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By John E. Riddell

This review is based on a questionnaire sent out in 1959 to 24 Canadian exploration companies, known to be active in the mineral exploration field, concerning their practice in the use of applied geo-chemical techniques in Precambrian terrains. Of the companies questioned, 21 returned completed questionnaires and of these, 15 companies stated that they had some experience in this type of work. Of the companies who stated that they had no experience in geochemical prospecting in glaciated Precambrian areas it is interesting to note that only three have reported that they do not use applied geochemistry at all. The others have reported that they make use of applied geochemistry in New Brunswick and in the Cordillera in areas of light glaciation. Their opinion is that it is a useful aid when accompanied by other techniques in evaluating mineralized areas. GEOCHEMICAL SURVEYS Table I reviews the type of geochemical surveys used by these companies, and the following points of interest should be noted.

Jan 11, 1960

By J. W. Stevenson

The need for a separate ventilation department within the management team was recognized by the management of U. S. Pipe and Foundry before the company was purchased by Jim Walter Corporation in January, 1970. Because the coal beds of the deep underground coal properties owned by Jim Walter Resources lay 1300 to 2200 feet below the surface, efficient mine ventilation practices are essential through shaft openings varying from 16 to 22 feet in diameter. The extremely high methane gas quantity indicated to be in the coal bed because of the depth of cover and documented by various U. S. Bureau of Mines tests and demonstrated by early mining proved the need to implement this early management decision. At U. S. Pipe and Foundry mine ventilation was a function of the Mining Engineering Department with ventilation personnel assigned to the mine receiving their day to day work assignments from the mine manager or mine foreman. At Jim Walter Resources, the General Manager - Ventilation reports to the Senior Vice President, Mining Engineering, who reports directly to the President, Mining Division, Figure 1 (Company Organization Chart). Position descriptions are static; however positions are dynamic and consequently the degree of emphasis of specific duties and responsibilities change depending not only upon the aptitude of the individual performing the job but also upon his ability to meet the needs of his supervisors; and ultimately upon his ability to react to the economic forces directing our society. The following describes the duties and responsibilities of the General Manager - Ventilation, Figure 2.

Jan 1, 1980

By Christian Maguire

Tunnel contracts in New York have in recent years had few bidders with the bids received being much higher than anticipated. Since 9/11, security has become a key issue in planning key infrastructure projects in New York. This is especially true in the case of large water supply tunnels. Striking the right balance between cost and security was the major factor in determining the best configurationfor the Kensico-City Tunnel. This paper outlines the efforts made to determine realistic probable bid costs for the tunnel contracts, and the innovative approaches taken to deal with security issues.

By M. Dobbins

The advent of the more efficient and effective rare-earth roll (RER) separator in the early 1980s began a new era of dry magnetic separation. The RER units quickly became the separator of choice within the materials processing industry. Though RER separators are now commonplace throughout the world, only modest advancements have been made to the original design. This paper details recent, more significant, rare-earth magnetic separation developments. These developments maintain the best features of existing technology while minimizing shortcomings. The discussion includes discerning features that aid in better metallurgical performance. Also discussed are improved mechanical aspects that allow for both easier operation and maintenance. Performance details from various test programs are included.

Jan 1, 2010

By A. T. Yu

As the first loads of Noamundi iron ore rumbled into the new 54-in. Gyratory Crusher on March 30, 1968, one of India's largest and most modern iron ore processing complexes began operations. The completion of the $13 million mining and processing complex brought to a successful conclusion the second chapter of a phased expansion program initiated in 1958 by India's gigantic Tata Iron and Steel Co. The completed complex will yield annually 2.5 million tons of washed, sized ore and sinter fines destined for Tata's furnaces at Jamshedpur. Hewitt-Robins Div. of Litton Industries was awarded the turnkey project on the basis of world- wide competitive bids. Eighty miles southwest of the city of Jamshedpur, Noamundi lies on an approximate geographic grid of 22º-5' latitude north and 85º-30' longitude east. The mine is approximately 600 ft above sea level.

