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By J. Wiebmer

Some thoroughbred racehorses are great routers (distance runners), others are sprinters. Some racehorses perform best on turf, others on dirt, and some in mud. To be a winner, you have to choose the right horse for the course. It's no different when looking at an electric cable shovel, a hydraulic shovel/excavator, or a wheel loader. Each loading tool has its own zone of application. To be a winner, you have to choose the right horse for your course.

Jan 1, 1993

By D. C. Edwards

In an age where customer service and quality drive today's industry and business, no service or product is exempt from these demands. Industry and business are streamlining everything from people to equipment and today have a heavier reliance on the performance and quality of their assets and equipment, (one of the keys to staying competitive). In the mining process industry, the centrifugal slurry pump is a key piece of equipment that keeps product moving and aids in generating revenue for its owner. The continued improvement and customer success lies in a team effort between the mining industry and the pump manufacturers. We, the pump manufacturers, need to keep improving our designs to further extend the life of our pump with fewer failures and promote to our customers proper maintenance of the pumps to continually keep unexpected failures to a minimum. Strict equipment maintenance, as thoroughly demonstrated by the military, is key to the long life and success of any piece of equipment. In the often harsh duty of the centrifugal slurry pump, maintenance is something that requires "attention to detail". No area of the pump is exempt from attentive maintenance. Here, discussions will focus on the areas of the mechanical drive end, wet end, seals, and extended pump shut down and start up. There has not been a slurry pump designed to maintain or repair itself. So in effect, each pump warrants able bodied maintenance persons to maintain them who continually observe all the rules of safety. Prior to any maintenance discussion or action, the issue of safety should always be addressed. Here, as with everywhere, the same rules apply. Work at a safe pace, note all safety precautions, use associated safety equipment and personal protective attire, observe all tagout and lockout procedures, and most importantly, be aware.

Jan 1, 1996

By B. DANIEL MARJAVAARA, I. A. SOFIA LARSSON, ANNA-LENA LJUNG

One way to upgrade iron ore is to process it into pellets. The pelletizing process is multifaceted, involving complex fluid dynamics with highly turbulent, high-temperature flow in intricate geometries. This makes it hard to perform measurements during operation, so a useful tool for better process understanding is computational fluid dynamics (CFD), where the challenge is to perform efficient and trustful simulations of complicated problems. A validated simulation model can be valuable for increased process control and development. In this paper, the flow field and coal combustion process in a pilot-scale iron-ore pelletizing kiln is simulated using a CFD model. The objective of this work is to apply a coal combustion model to enable an investigation of thermal effects from the flame on the surrounding flow field.

By Barbara B. Newlin, Emily Rosenberg, Marianne Snedeker

Whose longwalls perform best in Eastern underground mines? What is the latest legislation affecting slurry pipelines? What are the trace element constraints on magma genesis? How can process set points be controlled more economically without affecting product quality? Where can I get a paper presented at the Australian Coal Preparation Conference? If answers to questions like these can help with your management decisions, exploration plans, or market positioning, your firm should know about Information on Demand. Information on Demand, Inc. (IOD) is a research service available to SME members to help them get the facts needed to develop business plans. IOD can function as a research staff and data bank specialist for geologists, planning specialists, production managers, and engineers in all levels of the mining industry. Just dial 415-549-3259 and ask IOD for a copy of an obscure article, a comprehensive literature search, or a background report on a company, a process, or a product. Within a short time, IOD will have the information you need delivered to your office or worksite. Information on Demand has a bank of dial-up terminals that provide access to more than 200 business and technical data bases, including Lockheed's Dialog, CompuServe, InfoLine, The New York Times Information Bank, and other systems. These data banks contain more than 95% of the world's technical literature published in the last 10 years. There is no input required from individuals or companies. The data bases are maintained by publishers and are constantly updated with abstracts of articles, reports and reviews, and other text appearing in more than 5,000 engineering publications, as well as thousands of other trade and technical publications. The data bases are organized by subject and offer a speedy comprehensive survey of world literature. One data base, called Compendex, provides worldwide coverage of engineering publications, meetings, and reports. The Metadex data base abstracts literature on the science and practice of metallurgy, and can be accessed by commercial, compositional, and numerical alloy designations. PatSearch and Claims data bases enable IOD to determine what patents have been filed by a given entity, what international patents are equivalent to a US patent, and other vital patent information. In the non-technical arena, the Commerce Business Daily has daily updates of federal procurement information. The Federal Register is abstracted on-line in a data base, and ABI/Inform is a data base full of marketing and management information for all industries. IOD offers a free pamphlet listing these and other data bases. A typical literature search from IOD will produce 60-200 references with abstracts, and can be printed out off-line and mailed or transmitted directly to an electronic mailbox. Abstracts will often give all the information needed by the reader. At times, when the complete article or technical report is needed for further study, IOD will send a photocopy of the full text for a small additional fee. Patents, books, securities exchange filings, standards, and specifications can also be supplied by means of IOD's network in major libraries, such as Harvard, MIT, and The Library of Congress. A technical translation service is available for foreign

