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By John E. Riddell

This review is based on a questionnaire sent out to 24 Canadian exploration companies, known to be active in the mineral exploration field, concerning their practice in the use of applied geochemical techniques in Precambrian terrains. Of the companies questioned, 16 returned completed questionnaires and of these, ten companies stated that they had some experience in this type of work. Of the companies who did not answer or return the questionnaire in time I know that at least three have been quite heavily engaged in applied geochemical work in the glaciated Precambrian areas. I also know that these three companies have been reasonably successful in their ventures, so I feel the following figures and opinions are, if anything, on the pessimistic side. Before continuing with the paper I would like to express my personal thanks to the Chief Geologists, Geologists and Exploration Managers of the various companies who cooperated in making this review possible by answering the questionnaires and making available summaries of their work in the glaciated terrains. Of the companies who stated that they had no experience in geochemical prospecting in glaciated Precambrian areas it is interesting to note that only two have reported that they do not use applied geochemistry at all. Two companies have reported that they make use of applied geochemistry in New Brunswick in areas of-light glaciation. Their opinion is that it is a useful aid to other techniques in evaluating mineralized areas.

Jan 1, 1960

By T. Payne

Underground heat issues are mainly focused on the detrimental effects to a workers health. However, working in hot, humid conditions has other negative effects. Studies have shown that safety, productivity, workforce morale and operating cost are also worsened in these conditions. The human body has several mechanisms for rejecting heat and remaining cool. However, once the air temperature exceeds about 34°C, the only effective mechanism is by evaporation of sweat from the skin. This is assisted by acclimatisation which is the human body?s enhanced ability to combat extended exposure to heat. The body has to remain well hydrated when working in heat as even small degrees of dehydration cause significant decreases in the ability to work in heat. There are two ways in which heat load can be reduced: Through use of refrigeration/vent/cooling to reduce thermal stress on workers; Reduce the contribution that heat sources have to underground heat load (e.g. reduce idle time, fleet size, etc). Some of the sources of underground heat have the potential to be more manageable than others. Geothermal heat and heat from autocompression will be found in all mining situations in varying degrees depending on geothermal gradient and surface temperature, however, the use of equipment and blasting may be streamlined to reduce the underground heat load. It is through a combination of the available options that most mines will successfully control their heat related problems. Mt Isa, which has been a focus for heat related study in Australia, has successfully implemented protocols for working in heat. Through combining these with the installation of a surface bulk air cooling plant, Mt Isa has consistently reduced the incidence of heat illness. This is likely to be the most cost effective method of reducing heat load for deep mines in Australia. Shallower mines which may only occasionally encounter hot conditions should consider more portable cooling options. This study will review the heat issues in underground Australian metalliferous mines.

Jan 1, 2009

By Guy Reed, Russell Frith

In situ or pre-mining horizontal stresses are arguably the least well understood of the principal inputs into underground coal mining geotechnical engineering design, whether analytical, empirical, or numerical. This is a direct result of both the cost and difficulty of obtaining meaningful stress measurements, the various limitations of the measurement method in terms of sourcing strata types that approximate the assumed conditions of the post-measurement mathematics to convert measured strains into stresses, and a common practice by some geotechnical professionals to preferentially utilise generic values rather than interrogate the available measurement data for cause and effect relationships between horizontal stress magnitudes, directions and a range of associated controls. That numerical modelling simulations attempt to mimic reality but often rely on simplified generic horizontal stress input assumptions is a particular cause for further consideratio The paper attempts to further explore the nature of in situ horizontal stresses using a range of stress measurement results from the Australian coal sector supplemented by several international studies addressing the same basic issue, the result being a number of credible and highly relevant “cause and effect" inter-relationships between the three principal in situ stresses in addition to the influence of rock properties (e. Young's Modulus and Poisson's Ratio), cover depth and the larger-scale structural geological environment. In particular, the paper demonstrates that despite being commonly overlooked as a primary rock/coal material property, Poisson's Ratio and the associated K Effect are intrinsic to understanding 3D in situ stress measurement results and therefore, predicting in situ stress magni- tudes more generally for geotechnical analyses purposes. As a fundamental question, the paper addresses whether it is necessary and of engineering value to characterise in situ horizontal stresses: according to distinct "domains," in the same way that more easily identifiable geotechnical properties such as rock mass ratings, coal seam thickness, ply splits, and cover depth are often treated.

