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By Charles Morris, Patricia Petty

Charles Morris Minerals engineers have a new opportunity to shape their industry's future. They can help secondary school teachers in their own communities improve their scientific knowledge and thus be better prepared to teach their students. Local sections of AIME and other groups are being asked to sponsor expense-aid scholarships for teachers who complete the summer field course A Total Concept of the Mining Industry. Now in its 18th year, the six-week summer course is presented by the Colorado Mining Association Education Foundation Inc., in cooperation with the Colorado School of Mines Office of Special Programs Continuing Education. The course will be held June 9 through July 18. "In the past, we have been successful in soliciting support for teacher-scholars from many organizations, corporations, and individuals within the industry," said John Robertson, Jr., Foundation chairman. "Now we hope to enlist the help of engineers at the grass roots level in identifying qualified local teachers and giving them what it takes to participate in this continuing education program." Robertson said the course provides secondary school teachers, counselors, and administrators with a working knowledge of the mining and metallurgical industries. It also helps teachers recognize career opportunities for their students. "With the industry facing a challenging new era, we must have teachers who can relate the excitement of this challenge to their students. They will inspire future generations of resource finders, developers, and managers," he said. More than 670 teachers in 27 states, including 45 graduates of the "class of '85" have completed the course and gained six semester hours of graduate credit. The Foundation's Planning and Curriculum Committee meets regularly to develop the course outline and recruit the faculty. Lecturers are selected on their ability to communicate with people not familiar with the industry. Last year, 67 faculty members came at their own time and expense to discuss their specialties, ranging from exploration to marketing. Normally, teachers receive scholarship aid in the form of tuition and fees, and transportation and meals while on field trips. Expense-aid scholarships cover room and board on campus for those beyond the Denver-Metro area, and travel to and from Golden. "We hope to broaden the appeal and the geographical range of the program," Robertson said. Inspiration for the field summer program for teachers came in 1967 from a mining engineer, the late C.L. (Lindy) Barker, a 1931 graduate of the Colorado School of Mines. Barker and a group of concerned individuals convinced the Colorado Mining Association to accept sponsorship of the course in 1968. The Colorado School of Mines and its Office of Special Programs and Continuing Education agreed to be a co-sponsor to give it accreditation and provide physical facilities and coordination. The first course was held in 1969. Operating funds were solicited from industry to pay tuition, course material, the cost of a course coordinator, field trips, and overhead. Through the years, personal contact by an industry representative has been the most effective teacher recruiting tool. Through expense-aid scholarships provided by local sections of professional organizations, such as AIME, as well as CSM alumni and other friends, there will now be a greater incentive for more teachers to get to know the minerals industry and pass that knowledge on in the classroom.

Jan 3, 1986

By L. Sandbak

The Turquoise Ridge Joint Venture (TRJV) is located in northern central Nevada, and is situated within the Basin and Range province, near the northeast end of the Osgood Mountains (see Figure 1). The TRJV mine consists of typical Carlin type- gold mineralization characterized by low strength rock of altered limestones, siltstones, and mudstones. The weak nature of the ground facilitates the underhand cut and fill mining methods. TRJV has been working to optimize ground support and mechanize top cut drift sizes and eliminate operating hazards associated with jackleg drilling. Safety Factor analysis based on bolt strengths has allowed us to pursue larger sized top cut drifts and to evaluate bolt length sizes and spacing. Switching from jackleg sized drifts of 10?W x 10?H to a mechanized 12?H x12?W top cut drift design has the potential to decrease overbreak, provide more uniform drift design sizes and bolt patterns, and increase ore production by at least 38%.

Feb 23, 2014

By L. Alagha, L. A. Sanchez-Calderon

The existing methods for recycling lithium-ion batteries present initial hurdles related to the safe handling and preparation of the batteries to avert potential explosions. Submerging batteries in sodium chloride (NaCl) solution has become an acceptable industrial practice. However, the use of NaCl to discharge lithium-ion batteries rusts the batteries’ cases and releases metals which impacts the downstream processes that involve selective recovery of Li. This study aimed to determine the optimal concentrations and pH range of NaCl for the discharge of lithium-ion batteries for the purpose of minimizing the leach of Al, Co, Cu, Fe, Li, and Ni.