Jan 12, 1983

By Jackson M. Langton

INTRODUCTION The Morenci-Metcalf district is located on the southern slope of the white Mountains in Greenlee County, Arizona. Both porphyry copper deposits are four to six miles northwest of Clifton, the county seat, and the new Metcalf mine is situated approximately one mile northeast of the Morenci open pit (Figure 1). Chase Creek, a south-flowing tributary of the San Francisco River, dissects the district and separates the two ore bodies. More than 1,200 exploration and development drill holes have been completed in the district and the Morenci-Metcalf ore bodies have been delineated on a 400-foot grid. Recently initiated drilling programs have revealed new data about deeper protore and associated hypogene alteration. This information, correlated with surface mapping and petrographic studies, was utilized to propose a plausible geochronologic sequence for this region. The reasoning behind this study has been helpful in locating new ore beneath leached capping indicative of only protore mineralization. The scope of this paper is to establish a practical solution to a highly theoretical problem of ore genesis and to familiarize the reader with stratigraphic, structural, and mineralogic events responsible for localizing ore in this district. Continued research will possibly alter the proposed time span and relative displacements, but it is doubtful that the order of events will vary significantly. Geochronologic conclusions are therefore presented as general hypotheses and additional geologic mapping,

Jan 1, 1972

By E. Watkins, S. J. Schatzel, K. Ajayi, V. Gangrade

The National Institute for Occupational Safety and Health (NIOSH) has been conducting research related to unconventional gas wells positioned in abutment pillars associated with active longwall mining in Southwestern PA. The Ventilation and Explosion Prevention Team at NIOSH is working toward predicting and characterizing a hypothetical casing breach and its effect on the safety and health of mine workers, gas well workers, and the general public. An important aspect of this research is to distinguish coalbed gas from shale gas in the mine environment as an indicator of a casing breach. Another noncoal gas source exists in the region in the form of underground gas storage fields which also have the potential to migrate towards mine workings. During a potential gas breach, the addition of excess natural gas to coal mine environments will exceed the anticipated ventilation loading and can create a mine explosion hazard. A methodology has been developed to distinguish these gas sources. Gas samples from the three sources were analyzed by gas chromatography, and interpretive methods were applied to distinguish the populations graphically and statistically. Bivariate plots using the hydrocarbon index and the normalized molecular ratios showed that the sources occupy different regions of the graphs. All samples of non-coal gas contained under 2% CO2, and all coal samples included greater than this amount. A multivariate T-squared (T2) test analysis relating comparing data in pairs showed a low p-value (dimensionality parameter) and a high T2 test statistic for all comparisons, indicating that these sources are different and distinct gas populations. Ultimately, stakeholders from the mining and gas production industries can utilize this method to identify gas sources and a potential casing breach.

Mar 2, 2022

By R. M. Barker

The historic Getchell property is currently being mined from the Getchell Main Underground workings, a foot wall extension of the Getchell open pit deposits along the Getchell fault. Drift-and-fill techniques are used to extract the ore through a ramp access. The adjacent Turquoise Ridge deposit is currently under development via two vertical shafts. Together, the two mines will continue to provide feed to the Getchell's 3,200 tpd mill/autoclave circuit, taking Getchell Gold from its current production rate of 200,000 ounces (Au) per annum, to over 400,000 ounces (Au) per annum by 1999.

