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By Osvaldo A. Bascur

Intelligent systems (IS) technologies have received much attention in a wide range of process engineering applications including process operations. With the revolutionary progress in information and computer technologies applying the latest technologies in metallurgical complexes has become a serious challenge to both management and technical teams. Objects and components are changing the way everyone relates to their computer and networks. Goals of real time performance monitoring includes maximizing the profitability by maximizing production, improving efficiency, attending product quality, costs, maintenance, environmental and safety regulations. Designers must consider the greatly expanded desktop computing, Microsoft object technology, Internet and how to build these systems. This paper discusses some opportunities and challenges using objects, components in designing applications and integrating intelligent systems tools. Two examples using performance equations and IS technologies applied to mineral processing are presented.

Jan 1, 1997

Critical safety tools to locate miners underground are featured by several exhibitors at MINExpo. Communication was the buzzword for health and safety products at the 2008 MINExpo, and it is still important in 2012. Products unveiled following the Miner Act in 2006 have been upgraded and improved. Saving lives and reducing injuries through better leadership, planning and practice is the goal of every mine professional.

Jan 1, 2012

By M. Deutsch, E. González, M. Williams

"Uncertainty exists in ultimate-pit limits due to geologic variation and unpredictable economic landscapes. In this work, we show how this uncertainty affects the ultimate pit and how it can be analyzed to improve the mine planning process. A stochastic framework using geostatistical simulation and parametric analysis was used to model the effects of geologic and economic variations on ultimate-pit limits and overall project economics. This analysis was made possible by a new pit optimization implementation that can be automated and set up to calculate ultimate pits for hundreds of different scenarios in a matter of hours. Quantifying ultimate-pit uncertainty early in the mine planning process allows mining engineers to make informed decisions regarding infrastructure placement and to mitigate the possibility of incurring substantial costs to relocate critical mine facilities. Resumen ¦ Existen dudas sobre los límites del pit final por causa de la variación geológica y lo impredecible de los paisajes económicos. En este trabajo les mostramos como esta incertidumbre afecta el pit final y como puede ser analizada para mejorar el proceso de planificación de la mina. Se usó un marco estocástico con simulación geoestadística de análisis paramétrico con el fin de poder hace la modelación de los efectos de las variaciones geológicas y económicas en los límites de pit finales y proyectos económicos en general. Este análisis fue posible gracias a una nueva implementación de optimización de pits que puede ser automatizada y configurada para calcular pits finales para cientos de escenarios diferentes en cuestión de horas. La cuantificación temprana de la falta de certeza en pits finales durante el proceso de planificación permite a los ingenieros de minas tomar decisiones informadas en lo que respecta a la ubicación de infraestructura y en la mitigación de posibles costos sustanciales por causa de la reubicación de instalaciones clave de la mina."

Jan 1, 2015

Never known as a conference to shy away from its share of off-color jokes, the Colorado Mineral Processing Division?s Annual Meeting returned to the Broadmoor Hotel in Colorado Springs, CO April 26-28 for its 62nd edition, this one held under the theme ?Does size matter (is bigger always better).? With the predictable jokes sprinkled in here and there, and a few unpredictable ones as well, the three-day conference featured a healthy mix of talks about some of the latest technical developments in the field of mineral processing, as well as insightful looks at some new operations in the western United States. This year, the Colorado MPD also launched the Wagner Equipment Student Scholarship program.

Jan 1, 2012

Although out of the ordinary, MINING ENGINEERING is pleased to present a few photographs that typify Western US mining activity during WWII. The photographs, taken by R.G. Zellers at Colorado mining operations between 1942 and 1946, were primarily intended for equipment manufacturers. The pictures capture scenes of hardworking miners during a time when output was essential to fuel a wartime effort. In addition to providing a rare opportunity to step back 40 years and view the equipment and activity common at the time, Zellers' skill with photo composition and his ability to obtain clarity in dimly lit underground operations gives viewers an acute awareness of the dampness and dirt of the mines, and a sense for the miners' limited working space.

