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By C. L. Schaidle

Computers and communications technology have revolutionized many industries. In earthmoving, this revolution has just begun. The major changes are still to come, but they are just around the corner. This paper presents a vision of this up-coming revolution in our industry. This vision is comprehensive. It includes basic communication, machine monitoring and diagnostics, job and business management, planning and operations, and machine control. For our industry to realize maximum benefits from the information age, we must have a vision of the future that is shared by technologists, machinery producers, and miners.

Jan 1, 1994

By C. M. Bartley

In world-wide mining circles countries become known by the principal minerals they produce. The production of iron, copper, phosphate and sulphur in the United-States-has-been particularly significant and has provided the base for aggressive developments in heavy industry, agriculture and chemicals. Mention diamonds and gold-and you will think--South Africa; silver-Mexico; nickel and asbestos--Canada. The main purpose of this paper is to point out that potash mast be added to the list of minerals by which Canada is known in the mining World. The potash deposits of western Canada must be classed as a major world source of chemical fertilizer raw material. We believe that they are both the largest and the richest of all known deposits in the world. The most knowledgeable people in the industry avoid making estimates of reserves because even where the arithmetic is correct the total is so large that it appears to be ridiculous. In 1957 Marion Goudie made a carefully qualified estimate of 6 billion tons of recoverable potash above 3,500 ft, and grading 25 per cent K20 or better. This figure can now be increased by the amounts available through solution mining. No one has bothered to estimate how much this is because it is so large that the actual amount is not significant.

Jan 1, 1966

By Shibayama A.

In this research, an investigation of a process to selectively remove arsenic (As) and antimony (Sb) contained in enargite (Cu3AsS4) and tennantite/tetrahedrite ((Cu1,Fe)12(As,Sb)4S13) copper resources by leaching and precipitation were performed. First in the leaching process, the target was to selectively leach As/Sb and reduce their contents in the ores to <0.5 wt% followed by a second process to remove As/Sb dissolved in solution for environmental control. Enargite ore contained 3.65 wt% As while tennantite/tetrahedrite ore contained 5.40 wt% As and 4.85 wt% Sb. Alkaline leaching using NaHS?NaOH media at varying experimental conditions (temperature, pulp density, time, reagent concentrations) were performed to investigate the process. As/Sb precipitation studies were also performed to control high As/Sb concentrations in leach solutions by using elemental sulphur (So). Results from leaching studies showed that over 99% of As/Sb in the impure copper ores can be removed and their contents in the final solids reduced to <0.5 wt%. It was also established that such very high leaching could be achieved at 80°C within 1?6 h and pulp densities as high as 1000 g/L. The study also revealed that leach solution containing very high As/Sb concentration ranging from 5 to 20 g/L can be used as fresh solution for leaching of fresh ores until concentrations exceeding 35 g/L when it was sent to precipitation circuit for As/Sb removal. Addition of elemental sulphur at 90°C and fast cooling to 30°C allowed over 60% As/Sb precipitation and removed as Na3AsS4 and solution with reduced As/Sb concentration to leaching circuit for continuous use. Keywords: Enargite; Tennantite/Tetrahedrite; Selective Leaching; Precipitation; Sodium hydrosulfide;

Sep 1, 2012

By D. C. Foote

MR. FOOTE: This paper deals with blasting and mechanical loading. The Union Pacific Coal Company does all of its blasting with permissible powder and electric shooting, but this paper deals principally with blasting in connection with mechanical loading. With the introduction of mechanical loading into the coal fields of southern Wyoming one of the main problems to be taken into consideration was the drilling and blasting of the coal. The methods used in blasting coal for hand loading were found to be ill adapted to the mechanical practice, so numerous tests were conducted from time to time to determine a system or systems whereby the coal might be blasted in a form to be easily handled by the loading units. The general practice in blasting coal for hand loading, for example in a room 24 feet wide and seven feet high with an undercut of seven feet, would be to shoot one or two strong breaking shots in the center and one on each rib. While much of the cut would be blasted down in good lump, some coal would be left hanging at the back and ribs. With hand loading, the miners would have time to pull this coal down with a pick between cars and eventually would clean up the place ready for the cutting machine. The loading machine, however, cannot get this coal down and its operation would be delayed while the men were doing the necessary pick work.