Jan 1, 1997

By Patrick Sullivan

Over the past few years, successful operations for processing phosphates employing the Grate-Kiln System have been achieved. Control and instrumentation philosophy followed in these installations are described and analyzed. Concepts utilizing digital techniques and computer systems appropriate for similar installations are also discussed.

Jan 1, 1967

By James M. Link

The transportation of solids by slurry pipeline is a rapidly growing field. Although early patents date from the latter part of the nineteenth century, it has only been within the last twenty years that successful long distance slurry transport lines have come into their own. The pioneering efforts in this country include the gilsonite slurry pipeline from Bonanza, Utah, to Grand Junction, Colorado, and the coal slurry pipeline from Cadiz to Cleveland, Ohio. Both of these lines were constructed in 1957 and had a combined annual capacity of about 360 million ton miles. Although the Cadiz pipeline was mothballed in the early 1960's, the interest in slurry transport systems continues to increase and one engineering and construction company is predicting that by 1980 an annual slurry system rate of more than eight billion ton miles will be achieved. The design and construction of cross-country pipelines for fluids such as crude oil appears relatively simple when contrasted against the complex problems encountered in slurry systems. Considerable effort has been expended in hydraulic research laboratories in an attempt to improve our understanding of slurry behavior. This effort has been rewarded with considerable success and is best illustrated by the large number of slurry systems now planned or under construction. However, slurry transport in pipelines is still, in many instance more of an art than a science. In order to minimize the risk factors in the construction and operation of large scale slurry systems, studies are frequently conducted in pilot scale test

Jan 1, 1972

By J. R. Patts, L. D. Patts, S. J. Janisko, T. Barone

"Controlling float coal dust in underground coal mines before dispersal into the general airstream can reduce the risk of mine explosions while potentially achieving a more efficient and effective use of rock dust. A prototype, flooded-bed scrubber was evaluated for float coal dust control in the return of a continuous miner section. The scrubber was installed in line between the ventilation tubing and an exhausting auxiliary fan. Airborne and deposited dust mass measurements were collected over a period of three days at set distances from the fan exhaust to assess the changes in float coal dust levels in the return due to the operation of the scrubber. Mass-based measurements were collected on a per-cut basis and were normalized per foot of advance by the continuous miner. Results show that average float coal dust levels measured under baseline conditions were reduced by over 91% when operating the scrubber. INTRODUCTION In 2012, underground mining in the United States produced over 342 million tons of coal [EIA 2013]. During the cutting, crushing, and transport of this coal, dust is generated and can be entrained in the air ventilating the mine. Title 30 Code of Federal Regulations Part 75.400-1 (30 CFR§ 75.400-1) defines float coal dust as particles of coal that can pass a No. 200 sieve. These coal particles can be carried by the ventilating air into return entries before settling onto mine surfaces [NIOSH 2006]. If this float coal dust becomes re-entrained into the airstream, it can propagate an explosion throughout mine workings [Harris et al. 2010]. Application of rock dust in underground coal mines is required by Federal regulation as a means of preventing the propagation of explosions by float coal dust. In order to meet Title 30 Code of Federal Regulations Part 75.403 (30 CFR § 75.403), 80% incombustible content must be maintained in the composition of dust deposited in mine entries [76 Fed. Reg. 35968 (2011)]. This fraction of incombustible content is increased if elevated levels of methane are present. In order to maintain the required incombustible content, frequent or constant application of rock dust is undertaken by mine operators. Title 30 Code of Federal Regulations Part 75.2 (30 CFR § 75.2) defines the properties of the rock dust that must be used by mine operators."

