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By Moe Momayez

Shotcrete is a practical and economical support system in many Canadian underground mines. Although shotcrete technology has gained acceptance in the mining industry, there are some problems that have emerged with respect to quality assessment and thickness measurement of the liner. This paper presents recent tests performed with a miniature seismic reflection device developed primarily for thickness measurement of this heterogeneous liner. Work was performed on site in an underground mine in Ontario, Canada. This paper also presents the results from laboratory tests performed on fibre reinforced and non-reinforced shotcrete panels that were used to assess the P-wave velocity in both materials. The results of these tests were used in a second on site investigation. The NDT thickness measurements showed good agreement with direct thickness measurement such as coring.

May 1, 2001

By H. Salamanca

Recently, the mining industry has become one of the leading target markets for the technology industry as they need to innovate in their productive processes in order to boost productivity, reduce operation costs, increase operation safety, and improve the quality of life of their workers. This work presents the technological developments that HighService has done in different stages of the mining productive processes to include robotic manipulators in their automation solutions as well as the development of new equipment and sensors. The robotic technology integration is presented in different applications such as handling and selection of cathodes in E-W machines, automation of base plate maintenance, automation of cathode stripping machine, and multi-tools handler for liner bolt replacement in SAG mill liner maintenance activities. The proposed solutions show technical and economical viability with low initial investment and short implementation period of six (6) to ten (10) months. The results have been validated in plant, obtaining higher production rates and availability.

Jan 1, 2007

By B. Currie

Maintenance of quality electrowon copper requires an electrolyte which has suitable chemical and physical characteristics. The proper design and operation of the solvent extraction plant is essential to the quality of the electrolyte sent to electrowinning. An aspect that is not well appreciated is that the return electrolyte can have negative effects on the operation of the solvent extraction plant. Poor SX plant operation creates below optimum electrolyte conditions. High Eh in the return spent electrolyte can degrade the SX reagent with large decreases in copper transfer capacity and increases in internal entrainment. The synergistic interaction of the SX and EW plants needs a single-source design approach to address the interactions. The design elements in the SX and EW plants required to manage the electrolyte conditions are discussed.

Jan 1, 2014

By J P. Bolduc, P. E. Pelletier

Preceded by brief general considerations such as the development of the mining industry in. the Province of Quebec, the choice of plant location, the types of problems studied etc., the paper gives a complete description of this new research and treatment center for metallic, non-metallic and asbestos ores. Facilities for carrying out operations in the three sections of the plant -the sampling section, the ore treatment section and the asbestos section -are fully discussed as well as laboratory facilities for (a) the preliminary testing of ores prior to pilot plant treatment and (b) the grading and testing of asbestos fibre. AT THE beginning of the century, the annual value of the mineral production of the Province of Quebec stood at the $2,500,000 level. Twenty-five years later, it was just under $24,000,000. In 1950, half a century later, it was slightly in excess of $200,000,000. But in 1959, in the span of only nine years, it

Jan 1, 1962

By W. B. Morrey

This paper deals with the development of the new cap-sensitive slurry explosives. The history and special features of these explosives are outlined, and recent field trials are described.

Jan 1, 1973

By F. Roemer, D. Goldmann, T. Elwert

Tantalum is an important minor metal for the production of high performance capacitors. Approximately 60% of the annual tantalum production is used in this application. Despite its high price of 298 US$/kg (average price 2010–2014), at the moment, no recycling from end-of-life products takes place. In the established recycling processes of waste electrical and electronic equipment (WEEE), tantalum is lost in the slags of copper smelting, where it is highly diluted. An economic recovery is not possible at that point. Although tantalum must therefore be extracted from the WEEE stream before it enters smelting, no industrial recycling processes exist. The main reasons are its low concentration in the WEEE stream, lack of information about tantalum bearing devices, technical difficulties of extraction, and conflicts of interests regarding the recycling of other valuable metals in WEEE. In this paper, the results of a cooperation research project are presented. The aforementioned challenges are addressed and a novel tantalum recycling process is developed. Small pilot scale experiments show that a mechanical processing route can produce marketable tantalum-concentrates of 30% tantalum with yields between 60 and 70%. This is reached through a manual pre-sorting of potentially tantalum bearing products followed by a combination of an optimized comminution, sieving, air classifying, eddy-current (EC), and two stage magnetic separation. Key to the implementation of this process was a detailed survey of the tantalum concentrations in different products carried out by the industrial partner.

