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In late 1993, Inco Ltd. completed a $600-million environmental improvement project at its Sudbury, Ontario operations -the largest single environmental project ever undertaken by a Canadian corporation. Efficient new facilities and innovative technologies installed during the course of the project have also significantly improved Inco's productivity and competitiveness. In early May 1994, a panel of 18 Inco authors contributed to a Technical Forum, "Environmental Programs at Sudbury," presented at the 96th Annual General Meeting of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM) in Toronto. Their papers have been published in CIM's Toronto `94 Proceedings Volume, pp. 62-77. The following report draws primarily on discussions of Inco's milling and smelting operations published in the Proceedings Volume. The Proceedings Volume also includes papers on the acid and oxygen plants and on engineering, construction and commissioning of the project. The 222-page Proceedings Volume is available from CIM, $C27 plus shipping. To order, contact: V. Ward, CIM, Xerox Tower, 1210-3400 de Maisonneuve Blvd W, Montreal, Quebec, Canada H3Z 3B8; phone 514-939-2710, fax 514-939-2714. Lane White, Publisher.

Jan 1, 1994

Liebherr Mining Equipment Co., of Newport News, VA and Baxter Springs, KS, introduced the T282, a new two-axle, diesel-electric, AC drive haul truck with a payload capacity of 327-t (360-st). The T282 was unveiled at a press briefing in October 1998 at the company's Baxter Springs research and development1 manufacturing facility. In addition to an increase in pay- load capacity, the truck's AC drive system has been de- signed to allow for easy configuration to a trolley-assist system with minimal additional equipment. The T282 provides fuel savings, reduced maintenance requirements, and reduced downtime and maintenance costs, providing the mine operator with increases in productivity. Basic dimensions and weight of the T282 are: ? Overall length, 14.5 m (47.5 ft). ? Overall width, 8.7 m (28.7 ft). ? Loading height, 6.5 m (21.2 ft). ? Height - body up, 13.9 m (45.9 ft). ? Empty vehicle weight, 201 t (221 st). ? Operating weight - loaded, 528.6 t (582.6 st). ?Engine, Detroit Diesel 16V4000 at 2 MW (2,750 hp). ?Electric drive system, Siemens/Liebherr.

Jan 1, 1999

By S. K. Kawatra, T. C. Eisele

Microorganisms, such as the bacteria Thiobacillus ferrooxidans, have been reported to depress pyrite flotation (Elzeky and Attia, 1987; Atkins, 1990). However, the depen¬dence of the depression on the type of organism or on suspension pH is still being determined. In this study, the relative effectiveness of various microorganisms (chemolithotrophic bacteria, chemoorganotrophic bacteria and yeast) over the pH range of 2 to 12 was studied. Screen¬ing tests using microflotation showed that every microorgan¬ism tested was capable of depressing naturally hydrophobic pyrite at acidic pH. Larger-scale experiments with both mineral pyrite and coal pyrite using Thiobacillus ferrooxidans and Saccharomyces cerevisiae as depressants, showed that these microorganisms are very effective depressants for mineral pyrite at acid pH, but they are largely ineffective at neutral and alkaline pH, where the mineral pyrite surface is not naturally hydrophobic. The flotation response of the coal pyrite was completely different from the mineral pyrite. The coal pyrite was most floatable near neutral pH, with the floatability decreasing in acidic or alkaline solutions. De¬pression of the coal pyrite by yeast was not selective between the pyrite and the associated coal under the experimental conditions.

Jan 1, 2000

By Juan Eduardo Barrera

SUNNARY AND CONCLUSIONS Argentina presents to the foreign and local investors a mineral wealth that is largely unexplored, untested, underdeveloped and therefore incompletely evaluated. In view of the above, the new administration of President Raul Alfonsin through its Department of nines has designed and implemented a strategy ( Plan de Expansión Ninera P.E.M.), whose main objective aims at improving the "investment climate" in the sector. It is the Government's basic intention to apply the Mining Promotion Law with responsibility but with generosity to encourage the attraction of investment (local and foreign) to the sector. The establishment of a Data Bank system to evaluate possible new potential ore mining developments will help to connect the owners of potential projects with investors outside the sector. Argentina has an interesting gold ore potential. Estimated reserves of individual projects already known amount to almost 300 tonnes of gold for potential production. The government strongly believes and present information indicates that more systematic exploration has to be undertaken in the Jurassic areas that almost cover the whole of Patagonia. Two recent gold discoveries (Angela in the Chubut province, and Cerro Vanguardia in Santa Cruz province) indicate the potential of this area.

