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By J. Ragot, D. Maquin, N. Heraud

Acquisition of coherent and representative data about the state of processes remains a major problem of process control. This paper proposes an approach that ensures coherence in measurements on an operational industrial process. The basic technique employed relies on balance equilibration of resource mass flow. An interesting particularity of the set up is the ease with which it can be adapted to check productivity or detect sensor failures. In the case of sensor failure, it suffices to examine the evaluations before and after balance equilibration. The algorithm was tested by means of computer simulation using data from an industrial metallurgical flowsheet.

Jan 1, 1992

By M. A. Weaver

This paper will investigate the historic and present state of the bituminous coal industry within the Commonwealth of Pennsylvania, with special emphasis on surface mining operations. It will address pertinent parameters such as production, markets, quality, number and size of operations, price, and productivity from a statistical viewpoint. In addition, relevant statistical parameters of select areas of the Appalachian Coal Region will also be presented and discussed.

Jan 1, 1989

By Harold Rees

[This report supplements and brings up to date a paper prepared earlier this year for presentation at the Eleventh Pan American Railway Congress to be held in Mexico City, October 18 to 31, 1963. In order to acquaint the reader with the background of this project practically all of the first paper is included in the report.]

Jan 1, 1963

By Ravi Sahu

"In the global mining industry, there are those who seem resigned to the fact that the mining industry has always operated according to certain time-tested principles that don’t involve jumping on every new technological trend. Others expect that mines will soon have autonomous electric vehicles running around the clock. The truth lies somewhere in the middle. In business, as in life, that is usually the best path to follow.The instant access to people and information provided by 21st-century technology continues to push businesses in all industries toward greater efficiency and unheard-of levels of modernization. And in the world of mining, the embrace of advanced technology is all about managing risk.However, even in this age of digital information overload, some mine sites still require employees to physically download data from individual trucks to monitor payload data and inspect road conditions using a clipboard. What’s more baffling is that other mine sites still have no way of tracking tons moved at all.This isn’t due to a lack of innovation in the industry. Quite to the contrary, there is an abundance of new technology available that provides real-time monitoring of vehicle movements and tracks road conditions without the intervention of people. So why are owners reluctant to embrace advances in mining tech?Gauging the value of changeSurvey data has traditionally been captured by ground laser scans and LIDAR systems. A mine site surveyor would drive around the pit with a truck-mounted scanner to generate a point cloud. This process would be completed every few days and would take an entire day.The many cons of this method far outweigh the pros. First, it provides no visual data. If an operation has moved beyond the roller wheel and tape measure, visual pit models and LIDAR scans are typically completed once every six to 12 months by an aerial flyover, but such sporadic information gathering isn’t likely to result in the most actionable data. Moreover, given the high cost (in terms of both money and time), the numerous safety and liability issues, and the lack of flexibility in scheduling, manual processes are more trouble than they are worth.Overall, while miners are excellent operators who value innovation, their employers often try to outsource it or acquire innovators instead of investing in existing technology that can improve current operations. It is a never-ending dilemma:"

Jan 5, 2018

One of the biggest challenges for the mining industry is, quite literally, how to the keep the equipment rolling. There is a limited amount of companies that manufacture the 4.2-m- (14-ft-) tall, 5,670-kg (12,500-lb-) tires needed for the haul trucks that are approaching the 362 t (400 st) pay-load class, such as Terex?s MT6300-AC and Caterpillar?s 797F. And, while these might be the most impressive tires, they are not the only ones that are in short supply. The shortage of tires has affected just about every kind of machine, and the demand for those tires has been extremely high for more than five years with no end to the shortage in site. American Tire Corp. (www.americantire.us) is one of the companies working to supply tires to the mining industry. It announced that the demand for its 1.6-m (63-in.) tires that have a zero failure history globally is great and that the company signed contracts worth more than $500 million at MinExpo. A relatively new player in the field of large tires for mining equipment is Titan Tire Corp., (www.titan-intl.com), a subsidiary of Titan International Inc. It shipped its first 1.6 m (63 in.) off-the-

Jan 1, 2008

By M. Spangler

FirstMiss Gold installed a supervisory control system based on Pavilion Technology's Process Insights neural network software and Oil System's PI data historian. The primary goal of the system was to control the acid preconditioning circuit. However, our first successful control loop was on the limestone feed rate to the neutralization circuit. The information gained by modeling these circuits and the better control provided by the system has resulted in reagent savings of over $80,000 per month.

