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By Yuting Xue

The classification of rock and coal will assist in automated coal rib rating and shearer horizon control, and is studied with machine learning techniques in this work. A database of rock and coal images is created by filtering photographs taken by researchers from the National Institute for Occupational Safety and Health (NIOSH). The classifier was trained with patches extracted from the coal and rock images, and an accuracy score of 0.9 was obtained. The trained classifier was then applied to classify rock from a new coal rib image with three rock layers of different thicknesses, and good agreement was achieved. The results demonstrate that it is promising to use machine learning techniques and rib images for rock and coal classification.

By U. Thorley

This paper presents an overview of surface mining activity in the Canadian oil sands and how the mine operators interact with the province of Alberta's Mine Financial Security Program (MFSP), which took effect April 1, 2011. The MFSP approach to reclamation assurance results in the government of Alberta sharing a portion of reclamation liability through the majority of an oil sand mine's life. In order to determine the potential fiscal magnitude of this shared liability, an examination of the expected costs of oil sands reclamation activities through a study of corporate asset retirement obligation (ARO) liabilities and other corporate disclosures is presented. The province of Alberta's Environmental Protection Security Fund (EPSF), which formerly secured oil sands mine reclamation activities is discussed. Reclamation costs in the oil sands are poorly understood. The MFSP provides what it characterizes as a conservative estimate of C$75,000/ha, while corporate disclosures by Canadian Oil Sands Ltd. place expected costs at C$180,000/ha. There is significant risk associated with the apparent uncertainty surrounding reclamation costs.

Jan 1, 2012

By Ken Fucik, Jorge Briceno, Bjorn Bjorkman

In 1993, a lawsuit was filed on behalf ofnative groups in Ecuador against Texaco for environmental damage resulting from petrole­um production activities which had occurred many years earlier. The basis of the lawsuit at the time was that Texaco had failed to perform its foreign activities in the same manner that it operated in the U.S. No environmental regulations were in existence in Ecuador at the time of Texaco's operations. Also in 1993, a lawsuit for over $3 billion Australian was filed on behalf of native New Guineans for alleged environ­mental damages and health impacts that occurred as a result of BHP's operations at its Ok Tedi Mine. Since then, Royal Dutch Shell has been subjected to major criticism for environmental damage caused by its operations in Nigeria. A more recent report has criticized Shell for groundwater contamination of an aquifer in Turkey. Southern Peru Copper is now defending against a lawsuit filed by citizens exposed to air emissions from smelter operations in Peru. In all of these cases, much of the alleged damages occurred many years previous. A defense com­monly made by the companies has been that operations were conducted according to the standards in place at the time. This has not limited the lawsuits nor minimized the international publicity which has followed. While such lawsuits have been common in the U.S. for many years, their appearance in other nations have pointed out a growing sense of worldwide concern with regard to the impacts of industrial operations. Of particular concern is the fact that lawsuits have been filed in countries that have up to now had few, if any, environmental regulations. The regulatory environment has been a part of most U.S. business operations since the early 1970's. Now, however, envi­ronmental regulations are starting to be implemented in many less developed nations. This has led to the formulation of a myriad of standards and approaches to environmental regulation around the world. For multinational companies, the challenge becomes one of anticipating the level of compliance that will be required to minimize liabilities not only for the present but also in the future. The purpose of this paper is to provide some guid­ance with regards to choosing a level of compliance, particular­ly as it applies to water quality.

