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By Peter Kreisman

This paper and four other papers on the MEQB Regional Copper-Nickel Study, presented today at the 1980 SME-AIME Fall Meeting are based on four years of extensive inter-disciplinary research and impact analysis supported largely by the Legislative Commission on Minnesota Resources. This study produced over 180 technical reports, the results of which are summarized in an Executive Summary available from the Minnesota State Planning Agency, St. Paul, Minnesota. Those wishing to examine the many scientific, engineering, environmental, social or economic issues addressed by the study are encouraged to obtain a copy of the executive summary. The executive summary includes a bibliography of all technical reports produced by the Regional Copper-Nickel Study and describes the five-volume, 26 chapter Regional Copper-Nickel Study Report.

Jan 1, 1980

By Yoginder P.

ACKNOWLEDGEMENTS Authors sincerely appreciate the interest, cooperation and technical support of the coal company management and staff in conducting the study. Without their assistance this study would not have been possible. INTRODUCTION AND SPECIFIC OBJECTIVES An area in the midwest overlying abandoned room-and-pillar mine workings at, shallow depth has been experiencing subsidence movements with associated damage to surface structures. Other coal companies in the area have also been having similar experience. A 16 - month cooperative study between a mining company and the Department of Mining Engineering at SIUC was developed with the following objectives. 1) Determine the extent to which surface and subsurface movements were complete in the area, 2) Identify the mechanism(s) of subsidence in the area, 3) Determine the influence of geology and hydrology of the area on subsidence movements, 4) Observe the conditions of abandoned underground workings with a borehole TV camera, 5) Characterize the extent of damage and monitor possible progressive damage to selected surface structures, and 6) Make recommendations to a) minimize further damage to surface structures in the area, b) identify future areas that may be affected by these movements and c) modify mining systems to minimize these movements.

Jan 1, 1986

This paper presents a virtual prototype for the stress analysis of cable shovel components based on combination of flexible and rigid body approach. The general mechanical system of the cable shovel is modeled as a multi-body system with rigid and flexible bodies. The relevant theories applied for the dynamic model are described in terms of Lagrangian multi-body dynamics and finite element method. A virtual prototype of the cable shovel is built in the Automatic Dynamic Analysis Mechanical System (ADAMS) environment, which allows visualizing the motion of general mechanical system and analyzing the dynamic stress of structural components of the cable shovel. An example is given to perform dynamic stress of durability analysis for the boom and handle. Attention of this study is devoted to the mechanisms of damage of the cable shovel and also the critical high stress areas. Keywords: Cable shovel, Von Mises stress, Virtual prototype simulation, Stress virtualization.

Jan 1, 2009

By S. Suwansawat, D. J. Maconochie, C. C. Chang

This paper describes the overall delivery of the tunneling for the Mass Rapid Transit Authority of Thailand’s Chaloem Ratchamongkhon Line in Bangkok and the constraints provided by the alignment. Eight earth pressure balance tunnel boring machines were employed under two major civil works contracts to drive approximately33 kilometers of tunnel in soft saturated ground beneath the crowded streets of Bangkok. Responsibility within the contract for building damage provided an inherent control for ground movement arising form tunneling when the right of way was narrower than the influence zone. These limits affect the earth pressure balance requirements and permissible ground loss. The methods adopted to limit ground movements and deal with the various obstacles to tunneling influenced the design and operation of the machines. The challenges provided by the need to tunnel through numerous lines of piled foundations of canal bridges and overpasses crossing the alignment are described.

Jan 1, 2001

By Yifan Ding, Shemek Oginski, Patrick Finn

The Manhattan section of the New York Water Tunnel No. 3 constructed by the Schiavone/Shea/Frontier-Kemper Joint Venture is a $668 million project. The contract includes a tunnel drive of 8.85 km (29,045 feet), tunnel lining of 14.77 km (48,468 feet)and construction of nine shafts ranging in depth from 143 m (469 feet) to 169 m(555 feet). Construction methods for excavation of the shafts are presented including raise bore, ground freezing, soil excavation, blasting, slashing, muck handling, rock support and shaft final concrete lining.