Jan 1, 1929

The relevance of borehole and bore core evaluation to the design of underground coal mines is illustrated by considering the technical parameters of colliery design and the information from which they are constructed. The nature of this information is described, together with some methods for its storage, processing and presentation. Geophysical exploration techniques are compared as information sources. It is concluded that borehole and bore core evaluation is relevant and necessary for colliery design, but that optimum results will be obtained if drilling can be combined with geophysical techniques. Because of the inherent uncertainties in prediction of mining conditions the necessity of obtaining as much information as practicable from drilling evaluation is also stressed.

Jan 1, 1977

By G. Mihaylov

The basic principles of systems analysis are presented. A model has been designed to determine the location of the Main opening in the presence of three or more stock orebodies. The necessary condition is to find a location for the Collection point which is an essential element in opening up each orebody (stock). The model takes into account the total transportation costs from each orebody to the collection point. Three variants are considered provided that the orefield is divided into two levels at least: - a collection point is designed at every level; - a collection point is designed at the lowest level, i.e. where the so-called concentration level is formed; - the collection point is located at a point between the planes of the two levels; The effect of the depth of mining and mine output on determining the method of opening up the orefield has been analyzed by considering a vertical and/or an inclined shaft. A function has been constructed which allows for investigating in both a static and dynamic regime the capital costs for constructing the whole complex including the shaft. The character of the function does not allow finding the global limits. Therefore, it is of particular importance to specify the limiting conditions. In this case these are the flow capacity of development openings and the shaft. The basic groups of cost and natural indicators for assessing and selecting an optimal technological solution have been systematized. The combined analysis of the two approaches to finding the location of the Main opening and determining the mining method enables us to determine when an inclined shaft is best, and the depth at which opening by a vertical shaft has no alternative. Thus, a transition area is formed for which the selection of an optimal technological solution requires an analysis similar to that proposed in this paper. Conclusions are finally drawn which serve as a basis for determining the areas of application of each opening, including the use of a combined scheme of mine opening. The approach presented can be used in both investigating the possibilities for opening up new orefields and reconstructing existing ones in cases when the mining operations go deeper.

Aug 1, 2013

By John E. Miller

In recent years there has been increasing concern in the mining industry over the availability and high cost of diesel fuel to support mining operations. Unit Rig & Equipment Co. has been deeply involved with the development and testing of the newest designs for trolley assist. Beginning in dune 1980, Unit Rig modified and commissioned six 156 metric ton (170 short ton) trolley assist haulage trucks at two mine locations in South Africa. Operating haulage trucks with General Electric GTA 15E/776 drive systems were chosen for the tests since this size of truck represented the majority of the population of large size haulage trucks and the greatest technical development problems. Test operations have proven the feasibility of equipment designs in actual operation and preliminary economic data has convinced the operators to proceed with planning to modify their entire mining operation to use trolley assist. The initial capital investment incurred for trolley assist can be recovered in a short period of time. Following this quick capital recovery, mines will continue to realize lower operating costs through increased productivity and lower diesel consumption.

Jan 1, 1980

By John W. Straton

Following the completion of the paper presented in February, 1972, data were received from many other mines and some original respondents submitted more complete questionnaires. The computer program was changed to permit the results to reflect more clearly all the data reported by the mines. The original paper was revised to reflect the new information. There were significant changes in some numerical values, particularly where the size of the sample changed appreciably. Some limited samples considered originally in arriving at conclusions were not relied on in this revision. The revised tables and text are of the same design and format as the original paper.

