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By R. R. Klimpel

In three recent publications, Klimpel et al (1988) and Klimpel and Hansen (1988, 89), the theory and invention process behind the identification of two new classes of sulfide mineral collectors were summarized. These two new families can be represented by the 111 generalized formulate: R1-S-R1 -NRI III (denoted as the F-series chelation family) and R-S-R or R -CHSCH-R (denoted as the S-series redox family). The influence of systematic changes in the various R groupings on laboratory batch flotation cell tests has been covered in the above references and will not be repeated in this paper. In particular, the recent article by Klimpel and Hansen (1989) should be studied as a research introduction to this paper.

Jan 1, 1989

By B. S. Van Gosen

In recent years, U.S. regulatory agencies have placed emphasis on identifying and regulating asbestos dust exposures in the mining environment, with a particular focus upon industrial mineral deposits in which asbestos occurs as an accessory mineral. Because asbestos minerals form in specific geologic environments, only certain predictable types of industrial mineral deposits can potentially host asbestos mineralization. By applying a basic knowledge of asbestos geology, the costly and time consuming efforts of asbestos monitoring and analyses can be directed towards those mineral deposit types most likely to contain asbestos mineralogy, while saving efforts on the mineral deposits that are unlikely to contain asbestos. While the vast majority of industrial mineral deposits in the Western United States are asbestos-free, there are several types that can, in some instances, host asbestos mineralization, or be closely associated with it. These industrial mineral deposits include a few types of aggregate, dimension, and decorative stone, and some deposits of chromite-nickel, magnesite, nepheline syenite, olivine, rare earth elements, talc, vermiculite, and wollastonite.

Jan 1, 2009

By Craig Ammar

JAMIE DAVIS: Our next speaker is Craig Ammar. He's director of equipment management for Cyprus Climax Metals Company. He has, prior to this assignment, been responsible for maintenance at Bagdad Copper, Cyprus' Miami smelter, and Thompson Creek. Like Jerry, he's very shy and retiring, and doesn't have any strong opinions about maintenance. INTRODUCTION CRAIG AMMAR: The ultimate goal behind implementing a proactive equipment management process is to provide capacity assurance and ultimately increase an organization's ability to generate revenue while reducing operating costs. Targeting such lofty objectives has brought many an organization to its knees, utilizing new maintenance techniques, concepts, and technology aimed at making our lives better and more organized. The root cause of such frustration generally stems from a lack of understanding or support for the fundamentals of implementing a proactive equipment management process. There are just two types of maintenance programs, reactive and proactive. It's an established fact that you need a little of both to run an effective equipment management process, obviously more of one (proactive) than the other. Here are some telltale signs that your equipment management process is in trouble: -Maintenance is performed as a knee jerk reaction when equipment fails. -Repeated and frequent equipment failures occur, with no focus on eliminating the root cause. -Sketchy, inconsistent, unclear preventive maintenance is performed or there is no support for the preventive maintenance process. -No predictive maintenance technology process is in place, or little support for predictive maintenance exists. -Less than 50 percent of your work is generated by the maintenance group resulting from inspections.

