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By Bradford F. Townsend, Marc R. Kritzer, Michael F. Roach, Dennis Ofiara

All Rights Reserved. Printed in the United States of America. Information contained in this work has been obtained by SME, Inc. from sources believed to be reliable. However, neither SME nor its authors guarantee the accuracy or completeness of any information published herein, and neither SME nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SME and its authors are supplying information but are not attempting to render engineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Any statement or views presented here are those of the authors and are not necessarily those of SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2008

Nowadays, technology has improved to extract dimensional stone blocks at quarry sites and also to process these at processing plants for making slabs and tiles. In the process of quarrying and processing, performance evaluation of machinery is very important to achieve optimum output at minimum cost with improved technology. Cost analysis of improved technology includes parameters such as manpower, energy consumption, tool consumption, depreciation, maintenance and also others. The chainsaw machine with long boom and rail in marble quarries and multi-diamond wire saw machine for slab making from granite blocks at processing plants have recently been introduced in India. Thus, a study was carried out under a research project on these machines to assess their suitability. In this paper, performance evaluation and cost analysis of chainsaw and multi-diamond wire saw have been carried out with existing machines on the basis of research findings.

Dec 6, 2010

The 22nd Annual American Mining Hall of Fame Awards Banquet sponsored by the Mining Foundation of the Southwest will be held at the Westin La Paloma in Tucson, AZ on Saturday, Dec. 4, 2004. This year’s inductee, guest of honor and featured speaker at the banquet will be J. Steven Whisler, chairman and chief executive officer of Phelps Dodge. Whisler is also a director of Phelps Dodge, Burlington Northern Santa Fe, America West Holdings, the National Mining Association, the International Copper Association and the Copper Development Association.

Jan 1, 2004

By F. P. Haver

The Federal Bureau of Mines developed a 10,000-ampere cell to determine the economic feasibility of producing high-purity electrolytic titanium from mill scrap or offgrade sponge. Operating variables were investigated, matetial handling procedures were established, and the cost of electrorefining titanium was determined. The prototype cell produced premium-grade metal (<100 Brinell hardness number (B.h.n.)) from very impure Kroll sponge at a processing cost of less than $0.60 per pound. Refined metal was deposited at the cathode in the form of coarse (85 percent plus 34-mesh), hexagonal crystals of a titanium when the cell was operated an 850° C. A cathode current density of 1,000 amperes per square foot and a molten sodium chloride electrolyte containing approximately 5 percent by weight of soluble titanium were used. In continuous operation, at the optimum number of ampere-hours, (40,000), the current efficiency averaged slightly less than 60 percent. It was possible to supply large enough amounts of electric current for electrolysis to maintain the temperature of the bath, thus reducing overall power consumption to less than 5 kilowatt-hours per pound of metal refined.

Jan 1, 1961

The contract for the Water Jet Chock Mounted Miner Feasibility Study was awarded to FMC Corporation&apos;s Advanced Products Division on 18 November, 1974. The program was divided into four phases as follows: ? Phase I - Planning ? Phase II - Conceptual Design ? Phase III - Budgetary Cost Estimate and Economic Feasibility Study ? Phase IV - Final Report During Phase I, which lasted 1 month, most of the necessary information and data for the conduct of Phase II was obtained. To accomplish this, arrangements were made for personal visits to the University of Missouri at Rolla, Illinois Institute of Technology Research Institute, USBM TCMRC, Alpine Equipment Co., Mining Progress, Inc. and Eastern Associated Coal Corporation&apos;s Harris No. 1 Mine. Also, a list of manufacturers of high pressure equipment was compiled to be contacted during Phase II. Finally, the objectives to be accomplished during Phase II were outlined. The Phase I Report was submitted on 23 December, 1974. At the beginning of Phase II, personal visits were made to the research centers and firms mentioned above. Later an additional visit was made to the Harris Mine, and to the Pittsburgh Mining Research Center at Brucetun to observe a test of a water jet mounted on an Alpine Mining Machine. Equipment manufacturers of high pressure components such as hoses, tubing, valves, pumps, and intensifiers were contacted to obtain item performance data, availability, and cost.