Jan 11, 1968

By Pengfei Pan, Lianjun Guo, Houguang Sun, Donglin Xu, Chi Yang, Lihua Luan, Daning Zhang

"Based on the introduction of production technology of Anqian mining company, the stope ore mass distribution was analyzed in detail. The processability indexes of different grade ores were obtained with magnetic tube whereas the grinding time, concentrate grade and concentrate yield were measured. On the basis of digital ore deposit model which integrates ore natural attributes and processing attributes, two stages of ore blending optimization models were established. The first stage model sought the minimum of stope ore transportation cost under the restraints of output ore grade and stope production. The second stage was a system optional model that aimed at the furthest use of resources meeting not only the production constraints of mining field and process field but also ore beneficiability and the system output requirements of the concentrate grade. Lastly, the solving method of big M simplex algorithm was discussed and used in production. 1. Foreword China is the biggest iron ore consumption market. But most of iron ore deposits in china possess such features as low grade, complex compositions, weak magneticity and refractoriness. Under the current economic and technical conditions, rational utilization of low-grade and refractory iron ore is strongly needed to improve the utilization ratio of mineral resources and keep mine development sustainable (Lei 2011). In recent years, the domestic research institutions and mines made a lot of achievements of rational development and utilization of low grade iron ore resources in the beneficiation technology and equipment, high and low grade balance, cost and tax analysis (Wang and Zhao 2013, Zhang 2014, Zhu and Li 2014), laying the foundation for reasonable utilization of low grade iron ore. In this paper, Anqian mining company is taken as an example in which the production conditions, raw ore quality control, different grade of ore processability, and ore blending optimization mode in mining pit and processing plant were discussed to achieve the maximum utilization of low-grade refractory ores under the economical and reasonable conditions. This will ensure the stable operation of mining joint ventures and maximize the enterprise's production life and therefore, maximize the economic and social benefits in the enterprise life cycle."

Jan 1, 2017

By M A. Lund, C D. McCullough

In Australia and worldwide, open cut mining has become increasingly common over the last few decades through changes in excavation technology and ore economics. However, such operations frequently leave a legacy of open mine pits once mining ceases. Pit lakes will then form in mine pits that extend below the water table when dewatering operations cease. Pit lake waters are typically contaminated with metals, metalloids, saline or acidic/alkaline and rarely approach natural water body chemistry. Physically, pit lakes have unique bathymetries, are often strongly wind sheltered and have very small catchments. Nevertheless, pit lake waters often constitute a vast resource but of limited beneficial use (due to water quality issues); with a potential to contaminate regional surface and ground water resources. Water in pit lakes has the potential to be useful for a range of purposes in the Australian context of characteristic hot, dry climate and relatively few natural water bodies. Consequently, pit lakes can be seen to represent either a significant liability or a water resource to mining companies and regional communities. However, the lack of knowledge on pit lakes continues to hinder their proper management. This paper summarises the limited information currently available on water quality associated with Australian pit lakes. Information on pit lake occurrence, distribution and water quantity and quality is not nationally collated and requires immediate and ongoing attention from both mining companies and regulating authorities. Lack of a readily available database for pit lake occurrence, distribution and water quality fails to realise the potential for these water resources by both mining companies and Australian communities. Lack of access to pit lake quantity and water quality data may also lead to failure to manage this significant source of mining environmental risk.

Jan 1, 2009

By A. J. Dudzik

In 2006 Arch Materials initiated the development of an underground limestone mining complex. The decision to proceed with the project was the end result of several years of market research and geological reconnaissance. The scope of the project included the construction of two declines to the mining horizons located approximately 900 feet below the surface, the means and methods of this phase will be the primary focus of this discussion. The design, fabrication and erection of a state of the art crushing and screening processing plant which when completed will have the primary crushing located on the mine level allowing uniformly sized material to be brought to the surface by means of a highly efficient conveyor system and a surface portion of the plant where material would be additionally processed, screened and stockpiled into specific product types. Also included in the scope of the project is the construction of offices, warehouse and shop facilities necessary to support the operations, commercial sales and distribution of the finished products.

