasibility, costs, and implementing time frames required for development of this innovative mining method. The regulatory structure in Arizona is presently changing due to enactment of the Environmental Quality Act (EQA) of 1986 and development of new aquifer protection rules and regulations. The Bureau of Mines has reviewed the comprehensive hydrogeologic characterization, ground water monitoring, mechanical integrity testing, well construction, contingency planning, and other regulatory elements that will serve as mechanisms to assure protection of ground water resources. The purpose of this paper is to inform the domestic copper industry of the significance of the new Arizona regulatory structure and its implications for prospective in situ operators.

Jan 1, 1988

By W. M. Houston

Pebble phosphate deposits of Florida have been established from south of Hardee County to north of the Georgia state line or a distance of over 200 miles and mining has been carried out in an ever-increasing scale since 1885. Deposits that can be mined on the economical standards of today, however, are confined in a roughly circular area about 30 miles in diameter, generally within Polk and Hillsborough Counties, in the central part of the State. The phosphate deposit, which is in the Bone Valley formation of the Pliocene age, is covered by Pleistocene terrace deposits of unconsolidated quartz sand. The matrix is composed of approximately 1/3 clay slimes, 1/3 silica sand and 1/3 phosphate pebbles. The phosphate occurs usually as rounded pebbles, ranging in size from about 1 inch down to approximately 400 mesh. The phosphate may vary from well- defined hard pebbles to soft weathered rock. The color and character of the phosphate will range from smooth buff pebbles to black and white or "salt and pepper rock." The screen size distribution varies considerably between locations and the recoverable phosphate varies may extend down to the 400 mesh size in some areas, while in others the phosphate may cut off sharply at about 35 mesh.

Jan 1, 1962

By Paul H. Miller

After passage by the Congress, Public Law 95-87, the "Surface Mining Control and Reclamation Act of 1977" was signed by President Carter on August 3, 1977. This law, in its simplest form, was intended to control the environmental effects of surface coal mining and to ensure that mined land is restored to a condition equivalent to that prior to mining. Immediately after the signing, the wheels of government bureaucracy began turning to establish a new federal agency -the Office of Surface Mining Reclamation and Enforcement or OSM -in the Interior Department that would implement the provisions of the Act. Since this took time and because the Congress had not yet provided funding for OSM, a special task force was assembled within the Interior Department to begin the task of writing interim regulations to implement the Act. With respect to the use of explosives, the Act specified that a blasting plan be included in the application for a mining permit. The blasting plan will outline the procedures an operator will use to meet specified environmental protection performance standards. The performance standards established by the Act require explosives to be used only in accordance with existing state and federal laws and regulations and with regulations to be promulgated by the regulatory authority. The regulatory authority was defined as either a state agency operating under an approved state program or the OSM operating under a federal program. As a minimum, it was specified that the regulations should include provisions to require that: 1) a blasting schedule be published in a local newspaper and be mailed to local governments and to all residents living within 1/2 mile of the blasting site . 2) daily notice be given to residents in the area prior to blasting. 3) blast reports be prepared that are maintained for three years and available on request to the public. 4) blasts be designed to prevent injury to persons, damage to property outside the permit area, adverse impacts on underground mines and adverse effects on ground or surface water channels or availability outside the permit area. 5) upon request of residents or property owners within 1/2 mile of the permit area, preblast surveys shall

Jan 1, 1978

By W. Hu

Gravity concentration has been the main method for tin ore beneficiation, based on the significant difference of density between cassiterite and gangue in the tin ore. However, with the exhaustion of rich and coarse reserves, the proportion of tin distribution in slime be-comes as high as 50 to 70% and has a size range of -19 urn. In some sulfide tin ore, most of the tin is of the minus 10-urn size fraction, and thus slime processing has gained importance in tin ore processing. Some innovations are being developed, such as the centrifugal cone separator, belt concentrator, slime table, B-M separator, and slime flotation. Direct flotation with tolyl arsonic acid has been practiced with success.