Jan 1, 1998

By Steven Tubbs

Steven Tubbs From mine to farm is a long journey for Florida's phosphate, but it is an important one to the American farmer who uses phosphate fertilizers to replenish the soil and produce the crops which eventually wind up on the American dinner table. In this phosphate-food connection, transportation plays a vital life-giving role, a role that is unique because of the large quantities of phosphate produced and the mineral's location in relation to its markets. Florida Leads World Florida is the world's largest phosphate producer, supplying 80% of the nation's and a third of the world's annual total. About 95% of Florida's phosphate goes into agricultural chemicals, with 90% going into fertilizers. Phosphate production is primarily concentrated in west central Florida, with the exception of mining and processing in north Florida by Occidental Chemical Co. The phosphate rock is beneficiated at the mine sites and then is transported out of Florida in a raw state, or to one of the industry's 18 chemical complexes where it is processed further. In 1981, Florida produced more than 42 Mt (46 million st) of phosphate rock-a 1% decrease from 1980. The industry also produced more than 12 Mt (13 million st) of phosphate chemical products in 1981 and transported them to both domestic and foreign customers. This year, the state's phosphate production and shipments are substantially lower than recent annual levels because of a depressed worldwide phosphate market. With production down slightly in 1981, shipments declined and company inventories increased dramatically. Phosphate-related shipments through the port of Tampa alone fell 20%. As a result, in 1982, phosphate operations cut production to reduce inventories. According to the Fertilizer Institute, during the fiscal year ending June 30, 1982, phosphate rock production fell 18%; phosphate rock shipments, 28%; finished fertilizer production, 30%; finished fertilizer shipments, 25%; and phosphate rock exports declined by 20%. Despite depressed conditions, Florida phosphate production and shipments are expected to increase in the near future with more rock being processed into fertilizer products. Phosphate is one of Florida's major industries. The US Bureau of Mines estimates it contributed $3 billion to the state's economy in 1981 and an additional $1.4 billion to the US economy. In addition, phosphate exports contributed to

Jan 10, 1982

By Robert P. King

In April, 1975 the Colorado School of Mines began monitoring rock mass response associated with a long- wall shield demonstration project near Raton, New Mexico. This project was sponsored by the U. S. Bureau of Mines (DOE) and performed at Kaiser Steel Corporation's York Canyon Mine. Two of the results of the intensive instrumentation effort are the empirical subsidence and horizontal strain models presented herein. These models are based on data gathered during mining three adjacent longwall panels (4N, 5N and 6N). A total of 251 permanent surveying monuments were monitored over the three-panel area. Lines of monuments were oriented along panel centerlines, perpendicular to centerlines and diagonal (45O) to centerlines. Active monuments were monitored twice a week, with less frequent monitoring of stable or slow moving monuments. Primary subsidence monitoring equipment consisted of an AGA Geometer Model 75 and a Wild T-2 Theodolite with -a Wild-Sercel DI-3S distomat.

Jan 1, 1979

By J. L. Kohler

Control circuit failures contribute significantly to continuous miner downtime. The time required to put the machine back into production is a function of the time required to diagnose the problem, obtain parts, and make the repair; of these, the diagnostic time is often the largest. A microprocessor-based system with the ability to diagnose all of the common control circuit failures was designed, installed on a continuous miner, and tested. This paper summarizes the development of the diagnostic system, and provides examples of the system's diagnostic capabilities. Implementation issues and the hardware used for the prototype are briefly described. Finally, comments on the system's performance are presented.

Jan 1, 1993

By Beverly Cramp

In 1995, mining engineer Alain Gachet thought about using Earth-observation satellite imagery to search for precious minerals. The latest radar Earth-observation satellite, Canada’s RADARSAT-1, had just been successfully launched at the time, creating new opportunities for commercial applications. Gachet was working in Congo Brazzaville as an oil executive and general secretary of Elf Congo for the French national oil company Elf Aquitaine. He understood that the RADARSAT-1 launch promised new and cost-effective sources of data for mineral and oil exploration. “It was early 1996 before I ordered my firstRADARSAT-1 satellite images,” said Gachet. “I was first struck by the quantity of information delivered by the radar images. Linear structures and faults were clearly defined and subtle topographic features were tremendously enhanced,” he said. “It was ‘tree top geology,’ but this kind of information appeared to be key for finding new gold seams.”

Jan 1, 2003

By R. C. Emmett

In extractive metallurgy, separation of insoluble solids from solutions is an important economic factor in almost all flow- sheets. This separation step can employ sedimentation, filtration (vacuum and pressure), or centrifugation. Since practically all systems require a relatively complete separation, multiple unit, countercurrent thickeners or vacuum filters are generally used.

