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By Theodore S. Jordan

The discovery of a major porphyry-type copper deposit on the Papago Indian Reservation in Pinal County, Arizona was announced by El Paso Natural Gas Company in 1968. The deposit, known as the Lakeshore Property, contained an estimated 470 million tons of sulfides and oxides averaging 0.75 percent copper. History and Geology of the area have been described by Harper and Reynolds (1969). El Paso subsequently&apos; entered into the agreement for joint development of the property with Hecla Mining Company, with Hecla as the operator. The ore body consisted of three types of mineralization: 1) Disseminated Oxide Ore, <1% Cu 2) Disseminated Sulfide Ore, <1% Cu 3) Tactite Ore, >1% Cu

Jan 1, 1985

By QUANWEN PU, Yonggang Wei, Bo Li

The spent catalyst is one of solid waste resources, which contains precious metals with considerable recovery value. However, due to the different compositions of catalyst, the recovery process is difficult. Most of the catalysts are supported by alumina which has good alkali-soluble properties, while platinum is insoluble in alkali. Platinum is enriched by pressurized alkaline solution which is a kind of hydrometallurgical process. The novelty of this study is the separation of alumina and platinum from the spent catalyst and the enrichment of platinum in the solid phase. In this study, a leaching process using NaOH as leaching agent under high temperature and pressure was employed. The effects of alkali concentration, leaching temperature, leaching time, and liquid–solid ratio on leaching efficiency were investigated. The optimum process conditions were determined as follows: alkali concentration of 240 g/L, temperature of 200℃, pressure of 1.20 MPa, time of 1 h, liquid–solid ratio of 5:1. It was concluded that the leaching rate of alumina can reach 99.69%. The content of platinum increased from 0.1749 to 21.12%, the loss of platinum was 3.39%, and the enrichment ratio of platinum increased by 120.82 times. The leaching kinetics of alumina was studied based on the shrinkage core model. The activation energy of alumina leaching is 19.53 kJ/mol, and the leaching process is controlled by chemical reaction. Pressurized alkali solution can not only efficiently leachate alumina from the spent catalyst and enrich platinum, but also reduce the reaction time and increase reaction rate.

Feb 11, 2022

By Tim O’Neil

Nearly 4,800 mining professionals and exhibitors occupying 580 booths attended the 2000 SME Annual Meeting and Exhibit, Feb. 28-March 1, in Salt Lake City, UT. The technical program included80 sessions and four specialty symposia: bulk material handling, control 2000, minor elements 2000 and plant operaters. Meeting highlights included the keynote session. Executive shared their perspectives on pivotal issues and approaches to address the challenges of the new millennium. SME has begun planning for its 2001 Annual Meeting, Feb. 26-28, in Denver, CO. The meeting carries the theme “2001 — A Mining Odyssey.” A call for papers has been issued and exhibit space is 80% reserved. For information, visit SME’s website, www.sme-net.org. Or write Box 625002, Littleton, CO 80162-5002,ph 800 763 3132 or 303 973 9550, fax 303 979 3461, or email meetings@smenet.org.

Jan 1, 2000

By Georgene Renner

With more than 800 booth spaces sold and 540 exhibiting companies displaying their wares, there was something for everyone on the exhibit floor of the 2014 SME Annual Meeting in Salt Lake City, UT Feb. 23-26. The following is a sample of what was offered at the 2014 meeting.

By C. Hendricks

This paper is based upon field studies conducted in a western Canadian open pit coal mine. This work has involved the adaptation of microprocessor-based instrumentation to monitor various operating parameters on-board blasthole drills and mining shovels. A review of instrumentation and monitoring methodology will first be presented. Based upon experience from field-based studies, the paper will subsequently focus on the application of monitoring technology within the framework of an integrated Equipment Monitoring System. Such a system will permit the real-time performance evaluation of key equipment involved in surface mille production.

