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By D Kepert

It is the role of the exploration geologist to create wealth through the discovery, delineation and characterisation of economic mineralisation. This requires a critical depth of geological understanding.Unfortunately, the resource industry is well known for its cyclic nature. Many of the current generation of workers have only ever experienced the boom of the ‘super-cycle’ and are only just discovering the negative side to the business. For the case of the geologist and especially the exploration geologist, the magnitude of peaks and troughs are usually amplified and may become destructive to all parties. During the uptime a healthy stream of exploration good news becomes the staple diet of company releases, in particular those of junior companies attempting to bolster the share price. The geological knowledge and experience gained thus forms a significant and integral part of the value and therefore, future of a company. On the downturn it is often viewed that geologists are a luxury, an optional extra and a burden on the bottom line with companies entering a period of memory loss and myopia.Retention of geological knowledge however remains critical as projects, companies and cycles mature. Beyond exploration per se, this knowledge becomes both fundamental in de-risking and commercialising an asset (through development or divestment) and in positioning the company for cyclic or counter-cyclic opportunities.The growth and retention of this knowledge base is difficult to quantify in terms of direct value but becomes one of a successful resource companies greatest assets. At worst, its loss can lead to millions of investors’ funds wasted on missed opportunities, drilling, or poorly designed plant and mine.But the rocks are around for the longer haul and pay little notice to the vagaries of the scurrying of Man.This paper reflects on some of the authors own observations through 25 years of iron ore exploration, in why it is critical to always rigorously question the prevailing geological (mis)understanding and the technical and commercial benefits which that may bring, and looks forward to the future.CITATION:Kepert, D, 2015. Geology – the affirmative case, in Proceedings Iron Ore 2015, pp 285–298 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By T. Joseph, E. Zheng, M. Curley

"Hydraulic transportation efficiency and production optimization are considerations in the surface extraction of Athabasca oil sand deposits. To reduce the dependence on haul trucks, it is possible to extend the hydraulic transport system to production faces using a mobile at-face slurry system (AFSS). The flexible arrangement of connected pipelines transports slurried minerals from the mining face to the processing plant. An experimentally verified mathematical model indicates the friction loss of oil sand slurry associated with the AFSS. Laboratory-scale testing enables extended analyses for examining pipeline slurry transport in an oil sands environment.RÉSUMÉ L’optimisation de l’efficacité du transport hydraulique et de la production sont des considérations importantes dans le domaine de l’exploitation à ciel ouvert des gisements de sables bitumineux de l’Athabasca. Afin de réduire la dépendance envers les camions de transport, on envisage d’étendre le système de transport hydraulique aux fronts de taille à l’aide d’un système mobile de transport des matériaux sous forme de boue à partir du front de taille (AFSS, de l’anglais at-face slurry system). L’organisation flexible des conduites reliées permet le transport de minéraux à l’état de boue du front d’exploitation jusqu’à l’usine de traitement. Un modèle mathématique vérifié de manière expérimentale indique la perte de charge par frottement des schlamms provenant du traitement des sables bitumineux associée à l’utilisation de l’AFSS. Des essais en laboratoire permettent de mener des analyses approfondies portant sur le transport de boues dans des conduites dans un environnement de sables bitumineux. INTRODUCTIONObjectives and scope of studyThe at-face slurry system (AFSS) concept has become a competitive means for materials handling to optimize haulage system efficiency and cost. The mobile and flexible arrangement of the AFSS introduces a unique set of hydraulic transport problems. This paper will focus on developing the mathematical models governing the friction and head losses within the AFSS concept.Background of the problemLarge-capacity shovels and dump trucks are increasingly used for excavation, loading, and hauling in the operation of surface mining. Production cost and efficiency optimization are demanded during the Athabasca oil sands (Alberta, Canada) mining process to secure North America’s energy supply. Increasing haulage distances, rugged terrain, and a constrained mine environment are conditions that will reduce the effectiveness of the shovel-truck haulage system (Frimpong, Szymanski, & Changirwa, 2003). In such conditions, the tire heat index and weight, distance, and time limits for truck haulage can be exceeded, simultaneously creating extreme tire wear and high maintenance costs. In addition to low production cost and equipment effectiveness, a mining environment also requires efficient waste-material recycling and distribution. Waste materials need to be recycled from the processing plant to a new destination such as a tailings dam, or replaced in mined-out areas such as backfill. The Athabasca oil sands configuration and location characteristics result in a mining environment that would benefit from flexible pipelines for constant production and an efficient waste-material recycling process."

