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By B. H. Moore

The opportunity to evaluate the pile design procedures used on a major project is an infrequent occurrence. It is even more infrequent that the project involves piles with significant tension and horizontal capacities. This report synopsizes over twenty years of design and construction experience on just such a major pile founded structure. The philosophy governing foundation design procedures is described and discussed. The order and extent of full scale pile testing are evaluated. Principal points in the specifications are established and their effect on construction progress and claims are noted. The report concludes with recommendations for future projects.

Jan 1, 2010

By James L. Ash

This report contains the results of a technical and economic evaluation of conceptual systems for the underground mining, rubblization, and in situ retorting of deep oil shale deposits. Study efforts were first directed towards evaluation of the applicable geology, associated minerals, rock mechanics, in situ retorting, access mining, ventilation, rubblization, safety, and environmental impact factors. Conceptual systems were synthesized and then evaluated against these factors from both a technical and limited economic viewpoint. The results of these evaluations were then analyzed and, based upon this analysis, the following two systems were selected for further study: System II: Room and Pillar-Vertical Drill and Blast System IV: Tunnel Boring-Horizontal Ring Drill and Blast Due to the large number of variables to be considered, a computer program was developed and utilized to provide data for the cost trade-off studies and economic analysis. Results of the early computer runs indicated the value of the tool available? in the computer program and led to an extension in the contract to determine the sensitivity of the systems to several of the more apparent significant variables. These results in turn led to a refinement in the design assumptions and a better understanding of the technical and economic options available to an owner-operator of a Vertical Modified In Situ Shale Oil Extraction System. This report is submitted in fulfillment of the requirements of Contract Number 50241073 by Fenix & Scisson, Inc. to the Denver Mining Research Center, United States Department of the Interior, Bureau of Mines. Work was completed as of November, 1976.

Jan 1, 1976

The goal of the Bureau of Mines diesel engine research program is to reduce exhaust emissions and minimize the risk of fires and explosions caused by the use of diesel- powered equipment in underground mines. This program has led to a fundamental understanding of the problems and to solutions that allow diesel equipment to be used safely and effectively. This volume contains reports of the presentations made at the Bureau Technology Transfer Seminar on Diesels in Underground &fines given in Louisville, KY, and Denver, CO, on April 21 and April 23, 1987. It also contains three reports of related research, not presented at the seminar, which highlight the significant achievements of a joint US.-Canadian research program on diesel emission control technology for underground mines. Topics covered in this volume include discussions of industrial hygiene problems associated with the use of diesels, accident statistics, fire and explosion control systems, measurement of diesel pollutants, emission control techniques including engine maintenance, fuel additives, diesel particulate filters, and ventilation of diesel sections. An alternative to diesel power, the hydrogen-powered mine vehicle, is also described.

Jan 1, 1987

By K. Goshtasbi

In this paper a genetic algorithm is used in a heavily jointed rock mass in order to investigate the critical circular slip surface and modification of slope surface. This method was applied to the southern wall of the 6th Golbini Jajarm bauxite mine. The mine is the largest bauxite deposit in Iran, located to the northeast of the town of Jajarm in the Khorasan province. Estimated reserve of bauxite in this deposit is about 160 million tonnes. Field and laboratory investigations were conducted in order to determine rock mass behaviour. A genetic algorithm code that uses the Simplified Bishop method as an objective function was developed for findingt he safety factor of circular slip surfaces. Sensitivity analysis was applied to determine the optimum values of the genetic algorithm variables, such as population size, selection method, crossover and mutation rates. After finding the critical circular slip surface, slope modification is carried out by removing unstable sections from marked critical slip surfaces, and this process is repeated until the last unsafe section is removed. Based on this code, modification occurred during 7 steps, by reaching a safety factor of 1.3 in the last step. Finally, the modified slope angle of the southern wall of the 6th Golbini Jajarm bauxite mine was determined to be 48.44 degrees. Keywords: Genetic algorithm, slope modification, circular slips surface, 6th Golbini Jajarm bauxite mine .

