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By P. G. Martin

"As the speed of business has continued to increase over the last decade, the focus on real-time control of the performance of both stationary and mobile assets has become an increasing priority. Traditionally the maintenance team has been focused on the management of the availability of assets while the operations team has been focused on the throughput of those same assets. Typically operations and maintenance teams worked almost independently in spite of the fact that they were both working with the same assets. Part of the problem has been their traditional performance measures which have often been diametrically opposed. Recent advancements in the area of real-time performance measures and decision support have helped to drive higher levels of collaboration between operations and maintenance leading to real-time asset performance control and higher levels of business performance. This paper will explore the forces driving the need for changes, present an effective approach to the definition of the most appropriate business performance measures, and examine the effectiveness of contextualized real-time decision support resulting in asset performance control. TRADITIONAL APPROACHES TO ASSET PERFORMANCE MANAGEMENT In most industrial operations the phrase asset performance management is synonymous with maintenance of the industrial assets. This is the way industry has viewed asset management and asset performance management for decades. This is a very limited perspective that is serving to constrain the profitability of industrial operations. As industrial organizations began to form following the Industrial Revolution, the complexity of the operations forced an organizational design based on specialization. No single person could understand all of the aspects of an industrialized operation. This was particularly true at the plant floor level where the operation and maintenance of the industrial equipment required very different skillsets and training. To accommodate the vast differences most industrial organizations set up operations teams to run the equipment and maintenance teams to keep the equipment available to the operation. Both teams were dealing with the same industrial equipment but from very different perspectives and with very different performance measures. Typically the operations team was measured on maximizing the output of the equipment – or throughput. On the other hand the maintenance team was measured on the uptime – or availability of the equipment."

Jan 1, 2015

Modern coal cleaning technologies have allowed coal preparation facilities to become quite efficient at removing sulfur compounds, waste rock and low grade coals from run of mine coal. Up to 50% of the raw mined coal stream may end up as refuse, particularly when the coal originates from longwall mining operations, or is high in partings, rock and impurities. The refuse materials vary from coarse materials removed by physical screening to very fine materials removed by floatation and density separation processes. Coal refuse piles are also known by a variety of other names including "waste dumps", "gob piles" and "slate dumps". The potential hazards of improperly reclaimed refuse include contamination of surface and groundwaters by acidic leachates and runoff, erosion and sedimentation into nearby watersheds, spontaneous combustion, disturbance of topsoil borrow areas, and damage from landslides should large slope failures occur. Many of these problems have been particularly acute for abandoned refuse piles, and modern regulations attempt to minimize the environmental impact of coal refuse disposal operations.

Jan 1, 1993

By A. R. Bell

Rio Algom Limited are currently undergoing a major expansion of their mining operations in the Elliot Lake area. To date this has involved the increase of output at the Quirke Mine from 4080 to 6350 tonnes per mill day (4500 to 7000 tons), the rehabilitation of the Panel Mine to produce at the rate of 2990 tonnes per mill day (3300 tons) by 1980, and the rehabilitation of the Stanleigh Mine to produce 4540 tonnes per mill day (5000 tons) by 1984. In addition, the planning for the rehabilitation of the Milliken Mine to produce 4990 tonnes per mill day (5500 tons) is now underway. This major expansion is taking place at a time of increasing awareness of occupational health matters and has involved very high capital expenditures and detailed planning related to the ventilation system to endeavour the provision of an acceptable environment. The paper discusses the ventilation systems, established and proposed, and relates them to historical and current data on mine air contaminants.

Jan 1, 1980

By Yang Ge, Yuzhu Pan, Mansheng Chu, Jue Tang, Cong Feng, Lihua Gao, Zhenggen Liu

Increasing attention is being paid to laterite nickel ore as an alternative to nickel sulfide ore to act as a feedstock for nickel metal production. While laterite nickel ore accounts for a lion’s share of global nickel resources at approximately 72 percent, it accounts for only 42 percent of the world’s nickel production. In addition, the processing of nickel sulfide ore is confronted with enormous challenges due to deeper drilling requirements, higher production costs and depleting reserves. The nickel content in the nickel laterite ore associated with hydrated iron oxides and silicate minerals limits the application of physical beneficiation methods for the removal of iron. Thus, magnetic reduction roasting followed by magnetic separation has been regarded as one of the attractive routes to concentrate and separate the valuable metals from the impurities. 

