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By M. J. Price

The usage of Geographic Information Systems (GIS) is increasing rapidly throughout the Mining Industry, especially in the Industrial Minerals sector. GIS provides an efficient and robust link between spatial (often CADD) and tabular (database/spreadsheet) components. Mineral economists and corporate planners employ GIS to perform market analyses, to source raw materials, and to schedule and monitor deliveries to customers. Exploration and acquisition groups apply spatial analysis to identify high quality resources that meet economic guidelines. Mining regulators and environmental affairs departments expedite and monitor permitting, environmental compliance, and best management practices reclamation through GIS data management and Electronic Permitting. Operations staffs monitor overburden removal, material extraction, quality control, and stockpile volumes with GIS. This paper summarizes the many aspects of GIS in Industrial Minerals. It also introduces and addresses issues and concerns commonly encountered during a mining GIS implementation.

Jan 1, 2001

By J. L. Yordan, J. Kortmeyer, I. Yildirim

Talc is used to remove stickies from pulp during paper recycling processes. It is well known that the interaction is controlled by the surface chemistry at the talc/water, sticky/water and talc/sticky interfaces. If the interfacial tensions are known, one can calculate the free energies of interaction and hence predict whether the stickies can be removed by talc. In the present work, the surface tensions of several different talc samples were determined using the acid/base theory. The information was then used to determine appropriate interfacial tensions, which in turn were used to determine the free energy of interaction between talc and stickies. It was found that the calculated free energies are much more negative than those between the stickies and other minerals such as calcium carbonate, bentonite clay and kaolin clays.

Jan 1, 2002

By R. Gunda

Due to the rapidly increasing production rates and deepening of mine working areas, there is a drastic rise in the number of thermal issues to be addressed for maintaining a safe mine environment. As high temperatures and humidity in underground mines could affect the health and performance of workers, and ultimately the production rate, it is necessary to provide a properly controlled safe environment. The backfilling of stopes in metal, non-metal mines results in different thermo-physical properties for the hanging, side and foot walls, modeling of which is not provided by any existing mine climate simulation software. This paper presents the modeling of such a single stope using the MULTIFLUX (MF) software, developed at the University of Nevada, Reno. A special case is presented in this paper, where a case study from the Homestake mine in the US with a drift and ramp connected to a stope with high Virgin Rock Temperature (VRT) and various spot heat sources is modeled in MULTIFLUX and CLIMSIM, and the results are compared against each other. Another case is presented in which the stope of the previous case is modeled with walls, each having a different set of thermo-physical properties. These results are compared with the former results to analyze the effect of anisotropic properties.

Jan 1, 2011

By J. Kretschmann, N. Nguyen

"The Vietnamese economic growth of more than 5% per year leads this country to an enormous demand for raw materials. In the duration of ongoing expansion, the big challenge in the coming decades will be to make this process as sustainable as possible when it comes to economic, environmental and social objectives. Risk management especially in occupational safety and health (OSH) in enterprises is one of the most important tools to achieve this aim. But until now, this has not been taken into priority by Vietnamese coal mining enterprises. Main reasons for this situation can be found in deficient legislative conditions and in non-synchronized risk management systems. In contrast, Germany has implemented an adequate legal system and the German mining industry has gained lots of experiences in risk management, especially in occupational safety and health. This paper seeks to point out specific challenges how to improve occupational safety and health in Vietnam by transferring and applying German methods and standards."

Jan 1, 2011

By Deborah A. Peacock

"Outer space technology and exploration have reached a tipping point, so that mining and mineral processing in outer space is now a certainty and not a dream. Several competing companies worldwide are on the way to building spaceships to land on the Moon and eventually mine the Moon and asteroids for volatiles, rare earth metals and Helium-3.The Google Lunar XPrize offers a $30 million prize1. China has recently landed a spacecraft on the Moon. The European Space Agency, with cooperation from the United States, has landed a spacecraft, Philae, on a comet. And, Mars One is planning a one-way trip to establish a settlement of humans on Mars.How and why are the Moon and asteroids and their resources of interest to private space industry companies? Why are the Moon and asteroids viewed as a potential business venue?Geology of the Moon and asteroids — Why do we want to mine there?Space enterprises are actively working toward establishing and operating lunar and asteroid mining locations for resource extraction, resource processing, conversion to salable products and distribution of the products and services in space and to Earth and beyond2.Forty-five years ago, the Apollo manned missions to the Moon returned rocks and regolith to Earth, which were studied and analyzed. What they found was that the Moon contains valuable minerals and resources. These minerals are largely due to meteor and asteroid impacts, which have, over eons, created this mineral-rich regolith. These impacts have occurred on Earth as well, for billions of years, particularly early on in the history of the solar system. However, on Earth, wind, water and vegetation have erased most of these impacts. On the Moon, in contrast, the only weathering is caused by subsequent impacts and the solar wind."