Jan 1, 1972

By B. W. Lee, P. O?Shaughnessy

The practice of manganese ferroalloy smelting has traditionally been based on utilising oxide ores which typically contain a high level of manganese. This preference for oxides has even been extended to the modification of natural carbonates into nodulized oxides. However smelting practices developed over the past 30 years have created a market for natural manganese carbonate ores, driven in part by the unique properties that this type of ore can offer. An understanding of the mineralogy of carbonate ore and its thermal properties has provided important information which enables furnace operators to take full advantage of the chemical differences. However changes to traditional operating practices have been necessary. Once furnace operations using natural and unmodified carbonate ore have been mastered, the unique chemical features of manganese carbonate ore are able to contribute, not only to new product development, but also to cost savings. The use of natural manganese carbonate ore is now a well-established aspect of the industry. The sustained increase in demand for carbonate ore worldwide over the past several years confirms acceptance of its quality. There are effectively few limits to its successful use.

Jan 1, 2004

By K. Niboucha, M. Zergoug, S. Brick-Chaouch, H. Houali

"Corrosion is an electrochemical process that causes degradation and deterioration of various steel works (pipelines, drains, cisterns) whether they are buried, immersed, or not. Worldwide, we estimate that corrosion destroys a quarter of the annual production of steel at a rate of 5 tons per second. Several techniques are used to protect against corrosion. Among these processes, Cathodic protection, which is regarded as the best technique to assure the protection of steel, works against this phenomenon. This is achieved either by a system of reactive anodes, or by the technique of impressed current protection or other techniques. Before any installation of cathodic protection, a preliminary study and pre-evaluation of certain parameters must be made. In the present work, we will present an example of dimensioning of an installation of cathodic protection by imposed current of a pipeline using solar energy, where we discuss the following items:•,Evolutions of the potential as well as current along the pipeline and their respective expressions deduced from the laws known as telegraphists;•,Range of protection (potential of protection along the pipeline);•,Influence of the isolation resistance of the coating on the range of protection;•,Effect of the aging of the coating and its influence on the current of protection."

Jan 1, 2005

By Fernando Zúñiga y Rivero

El presente texto describe los principales métodos usados en las etapas de prospección por petróleo para así establecer la inversión en la búsqueda de petróleo. La exploración de petróleo es una de las más riesgosas dado que los estudios geológicos previos a la zona, no siempre se corresponden las espectativas de la inversión. Pese a estos inconvenientes, el petróleo se sigue consolidando como la principal fuente de energía del país, tanto por su Es bajo costo, poder calorífico y las ventajas para el transporte y manipuleo. De forma que la provisión de productos de petróleo, como su abastecimiento nunca ha representado un problema en el país, sobrepasando los 15 000, 000 barriles de petróleo hacia 1958. De otro lado, el circuito de prospección de petróleo comprende la roca reservorio, la roca madre y la roca sello, cuya acumulación de capas genera irregularidades y forma las trampas petrolíferas. Reunida estas condiciones para la acumulación de petróleo, hay posibilidades de que la zona a explorar contenga algún yacimiento petrolífero. Sin embargo, existen casos donde se hay una superposición de estratos a manera de reservorio que ocultan la posibilidad de un yacimiento, como es el caso del desierto de Sechura o la montaña del Perú. En estos casos, se emplea los métodos geofísicos de prospección que verifican el indicio de las condiciones estructurales del subsuelo. Entre los distintos métodos utilizados, tenemos a los gravimétricos, basados en la medición de variaciones de la atracción de la gravedad sobre la superficie de la tierra; los métodos magnéticos, que miden las variaciones del campo magnético terrestre, generados por las propiedades magnéticas anómalas del subsuelo; los métodos sísmicos que son los más usados dado que informan de forma precisa sobre la condición geológica del subsuelo, y los métodos eléctricos, que son los menos usados puesto que otorgan datos superficiales sobre las condiciones geológicas del subsuelo. Finalmente, para el costo de exploración del petróleo se tiene que equilibrar los siguientes factores: los métodos de prospección, costo de materiales y equipo, sueldos del personal, número de puntos de observación, facilidades de transporte y las clases de terreno y clima.

