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By The Staff

"IntroductionThe difficulties to be overcome in shaft sinking and development at depth are centred at McIntyre in and around No. 12 shaft. Generally they have been due to increasing pressures and temperatures and to changes in geological structure. This paper describes the difficulties and the measures taken to meet them.No. 12 ShaftEarly in 1932 McIntyre decided to sink an internal shaft from the deepest level, the 3875, to explore and develop known veins extending below that horizon. The location selected was a point 1,500 feet south and 1,000 feet east of No. 11 shaft, the main operating shaft through which the men, ore, and most of the materials are handled Shaft and auxiliary equipment we1e laid out for 3,000 feet, that is to 7,000 feet below the surface. The shaft was to be capable of handling 1,500 tons of ore daily from the lowest level, and was to provide ventilation, compressed air, water, and electric power to service all levels.No. 12 is an internal, vertical shaft extending from the 3875 to the 6825 level and bottoming at 7,007 feet. It is a rectangular, four-compartment shaft, 21 ft. 9¾, in. by 6 ft. 3¾ in. outside the timber (Figure 1).There are two hoisting compartments and one airway compartment, each 4 ft. 10¾ in. by 5 ft. ¾ in. inside dimensions, and a combined manway, pipe, and cable compartment 4 ft. ¼ in. by 5 ft. ¾ in. Levels have been established at 150-foot intervals, pump stations and sumps at 1,000-foot intervals, and. there are two loading pockets, one at the 5525 and the other at the 6900 level.The shaft was sunk in two stages. The first stage, consisting of preparation above the 3875 level and sinking to 5585 feet, was completed by March 31st, 1935. The second stage of deepening the shaft from 5,585 to 7,007 feet was started August lst, 1946, and completed three years later."

Jan 1, 1950

By F. Y. Grepe

"THE MOST common type of mine hoist is, as is very well known, that in which the a.c. wound rotor motor is the driving medium. The reasons for the use of the wound rotor motor are, of course, economic. This type of equipment has, during the years, proved to be very reliable and reasonably satisfactory. It is, in fact, still being installed and in some places where a very hard and exacting duty cycle is demanded. As an example, a 600 h.p. 2,300-volt job was recently installed at the Caledonia mine (1) at Glace Bay. This is a vertical. hoist in a shaft only 175 feet deep but it is, nevertheless, working hard bringing coal to the surface and in making a trip at a speed somewhat better than every 20 seconds.The control equipment for such installations usually consists of a pair of primary reversing contactors which are interlocked both mechanically and electrically, together with some form of secondary controller. This, in the case of small hoists, can be a drum controller and metallic resistors or, in the case of larger hoists, a magnetic contactor panel and metallic resistors or, alternatively, can be one of the various forms of liquid rheostats which are available. The liquid rheostats, if of the dipper type, may be manually operated or it may be operated by some form of servo motor mechanism. In the weir type of liquid controller, the electrolite is, of course, pumped in and out of the rheostat."

Jan 1, 1954

By Clifford S. Gibson

THESE troubled times suggest three reasons for maximum effort to control silicosis: (1) To keep to a minimum the ever-increasing burden occasioned by past deficiencies in this respect. (2) To effect the greatest production with maximum efficiency, which means at the least cost. (3) To preserve man-power in every way. Good control of the silicosis problem aids these aims. Inadequate control hampers all three. Insofar as our knowledge goes, silicosis in Ontario mines is caused by the inhalation of finely particulate quartz. It follows, therefore, that removal of dust containing this mineral automatically erases the cause. The achievement of this ideal is the aim of the mine operator. His best tool to this end is ventilation. This paper discusses mine ventilation from the viewpoint of dust control and it is hoped that in so doing there may result a better understanding of the part played by air in silicosis prevention. No attempt will be made to treat the subject fully. Instead, there will be presented certain salient aspects culled from field observations, the data in all cases referring to gold mines, unless mention to the contrary is made.

