Search Documents

By Richard Cole

The Energy Act of 1992 has many users of ac-induction motors eyeing premium-efficiency motors with mixed feelings and perhaps some confusion. When the October 1997deadline arrives for compliance with the1992 standards, the winners will be the environment due to reduced need for more power generating plants and the petroleum economy because of reduced dependency on foreign oil. But what will it mean for industrial users? The most obvious benefit is the potential for smaller electricity bills. Motors account for about 64% of the electricity consumed in the United States, at a yearly cost of $112 billion. Every 1% reduction in motor demand cuts 0.64%, or $716 million, off the industry wide bill. Higher efficiency motors also run cooler. This lightens the load on air-conditioning systems and further reduces plant demand. Lower total demand can lead to lower rates by helping to minimize peak-demand surcharges. As rates increase over time, these savings get bigger.

Jan 1, 1996

By P. C. Dagneau

QUEBEC CARTIER MINING COMPANY was incorporated in 1957 to explore and develop low grade iron are deposits in Northeastern Quebec. Four separate deposits were located and identified as being of ore quality and size to support commercial development. Said deposits were located at Lac Jeannine, Mount-Wright, Fire Lake and Mount-Reed. In 1970, in preparation for the replacement of the depleting Lac Jeannine are reserves, construction of an SS-mile railway extension was initiated, towards the newly selected mine site at Mount-Wright. This orebody was selected because the physical and chemical characteristics of the ore were very much similar to those of Lac Jeannine, as well as its huge reserves, estimated at more than one billion tons. In addition to the railroad extension, a mine, concentrator and related facilities were constructed and the new town of Fermont was created. Total investment for the Mount-Wright project exceeded $700 million and initial production commenced in 1976. Quebec Cartier is presently (1992) the leading producer and seller of iron ore in North America at 15,5 million tons and employs some 2,300 people.

Jan 1, 1993

By S. Mendenhall

The Golden Sunlight Mine (GSM) began operation in 1982 with a strong commitment to environmental stewardship and the local community. This commitment ensured the long-term physical, chemical and ecological stability of the mine site and maintained an active partnership with local stakeholders. Concerns for economic development intensified as mine closure loomed on the horizon and fostered the inception of the Community Transition Advisory Committee(CTAC).This coalition of interested area stakeholders has the primary focus to sustain current mining operations while concurrently seeking alternative post-mine economic development opportunities utilizing existing mine assets. Accomplishments include development of an Asset Re-utilization and Post-closure Plan, a community survey regarding the impending mine closure, recruiting an international wind energy company to develop a wind farm, and development of an industrial/business park. The synergy of this strong partnership is key to meeting sustainability goals and enhancing potential future mining operations. The cooperative effort of the GSM and the local stakeholders is a success story that could be a role model for other mining operations.

Jan 1, 2004

By Richard J. Lundin

Literature research is an inexpensive, yet effective tool for the direct discovery of ore deposits. Case studies abundantly demonstrate that properties with viable mineralization and *proven reserves have been overlooked, forgotten. or ignored and can be rediscovered by inexpensive literature search techniques Areal studies s as WaIlaby Enterprises Mining District Data Base Program appear to be more effective than traditional commodity studies. The success of such studies depends on the inclusion of Mineral Clairant Questionnaire Data, Mineral Ownership Data, Field Examination Data and the continual updating of all information. Such studies are valuable for proposed or existing Wilderness Area Evaluations.

Jan 1, 1977

By Joseph Goessling, Mark Kroncke, James Parkes

The I-35 Capital Expressway (CapEx) Central Drainage Tunnels will serve as a stormwater collection system for the forthcoming I-35 Capital Express Central reconstruction project through downtown Austin, Texas. The schematic level concept design included three tunnels, 10 to 14 ft ID, totaling 26,000 LF. Constructability reviews during design development indicated issues with the concept design including phasing of construction, conicts with future retaining walls, staging area concerns, and signicant mixed face tunneling. The design was updated to mitigate these risks. The revised design includes two tunnels, both 22-ft ID and totaling 33,000 LF, that will be mined almost entirely in rock.