Jan 1, 1991

By Tim Arnold

"Justified is a show on FX that takes place in Kentucky coal country. The two main characters, a cop named Raylan and a criminal named Boyd, are adversarial to the very end, yet they manage to maintain a seemingly inexplicable bond of friendship through it all. The final episode ends (spoiler alert) with Boyd asking Raylan why that is. He responds, “If I allow myself to be sentimental, there is one thing I wander back to” Boyd responds, “We dug coal together.” Fade to black.What creates these types of bonds between friends and co-workers in mining? I don’t know about you, but many of my best friends I met in mining. Certainly the people I respect the most in this world are a part of our industry. Good, honest, honorable men and women. And I am not just talking about the leaders of our industry. I am talking about great miners who taught me how to do the right thing and also be productive.I have had the pleasure to work for some great people and the misfortune of working for some of the loudest screamers. What I consider the worst butt-chewing in my life may surprise you. I once worked for a man I respected, because he showed me respect. He went on a business trip and left some instructions. For some reason, I was able to justify to myself that they applied to everybody but me, and I disobeyed them. When he returned he called me into his office and said to me: “Tim, you pissed me off when you did that.” He said it quietly and with no anger. I had lost his respect. This devastated me more than any screaming shift boss ever could have. I learned a lot about values from that conversation.Most of us will spend more time at work than we will with our families over a lifetime. It is natural that tight bonds be created at work. What I believe makes mining special is that these bonds are so strong. They are strengthened by the incredibly hard work our miners do. They work at all hours, on holidays and in all sorts of extreme weather conditions. The physical demands of the job are sometimes exhausting. Our bonds are further reinforced because the work is dangerous. Not only does management watch out for the wellbeing of their people, but each and every one of us looks out for one another. The bonds are made tight because our people are so passionate about what they do, no matter the department or profession. Finally, they are strong because of the thousands in the industry that keep doing the right thing, every day. We make great friends in this industry because of the strength of character of our people. That is why Boyd and Raylan respected one another so much."

Sep 1, 2016

By J. C. Wynn

J.R. Hillebrand From the abstract, "A realistic ore deposition model to serve as a conceptual framework." Further, on page 246, "The first area of study was the Josephine peridotite, now identified as an ophiolite terrane, located in northern California and south-western Oregon (Fig. 3). Here, it was felt that we could test the models shown in Figs. 1 and 2 and, if successful, expand the model and test it in other chromite districts in the US and around the world." My comments refer only to chromite deposits in Europe and the Middle East. First, I question that may chromite deposits occur in the idealized ophiolite section shown in Fig. 1. Second, although some podiform deposits (referring to morphology) have been important (Guleman, Turkey, for example), the stratiform deposits are of greater importance in tonnage and frequently grade. Examples include Nada, Yugoslavia; Bulqiza, Albania; Xerolivado, Greece; Saranovsk, Russia; and Abdasht, Iran. Reply by J.C. Wynn Mr. Hillebrand raises two issues that deserve a serious response. One issue is basically subjective and the other is ultimately political. First, the question of where (and how many) podiform chromite deposits are found in the idealized ophiolite section of Dickey (1975). The Dickey model is still perhaps somewhat controversial (Panayoutou, 1980), but our experience in the Josephine ophiolite of northern California (Wynn, 1980; and Albers, 1983) shows that the model works well there. Virtually all the chromite is found in dunite lenses in the tectonite peridotite (harzburgite). Since there are few complete ophiolites exposed in the world, the model will probably never satisfy everyone. The degree of acceptance is a function of any individual&apos;s subjective experience. Second, it is well known that stratiform chromite contributes more than 95% of the chromite reserves presently known in the world, and it could be reasonably argued that there is no point in exploring for or exploiting podiform deposits further. The title of the paper, however, was in part &apos;strategic minerals geophysical research&apos;; chromite is considered a strategic and critical mineral of the US and many other industrialized nations. Stratiform deposits in South Africa and Zimbabwe account for most of the chromite reserves in the world. Unfortunately, experience in modern times with substantial price fluctuations and even resource cartels dictates the wisdom of identifying and maintaining a national chromite reserve, irrespective of the cost. An improved exploration methodology is an essential element in this strategic objective. References Albers, J.P., 1983, "Geological and Geophysical Studies of Chromite Deposits in the Josephine peridotite, California and Oregon," US Geological Survey Bulletin 1546 A-D, 118 pp. Dickey, J.S. Jr., 1975, "A Hypothesis of Origin for Podiform Chromite Deposits," Geochimica et Cosmochimica Acta, Vol. 39, pp. 1061.1074. Panayiotou, 1980, Proceedings, International Ophiolite Symposium, Cyprus, 1979, 781 pp. Wynn, J.C., 1980, "Exploration Geophysical Methods and Strategies, and Their use to Locate and Assess Small Mineral Deposits," Chapter 12 of Meyer and Carmen, eds., The Future of Small Scale Mining, McGraw-Hill, New York, pp. 75-83.

