Search Documents

By J. Iannicelli

An entirely new level of magnetic filtration technology was put into full commercial production by the kaolin industry of Georgia, U.S.A. during 1973-1974. At present, four kaolin producers in Georgia are operating large magnetic filters each capable of processing over 1000 gallons of kaolin slurry per minute or over 65 tons of kaolin per hour on a dry basis. A fifth large filter will go on stream in August, 1975. Four of these units are 84" machines manufactured by the Pacific Electric Motor Company of Oakland, California. When operated at the maximum 1000 g, p. m. rate, these five large magnetic filters have a combined capacity approximating the entire waterwashed coating and filler kaolin produced in the U.S.

Jan 1, 1976

By R. J. Sweigard

Many states are considering the need to establish or modify policy relating to the disposal of coal ash. One of the primary concerns is the impact of leachate from the ash disposal sites upon groundwater and nearby bodies of surface water. A detailed site investigation was conducted at a coal ash disposal facility associated with a power generation station. The disposal site is situated alongside a major river. Monitoring wells were installed and soil samples were taken for characterization. Groundwater models were used to simulate migration of leachate from the disposal site toward the river. Such models could be used potentially to verify regulatory compliance. This paper addresses the validation and adaptability of these models to this case and their usefulness as possible tools to be used in future environmental audits.

Jan 1, 1992

"Foreword by Emily SarverAssistant professor, Mining and Minerals Engineering, Virginia Tech, Blacksburg, VAThe Mineral Processing Division hosted its fifth Student Poster Contest during the 2014 SME Annual Meeting and Exhibit in Salt Lake City, UT – and, by all accounts, it was a huge success! This year, the contest more than doubled in numbers of individual entries and schools represented. A total of 30 students participated, including 23 graduates and 7 undergraduates, representing 13 US and international institutions: Colorado School of Mines, Michigan Tech, Missouri University of Science and Technology, Montana Tech, New Mexico Tech, South Dakota School of Mines, University of Kentucky, University of Utah, Virginia Tech, West Virginia University, Autonomous University of Chihuahua (Mexico), UNAL Medellin (Colombia), University of British Columbia (Canada). In addition to constructing their posters, students submitted abstracts and gave short oral presentations highlighting their research. Based on tallied scores from all three components of the contest, the judging panel selected 1st, 2nd and 3rd place winners at the undergraduate and graduate levels, which were announced during the MPD Luncheon on February 26.In the undergraduate division, University of Utah’s Lucas Pich was awarded the 1st place prize for his poster “Solid-liquid mixing studies in lab-scale flotation tank using electrical resistance tomography.” His extended abstract is included in this issue of Minerals & Metallurgical Processing. Joshua Chidester, also of Utah, won 2nd place for his poster presenting “Evaluation of detectors for radiotracer RTD measurement by MCNP.” And Lucas Rojas-Mendoza, of UNAL Medellin, took 3rd place for his poster on “Preg-robbing in Colombian gold ores.”In the graduate division, 1st place went to Caelen Anderson, of the Colorado School of Mines, who also placed in this contest in 2012 and 2013! The 2nd and 3rd place prizes were awarded to Jacob McDonald and Joseph Halt, respectively, both of Michigan Tech. Extended abstracts describing the work of these up-and-coming researchers are also included in this issue.The 2014 Contest was chaired by Emily Sarver (Virginia Tech) and Lisa Schlink (Freeport-McMoran Copper and Gold, Inc.). Aaron Noble (West Virginia University), David Perkins (Derrick Corporation) and Derek Novotny (Eriez) graciously served on the judging panel this year.Special thanks are extended to all sponsors of the 2014 MPD Student Poster Contest, and to all student participants. Please watch for upcoming details on the 2015 Contest. We look forward to seeing you in Denver!"

