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By G. R. Brunskill

The molybdenite flotation plant at Magma Copper Company, San Manuel concentrator has been in operation since 1956. In January of 1980 the plant was converted from a hydrogen peroxide - ferrocyanide process to the current sodium cyanide - sodium hydrosulfide process. This paper is an operational review of Magma Copper Company's molybdenite recovery circuit, column cell flotation experience and use of on- stream x-ray flourescence analysis.

Jan 1, 1985

By Joseph Ribak

Grunerite asbestos (amosite) has been shown in epidemiological and experimental animal studies to cause lung cancer, mesothelioma and pulmonary fibrosis commonly referred to as asbestosis. An overview of the human and experimental animal studies describing the health hazards of grunerite asbestos (amosite) is presented. Of the many human studies describing the health hazards of asbestos, only three factories using mainly, if not exclusively, grunerite asbestos (amosite) have been studied. The first is a series of reports on a cohort of 820 workers from a plant located in Paterson, NJ. Among this cohort, 18.7% died of lung cancer and 17 mesotheliomas occurred. The Paterson factory closed in 1954 and moved to Tyler, Texas where it operated until 1972. Among the 1130 former workers in the Tyler plant 6 mesotheliomas were reported with 15.8% lung cancer mortality. The third grunerite asbestos (amosite) exposed cohort was an insulation board manufacturing facility in Uxbridge, United Kingdom. Here 17.1% of the workers died of lung cancer and 5 mesotheliomas occurred. The lung content from 48 Uxbridge workers was analyzed by analytical transmission electron microscopy for mineral fibers. The relationship between grunerite asbestos (amosite) concentrations in the lung correlated with grades of fibrosis and asbestos bodies and was lower than the concentration found in the cases with malignant tumors. The lung cancer cases contained more grunerite asbestos (amosite) than mesothelioma cases, and in the cases of non-alignant disease the concentrations were still lower. In both types of malignancies the concentration of grunerite asbestos (amosite) was very high-over a billion fibers per gram of dried lung tissue. Occupational exposure to airborne concentrations of between 14 and 100 fibers of grunerite asbestos (amosite) per milliliter after 20 year latency causes marked increases in lung cancer, mesothelioma and pulmonary fibrosis (asbestosis). © 2007 Elsevier Inc. All rights reserved. Keywords: Grunerite asbestos; Amosite; Mesothelioma; Asbestosis

Jan 1, 2007

By P. Zhang

A multiyear, comprehensive study of flotation reagents used in phosphate beneficiation was conducted. The study involved the evaluation of pure fatty acid compounds, comparison of various anionic collectors and testing of iso-acids. Various C12 to C22 fatty acids were tested as Florida phosphate collectors. The saturated fatty acids were found to be very poor collectors when using the standard conditioning procedure, whereas the unsaturated C16 to C22 fatty acids showed fair to good phosphate collecting ability. The C18 fatty acids oleic, impure oleic and linoleic and the C20 eicosenoic acid were shown to be the best phosphate collectors. The best flotation results were obtained using Liqro GA tall oil and oleic acid. Four isostearic/iso oleic acid type fatty acid collectors were compared with a commercial grade oleic acid and with Liqro GA tall oil as phosphate collectors using standard laboratory conditioning and flotation procedures. The most selective collector evaluated was Century 1108, a high isostearic acid-type reagent. However, it was concluded that this excellent-performing reagent was too expensive for commercial use. Overall, the most promising reagent was probably Century MO-5. This collector is essentially an iso-oleic acid/stearic acid mixture (not isostearic acid), and it costs much less. This program laid a sound foundation for developing single collector, all anionic flotation processes.

Jan 1, 2009

By A. Vien

A major thrust in Industrial automation over the past few years has been the exploration and incorporation of higher level (supervisory and optimizing) control strategies aimed at more fully exploiting the existing control system infrastructure. There is little doubt that this is worthwhile pursuit, however, one must not lose sight of the maintenance and development requirements of the basic control system. Statistics on loop performance indicate that this too is an area of considerable potential. In this paper the authors look at some of the less elegant, but arguably equally important issues in mineral processing plant control. The focus is on controller structures, loop tuning, sampling, filtering, and some of the other principal components of the regulatory control foundations. In many cases significant improvements In control performance can be achieved by getting back to the basics.