Jan 1, 1988

By Angelina Anani, Nilufer K. B. Akbulut, Sefiu O. Adewuyi

Crucial information about safety, design, and operation can be utilized in underground mines from ground movement data. Communicating the information and exploring new findings can be a challenge in a decade where there is an ever-increasing volume and velocity of data due to advancements in mining technologies. This challenge escalates for geotechnical data as it is multidimensional, depending on the space and the rate it takes place. To tackle this challenge, geotechnical engineers should focus on utilizing simple yet compelling visualization of rock mass data in 3D. Competent visualizations of ground conditions as a Trigger Action and Response Plan (TARP) could ease the communication of safety concerns and the exploration of rock mass displacement and strain surrounding an opening at an underground mine. Therefore, this study focuses on using scientific visualization methods by rendering geotechnical data over the surface of a 3D mesh model to display TARP levels. The study is conducted at the San Xavier (SX) Underground Mine Laboratory’s East decline. The project aims to produce visualizations that optimize the use of geotechnical data in near-real-time.

Feb 1, 2025

By T. E. Bernard

"Refuge alternatives provide shelter to miners trapped underground during a disaster. Manufacturers must demonstrate that their refuge alternatives meet the U.S. Mine Safety and Health Administration (MSHA) requirements for oxygen supply, carbon dioxide removal, and management of heat from the occupants and mechanical/chemical systems. In this study, miner size and activity level were used to determine the metabolic heat rate, oxygen requirements and carbon dioxide generation that are representative of miners in a refuge situation. A convenience sample of 198 male miners was used for the distribution of current U.S. coal miners, and the composite 95th percentile height and weight were determined to be 193 cm (76 in.) and 133 kg (293 lb). The resting metabolic rate (RMR) was determined to be representative of activity level in a refuge alternative. The highest likely metabolic heat generation ranged from 113 to 134 W, depending on occupancy. The highest required oxygen supply and carbon dioxide removal were estimated to be 23 L (0.81 cu ft) of oxygen per hour per person and 20 L (0.71 cu ft) of carbon dioxide per hour per person, which means the margin of safety is 50 percent or more compared with the MSHA requirements. The information on metabolic heat generation can be used to assess refuge alternative thermal environments by testing or simulation. The required oxygen supply and carbon dioxide removal can be used to assess refuge alternative requirements. IntroductionRefuge alternatives provide shelter to miners trapped underground during a disaster. Manufacturers must demonstrate that their refuge alternatives meet U.S. Mine Safety and Health Administration (MSHA) requirements for the supply of oxygen (O2), removal of carbon dioxide (CO2) and management of heat resulting from the refuge alternatives’ occupants and mechanical/ chemical systems (MSHA, 2008)."

Jan 8, 2018

By VIVEK KUMAR HIMANSHU, PK SINGH, AK MISHRA, MP ROY, RAVI SHANKAR

Underground blasting has many challenges. The primary aim of blast designers is to optimize drilling and blasting parameters to deal with the associated challenges. Optimizing these parameters is currently based on various rules of thumb, which have many site-specific limitations. Accordingly, computation of these parameters using empirical rock fragmentation predictors can be useful for blast designers. This paper presents the results of work on burden-spacing determination by back-calculation from the empirical Kuz-Ram model for underground stope ring blasting.

By G. M. Bernard

Cerro Colorado lies on the eastern edge of the Atacama Desert in the foothills of the Andean Cordillera of northern Chile. Compañía Minera Cerro Colorado SA (CMCC) operates Cerro Colorado. CMCC, headquartered in Santiago, Chile, is wholly owned by Rio Algom Ltd., of Toronto, Ontario. Cerro Colorado is located 120 km (75 miles)east of the port city of Iquique. Access is by 30 km (19 miles) of paved highway and 70 km (43 miles) of upgraded road. The mine site is located at an altitude of 2600 m (8531 ft) on a gentle west-sloping plateau adjacent to a deep canyon (Quebrada de Parca) to the north. Temperatures are moderate, ranging from 5° to 30° C (41° to 86° F) with an average annual rainfall of 20 mm (0.8 in.). The plateau is generally covered with 20 to 30 m (65 to 100 ft) of Quatemary sand and gravel overlaying bedrock. In the immediate vicinity of the Cerro Colorado deposit, a semicircular embayment has been eroded into a steep canyon wall that cuts through the surface gravels to expose a considerable section of the underlying bedrock.

