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IN this paper it is proposed to present certain features of operating practice at the Port Pirie works of The Broken Hill Associated Smelters Proprietary Limited, in the smelting in a blast furnace of lead ores carrying a high concentration of zinc.The subject matter selected for presentation is:(i) The effect of zinc on lead blast-furnace operations, together with an outline of the methods adopted in actual practice in dealing with the zinc problem.(2) Development of the height of tuyere above the bottom of the jacket, and the extension of the tapping interval and the combined effect of both factors upon the lead content of blast furnace slag.It will later be seen that one phase of the investigation carried out in connection with the effect of zinc on blast-furnace operations was largely responsible for the decision to increase to a marked degree the height of the tuyere above the bottom of the jacket.Due to this interdependence, it has been considered advisable to deal with the two features above mentioned.The high concentration of zinc in the lead-bearing materials smelted at Port Pirie has brought with it those troubles which are associated with zinc in the smelting operation.In the early stages of the history of The Broken Hill Associated Smelters Pty. Ltd. the trend towards increasing cost for labour, fuel, and stores, etc., rendered it necessary to increase the lead content of the charge, and reduce to a minimum the quantity of barren flux used.

Jan 1, 1931

By H. A. Doerner

"The pure mineral chromite, FeO.Cr203, consists of ferrous and chromic oxides, chemically united in equal molecular proportions. Unfortunately, pure chromite as defined above appears to be a rare exception. In most chrome ores the mineral may be considered a combination of spinel, MgO.Al203, and chromite, with the latter predominating. The ratios between the four common constituents Fe0, Mg0, Cr203 and A203 vary greatly, and other minor constituents such as TiO2 and. Fe203 may also be present.In the mechanical concentration of chromite ores the maximum grade of concentrates that can be produced is thus limited by the composition of the chrome minerals present. Pure chromite contains 68 per cent Cr203, but the Cr203 content of the chrome minerals in commercial ores varies between 45 and 60 per cent and the average is not far from 55 per cent.Chromite is usually associated with serpentine. Other silicates, quartz, dolomite, magnetite, ilmenite and other iron Minerals are frequently present.The amenability of a chrome ore to concentration, depends upon the kind and amount of the various gangue minerals present and the amount .of crushing necessary to separate the chromite from them.A relatively small amount of chrome ore is concentrated by milling. In most cases the mine product is simply hand-sorted. Such chrome deposits as are known in the United. States can not be worked in this way on account of one or both of the following conditions: High cost of labor and finely disseminated impurities. There are, however, several deposits in the United States, Canada, and Alaska which may be able to compete with imported or by efficiently utilizing modern ore-dressing and milling methods."

Nov 1, 1930

By Dermot Winters

The Surface Mining Control and Reclamation Act (SMCRA, or the Act) was enacted on August 3, 1977. The Act was written, in part, to put an end to uneven environmental standards and to establish minimum national standards. Certainly, one of the motivating factors for passage of the Act was the success of the Federal Coal Mining Health and Safety Act of 1969 in reducing deaths and injuries in the coal industry nationwide. Section 516 (b) (1) of the Act requires *that subsidence be prevented from causing material damage to the extent technologically and economically feasible except in those instances where the mining technology requires planned subsidence in a predictable and controlled manner. Section 516 (c) of the Act authorizes the regulatory authority to suspend underground mining if there is imminent danger to inhabitants of urbanized areas, cities, towns, and communities. On December 13, 1977, the interim program, which applies a portion of the performance standards of the Act, was promulgated. Then on September 18, 1978, the proposed permanent program was published for public comment. Finally, on March 13, 1979, the final permanent program was promulgated and the States were given a period of time to submit their programs for approval.