Jan 1, 2008

By Daniel Connor, O&apos

The Cal-Sag Relief Sewer is a 2.6 m (8 ft 6 in.) diameter 9.1 km (5.7 mile) rock tunnel bored in dolomite for the Metropolitan Sanitary District of Greater Chicago. Included in the project are 18 shafts varying in depth free 70 m (230 ft) to 41 m (135 ft). This paper discusses how Healy/Vanessa reduced costs by eliminating conventional hand excavation by hoisting muck from a high production Robbins TBM (Tunnel Boring Machine) through small diameter drilled shafts and using a trailing rail-utility backup system.

Jan 1, 1985

"Use of the Bond Work Index to size industrial grinding equipment was widely known. Bond also described its application for measuring grinding circuit efficiency. Bond Work Index efficiency has been widely used by industry, but until now without concise standard methods, or a formal guideline, for doing so. The Bond Efficiency Sub-Committee of the Industrial Comminution Efficiency work group of GMSG has produced such a guideline, which follows. It covers the methods and provides examples of how to calculate the Bond Work Index Efficiency of most industrial grinding circuits. Bond Work Index testing equipment and methods are also provided. The next steps are: (1) to establish standard reference testing materials and one or more laboratories to serve as bases for reference testing; (2) to establish the accuracy of relative circuit Work Index Efficiency determinations; and (3), to develop and provide a public data base of industrial comminution circuit Bond Work Index Efficiencies. OUTLINE Introduction and Background Part 1. Determining the Bond Efficiency of a Grinding Circuit Method Demonstration/Example Calculations Bond Work Index Testing Equipment and Procedures Accuracy of Comparative Circuit WI Efficiency Determinations (under development) List of Symbols Part 2. Data Base of Bond Grinding Circuit Efficiencies (under development) References Annexes: A1. The Bond Crushing WI Test Equipment and Procedure for Bond Efficiency Determinations (Revised March 26, 2015) B1. The Bond Rod Mill WI Test Equipment and Procedure (Revised March 26, 2015) C1. The Bond Ball Mill WI Test Equipment and Procedure (Revised March 26, 2015) Introduction and Background Please see the references and slide presentation “Bond Efficiency SLC (rev3)-print.pdf.” This efficiency determination applies to most brittle materials in their naturally occurring (un-scalped) size distributions being treated in size reduction circuits down to a product sizing of approximately eighty percent passing 70 µm (see below). Unusually shaped materials (e.g. mica) should be regarded with caution. Part 1. Determining the Bond Efficiency of a Grinding Circuit Method In the plant: • Define the circuit for which the WI efficiency is to be determined • Procure samples of the circuit feed and product • Obtain the power draw of the size reduction equipment at the drive pinion(s) • Obtain the circuit throughput rate (dry tonnage) In the laboratory:"

Jan 1, 2016

By Gene R. Reid

The contract objective is the development and in mine testing of an Automatic Fire Control System (AFCS) for mobile underground metal mining equipment. The effort described by this report covers the period from June 21,1975 through June 30,1976 and accomplished the following tasks: ? Preparation of Data Handling Plan and data acquisition which included visits to twenty mine sites in eleven states, visits to Bureau and MESA facilities, and a literature survey. ? Data analysis which determined the most hazardous type of vehicle for use in the demonstration, and design requirements for the AFCS, ? Development of recommended design concepts for the AFCS. ? Design and development of the AFCS including tests on a full-scale mock-up of a load-haul-dump (LHD) vehicle. ? Underground fire tests on an ST-2B-LHD vehicle at the Hecla Lakeshore mine Casa Grande, Arizona.

