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By William Gleason

"With desert temperatures climbing high at Caterpillar’s Tinaja Hills Demonstration and Learning Center near Tucson, AZ in September, a group of editors were given a reprieve from the sun and stepped inside the new Cat Minestar Command Center. The movie theater-like temperatures inside were a welcome relief, and the computer screens stationed around the room were an indication of not just how much things have evolved in the mining equipment sector, but also a peek into the future of where mining is headed.Equipment manufacturers like Caterpillar have always had to deal with peaks and valleys in demand that come with mining, perhaps never more so than in the last five years. Sudhanshu Singh, global product manager for Caterpillar, said that in one month in 2012, at the height of the mining Super Cycle, Caterpillar produced more than 150 large mining trucks (haul trucks that carry 136 t/150 st or more). By contrast, Caterpillar produced about 80 of those trucks in the full year of 2016. Between 2012 and 2016, Caterpillar saw its profits drop by 40 percent.“This shows how cyclical the industry is, and it is a testament to the strength of Caterpillar to be able to tolerate the wide swings,” said Singh. Demand for commodities is once again on the rise as are commodity prices with many signs pointing toward a recovery for the mining sector, and Caterpillar has positioned itself for the recovery. During its 2017 press event in September, company officials emphasized that Caterpillar has added strength in its technology divisions by forming new partnerships and adjusting its operating plan.“At the heart of our enterprise strategy is the operating & execution (O&E) model, a strategic framework to identify areas of the business that either create or consume the most value,” said Caterpillar chief executive officer, Jim Umpleby. “Using the O&E model as a guide, we gain a deeper understanding of where we have a competitive advantage, which is key to generating high returns.”"

Jan 11, 2017

By Terry McNulty

There are many potential pitfalls in the commercialization of innovative technology. The failures often are remembered longer than the successes, thereby serving as deterrents to subsequent attempts. The mineral industry's future depends on effective innovation. So it is essential that the causes of failure are understood. Innovation can be examined equally well in the context of geophysics, geology or mining. However the author's experience has been in mineral processing and chemical engineering. So the following discussion is limited to processes and/or plants for producing mineral concentrates, metals or inorganic chemicals. More of what follows has to do with underachievement or failure than success. But this article demonstrates that there is a strong element of predictability in the former. Furthermore, it is a credit to the minerals industry and to the engineering profession that a very high percentage of projects succeed in achieving design capacity and forecast operating costs. Innovation means the introduction of something new. In this article, the words "innovative technology" are used broadly. They include new processes and novel combinations of established unit operations, as well as novel types of processing equipment or largest-ever equipment models. The discussion of project outcomes is based on personal experience or on published information. Citations are given for technical publications that provide either project information or insights into the methodology used to analyze project performance. However, specific projects have not been identified due to the rather negative connotations of some of the conclusions drawn about the less favorable outcomes.

Jan 1, 1998

Conventional wisdom in the mineral processing industry leads one to believe that pressure oxidation of refractory carbonaceous (preg-robbing) ores is not a practical approach to process development. Initial acid pressure oxidation testing on carbonaceous sulfide ores at the Twin Creeks Mine supported this conventional wisdom. After testing other refractory process options, including air and oxygen enriched roasting, Santa Fe Pacific Gold decided to take a second look at pressure oxidation, using conditions outside the normal range of conventional practice. A combination of very fine grinding and high operating temperature and pressure resulted in significant increases in gold extraction. This paper details the effect of operating parameters developed for Twin Creeks on gold recovery, sulfur oxidation, carbon oxidation/passivation and preg-robb through the laboratory and pilot plant investigations.

Jan 1, 1995

By C. R. Montgomery

Coal companies in order to supply their customers En the metallurgical market, both home and abroad, must be able to control their production in order to meet carbonization specifications over and above those of the proximate analyses which has been the prime consideration of purchases in the past. It is the purpose of this paper to review in brief some of the tests used and give data to show the application of such as it applies to the customers needs. It is now recognized that coal is not homogeneous in any of its properties and an amazing fact is that it has been used for so long a time as the principal raw material for the manufacturing of coke without more emphasis having been placed on the variation between coals; yes, even from coals in the same seam at different geographical locations, Recently Kuchta and Clendenin pointed this fact out In a study of the(1) carbonizing behavior as related to chemical and plastic properties of Alabama medium volatile coal.