Jan 1, 1974

By J. W. Sweeney

The .Florida land-pebble mining industry of central Florida was examined to identify trends in land use; conflicts in land use; and the effect of the conflicts on mineral resources. Many conflicts exist in the study area, such as conflicts with other users of land resources and land surface; conflicts with high revenue land users; conflicts for land surface in urban and suburban areas; and conflicting restrictions concerning utilization. Projections are made showing that lands in phosphate company ownership are expected to be made available to help meet the need for future urban expansion in the study area. Some phosphate resources have been lost due to land use conflicts, however, most of the resource loss has been small. Land use conflicts and phosphate mining are reconcilable and considerable progress toward their maximum and multiple use of land and mineral resources can be resolved through farsighted planning based on factual data.

Jan 1, 1972

Basic parameters affecting the stability of foams have been studied. We used the thin film pressure balance (TFPB) technique of Scheludko and Exerowa (1959) to measure the surface forces in foam films stabilized with various frothers such as pentanol, octanol, MIBC, and PPG. The results were compared with the froth stabilities measured using the shake tests and the film elasticity calculated using the model developed by Wang and Yoon (2006). It was found that the froth stability is controlled by both film elasticity and surface forces (or disjoining pressure), the relative contributions from each changing with frother concentration and type.

Jan 1, 2006

By Victor J. Scaravilli

This report is based on experience developed on the construction of one contract for the Buffalo, New York subway. The Buffalo subway is under construction for the Niagara Frontier Transportation Authority and is called the LRRT-Light Rail Rapid Transit or more commonly the Metro. The Initial Route of the Buffalo subway construction started early in 1979 and is scheduled for completion in May, 1984. The initial system includes 5.2 miles of underground construction, 1.3 miles at grade for a total of 6.5 miles of subway system. A total of fourteen stations, eight underground and six at grade are included on the system. The Initial Route has a planned expansion to 17.3 miles in the future. On January 15, 1979, a Joint Venture of S & M Constructors, Inc., Solon, Ohio, James McHugh Construction Co., Chicago, Illinois, and Kenny Construction Company, Wheeling, Illinois, was awarded contract 100031, the Line Tunnels from Amherst Street to South Campus in northcentral Buffalo between Delaware Park and the State University, (see Fig. 1, Location Plan) This $35,000,000.00 contract was designed by Hatch Associates Consultants, Inc., Buffalo, N.Y. The Notice to Proceed was issued January 15, 1979 and the scheduled completion date is August 18, 1981. The project consists of two parallel rock tunnels with a minimum excavated diam of 18 ft 0 in. and a final concrete lining of 16 ft 0 in. diam. The tunnels total 14,630 linear ft. In addition to the tunnels, contract C-31 includes four shafts, an underground pump station, three cross passage connections, and other minor work items. (see Fig. 2, C-31 Project Plan and Profile) The tunnels were constructed primarily within the Bertie Formation, an approximately 50 foot thick moderately fractured to massive, dolo-

Jan 1, 1981

NICOR Mineral Ventures, Inc. retained Neyer, Tiseo and Hindo, Ltd. to evaluate the potential effects of a planned dewatering operation at NICOR's proposed, 258-acre silica sand mining facility near South Rockwood, Michigan. The ?orebody? is a horizontally extensive, friable, quartz sandstone from the Sylvania Formation which also serves as an aquifer for some of the rural, residential development near the site. We conducted an aquifer test on the site which identified the important aquifer properties. Using these data and an analytical model, we determined that the radius of influence would be expected to range up to 6000 feet from the quarry during its final development stage. An inventory of water supply wells revealed that most wells had sufficient available drawdown and would not be adversely affected. A long-term groundwater monitoring program was recommended to monitor the possible effects at some of the closest wells.