Jan 1, 1998

By D. J. Shields

The Sustainable Minerals Roundtable was established in 1999 to develop a set of national level indicators to measure the contributions of mineral and energy systems to sustainable development in the USA. The U.S. Forest Service and the U.S. Geological Survey are sponsors of the Sustainable Minerals Roundtable, with meetings convened by the University of Nevada, Reno. Eighteen meetings have been held in various regions of the United States to receive input from different communities of interest. Indicators are being prepared under four criteria: legal and institutional, productive capacity, environmental impact, and socio-economic. This paper reviews the process followed by the Sustainable Minerals Roundtable, and presents the priority indicators.

Jan 1, 2003

By Greg Sheppard, Eduardo Nebot

Australian researchers have developed new technologies aimed at improving safety and productivity at openpit mines. A data acquisition and feedback system for electric rope shovels has been shown to substantially reduce cycle times and decrease excessive machine duty caused by stalls. This data acquisition system was developed by the Cooperative Research Center for Mining Technology and Equipment (CMTE). It has been tested on a P&H 4100A shovel at Coal & Allied’s Hunter Valley operations and a P&H 4100XPB at BHP Billiton Mitsubishi Alliance’s Goonyella Riverside Mine in Central Queensland. In addition, CMTE member P&H Mine Pro Services has used the technology to acquire field data from a P&H 4100XPBrope shovel at RAG’s Belle Ayr Mine in Wyoming’s Powder River Basin.

Jan 1, 2002

A comprehensive understanding of the effects of autoclave configuration (batch, semi-batch, continuous) on the residence time necessary to achieve a target conversion is a prerequisite for design of commercial scale autoclaves. Particle size distribution, mineral and reagent concentrations, temperature and mixing also influence the conversion. This paper outlines the bases of using test data to predict performance of commercial scale autoclaves. Recommendations for coordinating test program design with selection of scale-up method are provided. Examples are given to illustrate the different levels of engineering effort needed to meet corresponding levels of design optimization and accuracy.

Jan 1, 1998

By Georgios Kalamaras, Chiaia Dinu, Platania Paolo, Alessio Carlo, Giampiero Cirvegna, Claudio Santucci

The Project alignment initiates north of Pinerolo, along the State Road 23[S.S. 23] that is one of the principal arteries to the northwestern Alps where a number of Olympic events for the 2006 Winter Games will be held. The 3.5 km ring road bypasses the Porte habitat by traversing twice the Chisone River. It consists of the following principal structures [Figure 1]: San Martino bridge [130 m in four bays] Prarostino viaduct [130 m in four bays] Craviale tunnel [1055 m] Turinella bridge [a 50 m long bridge that connects the two tunnels] Turina tunnel [665 m] Malanaggio viaduct [350 m in 9 bays]. The road section is 13 m wide and is made up of two 3.75 m lanes, a hard shoulder [1.50 m wide] and a 1.25 m wide curb for each lane. The Project maximum velocity is 100 km/h.

Jan 1, 2005

By K. H. McDaniel, K. G. Wallace

This paper describes the development of a Windows-based interactive mine ventilation simulation software program at the Waste Isolation Pilot Plant (WIPP). To enhance the operation of the underground ventilation system, Westinghouse Electric Corp. developed a program called WIPPVENT. While WIPPVENT includes most of the functions of the commercially available simulation program VNETPC from Mine Ven- tilation Services Inc. and uses the same subroutine to calculate airflow distributions, the user interface was completely rewritten as a Windows application with screen grap-hics. WIPPVENT is designed to interact with WIPP ventilation-monitoring systems through the sitewide central monitoring system. Data (e.g., air quantity and differential pressure) can be continuously collected from the underground ventilation remote-monitoring and control system and from the mine's weather stations (psychrometric data). Furthermore, WIPPVENT incorporates regulator characteristic curves specific to the site. The program utilizes this data to create and continuously update a real-time ventilation model. This paper discusses the design, the key features and the interactive capabilities of WIPPVENT.