Jan 12, 1983

By John C. Nigro

Bench scale and pilot plant research was conducted using dolomites (CaO,MgO) lime as the basic additive in the preparation of self-fluxed pellets from a typical magnetic taconite concentrate (5.57 S_2). The specific objective of this investigation was to ascertain the viability of the magnesia lime pellets in high temperature oxidizing and reducing atmospheres. Pellet basicity and induration temperature were major parameters affecting fired pellet quality; temperatures ranging from 1,200° to 1,250" C appeared to be the most favorable for production of self-fluxed pellets with basesities (B) above 1.0. Comparison of the mechani¬cal and metallurgical properties of regular (acid) and self-fluxed pellets (B 1.55) produced under similar conditions in a modified grate pelletizing machine showed that the self-fluxed pellets were more resistant to abrasion and to high and low temperature reduction disintegration, an important consideration in commercial application. The Plus 3 mesh Linder index increased from 68 percent (regular pellets) to over 90 percent (self-fluxed pellets). The reducibility and swelling indices of the self-fluxed pellets were found to be comparable to the regular pellets.

Jan 1, 1972

By Weibai Hu

Four methods to assess the relative flotability of fine coal have been tested: flotation with frother only, flotation with frother and collector, salt flotation, and timed-release analysis. A practical and simple criterion which combines the separation efficiency (capacity factor and kinetic rate constant (intensity factor) has been suggested. Five coal samples are chosen and tested. Based on test results, it is concluded that the flotability test with collector and frother is closer to practice, and, according to the suggested flotability criterion, coal fines can be classified into four categories of relative flotability: very easy, easy, moderate, and difficult.

Jan 1, 1987

By W. Clark Ashby

Productivity is a fascinating concept. Like motherhood or apple pie, we know it as a good thing. Just what it means is not so clear. To a coal miner we assume it means tons of coal hauled from the mine. To the company president it means profit after capital, labor, and other costs have also been reckoned. To the government economist it means output in a balance of payments. What does it mean to the biologist, and can reclamation really be productive? In this paper we discuss productivity from a biological viewpoint, give some yield data for various types of reclamation plantings, and discuss how our demand for or acceptance of differing kinds of productivity is tied up in bigger questions of land use, environmental stability, and resource allocation.

Jan 1, 1981

By Veerendra Singh, NILAMADHABA SAHU, ARIJIT BISWAS

Manganese (Mn) ferroalloys are chiefly consumed in the steelmaking process as a deoxidizing agent or as an alloying element to produce high-quality steels. These alloys are typically produced in a submerged arc furnace using coke, fluxes and manganese ores of a specific manganese/Fe (Mn/Fe) ratio. Preferred-grade manganese ores should have Mn content greater than 46 percent and Mn/Fe content greater than 5 to produce commercial-grade, high-carbon ferromanganese [1]. Selective mining of high-grade Mn resources has created a scarcity of these resources, which is emerging as a major challenge for the manganese and steel industry. Manganese ore resources are mainly distributed in South Africa, with about 32 percent; Ukraine, with about 17 percent; Australia, with about 17 percent; and Brazil, India, China, Gabon and Mexico, with lesser amounts.

By Dr. R. W. Mead

There are two basic problems when one attempts to separate a solution of metal ions utilizing a chelation-solvent extraction cascade (commonly called liquid ion exchange). First, it is impossible to produce any great degree of separation unless the separation factor (also called selectivity, which is the ratio of the distribution coefficients) is very large. Second, the richest possible extracted product, using an infinite number of equilibrium stages, is at best only in equilibrium with the feed solution. These factors combined with equipment design considerations have led to a situation where only the most selective chelating agents are applicable to economic industrial operations. The authors know that distillation techniques are used routinely to separate compounds with nearly identical relative volatilities and that there should be a way of operating solvent extraction cascades in an analogous manner to obtain separations of metal ions. The advantage of this approach would be that solutions of metal ions of any desired purity could be obtained even if the separation factor was close to unity. This paper presents this idea and suggests some possible applications.

