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By E. J. Gleim

To make a thorough survey of a coal mine in order to eliminate hazards, the competent safety engineer must be familiar with mere than one branch of engineering. It is essential that he know the properties of mine gases and the methods of detecting them, as well as hew to prevent dangerous as accumulations. It is also essential that he understand the action of overlying strata when the coal is removed, and the proper methods of protection by timbering or other suitable means of support. He must know the value of protective clothing in reducing injuries and mast be informed as to the correct handling and use of explosives to avoid premature blasts, misfires, and ether failures in blasting practice. He must understand hew to operate locomotives and cutting, loading, and various other types of machines to be able to recommend effective safeguards for protecting the men who use them in addition to being informed as 'to these and many ether activities connected with the mining of coal, he must net overlook electrical engineering if he wishes to combat the fire, shook, and ignition hazards attendant upon the use of electrical machinery and circuits in and around the mine intelligently. There are many points relating to safely in the selection, maintenance, and use of electrical circuits and equipment that are perfectly obvious to the electrical engineer but perhaps are not se evident to those not trained in this particular branch of engineering. Engineers of the U.S. Bureau of Mines who have made a special laboratory study of electricity as related to safety in minus haw e also made inspections of electrical installations at a large number of bituminous mines. These inspections have revealed practices and conditions that not only do not contribute to safety but that add nothing to efficiency and economy in the operation of the mine.

Jan 1, 1936

"The business importance of water for mining companies is unequivocal as it may affect several aspects of mining projects ranging from the life-and-death license to operate to the imperative economic viability. It is thus no wonder that nearly all mining companies acknowledge water-related risks, issues and opportunities in their respective sustainability report. Somehow, this procedure has fostered the idea that water frugality could be the sustainable solution to several water-related issues. The regular exercise of water accounting should then follow as a key strategic requirement. Water accounting is defined as the application of a consistent and structured approach to identifying, measuring, recording and reporting information about water. However, several factors discussed herein have led to the fact that some water accounts are still produced using means (hardware and software) which undermatch the value actually associated with water. The resulting fuzziness about water usage could result in missed opportunities, suboptimal operations or even lead to environmental law violations. This paper subscribes to the distinctive perspective that, once underlying concepts and practical definitions have been standardized under a supported framework, such as the openly available Water Accounting Framework (WAF) published by the Minerals Council of Australia, most of the remaining water accounting issues may be boiled down to accuracy issues and, ultimately, to how much accuracy is valued by the stakeholders. Using the latest WAF document as a baseline for best practices of water accounting and, borrowing concepts from the fields of sensor network design in the process industries and best practices of metal accounting, this paper reviews some essential accuracy issues to be considered when designing or analyzing water accounting systems in mineral processing. The current paper also includes some elements for a promising attempt to include the value of information paradigm inside the water accounting best practices."

Jan 1, 2014

By Rita D. Sylvester

THE BUREAU OF MINES was established in the public interest to conduct inquiries and scientific and technologic investigations concerning mining and the preparation, treatment, and utilization of mineral substances; to promote health and safety in the mineral industries; to conserve mineral resources and prevent their waste; to further economic development; to increase efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting these industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the Bureau to "disseminate information concerning these subjects 'in such manner as will best carry out the purposes of this Act.'" In accordance with that directive, the Bureau reports the findings of its research and investigations in its own series of publications and also in articles that appear in scientific, technical, and trade journals; in proceedings of conventions and seminars; in reference books; and in other non-Bureau sources. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make the kind of list and index presented in this special publication both necessary and valuable. This issue describes Bureau reports and articles published during the period January 1, 1960 to December 31, 1964. It, supplements the 50-year list of Bureau publications issued from July 1, 1910, to January 1, 1960,2 and the 50-year list of articles by Bureau authors published outside the Bureau from July 1, 1910, to January 1, 1960.3 It supersedes the annual lists of Bureau publications and articles from January 1 to December 31, 1960,4 from January 1 to December 31, 1961,5 from January 1 to December 31, 1962,6 and from January 1 to December 31, 1963.7 The leading general and technical libraries of the United States maintain files of the Bureau's publications. A list of these libraries appears immediately following this introduction.