Jan 1, 1995

By John D. Shaw

1. Introduction 2. The Hydraulic Mine _ (i ) Development (i i ) Extraction ( i i i ) Transport 3. The Water Circuit 4. Manpower and Results 5. Modifications 6. Conclusions 1. Introduction The Kaiser Resources Ltd. hydraulic coal mine is located in south eastern British Columbia, Canada, at the western end of the Crowsnest Pass, next to the Town of Sparwood. The seam presently being mined is the number 10, known locally as the Balmer seam, which is a high quality coking coal, 50 feet in thickness and of an average inclination of 35 degrees. The mine was designed in the late sixties as a small scale trial unit, and was to use a single monitor unit, working 3 shifts per day on a 5 day per week basis. Experience has proved the method to be so successful as to warrant the expansion of the ancilliary facilities to cater for the increased production. The annual raw coal production from this single monitor unit has risen from 108,988 short tons in 1970 to 942,334 short tons in 1975, with a total mine labour force of about 160 men including the surface de-watering plant, mine supervision and mine administration.

Jan 1, 1977

By Kathleen Lagnese, Srikanth Muddasani, Kashi Banerjee, Carla Robinson

"Mine water generated from underground coal mining operations contains both dissolved and particulate solids. Dissolved solids primarily consist of sodium, calcium, magnesium, potassium, chlorides and sulfates. When discharged to a receiving stream without treatment, these constituents create a potentially toxic environment for aquatic life.A case study is presented to discuss how a centralized treatment plant treats mine water from six locations to meet discharge limitations for chlorides. Located in West Virginia, this facility consistently achieves less than the National Pollutant Discharge Elemenation System (NPDES) permit limitation of 218 mg/L chlorides in the discharge while generating almost zero liquid waste. The dissolved solids concentration in the influent ranges between 5,000 and 10,000 mg/L, with chloride concentrations of 1,000 to 2,000 mg/L and sulfate concentrations of 2,000 to 6,000 mg/L.The mine water is treated using advanced treatment technology to produce clean water for discharge or reuse. The treatment process comprises aeration, softening, filtration, reverse osmosis (RO) reject softening, evaporation, crystallization, final effluent remineralization and sludge dewatering. The solid waste generated in the treatment process is landfilled on site. The leachate is sent back to the facility’s thermal treatment process. Because no liquid waste leaves the property, this plant is termed a zero liquid waste (ZLW) facility.The advanced water treatment system was built to meet a new 218 mg/L regulatory limitation imposed by the West Virginia Department of Environmental Protection for chlorides discharged to surface waters. The system is designed to treat a maximum flow of approximately 795 m3/h (5 million gpd) of mine water. The treatment process utilizes RO membrane treatment to achieve the effluent criteria, and evaporation and crystallization technology to manage the RO concentrate from the water treatment process. As a result, the system produces clean water for discharge while generating zero liquid waste. The effluent water can be used for industrial purposes or discharged to a receiving stream. A water impact index (WIIx) study indicated that discharge of this high-quality water into the Monongahela River watershed may improve the water quality for downstream water users. The waste produced in the treatment process, including softening sludge and salt, is disposed of in an onsite landfill. Currently, the plant is treating at an average flow of 490 m3/h (3.1 million gpd) of mine water with an average influent chloride concentration of 1,530 mg/L and an average effluent chloride concentration of 11 mg/L."

Jan 1, 2014

By Erik Sundström, Magnus Nygren

The study explores the influence and consequences of safety initiatives on the development of safety cultures in the Swedish mining industry. It involves interviews with experts from four mining organizations, highlighting themes such as organizational structures, safety leadership, feedback, and communication.

Nov 1, 2023

By Johann Engelbrecht, Stéfan de Bruyn, Petrus van den Heever

A system for the on-stream X-ray diffractometric determination of mineral phases in slurries was developed in response to the mining industry's need for process control during the beneficiation of industrial minerals. The instrumentation for and results from testwork conducted at a phosphate rock beneficiation plant in Florida are discussed. Results show that the concentrations of the minerals apatite (var. francolite) and quartz can be accurately determined every few minutes, so that adjustments to the flotation circuit can be timeously executed from the control room. The on-stream measurements can ultimately be integrated into an automated plant control strategy. Estimates of savings on reagent and staffing costs, as well as the benefits from consistent grades and greater recoveries, have shown that the investment in such a system could often be recovered in less than a year.

Jan 1, 1999

By David C. McLean, Peter Penner, Martin de G. Salter

The Rogers Pass Project for C.P. Rail includes a 14.7 km tunnel and an 8.5m diameter concrete lined ventilation shaft to a depth of about 335m. The shaft collar is in bouldered water bearing glacial till to a depth of about 95m. Initial excavation in the overburden was with the aid of dewatering wells. When ground support problems arose the excavation was completed by a two stage freeze programme. Freeze holes were drilled from the shaft bottom. This most unusual method was successful in overcoming the difficulties safely and efficiently. The remainder of the shaft was sunk and lined conventionally. Finally, a central dividing wall was poured by jump forming from the bottom up. The wall was completed to a high standard at up to about 20 vertical metres per day.

