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By Z. Zhang, R. G. Reddy

Viscosities of industrial lead slags with various compositions were measured as a function of temperature using a Brookfield viscometer. Based on the experimental data from this study and other investigations reported in the literature, an expression has been developed to correlate the viscosities of lead silicate slags as functions of composition and temperature. The effect of each individual slag component on the variation of the slag viscosity is identified. The composition dependency of viscosity of lead silicate slags is discussed. The calculated results using this viscosity expression are in good agreement with the measured data.

Jan 1, 2001

By D. L. Watson

In spite of the deflationary state of the minerals business today, there will be opportunities for those who can fulfill future needs. Since there are abundant supplies of ores and fuels to keep prices down, at least in peacetime scenarios, future needs may be as much political and social as technical and economic. Engineers and economists will develop new and innovative ways to find, mine, process and pay for mineral deposits. Pressure from governments and non-governmental organizations and the public will combine with market forces to provide opportunities for highly competitive, risk-taking enterprises who can leverage the qualities of their orebodies and employees by being good neighbors and partners.

Jan 1, 2000

By A. W. Czarnowsky

More than ever before, mining projects are besieged from growing regulatory, political, public, and special interest group pressure. Administrative and legal appeals to permits and environmental documents can delay project start-up and add tremendous cost to mineral development. Some mining projects have been canceled given undue external constraints. Successful managers must learn to cope with these constraints. This paper will discuss controversy and present a number of environmental management tips to minimize the potentials for delay and to lessen the impacts from government and anti-mining pressures.

Jan 1, 2001

By A. M. Anthony, A. Y. Atta, S. S. Magaji, U. Abubakar-Zaria

There are two major gold recovery methods: the hydrometallurgical technique, which employs cyanide solutions, and amalgamation method, which involves mercury (Hg). These methods present considerable health, safety, and environmental concerns. Past applications of alpha-cyclodextrin (α-CD) on gold scraps show that α-CD is not only inexpensive, but is also environmentally friendly. This research work used α-CD to recover gold from gold ores instead of gold scraps. The gold ore was sourced from Shanono gold deposit site Kano State,Nigeria. The gold ore was characterized by fire assay (FA) for the precious metal. The concentrate was digested with aqua regia (AR) for 24 h. Modified AR, where hydrochloric acid was replaced with hydrobromic acid, was used for the gold digestion due to the good match in molecular recognition between gold bromide ion (AuBr)− and α- CD in a second sphere coordination complex. The digestate was characterized using atomic absorption spectroscopy (AAS). Gold recovery using this technique is pH sensitive, and five pH values (2.0, 3.6, 4.0, 5.4, and 6.0) were investigated. FA analysis showed the Shanono gold ore deposit contains an average of 4.71 ppm of gold, AAS analysis showed highest gold recovery of 69% at pH 4.0, which is lower than recoveries from the metal scraps. This could be due to the presence of other gangue minerals closely associated with the ore. However, gold recovery using α-CD on Shanono gold ore has shown to have a higher yield of 69% compared to 35.5% yield obtainable by Artisan Small Scale Miners using mercury.

May 5, 2020

By Bahram Sameit

Blast engineers have been taking advantage of image-based rock fragmentation analysis methods for the past three decades to estimate rock size distributions. These methods utilize a range of image segmentation techniques, from manual to fully-automated, to delineate the edges of rocks in images. Rock delineation results are then converted to physical rock sizes (and percentage passing curves) by scaling the image pixels to correspond to physical measurements. The size scaling process is critical for acquiring physical measurements, but specifc to the limitations of different applications. This article starts by presenting a shovel bucket-based fragmentation analysis system, where scaling is done using the known width of the shovel bucket within the image. It will then describe methods that use pictures captured by digital cameras with scaling reference objects in the view. Finally, the article presents a method that uses three-dimensional imaging to capture images without the need for scaling reference objects.