Jan 1, 2017

By A Yáñez, P Vallejos, R Grau, J Yianatos

In flotation cells, especially in large flotation units, froth management is a crucial variable that should be considered during the design phase or optimised to improve the performance of existing flotation circuits. This paper presents a simulation evaluation of the effect of launder design on the metallurgical performance of an industrial flotation circuit consisting of five TankCell® e630 (630 m3 ) cells in a Cu rougher duty. This analysis was carried out using a new industrial simulator, which was built on a wide database collected from many industrial concentrators. This tool is currently incorporated into HSC Chemistry® software and allows evaluation of the effect of launder design on mineral froth recovery, water recovery, entrainment, and other variables to be quantified. The industrial flotation circuit was evaluated under different launder design scenarios, considering an actual flotation circuit that includes TankCell® e630 cells for calibration and as a reference (baseline). Firstly, two different designs were evaluated in the full circuit: a standard launder design and a new launder technology. It was found that the new launder technology enabled improvement of the mineral recovery along the circuit, mainly for coarse particles, due to the improvement in froth mineral recovery. Next, the partial upgrade of the launder design along the circuit was analysed. Thus, the new launder technology was evaluated in the first and the last two cells of the bank. The results showed that upgrading the launders in different cells along the circuit delivered an increase in the final recovery with respect to the baseline, with a partial impact on the concentrate grade. However, these changes are less than those when evaluating the full upgrade scenario. A partial launder upgrade either in the first or last two cells of the bank showed similar final recoveries, but the latter enabled a slightly higher concentrate grade (about 1 per cent higher) to be achieved. Finally, the evaluation of launder design using the industrial simulator made it possible to estimate its effect on variables that are not commonly obtained from plant surveys, including froth recovery per particle size, collection recovery per particle size and liberation, gangue entrainment and bubble loading grade.

Aug 24, 2022

By Richard A. Allwes

This Bureau of Mines report presents a procedure for the design of an arch canopy for use in rehabilitating a high-roof-fall area. Only dy-namic line loading of an unbackfilled arch canopy at its crown is considered, and the procedure does not account for an asymmetrical loading condition. The evaluation of whether an arch canopy is suitable for a particular installation depends on many variables, including in-mine conditions and the engineering properties of the structure. However, a general evaluation can be based on a comparison of the arch's maximum crown deflection and a prescribed allowable crown deflection. The design procedure is based on the concept that when an arch canopy is sub-jected to impact loading at its crown and deflects from its unloaded state to maximum crown deflection, the structure absorbs strain energy, both elastic and plastic. As a result, this strain energy can be calculated from a static load-displacement diagram for the structure. The significance of this design procedure is that it gives mine personnel an analytical tool to select an arch canopy to meet the dimensional and functional requirements of a mine entry and a prescribed allowable crown deflection.

Jan 1, 1987

The Environmental Session will consist of five papers dealing with various aspects of trace elements associated with coal. Analytical procedures to determine the amounts of trace elements will be discussed. Other papers will deal with trace elements in streams downstream from coal mines, potential pollution from wastes from coal preparation plants, potential recovery of trace elements, and potential pollution from trace elements as a result of the combustion of coal.