Jan 1, 1976

Jan 1, 1987

By C. Richard Groves

As the level of technology applied in the electrical measurement, control, and display portions of mine hoist systems continues to advance, the issues and concerns associated with the ramifications of the application of microprocessor technology on the safety-related aspects of these systems become paramount. This report, in part tutorial, addresses several aspects of these concerns. Beginning with discussions of microprocessor-based system architectures, the report addresses some existing and anticipated uses of this technology in mine hoist systems and discusses safety related considerations associated with the areas of data derivation; control and display panels; and system reliability issues. The report concludes with electrical maintenance and inspection considerations associated with the safety assurance of microprocessor based mine hoist systems.

Jan 1, 1986

By Henk van der Bijl, Sean Rogers, Eugene Sidorski, Alan Carpenter

The electrode column is the heart of the submerged arc furnace. Superior electrode performance provides improved furnace performance. This paper describes the main features of the electrode column that delivers superior performance in furnaces worldwide, developed by Pyromet. Pyromet?s electrode comprises the compact slipping device, lower electrode assembly, upper and lower mantles, self-adjusting electrode seal, paste heaters, and Pyromet?s patented innovative electrode breakage detection and length determination system. Pyromet?s slipping device features compact interlocking clamping rings, incorporating fail-safe spring-loaded design. The interlocked clamping rings distribute the clamping force over a larger area of the electrode casing, preventing damage. The slipping device assembly features a low maintenance modular design that allows rapid slipping cycle times, back slipping, and compatibility with Pyromet?s electrode breakage detection and length determination system. Pyromet?s lower electrode assembly consists of the contact shoes, pressure bellows, pressure ring and heat shields. The contact shoes and pressure ring are designed for long, trouble free operation whilst the pressure bellow configuration equalise contact pressure and current distribution. Furthermore, the contact shoes incorporate a self cleaning feature, ensuring optimum electrical contact. The segmented design offers easy maintenance. Pyromet?s clients experience less down time due to longer component life. Pyromet?s remote adjusted electrode seal assembly reduces the rope seal working temperature, increasing rope life. The self compensating rope seal clamping force ensures an effective seal as the rope wears. Pyromet?s electrode breakage detection and length determination system detects electrode breaks utilising Pyromet?s electrode holder and data processing system. The length measurement system controls electrode length, eliminating the occurrence of short electrodes. The length measurement system furthermore eliminates the need for manual electrode length measurement, reducing associated production losses during furnace burn downs.

Jan 1, 2007

Identifying Opportunities to Reduce the Consumption of Energy Across Mineral Processing Plants

Sep 13, 2010

By Anton Gronningsater

AS we know, Sir Henry Bessemer introduced Bessemer converting in the steel industry about 1855. It was not until twenty years later that the principles were adopted by non-ferrous metallurgists. In 1880, Manés first produced blister copper from matte in a converter, a very important forward step in copper metallurgy. For thirty years, up to about 1910, bessemerizing of copper matte was carried out in the acid-lined converter. It is not necessary here to enumerate all the shortcomings of that operation, one of which was that it strictly limited the grade of matte that could be treated; a 35 per cent matte was low in those days. From the early days of copper converting, many and repeated attempts were made to use a basic converter lining, and the older metallurgists will remember the numerous reports and discussions in connection with such experiments. These make interesting reading. I quote from a book published in 1900: ?'The siliceous lining is as much a part of the process of copper converting as magnesia lining is in the basic bessemer treatment of phosphoric iron, and it is suicidal to attempt any other kind of lining, either water-jacketed or basic.' "Even if the silica could be introduced in this way (through the tuyeres), it would still produce another trouble in the converter. The small particles of silica, being cold, would combine very imperfectly with the iron oxide and produce granulated and pasty slags, which could not be skimmed or poured out of the vessel".