Jan 1, 1989

By J. A. Marts, R. C. Gilmore, Jr. Bogin, S. A. Saki, J. F. Brune, J. W. Grubb

"Most, if not all longwall gobs contain explosive gas zones (EGZs), i.e., zones of explosive methane-air mixtures that can cause – and have caused – mine fires and explosions. If the coal is prone to spontaneous combustion, oxygen penetration into the gob must be avoided. This paper summarizes the significant research findings from five years of computational fluid dynamics (CFD) modeling research conducted at the Colorado School of Mines (CSM) under funding from the National Institute for Occupational Safety and Health (NIOSH). CSM Researchers have developed CFD modeling techniques to identify where and under what circumstances EGZs can form in longwall gobs and how EGZ formation and oxygen penetration depend on the ventilation method, face and bleeder ventilation parameters, injection of inert gases and the operation of gob ventilation boreholes. Recognizing these explosion and fire hazards is an important first step in improving the safety of longwall coal mines. CSM modeling research has shown that EGZ formation can be effectively controlled by adjusting ventilation parameters, choosing the proper ventilation pattern and injecting inert gases where necessary. INTRODUCTION In a project sponsored by the NIOSH Office of Mine Safety and Health Research, researchers at the Colorado School of Mines have examined gas compositions and flows in longwall gobs in order to assess explosion and fire hazards. Since gob areas are inaccessible, researchers developed a series of computational fluid dynamics (CFD) numerical modeling tools to characterize these hazards. A variety of CFD models were developed to cover progressively sealed as well as bleeder ventilated gobs for both coal and trona mines. The explosion and fire hazards posed by EGZs in longwall gobs can be summarized as follows.• If the EGZ lies closely behind the longwall face, flames and pressures from an explosion can penetrate the shield supports and reach the active face area, creating blast trauma, burn hazards and toxic, unbreathable atmospheres. • EGZs can be pushed around inside the gob by roof collapses and cave-ins. If they get pushed out into the face area, sudden methane inundations and explosion hazards in face areas can result. • Fresh air flowing into the gob can create an explosion hazard as the gas composition in the gob moves from fuel-rich inert to explosive, creating EGZs. • Ignition sources inside the gob can be frictional ignitions or spontaneous combustion. • Bleeder ventilated gobs are surrounded on all sides by an EGZ that forms along the fringe areas between the fresh-air ventilated bleeder entries and the methane-rich interior of the gob. It is suspected that diffusion flames can propagate rapidly along these EGZ fringes if an ignition occurs"

Jan 1, 2015

By VASU GANGRADE

Large-opening underground stone mines pose significant ground control challenges, including the risk of massive pillar collapses. These collapses can result in dangerous air blasts characterized by tremendous force and high velocity. Estimating the velocity of these air blasts proves challenging due to the absence of accurate air velocity instruments near the mine portals. To address this issue, this paper proposes a novel approach that leverages closed-circuit television camera footage from the mine. Specifically, it employs the optical flow algorithm implemented in Python to estimate the velocity of the air blasts, providing a valuable tool for assessing and mitigating risks in such mining environments.

Feb 1, 2024

By Oluwafemi Salami

Conducting full-scale fire experiments in underground mines is difficult and expensive. Sometimes, it is impossible to carry out fire tests in mines due to the danger they pose to mine workers and the underground facilities. However, understanding the potential occurrence of fires in a mine and their dynamics is critical to developing an appropriate emergency evacuation plan, fire suppression, and firefighting techniques. In this study, a numerical fire model using computational fluid dynamics (CFD) with fire dynamics simulator (FDS) 6.7.6 was developed to examine the influence of tunnel bifurcation on maximum temperature beneath a tunnel ceiling. The model was validated using full-scale experimental data. The maximum ceiling gas temperature predicted using FDS and measured maximum smoke temperature during the experiment shows good agreement. The study shows that bifurcation could lower the maximum ceiling temperature of fire-induced smoke in a subsurface environment. The findings from this study apply to the broader field of ventilation and fire life safety in tunnels and other underground environments.