Jan 1, 1995

By V. O. Tenorio

The implementation of autonomous technologies for production in surface mines demands changes in the existing monitoring and control systems. The present study deals with the concepts involved in the development of a decision support system (DSS) for the supervision of a combined fleet of manned and unmanned equipment operating in a surface mine. The project was carried out as part of an autonomous mining program that lasted from early 2006 until the end of 2008. The objective of the DSS was to achieve short-term planning goals while maintaining safe working conditions. Supervisory tasks become more complex when several autonomous vehicles operate simultaneously alongside manned equipment. The operation center where the DSS was installed allowed autonomous vehicle operations to be controlled while tracking technology reliability experiments performed on control display interfaces and interaction provided design parameters for more complex supervisory systems for autonomous mines. Mining Engineering, 2011, vol. 63, no. 11, pp. 80-86. Official publication of the Society for mining, metallurgy and exploration, Inc.

Jan 1, 2011

By Jey K. Jeyapalan

A characteristic common to most tailings dam failures caused by earthquakes or excessive rain storm is that the tailings tend to liquefy and flow for substantial distances as a viscous fluid, with the potential for extensive damage to property and life. Failures of El Cobre, Chile (1965), Mochikoshi, Japan (1978), Aberfan, Wales (19661, Buffalo Creek, West Virginia (1972) are examples of such catastrophic incidents. In these four incidents more than 400 lives were lost, and the loss of property was approximately $200 million. In order to be able to assess the potential for damage in case of such a failure, it is necessary to predict the possible extent of flow slide movement. This paper discusses simple procedures for performing such analyses. Also, in order to illustrate the use of these analysis procedures in tailings dam design, two case histories are analyzed.

Jan 1, 1982

By Lee Ann Arrington-Webb

Thiele Kaolin Co. has invested much time and money in achieving and maintaining its IS0 9002 certification. Through a regimen of process control and documentation, routine audits and a commitment to quality management, this kaolin producer is a competitive pigment supplier in a worldwide market. Background In 1987, the International Organization for Standards developed the ISO 9000 quality management system. This series of standards is used as a means to ensure customers that a quality management system is in place. Certification of a company does not mean that an individual product is of high quality. Rather, it demonstrates a supplier's ability to meet its customers' product and service needs. It also shows that a company has documented records to assure product consistency. The ISO 9000 system was begun in England during the early 1980s. During the mid-1970s, the British manufacturing industry was experiencing low quality. In an attempt to boost quality standards, the British government established the BS 5750 standards system. In 1987, BS 5750 was incorporated into ISO 9000. The ISO 9000 series consists of three levels of certification. ISO 9001 is the model for quality assurance in "design/development, production, installation and servicing." This standard applies to companies that rely on research and development to bring products that frequently change to market. ISO 9002 involves "production and installation" only. This standard is relevant to industries that produce a specific product according to specifications - either their own or their customer's. ISO 9003 is the model in "final inspection and test." This standard is the least detailed of the 9000 series. It is also the most applicable to companies that purchase, inspect or sort and resell. The quality system requirements for certification are outlined in the 18 elements of ISO 9002. These include: 4.1 - Management responsibility. 4.2 - Quality systems. 4.3 - Contract review. 4.4 - Design control. 4.5 - Document and data control. 4.6 - Purchasing. 4.7 - Control of customer-supplied product. 4.8 - Product identification and traceability. 4.9 - Process control. 4.10 - Inspection and testing. 4.11- Control of inspection, measuring and test equipment. 4.12 - Inspection and test status. 4.13 - Control of nonconforming product. 4.14 - Corrective and preventive action. 4.15 - Handling, storage, packaging, preservation and delivery. 4.16 - Control of quality records. 4.17 - Internal quality audits. 4.18 -Training. Continuous improvement, though implied in maintaining these requirements, could potentially be included in the quality system requirements in the next revision. The ISO 9000 requirements and documentation system is shown in the hierarchy pyramid (Fig. 1). A company's quality policy serves as the top of the pyra-

