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By Andrew McGrath, Geraldine Lyons, Sarah Barcelona

In the dynamic and challenging modern industry landscape, understanding and unleashing the true role and contribution of technical teams is crucial to business success. The cyclical nature of industries has led to shifts in the technical professional’s place within the organization and the technical skills that are desired most. This paper reframes the pivotal role that technical professionals play within complex operating assets to maximize value and realize full potential. This investigation focuses on the Rio Tinto Kennecott Technical group’s cultural journey, which is underpinned by an investment in its people. The conflict between legacy industry beliefs and the necessity for cultural change emerges. This is illustrated by a deep dive into the evolving case study of Kennecott’s Bingham Canyon Open Pit Mine Technical team. Here, a multi-faceted approach to cultural change is helping to unlock the team’s contribution to the life extension of an aging asset. Guided by a vision and strategic roadmap, this approach is part way through a 5-year implementation period and is yielding encouraging business outcomes.

Feb 1, 2024

By H. B. Miller

By its nature, underground metal mining is unlike any other business in the industrial sector. Operations are continuously exposed to economic risk as a normal consequence of mining due to uncertainties associated with the? deposit, excavation, and ever changing political, regulatory, and market conditions. Out pacing advances in productivity and technology, these conditions have contributed to the steady decline of underground hardrock mining in the United States. This paper investigates the trends and major factors believed to be responsible for this decline. Special consideration is given to changes in direct operating costs, labor productivity, and production capacity.

Jan 1, 1995

By Chinmay Shingote, Robert Visintainer, Renjie Ke, Jaikrishnan R. Kadambi, John Furlan

Hydrocyclone separators are some of the most widely used instruments in a variety of industrial applications. Their major functions are to sort, classify and separate solid particles and liquid droplets within a multiphase flow system. Research studies employing both experimental and numerical methods recognize that the performance of a cyclone is related to its geometric dimensions as well as the inner flow pattern. Although many successes have been achieved over the past years, the majority of investigations only focused on the simplified design of cyclone geometry and on single-phase flow. Therefore, this study set out to investigate the flow field in a new-design hydrocyclone and used particle image velocimetry (PIV) to explore the complex swirling flow behavior inside the cyclone within an air core. The flow field inside the cyclone was also studied by computational fluid dynamics (CFD) simulation using a commercial CFD package. Different turbulent models were tested in this study with a moderate-size mesh, and the interface of liquid phase and air phase was predicted by the volume of fluid (VOF) model.

By Ashutosh Kumar Bharati, Rajesh Rai, B. K. Shrivastva, Arunava Ray

Opencast mining method is one of the most productive mining methods available at present, which is generally associated with the removal and handling of a huge amount of overburden material. Hence it imposes a serious challenge of dump slope stability and that too, mainly in the case of internal dumps. The study is primarily focused on the stability of dragline dumps and the subsequent development of a rating system to classify the stability of dragline dump profiles. Initially, numerical simulation is executed through RS2 (Version 9.0) software, which is based on the finite element method. Thereafter, simulation results are used to perform the sensitivity analysis of various geometrical and strength parameters of the dump slope, and the two-factor interaction method is also incorporated into the analysis, this method included the dependency of closest parameters while calculating the sensitivity index, and thereafter, it is converted into the rating of each parameter. The strength parameter like the angle of friction and the geometrical parameter like slope angle of the bench between the coal-rib roof and dragline sitting level are assigned the highest rating value. Based on the overall rating of the dragline dump, the dump slopes are classified into various classes, viz., very safe, safe, vulnerable, unstable, and highly unstable. This classification proved to be handy in the quick estimation of the stability of the dragline dump and also gives an idea of designing optimum and safe dragline dump profiles. The developed classification chart has been validated by the previous research works and has found similar results.