Jan 6, 1983

By N. J. Ferguson

An upsurge in demand for Australian coal has seen a much needed programme for a new generation of coal ports. This paper discusses design concepts in planning a large modern terminal, with the 25 Nt/a Port Kembla and the 50 Mt/a Newcastle facilities as practical examples. The need is emphasised for a studied Master Plan, in-built materials handling flexibility and staged development. Trends in bulk ship design and loading methods are noted. Features of these Australian designs include methods of dealing with poor ground conditions, functional civil engineering for environmental protection and optimal marine structure designs.

Jan 1, 1982

By Antonio Rivera

On Nov. 13, 1985, Colombia's Ruiz volcano erupted, killing an estimated 25,000 people and burying several villages. Damages were estimated to be about $US300 million. The following is an account by SME member Antonio Rivera of the volcanic activity that led to the eruption. His account also includes a description of the geography and some geology of the affected area. Mining operations in the area were mostly unaffected, although some operations were forced to close until the roads leading to them could be repaired. Introduction The Ruiz volcano is located on the Central Cordillera of Colombia about 28 km (17 miles) southeast of Manizales, the capital of the state of Caldas. Ruiz is one of nine volcanoes that form a complex volcanic chain within the middle portion of the Central Cordillera. The Cordillera has 30 other volcanoes in the southern part of Colombia. Ruiz volcano Ruiz's elevation is 5200 m (17,060 ft). It is covered by an ice cap estimated to be 20 m (66 ft) thick at its summit, an area that covers 17 km2 (6.5 sq miles). Drainage is composed of several rivers that flow into the Magdalena River on the east and Cauca River on the west. The rivers flowing to the east are Guali, Azufrado, Lagunillas, and Recio. The rivers that flow to the west are Claro, Molinos, and Chinchina. There is a road from Manizales to El Refugio, a ski area located on the northeast flank of the volcano at 4800 m (15,750 ft) in elevation. The Ruiz volcanic complex was built in two stages. The first is a shield type of volcano (mainly lavas) formed about a million years ago. The second is a younger stratovolcano overlaying the ancient one. It consists of lavas and pyroclastics and was built over the past 500,000 years. Twenty-four eruptions of Ruiz are known to have occurred during the last 14,000 years. Its products mainly consist of lava flows, pyroclastic flows, mudflows (lahars), and directed lateral explosions. Historic eruptive record 1595 - Debris avalanche, blast, pyroclastic flows, mudflows, ash flows, and ash fall. 1828-1829 - Ashes (phreatic). 1831-1833 - Gas emissions and ashes. 1845 - Mudflows and pyroclastic flows. 1985 - Sept. 11- Fumarolic activity, phreatic eruption, ash fall, and small mudflows. 1985 - Nov. 13 - Ash and pyroclastic fall, major destructive mudflows (magmato-phreatic eruption). From 1845 through 1984, Ruiz volcano always had a slight fumarolic activity. It was restricted to the crater area. In November and December 1984, the fumarolic activity increased and the first ash emission and vapor-sulfur formation started. Small local earthquakes accompanied these volcanic activities. The volcano had a small erup¬tion on Sept. 11, 1985. It was manifested by phreatic explosions that ejected fragments of the vent and formed ash deposits 25 mm (1 in.) thick around an area 2.5 km (1.5 miles) from the crater. Fine material was blown by the wind and reached Manizales and neighboring areas, producing a small layer of ash up to 10 mm (0.4 in.) thick.