Feb 1, 2024

By Meghan M. Murphy, Derek Penrice

The Downtown Rail Extension (DTX) is principal element of the planned second phase of the Transbay Joint Powers Authority’s (TJPA) Transbay Program. When complete, this regionally critical project will connect Caltrain’s regional rail system and the California High-Speed Rail Authority’s statewide system to the Salesforce Transit Center in downtown San Francisco via a 1.3-mile tunnel. Studied since the 1970s, the DTX has now received environmental clearance, and key stakeholders are aligned on the project’s configuration and its expedited delivery. This paper describes efforts to optimize the DTX configuration and develop an informed project delivery strategy that incorporates construction industry feedback on project phasing, contract packaging, and procurement methods that accomplish the project’s budget goals.

Jun 13, 2021

By Barnettm Ray R.

As a result of the Farmington explosion, the U. S. Bureau of Mines commissioned the National Academy of Engineering to a determine what steps could be taken in a short time frame to significantly reduce fatalities as a result of underground fire and explosion in coal mines. Three areas were named by the Academy as having the greatest potential; survival, communications, and rescue. The Bureau subsequently awarded a $3-5 million contract to the Special Systems Division of Westinghouse Electric Corporation for the development of prototype equipment and procedures. These were recently tested in a simulated emergency situation and will be delivered soon. Contractor recommendations for utilization and for further development effort will be studied and appropriate action taken.

Jan 1, 1971

By Clement K. Chase

Although flotation is the generally accepted process employed to recover gold and silver as well as copper, lead, and zinc from primary sulfide ores, the metallurgical requirements for the treatment of massive sulfide ore deposits differ markedly in many respects from those employed for the more common disseminated porphyry deposits. In Arizona, some properties classified as other then massive sulfide deposits because of mining and geological characteristics have produced mill-feeds similar to those from massive deposits. Several such occurrences are noted. The process requirements for massive sulfide deposits and unique mill-design implications are discussed in the perspective of world-wide economic considerations and the individual regional metallurgical and economic constraints in the United States.

Jan 1, 1986

By J. M. Pachter

Property sales and acquisition are prominent features of today's coal industry. Before selling or buying a site, a company must know the property's economic net worth. Any evaluation of economic net worth would be inadequate if determinations of a property's environmental liabilities and costs were omitted. Short-term and long-term costs can result from liabilities related to reclamation, water treatment, subsidence, and hazardous waste disposal. A structured, interdisciplinary approach can aid in the delineation, summation, and scheduling of these costs and liabilities.

Jan 1, 1986

By Samuel Polinsky, Lawrence W. Bierman, Wayne Perkins

[A column float beneficiation plant using 9, 8.5 foot diameter, cells was constructed by the Simplot Company and the Smoky Canyon Facility in the fall of 1986 and has been in operation since May of 1987. The float beneficiation process was developed jointly by the Simplot Company and the Bureau of Mines (Salt Lake City, Utah) which incorporates the Bureau's bubble generator design and chemistry system based around the reverse float technology, (Albany Bureau of Mines, Application of Carbonate-Silica Flotation Techniques to Western Phosphate Materials, Rule, Dallenbach , Larsen, RI8728, 1982) . This chemistry has been modified by Simplot in both patented and unpatented improvements. The objective of the beneficiation process was to reducethe A1203 content in the overall pipeline concentrate by 0.2 wt z. Therefore, a process stream was identified in the mill circuit which provided an opportunity to isolate and treat 1100 tons per day of poor quality phosphate concentrates The process allows recovery of approximately 15% of the mill concentrates, otherwise unsuitable for fertilizer production. The alternative would have been to waste this ore. Wasting would have resulted in considerable ore loss, increased mining costs and required additional products grinding. ]