Jan 1, 1998

By K. H. McDaniel

This paper describes the development of a Windows-based interactive mine ventilation simulation software program at the Waste Isolation Pilot Plant (WIPP). To enhance the operation of the underground ventilation system, Westinghouse Electric Corp. developed a program called WIPPVENT. While WIPPVENT includes most of the functions of the commercially available simulation program VNETPC from Mine Ventilation Services Inc. and uses the same subroutine to calculate airflow distributions, the user interface was completely rewritten as a Windows application with screen graphics. WIPPVENT is designed to interact with WIPP ventilation-monitoring systems through the sitewide central monitoring system. Data (e.g., air quantity and differential pressure) can be continuously collected from the underground ventilation remote-monitoring and control system and from the mine's weather stations (psychrometric data). Furthermore, WIPPVENT incorporates regulator characteristic curves specific to the site. The program utilizes this data to create and continuously update a real-time ventilation model. This paper discusses the design, the key features and the interactive capabilities of WIPPVENT.

Jan 1, 1997

By A. Guzman

The design and construction of a new 140-ton-per-day R. O. M. phosphate rock scrubbing and washing plant was undertaken by Western Knapp Engineering Company, a Division of Arthur G. McKee and Company, for the J. R. Simplot Company, Minerals and Chemical Division, Pocatello, Idaho. The new plant replaces the owner's existing facilities at Conda, Idaho, seven miles northeast of Soda Springs in the southeast corner of Idaho. Replacement of the existing facilities became necessary because of loss in production and recovery. These losses were due in part to varying grades of raw ore from the mine and to the type of process equipment used in the old plant to upgrade the ore. Increase In production and grade was further necessary by demands created by expansion of facilities in Pocatello, Idaho, where all process ore from this plant is shipped. The new process scheme includes an ore-feeding system, scrubbing, screening, classification, wet cycloning, attritioning, filtering, drying, storage and shipping facilities. Space was also left for future increases of scrubbing and classification capacity and for heavy media separation. It is the purpose of this paper to take up some of the considerations necessary in the design of small mills in order to achieve the desired objectives of a successful plant, such as production, minimum operating cost and maintenance cost.

Jan 1, 1969

By Pierre Dosmond

In ore mining technology, the loading and hauling operations are undoubtedly the area where the most spectacular progress has been made during the last twenty years. I shall draw some examples from the Eastern France iron ore mines which I how well and whose production of 62 million tons for 1962 and 1963 constitute a worthwhile experience worldwide. The iron ore deposits of Lorraine are of sedimentary origin. They contain many mineralized horizons with workable seams situated from 330 to 830 ft. in depth. The dip of these seams is generally less than six percent. Their thickness varies from 6 to 23 ft. All seams are not workable throughout the whole area of occurrence, but in some mines there are five mineable seams in the same vertical section, with from 5 to 20 ft. of barren ground intervening between them. The iron content of the mineral varies from 28 to 36 percent. Specific gravity of the ore is 156 lb. per cu. ft. m place and 100 lb. per cu. ft. blasted. Reserves of iron ore in the Lorraine region are estimated at six billion tons with an iron content of more than 28 percent. These mines operate by means of rooms and pillars process, with pillar robbing; the final recovery is very good and averages 90 percent. Some years back, competition from richer, imported ores incited these mines to make constant efforts to increase their productivity and reduce mining costs, thus placing them in a leading position in mining technology, as evidenced by the dramatic evolution of their output per manshift (Figure No. 1).

Jan 1, 1970

By A. M. Esteves

This paper addresses the question ?What constitutes the right level of investment in community goodwill?? Mining companies are still grappling with this subject even though the business case for community investment has been accepted at a general level, as a strategy for competitive differentiation, risk mitigation and a desire to deliver - and to be seen to deliver - a ?net benefit? to affected communities. Gaining senior management commitment to long term social projects, by definition characterized by uncertainty and complexity, is made easier if projects are shown to benefit the site?s strategic goals. Case study research amongst mining companies, including interviews with social investment decision-makers, has assisted in developing a SI-DAT (Social Investment Decision Analysis Tool), a decision model for evaluating social projects in order to create value for both the company and community. Multi-criteria decision analysis techniques integrating business planning processes with social impact assessment have proved useful in assisting mining companies think beyond seeking access to required lands and peaceful relations, to how they can meet their business goals and contribute to regional development.