Jan 1, 2007

Syncrude Canada produces a large part of Canada’s crude oil supply. The company processes about 225,000 bbl/day. The oil produced is used for jet and automobile fuel, home heating oil, plastics and other consumer synthetics. Crude oil is produced through a process of mining, extracting and upgrading bitumen. A rich supply of bitumen is contained in the Athabasca oil sands deposit in northern Alberta. Tailings from the bitumen processing are sent to a settling basin.

Jan 1, 2000

By G. A. Irdi

An automated method of microscopy for determining the pyrite size distribution on two base coals that were crushed to 28 mesh x 0 has been developed. Polished epoxy-bound coal pellets were prepared and examined by a Zeiss IBAS image analyzer utilizing a program developed from provided software. Pyrite size distribution determination is considered a necessary first step in pyrite characterization that could lead to successful predictions, by microscopy, of a coal's theoretical pyritic sulfur removal. Our research efforts to date have indicated that the IBP-S can be a reliable instrument for determining pyrite size distribution in crushed coal. A program was also developed to convert pyrite size data to a weight basis for comparisons to the results from chemical analyses. The problems encountered in our research and their solutions will be presented in the discussion.

Jan 1, 1986

By Mahaboob Basha Shaik, Shakuntala Tudu, Indrajit Paul, Chandra Sekhar, Neha Gupta, Amit Kumar, Srinivas Dwarapudi, Arvind Kumar Patel

In this study, the effect of colemanite and calcined colemanite (CC) addition on the properties of iron ore pellets is studied. The pellets are prepared in a lab without and with 0.2% colemanite and varying amounts of CC from 0 to 1.0 wt%in steps of 0.2%. A reference pellet is prepared under typical plant conditions, and the properties of the reference pellet are considered as the base value for improving the cold compressive strength (CCS) while maintaining the other parameters at an acceptable limit without altering the pellet. The study also aims to provide a detailed characterization of colemanite and calcined colemanite to better understand their behaviour during firing. The lab-scale results show that the CCS of pellets made with 0.2% colemanite was reduced by 222 points (60%) as compared to the reference pellets due to crack formation during firing. The results show an improvement in the CCS of the indurated pellets with CC dosage up to 0.4%, and decreasing strength is noted thereafter. It is observed that the swelling index increases with the increase in calcined colemanite dosage. To simulate plant conditions, reference pellets and pellets with optimized CC dosage were fired in a plant furnace.

Oct 16, 2020

By R. L. Virta

Common clay is a natural, fine-grained material composed of hydrous aluminum silicates. Shale is a laminated sedimentary rock that is formed by the consolidation of clay, mud or silt. Production About 150 companies produced common clay and shale in 41 states. In states not reporting production, common clay and shale probably was mined and sold for construction applications by companies not participating in the U.S. Geological Survey (USGS) canvass of producers. Domestic production in 2005 was estimated to be 24.8 Mt (27.3 million st) valued at $176 million. This was based on a preliminary survey of the common clay and shale industry. The leading producer states, in decreasing order by tonnage, were North Carolina, Texas, Alabama, Georgia and Ohio.