Jan 1, 1962

By Lawrence S. O’Rourke

Pricing for tantalum raw materials experienced explosive increases in the period 1978-1979, and-similar declines over 1980-1982. The causes for this are examined. Negative effects on the industry are highlighted. Analysis is provided of subsequent structural changes within the industry which minimize probability of future pricing excursions. Data on markets, sources of material, and outlines of concentration and extractive processes are reviewed. The conclusion is reached that expanded sources, future flat demand, and a broader international base of industry participants are principal forces in this restructure. Flat demand is reviewed as a function of increasing application of tantalum, but in more cost effective forms. This is driven by technical advance, notably in electronics applications.

Jan 1, 1986

By K. Verghese

Neutron capture prompt gamma-ray analysis provides the best method for on-line analysis of the elemental composition of large volumes of bulk material. This paper summarizes the Monte Carlo models which simulate the radiation transport within two such analyzer systems; namely, the borehole configuration and the conveyor belt configuration. The models are useful in the design optimization of the analyzer systems, in minimizing the amount of experimental calibration data for calibrating these analyzers, and in investigating the detection sensitivity for different elements. The computational scheme in these models is made extremely efficient by the use of various powerful variance reduction methods and by efficient data management. Experimental verifications of the two models carried out in the laboratory indicate very good agreement with the Monte Carlo results.

Jan 1, 1984

By V. McLemore

New Mexico ranks 2nd in uranium reserves in the U. S., which amounts to 15 million tons ore at 0.277% U3O8 (84 million lbs U3O8) at $30/lb (EIA, 2006). The most important deposit in the state is sandstone within the Morrison Formation (Jurassic) in the Grants district. More than 340 million pounds of U3O8 have been produced from these deposits from 1948-2002, accounting for 97% of the total production in New Mexico and more than 30% of the total production in the United States. Sandstone uranium deposits are defined as epigenetic concentrations of uranium in fluvial, lacustrine, and deltaic sandstones. Three types of sandstone uranium deposits are recognized: tabular (primary, trend, blanket, black-band), roll-front (redistributed, post-fault, secondary), and fault-related (redistributed, stack, post-fault). Several companies are planning to mine these deposits by in-situ leaching.

Jan 1, 2007

By D. Brabec

One of the analytical problems in exploration geochemistry is the choice of a method of sample attack which would be rapid, simple and reliable in terms of precision and discrimination between different concentration levels of elements sought. The wet sample attacks currently used in analysis of silicate rocks vary from total decomposition to leaching by weak extractants. The total decomposition of such materials is usually achieved either by alkaline fusion or hydrofluoric acid attack. The first method requires the use of platinum vessels which is both expensive and slow for batch operation. The second type of attack is more widely applied in rock geochemistry1, but it is still relatively slow for exploration purposes and requires extra care (especially when hydrofluoric acid is used in mixture with perchloric acid). Considerable improvement in speed can be achieved by using the sample attacks which release only part of the metal present in a rock.2,4 One of such attacks is the leaching of pulverized rocks by hot aqua regia.3 Another technique widely used in geochemical prospecting involves fusion of the samples with potassium pyrosulfate (or bisulfate) followed by an acid leach of the malt .5 One of the advantages of these techniques is the use of glassware in decomposition stage which considerably increases the analytical productivity. It should be noted that partial chemical attacks tend to extract from a rock mainly the non-silicate metal which may give results more significant for exploration purposes than the analysis for total metal.

Jan 1, 1970

By Felicia F. Peng

To minimize SO2 emission and the particulate problem during combustion of high sulfur coal fines is to agglomerate these fines in the presence of limestone. At subsequent combustion process, the sulfur in coal is oxidized and reacts with calcined limestone to form calcium sulfate in ash, while the base carbon is converted to clean energy. Seventy percent of sulfur retention can be achieved at Ca/S mole ratio of 3 at a temperature range of 500-400°C. The sulfur fixation in agglomerates involves the complex mass transfer and multiple successive reactions. The rate expressions have been developed to describe the progress of sulfur fixation in the agglomerates during combustion.

Jan 1, 1985

By F. Ansheng

Though it becomes increasingly important with the valuable minerals in their deposits tending to be fine and poor, the solid and liquid separation remains difficult especially when the particles are of micrometer size and of low density. Almost of all conventional thickeners result in that fine particles lose into overflows which often costitutes a loss of potentially valuable resources as well as an environmental hazard. The addition of flocculations may improve the settling of solids but may also not work well for the final removal of fine particles from the overflows (Ref.1).

