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By R. J. Baumgartner

Sustainability issues are from rising interest and importance for the mineral industry worldwide. In order to bring them into management processes and to improve decision processes, economic, ecological and social aspects of products, services or technologies have to be assessed. In this paper, the concept of integrated sustainability assessment is presented. Each aspect is assessed with quantitative or qualitative methods. The results of these ecological, social and economic sub-assessments are integrated by the means of Fuzzy Logic in order to regard preferences of decision maker and circumstances of decision situation. An example demonstrates the application of this new instrument.

Jan 1, 2005

By R. N. Edmondson, L. Mair, M. Tenenbaum

It is the policy of The Metallurgical Society to provide, in the TRANSACTIONS OF THE METALLURGICAL SOCIETY OF AIME, a prompt and accurate medium for publication of reports of significant new research in both the scientific and engineering aspects of metallurgy. Papers submitted to the Society are judged by competent reviewers according to established criteria for technical merit, accuracy, originality, and presentation. STAFF: Editor, Dr. Gerhord Derge; Editorial Assistant, M. A. Redmyrski; Staff Coordinator, James J. Burke. THE METALLURGICAL SOCIETY: W. R. Hibbard, Jr., President; J. C. Kinnear, Jr., Past-President; John Chipmon, Vice President; T. D. Jones, Treosurer; R. W. Shearman, Secretary. PUBLICATIONS COMMITTEE OF THE METALLURGICAL SOCIETY: A. w. Thornton, Chairman; Dennis Carney, John Chipman, J. C. Fulton I. H. Hollomon H. H. Kellogg, A. E. Lee, R. Maddin, J. D. Sullivan, and D. Swan. Review and selection of manuscripts is under the supenision of the following Publications Committees: Extractive Metallurgy Division: T. 0. King Chairman; S. J. Dickenson, R. P. Hermsdorf R. Schuhmann. Jr.. and P. T. Stroup. Institute of Metals Division: Robert Maddin, Chairman F. Lincoln Vogel Jr., Vice-chairman, W. A. Baikofen, R. W. Boliuffi J. H. Bechtold M. B. Beyer. R S. Busk, C. G. Gaetzel, Paul Gordon C. D. Groham, Jr., Robert F. Hehe-mann,' R. I. Joffee, F. c. Joumot Jr lrving R. Kramer A. J. Lena Harold Morglin, C. J. McHargue, Russell A: Meussner, J. B. Newkirk H. W. Paxton, G. E. Pellissier, I. S, Servi, Alon U. Seybolt, A. J. Shaler, and Jack Washburn. Iron and Steel Division: J. C. Fulton, Chairman; T. B King, F. C. Langenberg, W. 0.. Philbrook, and T. 0. Winkler. Published bimonthly by the American Institute of Mining Metallurgical and Petroleum Engineers Inc., 29 West 39th Street, New York 18, N. Y. Telephon: pEnnsvlvanio 6-9220. Subscription 522 Per year for non-AIME members in United States and North South and Central America; $25 foreign;, $5 for AIME members. Single copies, 54.00, single copies foreign, $5.00. The AIME is not responsible for any statement made or opinion expressed In its publications . . . Copyright 1958 by the American lnstltute of Mining Metallurgical and Petroleum Engineers Inc. . . . Registered cable address AIME New York , . . lndexed in Engineering Index Industrial Arts Index and Chemical Abstrats . . . Application for second class mail privileges ii pending at New York, N. Y. Volume 212, Number 4.

Jan 1, 1959

By André Brasil

Dado que las represas de relaves construidas por el método de aguas arriba presentan deficiencias relacionadas con los aspectos constructivos y de seguridad, es difícil evaluar la variabilidad real del depósito basándose apenas en los procesos de campo. En ese sentido, el presente texto desarrolla un modelo para describir y simular el mecanismo de formación de las represas de relaves considerando las variables externas (concentración y caudal de descarga) e internas, así como muestra soluciones analíticas y numéricas comparados a nivel laboratorio.