Jan 2, 1986

By W. M. Luff

Introduction The Brunswick No. 12 mine is located about 27 km (17 miles) southwest of Bathurst, New Brunswick. The deposit is a stratiform massive sulfide deposit occurring in a series of sedimentary and volcanic rocks of the Tetagouche Group. These rocks are generally considered to be Ordovician in age. Ore reserves at Brunswick No. 12 are 104 Mt (115 million st) grading 3.72% lead (Pb), 9.01% zinc (Zn), 0.32% copper (Cu), and 97.9 g/t (2.8 oz per st) silver (Ag). Production in 1984 was 3.5 Mt (4 million st) at 3.57% Pb, 8.91% Zn, 0.32% Cu, and 100 g/t (2.9 oz per st) Ag. Total payable silver production that year was 211 t (6.8 million oz). This made Brunswick one of the largest silver producers in Canada. Bathurst-Newcastle area and Brunswick Mining Interest in the Bathurst area was aroused in 1897 when W. Hussey discovered an iron formation at Austin Brook, just south of Brunswick No. 6 deposit. This area, and the current No. 6 area, was explored from 1897 to 1907. Iron ore was mined at Austin Brook from 1907 to 1913 and from 1942 to 1943. Any occurrence of sulfides was overlooked until 1952. In 1952, M. J. Boylen Enterprises investigated the small sulfide body associated with the Austin Brook iron formation. Other electromagnetic anomalies associated with the iron formation were investigated. The No. 6 deposit was found late in 1952, when hole B12 intersected 97.5 m (320 ft) of massive sulfides. The No. 12 deposit, 10 km (6 miles) to the north, was found in 1953. More than 30 massive sulfide deposits have since been identified in the Bathrust area. In the 1950s, St. Joe Lead Co. did extensive test work on the No. 6 and No. 12 deposits, including shafts at No. 12, lateral development at No. 12, and testing at both deposits.

Jan 10, 1986

By Dean S. Rogers

The conventional role of exploration, development and grade control is examined in this paper within the context of the many and varied types of gold occurrences which are found at the Dome Nine. The account endeavours to trace the development of the total ore evaluation process, from diamond drilling through the exploration and drifting stage, to the stope development and planning phase of the operation, with an emphasis on sampling techniques and assaying procedure. The concept of ore reserve calculations is developed and the practice of grade control is described. In summary, the role of the geological, the engineering and the mining department is presented in relation to the contribution each has to make in the evaluation and exploitation of ore from one of the world's classic Archean gold deposits.

Jan 1, 1984

Commercialisation of outcomes from research projects is a process often poorly understood and managed, but has the potential to achieve significant benefits for the industry and community as a whole. JKTech Pty Ltd was established in 1986 to transfer viable research outcomes from the Julius Kruttschnitt Mineral Research Centre (JKMRC) at The University of Queensland, Australia. This paper describes successful and unsuccessful examples of commercialisation by JKTech over the years, and draws some conclusions as to the factors that contribute to success and failure in technology transfer.

Jan 1, 2012

By Albert Ruiz

The 2,250-MW, coal-fired Navajo Generating Station located in Page, AZ draws water from Lake Powell using submersible pumps installed in five inclined shafts. Drought threatens to lower the reservoir to below the existing intakes. A system of new steel-lined intake shafts located on the same site was required for uninterrupted plant operation. The small size of the site, and the need to keep the existing system in operation, required detailed designs and placed significant limitations on construction equipment and activities. The Navajo Sandstone that forms the near vertical shoreline of the reservoir is 98 percent very fine grained quartz, highly abrasive and contains highly fractured intervals that presented numerous challenges to drilling the new 152-m (500-ft) deep, 109-cm (43-in.) diameter intake shafts inclined 23° to 26° from vertical. Spatial constraints, submersible pump design and operational criteria required that each shaft have a unique inclination and orientation and hit a small breakout target located 76 m (250 ft) under water. Sophisticated drilling equipment and techniques as well as state of the practice downhole survey technology and methods were used to make adjustments and maintain drilling accuracy with less than 1 percent deviation. Environmental requirements mandated water as the drilling fluid and grout was not allowed in to the lake under any circumstances. The shafts were videotaped and the breakout locations were examined using an underwater remotely operated vehicle (ROV) to verify shaft locations and rock conditions, and to guide placement of pneumatic packers to ensure grout did not transmit to the lake during the steel liner installation. In anticipation of the invasion of quagga mussels, the shaft design included an allowance for a chemical dosing system and a copper-rich alloy at the exposed portions of the steel liner.

