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By D J. Brake

In most underground mines, the ventilation system is a significant portion of the total mine capital and operating cost and the largest consumer of underground electrical power. The effectiveness of the ventilation system has a major bearing on the safety, health, comfort and morale of underground personnel, and has a critical role in meeting production targets and therefore business revenue. Perhaps the most important component of the primary ventilation system is the primary fan. Correct performance testing of the primary fan during the warranty period is important not only to ensure the mine has obtained the asset that it paid for and can therefore deliver on the fanÆs crucial safety and economic role in the future of the mine, and to provide a justification for releasing final performance warranty payments to the supplier, but also to provide a benchmark or baseline against which to assess future performance issues. As there are at least three potential international standards available to measure fan performance, there has been considerable confusion regarding which of these to use for testing primary mine fans, and also the correct allowances and tolerances to use. This paper provides guidance on which standards to use for different applications, how the standards should be interpreted, what allowances and tolerances are reasonable, and other important issues to be resolved with the fan supplier prior to making a contract award. The paper also discusses practical issues and methodology for in situ primary fan performance testing.CITATION:Brake, D J, 2013. Performance and acceptance testing of main mine ventilation fans, in Proceedings The Australian Mine Ventilation Conference , pp 141-148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By C. W. DeLong, L. L. Farnham, L. A. Stewart

This paper is one of a series covering mineral resources of the Nation . It describes briefly most of the known manganese deposits of eastern Arizona , which for the purpose of this report includes the counties of Navajo , Apache , Gila, Graham, Greenlee , Pinal , Pima , Santa Cruz , and Cochise . With few exceptions , these descriptions are the result of field examinations by the writers . Work on this paper was begun in May 1956 , and in the following 18 months 151 deposits were examined . The distribution of the deposits by counties is as follows : 1 in Navajo , and 1 in Apache , 37 in Gila , 4 in Graham, 13 in Greenlee , 25 in Pinal , 13 in Pima , 12 in Santa Cruz , and 45 in Cochise . In surveyed areas the locations of the deposits are described by section , township , and range and in unsurveyed areas , by approximate projections of these subdivisions . The township and range numbers refer to the Gila and Salt River base and meridian . The history, production, ownership , geologic setting , and mining methods used are discussed for most of the deposits that were visited . Probably , some occurrences have been overlooked , but all of the principal ones have been examined . Ore dressing studies were made of typical ores from several of the larger districts . The work was performed in the laboratory of the Bureau of Mines Tucson Metallurgy Research Laboratory . The results of these studies are given with the descriptions of the deposits from which the samples were taken .

Jan 1, 1961

By D. M. Morrison

"The most important factor in Canadian mining is not the operating cost of current projects but the availability of capital for future projects. The future of mining at depth will be producing ore from the top of the orebody working downward with very effective, tightly controlled mining methods, i.e. either selective mining or bulk mining with well controlled dilution and fragmentation. The key characteristics of future mines will be smaller access excavations, more effective ground support, very precise blasting techniques and more efficient and reliable materials handling systems. Equipment will be smaller and designed for high efficiency and low maintenance, reducing both the capital and operating cost. This means there will be fewer scoops, more continuous mucking machines and conveyor belts, both lateral and vertical.Orepass failures have become accepted and the resultant redevelopment and retramming has become common. The capital investment in so-called permanent ore passes and crusher stations becomes questionable, particularly when crushers are only necessary for less than 10% of the ore going through the system. The best way to solve the chronic instability of ore passes is, as with all of the stability problems at depth, by reducing the excavation size rather than increasing ground support. Smaller access drifts would reduce the capital cost and increase the rate of development as well as reduce the amount of waste to be handled, reducing the ground support and the ventilation requirements. Large drifts and ore passes are essential only for the equipment needed to handle large pieces of ore and the productivity of scoops is very expensive when the requirements for ventilation and large access drifts are taken into account. The key issue is the fragmentation generated by primary blasting.The future of mining in Canada will depend on simple and robust technology geared to the environment in which it will have to operate. Its survival will depend on some-thing much more fundamental and difficult to accomplish than a technological advance — it will require a dramatic change in the way the mining process is managed, how work is organized, how effort is rewarded and how costs are measured — a complete change in mind-set."

