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By J. R. Heberger, B. H. Ngo

The Safety Pays in Mining v2.0 web application, developed by the National Institute for Occupational Safety and Health (NIOSH) Mining Program, helps mines determine the potential costs associated with mining injuries. This web app categorizes injury cost by part of body injured, by the cause of the injury, or by the nature of the injury. When the user selects one of over 150 common types of mining injuries, the app provides information on the distribution of costs of workers’ compensation claims for that type of injury. Based on other user inputs, Safety Pays in Mining v2.0 will estimate the total costs of the selected injuries and the estimated impact of total injury costs on mining company profits and will provide some examples of services and personal protective equipment on which companies could spend the savings that result from the prevention of injuries. This paper reviews the Safety Pays in Mining version 2.0 web application by discussing the development and updates to the app, how it is used to show the true costs of mining injuries, and how mines can benefit from using this app.

Feb 1, 2024

By W. E. Sabina

In the short period of one mans? career we have seen specifications for bulk material handling systems and equipment grow from two or three pages to as much as two or three volumes for a single contract. The old 'short form' described what the purchaser expected the equipment to do. The long form does the same but also includes nut, bolt, and lockwasher depth of detail. What are the events that led to this proliferation of verbiage, and does it benefit the buyer in the final analysis? Is there a better way to purchase complex equipment while ensuring the highest quality for the dollar spent?

Jan 1, 1986

By Bernhard Leist, William D. Leech, Johann Kröyer, Holger Evers

Landsvirkjun—the national electric power company of Iceland—is building the Kárahnjúkar Hydroelectric Project in eastern Iceland. Two glacial river systems will be dammed and channeled through a series of tunnels into a 690 MW underground powerhouse. The Project has a total of 73 km of tunnels to be excavated of which mosthave been completed. From three access adits, three large diameter (7.2 m to 7.6 m),main-beam, gripper-type, Tunnel Boring Machines (TBMs) are being used to complete50-km of the waterway tunnel. Using the TBMs was a first in Iceland to excavate the complex Icelandic basalt formations, which consist of inclined layers of hard basaltic flows with weaker scoriaceous and sedimentary interbeds. Faults, fissures and dykes that frequently cross the lava flows posed both geologic and hydrogeologic difficulties to the TBM tunneling. This paper describes the extreme challenges that the men and equipment had to endure to complete the tunneling, including the harsh winter weather on the surface and the cold, abundant ground water inflows within the tunnels.

Jan 1, 2007

By Christoph Mueller, Grzegorz Tabak

Basing on five years of experience, this paper discusses modern e-drive systems used in underground transport. This covers Energy distribution and cabling principles, inverters and motors as well as auxiliary aggregates. Also an overview of different regimes for battery charging and the energy management and the method of control of the traction are lined out: This means that throttle and brake are not handled separately, but integrated into “longitudinal control” algorithms which assure that a commanded speed is maintained while synchronizing the multi motor systems and taking into account the constraints imposed by e.g. slope grade and battery parameters.

Jun 25, 2023

By Richard Adsero

The Australian Bureau of Statistics and the United States Bureau of Labor Statistics publish data for a range of industries, allowing a measure of performance to be quantified, called multifactor productivity (MFP), and allowing performance between industries to be compared on a consistent basis. At the time of writing, the last released data was for 2011-2012. For Australia, the plot of mining industry productivity and a basket of the 12 most significant industries in Australia?s economy (including mining) are shown in Fig. 1. For the United States, mining and petroleum and all manufacturing productivity are also displayed in Fig. 1. The trends are as follows: ? The MFP in the Australian mining sector rose 36 percent from 1986-1987 to 2000-2001. There was a 47-percent decline in MFP from 2000-2001 to 2011-2012 (Australian Bureau of Statistics, 2011). ? The MFP in the United States mining sector rose 17 percent from 1986-1987 to 2004-2005. There was a 7-percent decline in MFP 2004-2005 to 2010-2011, (Topp et al., 2008).