Jan 1, 1979

By Dave Rose, David G. Meadows, Mike Westendorf

"Copper Mountain’s concentrator was commissioned in May 2011. The circuit consists of a 34’ x 20’ EGL SAG mill, a Raptor 900 pebble crusher and two 24’ x 39’6” ball mills. Each mill is equipped with a 2 x 8500 HP dual pinion drive system. The plant was designed to process 1585 mtph of SAG feed. From startup, the mill struggled to meet the required production rates. Over time, a major initiative that involved blasting and fragmentation, optimization of the SAG mill in terms of discharge grates, ball size and slurry density, and operation of up to three mobile pre-crushing plants resulted in significant increases in throughput. In parallel, a number of modeling tools, including JK SimMet, were run based on plant benchmarking exercises. Samples collected at the mine site during ramp up confirmed the very competent nature of the ore with drop weight - A*b values of less than 24 being recorded on a variety of plant feeds and lithologies. After due consideration including demonstration of proof of concept, a new pre-crushing circuit incorporating an XL2000 cone crusher and associated screening equipment was designed, constructed and commissioned at the site in August 2014. This paper reviews the history of the original circuit design, the various optimization steps taken and impacts, together with the final pre-crushing circuit and net results.IntroductionThe Copper Mountain Mine is located approximately 20 km south of Princeton, British Columbia, Canada (refer to Figure 1). The region has a long history of copper mining dating back to 1923. The Copper Mountain camp occurs in the 'eastern volcanic belt' of the Nicola Group (Monger, 1989). It is an alkali copper-gold deposit in which the volcanic strata are intruded by early Jurassic dykes, sills, irregular plugs and zoned plutons (Woodsworth et al., 1992). The stratified rocks are relatively fresh with slight metamorphism in the local contact regions."

Jan 1, 2016

By N Meadows, M Rodriguez

A 200 000 tpa heap leach demonstration plant was approved by the Murrin Murrin Joint Venture (MMJV) in December 2005 and engineering commenced in January 2006. The demonstration plant will utilise stockpiled ore reject material (æscatsÆ) and extract nickel and cobalt. Limited production from the demonstration plant is expected by the end of 2006. The demonstration plant will enable the company to fully investigate and understand all associated technical issues over the next 12 to 18 months, including the potential to expand the heap leaching operation to a commercial scale. In parallel, the MMJV will continue a research and development program to improve and expand the application of its heap leaching technology.

Jan 1, 2006

By Edward A. Barrett, Kathleen M. Kowalski-Trakofler

This paper discusses the application of a training intervention that uses degraded images for improving the hazard recognition skills of miners. Method: NIOSH researchers, in an extensive literature review, identified fundamental psychological principles on perception that may be employed to enhance the ability of miners to recognize and respond to hazards in their dangerous work environment. Three studies were conducted to evaluate the effectiveness of the degraded image training intervention. A model of hazard recognition was developed to guide the study. Results: In the first study, miners from Pennsylvania, West Virginia and Alabama, who were taught with the aid of degraded images, scored significantly better on follow—up hazard recognition performance measures than those trained using traditional instructional methodologies. The second and third studies investigated the effectiveness of the training intervention at two mining companies. Data collected over a3—year period showed that lost—time injuries at mines in Alabama and Illinois declined soon after the training intervention was instituted. Impact on Industry: Further exploration of the hazard recognition model and the development of other interventions based on the model could support the validity of the steps in the hazard recognition model.

EARLY in 1911 the Public Service Board of New South Wales suggested the advisability of inaugurating a School of Mines at Broken Hill, arid made inquiries to determine how such an institution should be conducted. He, the author, believed the Board, as a result of the inquiries, was in favour of the project being worked in conjunction with the Technical College, and hoped to be ready to receive students at the commencement of 1912. That the inauguration has not yet taken place is probably due to the vast amount of consideration and preparation that a new departure of the sort would require. At the present time New South Wales or, to speak more broadly under the same denunciation, Australia is not at all suitably catering for the technical training of young men to provide the increasing demand for officers to work the valuable mines within its territory...

Jan 1, 1912

By S W. Houlding

The Certificate in Mining Studies program at the University of British Columbia, Vancouver, Canada is a collaborative initiative between mining schools and industry to provide accessible, cost-effective, accredited continuing education and training, designed to address the future needs of the global mining community. Content is provided by industry specialists and delivered through an integration of online learning, short courses and interactive webcasts. Accreditation is provided by a network of mining schools. In 2011, the program will deliver close to 100 short courses and interactive webcasts and provide 24/7 access to more than 130 online courses in six mining streams, to participants from as far afield as Tanzania, Argentina and Mongolia. The program is proving adaptable to corporate and mine site engineer-in-training and graduate-development programs, as well as providing accessible professional development opportunities for individuals. It also provides opportunities for cross-training from other disciplines and integration with mining school curricula.