Jun 23, 2024

By Georgene Renner, Chee Theng, William Gleason

"More than 6,300 people attended SME’s 2016 Annual Conference & Expo in Phoenix, AZ and many of them made the trip to the conference to take part in the excellent technical sessions that are presented on a yearly basis by the Society.Holding true to form, this year’s conference was full of options. In fact, this year there were 121 technical sessions and 751 presentations to chose from. The following is a sample of some of the technical sessions as seen through the eyes of the editors of Mining Engineering and SME technical papers.SME Sections Sharing Success: Changing thePublic Perception of MiningThis session was a workshop on how several local sections were effective in getting the message out to their communities and schools about the value of the extractive minerals industry. Several sections shared their outreach successes, including the Mining in Society merit badge activities by the Minnesota Section by Julie Lucas and SME’s participation in the World Scout Jamboree in Japan by Frank McAllister.Dan Alexander highlighted activities by the Pittsburgh Section, such as preparing minerals kits and pamphlets for elementary school classes and regional science fairs. The West Virginia University Student Chapter used the kits as handouts at their local gem and mineral show. School speakers in full mining gear were especially interesting to the young children.Other speakers were Michael Linn, Paradise Valley Unified School District — Business and School Partnerships; and Greg Kruse, Central Wyoming Section of SME — What makes a successful section?Engineering Competency ModelAmerican Association of Engineering Societies and the U.S. Department of Labor, with a grant from the United Engineering Foundation, developed a guide to the set of skills necessary for success in the engineering community -- Knowledge – Skills – Abilities — needed for all disciplines.Various engineering societies are now writing the Tier 5 occupation-specific requirements. The Competency Committee is charged to write concise and discipline-specific mining engineering, mineral processing engineering, geological engineering, and geophysical engineering by Sept. 30, 2017."

May 1, 2016

By I. Mikov

Established in the 60-ies, the Zlatna Panega quarry is a cement raw materials quarry supplying 95% of the needs of the Zlatna Panega Cement Plant with limestone, marl and other silica-aluminates. The two major types of raw materials are formed by accordingly dipping strata of Upper Jurassic limestones and lower Cretaceous marls. Between them there is a ?transition-zone? or ?contact-zone? of a high-silica content layer, about 5-m thick, defined as ?flint? by investigations including spot sampling throughout the quarry. For many years this ?contact-zone? layer was neglected due its negligible thickness. Further, with the increasing demand on the quality of the raw materials feed to the Plant and the focus on variability of the chemical and mineralogical components, it was decided not to mine any of the parts of the quarry contaminated by this material, for about three years. The latter had an impact on the availability of operating benches that could result in a substantial decrease in the total recoverable re-serves of Zlatna Panega, particularly with respect to marls. There were considerations for resorting to a partial, selective excavation of the quarry pit with a reduced lifetime for the lime-stones and re-opening of an other (currently in-active) marl quarry at a distance of 6 Km from the Plant. The Quarry Team of the Zlatna Panega quarry was assigned to study the problem. The ?contact? layer was duly confirmed with systematic geological (including mineralogy) studies, statistical analysis of available data, surface sampling and shallow exploration drills, resulted into distinguishing a third type of reserves and their credible subsurface delineation by means of geological 3-D modeling and quarry design. A new quarry design was finally elaborated with a view of providing flexibility in mining, utilization of the total volume of all available reserves and maximizing the mine life of Zlatna Panega quarry. An industrial test took place in December 2005, by using the contaminated parts of the quarry (co-mining of the ?contact-zone? materials) at a contribution of 15-20% in the raw materials mix, as dictated by their contribution in the total recoverable resources of the quarry. The purpose was to investigate the viability of this solution ? in line with improved quarry planning ? without compromising the quality of cement production and the efficiency of Plant Operations. Results were overall successful.