Jan 1, 2011

By Behrooz Abbasi, Seyedsaeid Ahmadvand, Thom Seal, Babak Azarfar, Bryan Ulrich

Hydro-Jex® is a new enhanced method for heap leach treatment with significantly higher mineral recovery. In this case study at the Los Filos Mine in Mexico, the Hydro-Jex operation is evaluated for heap leach stability. This is pursued by numerical modeling of the heap leach pad stability and well monitoring of the phreatic surface before and after the Hydro-Jex operation. Experimental and numerical results both indicate an improvement in mineral processing under the influence of Hydro-Jex. Numerical results show an insignificant decrease and a significant increase in stability during and after Hydro-Jex injection application, respectively. The integrity of the liner is maintained in both cases. The zonal injection pressure, operationally below the overburden pressure, is found to be negligible compared with the dimensionality of the heap, and stability of the structure is not exposed to any significant risk, even up to 25%above overburden pressure. Furthermore, heap leach factor of safety increases after Hydro-Jex application. This is attributed to breakdown of the water solution build-up and thus a decrease in the phreatic surface depth below the top of the pad. It is suggested that injection wells be drilled, based on thorough geophysical data, in locations where overcompaction of heap material results in water solution build-up and pore pressure enhancement. Compared with traditional heap leaching, the Hydro-Jex technique not only expedites mineral processing by increasing chemical kinetics extraction but also increases the stability of the heap by unclogging drains.

Jun 29, 2020

By S. S. M. Chan

The design of most underground support systems has largely been based upon empirical rules. This design method has proven to be satisfactory in most cases as witnessed by the number of successfully completed works. However, the adequacy of this approach to the developing technology of ground support systems associated with deep excavation has not been substantiated. In cases where the material has definite time-dependent behavior parameters, rules of past experience become extremely vague and conservative. The Spokane Mining Research Center is currently engaged in extensive research to develop rational design methods for underground structures which will account for the many interacting factors such as in-situ properties of the rock mass, excavation methods, proposed types of support system, construction sequence, and environmental variables. The information presented in this paper pertains to only a segment of the research program,

Jan 1, 1971

By M. A. D. Azevedo, J. D. Miller, R. Kobler, E. Mutkowska

Up to 3 million tons of automotive shredder residue (ASR) is generated annually in United States. Plastics are the most valuable component of the ASR material making up approximately 25% of the total weight. In order to reuse these plastics, a selective process is required to separate each plastic, with very high purity and favorable economics. One separation technique, which may be able to selectively recover the plastics from ASR, is flotation. The preliminary flotation results have demonstrated that acrylonitrile-butadiene-styrene (ABS) and polycarbonate (PC) can be selectively separated from the model ASR feed, the PC/ABS/PA 66 system, by appropriate control of the surface chemistry.

Jan 1, 2001

By S. R. S. Sastri

By using the data of E.A. Hersam and F.C. Bond's equation for energy consumption in comminution, a method was developed to analyze the performance of industrial jaw crushers. The study showed that industrial jaw crushers are generally operated below capacity. The study also showed that industrial jaw crushers generally have sufficient installed power to operate at, full capacity. The method presented can be used to estimate the capacities and power requirements of jaw crushers.

Jan 1, 1995

By Mike Lewis

"Descending several stories down a metal staircase into a shaft spanning a quarter city block -- soon to become Roosevelt Light Rail Station in Seattle, WA -- visitors are greeted with four perfectly round, precast concrete-lined horizontal holes leading deep into the earth. The sound of water trickling out from a small drainage trough can be heard over the faint echoes of construction within. Upon entering, the light is dim, but the air is clear with barely a dust particle flowing through the sunbeams. This type of air quality is only accomplished with diligent controls, and JCM Northlink, the company in charge of building the Northgate Link Extension Project, is taking those measures seriously.Commissioned by Sound Transit, JCM is a joint venture of three companies: Jay Dee Contractors, Frank Coluccio Construction Co. and Michels Corp. The tunnels JCM constructed are intended to provide fast, reliable underground rail service, as well as relieve one of the region’s most congested traffic areas. The $440 million project will connect the Northgate, Roosevelt and University District neighborhoods north of Seattle to the downtown corridor and SeaTac airport further south.The scope of this project includes excavation for two light rail stations, boring of two parallel 5 km- (3.3-mile) long light rail tunnels in six runs and the construction of 23 cross passages. Begun in 2014, Sound Transit estimates that crews excavated more than 382,000 m3 (500,000 cu yds) of soil and installed 7,352 precast concrete tunnel liner rings during the shaft construction and boring phase. Now that tunnel boring is complete, JCM is in the process of constructing the cross passages, which act as maintenance areas and escape routes for passengers. Throughout the entire process, the company has utilized atomized mist to control particle emissions.“Our dust control needs change at every phase of the project and don’t go away until the project is fully complete,” said a JCM safety representative. “We found that different dust suppression technologies were needed at different intervals, but atomized mist seemed to fulfill our needs at every step.”"