Jan 1, 1989

By Deepak Malhotra, William F. Riggs, Edward C. Dowling

INTRODUCTION Mining companies are In the business of making an acceptable profit on their Investments, It became obvious in the recent recession that economic profitability/viability depends on being the lowest cost producer In order to compete on a global basis. The burden of achieving this objective falls on the mineral manager. He must strive to produce a salable product in an environmentally acceptable process while continuously Improving the profit margln.(1,2) Metal prices fluctuate on a regular basis. They directly Impact revenue and hence operating philosophy. The mineral engineer needs to develop an optimum operating strategy to meet his overall objectives, One would expect that, In the modem era of complex computer models, it would be easy to develop an economic model to maximize profits and/or cash flow. Discussions with mill managers Indicate that one mine/corporation's optimum operating strategy is not necessarily optimum for another. This paper approaches the problems from basics "Economics 101" and Illustrates the complexity of developing a universal model which can be applicable to all mines. Case examples are used to illustrate the need for better communication to avoid the basic economic fallacy “that optimization of segments leads to optimization of the whole system.” TECHNICAL MODELS Technical models are a prerequisite to the development of economic models because they provide the necessary Input data to these models, The flow of material from a mine through the sale of the finished product is shown In Figure 1. The ore Is mined and milled, and the concentrate can be stored for sale or smelted and refined In-house or at a toll facility. The finished product(s) are held In Inventory until sold either through existing contracts or in the spot market. [ ] Fairly reliable technical models have been developed for mining, milling and smelter operations. Mine plans are developed to provide a good Indication of the relationship between production and cut-off grade. It is easier to change surface mine plans than plans for underground mines. However, there are limits to maximum production that can be achieved with existing equipment. It Is possible that mine benches may not be developed to handle additional equipment, even If It was purchased to enhance production. More often than not, the cut-off grade Is lowered to Increase throughput goals.

Jan 1, 1993

By M. Trim, Y. Sun, D. Tepavac, A. Kumar

Configuration of Rozelle Interchange Project’s ventilation system required design and construction of some of the largest and tallest underground civil caverns attempted in Australia. The paper focuses on the technical challenges of designing these caverns within a heterogeneous, generally weak sandstone under highstress conditions while providing a construction sequence that would align with the contractor’s preferred techniques and schedule. Various construction techniques were investigated, but ultimately an observational approach relying on a construction sequence and specialized instrumentation met both the designer’s and contractor’s requirements. Relevant data obtained from excavations and the construction monitoring program are presented within.

Dec 1, 2022

By Edward J. Cording, William H. Hansmire

INTRODUCTION The Washington Metro, a rapid transit system that will serve the District of Columbia, Virginia, and Maryland, has been under construction for about two years. Construction of the Metro by the Washington Metropolitan Area Transit Authority involves a large amount of cut and cover, soil tunnel, and rock tunnel construction. To aid initial construction and improve future designs, performance observations were undertaken on tunnels in the initial construction phase. The University of Illinois Department of Civil Engineering was engaged to carry out a comprehensive program of field observations and measurements for this purpose. One part of the program was on the first soft ground tunnel constructed in the system. The tunnel is a 2200-ft (670 m) twin-bore section, designated Contract A-2, in downtown Washington. Two objectives of this program were to determine the relationship of construction procedure to settlements and to observe the pattern of soil movement around the tunnel as an aid in evaluating underpinning criteria for nearby structures. A test section, consisting t three instrument lines located across the tunnel path, was established prior to mining in Lafayette Park to measure in detail both vertical and lateral soil displacements as the tunnel was mined through the section. The site was selected because it is free from surface structures and access for installation and reading of the instruments was convenient. Load and distortion measurements on the lining were also made within the test section; observations of construction procedure were maintained throughout construction.

Jan 1, 1997

By G. Duncan

Distinct trends in grinding mill technology have emerged in recent years. In an effort to optimize overall mill performance for the needs of the End User, broad measures of logistical speed, process flexibility, operational risk, and overall costs now exert greater influence on the specification of grinding equipment. As a result, innovative alternatives to conventional grinding mill structures, supports, drives, feed, and discharge configurations are now being offered and selected with greater frequency. This paper investigates these trends in grinding mill technology, utilizing optimization and decision-theory techniques. In particular, the paper considers how specific advances in process design, product engineering, manufacturing techniques, and mining operations continue to relax technological constraints, enabling further mill innovation. In this context, a methodology is presented, illustrating how proper selection and specification of grinding mill components and configuration can target an optimization of the four End-User performance measures listed above..

Jan 1, 1999

By J. S. Ross

The significance and role of industrial minerals in Canada differ from those in the United States, The smaller Canadian industry has recently become well diversified and self-sufficient in most commodities, However, it depends on exports, principally to the United States, for much of its market, Imports are small, but imports of several basic products manufactured from industrial minerals are large. This nation is a leading world producer of asbestos, gypsum, sulphur, nepheline syenite, titania slag, potash and barite. It has reserves in asbestos for at least 30 years enough potash to supply the current world's needs for 2,000 years and sulphur reserves for 40 years of current world demand, One of the ilmenite deposits contains enough titania to supply the current world demand for at least, 25 years.