Jan 1, 2016

By M. Kreuh

An investigation of the pressure pulse spectrum generated by the gas dispersion processes in a Peirce Smith copper converter was undertaken via the simultaneous measurement of four tuyeres using high frequency pressure transducers. The data was captured, stored, and analyzed using digital data processing techniques; including power spectral density plots, band-pass filtering, and a principal component analysis (PCA). The process was characterized throughout by a dominant 3 Hz pulse signature attributed to the formation of lateral gas envelopes. In particular, test tuyeres in the tuyere line tended to operate synchronously at the dominant frequency, regardless of operating conditions tested and despite being distributed along the converter. Synchronous behavior is thought to arise from the acoustic coupling and possible resonance behavior of the gas delivery system on the converter.

Jan 1, 2007

By Jolanta Olkowska-Oetzel

Reactions of gold?phosphino complexes [(AuX)(PR3)] (X= Cl, Br, I; R = organic rest) with Se(SiMe3)2 lead to the formation of gold complexes with chalcogenide bridges. The reaction of the complex Ph3PAuCl and tBuSe(SiMe3) gives the cluster [Au5Se2(PPh3)4]Cl 1. The in situ preparation of the complex [(AuCl)2dpph] (dpph = Ph2P(CH2)6PPh2) by reaction of dpph with Me2SAuCl, and subsequent reaction with Se(SiMe3)2 leads to the formation of [(Au3Se)2(dpph)3]Cl2 2. Reactions of the gold(I) complex [(AuCl)2dpppe], (dpppe = Ph2P(CH2)5PPh2) with Se(SiMe3)2 and InCl3 in different molar ratios lead to the formation of [Au10Se4(dpppe)4]InCl5 3 and [Au4(SeInCl3)2(dpppe)2] 4. The reaction of [(AuCl)2dpph] with Te(SiMe3)2 and GaCl3 produces the isostructural cluster compound [Au4(TeGaCl3)2(dpph)2] 5. From the reaction of Se(SiMe3)2 with [(AuCl)2dppe] (dppe = Ph2P(CH2)2PPh2) and InCl3 [Au8Se4In(dppe)4](InCl4)3 6 can be isolated. The structures of 1 - 6 were determined by X?ray diffraction.

Oct 1, 2003

"Successive seismic waves may cause progressive weakening of a fault zone, which has been recognized as the mechanism of earthquake aftershocks. However, it is unclear that how a fault zone slips under each wave cycle and how slip displacement accumulates under continuous wave cycles. This laboratory study provides direct evidences on the slip process of a simulated granular fault zone dynamically induced by an incident wave without the effects of late-arriving and reflected waves. The experimental observations show forward and backward slip paths of the fault zone and partially recovered slip displacement after a wave incidence. The unrecovered slip displacement after each wave cycle can be accumulated until it reaches a critical slip distance for seismic faulting, which may reinterpret delayed triggering in earthquake dynamics. The limited interseismic period restricts fault self-healing in strength. The experimental results also indicate that the dynamically induced frictional slip on the fault zone is associated with a complex frictional system, including seismic wave radiation, frictional slip initiation and normal stress vibration. Different from the dynamically induced frictional slip on the fault zone, the statically induced frictional slip causes a permanent increase of slip displacement along the shear loading direction. INTRODUCTIONAn earthquake mainshock may induce aftershocks by suddenly changing external stresses applied to another fault zone in the near field (Kilb et al., 2000) and by slightly perturbing a fault zone from a critical steady state to stick-slip faulting in the far field (Gomberg and Davis, 1996). The dynamically induced frictional slip on a fault zone has been recognized as the mechanism of earthquake aftershocks (Marsan and Lengliné, 2008; van der Elst and Brodsky, 2010). Although earthquake aftershocks have been extensively studied by many seismological methods, a simplified laboratory fault zone can provide possible interpretation on real faulting and detailed analysis on a friction process (Dieterich, 1979; Nielsen at al., 2010). According to a few laboratory experiments related to the dynamically induced frictional slip on a simulated fault zone (e.g., Uenishi et al., 1999; Johnson et al., 2012), the slip process induced by successive seismic waves exhibits continuous motions. However, it is unclear that fault slip response under each wave cycle and slip displacement accumulation under continuous wave cycles."

