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By Bayard Morrow

THE copper-bearing ores concentrated at the Anaconda plant of the Anaconda Copper Mining Co. are principally a mixture of copper and iron sulfides associated in a gangue consisting of quartz, lightly altered granite and feldspars, with sphalerite and galena and more rarely barite and hubnerite as accessory minerals. The predominant sulfide is pyrite. The copper minerals present are: chalcocite, bornite (Erubescite), enargite, chalcopyrite, covellite, tetrahedrite and some tennantite. Normal concentrator practice removes a slime prior to ball-mill grinding. The deslimed ore is ground to approximately 10 per cent plus 65 mesh for flotation. Two selective flotation circuits are used, one for deslimed ore and one for slime. The metallurgical results obtained are shown in Table 1.

Jan 1, 1933

By Milton E. Wadsworth, Edward M. Eyring

Better understanding of solid surfaces and their associated adsorption products is of both academic and practical value. The study of detergents and their behavior in cleaning surfaces is fundamentally related to the nature of the products adsorbed and their ability to compete for certain surfaces. Similarly in flotation, the nature of the adsorbate before and after adsorption is basic to clear understanding of the process. The recently developed pellet technique employing infrared spectroscopy provides a powerful tool for the study of solid surfaces. Absorption bands, which are infrared-active, may be observed for adsorbed products. Also any changes in the surface substrate that occur as a result of adsorption may be detected by means of differential spectra

May 1, 1956

By C. Maltesh, P. Somasundaran

The ever increasing need for treating fine complex mineral bodies has led to the evolution and rapid development of advanced processing techniques for fine grinding, classification an if mineral separation and purification. With the introduction of these new technologies and understanding of underlying fundamental principles, mineral processing is now being applied to materials ranging from ceramics and composites to superconductors. In this review, current and potential applications of mineral engineering techniques to advanced materials processing are discussed. Particularly, material processing involving ultrafine grinding, dispersion and flocculation and thin film formation is examined. Novel techniques of solid/liquid separation involving manipulation of interfaces and use of high intensity high gradient superconductor magnetic equipment for solid/solid separation are discussed.

Jan 1, 1990

Kaiser Sees Bright Future for Jamaica Kaiser Aluminum Co. has a big stake in the British West Indies, the Island of Jamaica in particular. There, Kaiser is busy developing one of the most promising bauxite finds in recent years. The $12 million operation was officially opened in February. Facilities have a rating of an annual capacity of 2 million tons and will supply Kaiser plants with ore for years. The ore comes across the Gulf of Mexico, up the Mississippi to stockpiles at Baton Rouge. The stockpile at Baton Rouge would throw many an old river boat skipper for a loss. Where no mountain once existed now stands a man-made bluff of bauxite, known as Bauxite Peak.

Jan 6, 1953

By W. Dalmijn, H. de Ruiter

"The decline in students for mining and metallurgical engineering in the last few years has lead to the closure of many university departments in all first world countries around the world. Three independent studies carried out in Europe, Australia and North America indicate that during the next decade the demand for mining, minerals processing and metallurgical engineers will be significantly higher than the supply. Demand for engineers will increase even more because many of the professionals in industry are about to retire within the next 5 years. Meanwhile mining is a growth industry, minerals demand continues to increase in line with the growth in World GDP, as illustrated in the Graph at the end of the paper."

Jan 1, 2005

By Eric K. Albert

The permit generation and review process represents both a time consuming and expensive task for industry and government alike. Changes in regulations and in review procedures cause additional delays. This leads to potentially higher costs of doing business and the extension of time for a project to lie started. This paper describes the motivation and methodology of applying an expert system to function in the role of a permit reviewer. The problems of representing the knowledge of the reviewer and regulatory criteria are illustrated. Futhermore, the selection method for the expert system shell is addressed. Finally, a sample review is demonstrated to show the results of applying this artificial intelligence method to the process of permit review.

Jan 1, 1989

By Kenneth S. Graham, S. C. Gambrell

A short term, simple roof bolt load cell which uses a birefringent (photoelastic) coating as its sensing element has been developed. The load cell is installed between the bearing plate and the nut/washer and measures the initial force after installation by the bolting machine. The load cell can be removed from the bolt and used again to measure initial force in another bolt if desired. Because temperature and humidity changes in the mine cause creep/relaxation of the coating and/or adhesive, the load cell is useful for accurately measuring force for a period of only two weeks after installation. Force in the bolt is determined by referring to a calibration curve for the load cell.