Jan 1, 1990

By Martha E. Smith

INTRODUCTION Radiation is one of the many agents occurring in our environment that is capable of causing cancers. We are all unavoidably exposed to natural background radiation. If we wish to exploit the beneficial uses of radiation in medicine, industry, and for the production of electricity, some further exposures to radiation are almost inevitable. One needs to ensure therefore, that the standards of radiation protection are safely derived and one would want to understand the mechanism by which radiation might cause cancer and genetic defects. In order to study the effects of radiation one can: (1) analyze human data, (2) perform animal experiments, and (3) do molecular level experiments. Indeed all three kinds of information are needed. This paper will concentrate on the steps required to obtain some of the necessary human data regarding health effects, where the concern is about the impact and consequences of long-term low-level exposures to an agent. Such investigations require some knowledge of work histories, dose histories, health "outcomes", and the personal identification of the individual involved. Three inter-related computer systems have been developed at Statistics Canada which have been designed to permit optimal use of a number of different records for our entire country for such health related research. The development of the Canadian Mortality Data Base, the initiation of the National Cancer Incidence Reporting System, and the development of new computer linkage techniques have helped reduce the cost and increase the scale and efficiency of automated follow-up to produce statistics of sickness or death associated with radiation and other carcinogenic agents in mines. These computer systems have already been implemented, and references will be made to studies currently being conducted using these files and facilities (e.g. a study of all Ontario miners, plus various Canadian uranium, fluorospar, salt and nickel miners). We will also look at the kinds of data that need to be collected now, to improve such studies in the future. DELAYED RISKS - THE STUDY SIZE AND COST Delayed effects on human health, as for example industrially caused cancer, can in general only be detected and measured by following-up the individuals to see what eventually becomes of them. What is not generally recognized is that the relatively low levels of individual risk, about which the public is often concerned, usually requires for their detection that very large numbers of "exposed" and "control" individuals (e.g. 10,000 to 100,000 or more) be followed over a period of two or three decades to determine when they die, what they die of, and whether they contracted cancer or some other disease of special concern. Thus, it is frequently exceedingly difficult to make such investigations cost-effective so that they will be undertaken at all, and as a result very real risks to health can remain undetected or unquantified. THE MANUAL PROCEDURES Follow-up of individuals by epidemiologists has until recently been a largely manual and clerical operation. It has used a diversity of source record files; local, regional, and national. Often the tracing of people has involved letters sent through the mails and visits to institutions, physicians, municipal offices, and former neighbours. Only thus could one find out whether the individuals were dead or alive. Such studies were necessarily small, or else very expensive. Death registrations have, by tradition, provided a valuable tool for the identification of harmful influences in the environment. However, with the increasing mobility in the population, death may often occur far away from the place of exposure to such an influence. Thus, no longer will simple manual searches in a single registry office suffice to inform the investigator concerning the deaths that may have occurred in a study population, especially when that population is large. In the past, manual follow-up to locate the relevant death registration normally required some prior knowledge of the province and year of death in question, so that the alphabetic indexes could he used to direct researchers to the appropriate bound volumes of registration forms. To search manually in this fashion for any large number of death registrations, without knowing in which year or province the deaths had taken place, or even whether they had yet occurred, would be impractical, since each year in Canada there are about 170,000 deaths. DEATH AND CANCER AS SPECIAL ENDPOINTS Much of recent effort has been focused on the organization of the "endpoint" files required to do long-term follow-up studies on a national scale, because that is a function which other institutions are unable to perform due to the confidentiality laws governing the use of such information. Outside organizations generally come to us with detailed "starting" point records which relate to some specific group requiring study. We carry out these epidemiological searches on a cost-recovery basis. The analytical interpretation of results is normally

Jan 1, 1981

By Harry Teicher

The subject of Specialty Silica Products could encompass a broad range of materials, some of which would be familiar to members of the Society of Mining Engineers. With the concurrence of your chairman, I have chosen to limit my remarks to synthetic materials, not including such siliceous materials as diatomaceous earth, asbestos, quartz and clays. For purposes of discussion, I have classified Specialty Silica Products into two groups -- powders and liquids -- which I will discuss in that order and which are categorized in Figure 1. The synthetic silica powders are amorphous to x-rays and are manufactured by various processes resulting in products of a wide range of physical and chemical properties, as well as functional performance and applications. Applications or functional properties are generally dependent upon such physical properties as micron-sized particles exhibiting large surface areas per unit weight and low apparent bulk density. Their presence in various systems modify surface properties. As summarized in Figure 2, they act as viscosity modifiers, flow conditioning agents, anti-slip agents, anti-blocking agents, flatting agents in surface coatings, reinforcing agents in polymers such as silicone rubber and numerous other applications. Although the various types of silicas exhibit various levels of functional performance in these end uses, they are not usually equally effective as direct replacements and I will briefly discuss the various types of materials.

