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By C. S. Parsons

Introduction Up to the present, the operation of small mills for the treatment of gold ores has not been favoured in Canada to the extent that it has in other countries. For instance, a list of the operating properties in Southern Rhodesia, published in The Rhodesian Mining Journal of November, 1934, shows for the month of September, 1934, that there were over 500 small mills treating less than 50 tons per day, and the majority of these between 5 and 25 tons. They are operated by individuals, syndicates, and small mining companies. It is presumed that the operations are profitable, although from the published figures of the tonnages treated and the yields, it is difficult for one familiar with Canadian operations to understand how this can be possible, in the majority of cases. Most of these small mills employ stamps with plate amalgamation and with, occasionally, tables to produce a concentrate. Enquiries have been received from many parts of the world respecting milling practice suitable for small gold mines and the type of plant used in Canada. The tenor of these enquiries leaves the impression that the majority of the writers assume that the practice would be similar at all small properties. This, of course, is not the case. Conditions vary widely, and what would be a suitable mill for a typical Nova Scotia ore would not necessarily be wholly adaptable to many ores in Ontario, Quebec, or British Columbia. This paper has been written with the intention of inviting discussion, and it is hoped that, by such discussion, the subject will be more fully dealt with than has been possible in the time at the disposal of the writer. Only more or less standard principles and practices have been dealt with, and, purposely, no reference has been made to plants using mills of the Hadsel, the Nutt, or the Gibson type. As there is available but little reliable information on the costs of installation and operation of small mills, it is also hoped that those contributing to the discussion of milling practices for small mines will be in a position to give these data for the benefit of those contemplating the erection of small plants in Canada. Although it is difficult to generalize, it can be said that there are three types of gold mills commonly used at small mines: (1) Amalgamation and Gravity Concentration; (2) Amalgamation and Flotation; and (3) Cyanidation.

Jan 1, 1935

By Jessica Barber

Problem ? Mining operations consistently need equipment that is available, and able to perform to its maximum potential ? The most difficult part of a Maintenance Manager?s job is often a lack of knowledge on how long their equipment has to last ? The short term view can lead to interim fixes that accumulate into larger problems ? It is always difficult to justify major overhauls and upgrades when there is pressure to meet mine plan production targets

May 1, 2008

By R. C. Tait

The gold at Giant Yellowknife is intimately associated with a complex mixture of sulphides, including pyrite, arsenopyrite, stibnite, and a wide variety of antimony sulpho-salts. Direct cyanidation has never been feasible. Recovery is almost entirely dependent upon flotation, roasting of flotation concentrate, and cyanidation of calcine. In November 1958, an Edwards-type roaster and an early prototype, two stage Fluosolids roaster, were replaced by a large two-stage Fluosolids roaster of improved design. The new roaster was started at "safe" medium temperatures, but early in 1959, temperatures in both stages were gradually and deliberately lowered to determine whether continuous autogenous roasting could be maintained under exacting low temperature conditions necessary for good extraction. Operation is smooth and continuous with first and second stage temperatures controlled at 925° and 875°F respectively. Plant cyanide ex-traction compares very favourably with extraction from low

Jan 1, 1961

By J. Shanks

A S far back as 1925, Brazeau Collieries, Limited, became interested in .briquetting. This was brought about by complaints from their principal customer that stack losses, due to a high percentage of fine coal in their mine run, were excessive. The Company considered oil spraying of the fines. This, after some experiments and tests had been made, was ruled out as uneconomical and impracticable. When sufficient oil to be effective was put into the fines, it caused the coal in the tender of stoker-fired engines t0 arch over the screw feeder. The Company ultimately placed their problem in the hands of the Re-search Department of the University of Alberta. Experimental work was carried on by this department over a period of more than a year. The results obtained and the experience gained in this research work were conveyed to Brazeau Collieries in a report dated October 31st, 1929, and in a supplementary report dated February 2nd, 1935. Most of the results obtained in experimenting with Brazeau coal are embodied in a brochure, reprinted from the proceedings of the Second International Conference on Bituminous Coal, Vol. 19-24-28, entitled Principles in the Briquetting of Coking and Non-Coking Bituminous Coals, by E. Stansfield and W. A. Lang. All who are interested in briquetting should read this brochure. In the writer's opinion, iris the most important treatise on the subject printed in recent years. The results given in the paper are, of course, those obtained in laboratory investigation. It was pointed out to the writer that it would be most interesting to have such results correlated with those obtained in commercial practice. In this short paper, an attempt is made to do so.