Jan 1, 2017

By Peter K. Mathison

The U. S. Department of Interior, Bureau of Mines (Bureau) is developing a hydrologic monitoring system for in situ leaching operations. A working prototype of this system was installed and tested at the Cyprus Casa Grande copper mine. Requirements specific to in situ leaching operations were identified by researchers. The system has been a useful tool for researchers and for mine personnel. Observations of the hydrologic monitoring system, including details of the development process, the design of the system, and the software developed at the Bureau have resulted in new ideas for an enhanced design of the system.

Jan 1, 1992

By F. M. Doyle

Ion flotation shows great promise for recovering and removing metal ions from dilute process streams, either for environmental compliance or to recover values. This technique uses an ionic collector to concentrate non-surface active colligend ions of the opposite charge from a bulk solution at the solution?vapor interface. With a sufficiently large solution?vapor interfacial area (provided, for example, by sparging gas through the solution), the colligend can be concentrated and removed along with the collector in a foam phase. A key limitation on using the technique in the minerals industry, where many process streams contain a variety of ions and have relatively high ionic strengths, is the need to control which ions are interacting with the collector. Here the effect of three different chelating agents, namely dodecyldiethylenetriamine (Ddien), ethylene diamine tetraacetic acid (EDTA) and triethylenetetraamine (Trien), on the selectivity of copper, nickel and cobalt, or copper and alkaline earth metal ions, is reported. The results are discussed in terms of their implications for adoption in the minerals industry.

Jan 1, 2009

The only significant iron ore deposit in Hungary could be found in Rudabánya. The mine was closed in 1986. The area of Rudabánya was always the home of heavy mining activity. In former times, mainly silver and other non -ferrous metals were excavated.

Jan 1, 2011

By I. Gombköto, J. Bohm

"In Europe, and therefore in Hungary opening a new mine is harder and harder. Depletion of mines, unfavourable legal and economic changes, and growing public concerns are the main reasons. Social and economic interests require total utilization of mineral raw materials of the operating mines, and furthermore utilization of waste heaps of the former mines. There are 5-6000 waste heaps of the operating and the closed mines in Hungary. 2000 of these waste heaps have already been estimated, and researches show that total amount of waste heaps can be calculated to 1 billion tones. These researches left out of consideration waste heaps exploited and placed in deep lignite mining. In several projects and researches we analysed processing of waste heap and possibilities to use its components. A processing technology for utilizing waste heaps has been developed based on laboratory and pilot plant tests. Great amount of useful materials of quarrying waste heaps can be utilized with this technology. Tests were also done for processing waste heap of a former ferrous metals mining. The developed processing technology contributes to use these waste heaps as aggregate for cement industry, as dielectric and aggregate for construction. The essay presents in details main characteristics of waste heaps, technologies already used for processing waste heaps of quarrying and ferrous metals mining, mass balances and qualitative parameters of the end products."

Jan 1, 2011

By Eugie Kabwe

The velocity of detonation (VOD) is a significant property considered when rating an explosive. It may be quantified as a confined or unconfined velocity. The confined velocity is the rate at which the detonation wave propagates through an explosive within a blast hole or any restrained space. The unconfined velocity emanates when an explosive is detonated in the open. However, the confined velocity is more significant as explosives are usually employed under a definite degree of confinement. This paper evaluates the increment of air deck volume and its effect on the VOD. The air gap (air deck) volume is increased stepwise from 10 to 30% of the total blast hole volume by reducing the stemming height in the collar zone. Thereafter, the VOD estimation in the 172-mm-diameter explosive column is conducted using the Dáutriche technique. It is observed that the VOD reduced with the increasing air deck volume and detonation failure is high when 30% of the blast hole volume is replaced with air deck. It is deduced that the increment of the air deck volume has an effect on the attenuation of the steady-state VOD.

By O. MacIntosh

The Round Mountain gold mine, located 90 km (55 miles) north of Tonopah, Nevada began large-scale production in 1977. During 2008 Round Mountain Gold Corporation (RMGC) relocated the primary crusher facility approximately 300 meters (1,000 feet) to make room for the next phase of open pit mining activities. This facility was installed in 1988 and used a log-crib retaining wall and dump pocket RMGC selected Hilfiker Retaining Walls and Collins Engineers, Inc. to provide design and materials for a new 17 meter (56 feet) high Mechanically Stabilized Embankment (MSE) wall to support the haul trucks at the new location. The construction contractor was EarthTech West Ltd. of Norwood, Colorado. An MSE wall with a cast-in-place concrete face was chosen as a durable, yet less expensive alternative to the reinforced concrete dump pocket that was originally designed for the project. The arrangement of the MSE wall is of an unusual configuration to meet a variety of operational and maintenance requirements. This paper outlines the selection process, design, and construction of the MSE wall.