Jan 1, 1942

By Roger V. Pierce

IN the last few years, much study has been devoted to increasing stoping efficiency. The reasons for this are shortage of manpower, shorter working hours, operating regulations, and shortages of essential materials. More efficiency in mining methods is needed to offset these adverse factors. In the past, attention has been centred upon haulage, hoisting equipment, mill flow-sheets, etc., but recently the spotlight has been focused on the cost of stoping and the cost of handling materials. Scrapers and scraper hoists have thus assumed greater importance. In order to make it possible for certain orebodies to be mined at a profit, it has been necessary to apply assembly-line practices to the streamlining of mining methods. All cycles of the mining operation must balance, and the sooner broken ore is removed from the working face, the sooner another round can be started. Since the introduction of scraper hoists in metal mines more than thirty years ago, much progress has been made in their design and application. Alert operators are now constantly watching for methods in which to apply scrapers. The saving of manpower in development work and the changing of mining methods that once employed manual handling of materials are increasing vital wartime tonnages. Essential ores from newly discovered orebodies are moving rapidly from stopes to reduction plants-because it is now possible to develop an orebody and place it in production with a minimum of manpower and development work. Today, speed is one of the prime essentials o mining. Everywhere, there is a concentrated effort to use experienced miners in breaking rock, in timbering, and in carrying out the various phases of mining that require many months of training. Much effort is being made to mechanize the working places because experienced men naturally prefer to work where the majority of materials are handled mechanically. In line with this policy, many new men are being taught the details of scraper work, because even green men can quickly become acquainted with scrapers and thereby release older heads to perform the more skilled phases of mining.

Jan 1, 1943

By Min-Yuan Cheng

Heavy rainfall and typhoon oftentimes cause the collapse of hillslopes across mountain roads. Disastrous consequences of slope collapses necessitate the approach for predicting their occurrences. In practice, slope collapse prediction can be formulated as a deterministic classification problem with two class labels, namely ?collapse? and ?non-collapse?. Nevertheless, due to the criticality and the uncertainty of the problem, evaluating the collapse susceptibility of an area is a challenging task. This study proposes a novel Artificial Intelligence (AI) approach, named as K-Nearest Neighbor Based Bayesian Classifier (KNNBC), to deal with slope collapse assessment. In the proposed model, Bayesian inference is used as a framework to achieve probabilistic prediction of slope collapse. Meanwhile, K-Nearest Neighbor (K-NN) is employed as a density estimation technique. Equipped with probabilistic outputs, the K-NNBC is able to yield predictions with different levels of confidence and diminish misclassified cases. Experimental results point out that the proposed model is very helpful for decision-makers in slope collapse assessment and disaster prevention planning.

Aug 1, 2013

By E. J. Sides

In this paper, the argument is put forth that the codes used for public reporting of mineral resources and mineral reserves have some significant limitations with regard to the information provided to investors on the short- to medium-term value of mining properties. Such limitations include a) failure to explicitly incorporate a time element and b) failure to state explicitly the quantity and quality of mineral product that will be produced for sale. A time-value framework for reporting mineral assets is proposed in order to overcome these limitations. The proposed system is based on two classification axes: a) an X-axis representing time in years during which the value of the asset is likely to be realized and b) a Y-axis representing the value identified by a mining or exploration company\u2019s activities. The potential benefits of this system are discussed, including the ability to incorporate factors, such as permitting and construction times, directly into the magnitude of the reported mineral assets. The proposed framework would assist in the standardization of mineral assets reporting in such a manner that they could eventually be more readily included in financial statements. Year of Publication: Not explicitly mentioned in the document.