Jan 1, 1997

By V. R. Degner

Comments Summary It is very interesting to review the technical changes which have occurred in the industrial practice of minerals flotation over the past two decades. In 1972, worldwide industrial flotation was dominated by 'mechanical' flotation machines having an individual cell volume less than 500 cu.ft. Manufactures, such as DENVER Eqpt. Co., OUTOKUMPU, WEMCO, GALIGHER (AGITAIR), AKKER, and later DORR-OLIVER, produced flotation machines featuring a mechanical rotating impeller which served to mix pulp and air, prior to flotation, and to keep the solid ore particles in suspension. While sharing this common mechanical impeller feature, the machine design of the various manufactures differed in detail; particularly in regard to the vertical location of the impeller in the cell and the means by which flotation air was brought into contact with the pulp within the rotor mechanism. A review of the existing technical literature in 1972 would identify academic research studies, particularly at Columbia University (N. Arbiter, C, Harris ...) aimed at comparing flotation cell design concepts, of the various machine manufactures, on a hydrodynamic basis. These research studies were confined to very small, laboratory bench size, flotation machines, and the benefits of incorporating hydrodynamic considerations in the scale-up of the existing 300 cu.ft. mechanical flotation technology to larger cells was not commonly practiced industrially. Technological advances in minerals flotation, over the past two decades, have been influenced by a variety of economic factors including the increasing development of lower grade ore bodies, the attractions of producing a higher grade final concentrate, and the economy of tails retreatment to improve overall plant recovery performance, and flotation system “optimization" became increasingly important through the 1970-80 time period. The trend toward processing lower grade ores led to higher tonnage mill operations, and stimulated the development of the very large capacity mechanical flotation machine for roughing and scavenging duty. In 1972, the 500 cu.ft. size flotation machine was being pilot tested and introduced to the industrial market. Today, 1993, individual cell volumes of 1500-3000 cu.ft. are operating successfully throughout the world, and well planned plant test programs have concluded that the very large flotation machine can achieve the same metallurgical performance level of its smaller predecessor. The large flotation machine development record clearly credits the incorporation of internal cell hydrodynamic considerations in guiding the scale-up of the mechanical flotation machine to large sizes. This guidance eliminated, or reduced significantly, costly in-plant prototype machine changes which increase Dramatically with increasing flotation machine size. Early in the 1980's, at approximately the time that flotation machines in the 1500 cu.ft. class were being introduced into the market, it became evident that the availability of the very large mechanical flotation machine brought with it the need for a systematic means to "optimize" the flotation system by relating flotation cell size, row length (i.e. number of cells per row), and flotation rougher, scavenger, and cleaner system configuration to the economic objectives of the concentrators' operating management. Flotation system optimization consists of quantifying the flotation process performance using a suitable model which relates the kinetic response of the trace specie and the gangue material to the cell overflow, and produces a numerical relationship between product grade and value recovery. The computer analysis technique has proven to be an invaluable tool in determining the kinetic model coefficients which characterize a given application, and is also used to apply the resulting model to a proposed minerals beneficiation situation seeking to "optimize" the flotation system by relating metallurgical grade-recovery performance, flotation cell size, and circuit arrangement, to plant space, installation, and operating costs. It is interesting to note that these same computer based kinetic flotation analysis techniques can be easily applied to quantitatively evaluate the effect of different chemical reagent strategies, and flotation air transfer, on process performance for a variety of candidate feed ore types.