Jan 1, 2006

By S. Mohanta, S. Chakraborty, B. C. Meikap

"An air dense medium fluidized bed separator is an efficient dry process for the removal of undesirable gangue material from run-of-mine coal. Its cleaning performance depends on a variety of operating parameters that are interrelated in unknown, complex ways. A literature review showed that these parameters' effects had been experimentally investigated using a traditional one-variable-at-a-time approach, which is highly inefficient and sometimes misleading because many of the parameters often interact with each other to alter the overall equipment performance. Also, it is realized that the interrelationship among these parameters can have a significant effect on equipment performance. Therefore, to correctly evaluate the effects of individual parameters as well as their interactional effects on the separation performance of an air dense medium fluidized bed, we conducted a scientific study based on response surface methodology. Empirical models for two key response variables, namely, product ash and combustible recovery, were developed and subsequently used for identifying an appropriate operating region to achieve optimum separation performance. Furthermore, the optimum performances predicted from the empirical models were validated against experimental data. Preliminary results show a strong interaction among the operating parameters investigated in this test program.IntroductionFluidization is widely applied in industry for its various useful features. In the coal industry, it is used in the air dense medium fluidized bed (ADMFB) separator for the beneficiation of run-of-mine coal. In this separator, a medium is created by suspending fine magnetite particles in an upward air flow, and this pseudo-fluid is used as the beneficiation medium, with the lighter coal particles floating to the medium’s surface while heavier particles sink to the bottom. This separation technique had been receiving a significant amount of attention worldwide in recent times for its specific advantages of low operating cost and less restriction for small capacities (Luo and Chen, 2001; Sahu et al., 2009; Dwari and Hanumantha Rao, 2007; Van Houwelingen and de Jong, 2004), but it is still not a well-established industrial practice because of the availability of efficient wet processing technology. However, with a revival of interest in the dry beneficiation of coal, in general, and ADMFB, in particular, there is once again a concerted effort to improve the efficiency of the ADMFB process, and successive improvements have been made to make this process a competitive and viable option. The existing literature reveals that most of these research efforts had been essentially focused on the identification of a single parameter that has a key influence on separation performance, without taking notice of parameter interactional effect. For example, Luo et al. (2004) proposed a pressure drop number to distinguish separation performance without considering the bed height and gas velocity, which are intimately related to this proposed pressure drop number."

Jan 1, 2015

By John E. Appleby

Grupo Acera, HYLSA originated in 1942 when Hojalata y Lamina began operations to supply steel strip for the Cuauhtémoc Brewery, the parent company. Production began in April, 1943 with growth accelerated because of World War II. By 1948 the company was producing its own steel from electric furnaces charged with scrap iron. Further expansion was hampered by the fluctuations in availability, price and quality of scrap iron. As a result, a search was made for a suitable process to enable HYLSA to satisfy its need for a reliable source of feed for its steel-making facilities. Their relatively low iron requirements at the time did not justify the very high capital investments required using the conventional blast furnace method. Processes which by-passed the blast furnaces were very much in their infancy and were not commercially tested. HYLSA then undertook an investigation of the direct reduction processes, knowing full well that much larger companies in other countries had investigated several processes but their work had not established a trend toward direct reduction or any particular process. However, after much effort and persistence HYLSA arrived at a process which suited their conditions. By using Mexican iron ore and natural gas they developed the now well-known H. y L. Process to produce sponge iron. Concurrent with the start of investigations which led to the H. y L. Process, HYLSA began an exploration program for a suitable source of iron ore. Thus in 1951, Cia. Minera Las Encinas, S.A. was formed, culminating in the development of the ore bodies near Pihuamo in the State of Jalisco. Mining commenced and ore was

Jan 1, 1971

By Mustapha A. Raji, Alafara A. Baba, Christianah O. Adeyemi, Aishat Y. Abdulkareem, Rafiu B. Bale, Malay K. Ghosh

The increasing demand for pure aluminum and aluminum compounds of industrial quality from kaolinite ore cannot be overemphasized. Nigeria is one of the African countries endowed with abundant solid mineral resources that have not been sufficiently exploited to assist its indigenous industries. A wide array of applications of pure aluminum and its compounds are available, such as paper filling, refractories, adsorbent, catalysis, and paint additives. In this study, the upgrading of a Nigerian biotite-rich kaolinite ore by a hydrometallurgical route was investigated in oxalic acid media. During leaching studies, the effects of parameters including reaction temperature, lixiviant concentration and particle size on the extent of ore dissolution were examined. At optimal conditions (1.0 mol/L C2H2O4, 75 °C), 92.0% of the initial 10 g/L ore was reacted within 120 min. The dissolution curves from the shrinking core model were analyzed and found to conform to the assumption of surface diffusion reaction, and the calculated activation energy of 33.2 kJ/mol supported the proposed model. The unreacted product (~8.0%) analyzed by XRD was found to contain siliceous impurities and could serve as a valuable by-product for certain industries.