Jan 1, 1942

By N. Samman, S. N. Lau

"A series of new, grease-based, solvent free open gear lubricants were developed to meet the demanding service requirements of mining equipment. The use of these products has resulted in better performance under conditions of temperature extremes and in terms of longer component lives. They have gained widespread acceptance within the mining communities for such applications as the lubrication of mining shovels, draglines and ball mills.These products are WHMIS non-controlled and are environmentally acceptable. The benefits and advantages of using this type of product to lubricate mining equipment as well as the field evaluation and experience will be discussed."

Jan 1, 2002

By D. A. Temple, G. O. John

Until recently, the approach to the problem of treating complex ores bas been to produce, insofar as is possible, mono-metal concentrates which are treated in traditional zinc, lead and copper smelting circuits, with the residues and by-products from some of these circuits being retreated for the recovery of contained values either by a separate residue treatment process or along with the primary feed to the appropriate circuit. The continued development of the Imperial Smelting Process, with its ability to treat poly-metal concentrates, calls for a re-examination of the traditional approach to this problem, and this the paper attempts to do. A survey of recent progress in the technical development of the process is made and a summary of current operational performance is included.

Jan 1, 1971

By J. Elderton

"The combination of A C induction motor and flu id coupling, of either the fixed or variable filling type, constitutes a simple, low cost, highly reliable drive unit, with many applications in the mining field.The paper will, however, concentrate on the variable filling fluid coupling in three principal applications-conveyor starting, infinitely variable speed control for slurry and slimes pumping and dewatering pumps for deep mines. Fluid couplings can be used with standard or custom-built control gear equipment, ranging from the most simple, time-based open loop types, to those having the latest microprocessor techniques.IntroductionThe first industrial applications of fluid couplings included their use in the mining field as hydraulic slip regulators for flywheel generating sets. These installations, usually rated at around 1700 to 2500 hp, were located at mine shafts where the electrical grid transmission lines were not strong enough to cater for the peak power demands of the cage winding cycle. In Canada, the first two significant examples of variable filling fluid couplings for mining were on conveyor drives, at Steep Rock Mines Limited, closely followed by the major iron ore handling term inal on the St. Lawrence River at Sept-Iles. Successful and reliable operat ion of the fluid couplings at these two sites set the pattern for use on many subsequent mining projects throughout the Canadian Continent."

Jan 1, 1986

By William Petruk

Image analysis studies were performed on mill products from pilot-plant and laboratory tests that had been conducted to determine the effect of grinding media on the selective flotation of two zinc-lead-copper ores. It was found that, when the ores had been ground to the same degree of fineness with flint pebbles, ceramic pebbles or ore fragments (autogenous grinding) as with steel balls, there generally was increased sphalerite, chalcopyrite and galena liberation in the flotation feeds, depending on the textures of the minerals. The increased sphalerite liberation fully accounted for the improved zinc recoveries that were obtained when steel balls were replaced by either pebbles or ore fragments. The increased chalcopyrite and galena liberation accounted for part of the changed technical efficiency of concentration, but other factors, probably changes in oxidation and reduction of iron and in consumption of oxygen, also contributed.

Jan 1, 1977

By T. A. Grammatikopoulos, B. Vasily, A. H. Clark

"The St. Lawrence deposit is a large wollastonite skarn (ca. 9 Mt @ 41.3% wollastonite) adjoining the gabbroic-to-syenitic Leo Lake pluton in the granulite facies Frontenac Terrane of the Grenvillian Central Metasedimentary Belt. It occurs within a horseshoeshaped horizon of quartzite, open to the east. The skarn extends over 1.2 km2, and comprises wollastonite-dominant, wollastonite-clinopyroxene, and diverse quartz-feldspar-sulphide (-titanite) layers, interbanded with, and strongly folded within, the quartzite. As in the world-class wollastonite deposits of the Willsboro district, New York, no carbonate protolith is preserved, and calcite is a negligible constituent of the mineralized zones. Wollastonite development is nonetheless ascribed to metasomatism of a metacarbonate unit by magmatogene, silica-rich, CO2-poor (XCO2 < 0.05) fluids, at P = 350 MPa and ca. 560°C, or, alternatively, 550 MPa and ca. 630°C.Several high-grade zones, averaging >40% but locally exceeding 80%, of translucent, white, tabular wollastonite grains, with lengths of 0.2 cm to 5 cm, have been delimited by drilling. Preliminary beneficiation studies yield high aspect-ratio and high-purity (low Fe and Mn) concentrates.St. Lawrence compares favourably to other known prospects and operating wollastonite deposits: having good chemical and physical properties, low iron content, and high aspect ratios (>20:1). In addition, the deposit has a favourable size and location, and will benefit from a low Canadian dollar. Canada currently has no wollastonite production."