Jan 1, 1986

By Hamid Maleki

A comprehensive study consisting of stress determinations, core logging, laboratory testing, and numerical analyses was conducted to investigate the cause and potential alternatives to the coal bump conditions that developed in the Second North Panel of the Little Dove mine near Buntington, Utah. Roof rock characteristics were such that a cave did not develop above this 420 ft wide panel. After 700 ft of pillar retreat, severe coal bump conditions developed during pillar mining. The coal bump conditions resulted from excessive pillar stress which was caused by load transfer from the extracted, noncaving, portion of the panel. Site specific data and numerical modeling techniques were used to back-analyze the bump prone condition. This back- analysis lead to the identification of critical stress, closure, and energy release levels. These critical levels were then used to evaluate alternative pillar mining sequences in the hope that the potential for coal bumps could be reduced. It was found that while alternative sequences offered some potential improvement over the pillar mining sequence used in the mine, alternative pillar mining sequences would not significantly reduce the potential for bumps. For the roof characteristics at this mine, coal bumps are best avoided by developing narrow panels or significantly wider panels, which incorporate properly sized barrier pillars. Narrow panels, on the order of 300 ft, would not cave, but panel pillar stresses and the potential for umps would be moderated by the reduced r' panel width. Wider panels, of approximately 650 ft, would allow a cave to develop, also reducing panel pillar stresses and coal bump potential.

Jan 1, 1987

By Andréa Lagacé

"The milling of sulphide ores inherently generates “thiosalts”, a series of partially oxidized sulphur oxyanions (S2O3 2-, S3O6 2-, S4O6 2- etc.), which make control of effluent treatment systems difficult because their natural oxidation produces acid with the potential to lower the pH within the treatment system and/or receiving environment.At the Xstrata Copper Kidd Metallurgical Site, thiosalt oxidation in the Tailings Management Area continues after buffer storage Ponds A and C where lime is added to precipitate metals and elevate the pH to within the required range for discharge. If the additional acidity generated during the continued process of thiosalt oxidation is not neutralized there is a risk that the final effluent will be non-compliant with regulated standards.To mitigate this risk, in 2007 a full scale pilot trial was conducted with hydrogen peroxide in order to force the complete oxidation of thiosalts prior to the lime treatment stations. This method of chemical oxidation had been shown to be effective at Xstrata Zinc’s Brunswick Mine. The pilot results indicated that a maximum of 50% of the stoichiometric quantity of hydrogen peroxide is required to reduce the thiosalt concentration in the No. 2 thickener overflow stream (feed to buffer storage Ponds A and C) to less than detection (10 mg/L); however, treatment was only effective in the presence of a 20 mg/L iron (Fe) catalyst. Since the hydrogen peroxide addition point at the No. 2 tailings thickener overflow typically contains <1 mg/L total Fe, a second reagent, ferric sulphate, was used to increase the total Fe concentration to the required level. This paper describes the set-up and results of the pilot trial which were used in the design of the full-scale plant.INTRODUCTIONTailings Management Area OverviewXstrata Copper’s Kidd Metallurgical Site, located in Timmins, Ontario, is an integrated metal refining facility producing copper, zinc, cadmium, indium, liquid sulfur dioxide, and sulfuric acid from third party custom feeds, and mineral concentrates recovered from its 7,800 tonne per day mill."

Jan 1, 2010

By David B. George

Kennecott Utah Copper adopted Outokumpu Flash Smelting and Kennecott-Outokumpu Flash Converting in 1995, a process based on granulating high grade copper matte. While nickel mattes and very small quantities of copper matte had been commercially granulated for years, no large scale copper matte granulation system had been built. This paper summarizes the history and benefits of copper matte granulation, the Kennecott design basis, the successful operation for over 10 years and potential problems inherent in some matte granulation approaches.

Jan 1, 2006

By N. P. Kripakov

Results of a complex three-seam interaction analysis in a western U.S. coal mine are presented. The physical situation simulated by the models represents the development of a set of entries underneath two previously mined seams with all three seams in proximity to each other. The layout and the geometry of the remnant pillars in the upper seams were nonuniform and not always directly superimposed over each other, creating a very challenging modeling problem. The U.S. Bureau of Mines&apos; MULSIM/PC computer code was upgraded and enhanced to perform the required three-seam interaction calculations. Analysis was limited to simple linear-elastic assumptions as only peak stresses were required. Results clearly indicated that stress concentrations in the lower seam increased approximately 100 percent when compared to cases simulating no extraction in the two upper seams. These stress concentrations generally occurred in zones directly below points of highest abutment pressures in the upper seams. Overall, the model results compared favorably with actual documented observed behavior where roof failures were known to have occurred.