Jan 1, 1974

By Kyle Kittle, Kyle Knaeble, Albert Ruiz, Gregory Raines, Ryan Gewargis

The Chimney Hollow Reservoir Project (CHRP) is located southwest of Loveland, Colorado. CHRP is a component of the Windy Gap Firming Project, operated by the Municipal Subdistrict of the Northern Colorado Water Conservancy District. The inlet/outlet tunnel (IOT) for CHRP contains a reinforced concrete lined alve Chamber with PC membrane waterproong that was ecavated via seuential ecavation method to a diameter of feet. The IOT was ecavated using both drill and blast and road header with ground support consisting of steel sets, rock bolts, wire mesh and shotcrete. The IOT will withstand 300 feet of water head and rock ll surcharge load from the dam embankment constructed over the tunnel.

Jun 23, 2024

By George I. Staber

As stated by the Congress in the preamble of the act establishing the Office of Coal Research, its purpose is, "To encourage and stimulate the production and conservation of coal in the United States through research and development by authorizing the Secretary of the Interior to contract for coal research, and for other: purposes." Thus, while the overall responsibility for air pollution control from all sources rests primarily with the Department of Health, Education and Welfare, it is obvious that OCR could not perform its mandate of, increasing the utilization of our Nation's greatest energy resource if it ignored one of the greatest practical obstacles to achieving that objective. Therefore, air pollution abatement and prevention is one of the practical considerations taken into account in the selection of the OCR program. And as the severity of the air pollution problem imposes new restrictions on the use of coal, the importance of this criteria in the selection of OCR projects increases. The work done by OCR in air pollution abatement does not conflict with nor does it duplicate the program developed by HEW's National Center for Air Pollution Control. Technical members of the OCR staff maintain close formal and informal liaison with their counterparts in NCAPC. One formal agreement has been executed whereby the HEW agency has transferred funds to OCR for a practical study of the potential effectiveness of air pollution control when coal is burned in a fluidized bed comprised of inert alkaline earth material. It is hoped that this initial cooperative effort will be

Jan 1, 1968

Improvements in computer technology and associated software have allowed the improvement and development of more advanced ventilation modeling software packages including those that have the ability to simulate the effects of a mine fire on the ventilation system in terms of heat, smoke and gas distribution. This ability has real applications for the mining industry in terms of emergency planning, training and response. The primary focus of this paper will be the benefits to training programs that this type of software can provide to all types of training for various personnel, from the newly hired inexperienced miner, mine rescue, atmospheric monitoring personnel and emergency evacuation drills. The results of the simulations can then be used to give miner?s more detailed information on what types of conditions they may face based on the type and location of the fire and the program itself can be used to manipulate the ventilation system in a way that emergency response personnel may (i.e. tear down stoppings to reduce airflow to the fire area) and see the effects in real-time.

Jan 1, 2012

By Jürgen Brune

This is a shortened version of the paper ?The Methane-Air Explosion Hazard Within Coal Mine Gobs published in the 2013 volume of SME Transactions (Brune, 2013, pp. 376-390). This paper analyzes the explosion hazard resulting from the formation of methane-air mixtures in the mined-out gobs of underground longwall coal mines. Evidence from numerous mine explosions suggests that explosive methane zones can form within longwall gobs. Explosions and fires resulting from these methane accumulations have led to severe and fatal injuries to the miners, including the explosion of the Upper Big Branch Mine in West Virginia, where 29 miners lost their lives April 5, 2010.The paper also reviews current research on numerical modeling of gas flows in longwall gobs and outlines how targeted injection of nitrogen into gobs can effectively reduce the volume of such explosive methane zones. The paper concludes that comprehensive monitoring of gas compositions, along the accessible fringes of the gobs along with inertization, improved ventilation schemes and further research are necessary to control this explosion hazard and make mining operations safe. Keywords: Longwall, gob, methane, EGZ, explosive gas zones, underground, coal, explosion, fire

Feb 1, 2014

By Thomas R. Hightower

The Thunderbird plant was erected in Sullivan County in Indiana during 1958-1959. It was first put in operation in March of 1959. At the present time the source of the raw coal is from the Indiana No. 6 seam. The underground operation at present consists of two continuous mining units and two conventional units. The underground is all belt haulage and the first unit with which this paper is concerned is the slope belt. It is a 48-inch-wide inclined belt with 980-foot centers and a lift of 275 feet. The belt is powered with a 350 H, P, motor and has a rated capacity of 600 Tons per Hour. The belt is equipped with a Merrick Scale Company Weightometer, The raw coal moves from the belt to a 6'x12' extra heavy Allis-Chalmers Ripl-Flo equipped with 6" round-hole screens. The over product of the screen is fed into a 10'x20' long McNally- Pittsburg rotary breaker equipped with 4-l/2" round-hole screens. The oversize rock is discharged into a bin that is emptied with a refuse truck. The through-product of the breaker, along with the through-product of the Ripl-Flo, passes either directly to the McNally Giant washbox or to a 36" belt that transports it to a 1000-ton storage bin,' The change from either to the washbox or to the storage bin is made by use of a motorized gate controlled by the plant operator,