Sep 9, 2007

By Dennis J. Riley

A. This outline addresses what a sub-contractor, or a subsub-contractor should do to get paid in the event the general contractor or building owner files for bankruptcy. B. Negotiating payment terms. Progress payments vs. "pay when paid". How a sub or subsub can avoid financing the contract. C. Court interpretation of "pay when paid" clauses allow postponement not excusal of payment. See, e.g., Seal Tite Corporation v. Ehret. Inc., 589 F. Supp. 701 (D.N.J. 1984) (where the court held that the general contractor could not delay payment indefinitely to the subcontractor in the event of non-payment from the owner); United Plate Glass Co. v. Metal Industries. Inc., 525 A.2d 468 (Commw. Ct. Pa. 1987) (where the court held that payment from owner was not a condition precedent to paying subcontractor but instead a timing mechanism indicating when payment should be made); But see. Straham v. Landis Construction Co., 499 So. 2d 417 (La. App. 4 Cir. 1986) (where the court strictly interpreted the "pay when paid" clause).

Jan 1, 1991

By T. Gammatikopoulos, C. Gibson, M. Aghamirian

Lithium is an alkali metal found in brine deposits in the United States, Chile and Argentina, as well as in hard rock deposits in Australia and North America. In hard rock deposits, spodumene (LiAl(Si2O6)) is the major economic lithium bearing mineral. Spodumene is typically upgraded through a combination of dense media separation, flotation and magnetic separation. One of the major spodumene concentrate quality specifications is the iron oxide content because it will help determine if the concentrate is considered ceramic grade for use in ceramics and glass or chemical grade for use in lithium ion batteries. The rejection of iron bearing silicate minerals from artificial ore composites (high amphibole and low amphibole, high quartz/feldspar) from a hard-rock spodumene deposit was investigated using magnetic separation and flotation. The efficacy of Wet High Intensity Magnetic Separation (WHIMS) in iron rejection was found to be dependent on the mineralogy of the iron-bearing silicate minerals including modal distribution, liberation and association. When magnetic separation was conducted prior to flotation, the Fe2O3 grade in the final flotation spodumene concentrate was reduced from ~3% to ~1% Fe2O3 , and improved lithium recovery in flotation was observed. It was determined that it was most effective to conduct WHIMS on the flotation feed after scrubbing and de-sliming because this reduced the required magnetic field to recover iron-bearing minerals, likely because slime coating was greatly reduced. Flotation collector screening of four different collectors with varying rosin acid content demonstrated a potential increase in selective flotation of spodumene over some iron silicate minerals with decreasing rosin acid content in the fatty acid collector. However, due to marginal difference in flotation results with the various collectors tested, further testing is required to confirm the observations made and establish a hypothesis regarding the effect of rosin acid content.

Jan 1, 2017

By Koch D. F A

An electrochemical study of the dissolution of gold in aerated cyanide solution shows that the dissolution rate is determined by the nature of the surface. A passive film (probably a basic cyanide) formed at -0·6 V vs a saturated calomel electrode inhibits both the anodic dissolution of gold and the cathodic reduction of oxygen. Thallium has an "activating" effect on these reaction mechanisms.INTRODUCTIONIn general the dissolution rate of a solid in a liquid is studied by weight loss measurements or analysis of the solution at known time intervals. However, if the solid is a metallic conductor, on which a redox reaction can occur at the metal-solution interface, it can be studied by electrochemical techniques. Electrochemical measurements have the advantage that the overall reaction can be separated into its components, in some cases by electrical measurements alone, and in others by a combination of these with analytical determinations.The overall equation for the dissolution of gold in aerated cyanide solution may be written4Au + 02+ 8CN- + 2H20 = 4Au (CN)2- + 40H- ..... (1)which can be separated into the two electrochemical componentsrepresenting the oxidation of gold and the reductionof ogygen respectively.4Au + 8CN-,= 4Au(CN)2- + 4eand O2+ 2H20 + 4e = 40H- These two reactions occur at the gold-electrolyte interface and it is the purpose of this paper to discuss the mechanism...

Jan 1, 1964

By Basil B. Zavoico

CRUDE oil production in the United States during 1938 reached approximately 1,214,355,000 barrels, an average of 3,327,000 barrels per day, or 5 per cent below the 1937 record output of 1,279,160,000 barrels. The decreased production did not prevent the stocks of all products from increasing to a total of 575,954,000 barrels by Sept. 30, an increase of 10,957,000 above the total on Jan. 1, or an average daily storage increase in all products of 40,135 barrels. The increase in total stocks was made entirely in the refined products, stocks of crude oil during the first nine months of 1938 having actually declined 7,155,000 barrels to 299,671,000 barrels, or an average daily decline of 26,209 barrels. The 1937 reversal of the preceding five-year trend of discoveries totalling less than withdrawals was continued through 1938 with indicated reserve addition from both new discoveries and extensions considerably in excess of the