Jan 1, 2015

By E. Godfrey

The average man one meets on the street thinks of an explosive as a medium of death and destruction, something unstable which should be given a wide berth, because he knows little or nothing about its use or its stability. Briefly, explosives are compounds that develop very large quantities of heat and gas in an extremely short time and in a small space, thereby exerting enormous pressure upon surrounding bodies, and by the rapid expansion of this highly heated gas are able to perform a considerable amount of useful work. The amount of heat generated and the volume of gas produced by the decomposition of an explosive determines the amount of mechanical work it can do, and the time occupied by its change from solid or liquid condition to gaseous condition determines its shattering effect. Explosives manufactured by reputable people are not extremely dangerous, on the other hand they are quite safe if handled in a proper manner. Furthermore, before an explosive can be placed on the Canadian market a sample must be submitted to the Explosives Division of the Mines Department, who may condemn or permit its manufacture, according to their findings regarding its safety in handling and its stability during storage.

Jan 1, 1926

As land resources decrease, commodity prices increase, and technology evolves, deep sea mining is becoming a viable alternative to meet the increasing demand for minerals. Successful deep sea mining operations are built on sound identification of the resource, proper selection of equipment, a thoughtful production plan, and good project management. These four key activities can be further optimized by analyzing how the spatial variability and uncertainty of the ore body properties impact the final mining operation. To address this problem, IHC Merwede is in the process of developing a risk quantification framework in the context of deep sea mining, which makes use of state of the art geostatistical simulation methods and transfer functions to quantify geological uncertainty and translate it into decision or project risk. The paper introduces the Local Average Subdivision method (LAS) for generating simulated models of the deposit and presents a new extension to incorporate point measurements of geotechnical or ore grade properties. Due to its computational efficiency, the presented method is suitable for simulating largely extended sea floor deposits. The second part of the paper illustrates, through example case studies, the significant benefits of a risk based approach which translates geological uncertainty into financial or operational performance indicators. In particular, the focus is on assessing financial project risk and on the design optimization of the deep sea excavation equipment by analyzing cutting forces, specific energies, and power requirements.

Aug 1, 2013

By R. H. Waddington

Historical The limitations of reverberatory furnace operation have prompted many investigators to consider electric furnaces for melting electrolytically refined cathode copper. In the majority of cases where experimental work was performed, the furnace used was of the granular resistor, induction, or indirect-arc rocking type, and attempts to adapt the three-phase direct-arc furnace to copper melting appear to have been relatively few. In 1935, the International Nickel Company of Canada, Limited, carried to an advanced stage its experimental investigation of continuous melting of copper in the three-phase direct-arc furnace, and demonstrated that this process was technologically and economically practicable. Trial operations were conducted at the Huntington, W.Va. works of the Company, and were followed by the installation at Copper Cliff, Ontario, in 1936, of a full-scale unit for commercial operation. Two years later, a second unit was installed -which raised the electric melting capacity to a point permitting complete replacement of the coal-fired reverberatory furnace operation in the production of refined copper castings.

Jan 1, 1946

By J. A. H. Church

My paper entitled "Spontaneous Combustion of Coal in Mines;" read some time ago before this Branch, consisted chiefly of extracts from the British Blue Book dealing with the same subject. Fallowing my article, Mr. de Hart submitted a paper dealing with the application of existing methods of working in Alberta to the conditions obtaining in our bituminous mines. I must confess that the perusal of his paper did not enlighten me either as to what might be a method preferable to those in vogue or even to Mr. de Hart's ideas on the subject, nor did the ensuing discussion of Mr. de Hart's paper afford any great clarification of the problem. The outstanding idea, supplied by Mr. Dick, seemed to be that a retreating system could not be employed, as no operator would feel justified in risking the capital necessary to driving to the boundary when the whole might be jeopardized by a fire breaking out in the waste. That a fire would break out in the waste of any adit-level working seemed to be conceded by all, and with that I agree; that an ignited waste could not be safely sealed off by means of stoppings in a coal barrier-pillar appeared to be the contention of Mr. Dick, or perhaps he attributed this idea to the Mines Branch-anyhow, it seemed to loom over the discussion like a miasma. With this aspect I do not agree, as ? reliance is placed wholly on stoppings in the thick seams of South Staffordshire, even in fiery mines. In the thick coal at Exhall colliery, or elsewhere in Warwickshire (34 feet 4 inches) containing hard and soft coal in layers, a fire assuming serious proportions is sealed off. By the way, retreating long-wall methods are employed. In Fifeshire, sealing off fire in the Dysart mine has been accomplished successfully. The seam averages about 20 feet thick.

