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Phelps Dodge has recently operated a commercial scale, super fine grinding circuit of copper concentrates for use in a medium-temperature pressure leaching process. Two 355 kW vertical stirred mills were installed in series, targeting a grind of 80% passing 7.5 µm and 98% passing 15 µm as outlined in Phelps Dodge's concentrate leaching patent portfolio. This paper details the operation and results of the test program at Bag dad, as well as some of the operating challenges encountered.

Jan 1, 2007

"INTRODUCTION While the United States coal mining uses prescriptive regulation under the Title 30 Code of Federal Regulation enforced by the Mine Safety and Health Administration (MSHA), Australia uses a risk based approach. Australian regulation is individual to each state. In Queensland, Australia this risk based approach to address principal hazards is underwritten by the Queensland Coal Mining Safety and Health Act of 1999 and the Coal Mining Safety and Health Regulation of 2001. Each Queensland Mine is required to have an overarching Health Safety and Environment Management System, of which Safety Management Plans are an element. “Safety Management plans (SMP’s) are intended to formalise the process by which mines address principal hazards and other related matters to ensure the safety of mine personnel.”7 THE QUEENSLAND CONTEXT In Queensland, the basic elements of a coal mine’s safety and health management system must provide for risk identification and assessment, hazard analysis, hazard management and control, and the reporting and recording of relevant safety and health information and data.5 (Part 2 Division 1 Section 6(a-d)) The initial guidance for writing Safety Management Plans comes from the Approved Standard for Mine Safety Management Plans and Guidance Note QGN09- Reviewing the Effectiveness of Safety and Health Management Systems. The Guidance Note and Approved Standard are supplemental to the Act and Regulation, and put in place to provide more clarity around the topic. The definitions in this section come from the Approved Standard and are included to provide context for those who may not be familiar with Australian or Queensland law and regulation. A hazard is defined as a source of potential harm or a situation with a potential to cause loss, while a principal hazard is a hazard with a potential to cause multiple fatalities. A risk is the chance of something happening that will have an impact upon objectives which is measured in terms of consequences and likelihoods. It is important to be able to make the distinction between a hazard and a risk. For instance, a lion is a hazard, while the risk associated with a lion is getting eaten. As defined by the Queensland Approved Standard for Mine Safety Management Plans, a Safety Management Plan (SMP) requires a systematic definition of all the actions necessary to ensure that mining operations are carried out safely. A SMP includes, but is not limited to organisational structures, planning, activities, responsibilities, practices, risk identification, audits and reviews.7 The goal of a SMP management plans is to mitigate the risks to bring them to an As Low As Reasonably Achievable (ALARA) level."

Jan 1, 2016

By Douglas F. Scott

This case study provides an example of how social marketing was applied to meet the needs of business customers. Federal regulations require that all companies develop a written program to track hazardous chemicals at their sites. The HazCom Writer, created by the National Institute for Occupational Safety and Health (NIOSH), is a software tool designed to help companies prepare their required Hazard Communications (HazCom) written plan and list all hazardous chemicals at the company's worksite. The social marketing goal was to provide a product for small- to medium-sized companies to use for federal HazCom rule compliance. The HazCom Wm'ter is a direct NIOSH response to customer and stakeholder needs (including the Mine Safety and Health Administration, the mining community, and Occupational Safety and Health Administration- regulated companies).

Jan 1, 2009

By C. K. Leith

CERTAIN ideas on iron and steel sanctions to follow originated in a series of conferences held under the joint auspices of the War Department and Brookings Institute in Washington last spring. The views presented may be regarded as those of substantial segments of the steel industry. In view of the fact that steelmaking capacity can be so quickly converted to the production of armament, any effective control must necessarily include the entire steel industry and not solely the parts devoted to the production of implements of war. It must also be exercised all the way from production and shipment of raw materials through their ultimate conversion into finished products and use. Control will be dis- cussed under two main headings: (I) control of raw materials at the source; (2) control of steel capacity within the Axis countries.

Jan 1, 1944

By ERNEST W. ELLIS

MORE or less contradictory findings as to the most satisfactory feed for concentration tables of the Wilfley type is shown by the diversity of opinion among experimenters. Prof. R. H. Richards,l as a result of his work, favors classification. On the other hand the work of Messrs. Cox, Gibbins, and Porter,' of McGill University, points in general to the desirability of screen-sized feed The ore used was obtained from the West mill of the Bunker Hill and Sullivan Mining and Concentrating Co., Kellogg, Idaho, and consisted of argentiferous galena in a gangue of quartzite and siderite. The natural feed was taken from the launder supplying the Fahrenwald classifier. Classified feed was collected from each of the ten spigots of this same classifier. From the natural feed the screen-sized feed was pre- pared in the laboratory. All three types of table feed were therefore derived from the actual mill circuit of a large plant.