Feb 15, 2021

By Gennaro G. Marino

This paper summarizes and evaluates data on mine subsidence ground movements and associated damage for houses in Illinois. Based on the data collected, the response of homes to subsidence ground movements is expressed in terms of repair costs. A damage criteria is then proposed that relates the ground movements and damage levels. The data were collected as part of a comprehen¬sive study performed for the Illinois Abandoned ?Lined Lands Reclamation Council, A -M-RC, by the Civil Engineering Department at the University of Illinois, and probably will be published in late 1934 by the council. The study concentrated its efforts on surface ground movements and the effects to houses over abandoned room and pillar mines. The resultant surface subsidences are commonly dish or bowl shaped and are termed sags. Method of Analysis The steps in analysis used to arrive at the proposed damage criteria are: 1. Canvas and rap subsidence damage in houses, 2. Assess the associated ground movements, 3. Estimate the damage repair cost, 4. Develop a damage/repair level classifica¬tion, 5. Correlate the associated ground movement, damage/repair level and home construction type, 6. Propose a damage criteria.

Jan 1, 1984

By R. W. Waytulonis

New exhaust control techniques and devices may be necessary to meet future diesel particulate matter emission standards in underground coal mines. This paper reviews conventional work practices and devices used to control diesel exhaust emissions, and new techniques being tested by the Bureau of Mines. Discussions will center on important work practices and on the function and efficiency of exhaust after-treatment devices. An industry/government cooperative research project to develop and test an exhaust after-treatment system for part 36 equipment is also discussed.

Jan 1, 1990

By William H. Dresher

The crust of the earth, together with its seas and its atmosphere, is the source of all of mankind's primary wealth. Indeed, most people think of precious metals and stones when they think of wealth mined from the earth, but the value of the material and energy goods derived from the earth far exceed the value of the precious metals and gem stones. Thus, it is obvious that all minerals which we mine from the ground represent new wealth--the copper, clay, or petroleum we mine just as much as the gold or silver. More and more, wealth is defined in terms of utility-not in terms of an arbitrarily established monetary value. The recent action of the OPEC nations in controlling the flow of petroleum has clearly demonstrated this to the petroleum-importing nations! There is developing in the United States, as well as in many other nations of the world, a concern for the future availability of many mineral-derived raw materials and of mineral fuels. Ore grades are diminishing, concern for the environment has placed restraints on commercial development of some mineral deposits and the processing facilities necessary to exploit them, and countries upon which we have relied for major mineral materials have become increasingly nationalistic, causing uncertainties in future supply and causing an increasingly alarming deficit in our nation's balance in trade.

Jan 1, 1980

By J. E. Feddock

To succeed in today's competitive coal market, coal companies must continuously improve production and lower cost. However, the coal industry's historical management practices must change to remain viable? The practices of the current day efficient coal mine manager are reviewed and examined using W. Edwards Deming's definition of management. The statistical tools, including Pareto Charts, Control Charts and Scatter Diagrams, which identify the problems management must approach differently to increase productivity at a coal mine, are discussed.

Jan 1, 1993

By Bryan Ulrich

Knight Piésold and Co. hosted its annual roundtable discussion on March 17, 2011 at the Stockman Hotel and Casino in Elko, NV. The theme for Roundtable 2011 was, ?High density tailings, paste, and filtered tailings,? although the topic may well have been subtitled, ?Don?t prematurely rule out any technologies before they are given their day in court.? Bryan Ulrich, Knight Piésold?s local representative, as well as Tom Kerr from Knight Piésold?s office in Denver, CO, were on hand to help facilitate the discussion. Ulrich and Kerr are senior vice president and president of Knight Piésold?s U.S. practice, respectively. The event played host to more than 30 attendees from several western states. Attendees included personnel from a dozen mining properties and various corporate offices. There were also attendees from manufacturing and specialist consulting firms who have been providing services to various high-density tailings, paste and filtered tailings operations worldwide. It may be noted that the term ?filtered tailings? is used in this discussion. Alternative terms, such as ?dry stack? or ?dewatered tailings,? should be avoided whenever possible, as such terms tend to give a false sense about the nature of the material since these materials typically still retain a significant amount of moisture.

Jan 1, 2011

By J. R. Hoskins

Method - A direct approach to instrument users, initially by letter and later by telephone or personal contact was made. The resultant data was compiled to give specific use information on the seven instruments. During the course of the study attempts to evaluate the Griswold Gage were abandoned when it became apparent that the gage was not being commercially produced. One company is developing the gage for its own use. The information presented is the result of over 1200 inquiries.