Jan 1, 1996

By A. M. Tunstall

Aspects of blast vibrations, damage mechanisms and the influence of rock quality on damage severity are reviewed and results presented from a monitoring programme in which the rock mass rating for six tunnels was determined. The peak particle velocity induced in the tunnels during open-pit blasting was measured and the tunnels were inspected visually for fresh damage after each blast. The results suggest that the quality of rock in which an excavation is situated has an influence on the level of ground vibration to which it can be subjected without sustaining damage. This means that the use of a single limiting value of peak particle velocity, as in the blast damage criteria for residential structures, is not ideal and may result in damage to excavations in poorer-quality rock masses

Jun 19, 1905

"The link between ore texture and mineral liberation has previously been established at a microscopic scale. To construct ore texture models that can be used in mining applications requires this relationship to be retained at a significantly larger scale. This is initially dealt with by finding a basic set of microtextures that form the elements of the ore textures at the next larger mesoscopic scale, simulating these mesotextures at a fine scale, then changing the support of the mesotexture simulations to generate the expected mining block/stope mesotexture distributions. Thus, a mutually exclusive and exhaustive set of spatially locatable mesotextures can be used to fully characterize the metallurgical properties of in situ material.A method that generates expected distributions of mesotextures for any mining block size or shape is proposed, and includes: (1) characterizing the spatial correlation of the set of mesotextures with a single covariance function; (2) generating multiple simulations of mesotextures at a fine scale; and (3) using the simulations at a fine scale to generate the expected mining block/stope mesotexture distributions. A case study, using the George Fisher sediment-hosted base metal deposit in Queensland Queensland, Australia, is developed to demonstrate the proposed methodology as well as show the inadequacy of off-the-shelf approaches.Mining-scale texture models can be used to improve the in situ discrimination of ore from waste by exploiting the joint spatial variability of grades and textures to quantify the expected metal recovery of in situ material, then calculate local marginal cut-off grades. An artificial case study is presented to demonstrate the changes in ore/waste selection when considering ore texture models compared to constant metal recoveries."

Jan 1, 2005

By C. Crussard, R. Tamhankar

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 accord-ing to established criteria for technical merit, accuracy, originality, and presentation. STAFF: Editor, Gerhurd Derge Carnegie Institute of Technology Schenley Park Pittsburgh 13, Pa. Editorial Assistant, M. A. Redmerski Staff Coordinator, James J. Burke THE METALLURGICAL SOCIETY: W. R. Hibbard, Jr., President; J. C. Kinnear, Jr., Past-President; John Chiprnan, Vice President; T. D. Jones, Treasurer; R. W. Shearman, Secretary. PUBLICATIONS COMMITTEE OF THE METALLURGICAL SOCIETY: A. W. Thornton, Chairman; Dennis Carney, John Chip-man, J. C. Fulton, J. H. Hollomon, H. H. Kellogg, A. E. Lee, R. Maddin, J. D. Sullivan, and D. Swan. Review and selection of manuscripts is under the supervision of the following Publications Committees: Extractive Metallurgy Division: T. B. 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. Backofen, R. W. Balluffi, J. H. Bechtold, M. B. Bever, R. S. Busk, C. G. Goetzel, Paul Gordon, C. D. Graham, .Jr., Robert F. Hehemonn, R. I. Jaffee, F. E. Jaumot, Jr., Irving R. Kramer, A. J. Lena, Harold Margolin, C. J. McHorgue, Russell A. Meussner, J. B. Newkirk, H. W. Paxton, G. E. Pellissier, I. S. Servi, Alan 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. Telephone: PEnnsylvania 6-9220. Subscription $20 per year for non-AIME members in United States and North, South, and Central America; $25, foreign; $5 for AIME members. Single copies, $4.00, 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 Institute of Mining, Metallurgical, and Petroleum Engineers, Inc. . . . Registered cable address, AIME New York ... Indexed in Engineering Index, Industrial Arts Index, and Chemical Abstracts... Second class postage paid at New Yark, N. Y., and Ann Arbor, Mich. Volume 212, Number 6.