Jan 1, 2015

By D. Meadows, P. Carrato, E. Wingate, K. Churchill

Extracting lunar ice, to be processed into pure water or hydrolyzed into oxygen and hydrogen, faces many challenges. On the Moon icy-regolith deposits that contain up to 10% water are found within Permanently Shadowed Regions (PSR) at both lunar poles, where temperatures approach -220 ⁰C. NASA has identified several technology gaps that exist in developing these resources including: • Excavating large quantities of icy-regolith • Delivering large quantities of acquired resources • Hardware that is lightweight and energy efficient • Hardware that is reliable and durable. NASA uses public challenges to incentivize innovative approaches to closing these gaps. The Break the Ice Lunar Challenge provides over three million dollars in prize money to teams that compete in developing solution to mining the Moon. This paper describes the rules for this challenge and presents some of the proposed solution.

Feb 1, 2023

By Furuyama Takashi, Mori Sukeyuki, Hara Tsuyoshi, Fukushima Yujin

In mineral processing practice, flocculation is largely established as an engineering technique of waste water treatment and the study of parameters increasing the settling velocity of particles is still of great importance to improve the process. Further investigations were made using quartz (Q89) and fluorite samples (F91) which included 58.8% and 65.8% of -2.3 µm particles respectively. In all the experiments the flocculation phenomena were observed varying the pH value of the aqueous suspension. In contrast to quartz particles (Q89) which did not flocculate for all pH values, it was, noticed that fluorite particles (F91) flocculated in the alkaline range of pH over 11. With an aqueous suspension containing equal quantities of Q89 and F91, a hetero-flocculation of particles was observed at a range of pH below 10. In this case, the maximum floc size of the hetero-flocculation was 37.0-26.2 µm This size was about three times larger than when quartz (Q84) and fluorite particles (F85) were used with 32.4% and 40.4% of -2.31 µm particles respectively. Besides, in the experiments using Q89 and F91, the maximum size of hetero-flocculated single particles was found to be 6.54 µm instead of 3.27 µm as obtained with Q84 and F85.

Jan 1, 1995

The declining grades of surface deposits have re-confirmed the need for greater production rates. Large scale production requires increased investments in expensive and sophisticated equipment. The key to successful operations can depend entirely on proper equipment utilisation and in this program of research at the Department of Mining and Metallurgical Engineering, University of Queensland, much emphasis has been placed on the analysis and improvement of this aspect of a load-haul-dump operation. For a model to be successfully integrated into a mine engineering function and readily accepted by mine operating personnel, it has to offer more than just results. The concepts used in its design and construction must include sufficient detail to enable engineers to apply it usefully and with confidence.

Jan 1, 1979

By Paul E. Rosten

This paper describes some of the latest improvements that have been incorporated or planned by the Cleveland-Cliffs Iron Company to reduce operating costs and improve pellet quality. The Cleveland-Cliffs Iron Company operates and manages mining, beneficiation, and pelletizing operations in Michigan, Canada, and Western Australia. This paper deals with the grate-kiln pelletizing operations at Republic, Humboldt, Tilden, Empire, and Pioneer in Michigan, and the Adams and Sherman in Ontario, Canada. Table I characterizes .each operation in regard to location, ore type, pellet capacity and date that pellets were first produced. All of the operations with the exception of Pioneer and Tilden, utilize downdraft-two-pass grate cycles of drying followed by preheating. Pioneer utilizes an all-downdraft, three-pass grate cycle which consists of three drying zones followed by the preheat zone. The Pioneer and Tilden cycles have been described previously. (1) (2)(3) Tilden utilizes a three-pass grate cycle with a stage of updraft drying, followed by two downdraft drying stages. Recuperation systems which supply hot gases to a drying zone from second stage cooling were designed and furnished for Tilden I. Tilden II will be identical. Empire IV will also be furnished with a recuperation system. The Adams grate-kiln system was retrofitted with a recuperation system. This paper will summarize some of the efforts that are in effect or planned for grate-kiln pelletizing systems to (1) reduce operating and maintenance costs, (2) reduce energy requirements, (3) improve product quality, and (4) meet environmental standards.

Jan 1, 1977

By Matthew Preedy, Anthony Pooley, Mike Wongkaew, Dirk Bakker, Raghu Bhargava

Sound Transit’s ST3 program will add 62 miles of light rail to the Puget Sound area, including connections to the neighborhoods of West Seattle and Ballard. These connections include considerations for both elevated and tunnel alternatives in West Seattle and Ballard, as well as a new tunnel and six underground stations in the densely developed downtown Seattle. This paper describes the conditions and constraints along the corridor, and the latest development in the ongoing process to plan the underground guideways and stations.