Jan 1, 1992

Although giant strides have been made in the Australian mineral industry over the past quarter of a century in terms of mineral discoveries, self-sufficiency of commodities, contributions to exports and other aspects, there are unhealthy signs emerging which require attention. For instance there are 20 out of 34 discoveries of base metals, uranium and nickel which for a number of reasons await development. Some of the reasons for the standstill in the mineral industry are partly economic, partly due to competing land use, uncertainty in applying or, recognising the principle of crown ownership of minerals, and to some extent lack of appreciation of two closely related exploration activities referred to as development exploration and assessment Exploration.

Jan 1, 1979

By Raphael Mourad, Colin R. Phillips

Investigation of the traps in LiF:Mg, a multi-peak phosphor, was carried out using simple phosphorescence decay analysis. Half lives at room temperature of the trapping centres (peaks -lb, -la, -1, 0, 1, 2, 3a and 3) in the phosphor after irradiation with [a] radiation were found to be 3 s, 5 s, 28 s, 4 min, 15 min, 1 h, 6 h and 2 d respectively. Justification for the method of analysis is pro- vided and the results of measurements compared with published data. The effects of pre-annealing at 400°C for 1 h and 80°C for 24 h on the trapping configuration and on the trapping efficiencies were also studied.

Jan 1, 1981

A simple and rapid method for delennining gold and silver in carbon samples is described. The method involves dissolution of carbon ash in a strong oxidising medium of aqua regia and hydrofluoric acid. Gold and silver are determined in the resultant solution using atomic absorption speetrometry (AAS). The method is efficient and reproducible. Gold results are comparable to the standard fire assay results, with agreement of results within ± 5 per cent. The co-efficients of variation for gold and silver are 0.37 and 0.39 per cent respectively for six replicate analyses. The analysis of gold and silver in a batch of ten carbon samples can be completed in approximately four hours.

Jan 1, 1992

By A. F. Meger

REPRESENTED here are the ideas and varied experiences of many people in the Hanna Coal Co. who have helped develop, over a number of years, an efficient and flexible method for spraying con- trolled amounts of oil on coal. Since the George- town preparation plant began operations early in 1951, oil treatment of coal has received special attention. It is believed that oil treating will satisfy present customers and also attract new markets. The first step in developing the new method of oil spraying was the construction of a dust cabinet for testing 50-lb samples of treated coal with the available oil sprays on the market. Tests results were tabulated for both indoor and outdoor storage.

Jan 7, 1954

By M. J. Hart, E. C. McDowell

There are no formulas that guarantee success when obtaining zoning approval for mineral aggregate mining. Local land use decisions often represent the most controversial issues faced by a community. Public awareness, concern, willingness to get involved, sensitivity to the environment and, probably most important, fear of change only begin to describe the atmosphere in which local land use decisions are made. The public hearing process is quasi judicial, adversarial, and unfortunately, not designed for resolution of disputes. It is not difficult to see the need for an alternative to present methods. Hopefully, some day there will be a process that will do away with or at least minimize unnecessary, unproductive, and unmanageable community conflicts.

Jan 1, 1986

By D. O. Rausch

The economic relationship between steepening slopes and decreasing waste removal requirements ahead of ore mining is one of the most important factors in the design of open-pit mines. The steepness and stability of the pit slopes often spells the difference between ore and waste profit or loss in low cost open-pit operations. Unfortunately, the technology necessary for designing stable rock slopes is still in the early stages of development. Past and current pit-design methods have been, and still are, empirical, with rock slopes frequently made too steep or too shallow. As such, large expenditures are often made for correcting slopes after failures occur, or for unnecessarily removing more waste material than required.

Jan 6, 1965

By I. Dumitrescu

Since 1990, the entire Romanian mining industry has suffered a major restructuring, i.e. technical and economic. The large majority of the remaining active mines are these with a chance for economic comeback. This is also the case for the mines that belong to MINVEST Deva Company; most of the mines are closed, and are waiting to be reclaimed. The authors present the closing procedures of the former copper mining perimeters managed by MINVEST. It is well known that pollutants of concern for the environment must be monitored to obtain reliable information on the quality of ambient conditions and to minimize their impact on the environment. Consequently, the monitoring problems during the closing procedures will be presented.