Jun 25, 2024

By C. G. Hunkin

In situ, or in-place leaching is concerned with the extraction of metals from natural mineral disseminations without removal from their geologic location which, in many cases, amounts to the reversal of the deposition process accompanied by a presumed increase in velocity of the processes, if the project is to be profitable. Solution mining processes involve removal of minerals such as sulfur, common salt, and potash, generally leaving cavernous voids, in contrast to in situ leaching which term is applied to the selective dissolution of a mineral from its gangue without sensible disturbance of the formation. Where such a process can be operated, the advantages are manifold and have been so recognized by miners from the earliest days of mining. Recent technological developments have encouraged a reassessment of the status of in situ leaching, and it now appears possible to extend the application of the method from a few isolated special situations to many uranium and copper deposits. Anaconda's interest in the techniques stems from long experience with vat and heap leaching, 'dump leaching, and natural leach activities associated with several established mines. Increasing activity through-out the industry has been noted, particularly in leaching low grade pillars and the peripheral zones of operating mines, often by the introduction of leach solutions via boreholes drilled from surface. Reactivation of dormant mines] using similar techniques has been successful. Over the long term, environmental improvement activity will lead to excess sulfuric acid production, even to a disposal problem. The cost of leach solutions and reagents must be reexamined in this light. The mineral industry now classifies as uneconomic deposits of readily soluole minerals whose potential value, on a per acre basis, may De several times that of many currently profitable oil field reser-

Jan 1, 1971

By J. Brune

The disaster at the Upper Big Branch (UBB) mine 2010 has demonstrated the destructive violence of a coal dust explosion by killing 29 miners in the worst mining accident the United States has experienced in almost 40 years. This explosion brought to light that the United States mining industry must strengthen explosion prevention and explosion hazard detection practices. Recent legislation such as the Mine Improvement and New Emergency Response Act of 2006 (MINER Act) pushed the strengthening of explosion and disaster response and miner protection in addition to stricter regulations on the sealing of abandoned areas and on conveyor belt flame resistance. The focus of this new act was on how to respond to a disaster or explosion, yet not much improvement was made with respect to prevention explosion disasters. Researchers at the Colorado School of Mines have recently concluded extensive research into methane and coal dust explosion prevention practices and regulations as it may be applicable to underground mines in the United States. This research aims to forward more studies into the use and adoption of standards and procedures that have been utilized in countries with strong explosion prevention histories.

Feb 23, 2014

By BARBOSA AMILTON, Denise C. R. Espinosa, David B. Dreisinger

Chelating resins can be used to recover important metals from different sources, and it is important to understand which resin is most suitable for each metal [1]. This review  benefits the mining industry because chelating resins can be used to recover metals from low-grade ores and mining tailings, increasing the industrial process efficiency [2–4]. Furthermore, the use of chelating resins in mining processes and mining tailings has the common problem of metals contamination, with iron being the main contaminant in low-grade ores and tailings. Understanding how contaminants decrease ion exchange efficiency is significant for industries [5

By Botelho Junior, Amilton Barbosa, Denise C. R. Espinosa, David B. Dreisinger

Copper and cobalt can be found on nickel laterite ores, and cobalt can be found also on copper ores, and many contaminants such as iron, aluminum, and magnesium are associated with these ores. In hydrometallurgical process, a purification step is necessary after leaching due to the presence of these impurities. Chelating resins are more selective for some metals than others, making them more efficient than cationic resins. This overview discusses chelating resin applications to recover copper, nickel, and cobalt from mining process and mining tailings and the effect of contaminants in leach solution. Chelating resins with iminodiacetate functional group can be used for selective copper recovery, and both iminodiacetate and bis-picolylamine resins are highly selective for nickel and cobalt. Chelating resins with the same functional group can have different performances on the kinetics of loading, because of variations of structure, the density of functional group, and degree of cross-linking. This article reviews commercial chelating resins that can be applied in leach solutions with different compositions, and also possible innovations for uses of chelating resins to recover metals from mining process and mining tailings.

By William H. Engelleitner

Agglomeration by balling in cylindrical or shallow pan devices dates back to the early part of this century. The first sintering tests conducted by Dwight-Lloyd on nonferrous ores included a mixing step for ore, flux and fuel carried out in a deep pan device similar to the balling pans, or discs, presently in use. Further work directed mainly toward sintering of ferrous and nonferrous ores always included a preparatory step, usually referred to as mixing, agglomerating or green-balling of the ingredients. In the late forties and early fifties two methods of particle preparation prior to firing were in general use. In Europe the balling pan was used predominantly, both as a mixer and as a pelletizer. In the United States many pilot plants and semi¬commercial plants used balling drums. When the first iron ore pelletizing plants were built in this country, the most frequently used device for green-balling was the cylindrical drum. At the same time, the pan device was used both in Europe and the United States for many other materials such as fertilizer, cement, flyash, alumina and copper concentrates, as well as to mix the feed for sinter machines. The difference between these two balling devices - -the drum and the disc - has been the subject of much discussion and is well covered by several papers included in the 1962 publication "Agglomeration' issued by AIMS, based on their 1961 International Symposium held in Philadelphia. (1)