Jan 1, 2003

By K. V. Konigsmann

"Mattagami Lake Mines Ltd operate a zinc-copper mine with an annual output of about 200,000 tons of zinc and 30,000 tons of copper concentrates. Zinc concentrates arc shipped to a company owned smelter in Valleyfield (a distance of 690 miles), for Export to Quebec City and also to Josephtown, Pennsylvania (1,060 miles, Figure 1.)The protection of concentrates in open gondola rail shipments has been a matter of concern since operations commenced. Considerable financial losses did occur at times because of wind erosion. Operating difficulties were also encountered by customers because of excessive moisture accummulation in the concentrates. Test shipments made in 1969 established the magnitude of losses in open cars. The results and subsequent investigations at our mines and elsewhere confirmed that load protection is an economic necessity.Many types of covers were experimented with, more or less successfully. In 1972 we agreed on a joint program with Dupont of Canada Limited. A new type of cover was developed by early 1973. It has been in use since, undergoing several improvements as experience accumulates."

Jan 1, 1975

By Christoph Mueller

Broad band mine communication today is characterized mainly by individual solutions, which have in common their long development phases and their high cost for development, operation and service. The use of Ethernet and TCP/IP on the other side provides an uniquely price efficient combination of high bandwidth open networking, universal use and accessibility of cheap development tools, especially because it forms the technical infrastructure for the worldwide Internet. TCP/IP and Ethernet assures reliable networking however it is not able to guarantee the latency timing of forwarding network information. Therefor, the network design requires strict load limitation and application level traffic control especially if moving equipment has to be manually remotely controlled via the network. To optimize the use of bandwidth on mining networks using load limited, ?bandwidth wasting? local Ethernet segments, long distance broadband traffic should be carried out using more efficient, deterministic communication backbones providing a guaranteed quality of service for each of the physically separated networks. Open networking and broadband systems however may lead to the anticipation that any demands on bulk data or multimedia traffic can be fulfilled in the future. This definitely will not be the case as the bandwidth demands of applications will be growing as least as fast as the bandwidth provided by communication systems. Looking on those problems from an overall system integration perspective, machines and equipment in the future have to be equipped with intelligent computing devices capable of an intelligent local data preprocessing. Such ?Embedded Machine Information Servers? running commercial computing power in the future will be the intelligent bridge between open networking and a secured, high safety local automation system. These ?Embedded Machine Information Servers? then also can make advantage of intelligent video and audio data preprocessing to store and transmit multimedia information ?on demand? or when the application requires it. Summarizing the potential for the future Ethernet based networking together with powerful communication backbones and intelligent local data preprocessing on the machines in the future will lead the way to integrative, reliable and cost efficient mine automation solutions.

May 1, 2002

By J. Poplawski

In mineral processing plants, cyclones typically perform the classification duty prior to the downstream recovery process. Particle size distribution of the cyclone overflow is an important parameter and can be viewed as the product of the comminution process. Too coarse of a product will likely have poorly liberated valuable minerals and make recovery difficult. Too fine of a product may represent a missed opportunity to increase plant throughput and/or also result in low recovery due to poor kinetics. “Near-line” particle size measurement instrumentation has been in place for several decades, its availability and low measurement frequency have typically been inadequate for reliable use in automatic control. CiDRA Minerals Processing has developed a novel and robust technology that provides a highly reliable and low maintenance system for “on-line” measurement of the particle size in the overflow of individual cyclones. The system is based around a wetted sensor design with no moving parts and provides a real-time trend of the desired target grind size parameter. The system does not require sampling and associated sample transfer piping that is prone to plugging, thus avoiding high maintenance requirements. Plant data and benefits realized from the latest installations of the CYCLONEtrac PST will be presented. INTRODUCTION Impact-based real-time hydrocyclone particle size measurement Acoustic impact-based particle size tracking is a unique method for measuring and controlling the particle size in cyclone overflow streams. The implementation of this technology is centered upon a sensor probe that is inserted into the overflow slurry stream via a two-inch (50 mm) hole in the overflow pipe (Figure 1). Particles within the slurry stream impact the surface of the probe generating travelling stress waves within the probe. A sensor converts these travelling stress waves into an electrical signal and proprietary signal processing techniques convert these signals into a particle size measurement that is output every four seconds. The sensor is constantly in contact with many particles in the slurry stream, thus obtaining information from orders of magnitude more particles than traditional sample-based technologies. The sensor has no impact on cyclone performance because it is located downstream of the hydrocyclone and the presence of an air core ensures there is no change in the back pressure seen by the hydrocyclone.