Jun 13, 2023

By Terrence J. Stobbe

On the job injuries to the musculoskeletal system are probably the oldest of the industrial safety problems. Long before we had pinchpoints to guard, chemical vapors to ventilate, and noise to enclose, people were getting strains, sprains, and sore backs from their work activities. In spite of the age of the problem, it remains a long way from being solved. The past ten years have seen a significant commitment by the sci¬entific community to understanding the problem. Engineers, scientists, doctors, and epidemi¬ologists have been involved, and as a result, today we have a much better understanding of the problem. The first step in understanding a problem such as this is to explore its history and epidemiology. The research done by Chaffin (1977), Snook (1970), Ayoub (1978), the ILO (1962), and others, led NIOSH to publish its Work Practices Guide for Manual Lifting in 1981. The guide was based on research carried out in general industry, but subsequent research by Stobbe (1983) and Peters (1983) has suggested that the nature of the problems producing injuries in underground mining is the same as in general industry. The problems are more intense in the mining environment.

Jan 1, 1984

By Jim V. Rouse

Adverse water-quality impacts of uranium mining and milling activities on both surface- and ground-water resources in the Grants Mineral Belt have recently been documented.1 In some cases, the impacts resulted in violation of existing regulations and license conditions and have endangered public health. Unfortunately, industry-sponsored ground-water monitoring programs do not adequately record the actual impacts of mining and milling on ground-water quality.

Jan 1, 1976

By Feng Liu

"With seven new applications for plans of work for exploration in the international Seabed Area approved by the Council during its twentieth session of the International Seabed Authority, 26 total approvals have been made by the Council up to date. Among them, three contracts were made with COMRA. On 8 August 2014, China Minmetals Corporation submitted another application to the Authority for approval of a plan of work for exploration for polymetallic nodules in the Area, which is also sponsored by the Government of the People’s Republic of China.China is one of the main contributors to the international seabed regime. The Presentation will describe China’s activities in the Area, such as exploration, technology development, environmental protection and policy making.JIAOLONG is a submersible with capacity of 7000 meters. JIAOLONG’s sea trials were carefully made in 4 years, from 2009 through 2012 and it successfully dove to a depth of 7062m in June 2012 at Mariana trench. A so called "Test Application Phase" started thereafter, and is planned to last for 3-4 years. Two cruises and 4 legs have already been made since then. A wide-range of findings were obtained during dives in South China Sea, and in COMRA’s Exploration Contract Areas for polymetallic nodules and cobalt-rich ferromanganese crusts. This presentation will reveal the colorful findings."

Sep 1, 2014

By J. T. Carlson

Dolomite [CaMg(CO3)2] is an intolerable impurity in phosphate ores, due to its MgO content. The need to develop a cost-effective method for the removal of dolomite from high-MgO phosphate ores becomes increasingly important as high-grade reserves become depleted. The jigging process has been investigated as a method for the beneficiation of phosphate ores. A laboratory-scale jig was constructed and tested using a semicontinuous, ?through-the-screen? jigging process. Two types of sedimentary phosphate ore were used; a sample from Plant 1 in the 4.00 x 0.85-mm size range, containing 1.55% MgO, and a sample from Plant 2 in the 3.40 x 0.85-mm size range, containing 3.07% MgO. These were tested, using previously optimized jigging parameters, at high and low feed rates. For the Plant 1 phosphate ore, a phosphate concentrate that contained 0.89% MgO was achieved with a bone phosphate of lime (BPL) recovery of 32.0%. For the Plant 2 phosphate ore, a phosphate concentrate that contained 1.38% MgO was achieved, with a BPL recovery of 74.7%. Minimum achievable MgO grades were also determined by analyzing hand-separated phosphate samples.