Jan 1, 2015

By A. Heriba

Cyanide is highly toxic to humans and other organisms. Concentrations of RCN as low as 0.05 ppm can be lethal to fish (Scott and Ingle', 1981). In wet climates and in colder climates where natural degradation is slow, it is becoming mandatory to destroy cyanides in effluents before they can be discharged. The disposal of spent gold ore as tailings from cyanide heap leach processing facilities is a matter of concern to the public, the mining industry, and regulatory agencies. South Dakota mining laws and regulations require that spent ore be neutralized to a suitable level with respect to cyanide before disposal (Durkin, 1990). To safeguard the environment and protect ground-water and surface-water supplies adequately, a reliable test is needed to determine the amount of cyanide in the solid spent ore.

Jan 1, 1993

By G. Bylapudi, A. Bhagwat, K. Mondal, A. J. S. (Sam) Spearing

Minimizing the effects of corrosion improves the long-term performance of the rock anchors and ground control systems in underground mines, which is fundamental for safe operation over the design period. The primary objective of this study is to explain the problems due to stress corrosion cracking (SCC), strain-induced corrosion cracking (SICC) and other forms of corrosion, and why the mining industry’s ground control professionals should take this into serious consideration. It is important to clearly determine the kind of SCC mechanisms that causes roof bolt failures in order to suggest the necessary action plan to mitigate or eliminate the possibility of the cause. Pertinent literature and studies around the globe on this complicated subject are reviewed. The secondary objective is to encourage the use of corrosion-resistant ground control products in the underground mining industry in areas of high corrosion potential. Characteristics of SCC on high strength steel are also reviewed. The literature and preliminary studies to date indicate that research work is necessary in United States.

Jan 1, 2015

By R. L. Taylor, S. D. Abbott

"INTRODUCTION Mines are filled with a mixture of gases, some of which are toxic, flammable, explosive. Others can be early reporters of potential problems. It has previously been shown that analysis by gas chromatograph can the most accurate conventional analytical tool for common mine gas mixtures when used correctly. There are some other detection methods (e.g hand held sensors), but they do not detect many situations which are immediately dangerous to life or health (IDLH). Examples include explosive hydrogen mixtures, toxic carbon dioxide levels, and some explosive mixtures of methane with oxygen. (Reference our previous paper). There are several reasons for mines to consider onsite GC analysis. (1) Timeliness of results. Samples can be taken and analyzed immediately. Samples do not have to be shipped to a lab and wait for results. (2) Ability to run greater number of samples a lower for the same cost. This allows mine to increase the number of samples taken to be more informed about the gases/conditions of the mine without the worry of financial constraints. (3) Fewer sample media needed, and there is no wear and tear or cost from shipping them offsite. When samples are shipped offsite, those sample media cannot be used to take until the lab returns them when the analysis is done onsite, the sample media can be used again almost immediately. However there are several challenges associated with using GC to analyze mine gas samples onsite. To date there has been a clash of the requirements for a successful analysis, the capabilities of the technology, and the practicalities of implementation. The purpose of this paper is to discuss some of the difficulties in getting accurate reliable data and doing so in an economic way. This whole measurement activity is a cost center for a mine, so there are economic concerns for the mine to address. These concerns are mainly staffing costs, capital costs, maintenance, and consumables costs. A properly staffed and equipped analysis lab, including burdened overhead, costs about $500K per year. At a sampling rate of 10 per day, this is about $140 per measurement for a proper onsite lab."

Jan 1, 2016

By W. R. Hail

A proactive design and construct approach was used to remediate the Warm Springs Ponds Complex near Anaconda, Montana under "Superfund". The pond complex is used for treatment/settlement of heavy metals and is a repository for 19,000,000 cubic yards of tailings, precipitates and associated sediments. Remediation has resulted in treatment/settling capacity for flows up to the 100-year flood (3,300 cfs); expansion from 5 to 11 ponds in series requiring 12.5 miles of new or improved embankments with associated hydraulic structures; flood protection for the 0.5 Probable Maximum -Flood (PMF) (70,000 cfs); and closure of exposed tailings along with aquatic and terrestrial habitat enhancement.