Jan 1, 1973

By Lianhui Jia, Yali Han

"The key technologies of a large rectangular pipe jacking machine with dimensions of 10.12m × 7.27m (width x height) include selection of rectangular cross-section cutting modes, analysis on the strength and stiffness of the rectangular shield, integrated control of electro-hydraulic proportional thrust systems and ground conditioning for excavation are presented in detail in this paper. These key technologies have been successfully applied and verified on site during tunneling, providing a new concept for the building of large rectangular traffic and pedestrian tunnels in urban areas for the future.1 INTRODUCTIONIn the past, underground tunnels were mainly used for drainage, sewage, utilities, metro tunnel, etc. and most of them had circular cross-sections. Recently, as a result of economic development, gradually accelerating urbanization process and diminishing ground space, underground tunnels have already become a new trend for urban underground space utilization. Due to the heavy traffic flow, the demands for rectangular cross-section underground tunnels, such as pedestrian underpass and road tunnel, are increasing gradually.The Rectangular pipe jacking machine (hereinafter referred to as RPJM) was firstly developed in Japan for the construction of metro station, pedestrian underpass, underwater tunnel by-passes, etc. Kazunaki Kawai et al. introduced a RPJM developed and manufactured by KOMATSU in 2002 [1]. Tosikazu Kubota et al. confirmed the rectangular tunnels’ superiority to circular tunnels with regard to larger inner cross-section and lower construction cost in their RPJM construction reports [2]. Compared to circular pipe jacking machines, a RPJM also has the merits of a higher inner tunnel space utilization ratio and is able to excavate in shallow overburden areas. As shown in Figure 1, the effective area of a rectangular tunnel is more than 20% higher than that of an equivalent circular tunnel."

Jan 1, 2016

By Ayokunle Adewale Akinlalu, Sunday Bayode, Sherif Olumide Sanusi, Joshua Oluwagbenga Adeboye

Gold occurrences have been reported in Alagbede, southwestern Nigeria, but a mineral potential map (MPM) to guide academics and investors in the area is still needed. As a result, geophysical methods (aeromagnetics and aero-radiometry) have been used to assess the potential for gold minerals in the area. Several enhancement filters, such as reduction to the equator, upward continuation, analytical signal, second vertical derivative, and power spectrum analysis, were applied to the aeromagnetic data to understand the subsurface geology better. The enhancement filters applied to airborne radiometry data are K/eTh, ternary color composite, F parameter, and deviation from the ideal K values (Kd). Geophysical data analysis was used for structural mapping and geological reconstruction, while aero-radiometric data was used for hydrothermal alteration mapping. The primary trend observed in the area’s magnetically inferred structural framework map is NE-SW, while a few are in the NW–SE and E-W trends. These observed trends show that the study area suffered at least three deformation episodes. Geological evidence of gold mineralization, such as favorable lithology, geological structure, and hydrothermal alterations, has been fused to produce a reliable MPM of the area. The geographical location of the existing mineral sites in the investigated area agrees with the geological structures and the MPM produced there. Thus, the systematic approach adopted in this study can be extended to other supracrustal belts of a typical Precambrian basement complex worldwide to ensure the reliability of orogenic gold mapping and resource management.

May 9, 2023

By S. L. Manske

The Mesquite gold deposit is a recent discovery of Gold Fields Mining Corporation lying 65 kilo- meters northeast of El Centro in Imperial County, California (Figure 1). The deposit is located on the southwestern flank of the Chocolate Mountains and is a bulk-minable, low grade "disseminated" orebody. Although the host rocks of the deposit are part of a regional high-grade metamorphic terrane, abundant brittle fractures, brecciation, and open-space vein fillings indicate that Mesquite mineralization is epithermal. Faulting which postdates the hydrothermal activity has complicated the original geometry of the orebody. Alluvium effectively hides most surface expression of the mineralization, but open-pit mining is now revealing the details of Mesquite geology.