Jan 1, 1965

By R. Woods, J. D. Wright

INTRODUCTION The Endako deposit was first explored in 1926, but development waited until the early nineteen sixties. It first came under the control of Placer Development in 1963, and early in 1964 a decision to bring it into production was reached. The deposit is located near the geographic center of British Columbia, and is served by an east-west communication system including a paved highway, mainline railway and good telephone, teletype, and computer facilities. The plant area is shown in Figure 1. The operation is known as the Endako Mines Division of Canex Placer Limited of Vancouver. First production was achieved in June, 1965, at a nominal rate of 10,000 tons per day, but it soon was closer to 15,000 tons per day. In 1967, two new grinding and flotation sections brought capacity to the present rate of approximately 27,000 tons per day. With mill heads of around 0.15 percent MoS2, production is about 14,000,000 pounds of molybdenum per year. A flowsheet of the operation is given in Figure 2. A legend for this flowsheet is given in Table 1. Published ore reserves are estimated at 214,500,000 tons at an average grade of 0.143 percent MoS2. PRIMARY CRUSHING The 85 or 100-ton haulage trucks dump over a grizzly into a 42 inch x 65 inch C.A.C. (Canadian Allis Chalmers) gyratory crusher.

Jan 1, 1976

By A. Filyk, R. Woods

The current plant practice at Molycorp, Inc., Questa Division, a molybdenum producer in northern New Mexico, is described. An outline of crushing, grinding, flotation, drying, and tailings disposal is included, with emphasis on metallurgy.

Jan 1, 1976

By S. A. Shuey, P. Taylor

The recycling of electronic waste (e-waste) tends to be a rather complex undertaking when considering the intimate bonding of materials in the average printed circuit board. The development of a recycling process is further complicated when considering the wide variety of products being generated under the heading of “electronics” as well as the constant change in materials of construction coupled with the speed at which electronics are changing. CSM researchers have undertaken a survey of the current state of pyrometallurgical processing of e-waste. This base-line will set the stage for the development of new recycling technology at CSM.

Jan 1, 2004

By Fahimeh Dehghani, Louis Ackah, Tathagata Ghosh, Justin Godbold, Jia Liu, Meisam Peiravi, Manoj Mohanty, Azam Baharlouei

Primary economical deposits of rare-earth elements (REEs) are exhausting all over the world, and it has become necessary to find new sources and methods for their extraction. In addition, increasing the application of REEs in modern technological society has increased its demand globally. One of the important movements to compensate for the future shortages of critical metals is the recovery of REEs from recyclable materials. This paper presents a review of the classification and extraction methods, as well as general applications of REEs with emphasis on secondary sources such as coal and coal byproducts, iron ore tailings, apatite, and phosphate byproducts. An overview of the current state of knowledge on the various methods of REE beneficiation and extraction is covered. These methods include physical separation, as well as hydrometallurgical and bio-hydrometallurgical techniques. The application of these REE extraction techniques for enhanced recovery has been driven primarily by the unique industrial application of these important elements. This paper further explores the existing and potential environmental challenges associated with REE extraction. The authors have presented a wide array of literature, in-depth discussion of the subject, and a succinct summary of processes and relevant case studies.

Sep 23, 2020

By Weiguo Xie, MARK LAPUTKA

The pyrometallurgical industry plays a vital role in producing metals for our modern life. With growing demand of metals and declining grade of mineable ore, innovations become critical for many mining companies. It is necessary to conduct a review of recent improvements to the pyrometallurgical industry on analytical measurement techniques, process and equipment improvements, and computer-based modeling/simulations. Many of those innovations tend to be applied to wider metals, and not be restricted by a specific metal. Therefore, we tried to cover the wide applications of many improvements to wider range of metals to reflect this trend. The challenge of a lack of robust measurement techniques under high-temperature conditions within a furnace hinders optimization of a pyrometallurgical process. Some future opportunities in the pyrometallurgical industry on analytical measurement techniques, computer modeling, and processes and equipment have also been outlined and discussed.

Jan 26, 2021

By Weiguo Xie, MARK LAPUTKA

The pyrometallurgical industry plays a vital role in producing metals for our modern life. With growing demand for metals and declining grade of mineable ore, innovations become critical for many mining companies. This has given rise to the need for a review of recent improvements to the pyrometallurgical industry in terms of analytical measurement techniques, process and equipment improvements, and computer-based modeling/simulations. Because many of these innovations tend to be applied to a wider scope of metals, not restricted to a specific metal, we studied the broad applications of many improvements to a wide range of metals. We found that the challenge of a lack of robust measurement techniques under high-temperature conditions within a furnace hinders optimization of a pyrometallurgical process. Some future opportunities in the pyrometallurgical industry on analytical measurement techniques, computer modeling, and processes and equipment were also outlined and discussed.