Jun 23, 2024

By V. O. Tenorio, D. Tolmachoff, K. Willa Brown, K. J. Kingsbury, J. B. Nickels, G. J. Nail

A major design feature to consider from the initial pioneering works until reaching full mine production of icy regolith at the South Pole of Moon will be the ramp. This will allow the access of equipment and personnel in and out of the excavation area. Although most of the requirements considered when designing a ramp on the Earth are similar, the fact of working in low gravity, with zero atmosphere, the potential exposure to high radiation, extreme temperature levels and drastic changes of illumination, from intense light to total darkness, are new factors to be included. Transversal sections are obtained according to the progression sequence of the production levels, with changes in length, gradient, friction factor of the terrain and curvature when required by the location characteristics and the specification of the equipment utilized. A MATLAB script was developed to calculate all the variables, in order to obtain 3D generated surfaces from the range of possible profiles.

Mar 2, 2022

By Isabel F. Barton, Matthew J. Gabriel, CARSON ROBERTS, JOHN LYONS-BARAL, LEON DUPLESSIS, Mark D. Barton

Geometallurgical characterization is increasingly used in the mining industry to model ore types, predict process performance and identify potential recovery issues ahead of time. However, most geometallurgical assessments are based on bench- or laboratory-scale analyses of relatively sparse samples, leaving most of the orebody characteristics known only by inference until the rocks are actually mined. In this pilot study, we test drone- and tripod-based hyperspectral imaging for mapping mineralogy across mine highwalls, dumps and leach pads. The results show that hyperspectral imaging can successfully map the types and distribution patterns of key minerals (especially carbonates, sulfates, clays, other phyllosilicates) and other important features (such as lixiviant ponding on leach pads), bringing geometallurgy into the field to provide crucial inputs to process decisions.

By S. F. Willey

The difficulties encountered in justifying replacements for over-age mobile mine equipment at the Gay Mine are common to most mining operations. More critical management reviews, resulting from ever rising capital expenses, increased such difficulties. These increased difficulties are especially apparent to those who are primarily operators and are not statisticians, mathematicians, or computer oriented. The Gay Mine is located 17 miles east of the town of Fort Hall in southern Idaho. This open pit operation annually supplies the J. R. Simplot Company and the FMC Corporation with 1.5 MM - 2.0 MM tons of phosphate ore. Stripping ratios average approximately three bank cubic yards of waste per ton of ore mined. The mobile mine equipment fleet consists of ten 24 yard scrapers; twenty-one 30-50 ton end dump trucks; four 32 42 yard shovels; fifteen dozers in the D-8 and D-9 classes; and three road patrols. Equipment replacement is based on the results of evaluations made on individual units. Authorization of capital expenditures for equipment replacement is dependent upon a favorable profitability index (true rate of return on investment) plus a favorable payout time. The system is based on cash flows and requires the determination of (1) the net cash outflows in the form of capital expenses plus (2) the expected cash inflows resulting from reduced expenses and depreciation tax credits. After adjustments for taxes and the time value of money, the net amounts are used to calculate the required indices. The basic elements for the system related to the replacement of mobile mine equipment include: (1) the determination of dollar penalties to be expected from the continued use of aging equipment; (2) the selection of equipment that will provide the greatest return on the investment dollars; (3) the quantification of the expected savings; and (4) the calculations of the prescribed indices. Inadequacies inherent in previous evaluating methods led to the search for more

Jan 1, 1972

By John D. Grothe

Laboratory experiment as a basis of commercial plant design has been the subject of much analysis and thought and on which a large number of articles and papers have been published. We would be forced to choose between an unduly brief exposition if we wanted to cover it completely, or no exposition at all. We must therefore concentrate upon the essentials without ignoring at the same time too many of the qualifying factors which, by the choice of what we want to examine, may become side issues. In doing so, we do not imply that these side issues are therefore any the less important. In every case, what is said here applies with almost equal force to the pilot plant which may be necessary as it does to the commercial plant. In discussing a recent paper by Derek C. Shelton on the Santa. Barbara Mill in Chihuahua at a meeting of the Inst. of Mining & Metallurgy (London), D. J. Ottley said on the matter of relating laboratory results and small scale tests to full scale plant results that he would like' to draw the attention of members to the great difficulty of scaling up mineral dressing plants and processes. He felt that this was an important yet neglected subject which merited considerable fundamental scientific attention from mineral dressers and plant design engineers in particular. How much of this fundamental scientific attention has, as a matter of fact, been accorded to the subject, mainly by our sister profession, Chemical Engineering. The close similarity to chemical engineering problems that we meet, particularly in hydrometallurgical operations, suggests that Chemical Engineering publications offer a rich source of information and discussions of methods useful to us. We have only to think of pressure leaching, ion exchange, liquid-liquid extraction, precipitation and so on, all problems in chemical engineering unit processes or of the new Freeport Sulphur Nickel plant in Cuba or the Sherritt Gordon plant and many others.

Jan 1, 1960