By M. S. Klima

Proper analysis of washability data can lead to the development of a maximum yield coal preparation plant flow sheet. Simulations, as simple as spreadsheet mass and water balancing, are important in examining yield maximization and middlings liberation. Key to such attribute tracking flow sheet simulations is the distribution model, expressing the probability of a species reporting to the product stream. There are many such models in the literature. This paper examines a functional form that can represent or fit most of the proposed distribution functions.

Jan 1, 1997

By S. C. Torma

Sources of lead contaminated soils are numerous, i.e., the uses of leaded gasoline, lead-based paints, leaded pesticides, solders, smelting of lead concentrates, refining of lead products, automobile demolition, recycling of lead batteries, and so on. Conservative estimation by the US Environmental Protection Agency, EPA, indicated that several thousand lead contaminated sites are awaiting remediation. The current remediation technologies include immobilization, reclamation and soil washing. In this paper, the above remediation technologies will be reviewed, and where appropriate, the economics of processes discussed and future possibilities indicated.

Jan 1, 1996

By J. R. Muhm

Environmental due diligence investigations, also known as Phase I Environmental Audits, are increasingly important to major investors, venture partners, or prospective purchasers or sellers of mineral properties. Knowledge of environmental risks associated with a property will allow better appraisal of a property's overall desirability prior to completing the transaction. It is possible that the cost of environmental cleanup could exceed the value of the property. Topics appropriately investigated include permit status, water quality, past use of the property, hazardous materials management, storage tanks, public records pertaining to the environmental character of the property, and environmental costs.

Jan 1, 1991

By V. M. Torres

Arapiraca ore deposit has a mixed chalcopyritelbornite mineralogy, with a copper head grade of 0.7%. The reserve size does no allow profitable exploration by grinding/flotation. The technical feasibility of exploring the reserve by heap leaching was studied. Preliminary agitation tests indicated 85% copper recovery. To simulate heap leaching, column tests were performed. The tests included different ore types and acid addition levels. Operating at pH range 1.6-1.8, 67% copper extraction was achieved. Also, it was found an empirical correlation between the operation pH range, copper extraction and acid consumption.

Jan 1, 1996

By D. P. Gold

Major sources and reserves of Cb/Nb, Ta, REE, Y, Sc, Zr, Hf, Cu, apatite and vermiculite may be concentrated in primary and secondary minerals associated with different stages and depths of emplacement in carbonatite complexes and kindred alkalic intrusive rocks. Exploration targets include: apatite and pyrochlore (Nb) in the plutonic and hypabyssal core and ring-dikes: bastnaesite (REE), strontianite, barite and fluorite in hydrothermal veins and cone-sheets (subvolcanic setting): thortveitite (Sc,Y) and vermiculite in metasomatized aureoles (fenites): high grade eluvial deposits of apatite and pyrochlore, and secondary REE, Nb, Ti. and V-minerals in supergene and weathered zones.