Jan 1, 1975

By F. Dai

Granitic rocks usually exhibit strongly anisotropy due to pre-existing microcracks induced by geologic loadings. The understanding of the rock anisotropy in mechanical properties such as tensile strength is critical to quarrying and stabilization of underground structures. In this paper, Brazilian tests are conducted in combination with MTS material testing machine and split Hopkinson pressure bar (SHPB) system to measure both static and dynamic tensile strength of anisotropic Barre granite. Samples are cored and labeled using the three principle anisotropic directions of Barre granite (BG). These directions are also chosen as the loading directions for the Brazilian discs. For dynamic tests, pulse shaping technique is used to achieve dynamic equilibrium in the samples during the test. Finite Element Method is implemented to formulate equations that relate the failure load to the material tensile strength employing a orthotropic model for Barre granite. For samples in the same orientation group, the tensile strength shows clear loading rate sensitivity. The tensile strengths exhibit clear anisotropy under static loading; while less anisotropy under dynamic loading. The tensile strength anisotropy of Barre granite is interpreted as interactions of the pre-existing microcracks.

May 1, 2009

Three complete connector assemblies and six separate contacts were submitted to a series of tests to establish the connectors permissibility and compliance with U. S. Bureau of Mines research Contract #H 0110423 D.C. portion. Test Procedure TPC-0118 was coordinated, and the test plan approved by the Bureau as fully complying with the intent of the contract for the direct current connectors. The components and connector assemblies have been demonstrated in testing that they meet or exceed all the requirements of the test procedure.

Jan 1, 1974

By D. Imeson, T. Grammatikopoulos, G. Pearse, M. Aghamirian, C. Mohns

"Spodumene mineral is a source of lithium for lithium ion batteries. Thus, the production of a spodumene concentrate with an approximate grade of 6% Li2O is targeted. Traditionally, spodumene is concentrated by froth flotation using fatty acid as the collector. Amine collector can also be used to float mica ahead of spodumene as required or feldspar from the spodumene tailings. Slimes have a negative effect on spodumene flotation and they are commonly separated by scrubbing and de-sliming prior to spodumene flotation. The main losses in spodumene flotation typically occur in cyclone overflow, scrubbing slimes, spodumene flotation tailings and mica concentrate. In recent years, dense media separation (DMS) is the main concentrating process in Australian spodumene operations. In these operations, DMS is efficient at generating coarse grain concentrates and rejecting large portions of silicate gangue, thereby directly reducing the milling cost. The ore should be crushed to 3/8” or coarser while further crushing is possibly necessary on the middling particles to scalp further spodumene. The DMS feed should be classified to remove fines (typically -0.5 mm particles). The final middlings and undersize fractions could then be processed by flotation. The main requirement in DMS operations is to have good spodumene liberation at relatively large grain size. This paper reviews the most significant DMS and flotation parameters in spodumene beneficiation. The treatments of different minerals in the spodumene ore are also addressed.INTRODUCTION A number of laboratory/pilot plant programs have been recently conducted at the SGS Lakefield site, sponsored by different clients. The main objective has been to develop a process flowsheet to generate a spodumene concentrate containing 6.0% or higher Li2O (~75% spodumene) suitable for producing lithium carbonate by a hydrometallurgical process. Depending on spodumene liberation size, dense media separation (DMS) can be an attractive option to produce a final high grade concentrate and to reduce the mass to be treated in the flotation circuit. In such a case, crushing would typically be performed in stages, with DMS separation to recover a spodumene concentrate and reject gangue minerals following each stage. DMS middlings and -0.5 mm fines can be processed by flotation to further recover spodumene. In the flotation process, coarse stage grinding minimizes the grinding cost and formation of slimes. In the majority of cases, a grind size (K80) of approximately 200 microns is sufficient for flotation. After primary grinding, mica, if present in an appreciable amount, should be floated to minimize interference with spodumene flotation. Desliming after scrubbing and high density conditioning are the key process operations prior to spodumene flotation. Spodumene can then be floated from silicate gangue minerals with a fatty acid or a mixture of fatty acid and petroleum sulfonate at slightly alkaline pH. Subsequently, feldspars can then be floated from the spodumene tailings."