Jan 1, 2010

By T Gill, A Faragher, B Scott, V Kakebeeke

In 2000, after six year intensive exploration for high-grade haematite deposits, Rio Tinto included the channel iron deposits (CID) as a specific iron ore target in the Hamersley Province iron ore exploration program. The exploration model was simple and based on the then current understanding of CID genesis. Fundamental to the model was an interpretation that CID deposits after their final accumulation stage could be entirely concealed in their channels. Inversion to mesas and therefore exposure of the CID profile would only occur in areas where the modern drainages follow the ancient and have significantly incised their current bedrock. The model took encouragement from observations at Bungaroo Creek, where large CID accumulations occur in a deep valley incised in the Wittenoom Formation concealed below recent valley fills derived from the surrounding BIFs. Also, in the headwaters of the Yandicoogina system CID occurs below a more recent cover of calcrete and clay. After a number of failed or partially successful attempts, exploratory drilling in 2002 in the Caliwingina valley in the northern Hamersley Range identified significant CID mineralisation. Subsequent drilling programs from 2003 onwards revealed the presence of a large CID system, which stretches from the middle reaches of the Caliwingina Creek to deep under the sediments of the Fortescue Valley, a channel length of more than 30 km. Although the drilling is still somewhat sparse, the geological resource estimation suggests that Caliwingina is presently the third biggest CID system of the Pilbara (after Yandicoogina and Bungaroo Creek) and is of comparable size to the premining Robe River system (1.6 Bt), with comparable Fe-grades to the Yandicoogina global resource grade (57.7 per cent Fe). Large detrital and canga deposits overlie the Caliwingina CID, or interfinger with it, and although the economics of these are presently unfavorable, could ultimately present a low-grade iron resource of slightly smaller size to the CID mineralisation at Caliwingina Creek. Together with the recently discovered Serenity and Solomon deposits, as well as Cabbage Gum Bore and other smaller occurrences, the Caliwingina Creek deposit is part of a major new CID district in the central Hamersley Ranges, approximately halfway between Yandicoogina and Robe River. Although exploration in this new district is still underway, the preliminary indications are that this area will provide a total CID resource well over 3 Bt, and is on a par with the major known CID systems in the Hamersley Province.

Jan 1, 2009

By David S. Brown

What troubles me so often about debates over the environment, which I have heard since I entered government in the late 1960's, is that the issues are so often presented as a false dilemma--the either-or fallacy in logic. The either-or fallacy allows only two possible choices: Either protect the environment or exploit it. In reality, however, there may be a few more options. The diverse, often competing, values that the Earth offers require us to weigh and balance those options through a range of policy options. A quality environment and economic growth and opportunity are not mutually exclusive. First, let me acknowledge that I support a set of resource values recognized in U.S. laws and deemed important down through history for the success of free, progressive, and secure societies: the importance of access to raw materials. Increasingly, however, mineral raw materials have been viewed at best as not particularly relevant to a sophisticated, technologic society, and at worst monstrously destructive of our natural environment. Both perceptions, in my judgment, are wrong.

Jan 1, 1989

By F. Czerwinski

Mechanically fragmented chips of an AZ91D magnesium alloy were transformed into a semisolid slurry within the Thixomolding® system. Microstructural analysis of a material at various processing stages revealed that the cold deformation of the alloy, experienced during chipping, led to the recrystallization and growth of equiaxed grains which were subsequently converted to the globular structures by melting the grain-boundary network.

Jan 1, 2004

Mine drainage and mine reclamation are topics of major interest to the mining industry, federal and local governments, and the general public. This publication and its companion three volumes are the proceedings of a conference held in Pittsburgh, Pennsylvania, April 24-29, 1994. There were twelve sessions (69 papers) that dealt with mine drainage, including modeling, geochemistry, prediction, treatment, control strategies, characterization, hydrology, and case studies. These sessions comprise volumes 1 and 2. The six sessions (34 papers) that dealt with reclamation and revegetation of disturbed lands are included in volume 3. Volume 4 includes the six sessions (34 papers) that dealt with such topical issues as fires at abandoned mine sites, subsidence, hydrology, mine wastes, and policy. Poster session presentations are represented by 49 papers and 92 abstracts that have been placed in the back of volumes 2, 3, and 4, consistent with the subject of that volume.

Jan 1, 1994

By T. Hollingsworth

The Boddington Gold Mine, located near Perth in Western Australia, has recently completed the construction of a new process plant. An overland conveyor system was installed to convey the ore from the primary crusher to the process plant. This paper will discuss the overland conveyor?s mechanical design including dynamic analysis and the selection of primary mechanical and electrical components.