Jan 1, 2006

By George O. Lower

The use of cyanides in the extraction of gold and silver is well known.1 Such extractions employ con¬centrations of cyanide in the range of 0.02-0.25 % sodium cyanide equivalent in leaching cycles of 24-48 hours and frequently longer. Copper minerals, even though minor components of precious metal ores, dissolve in these cyanide leaching solutions, consume cyanide, cause fouling of mill solutions, and thus interfere with the precipitation and recovery of gold and silver. 2,3,4 This paper presents a summary of laboratory investigations on the use of cyanide solutions as extractants for copper from various copper-bearing ore fractions. In view of the metal contents involved, it will be apparent that larger quantities of cyanide are required to extract copper than for the extraction of precious metals. In cyanide solutions of concentrations generally favorable to copper extraction, sulfide and oxide copper minerals were found to dissolve rapidly at room temperature and atmospheric pressure. For example, on products in the flotation size range, the major portions (e.g. 65-85%) of the extractable copper frequently dissolved in 2-10 minutes. At coarser grinds, e.g. 100% minus 28 mesh and 100% minus 10 mesh, 75-85% of the total copper was extracted in 30 minutes.

Jan 1, 1966

By Adeyemi Adesina, Subhabrata Mishra, Syed Mohammed Mustakim, Malaya Kumar Jena, Shaswat Kumar Das

Utilization of low-grade manganese ore adopting the carbothermic reduction roasting process is a proven method to produce high-grade manganese ore. To minimize industrial waste and protect the environment, gas cleaning plant sludge (GCPS), which is a solid waste from steel industries, was employed as a reductant to perform the reduction roasting process. The optimum conditions to carry out reduction roasting of the low-grade manganese ore were found to be: a roasting temperature of 950 °C, a residence time of 2 h, 40% GCPS as reductant, and magnetic separation at 5000 G for a manganese ore size of –10 mm. A lowgrade manganese ore comprising Mn grade 31.27% and Fe grade 19.78% having a Mn/Fe ratio of 1.58 containing a high silica content of 26.48% was used for the carbothermic reduction roasting having mineral phases of pyrolusite (MnO2) and hematite (Fe2O3) as found from XRD. The gangue minerals were separated during the magnetic separation, and the upgraded product was obtained, which reached a maximum value of TMn 49.5% with RMn 76.55% and TFe 62.19% with RFe 42.51%. In the study, activated charcoal (AC) was also taken as a reductant for comparative analysis; the experimental results revealed that GPCS performed better than that of the AC, showing potential to be used as a reductant in metallurgical industries. However, the resultedMn/Fe ratio was very low for the reduced sample; therefore, it can be used for smelting along with high-grade manganese ores as a feed.

Mar 5, 2021

By H. J. Bickel

This paper is concerned with general concepts and statistical devices used in projecting overall energy requirements. Particular emphasis is given to the use of individual end- use markets as an approach to developing future overall energy requirements, and translating these requirements into fuel consumption.

Jan 1, 1962

By A. Güngör, Ü. Atalay

Thermal treatment can significantly improve industrial comminution operations by reducing energy requirements and increasing mineral liberation. The assistance of thermal pretreatment prior to grinding by microwave heating is scrutinized in this study. For this purpose three copper ore samples with different chemical composition were used. To see the effect of microwave heating on ore; work index, breakage rate and breakage distribution functions of original and heat treated samples were examined. The results obtained in this study did not show significant improvement in the grindability characteristics of the studied ores with microwave heat treatment. The inadequate amount of microwave transparent matrix was the main reason for the absence of cracks and micro-fractures in the microwave heated copper samples.

Jan 1, 1999

By D. P. Tao, J. G. Groppo, R. Killmeyer, W. W. Wen, B. K. Parekh

Economical dewatering of ultra-fine (minus 74 m) clean coal slurry produced in column flotation to a 20 percent or lower moisture level will be an important step in successful implementation of the advanced fine coal cleaning processes. The main objective of the present study was to evaluate efficiency and effectiveness of three dewatering techniques, namely, hyperbaric, vacuum and screen bowl centrifuge, in dewatering of ultra-fine (D50 ~ 25 m) clean coal slurry produced by the `Ken-Flote' columns operating at the Powell Mountain Coal Company, St. Charles, Virginia. he hyperbaric filter using 3 bar pressure and 165o cake formation angle, provided a filter cake with 23.6percent moisture with a throughput of 800 Kg/m2-h and air consumption of 868 Nm3/t (460 scfm/t). The vacuum filter with 30 percent submergence provided a filter cake with 27.8 percent moisture with a throughput of 122 Kg/m2-h. The screen bowl centrifuge provided a dewatered product containing 32.9 percent moisture at a feed rate of 450 Kg/hr, however, the solids capture was only65 percent. Addition of 1 Kg/t of a cationic surfactant provided filter cakes with 19.1 percent, 23percent, and 34 percent moisture using hyperbaric, vacuum, and centrifuge, respectively. Similarly, addition of 0.5 Kg/ton of copper chloride lowered filter cake moisture to 20.7 percent and 24.8percent, using hyperbaric and vacuum. With the centrifuge no improvement in filter cake moisture was noted. However, use of 80 Kg/ton of `orimulsion' in the centrifuge provided dewatered product containing 26 percent moisture, and the solids capture increased from 65 to 95 percent. The dewatered product appeared dry and was easily handleable.