Jan 1, 2008

By Dieter Froelich, Giles Turcotte

In the near future, Bong Mining Company (BMC) will start mining a new deposit known as Zaweah II which is a narrow iron orebody requiring multiple row blasts with the bench floor as a free face. This called for the development of a new blasting technique. The article delineates the problem and its restrictions related to blasting. It also describes the approach which was taken for developing this new blasting technique which is essentially an application of the cratering theory with near spherical charges. Basic crater tests were conducted using various combinations of hole sizes, explosive strengths and delay patterns. From the results obtained, several alternatives were considered for production blasts and the most promising ones were evaluated.

Jan 1, 1980

By M. J. Shulman

An algorithm used by the US Coast Guard to find lost objects is utilized to optimally allocate exploration efforts during initial stages of an exploration program. Based on classical search theory, the algorithm assumes a target probability distribution function, a detection function, and a cost function. The three functions are analogous to delineating areas of possible mineralization, choice of exploration methods, and exploration budget. Application of the algorithm is shown for a hypothetical target distribution. Using the maximum number of field day available as the cost function, the optimal allocation of effort is shown for different exploration methods, e.g. electromagnetic survey and induced polarization. The adaption of the algorithm for the exploration process is discussed.

Jan 1, 1984

By Barry K. Johnston, Norman W. Bainbridge, Neville C. Lockhart

CSIRO and its collaborators have developed a major R & D project on dewatering of coal. This involves sub-projects on (i) the fundamentals of coal-water associations; (ii) reducing the variability of product moisture levels from small coal centrifuges; (iii) process mechanisms and optimisation for fine coal dewatering; (iv) pilot scale testing, engineering development and innovation. Results from each of these sub-projects are presented, and the pilot facility incorporating a vacuum filter, belt press, membrane press, hyperbaric filters and centrifuges, is discussed. The vacuum filter and membrane press can be configured for electric-field assisted dewatering, which provides substantial enhancements in the rate and degree of dewatering for fine coal, coal tailings, and other suspensions.

Jan 1, 1995

By M. J. Laurila

Utilizing data compiled from a drilling program and bulk samples taken from a coal reserve, flowsheet performance for a coal preparation plant can be calculated using a desktop computer. Sets of equations defining material balances involving coal preparation plant unit operations are employed to depict plant performance. Techniques are discussed for interpolating washability data and extrapolating size distributions and other critical data to expand on oftentimes limited sets of quality data to a useable data base from which projections can be made. Simulation of flowsheets can be done for a number of different conditions and configurations while still remaining in a limited working memory capacity of 32,000 bytes. Presented within this paper are several pertinent examples.

Jan 1, 1982

By Arthur F. Colombo, David M. Hopstock

The Lake Superior region contains extensive deposits of potential iron ore in the form of fine-grained oxidized taconite. To help assure utilization of this resource in an environmentally sound manner, the U.S. Department of the Interior, Bureau of Mines, is conducting bench- and pilot-scale research using wet high-intensity magnetic (WHIM) separation. The advantages and disadvantages of WHIM separation in comparison with other feasible beneficiation methods are discussed. Pilot plant results are given for a flowsheet in which WHIM scavenging is used in conjunction with selective flocculation and flotation. A mathematical model for use in process optimization is given. Practical aspects of matrix selection and separator design for WHIM separation of fine particles are discussed.

Jan 1, 1980

By Harry Dobroski, Larry G. Stolarczyk

A medium-frequency (MF) communication system has been built and has been tested in underground mines. It provides radio coverage to vehicles and personnel anywhere in the mine via parasitic coupling into existing mine conductors. The system consists of base stations, repeaters, and vehicular and personnel transceivers. Air-core antennas for vehicles and clamp-on antennas for base stations and repeaters were designed for maximum coupling efficiency using existing mine wiring. Personnel transceivers are of a unique vest design that features a low physical profile, good user comfort, and efficient antenna design. In-mine tests show impressive results. Range between rubber-tired vehicles and base stations is often measured in miles. With repeaters, greater range is possible.