Sep 1, 2013

By Chunbao Sun, Qi Liu, Chao Wang

Entrainment is a process by which fine and ultrafine particles are transferred to the flotation froth from the top of the flotation pulp, and eventually discharge to the concentrate product, evenwhen they are not attached to gas bubbles. Therefore, entrainment can be considered as a two-step process, one at the upper layer of the pulp to the flotation froth, and the other from froth to the concentrate. Entrainment is inevitable for both hydrophobic and hydrophilic minerals and is one of the significant factors affecting concentrate grade. This paper provides a comprehensive review of the entrainment mechanisms and entrainment models, as well as a summary of the main factors affecting entrainment and the techniques thatmay be used to lower or eliminate entrainment. Based on the review, we point out that selective aggregation of fine and ultrafine gangue minerals using appropriate process aids (polymeric depressants, inorganic salts, etc.) to increase their particle sizes appears to be a convenient and economical method. Directions of further research along this line are discussed.

Aug 31, 2020

By Eugene A. Lang

Mr. Chairman, ladies and gentlemen. As a member of the uranium and coal producing community, I am pleased to participate in a session dedicated to a look at these and other mineral markets.(title slide) before sharing some of my thoughts with you, let me tell you a little bit about rocky mountain energy company. It was established as a subsidiary of union pacific corporation in 1971 with responsibility for coal, uranium, and industrial minerals. We participate in four coal mining operations and a uranium mine and mill all in Wyoming, and an aggregate and an abrasive operation in Utah.

Jan 1, 1984

By B. K. Belle

The use of diesel engine locomotives in South African mines can be traced to Van Dyk Consolidated Mines Ltd on the Witwatersrand gold mines in 1928 as a replacement for battery locomotives. The advantages and disadvantages were recognized in those days, and surprisingly, there are no significant additions to this list, but only refinements. In the absence of any Occupational Exposure Limit (OEL) for Diesel Particulate Matter (DPM) in SA, the Mine Safety and Health Administration (USA) rule is currently being used as a benchmark for the ventilation engineering designs. This paper discusses the ongoing SA journey of measurement and limitations of exposure data for ventilation planning and regulatory purposes. The currently accepted DPM limits are based upon the belief that they are economically and technically feasible for the mines to reach and are not necessarily health based. For SA underground platinum mines, a median TC/EC ratio of 1.8 with a range of 1.2 to 5.8 was observed. For SA coal mines, a median TC/EC ratio of 1.44 with a range of 1.25 to 2.13 was observed. While it is common practice in the USA to use the ratio of TC/EC for metal mines to be 1.3, the ratio found in local platinum mines is 2.2 and for coal mines, the ratio was 1.53 which is lower than Australian studies, i.e., 1.96. It has been shown that a need for critical analysis of TC/EC ratios exists, and possible reasons for variance must be understood before stringent adoption of overseas recommended limits for DPM. It is hoped that the findings from this paper would provide input to scientific approaches in developing appropriate conversion factors, limits for DPM and also in ensuring appropriate error factors (currently 1.14 for TC and 1.2 for EC) for compliance determination.

Jan 1, 2009

By D. M. Abbott

The requirements of the International Mineral Property Valuation Standards Template (IMVAL Template) (includes Petroleum), 4th edition of April 14, 2021, are based on six principles: 2.1.1 competence, 2.1.2 materiality, 2.1.3 transparency, 2.1.4 objectivity, 2.1.5 independence, and 2.1.6 reasonableness. The IMVAL Template describes “reasonableness” as, “The Valuer must ensure the Reasonableness of the Valuation. Any Valuation, assumptions applied, and any method relied upon should be reasonable within the context of the purpose of the Valuation and the Basis of Value. A method applied to the subject Mineral Property should be within the expected capability and consideration of an assumed likely buyer or lessee of the property.” The IMVAL Template’s Guidance 3.6 on Reasonableness states, “The test of Reasonableness is to consider what appropriately qualified and experienced Valuers, acting reasonably, would conclude in the circumstances. The Valuer must form an opinion that is reasonable in the circumstances, that is, what a Valuer believes is rational and plausible in the circumstances and would be viewed as such if considered by other appropriately qualified and experienced Valuers with the same information and at the same time.” Finally, the IMVAL Template’s Definition 4.26 states Reasonableness “[m]eans that other qualified and experienced Valuers with access to the same information for the same Valuation Date and Basis of Value would consider the Valuer's estimate of Value to be within a reasonable range.”