Jan 1, 1924

By J. E. Rehder

IN A DISCUSSION of use of any material of ?construction in the mining industry, two points of view must 'be kept in mind - that of the producer or manufacturer of mining and metallurgical equipment, and that of the maintenance and operating staff of the mining plant. In the first case, the choice of material of construction is up to the manufacturer and the user of the equipment has little direct say in the matter. However, if materials are badly chosen and the equipment does not function properly, wears out rapidly, or costs too much, repeat orders ?will likely go to a different manufacturer, so that, in the end, the consumer or mine operator does have the final voice. In the case of materials for maintenance work and plant operations, however, .the mill personnel have direct control over purchases and it is then that a well-balanced knowledge of materials, their properties, and their costs, can be directly useful. With all materials of construction, the final criterion is unit cost versus service performance, so that the lowest possible total operational cost will be obtained. Sometimes this means using the cheapest material available, sometimes the most expensive, but in any case careful analysis of service performance, replacement cost, and material cost is essential to determining the material that produces lowest total cost.

Jan 1, 1956

By Gordon G. Duncan

Historical Sketch Occurrences of native copper have been known along the Arctic coast of Canada, especially in the vicinity of the. Coppermine river, since the early part of the eighteenth century (See map, Figure 2, insert). In 1769, Samuel Hearne, a clerk of the Hudson's Bay Company at Fort Churchill, was sent to explore the 'copper mines' from which natives had been reported to secure copper for tools, fishing spears, etc. After two successful attempts, he reached the Coppermine river in 1771, accompanied by Indian guides. This hazardous trip was indeed a remarkable feat when one considers the vast distance covered, a great deal of which was barren lands. At Bloody falls, (See Figure 1) on the Coppermine river, Hearne's Indians swooped down on a party of sleeping Esquimaux, who gathered there each summer to fish, and murdered the entire band encamped on that side of the river. Hence the name of the falls. Hearne's knowledge of minerals was undoubtedly limited. He reported having seen the copper mines from which the natives were securing the copper, but he failed to prove the economic possibilities of the copper occurrences or to give an accurate description of any deposit. Sir John Franklin visited the area in 1821. He and other members of his expedition, namely, Richardson, Back, Kendall, and Hood, reported native-copper float to occur in the vicinity of the Coppermine river and Bathurst inlet.

Jan 1, 1931

By Luke Meers

Roadway development rates in Australian underground coal mines are failing to keep pace with modern longwall systems and are unlikely to sustain further improvements in longwall productivity into the future unless step change improvements to roadway development equipment and practices are made. Bottlenecks which limit and constrain improved production and impact the safety of operators have been identified through a series of industry surveys, with the manual installation of strata support materials, consumables delivery, coal haulage and monorail installation being highlighted as major areas to improve development performance. This paper looks at research being carried out at the University of Wollongong in designing an integrated system approach for the fully automated handling and installing of development consumables, and the systems required to support these activities. A series of hard automation manipulation devices have been demonstrated in surface trials and the results indicate that rapid roadway development can be achieved.

Aug 1, 2013

By John A. Allan

Introduction There are times when meditation on the past is worth while. Too often does it happen that in the busy routine there appears t9 be little time for reflection, and little good or benefit to be derived from what has already taken place, or what has become past achievement. Under conditions such as those that prevail at present, consideration is being given to many subjects that a few years ago were not looked upon as worthy of time or thought. The temporary lull in industrial development is permitting of a stock-taking investigation, a perusal of past activities, and a planning for future development with the return to normality. It is not proposed to include much new data in this address, but the endeavour will be made to survey, in resume, the sequence of events which led up to the birth of the mining industry in Canada, and to show how, as new discoveries were made, the centres of interest changed from time to time until mineral development extended across Canada from the Atlantic to the Pacific. It will appear, also, that external causes have accentuated mineral development at one time and retarded it at another. Early Records A, historical background to the mining industry extends even to an earlier date than the discovery by white men of that part of the continent of North America represented by Canada. It has been stated that the aborigines were still in the neolithic stage when the white man arrived. One metal only was known to the natives, and that was copper, obtained from possibly many parts of Canada, but particularly from the shores of lake Superior in Ontario, from the Coppermine river on the Arctic coast, and from die coastal regions of British Columbia.