Jan 1, 1999

By A. E. J. Gallagher

There are many influences which have a bearing on the economics of industrial minerals production. The purpose of this paper is to discuss briefly three factors which have economic significance in the production of these mineral commodities. The three items of discussion include 1) the nature and relative value of the industrial minerals group, 2) project planning, and 3) market analyses. General aspects of these factors are familiar to most of us. However, an attempt will be made to give some current details regarding each. Also, in reality, project planning and market studies are usually so closely associated that they will be discussed jointly, rather than separately. This will be done by way of examples which show how these two activities actually evolved for two industrial minerals projects.

Jan 1, 1984

By Chee Theng

"Getting minerals out of ores is messy, but mineral processors learn to have fun with it. Celebrating the innate joys of the industry was the theme of this year’s Colorado MPD Conference. At the same time, attendees dug deeper for insights into problems that continue to dog the community, including tailings dam crises, water resource challenges, and a dwindling number of academics to teach and train the workforce (see box).Tailings dam crisesMatt Fuller of Tierra Group International Ltd. brought some of the audience to tears with his impassioned talk on “The Infamous Legacy of Upstream Tailings Dams,” which won the conference’s Lou Cope award for best paper. The talk was especially poignant coming on the heels of the January tailings dam failure in Vale S.A.’s Córrego do Feijão iron ore mine in Brazil, the latest in a series of catastrophic dam failures over the past decade that includes the Fundão dam failure in 2015.Noting that the two dams share a common characteristic — both are upstream tailing dams — Fuller explained the three basic dam construction methods and why certain upstream tailing dams are susceptible to failure (Fig. 1). The downstream, centerline and upstream methods denote the direction the centerline of the dam crest moves with each successive raise in elevation of the dam. With the downstream dam, the foundation for future raises is essentially the same as that of the starter dam, he explained. With the centerline dam, half of the dam is constructed on the same foundation as the starter dam, and with the upstream dam, each successive raise is built out over the top of the tailings.“Downstream dams are expensive to build because each successive raise is bigger, so the sustaining capex to build them keeps growing,” Fuller said. Many decades ago, mine owners realized they could construct a starter dam, put their tailings through a hydrocyclone, generate a coarse sand fraction and stack the sand over the top of the tailings to build the next raise. “Then, there is no sustaining capex, it all comes out of operations,” Fuller added. The footprint is smaller, and it is a favorable means of retaining the tailings."

Jul 1, 2019

By Timothy D. Arnold

Barrick Gold’s Bullfrog underground mine, near Beatty, NV, was established as an after-thought to the main open pit. As open pit ore dwindles, the underground mining became increasingly more important as an ore source, and to the overall economics of the project. This situation is similar to many other mines. Today, there is a move towards underground mining in the United States. There are inherent problems in starting and operating underground mines in the shadow of any open-pit operation. Several attempts were made at the Bullfrog Mine for productive increases. Some were successful, while others were not.

Jan 1, 1996

By Wesley W. Eckles

Microcomputer technology has begun to revolutionize petroleum engineering. Petroleum engineers' use of relatively inexpensive personal computers (PC's) is likely to continue expanding rapidly. Since 1982 SPE's Microcomputer Applications Committee has developed a Society-wide users group, a bi-monthly newsletter (MICROCOMP NEWS), an SPE Short Course, a hardware and software distribution program, and a world wide electronic network (SPE NET). The purpose of this paper is to share SPE's experience in creating a dynamic program for meeting the individual member's need in the application of microcomputers to petroleum engineering. My hope is that this will encourage other engineering and scientific organizations to provide similar programs for their members.