Jan 1, 2007

By Robert Torbin

The objectives of the Continuous Shaft Lining (CSL) System are to reduce the costs, safety hazards, and time currently required in lining mine shafts with concrete. The CSL will line machine bored shafts downward from the shaft collar on a continuous basis using an inverted, pressurized slipforming technique. The technique for slip-forming downwards has been demonstrated and refined under this program. The approach taken involved laboratory scale testing of key features of the CSL concept. These feature tests included concrete distribution, concrete sealing, concrete slipforming and development of a reliable concrete mix. Based on these results, a full scale above-ground test facility and CSL were designed and fabricated. The objectives of these tests were to demonstrate the viability of the basic concept; to establish operating limits; and to provide input data and information for the design of a second generation shaft lining system. The results of the program have led to a CSL design and operational philosophy which will need to be tested in an underground environment before industry will accept the technology. However, the next generation CSL promises to meet all the original program technical objectives.

Jan 1, 1983

By S. P. Marsh, D. Banerjee

"Casting processes involve phenomena that occur on widely disparate length-scales. Simulation of macroscopic effects, such as heat transfer and convection, are generally addressed by solving the appropriate equations in discretized form on a finite-element mesh. Microscopic phenomena are described by micromodels that may be empirical or analytical in form. Coupling of phenomena in these two regimes is a critical issue in predicting microstructure and defect formation resulting from macroscopic process conditions. A formalism has been developed for expressing micromodels in a consistent manner using stereological parameters to quantify the geometric characteristics of the developing microstructure. This approach provides a robust and physically consistent method for coupling local micromodels with the macroscopic fields. The macroscopic state variables at each node serve as global constraints on the micromodels that are applied to a local unit volume. An outline of an equiaxed solidification model based on this approach is presented, along with preliminary simulation results. Coupling of convection and enthalpy effects between the micro and macro regimes is also discussed. IntroductionThe primary goal of casting simulations is to improve the reliability of cast parts while minimizing cost and development time. Effective simulations can speed up the mold design process and reduce the likelihood of defective parts by refining a particular casting process on a computer, reducing the dependence on cost- and time-intensive prototype castings. The challenge in developing effective simulations stems from the need to address physical processes that occur over a wide range of length-scales, from microscopic (atomic) and mesoscopic (microstructural) scales to macroscopic distances comparable to the size of the casting itself. Overviews of the various thermophysical phenomena and computational factors that are important in solidification modeling are provided in the literature by Rappaz [1] and Tseng et al. [2].Macroscopically, the solidification process is largely governed by the rate of heat flow from the alloy through the mold wall. Another important effect that occurs on the scale of the casting size is convective flow of the melt, which is driven by density-variations in the melt. Macroscopic calculations employ finite-element or finite-difference methods to solve the sets of equations that govern these effects, and the spatial resolution is determined by the grid spacings used for the calculations. Typical spatial resolutions are on the order of 10-2 to 10-3"" meters. This represents a compromise between the resolution required to simulate the continuum transport processes accurately, and the computational time required to model the entire solidification and cooling process."

Jan 1, 1994

By C. Ramasamy

The tariff reductions on imports, as a part of on-going liberalisation process in India, has fueled competition within and outside India and has, in turn provided an opportunity to reach global markets. This change calls for quality upgrades and cost-competitiveness without impairing the environment. In this context, gas based processes, contributing to improvement in quality and environment as well as processes where controls are applied when gases inimical to environment are involved, are discussed in a remelt/cast-house scenario. The impact of such processes on fabrication cost of sheet ingot is seen alongwith consumption and cost of materials and compared with a world class standard plant in North America.

Jan 1, 1996

By M. Ploc

The grinding process in the mining industry has seen an increased throughput to accomplish greater production and lower overall production costs. Up to 8-9 MW, a single motor can be connected to drive the mill through a pinion and ring gear. Above the single-pinion drive limit, the dual pinion approach was developed to allow two drive motors to be used. This allowed the mill input power to be increased to 16-18 MW. Recent developments in clutch and ring gear materials and design are allowing greater input powers of up to 20 MW to be considered. To avoid damage to the ring gear by uneven load sharing between the two motors, it is critical that the two machines accurately share load. This is typically achieved by either drives capable of controlling load torque between motors or using a GE proprietary control system that accurately controls the load torque from each motor.

Jan 1, 2010

By M. L. Leming

The mechanisms of Alkali-Silica Reactivity (ASR) are briefly reviewed, test methods are examined, and typical specifications are discussed. In addition, views on responsibility of the aggregate supplier regarding specifications are presented.