Jan 1, 2012

By J. M. Uys, T. B. King

WalSH, Chipman, King, and rant&apos; have measured the water content (as hydrogen) of actual steel-making slags. An average water content of 290 ppm was found for basic open-hearth tapping slags and 114 ppm for acid open-hearth slags. Upon equilibration of these slags at 1550°C with a 25 pct H20-75 pct Nz atmosphere, the water content increased to about 410 and 300 ppm for the basic and acid slags, respectively. Walsh et al. concluded that an acid slag was thus relatively far removed from equilibrium, and that basic slags showed a closer approach to equilibrium, with the water vapor in the furnace atmosphere. Herasymenko2 contended that these conclusions were unjustified, as the oxygen pressure used in the equilibration experiments, ;bout 5 x X atm, was quite different from that found in the furnace. Consequently, during the experiments the slag composition would have changed due to oxidation of ferrous iron. As an extension of Walsh&apos;s work and to attempt to clarify this matter, the solubility of water in a basic open-hearth slag was measured as a function of oxygen pressure. Similar measurements were also made on synthetic silicates in the "Fe0"-Fe203-SiO, system. The experimental technique has been described previously by Walsh et a1.l and Uys and King.3 Samples of the basic open-hearth finishing slag, contained in 10-cc platinum crucibles, were equilibrated at 1550°C with atmospheres of different oxygen pressure but constant water-vapor pressure, Ph~o = 0.192 atm. Calculations, as well as measurements, indicate that this figure approximates the water pressure of the combustion gases in a steam-atomized, oil-fired open hearth. Oxygen pressures in the open hearth can vary from 10"2 atm in the combustion gases to between l0-&apos; and 10" atm in the steel bath. The former figure depends on the combustion practice and the latter on the carbon content and temperature of the bath. The oxygen pressure of the slag should lie somewhere between these extremes and is expected to be closer to that of the steel bath than that of the combustion gases. Oxygen pressures were therefore varied between 10" and 6 x l0 atm. At the lowest pressure the slag "puffed up" when quenched (indicating possible loss of water) so experiments were not conducted at lower oxygen pressures. The results are shown in Fig. 1, which includes the water content of the slag "as sampled". The results show that the water content of the slag increased appreciably on equilibration with water vapor at 0.192 atm pressure and that the water solubility apparently decreases with increased oxygen pressure. The solubilities found are comparable to those of the Li20-Ca0-Si02 system.3 Work with synthetic slags in the "Fe0"-Fe203-SiOz system was performed at 1500" C, with Ph20 = 0.192 atrn and for oxygen pressures varying between 10"2 and 10-lo atm. Samples for chemical analysis were prepared as described by Larson.4 The results are shown in Fig. 2. Some low-silica melts tested at low oxygen pressures "puffed up" when quenched and analyzed less than 100 ppm water; these results are not included in Fig. 2. The melts containing 40 mol pct silica also showed a tendency to "puff up" during the quench, when they were tested at the lowest oxygen pressure. These results indicate that, at constant silica content, the solubility of water decreases somewhat with increased oxygen pressure. The effect is, however, small considering the wide range of oxygen pressures studied. Also, at constant oxygen pressure (above about lom5 atm) the solubility increases

Jan 1, 1963

By Ian Holl, Adam Hempstock, Rickardo Welyhorsky, Niel Morrison

"The Victor Diamond Mine is located in the James Bay lowlands, 90 km west of the First Nations village of Attawapiskat. The project was the first of its kind in northern Ontario and was completed approximately 9 months ahead of schedule.The Victor Mine process plant flowsheet was designed to produce a 95 - 98% by weight diamond concentrate. Main processing steps include 3 stages of comminution, dense medium separation and proprietary x-ray technology for final recovery. Reagent consumption for this process is limited to flocculant, for thickening of fine processed kimberlite, and FeSi for the dense medium separation.The commissioning phase of the Victor Project was executed over a period of 6 months and commenced prior to substantial completion of construction. The approach used was to focus on and complete commissioning of the higher risk dense medium separation and recovery systems prior to construction completion of up stream systems.INTRODUCTIONThe development of the Victor Diamond Mine took place over a period of approximately 5 years and had a capital cost of CAD997 million. It was a greenfields project in an undeveloped region of northern Ontario, only accessible by winter road. Figure 1, below, displays the location of the project within Ontario.The main stages of the project included feasibility, environmental permitting, engineering, construction, and commissioning. At the onset of the engineering phase, the mine was scheduled to enter production in October 2008. Through a team effort between AMEC and DeBeers Canada, the schedule was advanced by 6 months towards the goal of project completion in April 2008. Production status was attained in January 2008, approximately 9 months ahead of the original schedule. This paper focuses on the commissioning aspects of the project and includes a less detailed discussion of the engineering stage."