Jan 1, 1996

By David Green

Outokumpu introduced Flash Flotation in the early l 980's for the recovery of floatable material from grinding circuits. The devel­opment came as a result of surveys made in the company's own concentrators, initiated to find ways of improving recoveries with increasingly complex and lower grade feeds. Hydrocyclones make a separation on the basis of particle size and mass, resulting in the "over collection" of fine grained, high S.G. particles. Minerals such as pentlandite, galena and gold are easily caught in the circulating load around the mill until they are overground and rendered more difficult to collect. In the case of downstream flotation this may simply involve a reduction in the rate coefficient due to the finer sizes or, as is commonly experienced in gold operations, the mate­rial is slimed and coated onto non-floating gangue and is eventual­ly lost to tails. At the time of Outokumpu's plant surveys, it was a relatively common practice, particularly in Pb operations, to have a flotation section fed directly from the secondaiy mill discharge. This is called unit flotation and certainly provided an improvement but very high wear rates and frequent sanding out of the cells was com­mon. The development of the SkimAir® Flash Flotation cell by Outokumpu provided a subtle but quite dramatic departure from the unit cell approach. Now it was possible to feed cyclone under­flow into a special purpose-built flotation machine and recover a final grade concentrate from the grinding circuit (see Figure I). The cell was designed to handle the coarse circulating load, per­mitting the coarsest fractions to be short-circuited back to the mill and retain the floatable sizes for a nominal time of 30 seconds to several minutes. The short retention time was possible largely due to the relatively clean content of the cyclone underflow stream. This means that the fine gangue is not present except in small quan­tities and most of the fine to mid-size paiiicles are higher S.G. and more likely represent valuable mineral. This condition provides for very high rate coefficients. Typical operations would recover 40-60% of the valuable mineral in this fashion and improvements in recovery were typically from 2-5% for sulphide minerals to the 5-20% range for gold and silver.

Jan 1, 1998

By D. W. Scott, D. G. Minnes

Introduction Ontario's diverse industrial mineral resource base includes structural minerals such as sand and gravel, crushed stone, building stone, clay, shale, limestone, and dolostone. These resources are used to produce aggregates, brick, metallurgical stone, fillers, cement, lime, and other construction materials. The majority of the operations are in deposits of Palezoic and Quaternary age in southern Ontario, close to the major markets. Province-wide, there were more than 140 Mt (154 million st) of aggregates produced in 1985. About 115 Mt (128 million st) of that was produced in southern Ontario with the rest being largely from Crown land in northern Ontario. Structural industrial minerals account for more than 80% of the value of total industrial mineral production. The remaining 20% is accounted for by the nonstructural minerals, such as salt, which is produced in the southwestern part of the province. A host of other nonstructural industrial minerals are known. Production, though, is currently restricted to calcite, gypsum, quartz, talc, nepheline syenite, and byproduct metallurgical sulfur products (Fig. 1). Major production is close to the large markets of urbanized southern Ontario and the northeastern and northcentral US. With an abundant variety of industrial mineral resources and the large population within 650 km (400 miles) of most deposits, the market offers great potential. Ontario's nine million people accounted for about 35% of Canada's entire $476.3 billion gross domestic product in 1985. This equates to about one-third of the nation's buying power being within a 200-km (125-mile) radius of Toronto. This major concentration of industrial and economic activity has resulted in a well-developed industrial minerals industry that fulfills most of the structural industrial minerals demand in Ontario. Nonstructural industrial minerals are similarly well placed to compete in this high demand area. Although Ontario manufacturers still import some of these materials, Ontario products are achieving significant market share. And, they serve the needs of neighboring provinces and states. Present production and trends Ontario has traditionally produced significant amounts of industrial minerals. This produc¬tion had a value of $956 million in 1984 (Table 1). Structural materials production in 1985 and 1986 approached or exceeded levels not seen since the early 1970s. Many new products have been developed using these raw materials. The industry is becoming concentrated in the hands of several large companies, mainly four large cement com-