Jan 1, 1939

By J Fut=

The rotary drilling of rocks is widespread technology in mining and in tunnelling. The paper describes the results of research by aim to find relationships between optimal drilling and sound signal of drilling machine. The optimisation criterion has been formulated as the minimisation of specific energy with maximal effective speed of drilling in process of the rock disintegration. The research in this field has been made on experimental drilling stand. Our monitoring system has measured following variables: the pressing force of core drill, the revolutions of drilling head, the length of drilling, the time, the power, and the acoustic signals. For measurement of acoustic signals have been used very sensitively sound meter MEDIATOR 2238. From this measurements have been processed acoustic spectrums. Then we are found relationships between optimal control of drilling and composition of acoustic spectrum. On base of experimental results, we can formulate the optimal control following: æTo achieve the minimum difference between the equivalent sound level at the load and idle modes only at the representative frequency (f = 1000 Hz)Æ. The representative frequency dependences on type of the rock New method based on these relationships enables the optimal control of drilling machine by using measured acoustic signals only.

Jan 1, 2003

By P. Botane, A. Cailleau

"Compagnie Miniere Esperance operates a gold primary ore body. The ore is processed through crushing, grinding and gravity concentration generating tailings with remaining fine gold. Analyses of the tailings proved a residual gold grade sufficient for a chemical treatment.As lab tests proved the technical feasibility of a pre-concentration using flotation, an on-site pilot operation has been carried out to assess the continuous circuit performances, define the best configuration and obtain enough data for the industrial circuit sizing.Data collected during the pilot campaign have been used for calibrating a process simulator built with the USIM™ PAC software. The simulator validated the feasibility of upgrading the existing plant, including the reprocessing of tailings to obtain a good fine gold recovery in a small amount of concentrate. A preliminary capital cost has been achieved to assess the flotation workshop profitability.INTRODUCTIONCompagnie Miniere Esperance (CME), a mining company based in French Guyana, operates a gold primary ore body in open pit. The ore is processed through crushing, grinding and gravity separation in two stages: a top plant and a bottom plant. A “coarse” pond contains tailings of the top plant; this product feeds the bottom plant. Tailings of the bottom plant are stored in the “fine” pond.Analyses of the fine ponds proved a residual gold grade sufficient for a chemical treatment. However, direct cyanidation would require a too large installation, regarding the local conditions (accessibility, supplying and meteorological conditions).It has been then decided to test the feasibility of a pre-concentration using flotation. Lab tests have been carried out by SGS Lakefield (Canada) in March 2007, which proves the technical feasibility."

Jan 1, 2009

By L. D. Patts, J. D. Noll, S. E. Mischler, G. H. Schnakenberg

In this study, we evaluated the ambient diesel particulate matter (DPM) concentrations (at the intakes and exhausts of the mine) as the entire vehicle fleet of a stone mine switched from using 35% biodiesel to using a water emulsified fuel (PuriNOx). Elemental carbon (EC) was reduced by 45% when a PuriNOx blend containing 10% water replaced 35% biodiesel and by 57% when a PuriNOx blend containing 20% water was used. Other factors such as engine duty cycle and production changes could potentially cause some day-to-day EC fluctuations, and no direct comparison to commonly used dieselfuels (No. 1 or No. 2) was achieved. Therefore, a second study was performed in a controlled “isolatedzone” environment to fametal mine, comparing PuriNOxto No.1 diesel fuel in a load haul dump vehicle. The EC fraction of the DPM was reduced by about 71% when the PuriNOx blend containing 10% water was used and by about 85% when the PuriNOx blend containing 20% water was employed. This study did not determine how the water emulsified fuel would affect the engine or power.

By S. P. Sandoval

Previous research by the U.S. Bureau of Mines demonstrated that nonionic surfactants increased the leaching rate of copper in the flask leaching of chalcopyrite with ferric sulfate if sufficient ferric sulfate was present. This research was continued by the Bureau in Part 2 to further explore the application of nonionic surfactants to the dump leaching of chalcopyrite. A polyoxyethylene lauryl ether was selected as the superior nonionic surfactant tested at 25° and 50° C. The addition of the surfactant increased copper leaching by 116 pct at 25° C and 1.0 pct solids and by 61 pct at 50° C and 0.5 pct solids at Fe 3+ concentrations greater than 1 g/L. At 0.1.0 g/L Fe 3+ and below, the addition of the surfactant produced as much as a 35 pct decrease in leaching. Each of the nonionic surfactants studied was found to be heavily adsorbed by a typical chalcopyrite ore, which poses a serious barrier to the application of nonionic surfactants in an actual chalcopyrite dump.