During the past year a number of significant advances in geostatistics have been published. These were presented at the 13th APCOM Symposium in Clausthal, Germany and at a NATO Advanced Study Institute on Geostatistics in Rome, Italy. Of greatest importance is the work that has been done in establishing methods which correctly predict the cutoff grade-tonnage curves, and the average grade of ore-tonnage curves for deposits in which ore and waste are intermingled. Grade-tonnage curves based on estimates made from widely spaced exploration data have been found to underestimate the grade of ore and overestimate the tonnage present. This problem has been remedied by the calculation of conditional probability distributions for the unknown grade of a block. Another advance has been made in the field of geostatistical estimation for deposits in which a trend is present. Previously a technique known as universal kriging has been used, which involves much subjective judgement as to the trend fitted. A new technique, generalized increments, allows computer estimation of such deposits with much less subjective judgement. Computational efficiency of geostatistical methods has continued to improve to a point where a geostatistical estimate can be obtained for little more than the cost of any other computerized method.

Jan 1, 1976

By D. Royston

The use of large face angle shell lifter-liners in combination with wider lifter spacing has grown in recent years, especially in large SAG mills. The claimed benefits are reduced ball on liner impact, leading to increased liner lives and less ball breakage, and both reduced packing and improved ball-on-charge impact, leading to improved mill performance. This review covers available published data on several mill sites and aims to quantify the observed benefits.

Jan 1, 2003

By John N. Murphy

The past five years have seen communications techniques and hardware developed by the Bureau of Mines and its contractors increasingly brought into use in U.S. mines. The Bureau of Mines philosophy has been to help develop and introduce new hardware that goes as far as possible toward meeting the mining industry's needs. The Bureau of Nines programs are also designed to provide continuous fallout of new communications capabilities which are introduced to the mine operators as they occur. As more progress is made in meeting mine comnications needs, it is hoped that the mining industry will readily adopt the equipment and techniques that it finds most useful in meeting its individual needs. This paper reports on recent advances achieved in the development of improved nine communications systems.

Jan 1, 1976

By James H. Allen

The air lift method of pumping water is discussed. A review of several large diameter hole drilling projects that used reverse circulation air lift techniques is presented. Proposals are made for reverse circulation flow rates for slow rates of bit penetration (5 fph) as well as reverse circulation flow rates for faster rates of bit penetration (10 fph). The Ingersoll- Rand air lift equations are modified for rotary drilling operations. By establishing minimum reverse circulation flow rates and utilizing the modified air lift equations, the establishment of minimum circulation equipment sizes and a more definitive requirement for improved bit body design should result.

Jan 1, 1976

The support of the roof in coal mines remains a critical safety issue with 3 fatalities from roof falls in 2007 and 430 injuries from roof falls in 2006. A snapshot survey by the authors of room design and support details as well as unplanned falls of ground in the industry revealed some useful data concerning support use, seam details, fall dimensions, bolt lengths and spacing and the stand-up time.

Jan 1, 2009

By G. J. C. Young

In 1986 the city of Johannesburg celebrates its first century of existence. The fact that the city was founded to exploit the gold deposits which underlaid it, prompts this review of the gold process development in the mining industry of South Africa. Clearly a complete history of, the gold recovery process to date is not called for and it is proposed therefore to outline the most significant developments which have taken place since the middle 1930's, that is to say the last 50 years or so. Prior to this period the industry had seen the development of comminution processes employing cone crushing in closed circuit with vibrating screens followed by grinding in rotating mills and the gradual disappearance of stamp mills. The all sliming process was well established as a viable route and continuous dewatering in thickeners, continuous leaching and filtration were serious rivals for the earlier batch processes. Continuous processes for gravity concentration had also been developed and the recovery of gold from pregnant solutions employed cementation on zinc dust as opposed to shavings. Thus at the beginning of the half century under review the industry had adopted, or started to adopt, many of the processes still accepted as modern practice. However in some areas little change was evident this was especially so in the smelthouse where some thirty more years were to elapse before the hand stoked coal fired calcine and reverbatory furnaces were replaced by more environmentally acceptable electric furnaces. The most significant feature in recent history has been the mining of progressively lower grades of ore and the retreatment of tailings from earlier operations, much of the latter comprising tailings only a decade or even less in age. Notable among these operations are those on the East Rand near Springs in the Transvaal, in the Orange Free State at Welkom and more recently, massive reclamation of tailings close to the city centre itself. The carbon in pulp (CIP) process has been much publicised in recent years and all new plants erected during the 1980's have adopted this route for gold recovery. However the major proportion of tonnage milled in the industry is still subjected to the more traditional process of liquid solids separation by vacuum filtration. The discussion that follows will centre largely on the developments in the traditional process route, which for the sake of completeness is listed below: Comminution Dewatering Leaching Liquid solids separation Gold recovery Smelting

Jan 1, 1985