Jan 12, 1987

By T. E. Mccandless

Detrital minerals of mantle origin have been found in the Green River Basin of Southwestern Wyoming (Figure 1). Pyrope, pyrope-almandine, and chrome-bearing clinopyroxene and orthopyroxene occur on the antmounds of Pogonomyrmex Occidentalis. These antmounds are a common sight throughout the western U.S., and were used by early paleontologists as fossil mammal collection sites. The mound is composed of two types of material; (1) soil excavated during the digging of the nest below the surface (maximum depth 3 meters) and (2) larger grains collected from the surface and placed on the mound, probably to prevent erosion. The selection of grains to armor the mound seems to be based largely on the mean diameter of the grain, with other factors such as weight, sphericity, roundness and composition in decreasing order of importance (Wheeler and Wheeler, 1963). The minerals of this study happen to fall within that mean diameter range. The garnets are found on the mounds as 3-6 mm diameter subrounded to subangular grains. The pyroxenes are also 3-6 mm in diameter and are most commonly subangular laths. The minerals themselves show evidence of abrasion, such as frosted surfaces and rounded edges. Orange peel texture is present on some of the grains, which suggests that kelyphitic rims were once present, but have been removed. Also, no similar minerals were found in sieved soil auger samples to depths of 2 to 6 meters taken near the antmounds. These observations imply a distal rather than proximal source for the minerals. Lamproitic rocks of upper mantle origin are found bordering the "Green River Basin. The best known are the Leucite Hills, a series of ultrapotassic volcanics found on the north flank of the Rock Springs Uplift (Carmichael, 1967). Minor occurrences of mica peridotite and ultrapotassic volcanics are also found on the western end of the Uinta Mountains in Utah (Best, et al, 1968). None of these rocks are known to contain minerals like those on the antmounds. The garnets are comprised of purple chrome pyrope, red chrome pyrope-almandine, and pink to orange low chrome pyrope/pyrope-almandine. Oxide statistics for these groups are summarized in Table 1. These three groups are distinct when their Cr203 values are plotted against magnesium number (Figure 2). The chrome pyropes are highest in Cr203 (1.28-2.66%) and have high, restricted Mg number values (0.781-0.826). The chrome pyrope almandines have similarly high Cr203 (1.29-2.62%) but a lower Mg number range. The low chrome pyrope/pyrope-almandines have the lowest Cr203 content (0.09-0.73) and the widest Mg number range (0.534-0.836). Using the classification scheme of Dawson and Stephens (1975) the chrome pyropes are most similar to garnets derived from kimberlite and from garnet lherzolite, websterite, and harzburgite xenoliths in kimberlite. The chrome pyrope-almandines and the low chrome pyrope/ pyrope almandines are similar to garnets derived from eclogite nodules (Figure 3).

Jan 1, 1984

By Jürg Künzle

Underground construction is a matter of dealing with the inherent uncertainty of subsurface geology. If the encountered conditions are less favorable than the expected ones, the execution of excavation, support, ground treatment or lining works is likely to require more or different efforts than anticipated, thereby delaying the works and increasing the costs. The 2019 first edition of the FIDIC Emerald Book model contract (FEB) addresses many of the issues to which underground works give rise, including those related to differing site conditions (DSC). This paper examines how under the FEB disputes arising from or in connection with DSC could or should be avoided.

Jun 13, 2021

By Gunjan R. Bhattarai, K. Bhattarai

Applications of machine learning and robotics in the tunneling industry are still nascent. Research and development are ongoing in TBM guidance; prediction of TBM cutter wear and tunneling induced ground deformations; and robotic arms for segment installation, inspection, cleaning, and maintenance of TBM cutting tools. This paper presents a case study of geological profile reconstruction using multimodal machine learning. The results from this study can aid the development and application of multimodal AI technologies to generate data reports and geological profiles in real time, taking voice recordings, photos, or videos obtained directly from the field as inputs.

Jun 23, 2024

By Doug Harding

The Metropolitan St. Louis Water District’s Project Clear is a 28-year program targeting wastewater capacity throughout St. Louis, MO. The extensive program includes the Jefferson Barracks Tunnel, running parallel to the Mississippi River at 2 m ID and 5,400 m long. A rebuilt Robbins Main Beam TBM began boring but hit challenging conditions about 2,400 m in, including water inflows. A larger 4.1 m Robbins Main Beam machine will complete the remaining 3,050 m in limestone, dolomite, and shale. The TBM will utilize a high-powered, high breakout torque cutterhead along with enhanced 360-degree probing & grouting capabilities to detect any karst formations.