By W. G. Pariseau

Joints may be taken into account when using numerical modeling as an aid to mine design by embedding joints in the model. When using the popular finite element method, say UT3PC, a pre-analysis step is necessary, Step 0. This step is for the computation of equivalent properties of a representative elementary volume of jointed rock (REV) in the model. This Step 0 is taken before Steps 1, 2 and 3 for specification of a rock properties file, generation of the mesh, and model analysis are taken. A brief explanation of equivalent properties and several examples aid in explaining the details of Step 0. Focus is on procedures, input files, and output to show ease of computation. Theoretical details are relegated to references (e.g. Pariseau 2022). Comparisons of safety factor distributions about example mine excavations with direct scaling from mine observations then offer some insights concerning equivalent properties, especially strengths.

Feb 1, 2023

By J. S. Gardner, J. J. Zaluski

I. INTRODUCTION West Virginia has a long history of coal production.1 The state at one time led the nation in total coal production, while at the same time coal from West Virginia constituted one quarter of total U.S. coal production.2 In more recent years, however, West Virginia’s level of coal production has been reduced in comparison to that of other states due to the high relative cost of producing coal in the state.3 Another blow to the producers of coal in West Virginia is the action known as Bragg v. Robertson.4 In 1998 various individual plaintiffs, as well as a conservation group known as the West Virginia Highlands Conservancy, filed a civil action under a provision of the Surface Mining Control and Reclamation Act of 1977, Pub. L. No. 95-87, §522, 91 Stat. 445 (codified at 30 U.S.C. §§1201-1328) ("SMCRA" or the "Act") that allows declaratory and injunctive relief against state and federal officials for non-compliance with the Act.5 The plaintiffs generally claimed that the Director of the West Virginia Department of Environmental Protection ("WVDEP") had exhibited a pattern of violating mandatory non-discretionary duties under SMCRA and the West Virginia state regulatory program.6 These non-discretionary duties involved many areas of regulation, including water quality standards, disturbance of wetlands, hydrologic reclamation plans, Approximate Original Contour ("AOC") requirements and AOC variances, post-mining land uses, contemporaneous reclamation, and as explained later, the "buffer zone rule."7 In addition to these claims against WVDEP, the plaintiffs also alleged that certain individual members of the Army Corps of Engineers (the "Corps") had failed to carry out statutory duties under the Clean Water Act (the "CWA") and the National Environmental Policy Act ("NEPA").8 Generally, the complaint stated that the Corps did not have statutory authority under the CWA to regulate valley fills created for the purpose of the disposal of waste material, i.e., the overburden associated with mountain top mining.9 Alternatively, the plaintiffs claimed that even if the Corps could regulate valley fills, the Corps violated NEPA by issuing nationwide permits without required analysis. Finally, the plaintiffs asserted that the issuance of a nationwide permit for surface mining valley fills is unlawful.10

Jan 1, 2001

By X. Zhu, R. Du Plessis, J. D. Miller, D. G. Kotylar

Research on the low-potential hydrophobic state of pyrite with potassium amyl xanthate (PAX) as collector, is reported to help explain and understand the fundamental aspects of the N2TEC flotation process, which was originally developed for the improved recovery of gold from refractory auriferous sulfide ores. Typically in the N2TEC process, air is replaced by nitrogen as the flotation gas, and potassium amyl xanthate is used as collector for the reactive auriferous pyrite particles. The first N2TEC flotation process was commissioned at Lone Tree in Nevada in March 1997 and has been in operation ever since. On the basis of electrochemically controlled contact angle measurements, the low-potential, low-pH hydrophobic state of pyrite has been examined as a function of flotation variables such as pH, gas-phase composition, collector concentration and pyrite potential.

Jan 1, 2000

In practice, frothers are selected following general guidenlies and verification by laboratory and/or plant flotation tests. The terms “powerful” or “selective,” which are commonly used to characetrize frothers, have intuitive rather than scientific meaning. A research program has been set out to study fundamental properties of the flotation frothers and to identify the tests which can provide information needed to characterize and classify such flotation agents.