Jan 1, 1926

By J. WILLIAM WETTER

WHEN the privilege was extended to me to address this meeting I could not help but make a mental review of my own activities and experiences in connection with association work. After having spent about 16 years in the mining engineering field, I entered into the operating branch of coal mining which afforded, about 12 years ago, my first opportunity of attending a meeting of our local Association and sitting in with the "big boys" of the industry. This was quite a thrilling experience because I had heard a great deal about the various operators who belonged to the Association and knew, or at least thought I knew, that a certain group dominated its affairs and that a "clique" was in control of a sizable "roller" which could be "steamed up" at will to flatten out any opposition which might appear upon the horizon or under it, too, for that matter. Now, I was to have the privilege of observing this "clique" at first hand, of seeing a small group making the policies and shaping the destinies of a great industry and planning the activities of an important Association while a large majority of the members would sit by either complacently or otherwise with the full knowledge that the "roller" was in waiting to reduce them to ribbons at the first sign of resistance.

Jan 1, 1930

By Elaine T. Cullen

Safety training materials appropriate for specific underground noncoal operations in the United States are often outdated or nonexistent. The Spokane Research Laboratory (SRL) of the National Institute for Occupational Safety and H ealth has developed several new training tools, including three videos on common underground activities, software that will allow trainers to create a virtual training mine using their own mine map, and toolbox training materials. SRL is working closely with industry in the development of these tools. Teams of safety professionals are involved in the early stages, and actual mines and miners are involved throughout the production phase. This presentation describes the development process and results of SRL’s safety training projects.

By Jovanir Francisqueto, José Fagundes, Nayara Neves Coutinho, Marco Túlio Costa

The purpose of this project is to increase the visibility of which will be daily produced on the hot strip mill (HSM). The forecast was performed through the implementation of an automated tool for weekly HSM production planning. The project was started with the definition of the weekly planning process, through the determination of the main business objectives, like as: priorities of service (customers and delivery date), definition of HSM’s rules and restrictions of operating resources. Using a sophisticated mathematical model, through the computational simulation is possible the experimentation of various production scenarios, allowing the visualization of volumes by type of sequence, clients / priorities, mix to be produced, cylinder change quantity forecast, better forecasting of the productivity of the HSM, consumption of utilities, within others. Main benefits: sequencing which production orders should be produced, reducing unforeseen stops due lack of material, improving the quality of the stock which allows the reduction of the aging of slabs in the slabyard and the vision of customer services. Computational simulation as a weekly planning tool achieve, with other benefits, to present alternatives for better decision making.

Oct 6, 2019

By Dan Witkowsky

In an increasingly environmentally conscious world, mining's importance to society has often been misunderstood and even maligned by the public. Extreme and impractical ideas have often been presented to children because of the lack of accurate, timely resource materials available to educators. In the late 1960s. two mining engineers, S.P. "Pi" Warren and C.L. "Lindy" Barker, became aware of this situation. They proposed to develop a summer field course to provide a factual overview of the minerals industry for teachers. The pair believed that teachers could become better informed to educate students, and future generations, about mining. These two Colorado Mining Association (CMA) members felt that such a course could reduce much of the misunderstanding about this vital industry. This could be done by providing a balanced perspective of mining, not only for kindergarten-through-grade-12 teachers, but also for the students they would be teaching during their careers. Students who better understood the minerals industry could better formulate an unbiased view of it. The course would seek recognized authorities from industry, academia and government who would lecture in their respective fields of expertise. The course would provide a total concept of the coal, aggregate, metals and industrial minerals industries. It would include geology, geophysics, exploration, mining, processing, marketing, product applications, economic, mining history, careers, and environmental responsiblity. When possible, site visits would permit educators to view operations and to meet the men and women who are industry leaders. Teachers would pay a small tuition fee. The balance of the program expenses for each teacher would be paid through scholarships provided by industry and individuals. The "total concept" idea obtained the support of the minerals industry. The support of CMA's Education Committee and the Colorado School of Mines (CSM) was obtained in 1968. Colorado's Commission on Higher Education approved teacher recertification credits through CSM's Office of Special Progams and Continuing Education for those successfully completing the program. The first six-week series of classes presenting the total concept of the indus¬try was held at CSM in 1969. In 1977, the CMA Education Foundation Inc. (CMAEF) was established as a Colorado nonprofit corporation. The "Total Concept of the Mining Industry" (Total Concept) course was placed under its sponsorship. CMAEF is dedicated toward this continuing education program (Table 1). In 1994, the course was streamlined to four-weeks for six hours recertification credit.