Jan 1, 2007

By B. A. Carbon

Western Australia is the largest state in Australia with an area one and three quarter times the size of Texas. Most of the State is desert or semi-desert, and only the southwest corner is heavily populated. The State has a population of one and a half million people, and one million of these live in and around the city of Perth. Perth is located on the narrow Swan Coastal Plain and is flanked by the Indian Ocean and the Darling Plateau. The Darling Plateau is an ancient peneplain rising some 300 metres above sea level, and forms an important resource base for the population.

Jan 1, 1984

By Russell L. Dahl

In a continuing effort to improve plant efficiency, United States Steel's Atlantic City Ore Operations completed the rubber lining of its balling drums in late 1982. This resulted in benefits of reduced bentonite consumption, reduced maintenance costs, improved production rates, and lower power consumption. These advantages far outweigh the disadvantages of increased oversize production and increased surging on the roll screen sizing devices. Certain operating characteristics and variables are discussed herein.

Jan 1, 1983

By J. R. Heberger

"“Safety Pays in Mining” web application developed by the U.S. National Institute for Occupational Safety and Health Mining Program, helps mines determine the potential costs associated with mining injuries. This web app groups injuries by type, either by the cause of the injury or by the nature of the injury. When the user selects one of more than 30 common types of mining injuries, the app provides information on the distribution of costs of workers’ compensation claims for that type of injury. Based on other user inputs, the app will estimate the total costs of the selected injuries, including an estimate of additional indirect costs, the estimated impact of total injury costs on mining company profits, and provide some examples of other items, such as services or equipment, on which companies could spend the savings that result from the prevention of injuries. This paper reviews the app by discussing its development, how it is used to show the true costs of mining injuries, and how mines can benefit from using it.IntroductionInjuries on the job cause pain and suffering. They can also profoundly affect profits and daily operations. In addition to paying direct costs or increased premiums for workers’ compensation insurance, a company might need to pay overtime for other workers to fill an injured worker’s job role, cover training costs for a replacement worker or divert administrative resources in the wake of an injury. “Safety Pays in Mining” is a web app that estimates the distribution of these injury costs and assesses the impact that occupational injuries have on a company’s profits.The costs of specific types of occupational injuries in mining are not readily available as mining and insurance companies do not usually share this information. As a consequence, companies only have cost information based on previous experience with their own employees. Therefore, if a mine never experienced a finger amputation for one of its miners, for example, it would not be aware of the possible costs associated with this type of injury. In addition, injury costs are unique in that the cost distribution is so wide that just using the average cost of a specific injury type does not provide adequate information. Some injuries involve immensely high costs, and even though the risk of these high-cost injuries occurring is low, mines need to be aware of the potential impact on their company’s financial health."

Dec 1, 2018

By S. A. Anzalone

The Helvetia copper deposit is a large undeveloped Laramide porphyry copper system located in the Santa Rita Mountains, Pima County, Arizona. This porphyry copper system consists of four areas of copper mineralization: Rosemont, Peach-Elgin, Broadtop Butte, and Copper World. Asarco refers to the four areas collectively as the "Helvetia Deposit". Mineralization and alteration are primarily contact pyrometasomatic, and zoning of hydrothermal alteration and sulfide mineral assemblages are similar to those observed at the Twin Buttes and Mission copper mines located approximately 32 km west of Helvetia. Asarco acquired the Helvetia Deposit in 1988 and has continued the exploration and development effort since then. A considerable amount of excellent geological work has been completed in the area but little information has been published on developments since the mid-1950's. The geology of the deposit as developed by numerous geologists over the past 75 years and the large, bulk tonnage low grade copper deposits outlined in recent years will be briefly reviewed in this paper.