Jan 1, 2010

By C. Larsen, R. A. Walker, A. Voth, C. Daoust

"The 3000 t/d mill at Hernia Gold Mines Inc. was commissioned in March, 1985. By Canadian standards the concentrator is highly automated, however, unlike the retrofit systems in many other plants, the Hernia process control system was installed during plant construction. This paper describes the Hernia control system beginning with system development (justification, architecture, start up, etc.), proceeding to current applications (crushing, grinding, leaching, etc.) and finally discusses some of the short term objectives for system improvement.INTRODUCTIONThe Hernia Gold Mines Inc. operation is located in the Marathon area of Northwestern Ontario. Controlled by Noranda Minerals Inc. (50.1 %), the cost of bringing the mine into production was nearly $300 million. A unique feature of the mine development was the extraordinarily short elapsed time of three years from Noranda's initial involvement to the start of milling operations. Additional background information on this project can be found in the trade literature (e.g. Tinter (1986). Scales (1987).)The Hernia concentrator is designed to process 3000 tpd of ore and commenced operation in March, 1985. Figure 1 provides a general plant flowsheet indicating the major circuits. Typical annual production statistics are included on the figure and these have been extrapolated from the available 1987 year-to-date data. Larsen and Tessier (1986) have previously described the operational aspects of the mill.In a metaphorical sense, the Hernia concentrator is like the traditional bride, ""wearing something old (e.g. the cyanide leach process), something new (e.g. a plant wide digital control system installed during construction), something borrowed (e.g. crushers from Gaspe) and something blue (e.g. the cladding on the surface buildings). While the prospect of fully undressing this bride is of considerable interest, here we choose to focus on something new. In particular, we choose to examine the process control system in some detail since Hernia is one of Canada's more highly autcmated gold mills. The control system is of interest because it has received suostantial credit for maximizing metal production and minimizing operating costs. With reference to the latter, it is worthy of note that Hem lo reports recent operating costs of less than $100 U.S./oz."

Jan 1, 1988

By J. B. Morrow

Methods of Coal Preparation Fundamentally, the object of coal preparation is to increase, economically, the value of a fuel by making it more suitable to the uses of the consumer. This can be accomplished in three major ways: 1.Screening or sizing 2.-Mixrng or blending 3.-Cleaning By combinations of any or all of these methods we can prepare coal to meet standard specifications-a process of standardization which is the more desirable the more nearly it approaches the unvarying quality of packaged goods, where the package you buy today and tomorrow is the same as that you bought yesterday. It should be noted that it is readily possible to get good cleaning and still have poor preparation because of faulty screening and mixing, and, on the other hand, it is possible to get a passable grade of cleaning, combined with good screening and mixing facilities.

Jan 1, 1931

By S. Dessureault

The relatively recent explosion of available data in all business sectors has induced a common expression of “drowning in data, starving for information.” The mining sector is affected by the information age through equipment-based sensors, process monitoring, and traditional enterprise data sources. Information technologists have developed techniques such as data mining that apply new and old statistical algorithms to large datasets. Mine planners and managers can apply these tools for improved planning and control, thereby increasing the use of the highly underutilized information system infrastructure in most modern mines. This paper describes the use of data mining and its enabling technology, data warehousing, in the development of an energy consumption model for large surface mines using real historical data.

Jan 1, 2007

By Fadi Layyous Gedeon, David Hatton, Solomon Mogashoa, Tuhin Banerjee, Faisal Aljohani

The adoption of innovative technologies in mineral processing often raises concerns about complexity and integration. However, Woodgrove’s Direct Flotation Reactor (DFR) technology at Barrick’s Jabal Sayid copper concentrator provides a different perspective. This paper outlines the smooth integration of DFR technology from piloting to full-scale commissioning, showcasing how easily the cells were brought online. Installed in a cleaner scalper role, DFR cells at Jabal Sayid upgrade re-ground rougher concentrate to final concentrate in one stage. Despite processing challenging ore, the DFR cells delivered concentrate grades that consistently exceeded expectations. The commissioning process was straightforward with minimal hurdles, highlighting the technology's user-friendly nature. This paper advocates for a shift in perceptions about new technologies in mineral processing. The success of DFR technology at Jabal Sayid demonstrates that “different” doesn’t mean “difficult.” By focusing on ease of commissioning and operational integration, innovative solutions can enhance processes, improving efficiency and productivity in the mining industry.

May 4, 2025

By F. C. Grensing, W. R. Crib

Copper-15 Nickel-8 Tin alloy is a relatively modern material, having been discovered in the 1970’s. It has complexities with casting, hot working and interdependent solid state phase transformations. A key to the high reliability manufacture of wrought rods, bars, plates and tube is the casting technology, which limits segregation, promotes microstructural uniformity and enables hot working. The EquaCast® continuous casting process has enabled the production of a broadening variety of wrought forms with typical yield strengths ranging from 100 to 180 ksi (690 to 1241 MPa) depending on size, shape and temper. This paper reviews the characteristics of wrought Copper-15 Nickel-8 Tin products which have registration in AMS specifications (4596 and 4597) and MMPDS-04 (CN-1) for use in aircraft. The design limits, microstructures, fracture characteristics and tribological behavior will be examined. This alloy system is emerging as a material of choice for aircraft bearings, corrosion resistant oil and gas exploration components, machinery and demanding off-road equipment applications. ToughMet® 3 is an alternative or upgrade to conventional moderate and high strength aluminum bronze bearing alloys.