Jul 20, 1959

By David De Lemos Pires

Mining is essentially a materials management process where materials are classified, excavated, moved to a desired location, processed at a cost and sold for a price hopefully to generate a profit. ?How much is that cost and can it be reduced?? is the age-old question. The requirement for a paradigm shift with regard to materials movement in search of low-cost production has not just happened by chance but, rather, has been driven by agents of change that include mining companies, consultants, governments and equipment suppliers. During the past 100 years of mining, surface mining technology has involved humans with hand tools, humans with machinery and unmanned automated equipment. In the past 50 years, surface mining technology has evolved and now takes the form of trucks and loaders (TL), in-pit-crushing conveying (IPCC) and autonomous haulage equipment (AHS).

Dec 1, 2013

By C. Otto Walls

Six years after the start of gold heap leaching at Smoky Valley Mining, Round Mountain, Nevada, three areas of process improvements are examined to show how productivity was increased. Original design concepts and practices are reviewed in order to compare to current methods. The evolution of change in heap mainterance is also reviewed.

Jan 1, 1984

By G. L. Gates

Five possible sources of water for waterflooding of petroleum reservoirs in the arid San Joaquin Valley of California were considered. Three of them (water produced with petroleum, water from a shallow saline aquifer, and waste irrigation water) were analyzed chemically; laboratory information for one (sea water) had been developed during a previous study. A series of laboratory tests made on the fifth source (fresh water) determined the solubility of calcium sulfate dihydrate in water. Laboratory analyses included the following: Chemical analyses of water produced with petroleum and waste irrigation water; solubility of calcium sulfate dihydrate in water and brines; the effect of excess sulfate on the solubility of calcium sulfate in brines; the presence of sulfate-reducing bacteria; and the permeability of cores from a petroleum reservoir to air, to water from other petroleum reservoirs, and to waste irrigation water. The results showed that most of the waters and mixtures of waters are compatible with petroleum reservoir waters and are generally suitable for injection. The calcium content of some of the formation waters is quite high, and care must be taken to prevent precipitation of calcium sulfate dihydrate. The permeability of the few cores tested was about the same to water and brines as to air, indicating that formation damage due to clay swelling will not be serious. The waters most likely to be available for injection are water produced with petroleum, water from shallow saline aquifers, and waste irrigation water.

Jan 1, 1970

By Deepak Malhotra

Western technology is considered a panacea for all ills in developing countries. Is that really the case? Are inventors of new technology overselling? What are the expectations of the receiving party? The author offers his views on these questions and proposes a process for systematic transfer of technology while minimizing surprises on the part of the seller and the receiver.

Jan 1, 2001

By Eugene C. Robertson

INTRODUCTION A direct proportionality between the observed displacement of a fault and its thickness of breccia and gouge has been proposed recently (Robertson, in press). To validate this finding, an explanation of the mechanics of continuous breccia formation is needed and is offered in this paper. A summary of evidence for the finding will show why an explanation is needed. The correlation between fault displacement [d] and accompanying breccia- plus-gouge thickness [t] seems to be linear and reasonably well established over 6 orders of magnitude, with a range in [d] from 1 mm to 1 km, on a trend of [d/t]= 100, shown in Figure 1. Most of the points are for faults observed underground in mines. The [d] – [t] relation is limited to normal and reverse faults, that have a flat to steep dip and a displacement less than 5 km. It is not applied to large strike-slip and low-angle overthrust faults, whose displacements and breccia thicknesses are widely variable and uncertain. Undisplaced jointed rock is not included in the thickness measurement. A complete description of sources and analysis of the data is given in Robertson (in press). One would intuitively expect that continued movement on a fault would grind up the previously formed breccia and gouge and not produce any more, but the evidence (Fig. 1) indicates otherwise. A physical model to explain continuous formation of gouge and breccia from the wall rocks can be obtained from laboratory experiments on friction.

Jan 1, 1982

EMMES Sampling Conference BACKGROUND & INTRODUCTION ?Impala acquires toll material to supplement production from ROM ?Toll material consists of filter cake, slurry and catalysts ?Samples are collected to determine the commercial values of the lots ?Slurry deliveries projected to remain relatively constant at 120tons dry solids per month, whereas filter cake deliveries set to increase five-fold to 800 tons dry solids per month ?Due to projected increase in toll material, new sampling and offloading facility presently under construction at Impala ?Presentation will cover two projects aimed at reducing the uncertainty associated with sampling of toll deliveries ?i.e. slurries and filter cake.