Mar 2, 2022

By William Gleason

During the past five years, mining operations have had access to press technology for piping and joint fittings that can save owners a significant amount of time when installing or replacing pipes by eliminating the need for welding or threading. Viega, with North American headquarters in Wichita, KA, entered the mining sector in 2009, adding to its already expanding industrial sector. Since then, the company?s global engineering department has paid considerable attention to its industrial division, bringing its expertise in plumbing solutions for residential and commercial buildings to the mining and mineral extraction industry. ?We have a lot of applications in the mining industry.?We have a lot of applications in the mining industry throughout the United States, Canada and Mexico and continue to expand in the mining industry,? Tom Shields, Viega?s director for industrial accounts explained. ?Since we made the decision to increase our presence in the industrial markets, we have been aggressive and more than 240 applications have been approved by our engineering department in Germany.? Getting approval from Viega?s engineering department is no small feat. During a tour of the manufacturing facilities in Ennest and Großheringen, Germany, Mining Engineering, as well as a select few other publications and clients, were shown Viega?s manufacturing process. At the Ennest facility, hundreds of millions of fittings are produced, and each one is inspected mechanically and with a laser at the end of the production line. With four production facilities in Germany and one in the United States, Viega is able to ship to anywhere in the world. The company distributes everything from fittings to stainless steel pipe.

By Dapeng Zhang, Brij Moudgil, Shibo Zheng, Chunhui Feng, Wenyi Song, Wending Xiao, Patrick Zhang

Separation of dolomite from phosphate is the most challenging problem in phosphate mineral processing. Over 50% of the future phosphate reserve in Florida contains too much dolomite to process using the current industry practice. The current phosphoric acid production practice requires less than 1% MgO in the phosphate concentrate as the feed material. The Florida Industrial and Phosphate (FIPR) Institute has collaborated with worldwide experts in the field to address this issue. As a result, the industry is now offered three feasible options. Option 1 offers three methods for reducing MgO content in the concentrate from the Crago process, including adding a dolomite depressant in the rougher flotation step, dolomite flotation of the cleaner concentrate, and scrubbing the cleaner concentrate in quartz sand. These methods could reduce MgO content in the final concentrate by 20–40%. Option 2 involves crushing and grinding of high-dolomite phosphate pebbles followed by dolomite flotation at slightly acidic pH using a new collector that does not require phosphoric acid as a phosphate depressant, achieving a final concentrate analyzing less than 0.9% MgO at about 87% P2O5 recovery. Option 3 is a gravity separation technique using an innovative separation jig, and its full potential remains to be demonstrated.

By Patrick B. Kenny

Generally speaking, it is safe to address this conference as a conclave of Engineers, Owners' Agents, Governmental Representatives, and Contractors. As a group, we have assembled here to learn of our compatriots engaged in similiar underground operations throughout the United States and the World. We are here to learn of improved methods, higher technology, and better management. Through the acquisition of this knowledge, we each hope we can improve our own particular services, products and projects. This session is dedicated to a discussion of "Costs". The most apparent reason for a discussion of costs at this level is to expose subjects affecting costs and propose methods to reduce them. From that premise a contractor can identify three areas of discussion: design considerations, contract considerations, and governmental considerations. A fourth area of consideration is an introspective view of the contractor's role in the design construct process. Unnecessary costs and risks attributable to these areas are contributing excessively to ever increasing project and system costs. DESIGN CONSIDERATIONS On April 20, 1977 the Metropolitan Sanitary District of Greater Chicago accepted proposals for the Tunnel and Reservoir Plan on Contract A and Contract B. This letting called for construction of over 33 km (21 miles) of the Mainstream Tunnel bored at 9.75 m (32 ft) to 10.67 m (35 ft.) in diameter. Also included were all the appurtenant collecting and regulating structures. The proposal allowed the

Jan 1, 1979

By Jamal Rostami, Ebrahim Farrokh

Selection of tunneling method, specially the use of shielded machines for application in deep rock tunnels can be heavily impacted by presence of ground convergence and squeezing conditions. Tunnel convergence is a function of ground conditions (i.e., rock mass behavior, groundwater, in-situ stresses), size of the opening, and TBM operational parameters. The case study of Ghomroud water conveyance tunnel project in Central Iran, which is under construction using a double shield TBM, is used to examine the effect of rock parameters on tunnel convergence and hence on the need for over excavation and shield lubrication to avoid problems with the shield getting stuck. Although it is impractical to perform a continuous assessment of rock mass conditions within the shield or in the lined tunnel, results of field observations and subsequent studies show that the amount of the tunnel convergence has direct correlation with the percentage of fines and large rock fragments in the muck and TBM thrust/torque/ROP. These relationships have been examined and will be presented in this paper.