Dec 1, 2022

By Roberto Carranza

The planning of experiments and the importance of statistical interpretation of the results have been recognized for years by scientists and engineers. The Factorial Design of experiments is among the various methods used for this purpose and is being widely applied in all branches of research and production. The basic principles of this tool have been described in detail (1, 2, 3, 4) and several examples of its application in various fields have been published (5). In recent years the mineral industry has also used Factorial Design to improve the efficiency of research, testwork and plant operation (6, 7, 8, 9). This method permits for a qualitative determination of the influence of the variables studied in a process and also a qualitative measure of the interaction of the variables. By graphic means or derivative methods, one may also establish the optimum conditions of the process (ibid 7, 8, 9). It is desirable, however, to develop mathematical methods to evaluate quantitatively these effects and restrict the optimization to the practical limitations of the variables. It is also convenient to adopt a notation system to generalize the Factorial Design.

Jan 1, 1971

By Mike Moody

"No matter what type of ore is being extracted from a mine, mucking with front loaders can be accompanied by wet fines that cling to every surface. Once loaded into a hopper or conveyer transfer chute, viscous material can quickly build up on the walls to create bottlenecks, clogging the chute and causing expensive downtime.Clearing material from hoppers, chutes, bins and vessels can be done using manpower and tools on hand, but safety experts recommend considering a solution that prevents exposing workers to potential hazards. Operators at modern mining sites, such as the Eagle Mine, located in Western Marquette County of Michigan’s Upper Peninsula, understand that using specialized equipment reduces worker exposure, offers the safest mode of production and provides the most cost-effective lasting results.“Safety is a top priority for us,” said Ted Lakomowski, lead reliability technician at the Eagle Mine. “When we experienced clogging and downtime at the processing mill, the crew naturally swung into action to resolve it, but we immediately sought a safer long-term solution.”Stope mining for nickel and copperOwned by Lundin Mining, a globally diversified base metals mining company headquartered in Toronto, ON, Canada, the Eagle Mine is the only primary nickel mine in the United States, producing 1.5 percent of the world’s total nickel production. The first operation permitted under Michigan’s Part 632 Non-Ferrous Mineral Mining Law, it opened in 2014 and is expected to produce 163 kt (360 million lbs) of nickel, 134 kt (295 million lbs) of copper and small amounts of other metals over its estimated nine-year lifespan.The company extracts approximately 2 kt/d (2,200 stpd) from the underground nickelcopper mine using a bench-and-fill stoping process. Accessed from the surface by specialized underground trucks, the vehicles carry about 45,400-kg (100,000-lb) loads through a 1.6-km (1- mile) long and 5.4-m (18-ft) diameter ramp shaft descending into the earth at a 13 percent grade. Stoping is a bottom-up method that involves systematically blasting columns of loosened ore that is then mucked by front loaders into trucks and backfilled using cemented and uncemented rockfill."

Aug 1, 2019

"What is your history and how did you get involved in mining?Like many SME members, I came from a mining community with a family history in mining, in my case Walkerville, MT. Both of my grandfathers were underground miners. My father was a miner for a short time. He later sold drinks to the miners. Unfathomable by today’s standards, my dad would pick up the miners’ checks at the pay office and have them cashed and waiting with a shot and beer for the miners when their shift ended. My mother was a nurse, who from time to time, would patch up an unfortunate miner. I remember walking past multiple picket lines on the way to and from grade school, watching homes being boarded-up. I grew up with a deep respect for the critical relationship between labor and management.I had no intention of going into mining and initially set out to pursue a career in chemical engineering. But I attended my first two years of engineering at Montana Tech, due to the proximity and affordability. This is where I met Dr. Tom Finch, a mining professor who taught statics to the engineering students. After a coaching session in a hallway, half way through my sophomore year, I switched to mineral processing engineering. In his colorful way, Professor Finch advised me that, “You do not want to make #@*!! erasers and #@*!! Jell-O the rest of your life go talk to the guys in mineral processing.” He was very persuasive and here I am today.How about your involvement with SME?I encountered SME out of school and a little later in my career. Terry Maio and Jim Arnold invited me to local section meetings in the Missouri Lead Belt. That was my first exposure to the technical programming and relationship building that was possible at the local level. After Ozark Lead shut down and I relocated to Nevada, Rich Johnson, Scott Barr and Dave Collins encouraged me to attend my first annual meeting in Salt Lake City, UT. I joined SME at that time and was fortunate to be engaged by members like Art Schweizer and Jim Arnold, and I soon began the leadership progression for the Mineral & Metallurgical Processing Division. Since then, I have supported SME at the national and the local level serving in multiple roles and capacities."