Jan 1, 1987

By Virgil R. Huff, Ihor Havryluk

P. T. Pacific Nikkel Indonesia (PTPNI) was incorporated in Jakarta, Indonesia in February, 1969 by a group of Dutch and North American companies. At the same time, a Contract of Work with the Government of the Republic of Indonesia was signed, granting Pacific Nikkel all the necessary licenses and permits to explore and develop all nonradioactive minerals in two separate areas in Irian Jaya, eastern Indonesia. Nickel mineralization occurrences were confirmed by Dutch geologists in the two areas in 1952 and 1955, however, detailed exploration began in June 1969 after the Contract of Work was signed. Since that time, numerous studies and investigations have been conducted to determine the feasibility of producing metallic nickel in Irian Jaya. Four engineering studies, two bulk sample tests, an oceanographic survey, and a preliminary site investigation indicated that construction and operation of a nominal 100 million pounds per year metallic nickel plant on Gag Island were technically feasible. The fourfold increase in the price of oil in late 1973 without a corresponding adjustment in the price of nickel necessitated a reevaluation of the project, the results of which showed that the project required other conditions to be viable. Subsequently, analysis of: the future projected nickel supply-demand and cost-price relationships, the economics of treating a higher grade feed, and participation by the Government of Indonesia, indicate that the project will be viable. Therefore, planning of the Gag Island Nickel Laterite Project is continuing with the objective of commencing production to supply the market in the 1983-1984 time period.

Jan 1, 1979

By Doug Harding

The Niagara Tunnel Project (NTP) is a 10.4-km- (6.5- mile-) long, 14.4-m (47.5-ft) bored tunnel that will run under the city of Niagara Falls from the Upper Niagara River to the Sir Adam Beck power station. The completed project will enhance the capacity of the Sir Adam Beck power station by adding 500 m3 /sec (17,657 cu ft/sec) of water through the tunnel. The project uses the world?s largest hard-rock tunnel boring machine (TBM) at 14.4 m (47.5 ft) in diameter to excavate the tunnel. Features of the project include the use of a high performance (HP) main beam TBM, state-of-the-art ground support and tunnel logistics systems. A continuous conveyor is used for muck transport from the TBM to the disposal area In June 2004, the Ontario government announced that Ontario Power Generation (OPG) had been given approval to proceed with the third tunnel under the city of Niagara Falls ? the first two tunnels were constructed in the 1950s using drill-and-blast techniques. The third tunnel, appropriately named the Niagara Tunnel Project (NTP), consists of a 10.4-km- (6.5-mile-) long TBM-bored, concrete-lined tunnel with a finished diameter of 12.5 m (41.1 ft). In August 2005, OPG the selected of Strabag of Austria, one of the largest construction companies in Europe, as the contractor to build the NTP at a price of C$600 million. In September 2005, Strabag selected The Robbins Co. of Solon, OH to design, manufacture and deliver a new 14.4- m- (47.5-ft-) diameter high performance, state-of-the-art main beam hard rock TBM to be used in the excavation of the tunnel. To meet the aggressive construction schedule as requested by OPG/Strabag, the TBM needed to be sup-plied as ready-to-bore within a 12-month period after the contract was awarded to Robbins.

Jan 1, 2008

By D. M. Larsen

Since start-up in 1985 the Cannon Mine has produced and shipped a 170 g Au/tonne (5 oz Au/ton) flotation concentrate to various smelters for gold and silver recovery. Several processed have been investigated to economically produce dore' at the mine site from the refractory concentrate. This paper describes recent laboratory and pilot scale test work utilized in the process design and engineering feasibility study of a 73 tonne/day (80 ton/day) pressure oxidation and CIL facility. The designed pressure oxidation circuit utilizes a series of vertical autoclave units operating at 170°C (338"F) and 1.4 MPa (200 psig). Projected operating costs are discussed.