Jan 1, 1995

By C. W. Davis

During the fiscal year 1935-36, the Ore-Testing Section has been active in carrying out a program designed to attain the objectives that have been set up for it. For the Purpose of standardizing important testing methods, an attempt has been made to develop a rationalized scheme for ore testing, starting with preliminary investigations to determine the physical and chemical properties of the ore, following this with a logical selection and trial of processing tests to find out how the ore may be most effectively treated, and concluding with a discussion of what interpretation may be placed on the results in terms of plant design and operation. A selection of Procedures that appear well-suited to the ore-dressing problems under investigation is included in the following paper of this report so that other experimenters may be enabled to verify our findings and to offer criticisms and suggestions for improving our practice. A tentative scheme for the evaluation of flotation reagents is being investigated, and some progress has been made in a study to determine the significance of small-scale testing. These projects have required 899 analyses. Papers on these and others on ore testing, such as testing for amalgamation and for cyanidation, will be included in future annual reports.

Jan 1, 1937

By R. Hazael, R. Alford, R. Critchley

The ability to compare explosives is fundamental. Numerous methods are used and while simple conversion factors are often used, the use of TNT Equivalency (TNTe) is not a simple subject as explosives exhibit very different equivalencies depending on whether the pressure or impulse are being considered as well as other conditions. The scaled distance has been found to have a significant effect on the TNTe but due to the difficulty of taking measurements at very close ranges, no TNTe have been quoted for charges in direct contact (Z=0). This paper describes the use of a ballistic pendulum to measure the impulse from contact charges and presents some surprising results that require a two-stage propulsion, as originally described by Backofen, to be explained.

Jan 1, 2024

By R van Wyk

In today’s mining environment the use of heavy mechanical devices and other high-tech electronic devices like two-way radios, cellular phones and even automated mining systems, form a vital part of the daily operations of a mining site. These human-made devices and some of the naturally occurring events, like lightning and gamma radiation, can have negative effects on electronic detonators and the associated control equipment.On larger mining operations the necessity to move the point of safety for blasting further away from the blast area, introduced remote firing via radio frequencies for electronic detonator systems. Other influences on electronic detonators can be abuse or ignorance. To ensure the safety of the end-user, an electronic detonator must be resistant to some common mistakes that users can make. One of main concerns here is resistance to static discharge or incorrect wiring. Despite the daily use of electronic detonator solutions, scepticism and concern still exists amongst those who believe the system raises the risk of a premature initiation of the blast through some form of interference trigger.This paper will help users understand how electronic detonators and the associated control equipment protects itself from external influences. Focus will be on protection schemes to counter static and over-voltage discharge and methods to ensure protection of secure wireless radio links and detonator communications. With well engineered communication systems and solid static and over-voltage protection, an electronic detonator system can be more reliable and safer than other detonator systems. The following main points will be discussed:what makes a detonator an electronic detonator,static electricity and over-voltage protection,the general influence of electromagnetic energy on the detonator,the influence of lightning on detonators,the protection of radio communication’s links as used by remote firing equipment, andthe safety protection features built into remote firing equipment.

Nov 8, 2011

By Karl Berger, Michael Steinkogler

The evolution in Metal Cutting: Inventors around the world have been successfully developing innovations for decades, but only some of these developments have had „GAME CHANGING“ potential. One of these innovations is the new developed saw blade LINCUT®, a patented changing system that paves the way for a fundamental reorientation of the entire saw blade industry worldwide through a simple and economical concept for rolling mills or heavy forging lines. Cost efficiency starts with the raw material: Circular saws equipped with a standard saw blade are expected to have a necessary 2 percent standstill per year due to required tool changing. The applied technology reduces this unnecessary loss of production by more than 50%. The ROI can therefore be reached faster which immediately lowers your production costs. No matter what material, conventional carbon steel or highly alloyed stainless steel, the coating and shape of carbide plates is perfected for extended tool life up to 25% with increased performance. Due to LINSINGERs own tool-technology-centre in Austria specialized in research and development of tools, constantly expanding R&D activities, best results are achieved in quality and cost efficiency: a (r)evolution in metal cutting.