Mar 1, 2017

By Zoë Dugdale, Gerald Poplin, Tim Bauerle

"Fatigue presents several challenges for the mining industry. Depending on the specific occupation, daily work or operational setup on any given mine site, mining jobs can have a fair amount of labor-intensive tasks mixed with monotonous and repetitive duties. Combined with the long working hours and shift-work schedules of mining work, the prevalence of fatigue in mine workers may seem rather unsurprising.Mining is certainly not alone in facing the challenge of addressing worker fatigue. Indeed, many of the characteristics above mirror the similarities of fatigue in other industries, such as health care, aviation and security. To the extent that fatigue in mining acts like fatigue in any other industry, then any fatigue management applications, trainings, or interventions in existence can be borrowed from other industries and applied to mining in a cookie-cutter approach. However, some have argued that mining in particular is especially susceptible to increases in the prevalence of fatigue beyond the characteristics listed above due to the multifaceted combination of factors in mining environments associated with fatigue: dim lighting; limited visual acuity; hot temperatures; loud noise; highly repetitive, sustained, and monotonous tasks; shiftwork; long work hours; long commute times due to mine site remoteness; early morning awakenings; and generally poor sleep habits (Canadian Centre for Occupational Health and Safety, 2012; Legault, 2011). Legault (2011) in particular argues that it is the combination of these factors simultaneously that can make mineworkers particularly susceptible to sleep deprivation and fatigue in comparison to other industries where these factors are often not present all together. If fatigue looks and acts different in mining, as others have argued, more research is needed to determine if, how, and why worker fatigue might need to be managed differently in mining.While the burden of fatigue on the mining population has not yet been evaluated thoroughly, methods and measures of fatigue management remain a popular point of discussion. Many commercial suppliers and consultancy groups have begun to develop technologically based fatigue monitoring systems (McMillian, 2013). Some technologies can monitor vehicle operators for indicators of wakefulness, such as percent eyelid"

Jan 3, 2018

By C. McAllister, D. Preece, J. Berendzen

"The Multiple Blasthole Fragmentation (MBF) model models multiple explosive charge contributions and the effect on fragmentation of delay timing with its associated scatter for each blasthole. The model uses near-field blast vibration attenuation parameters and the ground p-wave velocity as inputs for part of the in situ rock property to model rock fragmentation. It models most blast design parameters explicitly and simulates the effect of wave reinforcement due to the interaction of simultaneously arriving waves or diminishing cooperative contribution from long delay intervals between charges within a blasthole or among blastholes. The fragmentation size is calculated at three-dimensional grid points within a blast, and the fines and oversized blocks are treated explicitly. The model takes a surveyed irregular geometry of the free face of a blast as the calculation boundary.This paper presents a case study on applying the MBF model at an openpit mine. Near-field vibration measurements from signature hole blasts were conducted to obtain the stress-wave magnitude and attenuation parameters as well as ground sonic velocity. A production blast was then monitored with the corresponding fragmentation measured, serving as site-specific inputs to the MBF model. Various blast design scenarios were then simulated to develop ones that provide better fragmentation to improve mill throughput for the mine. IntroductionThe semiempirical fragmentation models currently found in the literature (Cunningham, 1987; Lownds, 1995) cannot explicitly model contributions from multiple blastholes with varying delay intervals. Most of these models are not three-dimensional. Furthermore, these models predict an average fragmentation size within a volume surrounding a blasthole and use the average size to generate a size distribution over the volume. The percentage of fines and oversize blocks is included in the distribution. Typically, such models are inadequate for predicting fines and oversize blocks (Cunningham, 1987)."