Jan 1, 1996

By Sidney Speil

In the study of clays and related minerals, the analytical techniques commonly employed in mineral analysis are not always applicable. The X-ray examination of a clay sample usually will show the major constituents, but often minor· clay impurities will not be detected because of line broadening and the similarity of the main lines of clay· mineral diffraction patterns, The petrographic analysis of clay minerals with clay particles as small as a few microns is usually difficult. With still smaller particles, a gross effect often is noted in which a mixture of several constituents gives the appearance of a single constituent with the mean optical-characteristics of the mixture. 3/ The electron microscope has recently been used to study clay particle shapes of various aluminosilicates. 4/ However, this method has not yet been sufficiently explored. The Chemical method in which a mineralogical analysis is calculated from the oxide chemical analysis has been discussed by Wilson 5/ and others, and many of the shortcomings have been pointed out. It should also be recognized that the variable alkali and alkaline earth content of bentonites makes it inaccurate to assign these basic elements arbitrarily to feldspar or mica in any clay that contains appreciable bentonite.

Jul 1, 1944

By Xiaoqiong Wang, Daobing Wang, Fanbao Meng, Jianbo Wang, Hongkui Ge

"Shale gas has become an important unconventional oil and gas resources. Its effective development relies on comprehensive and accurate understanding of shale gas reservoirs. Rock mechanical properties is one of the important components of reservoir evaluation. Two adjacent black shale samples, which are cored from the depth of 1145 meters in Chongqing, southwest China, are subjected to acoustic emission(AE) test under uniaxial stress and compared with coarse grained granite. The results of synchronous AE, stress-strain and ultrasonic velocity experiments show that shale has weak anisotropy. Compared with granite sample, two shale samples are similar, but their strength, velocity and brittleness are quite different, indicating that shale has strong microscopic heterogeneity. TOC, XRD, SEM microstructure analysis show that total organic content, mineral composition and natural fractures are the main impacting factors for mechanical heterogeneity. INTRODUCTIONShale gas is a typical low-grade marginal resource, which is characterized by ultra-low matrix permeability and small single well control volume. In order to enable commerical development, complex hydraulic-fracture networks must be created in the shale to allow gas to escape from the micro/nano-pores and natural fractures where it is trapped in the rock (C. Clark et al.,2013; Ge et al., 2013). The development of shale gas requires accurate evaluation methodologies to evaluate shale reservoir properties and predict production. (Jarvie et al., 2007). Rock mechanical properties are an important part of the reservoir evaluation. It is significant for efficient drilling, completion and hydraulic fracturing to understand mechanical behavior of shale gas play (John, 2011; Wei, 2013).Rock mechanical properties mainly include heterogeneity, anisotropy, brittleness and acoustic emission activity (Lockner et al., 1992; Jerome et al., 2009; He et al., 2010; Liang et al., 2012). Shale mechanical properties are evaluated from laboratory tests following a complex workflow that covers tasks from sampling to testing (Md. Aminul Islam et al., 2013). It is common to include various experimental methods such as stress-strain curves, ultrasonic velocity and acoustic emission when evaluating the mechanical properties (Rao et al., 2006). Because of the presence of organic-rich matter, mineral composition orientation and natural fractures, shale tends to have strong anisotropy and heterogeneity (Deng et al., 2004; Wang et al., 2013; Hathon et al., 2013)."

Jan 1, 2015

By Charles Tkaczuk

In order to remain competitive the mining industry must keep up with changes in technology. Many innovative technologies from the mining perspective are commonplace in other industries. A ?Global? review of technologies will often reveal existing technologies that can be innovatively applied in the mining industry. Industries, which are rife with proven solutions include, medicine, biotechnology, security, manufacturing, telecommunications, etc. This paper addresses the communications aspect of mining where greater productivity, lower costs and the ability to quickly react to mining related events is obtained through an increase in remote monitoring and operating control. A review of the communications systems in place globally reveals technologies that, with minimal modification, can be immediately applied to the mining environment. We discuss the concept, advantages and implementation of existing communications technology from an industry that is not usually associated with the mining industry. This technology will form the basis of a solid platform on which can be built a state-of-the-art process monitoring, control, and communication system. This lays the groundwork for providing one solution to the underground mining industry?s most difficult problem, establishing a reliable, maintainable and cost-effective underground bi-directional wired/wireless data, video and analog communications system. We need look no further than our own doorsteps to find such a solution. The cable that you see coming from the simple green or brown box on the boulevard into your home contains hundreds of television broadcast channels, FM radio channels and data channels. And if you have a set-top box, you are in control of it all. The Cable Television Broadcast Distribution System suppliers of today are at the leading edge of converging all the different methods of communications onto a common carrier, coaxial cable or fibre optic cable. There is no fundamental difference between providing a reliable communications network to a city/neighbourhood/home/personal computer than there is to a mining operation/underground level/equipment or person. The principle is the same. Only the application is different. Realizing this, we can capitalize on the efforts of other industrial sectors, to solve our communications problem. Where else can you find a solution to a problem that is mature, having been developed with the input of thousands of engineers, and having hundreds of millions of dollars spent on research and development, manufacturing, distribution, global presence and engineering support?