Jan 1, 2010

By V. D. del Valle, T. G. Joseph, J. J. Berezan

Aggressive driving patterns, rough and poorly maintained roads and pit floors, along with the occasional bump and poorly placed load from a shovel can create intense and sometimes serious vibration levels on a heavy hauler. The effects of high vibration have been shown to be of concern for the health of the operator as well as the reliability of the equipment. It is proposed that an onboard vibration warning system based on the ISO 2631-1 standard could be used to help operators reduce the vibration levels experienced in a heavy hauler. The onboard system would consist of a screen that displays the instantaneous vibration in the form of three lights: green (safe zone), yellow (cautious zone), and red (danger zone), as well as an overall vibration exposure or dose for the entire shift. With the utilization of the warning system, it is anticipated that the overall vibration levels will be decreased resulting in improved operator health, a reduction of vibration-induced maintenance, and improved haul roads through reduced impact loading and repair for localized trouble areas.

Jan 1, 2004

By Gillyeard J. Leathley

The Cassiar Asbestos mine is situated on McDame Mountain in northern B.C. at a mean elevation of 6000 ft (1830 m), some 6 miles (9.6 km) from the townsite /mill complex. Asbestos ore production averages 1,200,000 tons at 9% R.M.G. (Recoverable Mine Grade) and waste production is 6,000,000 cu. yd annually. Waste is loaded by P&H 1900 AL 11-cu.-yd shovels and transported by 75-ton and 85-ton end-dump trucks to the waste dumps. The ore is loaded by a 992 Caterpillar 10-cu-yd front-end loader into 50-ton and 75-ton trucks, which transport it to the crushing plant located at the mine. The ore is transported by a 15,370-ft (4685-m) tramline to the mill complex.

Jan 1, 1978

By R A. Stevenson

The purpose of this paper is to outline a recent development in ground fault protection. The paper deals with the A problems of both grounded and ungrounded systems, with regard to hazards to personnel and equipment, and shows that the increased sensitivity and speed of operation of this new detector results in increased safety to personnel and reduced stresses on equipment, and permits the detection of leakage currents before they become serious faults. The detector can be applied to all distribution systems, either A.C. or D.C., up to 15 kv., and the detector itself can be tested at regular intervals without interrupting line circuits. T HERE is always controversy among engineers as to whether distribution systems should be grounded or ungrounded. There are many experi-enced engineers on both sides of this controversy, and each have valid reasons for their choice

Jan 1, 1964

By K. Svens, M. Lahtinen, L. Lehtinen

"Outotec's direct leaching process is an atmospheric leaching process for sulphidiczinc concentrates. The direct leaching process, based on special leaching reactors developed by Outokumpu and leaching know-how, is the most economical way to produce electrolytic zinc. The newest industrial-scale application of Outotec's direct leaching process will be started up in 2008 in China at Zhuzhou smelter. The process isintegrated to the existing production plant, replacing part of the old production facilities by modern technology and increasing the production capacity significantly. The process equipment supplied by Outotec includes also tailor-made reactors designed on the basisof the work and experience of Outotec Research Centre."