Jan 1, 2007

By W. H. Pomroy

In its 2001 diesel particulate matter (DPM) rule for metal and nonmetal underground mines, MSHA established an interim concentration limit of 400 micrograms of total carbon (TC) per cubic meter of air (400TCµg/m3), and a final concentration limit of 160TCµg/m3, to be phased in over five years. Following a court challenge to the 2001 rule, MSHA, industry and organized labor reached a partial settlement of the litigation under which the agency agreed to issue a proposal to amend the 2001 rule by, among other things, changing the surrogate from TC to elemental carbon (EC), applying MSHA's traditional hierarchy of controls, and revising requirements for one-year special extensions for complying with the final DPM exposure limit. MSHA issued a final rule in 2005 converting the interim concentration limit from 400TCµg/m3 to 308 micrograms of EC per cubic meter of air (308ECµg/m3) based on a miner?s personal exposure. Pending further rulemaking, MSHA retained the final concentration limit of 160TCµg/m3. In May 2006, MSHA issued a final rule that clarified that the final limit of 160TCµg/m3 would be based on a miner?s personal exposure rather than as a concentration limit. The 2006 rule also phased in the final DPM limit in three steps over two years, beginning in May 2006 at 308ECµg/m3, followed eight months later in January 2007 with a limit of 350TCµg/m3, and finally reaching 160TCµg/m3 in May 2008. Also in the 2006 rule, MSHA committed to converting the 160TCµg/m3 limit to an EC limit in future rulemaking. This paper reviews the DPM exposure limits in the context of the MSHA rulemakings and discusses the DPM engineering controls that were utilized by mine operators to attain compliance with each progressively lower limit.

Jan 1, 2009

By Theodore S. Jordan

The discovery of a major porphyry-type copper deposit on the Papago Indian Reservation in Pinal County, Arizona was announced by El Paso Natural Gas Company in 1968. The deposit, known as the Lakeshore Property, contained an estimated 470 million tons of sulfides and oxides averaging 0.75 percent copper. History and Geology of the area have been described by Harper and Reynolds (1969). El Paso subsequently&apos; entered into the agreement for joint development of the property with Hecla Mining Company, with Hecla as the operator. The ore body consisted of three types of mineralization: 1) Disseminated Oxide Ore, <1% Cu 2) Disseminated Sulfide Ore, <1% Cu 3) Tactite Ore, >1% Cu

Jan 1, 1985

By T. C. Souza Pinto

Because shape is an assessment of the three-dimensional form of a particle, it may be described in terms of sphericity (?), which is a measure of how closely a particle approaches a spherical configuration. In this study, Darcy?s law and the Kozeny-Carman model for fluid flow through porous media were applied to packed beds to determine the sphericity (?) of apatite particles. The beds were composed of glass spheres or particles of apatite (igneous from Brazil and sedimentary from the United States) of three classes of size (Class 1: -297 +210 µm; Class 2: -210 +149 µm; Class 3: -149 +105 µm). Glass spheres were used to validate the model because of its known sphericity (? = 1.00). Apatite particles, either igneous or sedimentary, showed very close values for particle sphericity (? ? 0.6). Observations on particle images conducted by scanning electron microscopy illustrated that igneous (? = 0.623) and sedimentary (? = 0.644) particles of apatite of Class 2 predominantly exhibit elongated shape. The close value of particle sphericity (? ? 0.6) showed by either igneous or sedimentary apatite may be justified by the similarity in particle shape.

Jan 1, 2009

The occlusion of unliberated gold particles in silicates and sulfides in crushed/milled ore dictates the recovery that can be expected. The grade of this occluded gold in cyanide leach residues shows a consistent, general relationship to the head grade of the ore, irrespective of mineralogy or geographical location. The residue grade almost invariably increases with the head grade, but not in proportion to it. This phenomenon appears to stem from the nature of the geological events originally responsible for creating the ore deposits. A statistically-based technique for determining the true head grade-tail grade relationship from gold plant operating data is described. The effect is illustrated with results from several worldwide gold milling operations analyzed over the last 35 years.