Oct 1, 2019

By Unknown

We are indebted to the Consolidated Mining and Smelting Company of Canada Limited for the several pictures in this issue showing the progress made in new construction at Tadanac and at Bonnington Falls, B.C. Plate No. 1 shows the down-stream side of the No. 1 hydro-electric station of the West Kootenay Power and Light Co. Limited at Bonnington Falls, on the Kootenay river, at which 17,500 k.v.a. will be developed to meet the requirements of the enlarged zinc and lead refineries at Tadanac. The generators, exciters and switch apparatus were supplied by the Canadian General Electric Company and the step-up transformers by the Canadian Westinghouse Company Limited. The plant throughout was designed, manufactured and erected by Canadians. Plate No. 2 shows the casting room of the new lead-plant and plate No. 3 the new tank-room of the electrolytic lead refinery at Tadanac. These additions will increase the capacity of the lead refinery by some 150 tons daily. The extensions also include practically doubling the zinc plant, and the gold and silver refineries. With the exception of the new stack, all designing construction and installation of the various plants is being done by the Company's own employees at Tadanac. Plate No. 4 shows the progress made in the construction of the new reinforced concrete stack at Tadanac. This stack, of 21 feet inside diameter at the top, will be brick lined and when completed will rise 400 feet above its foundations: the tallest of its kind in the world. The construction is in charge of the Rust Engineering Company of Pittsburgh, Pa. Plate No. 5 is a panorama of the Tadanac smelters and refineries. The photograph was taken from the roof of the lead smelter and gives an excellent idea of the size of the plant and its surroundings. Tadanac produces electrolytic lead, zinc and copper and fine gold and silver. During 1924 the company treated 1,333,523 tons of ore and produced: 161,400,- 769 pounds of lead; 92,197,824 pounds of zinc; l,382,750pounds of copper; 4,074,044 ounces of silver, and 26,976 ounces of gold.

Jan 1, 1925

By BUREAU OF MINES

This report is submitted in accordance with the provisions of the Synthetic Liquid Fuels Act of April 5, 1944 (30 U.S.C. 321-325, as amended), which require that: "The Secretary of the Interior shall render to Congress on or before the first day of January of each year a report on all operations under this Act." Owing to the broad scope of the content and the diversity of interests represented, the Annual Report for 1953 has been divided into two separate publications. Each has been published by the Bureau of Mines as a Report of Investigations, and the respective titles follow: R. I. 5043, Part I - Oil From Coal. R. I. 5044, Part II - Oil From Oil Shale. Identical in each report, the introduction summarizes research progress made in 1953 under the entire Synthetic Liquid Fuels program. A free copy of each of these publications may be obtained by a written request to the Bureau of Mines, Publications Distribution Section, 4800 Forbes Street, Pittsburgh 13, Pa. The R. I. number and title of the publication desired should be indicated.

Apr 1, 1954

By Raymond L. Lowrie

Coal deposits in the Boulder-Weld County coalfield in Colorado are analyzed in relation to economic factors governing the growth, stability, and competitive potential of the coal industry. Recoverable reserves, estimated to be 571 million tons, are discussed in detail, particularly those in the Erie and Frederick Quadrangles. Geology of the coal measures, quantity and quality of water resources, and chemical and physical properties of the coal are described. Coal production factors, including mining techniques and equipment, labor requirements, transportation facilities and rates, and markets, are considered for coal's position in competition with alternate fuels. Growth of the fuels market, through increasing thermal-electric power generation in the Denver Metropolitan Area, will stimulate coal production in Colorado. Reserves of the contiguous Boulder-Weld coalfield, if mined in a sustained, year-round, high-tonnage operation, could be used to supply much of that fuel demand.

Jan 1, 1966

By R. Addison, T. Swendseid, R. Kehmeier, D. Larsen, J. Uhrie

"The development of a mining project necessarily progresses through many steps, beginning with the identification of a mineral resource and continuing through project construction. Several classifications of engineering study development are described, including preliminary economic assessment (PEA) or scoping studies, prefeasibility studies (PFS), feasibility studies (FS) and regulatory codes, each with a specific project organizational objective. This paper addresses the PEA, PFS and FS types of reports that are used by companies to evaluate projects, meet regulatory requirements and seek financing. The minimum requirements for engineering studies, focusing on the needs of financial institutions considering investment in a project, are outlined. IntroductionThe financing of mining projects in recent years has come under increased scrutiny by financial institutions owing primarily to an increasing percentage of projects whose capital expenditures had overrun project budgets or had failed to produce the economic returns anticipated during the project development process. Often, unfavorable project outcomes are not the result of widespread failures of the project engineering process but arise from inadequate engineering in limited specific areas of the project scope, such as overestimated mineral reserve, inadequate mine design, insufficient metallurgical testing or underestimated capital costs. Mill facilities and process infrastructure typically are responsible for up to 80 percent of the capital expenditures required by greenfield mining projects. They are often the project areas where capital costs are inadequately developed, and consequently are the areas highly scrutinized by financial institutions. This paper offers a perspective on the level of engineering expected by financial institutions as a prerequisite to committing support to developing mining projects.The evaluation of a mining project from exploration through development and production is a lengthy and complicated process. Mine development commitment activities for a potential project are initiated when a mineral resource is identified and continue through to the start of construction. The technical feasibility and the economic viability of each project are determined during the phases of mine development with more detailed engineering data required at each stage. There are at least four levels of engineering studies during development that are commonly acknowledged by the mining industry:"