Jan 1, 2008

By M. Yamine, R. J. Ring, D. J. Waters

"An experimental program has been carried out by the Australian Atomic Energy Commission to compare the effectiveness of Caro's acid as an alternative oxidant to pyrolusite in the leaching of uranium ores from the Alligator Rivers region of northern Australia. Batch leaching tests on Ranger, Nabarlek, Koongarra and Jabiluka ores showed that uranium extraction was unaffected by choice of oxidant, but that Caro's acid reduced acid requirements by 15 - 25%. Lime requirements for neutralization of tailings liquors were reduced by 20 - 30%.The batch studies were extended to a four-stage continuous leaching circuit with a capacity of 400 gore h-I. Comparative leaching tests confirmed the reagent savings obtained in the batch tests. Following these encouraging laboratory results, lnterox Chemicals Pty Ltd carried out plant trials using Caro's acid. Reagent savings in the mill were similar to, or better than, those obtained in laboratory test work. The trials also established that Caro's acid has a number of operational advantages over pyrolusite.IntroductionUranium is most commonly extracted from its ores by leaching in sulphuric acid. Simple hexavalent uranium oxides and compounds are readily soluble but uranium in the tetravalent form is insoluble and must be oxidized for dissolution to occur. The most commonly used oxidants have been sodium chlorate and manganese dioxide. They act indirectly by maintaining iron as the ferric ion which oxidizes uranium by a surface electro- chemical reaction. An Fe3+ concentration of about 1 - 2 g L-I is usually considered adequate for the effective dissolution of uraninite(1)."

Jan 1, 1984

By A. L. Karyakin

The report focuses on the process measurements of the mass of rock in the bucket power shovels and dragline excavators. The mathematical models are suggested of AC and DC electric drives of excavators. These models are a basis for calculation methods of the electric drive electromagnetic torque. The design schemes of mechanical equipment of excavators considered to account the situation of bucket in the plane of the boom. The methods of static moment allocation and identification of the excavator technological operations are developed. The results of the work are experimentally tested on power shovels with bucket capacity of 12 and 18 m3.

Aug 1, 2013

By T. Banerjee, R. deS. Almeida, D. Gudgeon, F. C. F. Batista, L. deÁ. Silva

"Yamana Chapada’s mine is one of the larger copper-gold mines in Brazil. The mine is located in Goiás state, in the central part of Brazil. The mine has estimated Mineral Reserves of 4.1 million ounces of gold and 3.2 billion pounds of copper as of December 31, 2016. While gold and silver are significant, Chapada’s process flowsheet is configured closer to that of copper facilities. This includes a SAG/Ball configuration for grinding followed by flotation. In the case of Chapada, the mineralogy results in higher-than-normal complexity, notably a significant circulating load both in the grinding and flotation circuits. From an operating perspective, the complexities are controllable, but require careful attention to ensure that circulating loads are effectively managed and gold is not lost to tailings. Chapada created an automation roadmap in 2016 designed to increase plant performance (tonnage, recovery and efficiency). Based on strong potential, the project was fast tracked and within 4 months instruments were installed, control algorithms implemented, and training sessions took place to ensure sustainability at site. This paper will follow the Chapada journey from identifying the opportunities through to implementation and testing.IntroductionYamana Chapada mine is a Copper-Gold mine located in Goiás State, Brazil. Although the mine contains large quantities in Mineral Reserve of gold (4.1 million contained oz as of December 31, 2016), Chapada is primarily a copper mine with copper principally found as chalcopyrite. Accordingly, the processing flowsheet at Chapada is comparable to that of other copper mines with a SAG and Ball mill each partnered with a cyclopack, followed by a flotation circuit. While the overall design is conventional, the mineralogy at Chapada results in significant circulating loads both in the grinding and flotation circuits. This does introduce certain complexities for operating strategies and practices, but, importantly, favourable recoveries and elevated processing rates can be maintained, albeit they need to be closely managed. Plant automation helps in this regard."

Jan 1, 2018

By L. B. Tsymbulov, L. Sh. Tsemekhman, A. N. Golov

Gipronickel Institute, JS is developing a process of continuous converting of Nicontaining copper matte and concentrates resulting in the production of blister copper and fluid NiO-containing slag in a two-zone Vaniukov furnace. The process under development is an alternative for the existing technology of blister copper production in converters, the latter being characterized with insufficient sulphur utilization, low direct copper recovery and the production of inconvenient for further processing solid slag on the basis of NiO and NiFe20 4- The results of pilot testing on processing of copper concentrate obtained from high-grade matte (HGM) separation in the two-zone Vaniukov furnace with the hearth area of 11.4 m2 are presented.

Jan 1, 2007

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