Jan 1, 2009

By A. D. Kalogeropoulos, T. N. Michalakopoulos

This paper deals with the numerical simulation of rock cutting laboratory tests using the discrete element method. The main objective is to provide a method for calibrating numerical DEM models of rock cutting in a systematic way so that realistic results are yielded. The numerical models are developed with the discrete element code Yade, which models rocks as a collection of bonded spheres. The models are calibrated in a four-step process based on the design of experiments method and optimization. The calibrated models are evaluated both quantitatively and qualitatively against actual laboratory cutting tests, in terms of the ratio of the simulated mean cutting force to the actual one and the cutting force time series, respectively. The fully calibrated models showed that the simulated cutting process matched qualitatively the actual cutting force recordings and underestimated the mean cutting force by approximately 3%. It is concluded that well-calibrated numerical simulations of the rock cutting process can provide not only a better understanding of the process itself but also quantitative data regarding the cutting force and energy requirements.

Dec 28, 2022

By John Reilly

Costs of complex/underground projects have been consistently underestimated and delivery on time and on budget has been problematic. This has been attributed, to inadequate cost estimates and unidentified and/or insufficiently managed risk. Use of probabilistic cost estimates like the Washington State Department of Transportation?s CEVP® process (developed by the author and others) has produced more realistic cost estimates, explicitly identified and quantified risk (as input to risk management plans) and early awareness of key project issues. This paper updates previous work (NAT 2004), adds implementation detail for probalistic cost estimating as used by WSDOT, FHWA and other agencies and will address key issues in risk management, as related to probalistic cost estimates.

Jan 1, 2008

By J. C. Watts

Monitoring and control of conventional industrial wet grinding circuits is conceptually straightforward. However, since production objectives and operating constraints can vary widely from plant to plant, there is probably no single overall grinding circuit control strategy which is "best" in all cases; in-variably some compromise is necessary between performance desired under ideal conditions and performance achievable in practice. The recent advent of relatively low cost, reliable, high speed small computer systems is revolutionizing daily operations in increasing numbers of metallurgical processing plants. Of special power and capability is a hierarchical computer network like that currently in use at the Pinto Valley Operations of the Cities Service Company. Several satellite processors for key plant areas communicate with a master computer operating under a powerful multitasking real-time operating system. Hardware and software structure is such that downtime on one of the processors -including the master -does not have a major impact on overall system operation. Admittedly, the powerful, core efficient table driven satellite software, which handles process/computer communication, calculation of nonmeasured process variables, and basic Direct Digital Control functions, is difficult to modify. However, important high level process monitoring, report preparation, graphic display, and supervisory control functions -including economic optimization -can be implemented by project engineers at the plant site. Thus, for example, new control strategies can be quickly examined and rapidly evaluated. Such computer monitoring capability also permits use of short duration process pulse tests for approximate dynamic modeling and rapid calculation of controller tuning constants for single loop dominant systems. Following a brief back-ground discussion of the Pinto Valley Project, we present some of the more interesting results and conclusions of our work over the past year.

Jan 1, 1978

By Edward (Ted) Dowey

City Water Tunnel No. 3 is being built in order to provide a redundant system for delivering 4,542,500 m3 (1.2 billion gallons) of water per day throughout the five boroughs of New York City. The present tunnels, City Tunnel No. 1 and 2 (Figure 1), were put in service in 1917 and 1936 respectively, and both have been in continuous service. Tunnels No. 1 and 2 can-not be shut down for inspection or repair until City Tunnel No. 3 has been completed. City Tunnel No. 3 has two stages (Figure 1).Stage One is 20.1 km (12.5 mi) long and is presently delivering drinking water to the boroughs of the Bronx and Manhattan. Stage Two consists of the Brooklyn-Queens Tunnel 17.7 km (11 mi) and the Manhattan Tunnel 14 km (9 mi). The Brooklyn-Queens leg is complete and is set to be put in service soon. The Manhattan Tunnel is being constructed and is the subject of this paper. The Manhattan Tunnel (Figure 1) is comprised of three legs: the north, south and east legs. The con-tract includes the excavation of 8,976 m (29,500 ft) of tunnel and the lining of 14,561 m (47,773 ft) of tunnel. The south tunnel, 5,705 m (18,720 ft), was excavated but not lined, under a previous contract. The tunnel ranges from 181 m (600 ft) to 152 m (500 ft) in depth in the bedrock under Manhattan. The tunnel contract also includes the construction of nine new shafts, 161 m (530 ft) average depth, and the completion of a tenth shaft (the previously built construction shaft). The Manhattan Tunnel contract was awarded to the sole bidder Schiavone/Shea/Frontier Kemper Joint Venture (SSF) for $668,532,680.00, on January 31, 2005. The Manhattan Tunnel was designed ?in house? by the New York City Department of Environmental Protection (DEP) and the construction management was provided by a combined staff of the DEP and a joint venture of Jenny Engineering and URS.