Nov 22, 2011

By R. K. Sinha, B. S. Choudhary, Desh Deepak, A. K. Mishra, Hemant Agrawal, Shankar Kumar

There are several methods (empirical, statistical, and machine learning tools) to calculate blast-induced ground vibration. Still, due to complications in the blasting procedure, under varying blasting loads and strata conditions, it is not easy to predict and simulate blast vibration precisely. Therefore, a study was conducted to simulate the field blast data in Ansys software using explicit dynamics. For this study, monitoring of ground vibration for 20 single hole blasts was carried out. The density of emulsion explosives was in the range of 0.9 to 1.15 g/cc. In the laboratory, rock properties were determined from the rock sample collected from the mine site before blasting. The in-hole velocity of detonation (VoD) and the density of the emulsion explosive were also determined. These parameters were used for numerical analysis to know the ground vibrations at specified points. The results of ground vibration predicted by the model are validated using field data.

By Joan T. May

Federal Bureau of Mines studies showed that some organic amine hydrochlorides can be used as dehydrating agents for producing anhydrous magnesium chloride from hydrates and brines. Laboratory-scale tests showed that double salts are formed by reacting 35 percent magnesium chloride brine or spray-dried magnesium chloride with pyridine hydrochloride. Heating decomposed these double salts to anhydrous magnesium chloride and recycle pyridine hydrochloride. Pyridine hydrochloride also chlorinated any magnesium oxide in the spray-dried magnesium chloride. The anhydrous magnesium chloride obtained by the method described contained less than 0.8 percent oxygen. More than 98 percent of the organic amine hydrochloride was recovered.

Jan 1, 1978

The Effect of Molecular Weight on the Adsorption and Efficacy of Polysaccharide Depressants

Sep 13, 2010

By Robert B. Parsons

"Exploration and development of mineral resources in developing countries by Canadian-based multinational mining companies is becoming increasingly common. One problem being encountered is that the objectives of the governments of developing countries can differ from those of developed countries. These objectives are not always consistent with maximizing returns from the projects, which can create conflicts between the mining company's responsibility to its shareholders and the desire to be a good corporate citizen. This article discusses how a mining tax regime can be designed to make the social goals of a government consistent with the economic goals of the company.IntroductionAt the recent International Seminar on Mining Taxation organized by CIM and the United Nations there was considerable discussion about the role of international mining companies operating in developing countries. Not surprisingly, given the diversity of backgrounds of individuals attending the Seminar, there were different opinions about what this role should be.Government PositionRepresentatives of governments pointed out the strong desires of their countries for technology, high-level technical training of their workforce, increased employment, and development of social infrastructure. They pointed out that, to a large extent, these objectives could be more efficiently met by mining companies operating in the country than by the governments themselves. For example, a multinational mining company (""MMC"") would have extensive knowledge of the various technologies available, and would have performed a detailed evaluation of the mineral resources before choosing the most cost-efficient technology for that project. They would, therefore be in an ideal position to assist the country in importing and developing such technology. Similarly, the company could provide opportunities for hands-on training, both at the technical and managerial levels, which would otherwise be unavailable to the government."