Jan 1, 1977

By James W. Clark

This paper is a description of certain geologic aspects of the Inspiration mining operation. It is not a geologic description of the Inspiration deposit nor an exposition of all the geologic work involved in the development and exploitation of the deposit. A few specific examples of the application of geology and geostatistics to the mining process are given to illustrate the progress that has been made in making the Inspiration Mine more efficient and cost effective, and a statement of the philosophy of geologic applications is offered.

Jan 1, 1984

By Rohan Fernando, David P. Snyder, John F. Burr, Susan M. Moore

"The Mine Improvement and New Emergency Response Act of 2006 (MINER Act Public Law 109-236) was passed by Congress in response to three major underground coal mine accidents in the United States that claimed the lives of 19 miners. The Act resulted in substantial changes in the underground coal industry relative to the use of technology for mine escape, rescue, disaster response and other areas where the lack of these technologies contributed to the fatalities caused by these tragedies. This year marks the 10th anniversary of the MINER Act, which makes it an opportune time to reflect on the events that led to its passage, the changes that have been made since then, and the work that remains to be done.As discussed below, the last decade has demonstrated tremendous cooperative efforts among mining operators, technology innovators, labor, The National Institute for Occupational Safety and Health (NIOSH), the U.S. Mine Safety and Health Administration (MSHA) and state regulators, resulting in substantial improvement of the technologies used for escape and rescue and noteworthy progress toward meeting many of the goals of the MINER Act. While the MINER Act and this article pertain primarily to coal mining, many of the technologies are equally applicable to any underground mining and have already found some acceptance outside of coal.Technology gaps targeted by the MINER ActThe MINER Act addressed several technology challenges:• Problems with donning and switching between self-contained, self-rescuers (SCSRs).• Poor visibility in smoke.• No wayfinding assistance for escape from the mine.• Limited breathable air supply.• Inability to locate trapped miners.• Inability to communicate with trapped miners.• Failure of mine seals."

Dec 1, 2016

By E. DeLilia

For the past 30 years, surface mines have moved toward more highly mechanized, automatic systems that continuously mine overburden and ore to in-crease productivity, lower operating costs and minimize manpower needs. To achieve these goals, mine operators must be involved in every step of the machine procurement process. Several factors are involved in making the machines operate economically and efficiently: ? Prudent engineering. ? Proper planning. ? Realistic feasibility studies. ? Effective specification. ? Thorough training of the mine personnel.

Jan 1, 1995

Exploration of new resources and development of new equipment and designs are an ever changing facet of mining. New equipment to handle specialized operations is being developed and new techniques for its use explored. One such system is reviewed. Another is a potential system for handling the thinner stray coal seams between the more profitable thick seams. The availability of federal coal leases in the West is reviewed and current planning discussed. Gulf Coast lignites have been of much interest in recent months and are overviewed.

Jan 1, 1979

By W. G. Pariseau

Reliable stress measurement using hollow inclusion gauges and monitoring stress change using borehole stress meters and borehole deformation gauges in anisotropic rock remains a challenge for the rock mechanics community. In this regard, the complex variable method advanced in 1983 for deducing stress in anisotropic rock is flawed and software is privileged. Fortunately, advances in computer hardware and software now enable fast, reliable reduction of hollow inclusion stress measurement data for determining stress in anisotropic rock. Monitoring stress change in anisotropic rock poses a different challenge but is also subject to numerical analysis. Stress measurement using a hollow inclusion (HI) gauge such as the triaxial Australian HI is done in four steps: 1) drilling a measurement hole, 2) installation of an HI, 3) stress relief of the HI by overcoring, and 4) data reduction. The last step, data reduction, is the focus of this work. The process is well-known in linearly elastic, isotropic rock (Worotniki and Walton 1976, Duncan Fama and Pender 1980). However, in case of linearly elastic, anisotropic rock the requisite technology is not readily available. This situation is somewhat surprising because anisotropy is more often the rule rather than the exception, especially in the neighborhood of ore bodies. Rahn (1984) has pointed out the potential for significant errors with neglect of anisotropy and the adverse consequences for engineering design. Amadei (1984) has also pointed out the potential for errors with neglect of anisotropic rock properties in stress measurement. Worotniki (1993) cites other studies that indicate potential for serious errors when doing measurements in anisotropic rock. In both theoretical cases (isotropy and anisotropy), data reduction is essentially a composite of solutions to boundary value problems in linear elasticity. In the finite element approach, the analysis is a simulation of gauge hole drilling, installation and overcoring. Two important advantages with the finite element approach are a more faithful representation of the conditions of HI stress measurement than approximated in theory and the capability for handling rock whether isotropic, transversely isotropic or fully anisotropic