Jan 1, 2019

By I. I. Betcherman

INTRODUCTION A DISTILLATION process offers one of the most effective methods of refining metals. Its use is particularly attractive in the case of reactive metals which are not readily treated by pyrometallurgical or electrolytic methods. The 1ow vapour pressure of most metals severely restricts the applicability of the disti1lation process and only one or two metals may be effectively treated under atmospheric pressure at a reasonable temperature. If operations are carried out under reduced pressure several additional metals may be effectively distilled. Table I shows the vapour pressure of a number of metals together with a value of the free energy of formation of their ?oxides. Zinc and cadmium head the list and for many years? they have .been effectively refined by distillation. Sodium, magnesium, and calcium follow in descending order, and they may be distilled readily in vacuo and with difficulty at atmospheric pressure. Sodium, which is not of great metallurgical interest, is not considered. Magnesium has recently been produced in considerable tonnages by distillation methods ( 3). This paper describes the vacuum distillation of magnesium and calcium, their separation from each other, and their separation from less volatile impurities.

Jan 1, 1951

By A. F. Banfield

"IntroductionELEMENTAL sulphur occurs in three types of deposits: in salt domes in the Gulf Coast region of the United States and Mexico, from which over 90 per cent of world native-sulphur production is obtained; in sedimentary deposits such as those in Sicily, which are thought by some authorities to contain the largest world reserves of elemental sulphur; and as surface deposits, associated now or in the past with some phase of vulcanism, the type which bas the greatest world-wide distribution.Deposits of the volcanic type are the subject of this paper.From antiquity until the successful development of the sulphur-bearing salt domes at the beginning of this century, important sulphur production for local needs was obtained from volcanic deposits in many parts of the world. Due to technical and economic factors, however, producers could not compete in price with sulphur from salt domes. •The result has been that, except in Japan and Chile, little sulphur was produced from volcanic deposits from about 1910 until the start of the Korean war in 1950. Shortly after the outbreak of the Korean war, an acute world sulphur shortage developed and prices skyrocketed in many countries up to several hundred dollars a ton. Interest in volcanic deposits was renewed and exploitation of many was undertaken. Few of these operations have been successful, mostly due to inability of management to solve technical problems.While important volcanic deposits of elemental sulphur have not been reported ( 1) in Canada, and it is doubtful that any will be found, data presented in this paper may be of interest to students of ore genesis.This paper is based on field examination of numerous deposits of the volcanic type in North and South America."

Jan 1, 1954

By Will Callupe Arzapalo

The success of the minimization of blast induced-damage at Barrick?s Pierina Mine in Peru is the result of an effective working relationship between Mine Operations and the Geotechnical Services Department. A detailed design criteria manual is used to match the blast plan to the site?s varying rock types and slope designs. The Geotechnical Services Department has further developed a comprehensive pre- and post-blast checklist that is critical to the drilling and blasting process as it pertains to wall stability. Wall control blasts are evaluated with quality assurance field checks, vibration monitoring and frequency control, video assisted performance quantification and post excavation face profiling. These detailed observations are compiled and summarized in a blast performance evaluation that is considered to be an ?Industry Best Practice?. The information and detail provided by each performance summary allows accurate blast analysis and effective design refinement.

May 1, 2006

By Harry Perry

By 1980, the free world's need for economic sources of energy is expected to double. As a result, there will be a tremendous potential for all energy sources working together to supply the demand. For coal to continue its dominant role as a low-cost energy source, means must be found for it to meet the challenge of nuclear power and to overcome obstacles placed on its use by air and water pollution regulations. As the more limited reserves of gas and oil diminish, economic ways are also required for converting coal to synthetic liquid and gaseous fuels, and to chemicals, thus resulting in optimum utility of the most abundant low-cost fuel resource. The means for accomplishing these ends can only come about by a vigorous research and development program. Successful efforts by industry and government working together, both in America and abroad, will assure the continued use of coal to meet the world's energy demands. This paper discusses the emerging patterns of energy sources throughout the world and the role that research and development on coal will play in supplying future energy requirements.