Jan 1, 1993

By R. Miller

Lowering our globe’s emissions is a major effort as we move toward a future net-zero carbon environment requiring significant investment in a new, low-carbon infrastructure, along with key market incentives to change. Industry will play a key part in this transformation, requiring expertise in both energy and emissions. Key elements of the de-carbonization strategy are: energy data, emissions reporting method, governance, de-carbonization project generation and drivers, the MACC, electrification, and the de-carbonization checklist. For a zero carbon future, it will be key for business leaders to understand decarbonization, anticipate technological changes, and implement new business me

Mar 2, 2022

By M. Liu

In-situ soil washing using surfactants shows great potential to remove hydrophobic organics from subsurface environment. Lab scale soil washing experiment were performed using Sodium Dodecylsulfate (SDS), an anionic surfactant, and anthracene, a highly hydrophobic compound. The results of this research show that solubility of anthracene increases linearly with an increase in SDS concentration above the critical micelle concentration. Furthermore, SDS can be effective in removing anthracene from contaminated sand.

Jan 1, 1992

By N. B. Aughenbaugh

A study was made to determine those petrographic parameters that are correlative with carbonate-aggregate quality as indicated by the Los Angeles abrasion and absorption tests. Samples collected at 28 sites in northern and eastern Indiana were analyzed petrographically, chiefly for void content, grain size, grain-size variation, grain shape, and grain interlock. Most of the sampled sites are in the belt of Silurian rocks of east-central and north- western Indiana. Though a few sites lie outside this belt, most of these have only a thin Devonian section above the Silurian. Three sites are non-Silurian and are included for comparison. Most of the samples studied are from Middle and Upper Silurian units. Both biohermal and nonbiohermal facies are included. The biohermal rocks are typically dense but vugular, finely crystalline granular dolomite. Nonbiohermal facies are porous, medium to coarsely crystalline, granular dolomite with dolomite rhombs The Los Angeles abrasion losses ranged from 20 to 46 per cent, the rocks in the eastern part of the state showing the higher values. Absorption tests indicate the same general quality trend. Comparison of petrographic studies with Los Angeles abrasion- and absorption-test results indicate the following correlations. (1) As per, cent of voids increases, quality decreases. (2) As average grain size increases, quality decreases. (3) Variations from mean grain size appear to have no effect on the quality. (4) As angularity and roughness of the grains increase, quality increases. (5) As grain-to-grain interlock increases, quality increases. Variations in the calcium-magnesium ratio have no apparent effect on aggregate quality, except as they affect the texture.

Jan 1, 1966

By P. B. Altringer

The Bureau of Mines conducted laboratory tests to develop a process for recovering a marketable grade of tungsten from the brine of Searles Lake, Calif. The brine contains only 56 parts per million of tungsten (70 ppm WO3). Using ion exchange resins synthesized by Bureau chemists, 98 percent of the tungsten was extracted from the brine and 92 percent of the tungsten vas recovered as a marketable iron-tungsten concentrate containing 44 percent tungsten as tungsten trioxide. Although major technical problems have largely been resolved, research is progressing to escalate testing in a process investigation unit to provide more reliable data for an economic appraisal.