Jan 1, 1991

By Carlos A. Jaramillo, Seng Hing Ngu

"The Murum Hydroelectric Project is a 944-MW development consisting of a 145 meter high RCC dam, two 2660 meter long, 9 meter excavated diameter upper pressure tunnels, surge shafts, two 950 meter long 7 even meter OD penstock tunnels and a surface powerhouse. The project is located in the eastern section of the State of Sarawak, Malaysia, about 200 kilometer from Bintulu, in the Rajang Fold-Thrust Belt, an Upper Cretaceous to Upper Eocene fold and thrust belt that extends under most of Sarawak. The Belaga Formation consists of a thick sequence of deep marine sediments currently appearing as steeply dipping strata of thin to thick bedded, fine to medium grained sandstone interbedded with argillaceous rocks, resulting on a “Flysch” type geologic environment. The project pressure tunnels were excavated perpendicularly to these strata resulting on frequent change on rock conditions and behavior, and required rock support. This paper describes the characterization of the rock mass, design of rock support, and incidents during construction. Particularly interesting were convergence issues in Tunnel 1 resulting from Tunnel 2 excavation. INTRODUCTION The Murum Hydroelectric Project is located in the eastern section of the State of Sarawak, Malaysia, about 200 kilometers from Bintulu, and upstream of the Bakun Hydroelectric Project. The project consists of a 145 meter high RCC dam, a 50 meter high intake tower, two nine meter OD and 2660 meter long upper pressure tunnels, two nine meter OD and 175 meter long vertical shafts, two 25 meter diameter and 80 meter deep surge tanks, two seven meter OD and 950 meter long penstock tunnels and four seven meter OD and 50 meter long branch tunnels, two 8 meter diameter to 3.4 meter diameter and 1400 meter long penstocks installed within the shafts, penstock tunnels and branch tunnels ending in a powerhouse with 944 MW installed capacity. LAYOUT OF THE WATERWAY TUNNELS The two waterways tunnels are basically parallel as shown in Figure 1, with each tunnel supplying water to two units in the powerhouse. The tunnels start separated 25 meters center to center, but 250 meter from the intake the separation increases to 35 meters. The tunnels are lined with reinforced concrete until they reach the surge shafts and steel lined from there to the powerhouse. The tunnel profile is shown in Figure 2."

Jan 1, 2016

By D. A. Huggins

Column flotation is finding increasing use in the flotation of copper, molybdenum and other heavy metals and coal. Columns have proven operational, cost and metallurgical advantages which caused us to investigate their use in the proposed Escondida flowsheet. A comparative pilot plant test with 35 tons of ore showed that one column can replace three stages of cleaning and result in a significantly higher concentrate grade with no loss in recovery.

Jan 1, 1987

By K. M. Reim

Planning the development of the Quartz Hill molybdenum open pit mine in Southeast Alaska required a number of special considerations. Located in mountainous glaciated terrain, about 3.8 m (150 in.) of annual precipitation (with annual snowfall over 10.2 m (400 :in.) was a primary consideration. Mine planning included muskeg and snow removal, avalanche control, clearing timber, water quality control, dust control, seismicity, mine schedule, work force and reclamation. Quartz Hill is in an environmentally sensitive area which has required extensive environmental baseline data collection, four Environmental Impact statements (EIS) and a large number of permits.

Jan 1, 1988

By K. E. Hjelmstad

In the event of fire underground, it is essential that all miners be warned as quickly as possible. With mine air, rapidly depleted of oxygen and contaminated with smoke and toxic fire gases, any delay in the warning signal could have disastrous consequences. Unfortunately, present mine, fire warning systems, such as stench, audible or visual alarms, telephones, and messengers, are often slow, unreliable, and limited in coverage.

Jan 1, 1989

By Delbert Hamilton, Christopher Snyder

In the last three years there have been four uncontrolled heating events in mines that have been attributed to the use of polyurethane foam as a void fill product. These heating events are due to the exothermic reaction that occurs during application of these polymeric products. These events led the Mine Safety and Health Administration to issue a safety alert on polyurethane products used in void filling and ground consolidation in mining, with the goal of educating the mining community about this potential hazard. This paper provides an overview of various types of polymeric products and best practices, the factors that contributed to the heating events, and case studies involving polymeric products.

Jun 25, 2024

By K. O. Groves

Although chlorine oxidation has been found to be effective in destroying the CN ion, an excess of chlorine is needed to drive the reaction to completion. This often results in the formation of residual chloramines, which are toxic to aquatic life and often regulated by various states. The interhalogen, bromine chloride (BrCl), has been found to be just as effective but without the formation of persistent, residual chloramines. The hydrolysis and subsequent disproportionation of the highly-polar BrCl molecule essentially yields a solution of hypobromous acid (HOBr) and nonoxidizing hydrochloric acid (HC1). Studies have been carried out to directly compare the mechanism of CN destruction with chlorine and bromine chloride.