Jan 1, 2010

By T. Banerjee, D. Felsher, G. Leavoy

"Lake Shore Gold is engaged in commercial gold production at both the Timmins West and Bell Creek mines, located in Timmins, Ontario. Run of mine ore is processed at the Bell Creek mill which consists of a conventional gold mill flow sheet involving crushing, grinding, gravity concentration and carbon-in-leach (CIL) for gold recovery. Since 2009, the operating capacity of the mill has been upgraded from 2000 tpd tonnes per day (tpd) to over 3,000 tpd. The most recent expansion involved the installation of a low aspect ratio SAG mill to replace the secondary crusher. Without operational data on the low aspect mill, combined with a site team that was new to SAG milling, there were many challenges in achieving the target throughput from the circuit. Through the implementation of AwaRE advanced controllers, running in closed loop with PRC fragmentation cameras as well as embedded PARC modules within the Allen Bradley PLC, the site was able to rapidly develop a best operating practise and has been successful in creating a stable and consistent operational environment. The process, lessons learned and eventual solution will be reviewed in this paper.INTRODUCTIONLake Shore Gold is engaged in commercial gold production at both the Timmins West and Bell Creek mines, located in Timmins, Ontario. Run of mine ore is processed at the Bell Creek mill which consists of a conventional gold mill flow sheet involving crushing, grinding, gravity concentration and carbon-in-leach (CIL) for gold recovery. Since 2009, the operating capacity of the mill has been upgraded from 2,000 tpd tonnes per day (tpd) to 3,150 tpd. The most recent expansion involved the installation of a low aspect ratio SAG mill to replace the secondary crusher. This endeavor was split into two phases: the expansion of the back-end (Phase 1) and the front-end (Phase 2) of the mill. Phase 1 of the expansion was completed at the end of 2012 and involved enhancements and capacity addition to the leaching and adsorption circuits, which increased the mill’s capacity to 2,500 tpd. Phase 2 of the expansion commenced at the end of July 2013 and involved the expansion of the crushing and grinding circuits. The expanded front-end of the mill now has a capacity of 5,500 tpd, and processes ore from both Bell Creek and Timmins West mines. The updated flow-sheet, as shown in Figure 1, illustrates the replacement of the two-stage crushing and ball milling circuit with a single stage crusher and a low aspect ratio SAG mill."

Jan 1, 2015

By Anthony D. Szpak

The purpose of this program was to demonstrate the feasibility of Illuminating various types of underground coal mining machinery as required by the Federal Coal Mine Illumination Standards Part 75.1719 to 75.1719-4 Code of Federal Regulations Title 30. Nine various machines were illuminated and the illumination systems were evaluated for a 3 month period of operation. Factors evaluated were ease of implementation, reliability, ease of maintenance, acceptance by mine workers and operators, Illumination degradation and durability.

Jan 1, 1981

By Oswald J. Heinrich

This question having been repeatedly raised, and particularly revived in a discussion at the last meeting of the Institute, I beg to submit the following remarks, based partly upon personal experience, partly upon the results of large works in Europe, establishing, years ago, the practicability of certain methods, which may therefore be considered to have passed the stage of mere experiment. Before entering upon the merits of one system or the other, it is indispensable to lay down some recognized principles, which ought to serve as guides, in arriving at fair judgments in questions of this character. In a profession like that of mining, locally so much influenced by combinations of circumstances too various to mention, it is difficult to do more than lay down the main features of a system based upon general laws and recognized facts, leaving the details to the sound judgment and experience of the engineer, who, by virtue of his education, ought to be able to make such choice and such modifications in the plans of a mine as the particular case demands. Mineral resources, in some countries the sole property of the owner of the soil, in others controlled by the strong hand of a government, are nevertheless a gift of nature, in which, indirectly, the whole of the human race has as real an interest as the immediate owner himself. This interest requires, at least, that no unnecessary waste of

By Jr. Gabler

Because of concern over the availability and reliability of an uninterrupted supply of manganese and other materials, the U.S. Congress requested that the U.S. Bureau of Mines (USBM) study the /low of strategic and critical materials in the economy to delineate and quantify the production areas where metal values are lost. As a result, the USBM developed a generic computerized commodity flow model that is readily amenable to updating. The original model developed for cobalt, with slight modifications, was used to track the flow of manganese. This report follows the flow of manganese through its metallurgical and chemical applications and highlights areas where significant losses occur owing to downgrading, export, or disposal. The study indicates that materials containing 695,000 short tons (st) of manganese were consumed domestically in 1990. Scrap recovery specifically for manganese recycling was insignificant. However, considerable manganese was recycled through processing operations as a minor component of ferrous and nonferrous scrap and steel slag. The major loss category is manganese lost in steel processing, 323,156 st or 46 pet of the 1990 apparent consumption. Most of this loss reports to steelmaking slags. Recovery from slags is technically feasible, but is not economically feasible.