May 1, 2003

By P. deH. Eastcott

The paper summarizes a slide presentation made during the CIM Mechanical-Electrical Operators' Conference, held at Sudbury. Ontario, January 25-27, 1977. Its scope has been limited to a few specific aspects of modern Canadian hoisting plant practice that are likely to be of interest to operating personnel. It is intended to serve as a brief review of established methods discuss in more detail the present state-of-the-art and suggest trends that will appear as products during the next few years.

Jan 1, 1977

After nine years of negotiations, the U.N. Conference on the Law of the Sea approved a Law of the Sea Treaty text in April. Israel, Turkey, the United States and Venezuela voted against the text and 17 other nations including Belgium, the Netherlands, Italy, the Soviet Union, the United Kingdom and West Germany abstained. These nations still have the option of joining the treaty when it is opened for signing in December. However, the Reagan Administration has stated that several provisions of the deep seabed mining portion of the text are unacceptable and it seems unlikely that the United States, at least, will change its position. ALUMINUM Reynolds Metals Co. has criticized an Oregon state plan to relax air pollution standards for aluminum plants. The company feels that relaxation of the rules does not go far enough. Reynolds officials say that they have spent about $31 million at their Troutdale plant for state-of-the-art pollution control equipment, and if they are required to make the pollution reductions called for in the 1986 rules, Reynolds would be forced to close the 40-year-old plant.

Jan 1, 1982

By John P. Capp

After World War II the Bureau of Mines studied methods of producing synthesis gas including a plan to gasify coal in place. Consequently, under a cooperative agreement with the Alabama Power Co., Bureau engineers directed a series of experiments that were carried out on the property of the Alabama Power Co. at Gorgas, Ala. The purpose of underground gasification of coal, regardless of method used, is to obtain the energy contained in the fuel for use on the surface, without mining in the usual sense of the term. Underground gasification can be described as (1) a process where coal, in place, is consumed by partial combustion with air, oxygen, steam, or any combination of these to produce a low calorific value gas (80 to 300 Btu per cu ft) or (2) a complete combustion process in which air is used to produce a gas containing carbon dioxide, nitrogen, and considerable thermal energy.

Jan 1, 1963

By John P. Capp

After World War II the Bureau of Mines studied methods of producing synthesis gas including a plan to gasify coal in place. Consequently, under a cooperative agreement with the Alabama Power Co., Bureau engineers directed a series of experiments that were carried out on the property of the Alabama Power Co. at Gorgas, Ala. The purpose of underground gasification of coal, regardless of method used, is to obtain the energy contained in the fuel for use on the surface, without mining in the usual sense of the term. Underground gasification can be described as (1) a process where coal, in place, is consumed by partial combustion with air, oxygen, steam, or any combination of these to produce a low calorific value gas (80 to 300 Btu per cu ft) or (2) a complete combustion process in which air is used to produce a gas containing carbon dioxide, nitrogen, and considerable thermal energy.

Jan 1, 1963

Many USBM research and information products are available through the systems or formats listed below: Mines FaxBack: Return fax service. 1. Use the touch-tone handset attached to your fax machine's telephone jack. (ISDN [digital] telephones cannot be used with fax machines.) 2. Dial 202/219 3644. 3. Listen to the menu options and punch in the number of your selection, using the touch-tone telephone. 4. After completing your selection, press the start button o your fax machine. Mines Data: Computer bulletin board. Log on via modem through 202/501-0373, or call 202/501-0406 for technical assistance. CD-ROM: This USBM disk is updated quarterly and sold by GPO's Superintendent of Documents. For information on the latest product, please contact Rodger Wedgeworth, 202/501-9557. Internet/World Wide Web: Text and graphics. Access via PC-based browsing software such as Netscape or Mosaic. Universal Resource Locator (URL) is: http:/www.usbm.gov Internet/Gopher Server Text and tables only. Using Gopher client software, access via port 70 as follows: gopher.usbm.gov Internet System Administrator: webmaster@usbm.gov (or contact your local System Administrator).