Jan 1, 1989

By R. Chandramohan, Landon Jackson, C. Meinke

Understanding constraints within the raw battery material supply chain is essential for making informed decisions that will ensure the battery industry’s future success. The primary limiting factor for long-term mass production of batteries is mineral extraction constraints. These constraints are highlighted in a first fill analysis which showed significant risks if lithium-ion batteries are used to fully support vehicle electrification and intermittent energy storage. Nickel, lithium, cobalt and graphite reserves risk 100 percent depletion with significant consumption of known resources. Furthermore, more than 700 new critical mineral mines will need to be developed to meet the required production rates for decarbonization by 2050. Demand for critical minerals will outpace mine development timelines even as improvements are made to battery energy density and compositions. Governments and the private sector need to align themselves on decarbonization goals to establish cooperative agreements on the critical mineral supply chain by reducing the barriers to entry and increasing exploration efforts. Additional measures must also be taken to reduce the demand for critical minerals. Policy such as incentivizing public transportation and biking infrastructure can be exploited to drastically reduce the mineral demand placed on the mining industry.

Feb 1, 2025

By J. Lizak

Calcium carbonate is one of the highest volume industrial mineral products in North America. It is used in filler and extender applications, roofing products, floor tile, glass manufacture, etc. Calcium carbonate has over a dozen major filler and extender applications plus a host of minor uses. North American consumption of calcium carbonate fillers and extenders in 1991 is estimated at over 5,000,000 tons valued in excess of $400,000,000. There were five major suppliers of calcium carbonate fillers in the Middle Atlantic region in 1988 :?Bestone, Genstar, National Gypsum, Thomasville Stone and Lime, and White Pigment. With the exception of Genstar's Maryland operation, all of these operations are within a few miles of York, Pennsylvania. The Millington Group (TMG) purchased the assets of Bestone Corporation in February of 1989. TMG then seized the opportunity to strengthen its business position by acquiring National Gypsum's and White Pigment's Pennsylvania filler businesses in December, 1989 and July, 1990, respectively. By July of 1990 TMG's filler business acquisitions included six quarries and one underground mine, totaling over 1,200 acres and three processing facilities. The assets were restructured into two new companies - Delta Carbonate, Inc. and Penroc, Inc. (hereafter collectively referred to as Delta). Delta identified the assets of the three predecessor companies as undervalued from the outset. The initial phase of Delta's turnaround strategy was to reassess the combined mineral. mining, processing, transportation and marketing assets. The second phase was to effectively integrate these resources in order to exploit their inherent synergy.

Jan 1, 1992

By John R. Bogert

The title of this session is "Wall Street Looks at the Mining Industry," and I am going to attempt to answer the question: Shouldn't Mining Stocks Sell at Higher Price Levels? Or, What Does Wall Street See When Looking at the Mining Industry? Well, it sees a capital intensive business, a technical industry, and a growing industry becoming more vertically integrated. But, at the same time, Wall Street sees a cyclical industry, a fragmented industry of erratic earnings, spotty public relations, a feast-or-famine business where the public usually does not differentiate between coal mining or metal mining, and does not appreciate either the risks or the rewards. As a result, mining stocks generally sell at relatively low price learnings ratios in comparison to other industrial groups. This PIE ratio, the current market price of the capital stock divided by annual earnings per share, is probably the most popular index of a stock's value. The average of the price/ earnings ratios of the 30 stocks comprising the Dow Jones Industrial Average is over 14. This diverse group of stocks is widely regarded as being a cross-section and representative of the industrial companies listed on the New York Stock Exchange. However, in comparison to 14, Asarco and Kennecott shares are currently available for about 8 times annual earnings. Even discounting earnings from South America, the stock of these two companies sells at only 10 times earnings. Of course, Peruvian politics is currently preventing Cerro shares from selling above 6 times earnings, and Chilean politics keeps Anaconda shares at a PIE multiple of 7. However, even in better times, these companies rarely sell above 10 times earnings. American Metal Climax and Newmont sell at only 11 times earnings as does Phelps Dodge and St. Joseph Lead. Few mining companies then have what can be considered a high PIE ratio-a figure higher than