Jan 1, 1987

By Qinbo Cao, Qianshan Peng, Heng Zou, Xingcai Yu

In this work, a new flotation strategy was proposed for the flotation of rutile. In this strategy, rutile was activated by Pb(NO3)2 and then floated with amyl xanthate (AX) as a collector at pH 8. Pb(OH)+ was the dominant lead species in the solution at pH 8 and is believed to be the major species reacting with the rutile surface. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) study revealed that the lead activation products were well distributed on the rutile surface, and AX− could further bind with the Pb atom on the Pb-activated rutile surface. In this regard, the Pb-activated rutile could be floated by AX. Furthermore, X-ray photoelectron spectroscopy (XPS) analysis indicated that Pb(OH)2 was generated on the Pb-activated rutile surface. The electron transfer during the adsorption of the AX− on the Pb-activated rutile surface was also investigated by XPS analysis.

By Jack C. Haptonstall

The Tayoltita Unit of Minas de San Luis, S. A. is situated in an isolated corner of the state of Durango, Mexico. The ore deposits in the region were first worked by Indians, but by 1757 the Spaniards had discovered them, and the first systematic exploitation of the mines commenced. By the early 1900's most of the mines had been acquired by American interests, and the San Luis Mining Company was organized. The modern period of exploitation, uninterrupted for the last 74 years, began. In 1962 the company was fully "Mexicenized" in compliance with the modification of the mining law, and the name was changed to Minas de San Luis, S. A. Tayoltita continues as one of Mexico's most important silver and gold mines. The ore is extracted in en extensive underground operation, mining epithermal fissure veins by selective methods. The ore is milled and treated in an efficient counter-current cyanide plant, where 95 % of the silver and 96 % of the gold is recovered. Current annual bullion output is 55,000 kg (1.7 million troy oz) of silver and 1000 kg (31,000 troy oz) of gold from milling 165,000 try (181,900 stpy). Rough, 33-kg (1000-troy oz) bullion bars are smelted at the mine, shipped by air to Mazatlan, Sinaloa, and are thence sold to the Met- Mex Peñoles smelter in Torreon, Coahuila. Ore reserves, blocked by very conservative methods, are currently at 540,000 tons (595,000 st). Ore reserve grade is 425 g of silver and 6 g of gold per ton (12.4 troy oz Ag and 0.18 troy oz Au per st).

Jan 1, 1976

By M. A. Trevits, A. Ozment

"According to the Office of Surface Mining Reclamation and Enforcement, Abandoned Mine Land Inventory System, in 2013 there were 98 underground mine fires in nine states. This is considered to be an underestimate for the actual number of fires nationwide. Many mine fires are started by people burning trash where the coal seam or an abandoned coal mine is close to the surface. Other fire ignition sources include lightning and forest fires. Once ignited, a coal mine fire can easily spread into the remaining coal pillars and mine entries. Once established, the fire creates its own ventilation system supporting further combustion by drawing air down into the workings through unsealed mine shafts, fractures and surface subsidence depressions. As the coal left in the workings from the past mining operations burns, the mine void can collapse, causing subsidence and creating dangerous voids, damaging overlying surface structures and roadways. The products of combustion include smoke and noxious fumes such as carbon monoxide gas. These products are released to the atmosphere through fractures that develop within the ground surface, killing vegetation and creating serious health hazards (Richmond, 2017).Abandoned mine fires, if left uncontrolled, can burn for years and, in fact, one of the most wellknown mine fires in the United States is the mine fire in the Borough of Centralia, PA, that began on May 27, 1962. Reportedly, officials decided to clean up the local landfill for the upcoming Memorial Day holiday by burning the garbage on the site. Unfortunately, the landfill was located on the site of an abandoned strip-pit mine on the edge of the Borough (Dekok, 2009). The strip pit had been left open after being excavated around 1935 and was approximately 23 m (75 ft) wide and 15 m (50 ft) deep. It is believed that the lack of a properly constructed noncombustible shale barrier in the strip pit enabled the fire to spread to adjacent carbonaceous refuse material and then to nearby coal mine workings (PA DEP, 2017). As time went on, the fire grew and spread under the Borough and directly affected the residents despite various efforts to extinguish the fire by the state and federal governments (Fig.1). In 1984, a voluntary program was begun to move residents from their homes. Many accepted buyout offers for their properties and moved elsewhere and after leaving, their homes were demolished. In 1992, the state used eminent domain to take control of all the property within the Borough. In 2013, after years of litigation, the eight remaining residents were allowed to stay for as long as they lived. Today, only a few buildings remain within the Borough (Centralia, PA, 2014). This fire has been burning for more than 55 years."