Jan 1, 1995

Jan 1, 1902

By A. E. Moss

"IntroductionTHE WORLD-WIDE search for iron ore has been vastly accelerated during the past fifteen years .and Canada is playing a most prominent role in this prospecting boom. During this period, the search for .and development of iron ore deposits in Canada bas proven eminently successful and there is every indication that exploration will continue to be active for many years.This paper has been prepared primarily for the information of those who have bad little or no experience in iron ore exploration. For convenience, it is divided into three parts: ( 1) a brief discussion of the marketing of iron ores, with special reference to Canadian production; (2) a summary of the main features to be considered when prospecting for or evaluating a potential iron ore deposit; and (3) an outline of the methods and procedures used in the search for the direct-shipping iron ores in the Quebec•-Labrador iron ore field.The Iron Ore MarketDue to the tremendous tonnages of high-grade direct-shipping iron ore indicated in the iron ore fields of the Quebec-Labrador and Steep •Rock areas, it might be assumed that there would have been a sharp decline in iron ore prospecting in this country. On the contrary, the development of these two major fields, which must be classed among the world's greatest, has been responsible for much of the current activity. The search for high and medium grade magnetite deposits is being• conducted in many parts of the country and a number of these have reached the development stage. Production is being expanded from the known fields, such as Wabana in Newfoundland and Michipicoten in Ontario."

Jan 1, 1955

By B. Benmokrane, G. Ballivy

"RésuméLe mécanisme de transfert des charges et le processus de décohésion le long des scellements d'ancrages scelles dans des massifs rocheux sous des charges de tensionnement peut être examine par instrumentation de l'ancrage à l'aide de jauges de déformation. Dans ce contexte il est présente ici les résultats d'une étude, en vraie grandeur sur chantier, ayant porte, d'une part sur des essais d'arrachement conventionnels et d'autre part sur des essais déflagrée barres d'ancrages instrumentées et scellées à l'aide d'un coulis de ciment dans un massif rocheux sain et compètent. Les résultats décrits ici, particulièrement les profits de contraintes de cisaillement le long de l'ancrage, obtenus à partir des valeurs de déformations relevées sur les jauges, ont permis de préciser le niveau de chargement correspondant à la décohésion initiale du coulis de scellement, d 'examiner l'effet de la décohésion sur la distribution des contraintes et de caractériser le fluage du système barre d'ancrage/coulis de scellement.ABSTRACTThe load transfer mechanism and the debonding process along grouted rock anchor, subjected to tention loads, can be examined through the instrumentation of the anchor with the aid of strain gauges. In this context, the resultsof a full-scale site investigation including classical pull out tests and creep tests are presented in this paper. These tests were performed on instrumented bars which were cement grouted in a competent rock mass. Results presented in this paper concern, among others, shear stress pro/ties along the grouted anchors which were determined from strain values obtained from the strain gauges. These results have been used to: (1) predict the load level corresponding to initial debonding of the grout; (2) study the effect of debonding on shearstress distribution along the anchor; and (3) characterize the creep behavior of the bar anchor/cement grout system."

Jan 1, 1991

By Kung-Lee Wang

This report describes the linkage of all mining sectors with all other manufacturing, services, and final demand sectors of the U.S. economy. Besides being a basic data source, it provides a framework for aggregate economic impact analysis with respect to the mining industries. The framework is an open-static input-output model specifying 48 mining industries as classified in the Standard Industrial Classification Manual for all mining activities and 76 nonmining industries which collectively exhaust, all economic activities. The 124-sector model used in this report is an expansion of the preliminary 82-industry aggregation estimates made by the Department of Commerce. In the expanded model, 48 ruining industries are substituted for the original 6. The methodology used to ascertain the industry-by-industry procurement cost estimates and product ion flows necessary to the construction and expansion of the basic 82-sector model included personal interviews, case studies of specific mining activity analysis, and published and unpublished data from the Bureau of Mines and the Census of Mineral Industries, The end products of this study are two tables arranged to show the direct purchases necessary for each industry to support the level of economic activity and the total purchases generated in each industry throughout the economy by each $1 of aggregate economic demand in 1958. The tables may he used for economic impact studies and market analysis by firms engaged in or closely associated with the mining industries. Some illustrations of their usages are presented.