Jan 1, 2008

By L. M. Anisdahl

Ventiflex is a flexible ventilation duct system with a global market within mine and tunnel ventilation. The system is distributed in a wide range of qualities and dimensions. It is very important that ventilation systems are designed correctly in mines and tunnels. An incorrectly dimensioned system might result in bad air quality and too high costs. The objective of this study has been to assess some important design parameters for ventiflex comprising the friction loss factor for the duct wall itself, as well as the shock loss factors and the leakage factors for the different couplings systems. This has been obtained by carrying out a large scale experimental program on ducts with all the three different couplings: Velcro, zip and steel-ring. Pressure profiles and air flow rates have been measured, and based on these data the different factors have been calculated. The following results have been obtained: A friction factor l = 0,012 (K = 10) for the duct wall, a shock loss factor z = 0,0125 for velcro- and zip couplings, a shock loss factor z = 0,005 for steel-ring couplings, and a leakage factor f* = 0 mm2/m2 for all three coupling types. The latter result proves that no leakage is possible for a correctly installed duct with proper alignment. The results also confirm that ventiflex complies with class S, or better, according to the SIA-norm. However, whether ventiflex should be designed as class S, A or B according to the SIA-norm, depends on the particular application.

Jan 1, 2009

By K. Oraee

Mining of copper ore and the related industries play an important role in Iran?s economy. Copper ore production in Iran accounts for 75% of the total production in the Middle East. All activities related to copper, that is, exploration, production, refinement etc are owned and managed by state owned companies. Decisions have been made to privatize all these activities. To assess the success of this privatization process, different components of the industry must be subject to economic analysis. In this paper, the cost estimation of all operations has been carried out. The total potential and attainable revenues have also been estimated using historical data available from the industry. Risk is a major factor in all mining activities and the copper industry of Iran has been subject to risk factors arising from many internal and external variables. These variables have been recognized and their effects evaluated. The effect of risk on the economic feasibility of the operations in the industry has also been analyzed.

Jan 1, 2011

By Andre Balt, Pierre Hofmeyr

It is only recently that automation has been applied to mining analytical laboratories. This paper describes the use of automation in the laboratory analytical process of hard-rock mining and geological samples and slurries in mining concentrator plant process control laboratories. Types of analysis include fire assay, XRF, ICP and wet chemistry. The benefits of automation are reduced unit cost of analyses, greatly reduced staff requirements, higher quality of data and very fast turn-around times.

Jan 1, 2005

By R. D. Peterson

As underground mine operations expand, the ventilation systems supporting them become complex. Complexity increases with periodic ventilation changes. New diagonal connections require a rebalance of resistance to maintain airflow in affected splits in the system. Incidents of mine fires and explosions have occurred in U.S. coal mines when diagonal connections resulting from ventilation changes have resulted in changing airflow directions. MSHA regulations prohibit the reversal of airflow and poor ventilation practice in general, but regulations cannot stipulate or recommend proactive preventative measures because every situation is different. This paper discusses the phenomenon of diagonal branches and recommends practical precautionary measures that can be taken to prevent airflow reversal in planned ventilation changes.

Jan 1, 2012

By M. P. Valoski

Mine fires and/or explosions continue to occur. While these are unusual events, they comprise emergency situations. Whenever one of these events occurs, the Mine Safety and Health Administration (MSHA) responds with specially trained teams, mine fire experts, sophisticated scientific instrumentation, and trained instrument operators. In order to analyze mine air samples on-site, because time is of the essence, MSHA has a Mobile Gas Laboratory. The laboratory, which is stored near Pittsburgh, is totally self-contained. Sending air samples to a laboratory would take too long. Mine fire experts need the results of the latest analyses as soon as they are finished. The mobile laboratory is housed in the box of a diesel truck. Benches line both sides of the laboratory. Gas chromatographs are mounted on the benches. There is sufficient bench space for multiple bench top gas chromatographs. These instruments and their controllers are shock and vibration isolated to protect them during transit. The mobile laboratory can operate using on board diesel generators or line power. An uninterrupted power supply (UPS) supplies power to the instruments while switching from generator to line power or visa versa. Therefore, analysis of samples can proceed without interruption if a power failure would occur. In the rear of the mobile laboratory are racks that hold compressed gas cylinders. These cylinders contain carrier gas and compressed air. An air compressor is housed under the laboratory to operate the gas chromatograph actuators. Within several hours after arriving at a mine the instruments have stabilized and have been calibrated. The mobile laboratory is ready to begin analyzing air samples. The mobile laboratory has proved itself at many mine fires and explosions since its purchase.

Jan 1, 2009