Jan 1, 2010

By L. J. Olivier

The possible closure and subsequent flooding of South Deep Gold Mine?s (SD) neighbouring Randfontein Estates Limited No. 4 Shaft (REL 4) necessitated the construction of five concrete plugs in the connecting tunnels to prevent the ingress of groundwater into REL4 from flooding SD. This paper describes the proposed controlled flooding of REL 4, the planned in-service monitoring of the five plugs and the water barrier between REL 4 and South Deep Mine, and the long-term maintenance of the plugs and rock mass in the immediate vicinity of the plugs.

Jan 1, 2006

By D. N. Ferguson

The separation of certain minerals by electrostatic techniques can be difficult due to their similar electrical conductivity, and any technique to improve this can be useful in certain difficult separation applications. Triboelectric differences between mineral scan result in certain minerals acquiring small positive or negative charges prior to inductive electrostatic separation. By changing the polarity of inductive separation, relative changes in mineral recovery can be observed, which may be beneficial. In this brief study a JKTech mineral liberation analyser (MLA) was used to evaluate the effect of polarity change on selected minerals present in the Richards Bay Minerals deposit, and an approximate triboelectric series based on this behaviour is presented.

Jan 1, 2010

The following Inventory was prepared to provide mineral deposit data to the U.S. Army Corps of Engineers for use in the Resource Development Navigation Study in Alaska. The inventory was prepared using data contained in the U.S. Bureau of Mines Minerals Availability System (MAS) database. The Alaska portion of the database contains Information on over 7,000 mineral locations and deposits throughout the state. When MAS was established In 1975, database entries were originally compiled from literature searches by both Bureau personnel and contractors. Deposit data are obtained/maintained through Information gained from a variety of sources, Including published and unpublished Bureau of Mines reports, records, and files; U.S. Geological Survey (USGS) Bulletins, Professional Papers, and other reports; technical and professional Journals; State and other Federal agency publications; data generated during field examinations; and information obtained from knowledgeable individuals. Because of the size of the data base, many of the data have not been significantly modified since initial entry. Each deposit on the MAS data base has a sequence number of the following form:

Jan 1, 2011

At a regional scale, the Otago Schist has been divided into textural zones, metamorphic zones, structural transposition zones, and terranes and lithologic associations. Each of these subdivisions reveals aspects of the internal structure of the lithologically monotonous Otago Schist but, to date, a map of the schist derived directly from structural data has not been made. In the present study, digitised structural data from the QMAP GIS were used to make a form line map of Schist foliation which, in turn (and using certain non-unique guiding assumptions), was used to construct a provisional foliation thickness map of the Otago Schist. Contours of dominant foliation (Sp) thickness have been drawn from 4 kIn above to 16 km below the reference level of the Caples-Torlesse terrane boundary in the schist structural pile. A recent revision of the Otago Schist textural zone classification has shown that the grain size of metamorphic white micas increases progressively with textural grade. There also appears to be a correlation between schist mica grain size and foliation thickness. Using mica grain size, it may eventually be feasible to establish the vertical structural position of samples in greenschist facies parts of the schist pile to a precision of ¦ 1 km or better, even if they are in inliers or fault-bounded blocks. Foliation thickness and mica grain size are thus potentially useful tools for research and exploration in the Otago Schist in that they assist with structural interpolation and extrapolation. Even at this early stage of application they can be used to provide hitherto unobtainable, semi-quantitative estimates of displacement on Mesozoic and Cenozoic faults and folds. &nbsp;

Jan 1, 2001

By W. Kracht

Frothers are surfactants used in floatation to aid generation of small bubbles. Studying events at the moment of bubble creation is a challenge because of the short time frame. This presentation introduces a novel acoustic approach. The technique has the resolution capable of detecting events that occur within 1-2 ms. The transition from coalescence to non-coalescence is tracked as a function of surfactant concentration and gas rate through the capillary. Results are given for some common flotation frothers and n-alcohols (C4-C8). A stress model is used to give a qualitative explanation to the observed action of frothers on coalescence prevention. Results for salt (sodium chloride) are included for comparison).