Jan 1, 1959

By G. R. Addie

"In February, 1975, the President of Georgia Iron Works Company, Mr. Tom Hagler decided to build a new hydraulic laboratory to water performance test all of the companies' centrifugal slurry pumps.Equipment procurement started in March, 1975, by ordering of a mini computer data acquisition system.Work commenced on the lab in July, 1976, by erection of a Butler Building and the laying down of a 20,000 gallon concrete sump.By late October, a facility compromising two water test loops of 8"" and 18"" pipe diameter was in operation carrying out head quantity and suction performance tests on pumps up to 16"" in size.In August of the following year, an 8"" diameter pipe slurry loop was installed to enable pipe friction and deposition velocity of a slurry to be measured in an 8"" inside diameter pipe.With the encouragement of Reserve Mining in Minnesota and IMCC in Florida, this was followed in March, 1978, by the addition of over 300 feet of 18"" diameter pipe to make up an 18"" diameter pipe slurry system complete with head loss and deposition velocity observation sections.The office and shop areas of the lab were again expanded in April, 1978, to provide further expansion to the test sections and staff facilities."

Jan 1, 1980

By David G. Almond

"Economies of scale and the variable characteristics of many large ore deposits have resulted in grinding installations having large SAG mills fitted with variable speed drives. Problems associated with effective operation of this equipment has created the need for better operator knowledge of mill load behavior and the need for new instrumentation capable of providing accurate information about load movement and composition. This paper discusses two performance enhancing instruments available to address these needs.INTRODUCTIONThe economic demands of new mining projects has resulted in increased equipment sizes and this is particularly evident in milling where there are now many SAG mills operating in the range of 28’ – 40’ diameter with installed powers of 8 – 22 MW. These mills are designed to process very high capacities of ore daily2 and the variable characteristics of many of the deposits mined results in the need to vary the mill speed during processing to cater for the changes in ore hardness. Mill speed changes often result in operational problems associated with high-energy impacts striking the mill liners reducing energy efficiency as well as degrading the grinding media through breakage, accelerating liner wear and in extreme cases even breaking liners. These operational problems have given rise to the need to have instruments aimed at providing operators with accurate information in real time about the load composition and movement within SAG mills.The original concepts for operating SAG mills were derived from past experience of operation of conventional fixed speed ball mills. However, the relatively stable conditions that applies with fixed speed and constant ball charge in ball mills supports theoretical approaches to the grinding process based on energy calculations such as Bond’s Work Index concept. Later a set of parameters Si and Bij were used for describing load kinetics, but all of these methods neglect the details of load movement and how the energy is actually used inside of the mill. It is now commonly accepted as a basic rule that SAG mills grind by impact whilst ball mills grind by attrition and consequently SAG mills are designed and operated to generate a large amount of impacts by the cataracting load without paying sufficient attention to where these impacts are actually occurring. Many mills are operated on the basis that as long as the mill is consuming the expected power there is little attention given to the class of bodies using this energy and this often results in the inefficient use of energy."

Jan 1, 2005

The objective of this study was two-fold: 1. To perform a world literature search pertinent to the analysis, selection and design of hoisting systems and their components and to codify the search into a literature compendium. The search resulted in a technical data file of over 1500 hard copy items. The compendium index was also suitable for establishing a comprehensive computer-loaded data base on the subject. 2. To develop a comprehensive system of guidelines to cover salient aspects of analysis, selection and design of electrical, mechanical and structural components of a hoisting system with a view to establish parameters for maximum safety and efficiency of operation, installation and revision of the system. 3. (a) The system design of hydrostatic drives for mine hoists, usually of special nature, is considered along with oil hydraulic component selection suitable for the application; (b) The criteria for head frames of steel and/or concrete are developed with full consideration of all operating and environmental conditions.

Jan 1, 1988

By Robert J. Dompe

The objective of this program was to develop a cost effective microprocessor-based electronic image sensor system for monitoring pit slope displacement to detect and/ or predict impending slope failure in surface mines. A background study and data analysis yielded a performance specification for candidate Video Slope Monitoring Systems. A design concept was developed based on using a pair of solid state video cameras located on precision pointing assemblies. The digital images from the cameras are compared and, using electronic triangulation, slope topology is calculated. The current and past locations of operator selected features are compared to determine pit slope displacement. A proof-of-concept test was performed using a laboratory model of a pit slope. Based on the successful results of that testing it is recommended that an in-mine evaluation be performed using a full-scale prototype Video Slope Monitoring System.