Jan 1, 2005

By A Logan, B Cuthbert

Brown and Chitombo (2007) indicated that during the last two decades, the international mining industry has been using mainly mass mining methods to extract safely and economically some of the important commodities such as copper, diamonds, gold, iron and nickel. Mass mining may be implemented either on the surface through large open pits or underground using mining methods such as sublevel, block and panel caving. Developments in the last ten years have demonstrated that caving methods can be applied successfully in strong orebodies at greater depths and in increasingly challenging geotechnical environments for which more traditional mining methods would be unsuitable, unsafe and/or uneconomic. These underground mass mining challenges require æfront endÆ investigation and analysis, robust engineering design and disciplined implementation and operation. Newcrest Mining Limited has focused its efforts on the development of gold/copper projects of substantial scale and margin. To help achieve this, the company is applying and further developing mass mining methods. These include large-scale open pits (OP) and underground mining methods such as sublevel (SLC), block (BC) and panel caving (PC). Block and panel caving now offer economies of scale opportunities for Newcrest to achieve high production rates at lower production costs; thus enabling the exploitation of mineral endowments at higher margins. This paper discusses the practical aspects of caving technologies that Newcrest continues to develop through its expertise at Telfer and Ridgeway SLC operations, Ridgeway Deeps BC and Cadia East PC projects.

Jan 1, 2008

By Hayes J. A

The satisfactory ventilation of an extensive coal mine is a subject which requires continual attention from all concerned.It must be remembered that a colliery contains many miles of workings, extending in all directions and throughout which noxious gases may be given off either naturally or by oxidation of the coal; fumes from explosives will be produced, dust will be gathered and carried in suspension, and water will be evaporated, producing a high humidity. Hence a considerable quantity of air in movement must be available to provide sufficient oxygen for men and horses, as well as to dilute and sweep away impurities, and maintain a tolerable degree of coolness.To maintain these conditions a modern colliery is divided up from the main ventilation shafts or adits (as the case may be) into a system of main airways, and in the working districts is further subdivided into district splits. To initiate the air movement, large centrifugal fans with a displacement capacity of up to 400,000 cu. ft. of air per minute are installed, generally in drifts off the upcast shaft, or adit, and at the return end of the ventilating circuit. These fans are thus exhausting fans and by producing a region of low density bring the heavier air at the other extremity of the circuit into movement to correct the difference in density, so far as it is not prevented by the frictional resistance of the airways. A flow of air is thus established, and it is obvious that to enable this volume of air to be as great as possible, the frictional resistance of the mine airways should be maintained at the lowest practicable figure. To this end, main airways should be as large as possible, have sides as smooth as practicable, and be straight, any necessary bends being of large radius.REQUIREMENTS OF THE VENTILATION SYSTEMThe New South Wales Coal Mines Regulation Act contains stringent provisions on requirements of the ventilation system. The main points are expressed in the following extracts:&quot;In every mine which is in operation, unless a certificate of exemption from compliance with this rule has been granted by the Minister, whether any person employed therein shall be...

Jan 1, 1947

By H. W. Kropholler, L. A. Cramer, E. T. Woodburn, J. C. A. Greene

A generalized mathematical structure is proposed whereby internal species mass flows within a flotation network are defined uniquely by a matrix of enhancement factors. An element of the enhancement factor matrix is defined as the ratio of the mass flow of that species leaving a given cell in the concentrate to the species mass flow leaving the same cell in the tailings. To predict the enhancement factors, knowledge of flotation kinetics effects is required. Recently experimental data has become available relating to the performance of industrial flotation circuits which indicate that the discrete or discrete-distributed kinetic schemes are capable of reasonably effective simulations. These simulations show the importance of including froth effects. The prediction of performance of networks from small-scale batch tests on flotation streams shows that the model for the froth phase used in the simulations does not scale-up well and that aeration effects are also difficult to predict. The network analysis should be useful in differential flotation of complex ores and it is disappointing-in this context that little information on the kinetics of activation and depression is available.

Jan 1, 1976