Jan 1, 2004

By J. F. Burr, D. P. Snyder, G. W. Luxbacher

"The Mine Improvement and New Emergency Response Act (MINER Act) of 2006 established the Office of Mine Safety and Health (OMSH) within NIOSH and provided authority for awarding contracts related to the development and implementation of new mine technology and equipment. Subsequently, Congress provided additional funding to NIOSH to initiate and continue the program. OMSHR has fulfilled this Congressional mandate through annual Broad Agency Announcement (BAA) solicitations, directed Requests for Proposals (RFP) and Inter-Agency Agreements (IAA), and has further expanded the program through capacity building BAA contracts with U.S. university mining departments in the areas of mine ventilation and ground control. This paper describes the extramural funding program and broadly examines the results of the 150+ contracts issued to date, grouped into key focus areas. INTRODUCTION The Mine Improvement and New Emergency Response Act (MINER Act) of 20061 established the Office of Mine Safety and Health Research (functioning as the Office of Mine Safety and Health Research or OMSHR) within the National Institute for Occupational Safety and Health (NIOSH), and provided authority for awarding contracts related to the development and implementation of new mine technology and equipment. The OMSHR external contracts program was formed in accordance with the MINER Act and has since issued over 150 contracts focused on worker health and safety. Initial funding for this program was provided by Congress through two Emergency Supplemental Appropriations (ESA) and was focused on emergency oxygen supply, communications and tracking, and refuge chambers (also referred to as refuge alternatives). Since the MINER Act, Congress has continued to fund the program through the annual NIOSH mining appropriation. The program was supplemented starting in 2009 with an academic capacity building program directed toward developing university tenure-track faculty and facilities and supporting graduate students in the area of mine ventilation; ground control was added as an additional focus area in 2011. A short synopsis of each contract is published on the NIOSH Mining website2 and final reports are available in digital form on request. A summary of the progress OMSHR has made over the 10-year period since the Act was published previously.3"

Jan 1, 2018

By R. B. Elver

The St Lawrence Seaway, a deep-water canal system between Montreal and Lake Ontario, was opened for navigation on April 25, 1959. Prior to the opening of the new Seaway, small boats known as canalers and a few deep-sea carriers, primarily from Norway since World War II, were the only ships able to journey past Montreal into Lake Ontario through the old Canadian St. Lawrence canal system. Thus it was necessary for many tons of bulk and general cargo to be shipped all-rail to and from Atlantic ports or to be transhipped to and from canalers. With the opening of the new Seaway, large Great Lakes bulk carriers and a much larger percentage of the world's shipping fleet are now able to sail directly from the sea to the heart of industrial North America. In this paper, the historical events leading up to the construction of the Seaway and the physical nature of the Great Lakes transportation system are briefly reviewed. Following this, an attempt is made to evaluate the effects of the new Seaway on Canada's mineral industry. Because the Seaway has been in operation for only one season, this paper must be considered only an interim report. Because of the importance of the Seaway to iron ore, this commodity will be dealt with in detail, although the effect on other mineral commodities such as coal, petroleum, nonferrous ores, iron and steel will be mentioned. At this time the author wishes to thank the various company and government officials who provided both factual information and critical opinions.

Jan 1, 1960

By K. H. Boss

In modern iron pelletizing plants fuel consumption has been optimized to such an extent that only minor savings can be expected in the future. Inspite of this fact, different process parameters were studied with a mathematical model and firing tests. The influence on fuel consumption and productivity was established. Furthermore, the adoption of simplified firing patterns was investigated, in particular for coal firing. In view of high costs of oil and natural gas, only substitution of these fuels by coal can substantially reduce production costs. In existing plants partial replacement of oil and gas can be achieved by addition of coal to the iron ore feed and by firing the pellets with pulverized coal. Two systems have been developed for the Lurgi- Dravo travelling grate process which enables coal to completely replace oil or gas. This paper describes in the first part the potentials for fuel savings available in the Lurgi-Dravo process. In the second part, different techniques for the use of coal as fuel in iron or pelletizing plants and in particular the recently developed Lurgi Multistage Coal Injection and Combustion Process (LMC) are discussed. Combined with the LMC process, a wide variety of iron ores and coals - also with high ash contents - can be used in the Lurgi-Dravo travelling grate process.