Mar 2, 2022

By Jiayao Wang, Jian Chen, Leiting Shen, Hongyang Wang, Zeping Cao, Ziru Wang

Large amounts of by-products, including coal gangue, circulating fluidized bed (CFB) slag, and coal fly ash (CFA), are generated during mining, washing and burning of high alumina coal (HAC). The stockpile of these by-products of HAC will cause the pollution of air, water and soil. Meanwhile, the unbalanced regional distribution of bauxite and alumina production has been a critical challenge for the sustainability of world alumina refineries, especially for China. Therefore, economical extraction of alumina from by-products of HAC not only resolves the environmental pollution problems caused by stockpile but also decreases the dependence degree of import bauxite in China. Considering the fact that powder alumina can only be produced by alkali methods, the alkali extraction of alumina from by-products of HAC is summarized in this paper. Based on the formation process of by-products of HAC, the principle, research status, and problem of existing methods were analyzed and discussed, as well as the forecast of research trend. The analyses indicate that simplex recovery of alumina from byproducts of HAC generates large amounts of leaching residue (red mud) with difficulty for disposing, while comprehensive extraction of alumina and silica meets the research trend for clean and high-value utilization.

Aug 25, 2023

By D. Brandt

The Dos Pobres Mine is a copper oxide heap-leach operation located near Safford, AZ. Mine production is 163 kt/d (180,000 stpd) with a stripping ratio of 2:1. During the startup phase of the mine, the required fragmentation size was easy to achieve as the ore was highly weathered and fractured near the surface. As the mine depth increased, the proper fragmentation size became harder to achieve due to less weathering and different rock types. Because copper recovery increases as crusher product size decreases, achieving the appropriate product size at the crusher is the operating priority. The engineering department began a project to improve fragmentation through blasting and thus increase throughput in the crushing system. It soon became clear that input from other departments was going to be required to make this a safe and economical project. Therefore, the crush and convey and ore control departments worked together to evaluate all available data on blast patterns and explosive loads and tracked performance and results. Using image analysis, drill energy index and databases, improved fragmentation size has been achieved and results have been verified while controlling costs.

Jan 1, 2011

By A. Frank Alsobrook

DOUG HALBE: Thanks, Terry. And in spite of your introductory comments, I&apos;m going to attempt to continue our hallowed tradition of saying nice things about the speakers. This is really a serious comment now. We, as mineral processing and mill people, don&apos;t often talk to people outside our general operating area. One thing that we&apos;ve tried to do in this operators&apos; symposium is get speakers from various types of plant operations to help illustrate all the things we have in common. Our next speaker is from the industrial minerals area. I think there&apos;s a lot to be learned from industrial minerals operations. Some of the people in the last session learned some things about fine grinding in industrial mineral operations. I was a little surprised to see people there grind to 2 microns. Our next speaker is Frank Alsobrook. Frank is another nonmetallurgical engineer. He has a degree in geology, a master&apos;s of science from the University of Wisconsin. He&apos;s had his own very successful consulting company for a number of years. This is your 11th anniversary, Frank? Very good. He&apos;s also the immediate past chair of the industrial minerals division. I think the folks at the speakers&apos; table should be ashamed. You have been so rowdy that Frank chose to sit in the audience. [laughter] We&apos;d like you to come up now, Frank, and tell us some things that you&apos;ve seen that might be useful to us. INTRODUCTION FRANK ALSOBROOK: The three topics addressed briefly are (1) teamwork and operations modeling, (2) the pitfalls of capital conservatism, and (3) the potential for by-product recovery. Ideas for improvements in these areas are not unique to industrial minerals but apply to metal mining and processing operations, as well. Several additional topics are suggested at the end of the paper.

Jan 1, 1998