Jan 1, 1933

By Andrew Barnes

The adsorption capacity of peat collected from a proposed mine development in northern Sweden has been determined using laboratory column experiments in which peat was irrigated with a simulated (acidic) waste rock dump leachate. The simulated leachate was made using a hydrogen peroxide leach of composite waste rock from the proposed mine development. The waste rock samples were composited in proportion to their predicted extractable tonnage for the mine development in order to generate a more representative leachate solution for the waste rock facility. As expected the test revealed that the peat material shows a very high affinity for attenuation with greater than 70% of Co, 90% of Ni and 95% of Cu removed from influent solutions through the majority of the tests demonstrating the potential benefits in mine water treatment. In contrast, it was found that Fe is initially released from the peat at concentrations up to 100 mg/L and can mean potential problems for the water released depending on the receiving environment. The exact mechanisms for Fe release is uncertain, though it is suspected that ion exchange / competitive desorption is responsible. Inspection of the laboratory results and drainage data from the natural peat wetland receiving drainage during overburden prestriping and mine development at the mine site are comparable, confirm the validity of the experiments, and further emphasize the potential for future use of pre-stripped peat material in managing water quality.

Aug 1, 2013

By I. V. Kojo

Continuous development of technologies has been self-explanatory for Outokumpu Technology's engineers for decades. The aim in the development has always been the improvement of profitability of the copper production but also the sustainability of the processing i.e. high copper recovery, low external fossil based energy utilization, high emission captures and of course low operation and investment costs. Outokumpu Technology's long-term view of the development is a change towards continuous processes and elimination of number of unit operations in smelting i.e. elimination of possible sources of emissions. Outokumpu blister smelting processes i.e. Outokumpu Direct-to-Blister Flash Smelting and Kennecott-Outokumpu Flash Converting have shown excellent operational results during the years of operation and it is expected that soon more than 10 % of the world primary copper is produced by these technologies. The paper will give some background of this development trend.

Jan 1, 2007

By A. J. Pearce

MOST mines have a model of some kind to illustrate either geological structure, mining operation, or some special condition or feature of the property. The type used depends on the particular feature or use for which it is intended. At Dome Mines we have developed an interesting and practical application of the horizontal-type model. This model shows the workings of each level horizon plotted on glass. These glass panes are set in frames which, in turn, rest on drawers equipped with rollers which can be pulled out as desired into a light chamber. The features of this model are its rigid steel construction and that any desired number of level plans can be pulled out, eliminating any other interference from other levels. Figures 1 and 2 are photographs of the model cabinet and show its construction and general features. The cabinet is of steel construction with the following overall dimensions: width, 6 ft. 5 in.; depth, 6 ft. 7 in.; height, 5 ft. 2 in. When not in use it can be completely closed-in, making the cabinet practically dustproof. There are 30 drawers, one for each of the 29 levels and one for the surface. The glass in each drawer is divided into two panes, 36 in. by 36 in., of flatdrawn double-diamond 'lustraglass' with about l/32 in. between adjacent edges. The panes are held rigidly in the frames, which are lined with felt strips, and may be adjusted by set screws, four of which on each drawer are shown in Figures 1 and 2. The level workings, on a scale of 1 inch equals 100 feet, are traced in ivory black Windsor & Newtons artist oil paint. Co-ordinate lines are shown in crimson lake, and main geological contacts are shown in their respective colours. Figure 3 is a photograph looking down on one of the levels. The lighting consists of 14 30-watt fluorescent bulbs, with reflectors, under frosted glass. These lamps are much more satisfactory when operated by 60-cycle rather than 25-cycle and, as we had available nearby a source of direct current, this was used. The electrical unit consists of a rotary converter from d.c. to 60-cycle. This arrangement gives perfect lighting, allowing most colours to be easily distinguished. Figure 1 was photographed using this source of light, Figure 2 using an outside floodlight.

Jan 1, 1945