Jan 1, 1997

By Clint L. Milliken

The smelter is often considered the flywheel of the copper industry. No other unit can produce such a uniform product from so many starting materials. Direct-smelting ore, concentrate, precipitate, refinery slag, and scrap in almost any combination can be processed into blister or anode copper. Copper smelting practice has advanced little in the last century. It is still basically matte smelting, although the source of matte has changed from the blast furnace to the reverberatory furnace because of changes in smelter feed, and the Great Falls converter has been replaced by the Peirce-Smith converter. This lack of progress has continued because the economic forces required to produce change have not been of sufficient magnitude. Traditionally, the smelting, operation has required only about 10% of the total cost of producing copper from its ores and this minor cost item has not warranted change until recently.

Jan 1, 1971

By DFI DFI

An Online Conference

By Alicia O&apos, Overbeck, Reardon

DIFFIDENTLY, because don'ts are rarely greeted with cheers; humbly, because I, myself, have never lined up with the irreproachables, I venture on the subject of manners for the mining camp matron. Mining camps can be divided roughly into two types-the large, opulent settlement that blooms like the rose about a strong mine in full operation; and the puny group of adobe huts, or calamina shacks, or even canvas tents flung down in the wilderness to shelter the gay pioneers of a shining prospect or the shattered survivors of a lost hope. Of the first, I know nothing; but in the second, I have spent some of my best years, and from its curious code of morals and manners, its comic hates and its unreasoning loves, its high impatience and its engulfing kindness, I have charted the narrow .and pitted path which must be trod by the woman who would success¬fully live therein.

Jan 1, 1936

Greater mining productivity requires a more efficient cutting process. The cutting force available from today?s mining machines has been optimized with respect to machine size and weight. Researchers have shown that when employing water-jet-assisted cutting, bit forces and drum torques can be reduced significantly, which may allow mining machines to become lighter and more efficient. The Bureau of Mines has initiated a program to develop a water- jet-assisted rotary cutting system using the conventional bit assisted by a directed water jet operating at moderate pressures (3,000 to 10,000 psi). This water-jet-assisted cutting system has the potential to improve cutting efficiency without increasing machine horsepower or water usage (beyond what is presently used for dust control) or requiring fundamental changes in mining practice. IR addition to improvements in productivity, other anticipated benefits of water-jet cutting include reduced generation of respirable dust, elimination of frictional ignitions, increased bit life, reduced fines, and fewer machine vibrations. The papers presented at this open industry meeting discuss the development of water-jet-assisted cutting technology and future application of this technology to a variety of mining techniques including roof drilling and longwall mining.

Jan 1, 1985

By Steven R. Davis

Voyageurs National Park in northern Minnesota, and a 30-mile radius area of influence on the United States side of the International Border, was examined for hardrock (nonferrous metallic minerals and diamonds) mineral potential and environmental sensitivity by the U.S. Bureau of Mines. The investigation also included an analysis of current Metallic Minerals Leasing Rules of the State of Minnesota, and the probable effects of changes proposed to the current rules by the State of Minnesota in order to "encourage mineral exploration and development." The study has determined that the proposed changes to the Minnesota State Leasing rules will have minimal, if any, impact on the likely, foreseeable levels of mineral-related activities in the State as a whole, and particularly, in the area of influence to the Park. Voyageurs National Park management was advised on the extent and character of the proposed rules changes, and on those items of concern meriting a specific and timely response by the National Park Service.

Jan 1, 1994

By J. E. Moyle

Rio Algom Corporation of Wilmington, Delaware is a wholly owned subsidiary of Atlas Alloys Inc., an Ohio Corporation, which in turn is 100% owned by Rio Algom Mines Limited of Toronto, Canada. Rio Algom is controlled by the Rio Tinto Zinc Corporation of London, England, which has subsidiaries and affiliated operations throughout the world. Rio Algom geologists first became interested in this Utah pro- perty in 1966, after preliminary drilling had indicated that a known orebody close to the surface appeared to continue on the dorm thrust side of a major local fault, known as the Lisbon fault. Accordingly, in 1968, arrangements were made to acquire what was known as the "Humeca Option", a total of 2,573 acres located in San Juan county in south-east Utah, 35 miles south-east of the town of Moab.