By Mustapha A. Raji, Alafara A. Baba, Christianah O. Adeyemi, Aishat Y. Abdulkareem, Rafiu B. Bale, Malay K. Ghosh

The increasing demand for pure aluminum and aluminum compounds of industrial quality from kaolinite ore cannot be overemphasized. Nigeria is one of the African countries endowed with abundant solid mineral resources that have not been sufficiently exploited to assist its indigenous industries. A wide array of applications of pure aluminum and its compounds are available, such as paper filling, refractories, adsorbent, catalysis, and paint additives. In this study, the upgrading of a Nigerian biotite-rich kaolinite ore by a hydrometallurgical route was investigated in oxalic acid media. During leaching studies, the effects of parameters including reaction temperature, lixiviant concentration and particle size on the extent of ore dissolution were examined. At optimal conditions (1.0 mol/L C2H2O4, 75 °C), 92.0% of the initial 10 g/L ore was reacted within 120 min. The dissolution curves from the shrinking core model were analyzed and found to conform to the assumption of surface diffusion reaction, and the calculated activation energy of 33.2 kJ/mol supported the proposed model. The unreacted product (~8.0%) analyzed by XRD was found to contain siliceous impurities and could serve as a valuable by-product for certain industries.

By G. W. McMahon

Following the Sago Mine accident, the U.S. Mine Safety and Health Administration (MSHA) asked the U.S. Army Engineer Research and Development Center to study several possible methane explosion scenarios in the Sago coal mine. The study used a 0.3-m (1-ft) resolution map of the mine to produce a 3-dimensional (3 D) model of a portion of the mine, including the sealed area where the explosion occurred. An advanced 3 D computational fluid dynamics (CFD) code was used to calculate the explosion pressures within the sealed area, on the mine seals and in nearby regions of the mine. Based on the best available information on methane concentrations and assumptions on homogeneity and on layering and mix composition, three separate initial conditions of methane-air concentrations and location were studied. This paper discusses the CFD modeling technique, the results of the calculations, the challenges of conducting this type of modeling and the advantages and limitations of CFD modeling of accident investigations of mine explosions.

Jul 1, 2010

By John M. Arnold

Several years ago it became apparent to some of our people that; there was developing a very definite need for largee coal reserves in the West to satisfy- the need for fuel for the furnaces of electric generating plants with the rapid development of, the West, of both population and industry, it was impossible for hydro-electrics plants to keep up with the ever increasing demand for electricity. In 1960, Mr. E. R. Phelps, then associated with the engineering department of Peabody Coal Company, began a search for and development of coal deposits in the very remote northeast section of Arizona near the village of Kayenta. Travel to this section of the country was not easy even at this late date, and it was an eight hour drive from Farmington, New Mexico to Kayenta, Arizona, a distance of some 130 miles. The trip was over roads that even' a-horse and wagon had trouble negotiating and a four wheel drive vehicle was about the only type of transportation that could satisfactorily traverse these roads, as testify many badly beaten sedans and coupes that tried it. Since that time a very excellent road has been constructed from Shiprock; New Mexico to Cameron, Arizona where it junctions with another excellent road that runs north to Page, Arizona and the Lake. Powell area and south to Flagstaff, Arizona on highway 66. Kayenta is a small village nestled at the foot of the Black Mesa near its northeast extremities. The coal deposits of interest were on the surface of the mesa. This location presented another problem, as the only trail to the top of the mesa was intended for walking, horseback, or a brave soul In a horse and wagon. Once again the four wheel drive vehicle was about the only answer. To reach the coal deposits you must climb the mesa, which is vertical ascent of some 1,500 feet, and then proceed southward into the bowl of the mesa with an ensuing descent of some 1,000 feet, finally coming to an elevation of 6,500 feet, at which elevation the coal outcrops become apparent.