Jan 1, 1993

By Richard R. Klimpel

INTRODUCTION Froth flotation is the most widely used and economic means of concentrating metal sulfide ores such as those containing copper, lead, zinc, nickel, molybdenum, and pyrite. Also recoverable are other metal species that are often associated with sulfide ores such as cobalt, platinum, gold, silver, etc. Froth flotation is a physico-chemical process for separating finely ground minerals from their associated gangue material. The process involves chemical treatment of a finely divided (ground) ore in a water pulp to create conditions favorable for the attachment of certain of the mineral particles to air bubbles. The air bubbles then carry the selected minerals, called valuable, to the surface of the pulp to form a stabilized froth which is removed and recovered. The unattached gangue material remains submerged in the pulp and is either discarded or reprocessed. To obtain the adherence of the desired mineral particles to the air bubbles, at least two specific steps must occur: a hydrophobic (water hating) surface film must be formed on the particles to be floated along with a hydrophillic (water wetting) film on all other particles; and a controlled bubble surface tension interface must be maintained, allowing for high particlelbubble collision frequency and efficient attachment or sticking of the particle to the bubble once collision has taken place. In most flotation applications, the above two steps are controlled by chemical flotation reagents. The collector is a chemical reagent which produces the hydrophobic film on the valuable mineral particle and is the primary driving force that initiates the flotation process. The frother is a chemical reagent which influences the collision frequency and attachment efficiency of hydrophobic particles and air bubbles. Thousands of research papers and books have been published on the chemical theory behind sulfide mineral collectors, e.g., Fuerstenau (1962), Fuerstenau (1976), Fuerstenau, et. al. (1985), King (1982), Leja (1982) and Moudgil and Somasundaran (1987), This article will only address and summarize some of the more practical aspects of collector usage. The industrial scale practice of froth flotation in sulfide mineral concentration has changed little since the 1950's. For example, of the approximately 80,000 metric tons of sulfide mineral collectors used commercially (1980) in the free world, almost 98% were known and manufactured in some form 25 years ago. A very interesting and informative history of collector development has been given by Crozier (1984). In addition, the industrial scale practice of froth flotation applied to sulfide ores has proceeded since the 1920's with often little direct (predictive) scientific explanation due to the extreme complexity of the flotation process. Empirical testing has been a mainstay of industrial flotation reagent development and use. Even today there is often strong disagreement between researchers as to the mechanisms of chemical flotation practices that have been performed successfully at an industrial scale for many years. As a result of the above environment which makes reagent cost/performance analysis difficult for new reagents, there is a strong tendency for the flotation operation to use, and reagent companies to supply, as cheap as possible raw materials and manufactured products that are quite general in application. In the last 20 years or so, there has been increasing technical effort to tailor make reagents for specific applications, but to date such work has had little commercial impact. It is clearly the hope of this author and others that this situation will change in future years as technology improves and pressure for improved flotation performance intensifies. This article is a condensation of collector usage trends quantified as part of a comprehensive industrially oriented applications program on froth flotation organized by Klimpel and coworkers (1979-1987) and as reported in various countries that participated in the program from 1978-1983. No attempt will be made to provide specific.

Jan 1, 1986

By W. G. Pariseau

A study of coal pillar strength was done at the Beehive Mine during a three year period, 1974?1977, in a cooperative effort involving the University of Utah, RE/SPEC, Inc., and the American Coal Company (Pariseau et al, 1977). The Beehive Mine is located in the Wasatch Plateau coal field in central Utah near Orangeville, Utah, where mines are developed from outcrops between steep canyon walls with topographic relief of a kilometer or so (3,600 ft). Coal is found in Cretaceous sediments that dip gently to the west. Detailed geology of the Wasatch Plateau is described by Doelling (1972). Mining was done in the Blind Canyon seam. An earlier Deseret Mine worked the Hiawatha seam that is lower in the stratigraphic column by about 36 m (120 ft). Mining progress and ownership changes occurred in time with mine mergers and name changes eventually to the collective Des-Bee-Dove label. At the Beehive Mine, depth varied with topography but was approximately 360 m (1200 ft) on average; seam thickness varied from 1.5 to 6 m (5 to 20 ft) and usually required two passes of the miner. The mine was eventually closed and finally reclaimed in 2003. Semborski and Oakley (2006) present a brief history of the mine and describe the reclamation work in some detail. Figure 1 shows the surface topography in the vicinity of the mine that is in the center of the figure.