Jan 1, 1964

By Shawn Benner, David Blowes, Carol Ptacek

A full-scale reactive barrier was installed into an aquifer impacted by acid mine drainage in August 1995 at the Nickel Rim mine site near Sudbury, Ontario. The primary mechanism of water quality improvement is bacterially mediated sulfate reduction and metal sulfide precipitation. Dramatic changes in the groundwater chemistry are observed with up to 90% decline in Fe (from >18 to <2 mmol L-1) and increases in alkalinity from <1 to >10 mmol L-1 (as CaCO3). Over a 3 year period, the rate of Fe removal declines by approximately 35%. Primary controls on barrier performance are organic carbon reactivity, groundwater temperature, and variable residence time within the barrier.

Jan 1, 2000

By Deepak Malhotra

Following a severe recession in the early 1980&apos;s, mining companies have taken significant steps to improve metallurgy and reduce operating costs. They do not view chemical reagents and the long-term relationship with reagent producers the same way they did two decades ago. This paper discusses the general perspective of changes that have taken place over the years, especially with respect to cost of production, selling price and environmental constraints. A cooperative program between the consumers and producers of chemical reagents is recommended to understand each other&apos;s problems and identify the present and future needs of the mining industry. This approach will be beneficial to the long-term survival of both parties.

Jan 1, 1994

By P. Pages, J. Lombard, F. Fagnant, G. Bresson

This study is devoted to the improvement of the decision-making process in occupational protection of uranium miners in France. Its purpose is to apply the principles which are recommended by the I.C.R.P. in the field of radiation hazards. These principles, which have introduced the notion of "optimization" in standard setting, suggest the importance of applying cost-benefit and cost-effectiveness analysis to this sector. The objectives here are twofold : to evaluate the present organization of radiation protection on the basis of a simulation model of polluted air flow in the mine (due to the decay of a radioactive gas, radon) and to develop cost-effectiveness analysis of the various radiation protection policies.

Jan 1, 1981

By J. A. Finch, Zhenghe Xu, Z. A. Zhou

The generation of microscopic bubbles by cavitation may enhance particle-bubble attachment and improve flotation performance. It is shown in this paper that tiny bubbles or cavities can be generated by strong shear and turbulence in high speed liquid flows. These conditions create the necessary pressure fluctuations in the bulk water to cause the local pressure to drop below a critical value. The formation of bubbles is favored by high dissolved gas contents to promote gas diffusion into the cavities, and by the presence of surfactants to provide some mechanical strength due to the adsorbed film. Experimental results on bubble formation by cavitation and consequent flotation of fine silica (d50 = 1.6 µm) are presented.

Jan 1, 1995

By Ulf Marklund, Stig Markstrom

Pioneering work with pilot scale autogenous grinding started in Boliden 1956. From 1961 to 1991 eleven fully autogenous grinding (AG) circuits have been installed at various concentrators within the Boliden company. A compact two-stage grinding system was de- signed in the beginning of 1970s. The system included a pebble extractor which feed the secondary grinding stage with grinding media. The APC grinding system (Autogenous/Pebble/Crusher) is a further development of the AG concept. A new design of the Boliden pebble extractor together with improved control strategy make the performance of the APC system suitable to almost any ore quality. The Boliden AG concept is probably the most cost efficient grinding system of today.

Jan 1, 1998

By Y. Ye, J. D. Miller

Certain bituminous coals are known to contain appreciable quantities of natural fossil or subfossil resin. Such resinous coals are found in the western US, particularly the Wasatch Plateau coalfield of UT. Some of the seams in this field contain an average of 5% resin. This fossil resin has been recovered by gravity and/or flotation processes since 1929. Resin concentrates thus produced are of low quality and are usually refined by solvent extraction. The purified resins are of commercial importance in the adhesive, coating, rubber. and ink industries, etc. An improved flotation technique has been developed which involves ozone conditioning to selectively float resin from high-volatile bituminous coal. With this flotation process, a concentrate product which contains 95%

Jan 1, 1990

By Hans Skretting, Abraham A. Dor

This paper briefly reviews the historical development of the Rotary Kiln-Electric Furnace Process, which was first applied commercially to the treatment of qarnieritic ores in New Caledonia in the mid-fifties. It describes various technological improvements introduced, since, in industrial plants or developed in pilot facilities where a wide variety of nickel oxide ores has been treated success- fully over the years. Major categories of ores are characterized. The effect of their physical and chemical properties on their performance in the electric furnace is discussed. The relationships between ore composition, ferronickel grade and slag composition are analyzed and their effect on slag and metal tapping temperatures, nickel recovery, and electrode voltage are discussed.

Jan 1, 1979