Jan 1, 1969

Exploration of new resources and development of new equipment and designs are an ever changing facet of mining. New equipment to handle specialized operations is being developed and new techniques for its use explored. One such system is reviewed. Another is a potential system for handling the thinner stray coal seams between the more profitable thick seams. The availability of federal coal leases in the West is reviewed and current planning discussed. Gulf Coast lignites have been of much interest in recent months and are overviewed.

Jan 1, 1979

By W. Missildine, J. K. Hrica, I. Benbourenane, T. J. Orr, J. L. Bellanca

Each year, haul truck accidents account for a large portion of mining injuries and fatalities. To better understand why these accidents continue to occur, researchers from the National Institute for Occupational Safety and Health (NIOSH) utilized a cognitive task analysis methodology to identify the user requirements of surface haul truck operators and assess differences in perceptions between operators, managers, health and safety professionals, trainers, and maintenance personnel. Additionally, researchers used the critical decision method to focus on better understanding the cognitive demands, decision-making, and problem solving during nonroutine incidents. The preliminary results of this study identify and explore themes within the broad categories of hazards, skills & expertise, and training and provide detailed accounts of nonroutine incidents such as near-misses, loss of control, and collisions. These accounts reveal insights into operator decision making and event progressions that can then be used to build more realistic training scenarios and address hidden hazards and root causes of these incidents. These results, along with potential solutions offered by study participants, can inform future research and help identify creative interventions that can be used by mine operators to address haul truck safety issues

Mar 2, 2022

By Sean Masse

New Gold?s New Afton Mine, located 8 km (5 miles) west of Kamloops, British Columbia, is a 4.5-Mt/a (5-million stpy) block cave mine, making it the highest tonnage underground hard rock mine in Canada. The reserve is estimated at 52.5 Mt (55.9 million st) with grades of 0.65 g/t (0.02 oz/st) gold and 0.93 percent copper (2012). Commercial production was achieved in July 2012 and nameplate production was achieved ahead of schedule in September 2012, with the cave breaching to surface in 2013. The mill has a SAG and a ball mill with a froth flotation circuit.

Jan 1, 2014

By W. R. Dengler, R. S. Brown

In 1974, Brunswick Mining and Smelting Corporation Limited started a 48 million dollar expansion programme at their property in Bathurst, New Brunswick. A portion of the expansion plans includes a 26 foot diameter 4,525 foot deep shaft, underground crusher and conveyor excavations and lower level access development. J. S. Redpath Limited was awarded the contract for the new shaft and associated rock work in May 1974. Brunswick Mining and Smelting Corporation Limited, a member of the Noranda Group, operate this 10,000 ton per day lead, zinc, copper plant with proven reserves in excess of 90 million tons. While most of the ore is provided by the underground operation at the Number 12 ore body, some tonnage is produced from the open pit at the Number 6 ore body. Long range plans indicate a phasing out of the open pit and an increase in production from the underground operation. Existing facilities at the underground mine could not provide additional tonnage, thus the requirement for a new shaft. (Figure 1) The new shaft will also provide access to ore below the 2,800 level which is currently the bottom level of the existing facility. The contract called for sinking a 26 foot inside diameter, nine compartment concrete shaft 4,525 feet deep (Figure 2). Station access and ramp development from existing workings would be required to the bottom of the new shaft. In addition, development work for new crushing and conveying facilities was needed simultaneous with the shaft sinking.

Jan 1, 1976

By R. E. Mitchell

Environmental Impact Assessment (EIA) is the accepted method for evaluating proposed mining and other industrial projects to obtain regulatory approval and to help companies plan for responsible development. Another evaluation system becoming increasingly more common for proposed projects is the Environmental, Social and Health Impact Assessment (ESHIA). An ESHIA differs from an EIA for its more comprehensive and inclusive approach to evaluate potential impacts on public health, and its ecosystem services approach to assessing biodiversity impacts. An ESHIA may also be required by certain lenders for financing major projects. Conducting an ESHIA for a proposed mining development is not without its challenges, with costs, scheduling, regulatory concordance and other constraints to be considered. This paper examines some benefits and challenges of ESHIAs and summarizes lessons learned using a case study approach.

Jan 1, 2012