Jan 1, 1991

By T. T. Chen, W. Petruk

The mineralogy of the feed, concentrates and tailings from the Heath Steele mill in New Brunswick was studied in detail to determine the liberation and recoveries of the major ore minerals, and to characterize the occurrence and distribution of the trace elements. The ore milled during August 1977 contained an average of 4.34 wt % Zn, 1.25 wt % Cu, 1.64 wt % Pb and 90 gr/ton Ag. The main trace elements in the ore are silver, cadmium, indium, cobalt, antimony, bismuth, arsenic, mercury, tin and gold. Silver is carried in solid solution in tetrahedrite-tennantlte, galena, Ag-Sb sulfosalts and Pb-Bi-Sb sulfosalts. Approximately half of the silver is recovered in the lead and copper concentrates and the remainder is lost in the tailings and Zn concentrate. As the major silver-bearing minerals also contain Sb and Bi, recovering silver by ore dressing would involve recovering elements that are troublesome in extraction metallurgy. Cadmium and most of the indium and mercury occur in solid solution in sphalerite and consequently are recovered in the zinc concentrate. Some indium is also recovered in the copper concentrate in a second unidentified indium-bearing mineral. Cobalt and arsenic occur principally in arsenopyrite, cobaltite, a Co-Fe sulfarsenide, pyrite and pyrrhotite, and follow these minerals into the tailings. Recovery of the valuable element cobalt, therefore, would involve recovering the environmentally hazardous element arsenic. Most of the tin and gold report to tailings. The ore was ground to about 80% minus 270 mesh. At this grind, 71 wt % of the sphalerite, 66 wt % of the chalcopyrite and 59 wt % of the galena were liberated. Recoveries of free sphalerite, free chalcopyrite and free galena in the Zn, Cu and Pb concentrates were 85 wt %, 76 wt % and 80 wt %, respectively; recoveries of unliberated sphalerite, unliberated chalcopyrite and unliberated galena in the respective Zn, Cu and Pb concentrates were 48 wt %, 5 wt % and 7 wt %. Some of the unliberated sphalerite and chalcopyrite grains in the tailings are large and would have been liberated at a finer grind.

Jan 1, 1980

Laboratory-Scale Magnetohydrostatic Separator for High Resolution Density Analysis of Plastic and Other Wastes Recycling and reuse of different plastic wastes is still a current problem to solve for process engineers and it is true for seeking industrial applications as well as for smaller laboratory-scale, where a given waste sample, plastic or even metallic, has to be precisely separated into narrow density fractions to gain data for industrial design or for scientific research. The principle of magnetohydrostatic separators are known even there are industrial size machines but our primary aim was the development of a laboratory-scale separator for analysis of particles of densities up to 6 kg/L and sizes up to 8 mm. Main parts of the built experimental equipment are the ferrite core with two high power coils. The shape of the ferrite core at the two sides of the separator channel was specially designed to produce isodynamic magnetic field. In these places the ferrite core was constructed from laser cut ferrite sheets. The development of the high power electric supply for the two coils was a real challenge because the high voltage and current (400 V, 30 A) and because it had to be precisely regulated for being able to set discrete relative forces on the particles. Two separator channels were made from transparent plastic. The magnetic fluid is circulated by a centrifugal pump, fresh feed is supplied by a vibrated feeder and products can be taken by built in samplers. The velocity profile in the separator channel is measured by an ultrasonic Doppler velocity meter. Paper reports about the development and itself of the magnetohydrostatic separator and about some fundamental and applied laboratory experiments with different reference particles and wastes from used cars and electrical appliances.

Sep 13, 2010

By J. A. Finch, Zhenghe Xu, Z. A. Zhou

Whether the microscopic bubbles generated by the high energy dissipation and high feed-slurry velocities in new flotation cells are stable in solution and what roles they play in particle collection are of great interest for the flotation of fines. Experimental work has shown that, with fast flow of liquid through an orifice, stable microscopic bubbles can form in flotation systems by hydrodynamic cavitation in the absence of gas supersaturation. The minimum flow rate at which bubble formation is initiated varies from 8 to 15 m/s, depending on the design of the cavitation tube, which is within the range of feed slurry velocities of some newly developed cells. Feed aeration enhances the formation of micro-bubbles by hydrodynamic cavitation. The study suggests that the fast flotation kinetics of some new cells may be attributed in some degree to the formation of microscopic bubbles