Feb 23, 2014

By Jai-Woon Moon, Wonnyon Kim

Deep-sea hydrothermal vents (hereafter chimneys) are commonly found on the new crust forming along divergent plate boundaries. Related to the chimney cycle from birth to death, it is hard to define the growth stage of the chimney due to a brief life span of the venting hydrothermal plume. Here we try to categorize the mineral magnetic properties of the chimneys according to their venting fluid-temperatures. Hydrothermal sulfide deposits in the Southwest Pacific were explored in 2012 and chimneys were collected using remotely operated vehicle (ROV) and Grab with AV camera (GTV). In the present study, mineral magnetic properties of three Cu-rich chimneys were measured: a high-temperature chimney showing a venting fluid-temperature of about 200°C (ROV01); a lowtemperature chimney of about 80°C (GTV01); and an inactive chimney (ROV02). The chimneys were sliced to ~1 cm intervals from core to outer margin. Magnetic properties of ROV01 are dominated by pyrrhotite, except for the most outer part that experienced severe oxidation. Concentration and grain-size of pyrrhotite are relatively low and fine respectively. In the GTV01, pyrrhotite, dominant in the core, is gradually mixed with hematite toward the outer margin of the chimney due to secondary oxidation. Both the concentration and grain-size of the magnetic minerals are greater compared to the GTV01. High concentration and large grain-size of magnetic minerals characterize ROV02. Dominant magnetic phases are pyrrhotite, hematite, and goethite. In particular, the most outer margin shows the presence of magnetite produced possibly by magnetotactic bacterial activity. Such distinctive contrast in magnetic concentration, grain-size, and mineralogy among three different types of chimneys enables the life stage of the Cu-rich chimneys to be determined through a mineral magnetic study.

Sep 1, 2014

To simplify programming, image analyzers commonly measure either linear intercepts or the areas of particles and grains to determine liberation based on polished section mounts. However, the concentration of minerals by flotation is based on reagents that interact with the exposed surfaces of the minerals. Thus, it is often perceived that image analyzers should measure the perimeter of the mineral of interest in the ore particles. A comparative liberation study of thirteen samples collected from a flotation plant processing a complex base metal sulfide ore showed that the liberation of the ore minerals determined by area measurements is very similar to the liberation determined by the exposed perimeters. The liberation determined by exposed perimeters is more appropriate only for those cases where the mineral texture is so complex that it is retained in the small particles generated in conventional grinding operations.

Jan 1, 2002

By D. F. Scott

The purpose of this study was to determine if miners are at risk from exposures to chemicals used in the mining industry, and determine the nature and sources of the illnesses and injuries. The authors reviewed the Mine Safety and Health Administration?s (MSHA) Employment and Accident, Injury, and Illness database and identified 2,705 cases of chemical-related injuries and illnesses that were reported to MSHA from 1999-2006, involving 66 different chemicals. The main source (cause) of chemical-related cases was acids/alkalis (about 39%). The primary nature (effect) of chemical-related cases was chemical burns (about 57%). The job classification where workers incurred the most chemical-related injuries and illnesses was cleaning plant operator/media operator/boney preparation plant operator/crusher worker. The number of nonfatal days lost did not change significantly and overall, the incidence rate of chemical-related cases decreased by 36%. Chemical burns accounted for a large number of injuries; mining companies should carefully examine their personal protective equipment (PPE) requirements, training methods, and safety culture to insure that their workers are protected.

Jan 1, 2009