Jan 1, 2008

By J. L. Whitlock

A mutant strain of Pseudomonas paucimobilis is utilized to effectively degrade and or remove 90-98% of cyanide, thiocyanate, toxic heavy metals and ammonia from a cyanidation mill process and mine discharge maximum of 21,000 m3/d (5.5 MGD). Homestake Mining Company?s biological wastewater treatment plant has been in full scale operation for over 2 years at the Homestake Mine in Lead, South Dakota.

Jan 1, 1987

By K. Y. Vasioutchkov, Y. F. Vasyuchkov, B. M. Vorobjev

In general a term "unconventional mining or "non-traditional mining technology" getting more and move familiar to the mining engineering media. There are several alternating terminological combinations such as "in situ mining", "borehole mining", "shaftless mining", "mineless mining", "geotechnology" etc.; specific terms denote particular method of unconventional mining technology: "underground coal gasification in situ", "underground coal combustion in situ", "borehole hydraulic coal mining" and others. Principal scheme of unconventional coal mining technology is shown in [Figure 1:] One of the greatest potential for coal utilisation during the beginning decades of on coming cetury is the synthetic fuel-gas derived from coal as a product of coal gasification. It is quite logical to enrich this gas before burning it with natural gas, that is methane, contained in coal measures. Thus it is reasonable to suggest a new concept of unconventional coal mining and utilization technology featuring integrated methane drainage with coal-gas combined cycle. Proposed unconventional technology of coal mining is characterized with: - opening up a coat deposit through boreholes, drilled from the surface and used for coalbed methane drainage as well as for coat gasification in situ; - aggregation of methane producing and coal gasification station on mining side with thermo power plant on the electric power generation side in one integrated industrial enterprise. The further improvement of the conventional coal mining technologies both surface and underground could give only insignificant results in economical, ecological and social aspects, but would not be able to provide basic requirements of the XXI-st century. Significant increase in economical efficiency, cardinal humanization of coal mining and basic improvements in environment protection would be achieved through introduction and implementation of innovative or unconventional coal mining technology. These considerations are applied on both coal production and coal utilization sides as far as coat based energy generation is concerned. Now a general opinion is widely spread that an application in the same manner of the traditional technologies of coal mining and electric power generation would inevitably cause further irreversible damage of the global eco-system, notwithstanding the certain environment protection measures being taken. Keeping the recent pace of the eco-system degradation the whole our civilization would be in danger. Thus the solution of this problem is to be found in developing, promoting and implementing in industry unconventional coal mining and modern advanced clean coal technologies. Coal reserves with favourable conditions at shallow depths are -being rapidly depleted in all countries with developed coal industry. So in nearest future more coat will be mined from deeper levels with higher operational expences and with lower labour productivity. For example in Russia only 20% of proven coal reserves can be specified in quality as easy mined reserves, i.e. coal reserves with a good minability. Unconventional (borehole in situ) coal mining enables us to mine difficult coal reserves, deposited under unfavourable geological conditions with higher economical and socio-ecological efficiency than that in conventional coal mining, in view of these the basic principles and concepts of coal mining and coal utilization for energy generation should be reconsidered taking into account the latest achievments in underground coal gasification/combustion, coalbed methane extraction, clean coat technology and advanced developments in environmental engineering. The authors have developed a new concept of ecologically clean and resource saving coal-gas electricity, protected by a patent of Russian Federation (1995). The main principles and technological features of these conceptual technologies are explained hereupon. It should be a break through into a coal mining technology of new generation, which is known as unconventional coal mining technology. Under current global energy policy, transection to the new generation of coal mining technology is inevitable. Now we are standing at the treshhold of the coat&apos;s regeneration based on integrated unconventional coal mining and innovative coal fueled electric generation technologies.

Feb 24, 1997

By O. V. Bush

Most governments recognize that energy efficiency represents a partial solution to reducing global capital shortages and environmental crises that threaten to seriously impede economic growth. Much of the United States and many foreign countries are embracing the concept of Integrated Resource Planning (IRP) which incorporates Supply Side Management (SSM) and Demand Side Management (DSM). Since SSM comes at twice to three times the cost of DSM, it makes economic sense to employ the energy conservation techniques of DSM. This paper will explain these concepts and some of the incentives being put forward by governments and utilities to promote DSM.

Jan 1, 1995