Jan 1, 2016

By G. J. McTeer, D. L. Verhelst, D. J. Rioux

Teck Metals Ltd. operates an integrated zinc-lead complex at Trail, British Columbia, Canada. Since 1997, KIVCETTM flash smelting technology has been utilized for the treatment of zinc plant residues and lead concentrates. Trail Operations’ furnace uses four water-cooled jackets for bullion tapping. This paper provides an overview of KIVCET bullion tapping for the past 16 years, and discusses successes and challenges encountered with respect to operations, training and monitoring.

Jan 1, 2015

By Nicholas Bonderoff, Amily Xu

The evaluation of battery electric vehicles (BEVs) in underground mines involves comprehensive business case analysis beyond just the capital and operating costs of the equipment itself. BEVs demonstrate benefits from an EHS perspective, reduced mine ventilation costs, lower energy operating costs, reduced overall GHG emissions (dependent on the source of electricity), elimination of DPM, lower equipment maintenance costs, and reduced cooling requirements in deep mines. When including batteries and supporting infrastructure, BEV capital costs are approx. 80% greater than that of diesel equipment. The project economics are highly dependent on the cost of electricity and diesel fuel, and these can vary widely depending on the location of the mining operation. Battery charging and swapping methodologies must be evaluated as there are a variety of approaches that can be employed which vary by manufacturer and type of equipment. Careful consideration of the cycle times, charging methodologies, and location of the battery charging infrastructure is necessary. Specific operating conditions must also be taken into consideration. For example, the time for blast gases to clear will be increased by reducing ventilation flow, and the potential impact on production needs to be evaluated. Similarly, the electrical distribution system needs to be evaluated for peak loading conditions when BEVs are charging. Criteria including maintainability, reliability, commercial availability, and performance need to be evaluated. BEVs have fewer components than diesel equipment and this correlates to lower overall maintenance costs, however, BEVs require maintenance personnel with specific skill sets in order to maintain the equipment. Battery lifecycle costs need to be considered as battery replacement incurs significant capital expense. Some manufacturers offer services to offset these capital costs through usage agreements. Recycling and disposal of batteries at the end of their lifecycles also need to be considered. With the increased selection of BEV equipment that will be available in the next 2-4 years, 100% BEV adoption is also possible. We recommend a holistic approach when evaluating BEVs for underground mines. This will ensure that everything is considered in order to evaluate the full impact of BEV implementation.

Jan 1, 2023

By Ataç Başçetin, Hasan Çelt, Hüseyin Onur Dönmez, Kürşat Hasözdemir

Phenolic foams, known for fire resistance, show broader industrial potential, particularly in mining, through property enhancements. Adjustments to the formaldehyde-to-phenol (F/P) ratio, bio-based additives like lignin, and nano-silica improve foam strength and thermal stability. Density modifications allow foams to range from flexible, low-density forms to rigid, high-density supports. In mining, enhanced phenolic foams could reduce coal ignition risks by acting as oxygen-blocking barriers. Current findings suggest these foams offer viable, sustainable solutions for safety in hazardous environments. Continued development could make them essential for thermal and mechanical applications under extreme conditions. This paper aims to provide a comprehensive overview of the mechanical characteristics of phenolic foams, current enhancement strategies, and standardized testing methods used to evaluate foam properties.

Feb 1, 2025

By C. W. Davis

During the fiscal year 1935-36, the Ore-Testing Section has been active in carrying out a program designed to attain the objectives that have been set up for it. For the purpose of standardizing important testing methods, an attempt has been made to develop a rationalized scheme for ore testing, starting with preliminary investigations to determine the physical and chemical properties of the ore, following this with a logical selection and trial of processing tests to find out how the ore may be most effectively treated, and concluding with a discussion of what interpretation may be placed on the results in terms of plant design and operation. A selection of procedures that appear well-suited to the ore-dressing problems under investigation is included in the following paper of this report so that other experimenters may be enabled to verify our findings and to offer criticisms and suggestions for improving our practice. A tentative scheme for the evaluation of flotation reagents is being investigated, and some progress has been made in a study to determine the significance of small-scale testing. These projects have required 899 analyses. Papers on these and others on ore testing, such as testing for amalgamation and for cyanidation, will be included in future annual reports.

Jan 1, 1937