Oct 1, 2016

By F. Dehghani, B. Rezaie, T. Ghosh, A. Sachan

Comminution is an integral part of the mineral extraction process. However, the influence of the comminution method (ball and rod mills) on silica and magnetite particle shapes has not been substantially investigated. Shape parameters for fractions of -250+212, -150+125, and -106+75 μm sizes were examined utilizing a scanning electron microscope and a Clemex vision PE image analysis system. The silica particles displayed higher elongation and flatness parameter values for rod mill products, but roundness and relative width parameter values of rod mill products are less than that of the ball mill products. Magnetite particle elongation and flatness parameter values of ball mill products in fraction sizes of -250+212 and -106+75 μm are larger than rod mill products, but roundness and relative width parameter values of ball mill products are smaller than rod-mill products, but for the -150+125 μm size range the result is converse. Furthermore, particle elongation and flatness increased with decreasing particle sizes of silica, whereas, roundness and relative width decreased for both Ball and Rod Mills. In case of magnetite, ball mill products displayed an increase of flatness and particle elongations with decreasing particle sizes but flatness increased and roundness and relative width decreased. Similarly for rod mills, magnetite fractions of -150+125 μm were found to have the largest values of elongation and flatness. INTRODUCTION Comminution alters the size and shape, causes lattice distortion, changes chemical composition, surface area, surface-free energy, and polymorphic transformation of all materials. The quantity and quality of such changes depend on specifications of the material feedstock, the type of mill being utilized, the specific energy input, ambient temperature, and environmental pressure [1]. The shape difference between the milled products depends on different grinding mechanisms and the respective breakage principles that these mechanisms depend on [2, 3]. With decreasing particle sizes, the nature of the particle surface become crucial [1]. The influence of the breakage technique has been found to be non-trivial and heavily dependent on the type of grinding mill used for particle size reduction [4]. Shape is an important industrial parameter for predicting particle behavior in downstream processes. The shape parameter affects the way particles burn, compact, are recovered, flow in fluids, sinter, float, agglomerate, fluidize, interact with pulmonary tissue, cut, abrade, react with chemicals, form structural materials, and retain and permit fluids to flow [5, 6]. The distribution of particle sizes and shapes are important for mining, civil and chemical, pharmaceutical, and various other industries with interest in the population modeling of atmospheric dusts, smoke, and grit [1, 3, 6]. The shape parameter not only affects the chemical, physical, surface properties of particles but is also important for downstream processes [5, 6]. Image analysis has been found to provide detailed information about size and shape of the particles and can be used for the control of product quality [4].

Jan 1, 2019

By Gary P. Thomason

We have all heard a great deal about how various projects were financed or certain companies were successful in obtaining a bank loan. There are many more projects and companies who fail to get the money they need. At least a portion of these failures, and a large percentage of the frustrations connected with even the successful financings, are a result of not understanding the process of obtaining money. Recent years have seen a proliferation of sources available to finance minerals operations, but let me assure you that these represent only a minor portion of the minerals financing market. The fundamental source of borrowed money to almost all minerals related companies remains the banks. Therefore, understanding the "Loan Approval Process" can easily mean the difference between getting the money or not. In the following pages I hope to provide some insight into what I define as the loan approval process. Having pre-offered my definition, I intend to delineate the various stages of the process and the planning and information I believe should be contained in each. My ultimate goal is to help you think like a banker and, in so doing, stay on top of the process so that you can successfully obtain the funding necessary for your projects.

Jan 1, 1983

By D. Arku

The increased use of sensors to facilitate automation has led to an explosion of data. As data sets grow in size, their use becomes more complex. Therefore, there is an incentive for reducing the size of the datasets, as long as this does not compromise information gleaning. With this in mind, this project explored basic aggregation as a viable alternative to amassing large amounts of data. The goal of the project was to determine if one would arrive at different conclusions had they analyzed aggregated data instead of raw data. In a mine, operational data is typically used for tracking process statistics, correlation between factors, autocorrelation and multivariate models (for a factor of choice). Therefore, this project compared results from such analyses when it was conducted with aggregated data (AD) with the results of analyses conducted with raw data (RD). The data consisted of one-minute-apart readings from a semiautogenous grinding (SAG) mill on the horsepower, feed rate (tons per hour), rotations per minute (rpm), noise, recycle (tons per hour), density (% solids) and bearing pressure (psig). This data was aggregated by averaging five and 10 continuous (one-minute) observations. Changes in statistical measures between the two approaches were typically within 5% of each other. Differences in correlation coefficients between RD and AD(s) were also within this range. Autocorrelations present within RD were preserved in AD, as long as the time lags were scaled for the amount of aggregation. Regression and neural network models were also developed for power consumption. The prediction performance of developed models was similar whether one used raw data or aggregated data. Overall, it appeared that aggregating the data based on 5- or 10-minute time spans would not have resulted in conclusions (from simple or complex analyses) being different from using raw data. In other words, whether one had used raw data or aggregated data, the conclusions would have been the same, suggesting that time domain aggregation, a common industry practice, is a good alternative to storing high-density data in this case.