Feb 1, 2012

By J. C. Irvine

Meramec Mining Company is a joint venture by Bethlehem Steel Corp. and St. Joe Minerals Corp. which mines and pelletizes iron ore at the Pea Ridge Mine. The Pea Ridge property is located near Sullivan, Missouri, about 70 miles southwest of St. Louis. The orebody was delineated in the mid-1950's by St. Joe during a lead exploration program. The first test holes drilled on the Pea Ridge magnetic anomaly revealed the presence of a large magnetite deposit; further drilling in 1956 and 1957 confirmed that the orebody was mineable, Meramec Mining Co. was incorporated in 1957 and shaft sinking began late in the year. Production commenced in April 1964. The orebody is overlain by about 1300 feet of flat-bedded sediments. It is tabular, about 2600 feet long and up to 600 feet thick. It dips about 80° and is of unknown depth. The ore is mainly high grade magnetite with small zones of specular hematite. The wall rock is a Precambrian rhyolite porphyry. The mine was initially started with five major levels on 150 foot intervals. Crosscuts were driven across the orebody on 190 foot centers. Banks of scopes were mined between the crosscuts by a modified shrinkage stoping method. This was done by undercutting a 40 foot wide by 150 foot long block and blasting horizontal "lifts" drilled on 5 foot intervals. A 65 foot still was left between levels which contained the slushing drift, fingers, crown pillar, and adequate thickness for support. By 1971 a ?lattice? of pillars had been left and mining had progressed to the point that an orderly pillar recovery program was necessary.

Jan 1, 1976

By P. Roghanchi

The difficulties associated with performing direct tensile strength test lead to development of indirect test methods, which are simple, less expensive, and less time consuming. Splitting tensile strength test (Brazilian test) is performed by applying two opposite concentrated compression load across the diameter of a disk specimen until the failure occurs along the loaded diameter. Theoretically, the load is applied over a small width as a line load, however, by increasing the load, the contact width between the loading jaw and the specimen increases as the specimen deforms. The main aim of this study is to investigate the stress distribution in (1) regular Brazilian specimen in traditional tests with loading jaws and (2) flattened Brazilian specimen with flat platens. A series of the splitting tensile strength tests and uniaxial compression strength tests are performed on three rock types: rhyolite, basalt, and limestone. Further, Numerical modeling studies are performed to investigate the effect of the contact between jaw and Brazilian specimen on stress distribution in the disc specimen based on the results from the experimentation. Finally, the stress distribution in the traditional Brazilian test specimen and the flattened end Brazilian test specimen were compared.

Feb 23, 2014

By W. A. Hockings

This report describes a computer program for the solution of material balances in complex mineral processing flowsheets. The program, which is entitled MBS Metallurgical Balance System), evolved as the culmination of a series of material balance programs whose development began in 1967 at the Institute of Mineral Research, Michigan Technological University. The need for such a program became evident when the Institute became heavily involved in a large number of short-term pilot plant projects. Calculating material flows from analytical data by means of the standard two-product formulas grew increasingly difficult and time-consuming as the complexity of the flowsheets increased and as choices between conflicting analytical values had to be made. It was recognized that what was needed was a program that would assimilate all of the available data and calculate mass flow rates so that steady-state inputs and outputs would balance at each point in the flowsheet. Such a program should be capable of handling underdetermined, overdetermined and mixed systems, and when the given data are inconsistent, the program should adjust the data in such a manner that the adjustments are minimized. Missing analyses should also be calculated whenever possible. In addition to solving material balances, the program should be convenient to use and print out the results in a useful form. Thus, the inputting of data should be simple enough to be handled by relatively untrained personnel with diagnostic messages being printed out to identify errors and anamolous data when they occur. Most importantly, the program should produce well-formatted output which can be directly included into a report without the necessity of retyping. The proper spacing of table titles, column headings and the ability to control the columns being printed are important features in this respect.