Jan 1, 2009

By Abraham Lindo

"Blasting plays a key role in hard rock underground mining. It is by nature a violent and destructiveextraction method designed to economically fragment the rock into a suitable size for it to be loaded and hauled as part of the specific mining process while controlling the amount of damage to the surrounding rock mass."

Jan 1, 2016

By Wilfrid Comeau

This paper deals with the concept of a Quality-Assurance Manual, to the ISO-9001 Level, for quarry blasting in the urban environment. A case history of the incident, which led to its development, is presented in addition to three other case histories. These case histories are related to the potential effectiveness of a well thought-out and applied Quality-Assurance Manual in the conclusions. The basic principle, behind the development of a Q-A manual, is to supply a maximum of quality assurance with a minimum of disturbance to the operation of the quarry. This requires that every intervener in the quarry blasting operations, from management to labourer, be made responsible for the quality of their work. This basic goal can be achieved with a minimum of paper work and added bureaucracy. The manual respects the ISO principle that: Q-A Manuals are not recipe books and should allow for continuing technological developments.

Jan 1, 2003

By Hemang Desai

A damaged outlet pipe beneath Lenihan Dam has restricted reservoir discharges, severely constraining the owner?s groundwater recharge program. The solution, a new outlet pipeline through the dam?s right abutment, includes an approximately12.2-m-deep (40-ft-deep) shaft and 618.7-m-long, 4.3-m-diameter (2,030-ft long, 14-ft-diameter) tunnel mined in Franciscan melange composed of hard blocks of rock and soft clayey matrix. Alternating road header with drill and blast operations and using steel ribs and shotcrete have proven a flexible combination for handling the variable ground conditions. Excavating the shaft and connecting it to the tunnel require lowering the reservoir for five months, during which time careful construction sequencing and use of a tunnel plug eliminate the risk of an uncontrolled discharge.

By R. K. Zipf

The sudden, violent collapse of large areas of room-and-pillar mines poses a special hazard for miners and mine operators. This type of failure, termed a cascading pillar failure, occurs when one pillar in the mine layout fails, transferring its load to neighbouring pillars and causing them to fail in succession. Recent examples of this kind of failure in coal, metal and non-metal mines in the USA are documented. Mining engineers can limit the danger presented by these failures through improved design practice. Whether failure occurs in a slow, non-violent manner or in a rapid, violent manner is governed by the local mine stiffness stability criterion. This is used as a basis for three design approaches to control cascading pillar failure: containment with barrier pillars during pillar splitting; prevention with panel pillars of high width-to-height ratio and small-centre mining; and full extraction by retreat mining

Jun 19, 1905

By P. Zhang

A multiyear, comprehensive study of flotation reagents used in phosphate beneficiation was conducted. The study involved the evaluation of pure fatty acid compounds, comparison of various anionic collectors and testing of iso-acids. Various C12 to C22 fatty acids were tested as Florida phosphate collectors. The saturated fatty acids were found to be very poor collectors when using the standard conditioning procedure, whereas the unsaturated C16 to C22 fatty acids showed fair to good phosphate collecting ability. The C18 fatty acids oleic, impure oleic and linoleic and the C20 eicosenoic acid were shown to be the best phosphate collectors. The best flotation results were obtained using Liqro GA tall oil and oleic acid. Four isostearic/iso oleic acid type fatty acid collectors were compared with a commercial grade oleic acid and with Liqro GA tall oil as phosphate collectors using standard laboratory conditioning and flotation procedures. The most selective collector evaluated was Century 1108, a high isostearic acid-type reagent. However, it was concluded that this excellent-performing reagent was too expensive for commercial use. Overall, the most promising reagent was probably Century MO-5. This collector is essentially an iso-oleic acid/stearic acid mixture (not isostearic acid), and it costs much less. This program laid a sound foundation for developing single collector, all anionic flotation processes.

Jan 1, 2009