Jan 1, 1967

By Jay Nopola, Christopher Johnson, Matthew Minnick, Erik Hemstad, Erik Walega

Mining data collection, storage, and interpretation methods have progressively changed over time. Data collection, for the most part, has transitioned from handwritten notes and logs based on manual gauge readings to real-time data streaming through instrumentation capable of directly communicating with site-based data historians or cloud storage. Data collection and storage have had to adjust commensurately with the volume of data, leading to more complex database architecture. Geoscience interpretation methods have also changed; however, the first goals of modeling and understandings from first principles remain the same and are typically deeply rooted in historical academic work. Machine learning methods are becoming more common, available, and implemented by industry and practitioners. Despite the wide accessibility of machine learning methods, the population of geoscience subject matter experts in the underlying theory of this analysis type is limited. This form of analysis, therefore, must be conducted carefully and in conjunction with subject matter experts, on both machine learning theory and the field it is being applied to. This paper aims to provide background history on data analytics and machine learning, current methods and practices, and high-level geoscience case study examples, as well as take aways regarding the mining industry, potential pitfalls specific to geosciences, and possible perspectives on the direction of artificial intelligence in the future.

Jun 25, 2023

By Jeffrey S. Newman

This report presents a summary of the results of a four-phase program conducted for the Bureau of Mines to evaluate underground mine fire detection systems. In addition, Phase IV is presented in detail. The major accomplishments of this program are: 1) quantification and prediction of the distribution of fire products in a mine pas¬sageway; 2) quantification of "equivalent protection" by fire detectors as contained in Title 30 of the Code of Federal Regulations; 3) definition of detection criteria; 4) design of a detector test program for determining detector spacing requirements; 5) design, construction, operation, and calibration of a fire test apparatus for evaluating mine fire detectors; 6) quantification of several mine fire sources; 7) evaluation of several fire detector types including heat, CO and CO2 gas, and ionization smoke detectors; 8) development of generalized spacing criteria for mine fire detectors; and 9) development of performance specifications. Reports for Phases I through III are included in Appendices.

Jan 1, 1984

By H R. Phillips

During the 1980s and early 1990s, the South African coal industry experienced a series of methane explosions in which well over 200 coal miners lost their lives. In addition, a fire and an explosion in the gold mining sector claimed a further 240 lives. These tragic incidents resulted in the establishment of a research facility at Kloppersbos dedicated to explosion and fires research and the funding of an extensive research program, and almost certainly influenced the government of the day in its decision to establish, in 1993, the Leon Commission of Enquiry into Mine Health and Safety. The results of this focused research program, the wide-ranging recommendations of the Leon Commission and the determination of the coal mining industry to improve its safety record all combined to result in the past 20 years without a major explosion.This paper lists some of the research outcomes and, through three case studies, illustrates what can be learnt from investigations following explosions. The paper concludes with an evaluation of some of the findings of the Royal Commission on the Pike River coal tragedy. Many of the Commission’s conclusions are pertinent and relevant to the coal mining industry worldwide and their implementation could significantly improve coalmine safety; however, a careful study of the available facts indicates there could well be an alternative explanation of the source of the methane, the location of the ignition and the size of the explosion at the Pike River coalmine.CITATION:Phillips, H R, 2015. Lessons learnt from mine explosions, in Proceedings The Australian Mine Ventilation Conference, pp 19–28 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By David J. Hatem, K. Bhattarai

The increasing popularity of alternative methods in delivery of underground infrastructure projects has given rise to innovative and collaborative contracting strategies to allocate and manage the unique risks associated with the work. This paper presents approaches and recent examples of how risk has been dealt with using various alternative delivery methods, including Progressive Design Build (PDB) and Construction Manager/General Contractor (CM/GC). Based on the experience gained from these examples, recommendations for an innovative and collaborative risk baselining approach using contingency sharing are presented that should advance the overall goals of equitable risk sharing and compensation.

Jun 13, 2023

1. Domestic Production and Use: In 1980, 13 companies operated 33 primary aluminum reduction plants, with 3 firms accounting for 62% of production. Washington, Oregon, and Montana accounted for 30% of the total production; Texas, Louisiana, and Arkansas 19%; Tennessee, Alabama, and North Carolina 15%; other central and eastern States 36%. Based on published producer prices output of primary metal in 1980 was valued at over $7 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Packaging accounted for an estimated 26% of domestic consumption in 1980, building 22%, transportation 21%, electrical 12%, consumer durables 7%, and other uses 12%.

Jan 1, 1981