Jan 5, 2018

By C. RAMADINI, F. NURJAMAN, A. SHOFI, B. SUHARNO

In this work, the selective reduction of lateritic nickel ore was carried out using sodium sulfate, sodium carbonate, and sodium chloride as additives. The 5 wt% of anthracite coal, which contains 60.35% of fixed carbon and 1.9% of sulfur, was used as a reductant. All raw materials were mixed homogenously prior to the pelletization process into 10–15 mm of diameter. The reduction process was carried out to 50 g of pellets at 950 °C, 1050 °C, and 1150 °C for 60 min in a muffle furnace at atmospheric pressure. It continued with a wet magnetic separation process to separate ferronickel (concentrates) and impurities (tailings). Iron and nickel grade analysis was performed using XRF, while phase transformation and microstructure were analyzed with XRD and SEM–EDS. The results showed that the sodium sulfate was superior, resulting in the highest nickel grade in concentrate, i.e., 15.06%. The sulfidation mechanism, which could inhibit the metallization of iron, effectively increased the nickel grade in concentrate than decomposition of carbonate and chloridization process. The sulfur content in the reductant also influenced the selective reduction process. It promotes more sulfidation of iron, thus increasing the nickel grade in concentrate.

Jul 7, 2021

By Michael J. Shulman

The DEAREX knowledge acquisition and engineering system is a teaching and exploration tool designed to facilitate the under- standing and development of expert systems by explorationists without the aid of a knowledge engineer and without recourse to expert system languages. To fulfill its objective, the DEAREX system considers the selection of exploration methods in desert areas. The system consists of three parts: 1. A tutorial which introduces the basic and selected advanced concepts of expert systems, 2. A sample program illustrating how an expert system works and can be used, and, most importantly, 3. A knowledge acqusition and engineering program which enables users to develop their own expert systems. The tutorial provides a brief and concise introduction to expert systems, a 10 rule exploration example which defines, explains and illustrates the basic concepts and design of expert systems, and a glossary of expert system terms including cross references. The sample program is a larger, self contained example of an expert system with some commentary illustrating addition- al expert system concepts and the role of the knowledge engineer in particularizing rules and ascertaining the knowledge base. Restricting itself to the selection of exploration methods in desert areas, the knowledge acquisition and engineering program questions the user and converts the answers into an expert system. Questions pertain to geology, infrastructure, availability of instrumentation, personnel, etc. Additional information may also included. In conclusion, some salient points concerning knowledge engineering toolkits, shells and knowledge acquisition capabilities such as contained in DEAREX are discussed.

Jan 1, 1992

By N. Hoffman

Accurate, repeatable density measurements of a coal-magnetite-water slurry are difficult to achieve using a nuclear density gauge. Changes in the coal-to-magnetite solids ratio cause fluctuations in the readings of nuclear gauges. To investigate this problem the Electric Power Research Institute's Coal Cleaning Test Facility compared the performance of a nuclear density gauge on a coal-magnetite-water slurry with the performance of a differential pressure gauge modified with a new pressure sensor. A second aim of these preliminary tests was to determine if the differential pressure gauge is also sensitive to the type of solids in the slurry. This paper explains current slurry density measurement practices, describes the nuclear and differential pressure gauges used in the CCTF tests, and presents test methods and results.

Jan 1, 1986

In this paper, we present design and implementation details of a fuzzy-behavior-based controller for an automated excavator. This robotic excavator must be equipped with sensors, actuators and an embedded control system. The excavator controller uses neural-networks to interpret forces and torques gathered from bucket mounted force sensors during the excavation process. Implementation details and experimental results using the fuzzy behavior based excavation controller are given for several excavation tasks. These excavation tasks demonstrate some of the complex skills that are essential for an autonomous mining excavator controller.

Jan 1, 1996