Jan 1, 1975

By T. T. Read, T. L. Joseph, F. H. Royster

In a preliminary study of the beneficiation of iron ores conducted by the Bureau of Mines, one of the authors (T. T. Read) found it necessary to ascertain, if possible, how much effect a decrease in the silica content of an iron ore has upon the cost of making pig iron from the ore. In the beneficiation of iron ores the most important impurity to be removed is usually silica, and the amount that can be expended on a beneficiation process to reduce the silica content of the ore is obviously determined by the amount of increase in the value of the ore after beneficiation. The price that can actually be obtained for a beneficiated ore is, of course, a matter of negotiation between the seller and the buyer, but since the relative value of different grades of iron ore must be chiefly based upon the cost of making pig iron from them, an approximation as to the effect which decrease in the silica content of ore has upon the cost of snaking pig iron is an important guide in estimating what probable average gain will result from subjecting an ore to a beneficiation process. A search of the literature failed to reveal any detailed statement on this important topic, but fortunately the data are at hand to permit making an approximate calculation of the probable effect. For the purpose of the calculation assume three iron ores with the following composition (natural):

Jan 1, 1924

By Terry L. Muldoon

This report describes development and demonstration of an upgraded stench fire warning system for underground wines. Current systems, which have been used since before 1920, release an ethyl mercaptan mixture into the mines' compressed and/or ventilation air during emergencies. Miners, when smelling ethyl mercaptan, evacuate the mine according to predetermined plans. These systems, while simple, have problems with safety and reliability. The upgraded system overcomes these problems. The system uses a different stench agent, is less toxic, less nauseating, and less corrosive than ethyl mercaptan. These combined with the feature of thiophane not reacting with iron oxides, makes the upgraded system safer and more reliable. The system also uses a combination of two simple principles: a standpipe with pressure balancing to provide a constant head, and a sized orifice to control the rate of release of the stench agent. This system enables the mine to release the agent for a longer period which provides better coverage and to ensure that miners will not be exposed to potentially toxic concentrations of the stench agent. The system is easy to operate, requiring only the turning of two 1/4-turn ball valves. The upgraded system has been successfully tested during two evacuation drills at an underground uranium mine. Using three injectors (one on the compressed air line and one on each of two intake air shafts), the system exhibited significant improvements in warning times over the mine's existing system. This report provides a detailed description of the system design and its demonstrated performance in two mine demonstrations.

Jan 1, 1981

By Jay W. Hawkins

Under an approved remining program, mine operators can remine abandoned coal mines without assuming legal responsibility for treatment of the previously degraded water, as long as the discharging waters are not further degraded and other regulatory requirements are satisfied. A U.S. Bureau of Mines review of 105 remining permits in Pennsylvania indicates that remining results in substantial reclamation of abandoned mine lands, utilization of significant quantities of coal, and reduction of contaminant loads (acidity and iron) from degraded mine drainage discharges. Normality tests performed on the water quality and flow data indicate generally nonnormal distributions and extreme right-skewness, tending toward lower values. The water quality of underground coal mines was observed to be more highly degraded in terms of acidity, iron, and sulfate than that of surface coal mines. The optimum baseline sampling scenario is 12 months in duration at a frequency of one sample per month. Analysis of water quality and flow rates before and after remining indicates that a majority of the mines exhibited either no change or a significant decrease in pollution rate because of remining. The discharge flow rate was the dominant controlling factor when the post-remining contaminant load was significantly better or worse than the baseline (pre-remining) load.

Jan 1, 2010

By Catherine C. Kilgore

The Bureau of Mines investigated the availability of lead and zinc from 104 domestic mines and deposits. Fourteen primary lead and fifty-three primary zinc operations with in situ demonstrated resources containing 27.3 million metric tons (t) of lead and 53 million t of zinc were subsequently evaluated. Potentially 17.5 million t of lead and 2.4 million t of byproduct zinc could be recovered from 14 primary lead operations. Economic evaluations performed in constant January 1982 dollars determined a long-run total cost per pound of recoverable commodity. Including a 15-pct discounted-cash-flow rate of return (DCFROR), 59 pct of primary lead was potentially available at or below $0.32 per pound of lead. Potentially 40 million t of zinc and 5.6 million t of byproduct lead could be recovered from 53 primary zinc operations. Ninety percent of the recoverable zinc is potentially available from currently nonproducing mines and deposits, and a weighted average of their long-run total costs was determined at $0.98 per pound of zinc. At a breakeven (0-pct) DCFROR, these non producing operations had a weighted average long-run total cost of $0.58 per pound of zinc. Sensitivity analyses illustrated that operations that recover byproducts were most sensitive to fluctuating metal prices, producing operations were more sensitive to increased smelter treatment charges, and nonproducing operations were impacted most by the DCFROR.

Jan 1, 1983

By Evan Just

?We are certain there is need for research in every phase of mining." This statement by R. M. Crump of the Jones and Laughlin Steel Company (047) paraphrases opinion widespread among mining people. It is undoubtedly true. In preparation for this presentation, 193 organizations were asked to describe their mining research efforts. 60% responded, The meaning of "research" was taken in several different ways. The continual efforts of progressive companies to improve themselves were reported as research. We will call this and any effort to solve specific and immediate problems "practical research". The continuing investigation of subjects of long range interest will be called "basic research".

Jan 1, 1961