Jan 1, 1983

By L. Lacerda, C. Rose, E. Zellers

Approximately six hundred air sample measurements were taken at several U.S. underground metal/nonmetal mines in 1998 and 1999. This air sampling effort was organized by the Nevada Mining Association to evaluate mining conditions and to evaluate the Mine Safety and Health Administration’s (MSHA) Proposed Rule on Diesel Particulate Matter Exposure of Underground Metal and Non-metal Miners. MSHA’s proposed air sampling method, NIOSH Method 5040, was tested under controlled conditions and under normal mining conditions. Unfortunately, NvMA sampling results have indicated that carbonaceous rock dust, oil mists and even cigarette smoking create severe sampling interference problems for NIOSH 5040.The main conclusion was that NIOSH 5040 did not distinguish between DPM and other airborne carbon particulate. Thus, it is not a reliable method of accurately and unequivocally measuring DPM in underground metal/nonmetal mines.

Jan 1, 2000

Commercialisation of outcomes from research projects is a process often poorly understood and managed, but has the potential to achieve significant benefits for the industry and community as a whole. JKTech Pty Ltd was established in 1986 to transfer viable research outcomes from the Julius Kruttschnitt Mineral Research Centre (JKMRC) at The University of Queensland, Australia. This paper describes successful and unsuccessful examples of commercialisation by JKTech over the years, and draws some conclusions as to the factors that contribute to success and failure in technology transfer.

Jan 1, 2012

By D. M. Jepsen

One of the first things we tell a potential new client is that they have only one chance to make a first impression with an Aboriginal community; all future communications and engagement will be predicated on that first impression. The key components of this most critical meeting are not your power point, your maps, or your draft plan for development ? they are instead a genuine, evident and clear demonstration of a sincere desire to develop a positive relationship that is based upon respect, and consideration and understanding of local communities and their interests, needs and desires. Relationship building is the foundation of proactive and positive consultation and accommodation with Aboriginal communities and the tone is set with the first meeting. C3 has refused more clients than we have accepted due most often to the fact that relationships between the company and the Aboriginal community have already devolved into a tense and toxic scenario. Land access and tenure certainty for exploration and mine development is critical to the foundation of a healthy, sustainable and environmentally and economically sound mineral exploration and mining sector. Without certainty confidence to invest in mineral exploration will be severely eroded. We all understand that substantive investments in exploration are required to increase the possibility of discovering, defining and developing new mines. The development of positive relationships based on a shared commitment of understanding, mutual respect and trust by Aboriginal Peoples and the mineral sector can provide the required business certainty and deliver social and economic benefits for local Aboriginal communities.

Jan 1, 2012

THE QUARTETTE Mine near Searchlight, NV, a mine that first operated in the 1890s, could begin processing ore again by September. Jetco Enterprises Inc. plans to work through the tailings and ore close to the surface followed by plans for an openpit mine. It is one of at least three new mining efforts in the region, the Associated Press reported. Another is north of Searchlight, with yet another across the Colorado River in Arizona, east of Bullhead City. Gold mining is rare in southern Nevada. The area generally lacks the rock type that contains gold deposits. Restrictions on federal wilderness areas and protections for the desert tortoise also play a role. Gold veins in the region are generally small and erratic in length and height, Bill Durbin, a geologist and chief of southern Nevada operations for the Nevada Division of Minerals told the Associated Press. L.R. Tad Tinnell, president of Jetco Enterprises, has long eyed the mine. From 1993 to 1995, he explored and drilled on the property, which was still owned by Searchlight Mercantile.