Jan 1, 1985

By Juan Camus

To understand why some companies excel in creating value, Jim Collins (2001) and a group of postgraduate business students engaged in a comprehensive, five-year research project. They examined 1,435 U.S. companies for more than 40 years, seeking those that made significant improvements in their financial performance over time. The distinctive pattern sought was: ?Fifteen-year cumulative stock returns at or below the general stock market, punctuated by a transition point, then cumulative returns at least three times the market over the next 15 years. ?The search identified 11 outperforming companies, all in different industries, that were called the ?good to great? companies. To contrast these companies with similar peers within the same industry, the search also selected a group of comparison companies that failed to make the leap from good to great. Collins then set out to examine the transition point. What distinguishing features did the good-to-great companies have that their industry counterparts did not? At the heart of the findings about these outstanding companies is what Collins refers to as the ?hedgehog concept? ? how to find the one big thing that the company must focus on. According to Collins, those who built the good-to-great companies were, to one degree or another, hedgehogs. Those who led the comparison companies tended to be foxes, never gaining the clarifying advantage of a hedgehog concept, being instead scattered, diffused and inconsistent. This insight is complemented by Peter Drucker (2004), an influential management guru, who asserts that the first question an effective executive should ask is: ?what needs to be done?? Asking this question and taking it seriously, he asserts, is crucial for managerial success; and that the answer almost always has more than one urgent task, but the effective leader only concentrates on one task. In this last respect, Drucker emphasizes: ?If they [executives] are among the sizeable minority who work best with a change of pace in the working day, they pick two tasks. I have never encountered an executive who is effective while tackling more than two tasks at a time.?

Jan 1, 2011

By J. T. YIi-Penttiia

Dust formation and reaction mechanisms of copper matte particles were investigated in simulated flash oxidation conditions. The granulated and ground matte consisted of 72 wt% Cu, 4 wt% Fe and 21 wt% S. Experiments were conducted by using a laminar-flow furnace with a reaction gas composition ranging from 20 vol% to 75 vol% O2 in nitrogen. The particle feeding was carried out by the single-particle method and samples were quenched after a specified reaction time (approximately 0.05-004 s) in a cold water film. Experimental temperatures were between 800 and 1300°C. Chemical analysis was used to determine oxidation degree, and an optical and scanning electron microscope combined with energy dispersive analysis was used for characterization of the reacted particles.

Jan 1, 1998

By Jr. Pitts

Elevation of surface charge density on colloidal particles in the presence of a high potential electrostatic field is demonstrated as a viable technique for preventing the accumulation of solids in solvent extraction circuits. The effect of the technique is manifest by relative turbidity measurements between pregnant leach solution and raffinate, by changes in the character of the sludge accumulations, by alteration of the zeta potential of particulates, and by a general reduction in the mass of solids.

Jan 1, 1992

By W. Lorenz

The responsible treatment of natural resources, including mineral raw materials, contributes to the protection of the environment. The management of resources and the environment encompasses reduction of emission through application of environmentally friendly processes, economical use of resources, recycling and substitution, application of energy saving processes, land reclamation and recultivation, as well as a well balanced regional and land use planning. A variety of materials are needed for measures to protect the environment. Many of these materials are, or to a large percentage consist of, mineral raw materials, which become effective either directly or indirectly in their natural state or after an appropriate industrial treatment. We call them environmental minerals. Although extraction and processing of these mineral raw materials destined for use in the protection of the environment, may have a negative impact on the environment on one hand, preventive or curing measures to protect the environment on the other would not be possible without them. We have to accept certain smaller burdens of the environment, which naturally will have to be kept at the lowest possible level, in order to avoid or minimize greater damages to nature. In the broad group of industrial minerals and rocks there is a wide variety of mineral raw materials, which lend themselves for countermeasures in favor of the environment. To hamper their production and processing through excessive environmental regulations would make the protection of the very environment more difficult or even impossible.

Jan 1, 1995