Jan 1, 2010

By R. M. Owens, J. F. Lupo

The Shirley Basin Uranium mine, located in southeastern Wyoming, USA, was an open pit mining operation consisting of a series of several open pit mines excavated into poorly consolidated sandstones, siltstones, and claystones. Since the initial open pits were developed in 1969, slope failures have plagued the mine and mining operations. These slope failures have persisted into the current mine reclamation period. When the mine was first developed, the open pit slopes were designed to range between 45 to 55 degrees. Numerous slope failures during mine development required the pit slopes to be redesigned with slopes as shallow as 26 degrees. At present, movements are occurring within the open pits on reclaimed slopes that are shallow as 12 degrees. Several detailed slope studies were conducted at the mine in the early 1970s. These studies, combined with more recent geotechnical investigations, provide a unique detailed history of pit slope failures on shallow slopes. This paper presents an evaluation of the slope failures at the Shirley Basin mine, highlighting important mechanisms causing slope failures on very shallow slopes. The evaluation demonstrates important key parameters for shallow slope design.

Jan 1, 2001

By Ron Lutz

In today’s world, production is the name of the game. We are all in business to make money. In the Quarrying and Mining industry the same holds true. The primary goal is to develop the best drilling and blasting program available to maintain uniform fragmentation to maximize production. Also we want to maintain drilling and blasting costs and minimize escalators. This paper is intended to discuss ways for all parties (quarry’s, blast service and drill companies) to attain this through understanding what can be done to help blasthole drilling and production. Blast designs and seminar’s emphasize the accuracy of drilling to produce better fragmentation. Blast design must also include basic concepts in the drilling process. The type of drill to be used for example whether it is a crawler or truck mount, top hammer or down the hole is important. Quarry operators have a role to play as well. They hold the key to the production of drilling. What the customer does or does not do has a direct effect financially to the drilling. The phrase of pay me now or pay me latter comes to mind. This paper will explore the detail of planning that is required by the quarry and/or blast service companies before a single hole is drilled. The drill must be able to meet the production need of the operation. The type of drill available and what can and cannot be done. The drill cost must be competitive. This paper will touch on comparison drill costs from 1967 to 1999.

Jan 1, 2000

By Mark H. Balfe

Over the last decade, Fenway Park has undergone annual improvements to modernize the facility for players and fans. These renovations include the Monster Seats, the Right Field Roof expansion, a new pavilion behind home plate, expansion of the Red Sox clubhouse, additional roof seating, and concourse improvements. Retrofitting the historic ballpark to bring it up to current standards required installation of foundations to support the new structural loads for each of the alteration projects. This required evaluation of existing conditions, and in many cases augmentation of the foundations at existing columns to accommodate the structural changes to the park. New foundations, generally consisting of drilled-in micropiles, were installed in numerous configurations and conditions. Since 2003, a total of 215 drilled-in micropiles have been installed to augment various columns around the park. The micropiles range in capacity between 40 and 70 tons and are installed through Fill and Organic Soils and embedded into the dense Glaciofluvial Sand and Gravel layer. Issues and learning related to the foundation augmentation include schedule constraints (work is typically conducted during the off-season and schedule is very aggressive), encountering old/abandoned utilities or foundations, ventilation of equipment, and management of spoils during micropile installation.

Jan 1, 2011

By Fookes R. A, Gardner K. J, Gravitis V. L, Watt J. S, Steffner E. J

Two radioisotope techniques suitable for the rapid laboratory determination of the ash content of coal have been tested ou unwashed coal samples from four Australian coal seams. In one techniqne, measurements of backscattered 238Pu L X-rays and iron K X-rays from finely ground coal samples have been combined to determine ash content in uuwashed coals to ±0.5 weight per ce111 ash (ls) for three seams and 0.9 weight per cent ash for the fourth.The second technique, which involves measurements of the transmission by the coal of narrow beams of 241Am 60 keV and 123Ba 356 keV ? rays, requires less sample preparat ion. The ash was determined to within the range of 0.8 to 2.6 weight per cent for the four seams (unwashed coal). For washed coals, errors are expected to be < ±0.5 weight per cent ash.