Sep 1, 2013

Ceremonies for the induction of five mining industry pioneers into the National Mining Hall of Fame are scheduled for Saturday, Sept. 25, 2004 at the Las Vegas Hilton in Las Vegas, NV. The 17th Annual Mining Hall of Fame Induction banquet will begin with a reception at 6 p.m., followed by the dinner and program at 7 p.m. The five inductees are Georgius Agricola, David William Brunton, Herbert E. Goodman, David Ray Mitchell and Robert Peele. Georgius Agricola (1494-1555) wrote De ReMetallica, an original and valuable work that discussed everything known about mining during the first half of the 16th century. In De Re Metallica, Agricola reviewed practical means of finding ores, methods of surveying and mining, the assaying of ores, types and uses of mining machinery, smelting, mine administration and more. David William Brunton (1849-1927) is best know

Jan 1, 2004

By T. F. Tomb

Although the number of operating longwalls (approximately 100) has remained relatively constant over the last five years, longwall production levels have significantly increased and have in some cases more than doubled. As a result of the increase in production, control of respirable dust continues to be a problem. Therefore, the Mine Safety and Health Administration (MSHA), Pittsburgh Health Technology Center, Dust Division, initiated a study to investigate the availability and adequacy of technology for controlling dust on longwall mining operations. The study involved 23 longwall mining operations in three different Coal Mine Safety and Health Districts. Each operation was visited for a full shift. Respirable dust samples were collected on face personnel and at fixed locations along the face. Parameters in place to control dust were noted with special emphasis being placed on obtaining quantitative data relative to ventilation, headgate dust controls, cutting drum sprays, external machine sprays and cutting sequence. Attempts were made to correlate dust control parameters in place at the time of the visit to dust concentrations measured at the tail, on the tail shearer operator and to the average concentration of dust determined from averaging all the measurements from the occupations sampled. The parameters in place to control dust were also compared to the gamut of technology known to be available to control dust. This paper presents a discussion on the effectiveness of the parameters in place to control dust and on the availability of technology for the control of dust on longwall mining operations.

Jan 1, 1990

By David Cronan

"Most of the recent renewed interest in manganese nodule mining has been focused in the Clarion-Clipperton Zone (CCZ) in the NE tropical Pacific where nodules are rich in Mn, Ni and Cu. However, equally interesting, but compositionally different, nodules occur in the tropical central South Pacific (CSP). The CC Zone deposits lie in the International Seabed Area whereas those in the South Pacific lie mainly in the Exclusive Economic Zones of Island States, principally the Cook Islands and Kiribati. The CSP nodules should not be regarded as an alternative resource to CCZ nodules, as they are enriched in different elements. Rather, the CCZ nodules should be thought of as a source of one group of metals (Mn, Ni and Cu) and the CSP nodules the source of another group (see below), mutually complementing each other and to be mined in parallel for their different metals.Manganese nodule mining in the South Pacific has been mooted since the 1970s. However, new data on manganese nodule composition and abundance there have recently appeared. Also, a recently developed interest in 'rare', 'green' and 'technology' elements has necessitated a re-examination of old South Pacific nodule data for information on these elements (previously thought to be economically unimportant), and the re-analysis of the deposits to obtain new data on them. Additionally, current and possibly future applications to the UN to extend island 'continental shelf' areas necessitates an appraisal of the manganese nodules in these areas. These developments have prompted recent work that has helped to refine our understanding of the distribution and abundance of metals of traditional interest in South Pacific nodules, namely Mn, Co, Ni and Cu, but has also drawn attention to other elements of possible economic interest including titanium (Ti), vanadium (V) and the rare earth elements (REE)."

Sep 1, 2014

Outokumpu Technology’s HSC Chemistry process calculation software enables the user to simulate an entire chemical or physical process. The HSC Chemistry 6.0 contains 21 calculation modules and 11 databases for reaction, equilibrium, heat balance, heat transfer, petrological and simulation applications. Most of the calculation modules automatically utilize the same extensive thermochemical database which contains enthalpy (H), entropy (S) and heat capacity (C) data. This database has been expanded to include more than 20,000 species.

Jan 1, 2007