Jan 1, 1982

By Melford H. Salsbury

The maximum net return from the sale of ores and concentrates of gold, silver, copper, lead, and zinc accrues to the producer when these mine products are marketed to the best advantage. Data are presented that the producer, especially the small mine operator, can use to survey available markets and make a preliminary estimate of the net return to be expected from an ore, on the basis of typical mill, smelter, and freight schedules. A review of the industry is presented by States in which recent production statistics are given, marketing facilities are discussed, and locations of principal mining districts, custom mills, and smelters are shown. Explanations of treatment processes, ore types, treatment charges, payments for metals, and deductions are given. Published rail and truck freight rates for mine products, based on marketing patterns developed over many years, are listed and explained.

Jan 1, 1964

By E. K. Stanek

The field tests involved ten coal mines in which transients were initiated on the dc system from which the parameters of the dc mine electrical power system could be determined. The data processing involved the use of a Fourier Analyzer to filter noise and fit an exponential curve to the field waveforms. From this data analysis it was possible to find the dc system resistance, inductance and time constant. The survey of nationally recognized laboratories was conducted to establish that the recommended test criteria were practical. The development of test criteria for dc fuses used in mines was based on the measurement of parameters in the field, the survey of testing laboratories, literature searches, laboratory test, etc. A computer program was written to analytically predict the parameters measured in the field. This approach has limitations but reasonable agreement with field results was obtained. A brief laboratory testing program was carried out to verify the practicality of the recommended criteria and establish the accuracy of the conclusions concerning dc fuse performance.

Jan 1, 1984

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 Paul L. Michael

Roof warring signals from eleven underground coal mines (principally in the Pittsburgh seam) were studied and analyzed. The character of individual acoustic warning signals is shown to be dependent on spectral distribution of energy. Reverberation tires (pulse decay rates) were found to be usually between 0.1 and 0.5 seconds. Listening tests were conducted to assess the miner&apos;s ability to discriminate speech and roof talk signals in noise and in quiet, with and without ear protectors and with various levels of hearing loss. The ability to detect roof talk is shown to be generally degraded while wearing car protection in quiet, although, if car protectors are worn only when required by high noise levels, the ability to detect roof talk will be preserved at its maximum.

Jan 1, 1972

By William R. Archibald

This report presents the results of a program demonstrating the technical and economic feasibility of hydraulic borehole mining of uraniferous sandstone. This mining technique involves the drilling of a borehole from the surface down into the ore body. A borehole mining tool consisting of a high-pressure cutting jet and a slurry jet pump is lowered down the borehole. Water from the high-pressure cutting jet cuts into the sandstone formation generating a water-sand slurry which flows to the slurry jet pump and is pumped to the surface. The cutting jet is rotated and moved up and down from the surface, thereby generating a cavity in the formation. When the cavity size reaches a point beyond the effective radius of the cutting jet, the mining tool is moved to an adjacent borehole and the process is started again. This program was carried out in four phases. Phase I included modifications to the borehole mining system (built and tested under a previous contract, No. H0252007, for the mining of coal) and factory tests of the jetting system. Phase II covered the field tests and a public demonstration. Phase III involved nozzle and equipment modifications and factory tests. Field testing continued under Phase IV along with an evaluation of this method. The field tests were conducted successfully on Rocky Mountain Energy Company&apos;s Nine Mile Lake property near Casper, Wyoming. Results indicate that; hydraulic borehole mining of uranium is technically feasible (300 tons of uraniferous sandstone were mined from a depth of 90 ft) and the hydraulic borehole method is economically attractive. However, additional testing is required to clearly define the economic feasibility.

Jan 1, 1978

Two coal seams were selected and the conceptual designs were based on the geological and physical conditions typical of these seams. As a result of the screening process presented below, the two coal seams selected were the Lower Kittanning Seam in central Cambria County, Pennsylvania and the Pittsburgh Seam in northwestern West Virginia and southwestern Pennsylvania. SELECTION PROCESS FIRST SCREENING OF LONGWALL OPERATIONS The list of longwall operations prepared in Phase I and included in the Phase I report, was used as the basis for a first screening. From this list it was determined which longwall operations were not in the Appalachian coal fields and not in a coal seam of the thickness range of 42 to 72 inches. The first screening eliminated 30 of the listed operations, leaving 48.

Jan 1, 1976