Jan 1, 1992

By J. R. Heberger

"The Safety Pays in Mining web application, developed by the National Institute for Occupational Safety and Health (NIOSH) Mining Program, helps mines determine the potential costs associated with mining injuries. This web app groups injuries by type, either by the cause of the injury or by the nature of the injury. When the user selects one of over 30 common types of mining injuries, the app provides information on the distribution of costs of workers’ compensation claims for that type of injury. Based on other user inputs, Safety Pays in Mining will estimate the total costs of the selected injuries, including an estimate of additional indirect costs, the estimated impact of total injury costs on mining company profits, and provide some examples of other items (services, equipment) on which companies could spend the savings that result from the prevention of injuries. This paper reviews the Safety Pays in Mining web application by discussing the development of the app, how it is used to show the true costs of mining injuries, and how mines can benefit from using this app. INTRODUCTION Injuries on the job cause pain and suffering. They can also profoundly affect profits and daily operations. In addition to paying direct costs or increased premiums for workers’ compensation insurance, a company might need to pay overtime for other workers to fill an injured worker’s job role, cover training costs for a replacement worker, or divert administrative resources in the wake of an injury. Safety Pays in Mining is a web app that estimates the distribution of these injury costs and assesses the impact that occupational injuries have on a company’s profits. The costs of specific types of occupational injuries in mining are not readily available as mining and insurance companies don’t usually share this information. As a consequence, companies only have cost information based on previous experience with their own employees. Therefore, if a mine never experienced a finger amputation for one of its miners, it would not be aware of the possible costs associated with this type of injury. In addition, injury costs are unique in that the cost distribution is so wide — with half of the injuries in our dataset having mean costs higher than 90th percentile costs — just using the average cost of a specific injury type does not provide adequate information. Some injuries involve immensely high costs, and even though the risk of these high-cost injuries occurring is low, mines need to be aware of their potential impact on their company’s financial health."

Jan 1, 2018

By J. S. Hall

The performance of a full-scale balling drum circuit is well known to fluctuate, and is difficult to control. The fluctuations stem from causes that are not readily quantifiable. Results from plant tests show that surging of the recycle tonnage is dependent, inter alia, on the method of bentonite addition, small variations in drum or cutter bar speed and the method of drum water addition. This paper presents detailed observations from experiments on full-scale drum circuits, including preliminary results of a computer measurement and control scheme. Size distributions measured at points along an industrial drum are presented, together with the results of a mathematical model fitted to one plant data set. Model predictions are also included emphasizing the importance of screen performance on circuit stability.

Jan 1, 1983

By L. A. Puchkov

Problems of how to use artificial intelligence (AI) methods and expert systems (ES) to control complex industrial projects have lately become significant in practical terms. Mining ventilation systems undoubtedly belong to complex multi dimensional objects of control with stochastic nonstationary and nonlinear processes. Formal models based on automated ventilation control, do require awkward algorithmic solutions, moreover, a number of tasks become the operator's headache, and the quality of their solution depends on his experience and intuition. These tasks include: - identifying pre-accidental situations and determining their causes; - making well-grounded decisions with regard to changing ventilation regimes, forecast of mining operations taken account of; - controlling ventilation systems in emergency situations, e.g. when in accident, etc. It is in this context that we have for a number of years been investigating how to practically use AI methods for operative control in dynamic aero-and-gas mining processes, one of our research directions being devoted to working out a consulting programme for the ventilation system operator. Our researching and modeling problem was identification of aero-and-gas situation in different parts of ventilation network and its interpretation in order to determine possible causes for gas regime changing and unexpected consequences. We would single out the following stages in this task: I. Operative information procession coming to the data base from the sensors and analysis of hypothetical versions (using the associative rules base) with regard to factors which have caused significant parameter fluctuations (e.g. C%(t), H(t), Q(t) etc.)., 2. Selection of hypotheses in the knowledge base and forming conclusions in accordance with reliability scale. 3. Clarifying the obtained conclusions in dialogue with the operator. 4. Correcting the associative rules base.

Jan 1, 1992