Jan 1, 1982

By Dilip I. Patel, Jesus Schabib, W. Allen Mawr, Daniel A. Louis

East Side Access (ESA) will extend Long Island Rail Road into midtown Manhattan via 11 km of tunnels, a new terminal station and associated rail support facilities. The hard-rock tunneling in Manhattan will traverse under Park Avenue and some of the most historically and commercially significant real estate in the world. The soft-ground tunneling in Queens will traverse beneath Amtrak’s Sunnyside Yard and the Harold Inter locking, the busiest rail interlocking in North America. This paper details ESA’s program-wide geo-instrumentation monitoring system for obtaining, processing and presenting all geotechnical monitoring data. Data streams will be real-time, such as from automated total stations, and manually read, such as from optical survey instruments and handheld data loggers. All data will be input into a web-based Geo-Instrumentation Data Management System, which will be accessible to project stake holders via ESA’s intranet or via the Internet using remote access controls.

Jan 1, 2007

By Mike Amick

As virgin coal reserves dwindle, more and more mines are being opened in areas with previous mining. As addressed in this conference before, there are solutions available for designing mines extracting coal from reserves with known underground workings above or below the target seam. Often times, however, mining begins with limited knowledge of the underground workings. Even with careful planning, the proposed design has limited success because the ?facts? as presented during planning turn out not to be as accurate as one would like. At National Coal?s Mine #14, mining the Walnut Mountain seam, after driving the main entries in some 34 crosscuts, it was found during routine mine examinations that the pillars had separated from the roof in a few areas of the mains. Immediate roof conditions proved to be sound but questions arose concerning the stability of the main roof and floor. Core tests were done to better determine the rock strengths and characteristics. The paper presents the ideology used to tackle the effects of mining over old works in an operating coal mine. This paper discusses the analysis of the symptoms observed and the steps taken to ensure that this pillar separation was caused by the underlying old workings and that the separation was expected and controllable.

Jan 1, 2009

By PHILIP N. MOORE

THE development of the power of the Tennessee River at Muscle Shoals has become a matter of political interest as well as engineering possibility. The controversy over it has been so active that the facts have been obscured, the possibilities exaggerated. Although the members of the American Institute of Mining & Metallurgical Engineers are not generally specialists in hydroelectric development, those who visited Muscle Shoals in October, following the Birmingham meeting of the Institute, were interested, and many of them surprised to learn the actual conditions. These have long been familiar to those who have studied the matter through the reports of the U. S. Engineers on the subject. The approved plan contemplates three dams-No. 1, a low dam close to the City of Florence, planned in the interests of navigation, since the construction of the other dams has rendered impossible the use of the river without it. No. 2-named the Wilson Dam is now under construction. Concerning it political argumentation has waged. No. 3 Dam-much smaller, is planned to be erected several miles above No. 2.

Jan 1, 1925

By Randy R. Huberty

Although originally designed with deep foundations consisting of all driven steel H piles and drilled caissons, a unique application of Augered Cast-in-Place (ACIP) piles as an alternate design resulted in a significant cost savings for the Midfield Terminal Project at the Pittsburgh International Airport. The project was enormous in scope covering an area two miles long by one mile wide, with changes in elevation of over 200 ft. The varying geology combined with the large amounts of fill required resulted in a complex set of geotechnical design parameters that had to be evaluated through both load testing and analyses. A total of almost 400,000 lineal feet of ACIP piles were installed for this project.

Jan 1, 2001

Radioisotope x-ray methods for the on-stream determination of copper, lead, and zinc in mineral product slurries were developed, and were successfully tested at the plant of Cobar Mines Pty. Ltd.The tests were made in three stages. Measurements to determine the precision of analysis were made initially on briquettes of the mineral products. The effect of slurry solids content variations was then determined by measurements on the mineral products in a recirculating slurry loop. The radioisotope analyser was finally tested in a series of on-stream measurements in the plant.Copper, lead, and zinc in flotation feed and in copper concentrate were determined to a precision ranging between 1·4 and 15 per cent of the mean element concentration in the slurry solids. These precisions are within limits required for plant control purposes at Cobar.

Jan 1, 1971