Jan 1, 1970

By S. D. Bearden

The world's reserve base is adequate for at least 100 years at the current consumption rate. China, India, and the U.S. are expected to remain the leading producing countries. The U.S. will continue to be the largest consumer of the production. None of the known substitutes for barium sulfate are expected to impact existing applications. World production in 1995 was 4,410Mt. This is about 50% of the projected capacity. Consumption is directly proportional to hydro-carbon well installation activity. Imports are expected to continue to supply more than half of the U.S. requirements.

Jan 1, 1997

By R. K. Will

Granite Construction Company operates a rock quarry in the rugged Santa Cruz Mountains of central California indicated in Figure 1. Open pit methods are used to mine decomposed granite which is processed to produce sand, gravel, decorative rock and asphalt. The quarry is located near the village of Felton about five miles inland from the coast of the Pacific Ocean, and is near the campus of the University of California at Santa Cruz and several California State Parks. The area is heavily forested and is considered by residents to be environmentally sensitive. Because of the scenic beauty of the area and proximity to the San Francisco Bay area, a project such as a quarry receives the attention of regional residents and environmental organizations.

Jan 1, 1994

By N. T. Rogers

An accepted statement of fact is that transportation next to agriculture is the second most important industry in the world. The transportation networks of the United States contributed immensely to the growth and prosperity of our nation. My objective is to make each and everyone here aware of the need for communication between geologists, mining engineers, purchasing agents and transportation managers. Only through a cooperative effort is it possible to reap the benefits of transportation in the industrial minerals field. Transportation is often thought of in terms of trucks, rail cars, barges, covered wagons or whatever. If this is your only exposure to the transportation industry then you probably spent most of your life in a cave.

Jan 1, 1989

By E. E. Malouf

For centuries small amounts of copper have been recovered from acid mine-drainage waters. In recent years, the expansion of copper-bearing waste dump leaching for copper recovery has established a technological basis that is rapidly converting the art of copper leaching' into a science. Leaching of copper, whether from copper-bearing ore or waste, follows well established chemical reactions. These reactions are commonly in an acid circuit, but where leaching of copper is to be made in rock that is a high acid consumer, ammonia and ammonia carbonate, as well as cyanide leach solutions, can be used effectively. Current hydrometallurgical processes are being applied at an ever increasing rate to recover the trace amounts of copper in copper mine waste by in-place leaching. Currently approximately 300, 000 tons of copper are produced annually in this manner where as recently as ten years ago, only one-eighth of this amount of precipitate copper was produced.. Where copper occurs as an oxide in higher concentrations as to be classified as an ore rather than waste, then the hydro-metallurgical processes are applied as percolation or agitation leaching in vats, pachuca tanks, or prepared heaps. This approach gives better control over the recovery of the leach solutions, particularly in the processes where ammonia or cyanide leaching agents are to be used.

Jan 1, 1972

By Ebelia Manda, Peter RK Chileshe, Sydney Chinyanta, Abdul Samson, Victor Mwango Bowa

Buttressing is a widely employed control measure for mitigating slope failure in various settings such as openpit mines, road sections, dams, and hilly or rocky terrains. This paper presents a study on the effects of buttressing, specifically concerning slide-head toppling failure. Drawing insights from a case study of slide-head toppling in Zambia, our investigation employs both analytical (limit equilibrium) and numerical (3DEC software) modeling techniques. The analytical and numerical models exhibit notable similarities in their schematics and overall results, revealing a subtle effect of buttressing in controlling slide-head toppling failure. This study contributes valuable insights into the nuanced role of buttressing in slope stability, with implications for optimizing buttress design parameters. While the overall findings suggest a modest influence of buttressing on slide-head toppling failure, further discussions delve into the specific implications and potential refinements for practical applications.