Jan 1, 1961

By James M. Barker

Marketing is the linchpin of the industrial-mineral (IM) industry. Without markets and consumers for IM products, all other associated IM activities are superfluous. The simple existence of an IM deposit does not mean that it can be exploited. A dynamic interaction between exploration (geology), mining, processing, transport, marketing, sales, and consumers is required for profits. Geology dictates the existence of a deposit, but markets dictate its development, and transportation provides the connection. This is true to such an extent that marketing commonly is called the exploration phase of IMs. Marketing is strategic and includes long-range market-development and planning activities, whereas selling is tactical and more focused on day-to-day consumer interactions. Each will help the other when properly done. Many producers of IMs have failed because of inadequate marketing skill, information, and practice. Over many years at the Montana Bureau of Mines, the many developers seeking technical assistance to find an IM deposit, but who had no marketing plan, always failed. In contrast, the few who sought assistance first on marketing, with the IM deposit to be found later, always succeeded (Richard Berg, personal communication, 1998). Marketing has many facets helped by geologists who must be aware of what marketing is attempting to do. A geologist needs to understand many aspects of IMs: location (deposits, plants, consumers), processing (specifications), transportation (truck, rail, barge, ship), competition (local, regional, national, international), substitutes, pricing, and new developments and market forces of all kinds. Some needed skills are not taught formally to geologists, so well-rounded self-education and on-the-job training are the way a geologist normally enters into IM marketing. The IM geologist generally is associated with marketing either by helping to prepare a market study or by acting on the results of one. Preparing a market study is a two-part process. The first part is relatively simple but requires a time-consuming collation of data into an IM survey (mostly past-and present-oriented). The more difficult and much more important second part entails expanding the IM survey into a market evaluation (mainly future-oriented) that emphasizes forecasting, timing, location, and specific products. A market evaluation generally boils down to formulating the right questions to ask of the right persons. One very good question to ask is, "What could be the market for this specific IM?" while thinking for yourself without excessive recourse to gossip, rumors, promoters, developers, or (at times) IM experts. The evaluation must prove that market potential exists and suggests a marketing plan. Effective marketing is an ongoing process, with the initial marketing plan modified over time, using wide and continuous input to avoid tunnel vision. Industrial-mineral markets are based either on commodity (lower-priced, basic-processing) minerals or specialty (higher-priced, value-added) minerals. IM marketing methods are either product-driven (commodity minerals), a more traditional approach, or market-driven (specialty minerals), but these are neither mutually exclusive nor is one always better than the other. Focusing too much on specialty minerals can lead to problems. A blend of commodity products with specialty products commonly lowers risk and enhances long-term profits. The highest profits occur in specialty minerals at the cost of higher risk and complexity and require intelligent marketing, versatile technical services, and creative research and development. Industrial minerals are best served by an industrial-marketing approach rather than a consumer approach. Modern industrial marketing emphasizes the consumer using the "marketing concept." The marketing concept focuses all management and operational activities on total consumer management and satisfaction similar to the total quality management approaches to excellence.

Jan 1, 1999

By Dermot M. Ross-Brown

The more important factors controlling the design of pit slopes are related to the local geology over which the designer has little or no control. Nevertheless, there are some factors over which the designer does exert some control and these concern the say in which the rock is excavated and supported. They include blasting, face cleaning, water control, and the use of rock improvement techniques. The paper discusses these factors and relates the extra costs incurred to the steeper slope angles that can usually be obtained. It is demonstrated that even a modest increase in bench angle of 5° through improved excavation techniques can pay off in a single push-back.

Jan 1, 1975

By R. N. Torbin

The degree to which automation, remote control and robotics have been used in the mining industry is far less compared to general industry. Reasons include the adverse working environment, the difficult work operations and the generally lower incentive for capital investments in new mining equipment. The author and his employer has been involved in the development of advanced mining and underground construction equipment. This equipment is designed to he remotely operated, to improve both productivity and worker safety. Many of these machines employ advanced electronics and robotic features. The types of machines that will be discussed include remote shaft lining and placement, remote excavation and mining operations, and automated conveyor systems.

Jan 1, 1991