Jan 1, 1942

By Brian Hart, Stamen Dimov

"The Time of Flight Secondary Ion Mass Spectrometer (ToF-SIMS) is unique in that it measures the outermost atomic layers of any material. The technique is particularly suited for determining surface chemical composition of mineral particles. It is most commonly used as a diagnostic tool to measure mineral surface chemical variability in plant and bench top flotation separation processes. Recently, research towards understanding the full capability of the instrument has resulted in the development of new diagnostic applications related to various Au extraction technologies and the development of the ToF-SIMS as a predictive tool for assessing the chemical reactivity of the ore.In this paper we will present a brief review of the ToF-SIMS technique with recent advances in instrumentation and methodologies including:•,?recent developments and advances towards a semi-quantitative approach to the evaluation of mineral surface modifiers (ex. Cu),•,?flotation case studies investigating activator, depressant and collector loading variability within a flotation process,•,?the recently developed chemical reactivity test which we believe has the potential to predict the behaviour of minerals in a flotation test in response to chemical transfer during grinding,•,recent applications for determination of surface Au preg-robbed in carbonaceous materials.A portion of this material has been recently presented at the COM 2009 meeting and at SIMS XVII (see Dimov et al 2009 and Hart et al, 2009).INTRODUCTIONIn flotation seperation surface chemistry is the principal determinant for selective separation of the various mineral phases (Ralston, 1994, Smart et al, 2003). Determination of this hydrophobic/hydrophilic balance by particle therefore requires correct identification and selection of the particular mineral phase(s) followed by a statistical analysis of the surface chemical characteristics of the particles with an estimation of the spread of values (Smart et al, 2003)."

Jan 1, 2010

By Joseph Grumer

About a century ago Bunsen and his associates invented the famous burner that bears his name and was to become the ancestor of today's gas appliances. Over the years, Bunsen's invention became the starting point of a highly developed, practical technology that culminated in the gas industry as we now know it. However, it did not occur to the early workers to investigate the scientific potentialities of the new device, and as a result the science of gas-burner performance did not keep pace with the growing industry. It was with the objective of closing the rapidly widening gap between science and technology that the present research was undertaken Its immediate purpose was to provide basic information on the combustion characteristics of .fuel gases, in particular as they affect flashback, blowoff, and yellow tipping. Information obtained in the present research and contained within this report consists of the following: (1) Fundamental flashback and blowoff characteristics have been determined, it is believed, for all fuel-gas mixtures in which the gas industry may be interested. These are critical boundary velocity gradients for flames in free air, on burners with ports at room temperature and pressure. Burner aeration is characterized by the parameter, fraction of stoichiometric. These basic limits are explained, values are presented, and calculation procedure is given for deriving corresponding values of port loading and percent primary air (chs. I and II).

Jan 1, 1956

By L. van Hijfte, A. Piché

"Drilling and blasting are fundamental operations in the mining cycle and constitute an important component of the mining costs. Problems associated with improper drilling and blasting practices can create losses of several millions of dollars per year. For this reason, a Blasting Technology program was initiated in 1984 at the Noranda Technology Centre (NTC). In this paper, advances made at NTC in drill and blast technology are reviewed. Impacts of drilling and basting for Noranda are assessed in terms of dilution and ore losses. Future challenges are addressed. IntroductionUp to 1997, Noranda was a diversified natural resources company that operated in three sectors: mining and metallurgy, forest products, and oil and gas. The company employs more than 33 000 people in operations and sales offices around the world. Today, Noranda has returned to its roots in mining and metallurgy. The new vision of Noranda is to be dedicated to the responsible and profitable development of mineral resources around the world for the benefit of its shareholders. In so doing, Noranda will continue to be deeply committed to the environment, health, workplace safety, cost competitiveness and return on capital. Technology is an integral part of Noranda’s success strategies. For this reason, the Noranda Technology Centre, formerly known as Noranda Research Centre, was founded in 1963. Since then, it has undergone four expansion phases to keep up with the increasing needs of the businesses. Today, NTC employs more than 220 specialists who work in partnership with different Noranda companies to identify, develop, and transfer technology to the operations, as well as to explore new sectors of activity."