Jan 1, 1995

By I. A. Tinto

Labrador City is located in the southwestern portion of Newfoundland-Labrador, approximately 965 kilometers north-east of Montreal. The mine and beneficiation complex of the Iron Ore Company of Canada, known as the Carol Project, is situated 535 metres above sea level in a climatic region characterized by cold winters and short, cool summers. History The iron Ore Company of Canada commenced work in the area in 1949, however, it was not until 1958 that the decision was made to proceed with mining operations. The ore body consists of Specular Hematite (Fe203) and Magnetite (Fe304) with small quantities of Limonite and Geothite. The average grade of the ore bodies is 39% iron.

Jan 1, 1985

By V. O. Tenorio, K. P. Hague

Mines are constantly trying to improve production processes by optimizing work cycles, reducing operational delays, minimizing costs, controlling equipment utilization, and preventing occupational hazards. Currently, advances in digital mining technologies within the concepts of 5G and Industrial Touch Internet are allowing better control and monitoring of underground mining equipment, with centralized control systems that unify data analysis for proper decision making. A wireless 5G-based platform for controlling and monitoring systems for underground mine operations can be designed over a comprehensive layout in where bandwidth selection, sensor location, Wi-Fi repeaters and power distribution are put together to build a successful supervisory system. In order to confirm the validation of these concepts, a case study is proposed for a medium-sized underground mine with a multi-level network which includes tablets managed by production supervisors, along with other data collection devices installed in semi-autonomous mining equipment, collecting, and distributing data in near-real time, with interconnection to support and services areas on the surface.

Mar 2, 2022

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 Tomás Vergara, Marcelo Vergara, Alonso Pereira, Fernando Concha, María V. Gutiérrez, Fernando Betancourt

Filtration of copper concentrates in the mining industry is carried out in cycles, mainly cake formation, expression, and blowing. Each of these cycles depends on the solid (mineralogy, porosity, particle size distribution), water, and air (density, viscosity, permeability, and relative permeability) properties that define the performance in each cycle. The fundamental phenomenon in cake formation and expression is a one-phase flow (water) through a porous bed of solid particles (the cake), while in blowing it is a two-phase flow (water and air) through the cake. Sometimes, due to a change in the properties of the mineral, a filtration plant is unable to maintain the capacity at the specified humidity. One alternative to solve this problem is to heat the air during the blowing cycle, which in turn heats the water in the cake, this process significantly decreases the water viscosity and only marginally increases the air viscosity. In this work, this strategy was studied at a laboratory scale. The results show a significant decrease in the blowing time as the temperature of the air was increased.

May 24, 2022

By K. V. Raj

As open pit mines continues to grow deeper, managing air pollution can become challenging. During arctic air inversion, the temperature of the air over the mine increases with altitude, and the cold, heavy, surface air is trapped in the pit. This problem is complex, and any solution will require an extensive understanding of the interactions between the aerodynamic movement of air, air inversion, meteorology, pollutant sources, and transport phenomena in the open pit mines. The availability of computational fluid dynamics (CFD) has elucidated the pollutant flow mechanism in open pit mines. Very few CFD studies have been published, especially the Large Eddy Simulation (LES), on the contaminant transport in deep open pit mines under arctic air inversion. The contaminant transport in an open pit mine under arctic inversion is due to a stable or nocturnal boundary layer in micro-meteorological terms. Understanding the physics of the stable boundary layer (SBL) is relevant to air flow and pollutant transport in deep open pit mines. This paper focuses on a Large Eddy Simulation (WMLES as Sub-Grid Scale Model) modeling of the SBL and pollutant transport in a large open pit mine.

Feb 23, 2014

Coal has traditionally been an integral part of life in Kentucky. Coal mining produces a large part of revenue for the Commonwealth of Kentucky and provides a significant number of jobs to the residents of eastern (less in western) Kentucky. Recently, however, the coal industry of Kentucky has had to endure many hardships. The Clean Air Act set forth sulfur dioxide emission standards which have severely affected much of the coal mining industry in Kentucky, because much of the coal mined in Kentucky has a high sulfur content. In this paper, the background around the effects of Clean Air Act on the coal industry is introduced. The economic and social effects of the Clean Air Act on the Kentucky coal mining are addressed.

Jan 1, 1993