Jan 9, 2017

By R. Heiser, J. Vendetti, B. P. Connor, E. J. Haas

Health and safety indicators help mine sites predict the likelihood of an event, advance initiatives to control risks, and track progress. Although useful to encourage individuals within the mining companies to work together to identify such indicators, executing risk assessments comes with challenges. Specifically, varying or inaccurate perceptions of risk, in addition to trust and buy-in of a risk management system, contribute to inconsistent levels of participation in risk programs. This paper focuses on one trona mine’s experience in the development and implementation of a field-level risk assessment program to help its organization understand and manage risk to an acceptable level. Through a transformational process of ongoing leadership development, support and communication, Solvay Green River fostered a culture grounded in risk assessment, safety interactions and hazard correction. The application of consistent risk assessment tools was critical to create a participatory workforce that not only talks about safety but actively identifies factors that contribute to hazards and potential incidents. In this paper, reflecting on the mine’s previous process of risk-assessment implementation provides examples of likely barriers that sites may encounter when trying to document and manage risks, as well as a variety of mini case examples that showcase how the organization worked through these barriers to facilitate the identification of leading indicators to ultimately reduce incidents.

Jan 1, 2018

By R. Heiser, J. Vendetti, B. P. Connor, E. J. Haas

Health and safety indicators help mine sites predict the likelihood of an event, advance initiatives to control risks, and track progress. Although useful to encourage individuals within the mining companies to work together to identify such indicators, executing risk assessments comes with challenges. Specifically, varying or inaccurate perceptions of risk, in addition to trust and buy-in of a risk management system, contribute to inconsistent levels of participation in risk programs. This paper focuses on one trona mine’s experience in the development and implementation of a field-level risk assessment program to help its organization understand and manage risk to an acceptable level. Through a transformational process of ongoing leadership development, support and communication, Solvay Green River fostered a culture grounded in risk assessment, safety interactions and hazard correction. The application of consistent risk assessment tools was critical to create a participatory workforce that not only talks about safety but actively identifies factors that contribute to hazards and potential incidents. In this paper, reflecting on the mine’s previous process of risk-assessment implementation provides examples of likely barriers that sites may encounter when trying to document and manage risks, as well as a variety of mini case examples that showcase how the organization worked through these barriers to facilitate the identification of leading indicators to ultimately reduce incidents.

Jan 1, 2017

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 Theophilus Mensah, Kwame Awuah-Offei

Engineers face significant challenges when determining what geometry provides the most profitable and safe stope for extraction. Several techniques and optimization algorithms have been developed in recent years, but most fail to find optimal solutions because they are heuristic or LP-based without efficient geometric constraints. This paper presents a two-dimensional binary linear programming (BLP) model for determining the optimal combination of blocks in a stope that maximizes the economic value of the layout of stopes for a sublevel deposit. The work draws from Queyranne and Wolsey’s (2017 & 2018) formulations of tight constraints for bounded up/down times in production planning problems to formulate novel and efficient geometric constraints along with geotechnical and grade constraints for the BLP stope layout optimization problem. Results from the model indicate that it is possible to formulate efficient shape constraints in LP-based approaches. The model used for the numerical example contained 144 valuable blocks out of 774 blocks, which translates into an economic value of $53.21M. The BLP model selected 60 valuable blocks and 13 waste blocks that met all constraints translating into a maximum economic value of $34.4M in 1.83 hours within a gap tolerance of 0.00%.

Jun 25, 2023