Jan 1, 2000

By W. William Culver

James Douglas became known in the nineteenth century for two reasons fundamental to his mining career: (1) his experimental work with copper hydrometallurgy, and (2) his grasp of the idea that the quantity of copper ore matters more than the quality. On the first reason, there is a moment for any technology that’s critically important—when it moves from an area of scientific interest to one that companies are founded on. This paper examines the original 1869 Hunt and Douglas Copper Process in the context of science and engineering as they were in the 1860 and 1870s. It was a “humid” process, developed at Quebec’s Harvey Hill Mine. Chemically, the Hunt and Douglas vat leaching process succeeded, but not the original companies using it. On Douglas’ understanding of ore quality versus quantity, luck had it that the first company to field test the Hunt and Douglas Copper Process was in Chile. The Hunt and Douglas patent made that transition from experimental model to operational plant in 1870 when the Compañia de Minas de la Invernada was organized in Valparaíso. As a joint-stock company, Invernada spread the risk of investing in the revolutionary, but untested, Hunt and Douglas Process. The company brought Douglas to Chile as a consultant in 1871. His experience with hydrometallurgy, combined with what he learned about the copper business while in Chile, set him off on a career in metal mining that both surprised Douglas and made him wealthy.

By George S. Rice, F. B. LANEY, A. J. Lanza, Edwin Higgins

Under its organic act the Federal Bureau of Mines is directed to conduct investigations relating to the improvement of health conditions in the mineral industries. This report describes the lead and zino deposits and the mining methods employed in the sheet-ground area of the Joplin district, Missouri, and discusses the causes and the methods of abating rock dust in the mines, the chemical and physical characteristics of the dust, and the quantities present in mine air. Although the preliminary investigation included a number of the "soft-ground" mines, the writer spent the larger part of his time in the sheet-ground mines, for in them alone was siliceous dust found in appreciable quantities. Some results of the preliminary investigation have been published by the Bureau of Mines in Technical Paper 105.a The territory covered in t~lCpreliminary investigation, during the period between November 7 and December 6, 1914, embraced parts of Jasper, Lawrence, Newton, and Greene Counties, Mo., and outlying districts in Kansas and Oklahoma. The remainder of the field work, to which 84 days during the period from February 9 to July 19, 1915, were devoted, was confined to the sheet-ground mines, the most important of which are situated in the vicinity of Joplin, Webb City, Carterville, and other smaller near-by towns in Jasper County, Mo.

Jan 1, 1917

THREE regional meetings are planned for this summer and fall following the spring meeting held under the auspices of the Iron and Steel Committee and the Ohio Section at Cleveland in April and in lieu of a general fall meeting of the Institute. Plans for all of them are maturing rapidly. Excellent programs and. interesting visits to points of local tech¬nical interest are already assured. THE SALT LAKE CITY MEETING This meeting will be under the auspices of the Milling Committee and the Utah Section. It will be one of the features of the joint convention held the week of August 22 to 26 with the Western Division of the American Mining Congress. The Congress will be responsible for the general arrangements and for the program on the first day. The following general committees have been appointed:

Jan 7, 1927

By Henrique Hipolito, Caio Alves

Waelz process is a method applied in the zinc oxide production and is one of the largest sources of carbon emissions within the zinc industry. The solid carbon used for heating and for reduction reactions is provided mainly by the coke fed with the EAFD in the Waelz kiln. Both chemical composition and physical properties of the coke are important to transportation and to the process. Decarbonizing the Waelz process by replacing the traditional fuel source using alternative biogenic fuel, for example, offers a potential solution to reduce the carbon footprint, which is aligned with the ESG perspective.

Sep 29, 2023

By Javier Illanes, Maurice Moore, Felipe Moroni, Rafael Acosta

Any organization that subjects its activities to a continuous improvement process must be able to adequately measure the results of the implemented changes in order to pursue better results over time. This is no different for mining companies. When it comes to blasting, an accurate fragmentation analysis can correlate blast design and rock mass parameters to particle size distribution, enabling us to further analyze the correspondence of specific design patterns, applied to specific rock mass properties and the result in measured fragmentation indicators, such as P80 and fines percentage.

Sep 30, 2022