Jan 1, 1977

By C. Nesbit, N. Duru

During the cyanide leaching process of gold and silver, ores that come from the transition zones which typically con-tains low levels of sulfide may produce one or more of the following reduced sulfur species: sulfide (HS ), polysulfides (Sn ), thiocyanate (SCN ), thiosulfate (S2O3 ), trithionate (S3O6 ), tetrathionate (S4O6 ), pentathionate (S5O6 ) and hexathionate (S6O6 ). The actual speciation of the reduced sulfur species in the circuits will primarily depend on the re-dox potential, pH, cyanide levels and existing sulfur species in recycled process water, as well as the presence of other reac-tive metal species. Development of an accurate analytical method for sul-fur species in cyanide leaching units of gold ores where sul-fur speciation occurs has an important role in explaining the metal recovery deviations. This study presents the speciation of sulfur species and development of an ion chromatography method to analyze the reduced sulfur species thiocyanate, thio-sulfate, trithionate and tetrathionate in cyanide leaching circuits for gold ores. The method developed has resulted in the precise quantification of target sulfur species in leach solutions.

Jun 1, 2024

By Dennis P. Bryan

Nevada is especially well endowed with industrial minerals, both in the number of ore deposits and the diversity of commodities. More than 600 significant industrial mineral deposits, containing 22 principal commodities, are present, in the State. The materials produced in Nevada in 1978 had a value of approximately 113 million dollars, and additional processing of some of them (e.g. gypsum into wallboard, limestone and clay into cement) added considerable more value. Table 1 shows the value of Nevada's industrial mineral production in 1978. Nevada currently supplies 85 percent of the country's barite producing 1.6 million tonnes (1.8 million short tons) valued at 30 million dollars in 1978. Nevada is second in diatomite production and contributes one-third of total lithium produced. Other industrial minerals being produced include clays, fluorspar, gypsum, lightweight aggregates, limestone and dolomite, magnesite and brucite, perlite, salt, sand and gravel, and silica. In general, Nevada produces high-value industrial minerals which are not consumed within the State, but rather, are shipped out of State. In contrast, most more populous states produce larger tonnages of lower value industrial minerals which are consumed chiefly within that state.

Jan 1, 1980

By E. Bloomstein

The Lone Tree gold mine is located about 4S kilometers east from Winnemucca on the west flank of Lone Tree Hill in Humboldt County, Nevada. The deposit occurs at the north end of the low, rolling Havallah Hills and is about 1 kilometer south of Interstate Highway 80, in sections 11 and 14, Township 34 North, Range 42 East, Mount Diablo Base and Meridian (Fig. 1). The Lone Tree deposit is outside of any previously established mining district and all lands are owned or controlled by Santa Fe Pacific Gold or affiliated companies.

Jan 1, 1993

By Robert E. Barrett

The history of mine safety legislation in this country is also a history of mine explosions. Nearly every piece of safety legislation that has been introduced or amended has resulted from some type of a disaster. When coal was first discovered and mined, it was extracted from along outcrops. As the coal became depleted near the surface, underground mining developed. When the first mine penetrated the outcrop, a great number of problems developed, many of which remain with us today. One of those problems is the potential for mine ignitions and explosions. Naturally, when underground mining progressed a few feet into the outcrop, some type of artificial light was needed. Early accounts of mining in Spain, Italy, Japan, and Great Britain indicate that torches served to light the mines. Later, candles were used, and still later, earthern oil lamps containing fish oil were used. As workings got deeper, explosions began to occur. When one did occur it was thought to be the work of goblins or the devil. As explosions became more frequent, it became very obvious that the use of open flames for lighting was very dangerous. A substitute was sought. Dried fish skins which gave off a weak phosphorescent light were tried. A mixture of flour and lime made from oyster shells called Canton phosphorous was also tried unsuccessfully. Fireflies in a bottle were also used.

Jan 1, 1976

Direct force measurements were conducted using an atomic force microscope (AFM) to study the mechanism of copper-activation of sphalerite. The force measurements were conducted between a sphalerite plate and a hydrophobic glass sphere in xanthate solutions of various pHs. The glass sphere may represent the hydrophobic air bubbles interacting with minerals during flotation. The force measurements conducted with unactivated sphalerite in 10') M KEX solutions did not show the presence of hydrophobic force. On the other hand, the results obtained with copper-activated sphalerite at pH 9.2 and 4.6 showed strong hydrophobic forces. However, the results obtained at pH 6.8 showed no evidence of hydrophobic force, which provides an explanation for the difficulty in floating sphalerite at neutral pH.

Jan 1, 1998