Jan 1, 1978

By E. A. Rychkun

Introduction Minicomputers have been gaining acceptance in mining. Low cost interactive processing and plotting can now be controlled by geologists or engineers needing rapid solutions and specialized mining software in formats that allow noncomputer personnel to readily interact with computer processes. User-oriented programs maximize the use of interactive display features and graphics, as shown by the HP9845 minicomputer, a unit with portability, processing power, graphics capabilities, capacity, and peripherals such as plotters, digitizers, disk drives, and printers. Application Coal exploration projects require that much effort be spent determining coal volumes within trial pit limits. This determines a prospect's viability and potential. Adapting volume calculations to a computer has been limited, since it was difficult to create reasonable representations of complex coal seam geometry with a digital process. So many of the simple mechanical procedures needed to produce pit reserves are still performed manually by geologists and engineers. But with new minicomputers and their interactive graphics, it is now practical to accurately model complex structures without tedious calculations. GEOSEM (Geomin Seam Oriented Exploration System) is a computer system designed to analyze coal prospects. The system shows how a coal prospect, with complex geology, can be quickly analyzed, modeled, displayed, and evaluated for mineable reserves. Its interactive graphics allow rapid visual presentation of data, high-speed tabular reports, and precision plotting. The system is most effective when used by a geologist or engineer who selects the required operations and specifies relevant parameters via screen and keyboard interaction. Rolling Hills The Rolling Hills prospect represents a typical Rocky Mountain coal deposit. Enough geological interpretation has been done to show a complex system of block faulting with coal seams following synclines of stratified lithologies. With the completion of initial drill hole exploration, questions arose concerning coal volumes and strip ratios involved with various pit limits. Quality information had been gathered on the coal intercepts. It was decided that coal vol¬umes and pit designs were of prime importance. The objective was to enter and display data, create a computer model based on interpretation, develop pit designs, compute seam/ waste volumes, and report various contents. The project, begun by entering data in the GEOSEM system, was completed in several days. Data Entry For modeling, the prime information was seam identity and drill hole intercept. Other information-rock type, Btu rating, and percent of ash, sulfur, and moisture-was also available. It, too, was entered into the data base through the computer keyboard and then reported, verified, and corrected. Various reports can be produced, according to user specified sort parameters. For example, from an analysis of available data, only 14 intercepts could be found with Btu value greater than 8000 and sulfur content less than 0.4%. The sort option can also be used prior to entry into the analysis routines. Data Analysis Though the objective was to create a seam model and compute reserves, it became necessary to project quality information into unsampled areas. Statistical analysis was then war-ranted. A typical analysis correlated the lack of relationship between percentage of ash and Btu. Although histograms were also produced, these typified a lack of samples and "ragged" distributions. A geostatistical analysis was also applied, showing the results of computing a 2-D variogram on the largest coal seam. Results showed an average range of 18 m, with a poorly defined variogram. Data Display and Drafting Scaled plans and sections were required so seam locations could be compared to hand drawn interpretations and drill coordinates verified. At the same time, topography could be interpolated from collar elevations to determine whether surface control points were needed for better definition. In addition, a new set of 50 final-scale drawings were required, showing new drilling information. By using the computer screen as a "scratch pad" device, various sections were displayed and then plotted on a drum plotter at the desired scale for overlay on original sections. Both lithology and seam name were plotted for the five main sections. Since the coal seams were striking north-south, sec-

Jan 11, 1981

By Hasan Sevim

This paper summarizes recent developments in modeling of underground coal slurry haulage networks for determination of optimum design and operating parameters. The model presented here is based on a stochastic dynamic programming formulation, applicable in any typical room-and-pillar and/or longwall mining configuration commonly practiced in the United States. The formulation and the structure of the model is general enough to handle design problems involving more than one face and mining method. Given the stochastic operating characteristics and a system layout, the model can be used to determine the equipment configuration and operating regimes that minimize the overall unit cost of coal haulage.

Jan 1, 1983

By R. F. Merwin

Advancement in automation intensifies the need to remove tramp iron from bulk materials being processed and carried on belt conveyors. Although magnets have long been employed for this purpose, it becomes increasingly necessary that magnetic equipment of appropriate types and sizes be selected and advantageously installed -- if maximum benefits are to be derived Tramp iron present in bulk materials consists of ferrous trash, such as wire, bolts, nails, equipment parts, tools, and machine cuttings. The results, if the iron is not removed, are damaging to equipment having close clearances, explosions, or fire, En the case of flammable materials, production downtime losses, and contaminated products.