Jan 1, 1995

By Walter Voglauer, Elisabeth Zechmeister

Description of Project: The four photos show a chimney blasting operation in Vienna’s district of Floridsdorf on May 4 2011. The blasting was done with two types of charges. An internal charge provided a force of blast which resulted in 135 single electrical blasting caps initiated detonations on the basic ensured the straight collapse of the chimney. The preparation work was done by reserve force military engineers. The series of photos were shot by Elisabeth Zechmeister. She works in the Austrian DOD but not as a professional photographer; much more she did all activities in her spare time.

Jan 1, 2013

By S. K. Kawatra, T. C. Eisele

"Coal-fired electrical power generation plants produce 56% of all the electricity in the U.S., burning approximately 860 million tons of coal annually. This results in the production of 58 million tons of fly-ash; 19 million tons of bottom ash and boiler slag, and 23 million tons of desulfurization sludge.s annually. These are a considerable disposal problem, and it would therefore be very valuable to be able to sell these residues and by-products as useful materials, rather than paying to dispose of them in landfills. However, utilization rates are currently very low, below 32% even for the most thoroughly commercialized combustion byproduct (fly-ash). This poor utilization rate is a result of the high impurity content of combustion byproducts, which makes them unsuitable for existing markets.Mineral processing techniques are useful for upgrading and utilizing combustion by-products. Fly-ash can be processed to remove unburned carbon, or utilized as a binder component in ore pelletization and agglomeration processes; bottom ash can be processed to produce certain aggregate grades; CO2 emissions can be sequestered using modified leaching techniques; and many scrubber sludge’s require processing before they can be used for producing gypsum products.The experiments described in this paper were carried out to study the application of mineral processing techniques to upgrading combustion by-products, particularly flue-gas scrubber sludge. A process was developed for upgrading unoxidized Flue-Gas Desulfurization (FGD) sludge’s by removing the primary impurity (unreacted limestone). A combination of hydrocycloning followed by froth flotation reduced the limestone concentration to as little as 1.7%, while recovering 66% of the sludge weight as a clean product. The recovered limestone was sufficiently concentrated that it could be recycled to the scrubber for more complete utilization."

Jan 1, 2003

By Willard C. Lacy

A mining operation begins with prospecting and exploration-stages with long periods of investment and high risk of failure. However, success in exploration ultimately determines survival of the mining industry. Prospecting and exploration may discover evidence of a mineral occurrence and outline its size and character, but ore deposits that support mining are "made" through the collective efforts of project geologists, geophysicists, geochemists, metallurgists, engineers, chemists, lawyers, and even politicians (Joralemon, 1975). Some deposits may go through multiple cycles of rejection and recommendation, discovery and development, decline and abandonment, rediscovery and development, etc., as economic, technological, or political conditions change or geologic understanding is improved. Peters (1987, p. 233) graphically illustrates the normal life cycle of a mine and the position of exploration in the cycle (Fig. 4.0.1). During the past fifty years, mineral exploration has evolved from comparing evidence of mineralization of prospects with that of known deposits to a more quantitative science employing many facets of geochemistry, geophysics, multispectral sensing from space, computer data storage, analysis, modeling, and most importantly, a better understanding of ore genesis. This modem approach to exploration began in the late 1940s and continues to develop. Exploration efforts peaked in the 1960s with emphasis upon the search for porphyry copper deposits, Mississippi Valley lead-zinc deposits, and volcanogenic massive sulfide copper-lead-zinc deposits. It peaked again in the middle and late 1980s with emphasis upon micron-size disseminated gold and epithermal and stratiform precious metal deposits.

Jan 1, 2008