By R. E. J. Putman

Rising demand, artificial market conditions, increased overseas competition, and a fluctuating international situation have brought ever increasing pressures to bear on the nonferrous metals industries, and particularly in the United States, Although capacity is being expanded by the construction of new plants and the development of new ore deposits, increasing attention is being focused on the possibilities of improving the performance of the existing installations and of getting the most out of the new equipment now installed. At first sight the task appears formidable. Based on raw materials which are nonhomogeneous, and possessing characteristics which are hard to quantify, even the processes by which the values in the ores are concentrated and extracted are in many cases not fully understood. The necessary analytical equipment and transducers demanded by these industries have also been slow in development and their earlier absence has hampered the application of modern control technology, This is reflected in plants which have been designed for ease of manual rather than automatic control, and in which the application of control techniques at first sight appears economically prohibitive. However, in any industry progress often comes only in small steps, It may be that by the wise choice of limited objectives and perhaps only partial solutions, substantial improvements in plant performance can be implemented now, and with only a modest investment. If modern control equipment is chosen of the type which can be reprogrammed, advantage can be taken later of more sophisticated solutions as the technology of the industry advances. This task of improving plant performance can and must be commenced even though our knowledge is incomplete. The experience of a related mineral consuming industry, with similar problems in the past, can be encouraging.

Jan 1, 1967

By Gleason

"From June 16 to 19, more than 1,400 tunneling and underground construction professionals gathered in Chicago, IL for the bienial Rapid Excavation and Tunneling Conference (RETC). There, they were greeted by a full technical program and an exciting exhibit hall that provided a comprehensive look at the world’s bustling tunneling and underground construction industry.The successful conference was a reflection of the industry itself, which is to say, busy. As much of the world has begun to focus on creating a cleaner and greener environment, the global tunneling industry has seen an uptick in infrastructure projects move from design-build to construction phase. With a global shift away from the use of fossil fuels, major cities around the world are looking to increase public transportation options, which leads to the need for more transportation tunnels. And as urban populations continue to grow, the need for clean water calls for more tunnels, and as urban footprints continue to expand, the need to increase and update combined sewage overflow tunnel grows with them.During two and a half days, more than 20 sessions covering all of these topics were presented at the Hyatt Regency in Chicago, many to packed rooms in which every seat was taken and people were standing along the side and back walls.RETC is a biennial conference and one of the largest in the North America for the tunneling and underground construction industries. As such, it hosts a robust exhibit floor. This year 172 vendors occupied 205 booth spaces. The exhibit included everything from tunnel boring machine manufacturers, like Robbins and Herrenknecht, to the companies that supply all kinds of parts and services to the industry."

Sep 1, 2019

By Vince Saporito

Miners work in dangerous terrain, around the clock, with heavy equipment. Is there room for improvement in safety and standardization in the mining industry? Recent history would suggest there is a need for action. At a 2011 Spring Thaw conference in Denver CO, one speaker commented, ?We are having a number of incidents with workers getting ?pulled? into rollers or ?trapped? at transfer points when trying to manually clean (it) while the conveyor is still in motion.? It?s a troubling thought. These actions are specifically prohibited under U.S. Mine Safety and Health Administration (MSHA) regulation 57.14202. Another official from MSHA earlier this year indicated with today?s technology and policies presently in place, ?we should not be repeating the same incidents and violations year after year as we currently do.? But we are doing exactly that.

Jan 1, 2012