Jan 1, 1966

By Syd S. Peng

Is the laboratory sized coal specimen much stronger than underground coal pillars? The answer to this question has a profound implication to many coal operators. It will decide how much of the coal reserve can be recovered. Or, in many cases, it will determine whether it can be mined economically. Recent trends in several eastern states to establish regulations regarding coal pillar design to prevent surface subsidence long after mining heighten the debates. And, in some cases, these trends highlight the existing practices that seriously question the conventional wisdom. Currently, nearly all researchers and practitioners agree that as the size of rock specimens increases, its strength decreases. This concept has been universally adopted as the basic principle for coal pillar design in the United States. Several formulas have been derived to account for this effect. The reduction factor for underground coal pillars ranges from one-half to one-sixth of the strength obtained in the laboratory, depending on the formula selected. Recent case studies indicate that the reduction factor is not justifiable, at east in some cases. The use of a reduction factor is based on the assumption hat smaller rock specimens as tested in he laboratory contain none or fewer fractures or planes of weakness than larger specimens or underground coal pillars. In other words, the larger the rock materials, the more fractures it contains and subsequently weaker in strength. Do all underground coal pillars have more fractures than laboratory sized coal specimens? Not necessarily. All coal contains cleats. Some are con¬spicuous but others are not. In terms of cleat density (number of cleats per unit area), there is no difference between an underground coal pillar and a laboratory sized specimen, provided the specimen size is larger than the cleat spacing, which is mostly 25 to 75 mm (1 to 3 in.).

Jan 1, 1993

By Brendan Demich, Joseph McGuire, Emily J. Haas

Near misses recorded and reported by workers can provide awarenessto the potential causes of injury and prompt safety management initiatives. Although most companies require near-miss reporting, it is unclear what the value of these reports are, if any, and how they influence subsequent actions or controls to reduce on-the-job risks. Researchers at the National Institute for Occupational Safety and Health (NIOSH) conducted a case study with an aggregates company in which near-miss reports were analyzed at each of their locations over an entire quarter during the summer of 2018. Within that quarter, workers recorded 249 near misses. Of those, 167 were valid near misses that occurred at work. Researchers coded the reports using a qualitative 5 × 5 risk matrix. Of the 167 near misses, 19% were deemed low risk, 25% moderate risk, 30% high risk, and 26% critical risk. Several patterns in the near-miss incidents were documented, including classification of incidents and common corrective actions referenced (i.e., elimination/substitution, engineering control or redesign, work process/procedures, and personal protective equipment). The analysis provides insight into ways that risk communication and management programs can be improved to reengage workers and their situational awareness on the job.

By Mahmood B. Mirza

The geology of the Gulf Coast Salt domes has been extensively studied by Kupfer (1,2,3,4,5), Atwater (6,7), Balk (81, Hawkins (9), and Wharton (10). dominant geological feature of Southern Louisiana is the Gulf Coast Geosyncline. The axis of this geosyncline corresponds with the present day coastline of Texas, Louisiana, Mississippi, Alabama and Florida. This geosyncline has been continually subsiding since Cretaceous times and receiving large deltaic accumulations of sediments from Central North America. These accumulations progressively thicken toward the South. In the vicinity of the Coast, these sediments are reported to be about 40,000 feet thick. Another dominant feature of the region is the large number of salt domes scattered along the Gulf Coast (fig. 1). Typically, these domes are roughly cylindrical in shape, 1 to 5 miles in diameter, and extend to more than 20,000 feet in depth. It is hypothesized that these domes are derived from the thick Louann salt formation lying below the deltaic sediments. Due to its low specific gravity and buoyancy, the salt layer protruded upwards plastically and pierced the overlying strata. As a result of this upward flow, the adjacent strata are locally lifted upwards, creating excellent traps for petroleum accumulation.

Jan 1, 1979