Jan 1, 2025

By K. E. Hjelmstad

In the event of fire underground, it is essential that all miners be warned as quickly as possible. With mine air, rapidly depleted of oxygen and contaminated with smoke and toxic fire gases, any delay in the warning signal could have disastrous consequences. Unfortunately, present mine, fire warning systems, such as stench, audible or visual alarms, telephones, and messengers, are often slow, unreliable, and limited in coverage.

Jan 1, 1989

By L. E. Sausa

Measuring the specific gravity of a pulp in concentrating plants is a relative, y simple procedure, but the desired accuracy is often difficult to attain. Many plants use the system of weighing a known volume of the pulp on a scale. In many cases, this method is quite accurate, but obtaining a true sample presents quite a problem. This is especially true when the pulp tends to froth, the solids settle rapidly, or the flow is fast at the point of sampling. There is also the problem of the operator neglecting to take the sample because of duties elsewhere, or, if everything Is apparently running smoothly, he assumes the pulp density is also all right. In 1952, the Pine Creek plant of Union Carbide Nuclear Company began working on a better method for measuring and controlling pulp density. After an extensive investigation of different methods for measuring the specific gravity of moving pulps, the Research Department decided that the bubble tube method appeared to be the simplest and most promising for our applications. It consists of two bubble tubes, of different lengths, submersed in a pulp. Low pressure air is supplied to, the two tubes through sight bubblers to maintain approximately equal volume of air to each bubble tube. The bubble tubes are also connected to a differential manometer, one to each side. Therefore, knowing the vertical distance between the outlets of the bubble tubes, the manometere can be calibrated to measure directly the specific gravity of the pulp. (Figure No. 1 illustrates this model.)

Jan 1, 1960

By Virginia T. McLemore

The Black Hawk district in New Mexico hosts an unusual type of deposit: arsenide five-element veins. These deposits are Ag-Co-Ni-Bi-As-bearing carbonate veins with local concentrations of U, Pb, Zn, Sb, and other elements. They are high-grade silver deposits (1000s g/t Ag), but low tonnage (<1 Mt) and difficult to find. By 1881, claims were staked and a town developed. It is estimated that >$1,500,000 was produced in 1883–1893, when Ag prices dropped due to the 1893 Ag panic. Solid Silver Mining Co. produced $600,000 from the Black Hawk mine; one car load contained $28,000 worth of silver! The town of Black Hawk grew to 125 population by November 1883. By the end of 1893, the town was vacant; nothing remains. The district was idle until 1916, and the mines operated sporadically since because of lack of available capital, water issues, and difficulty in finding ore shoots. The area is a favorite for mineral collectors. Tungsten was found in the district in 1935 in quartz veins associated with pegmatites. Metal production from 1881–1960 is estimated as 3,000 lbs Cu, 1,000 oz Au, 1,286,000 oz Ag, and 4,000 lbs Pb. In addition, 10,542 short tons of 2.7–71% WO ore and 615 short tons of fluorspar ore have been produced from the district.

Feb 1, 2025

By Alvaro Veizaga, Samuel Cuellar

In recent years, Industry 4.0 has generated a change in the way companies in various industrial sectors design, produce and deliver products and services, and is focused on the interconnection of systems, the advanced access and management of large amounts of data in real time, and the implementation of emerging technologies such as the Internet of Things (IoT). Artificial intelligence (AI), machine learning (ML), digital twins (DT), robotics, virtual and augmented reality (VR/AR), among others [1]. DTs are accurate and dynamic virtual models that replicate physical systems, where it is possible to simulate and optimize operations before implementing real-world changes [3]. These features make it possible to reduce investment costs, minimize risks and improve strategic decision-making. These benefits are of utmost importance for tailings storage facilities (TSF), since they are facilities aimed at the safe storage of tailings and with the constant need for growth [4]. This paper evaluates the applicability of a DT in a TSF from a conceptual perspective, providing the advantages of its implementation, but also the barriers identified in the industry based on the authors’ experience.

Feb 1, 2025