Jun 21, 1905

By A. Roy MacLean

"In the Maritimes, there are twelve coal areas. From east to west, these include the Sydney coal field, the St. Rose - Chimney Corner, Inverness, Mabou, Port Hood, Pictou, Colchester - Debert, Springhill, Joggins - Chignecto, Beersville, Lake Stream, and Minto. The first eight are in Nova Scotia while the remaining four are in New Brunswick.In all these areas, the coal was formed during the Carboniferous period, which existed some 300 million years ago. However, within this period not all coal formation took place during the same time. There were three main intervals, which occurred at the time that the Riversdale, Cumberland and Pictou groups were laid down (Hacquebard, 1970). The oldest coals are those of the Riversdale Group. These coals were of rather limited extent, and only a few mineable seams are present, particularly at St. Rose -Chimney Corner and Port Hood. From these two areas only 2 M tons have been extracted, and 'measured' resources of 7 and 9 M tons respectively remain. The Cumberland Group coals are confined to Cumberland County and include the coals of Springhill and Joggins River Herbert -Chignecto. Some 43 M tons have been removed and only 7 M tons of 'measured' coal remain, with an addit10nal 39 M tons of 'inferred' resources. However, there are additional resources at Springhill, which will be discussed in more detail in a later section. The coals of the Pictou Group are the youngest and the most abundant, both in actual number of seams and in regional distnbution. These coals were formed during the Westphalian C and D, a time during which the main coal deposition in Europe also took place. Here belong the coals of the Sydney, Inverness, Mabou, Pictou, Debert, Beersville, Lake Stream and Minto fields. Their total production amounted to 469 M tons or 91 % of the Maritime total of 514 M tons. The remaining resources of all Pictou Group coals have been calculated at 254 M tons of 'measured' coal and 949 M tons of 'inferred' coal. As can readily be seen, the bulk of both past production and remaining resources occur in the Sydney coal field. The Sydney figures represent 73% of total production, and 87% of total 'demonstrated' resources in the Maritime Provinces. Next to Sydney, the Pictou coal field has been the greatest producer, with 59 M tons; it also has the second largest 'measured' resources, amounting to 25 M tons. However in terms of 'inferred' coal resources, the Mabou coal field, ~ith 140 M tons, ranks second to Sydney."

Jan 1, 1985

By Alfred W. G. Wilson

In this paper is presented a review of the changes that have taken place in certain Canadian non-metallic mineral industries since 1909. The fifteen-year period 1909 to 1923, inclusive, has been selected for two reasons. In the first place, statistical treatment of the subject under review has been nearly uniform throughout the period. In the second place, this decade and a half is itself further subdivisible into three well marked quinquennial periods, the middle one covering the period of the great war when industrial conditions were greatly disturbed. It then becomes possible to institute certain comparisons between equal periods before and after the war disturbances. The items selected for inclusion in this review are certain of the more important members of that class of minerals usually grouped together under the heading of non-metallics. They are all minerals of which Canada is known to possess important resources, and which are indispensable to many of our greatest manufacturing industries.

Jan 1, 1925

By J. M. Ortiz

Grade control and short-term planning are usually based on the samples obtained from blastholes. These samples may carry a large sampling and sample preparation error. At El Tesoro copper mine in northern Chile, an advance drilling grid is used for short-term planning and grade control. These drill holes are sampled well in advance, and a short-term model that incorporates several variables and sophisticated estimation methods can be prepared for decisionmaking. An additional advantage of the advance drilling samples is that reverse circulation can be used instead of conventional down-the-hole equipment, and a very careful sampling and sample preparation process can be implemented, reducing the total sampling error. Advance drilling can be performed on a wider grid than blasthole drilling, hence the decision about the grid requires assessing the economic benefit of different sampling grids. Furthermore, this process allows the cost of poor sampling and the effect of different estimation procedures to be quantified. We demonstrate the optimization of the drilling grid for short-term planning and grade control at El Tesoro mine by means of the economic evaluation of the performance of different drilling grids, with different drilling techniques (which differ in the sampling error). The methodology is based on creating dense (exhaustive) geostatistical simulations of the grade distribution over a volume defined for a production period in respect of the geological model, and assuming each simulation as the true grade distribution. Then, samples are obtained from the exhaustive simulations at a spacing similar to the advance grid to be evaluated, and a sampling error is added. The short-term estimation procedures used on the mine are applied to determine the destination of each block and the profit obtained. This profit can be compared with the maximum profit (unachievable) and with the profit under different sampling errors and grids. The results show that the current 8 x 8 m drilling grid is appropriate and by reducing the sampling error, misclassification is also reduced, leading to an increase in profit of about US$ 5 million in 4 years.

Jan 1, 2012