Jan 1, 1982

By W. W. Harvey

The work to be described was part of an exploratory research program directed toward identifying potentially useful but little known reactions in extractive metallurgy. In particular, the major copper sulfide minerals, as a group, have long been considered insoluble in nonoxidizing acids (e.g. Forward and Barren, 1J60; Parsons and Ingraham, 1970; Peters et al. 1972). This generalization was considered to include nonoxidizing conditions in warm aqueous MC1 solutions (Ingraham et al. 1972) and, indeed, was consistent with our own chemical and mineralogical experience. On the other hand, under hydrothermal conditions, copper and sulfide species are carried in solution and deposited as sulfides in mineralized veins. The question that poses itself is: what are the mildest conditions of temperature and fluid composition under which commercially important copper sulfide minerals can be solubilized in the absence of an oxidizing agent? A reference to H2S formation during oxygen-sulfuric acid pressure leaching (Warren, 1958) of chalcopyrite, when the oxygen partial pressure was allowed to fall, provided a clue. In the present study, experimentation with chalcopyrite concentrate in dilute hydrochloric acid, under re flux conditions (in Pyrex flasks) and with an inert purge gas, revealed substantial amounts of H2S production and iron solubilization, cite negligible copper solubilization, after 2 ½ -4 days. Under comparable conditions the extent of reaction with dilute sulfuric, acetic and phosphoric acids was markedly less.

Jan 1, 1976

By Jay Parrish

Appalachian kimberlites appear to be spatially distributed along two structure parallel trends running from Tennessee to New York. It is hypothesized that the kimberlites were emplaced at the intersection of structure parallel basement faults and cross- structural lineaments. The latter are expressed in potential field and remotely sensed data. The western trend follows the Rome Trough from eastern Kentucky to south central New York. The eastern trend parallels the edge of the Ridge and Valley in Virginia and Maryland.

Jan 1, 1984

By Don Muraoka

Soda ash, anhydrous sodium carbonate, is produced from underground trona deposits occurring in the Green River Sasin of Southwestern Wyoming. Stauffer Chemical Company of Wyoming, a jointly owned subsidiary of Stauffer Chemical Company and Rocky Mountain Energy Company mines the trona and processes it into high-purity soda ash. Stauffer Wyoming has been in operation since 1962 with a current production capacity of approximately 2.2 million tonnes (2 million short tons) per year of soda ash. The Refinery has five parallel operating trains utilizing the monohydrate process which is a series of chemical processing unit operations described below. Screening and Crushing the Trona The mined trona is brought to the surface in two counterbalancing ore skips. The ore is initially screened with Refinery feed, less than peagravel size material, entering the process while the oversize is conveyed to an outdoor stockpile.

Jan 1, 1984

By Dean R. Gehring

Creating projects to reach a goal is not new to American industry. In fact, all major construction projects, from skyscrapers to bridges, are completed using similar project management techniques. However, modern project management is relatively new. It was not formalized until 1962, when NASA and the US Department of Defense recognized the need to develop uniform project management procedures throughout the aerospace industry (Moder, Phillips and Davis, 1983). This management method was not introduced to the mining industry until the early 1970s (Britton, 1983). Project management typically follows an organized, four-stage process —definition, planning, implementation and control.

Jan 1, 1996

By A. L. Hauff

As US Coal producers are looking more and more to the international markets, they face the complex job of planning and managing transportation logistics which make effective use of production capabilities, considers the various contract requirements to be fulfilled, Train, Truck and Vessel capacities, port restraints, etc. Pulling all the necessary pieces of information together to allow proper planning throughout the supply chain is often a time consuming, manual but necessary task. This paper will discuss the various constraints, requirements and considerations to supplying coal to a global market.

Jan 1, 2012