Jan 1, 1967

By S. Oppenheimer, P. Au, R. M. Kearsey, J. Tsang, E. McDevitt

A new superalloy, ATI 718Plus® Alloy (718Plus), has been developed to have a 55oC higher temperature capability over the traditionally used Alloy 718, while maintaining favourable processing characteristics and intrinsic raw material costs. The fatigue and dwell-fatigue behaviour of four microstructural variations of 718Plus are evaluated and compared to Waspaloy: 1) standard heat treated condition (HT1), 2) standard heat treated condition with thermal exposure at 732ºC (1350ºF) for 1000 hours (HT2), 3) fine grain condition with a modified d phase (HT3), and 4) fine grain overaged through modified heat treatment (HT4). The results show that the steady-state fatigue crack growth rates of each microstructural variation and both alloys are identical, with all of the 718Plus variations showing a clear advantage over Waspaloy in the fatigue crack threshold regime. Dwell-fatigue results show that Waspaloy has better resistance to crack propagation under dwell conditions; however, optimization of the precipitate phase shows vast improvement in the dwell-fatigue resistance of 718Plus.

Jan 1, 2010

By B. K. Gorain

"As mining has evolved over a century, so are the challenges associated with mining. Mining of complex ore bodies at greater depths is a major challenge requiring high capital and operating costs due to remote locations, high energy costs, water quality and complex environmental issues. In addition, the stakeholder expectations are growing along with challenges associated with highly complex mine permitting processes and changing demographics of mining jurisdictions. The dynamic metals market adds to these challenges impacting the long term development and sustainability of mining projects.These challenges are compelling mining companies to look at various innovations with an integrated approach focusing on meeting the needs of various stakeholders. Mining companies are slowly tapping into some successful concepts that have transformed other industries such as manufacturing, chemical, pharmaceuticals along with oil and gas.This paper provides an overview of various innovations and technology developments in mineral processing that have shaped the current mining industry. A glimpse of the present and future challenges in mining is also presented. An integrated approach to problem solving involving various stakeholders is gaining momentum and this has been reflected in this paper. Various developments that are being pursed in mineral processing focusing on a change in the existing mining paradigm are also presented in this paper.INTRODUCTIONAs mining is evolving, so are the challenges associated with mining. Some of the key challenges are complex ore bodies at greater depths, high capital and operating costs, water scarcity and quality issues, high energy costs, complex environmental issues including tailings management, worldwide constraints on resource availability, more and more elaborated regulations in emerging economies impacting the permitting processes, increasing stakeholder expectations, changing demographics of mining operations with ever-changing cultural or community expectations and the urgent need for a better assessment of project viability, this in very dynamic metals markets impacting the dynamics of mining projects development and sustainability."

Jan 1, 2016

By K. C. Grogan

"GeneralGIANT ORE is complex, with the gold values for the most part occurring in extremely close association with arsenopyrite, stibnite, jamesonite, and a wide group of antimonial minerals locally termed 'the grey minerals'. Pyrite is the most abundant of the sulphide minerals• and minor quantities of chalcopyrite, galena, and sphalerite also occur. Pyrrhotite has been found in some sections of the mine, but to date none of it has been nickeliferous. Native gold occurs in varying amounts throughout the ore bodies.In 1944, ore dressing investigations were commenced on diamond-drill core rejects and samples of surface outcrop ore. Results soon indicated that treatment to produce satisfactory recovery of the gold values would involve fine grinding to 80-85 per cent minus 200 mesh, recovery of free gold by jigs, followed by flotation, roasting of the flotation concentrate, and subsequent cyanidation of the calcine. Proceeding from this information, the flow-sheet was prepared, plant design worked out, equipment purchased, and construction of the treatment plant commenced in May, 1947.The crushing, grinding, and flotation units of the plant were rushed to completion and commenced operation on May 12th, l.948, at 225 tons of ore per day. This rate was maintained until January 27th, 1949, when the Allis-Chalmers roaster and cyanide plants were completed and commenced operation. During the period May 12th, 1948, to January 27th, 1949, gold recovered by amalgamation was the sole source of revenue. Flotation concentrate was stockpiled pending the completion of the Allis~Chalmers roaster and cyanide plants."

Jan 1, 1953

By Carol E. Jones

Outline ? Reclamation is a primary mitigation. ? Understand baseline environment and land use. ? Determine reclamation goals. ? Selecting reclamation technology. ? Determine technical risk. Reclamation ? Primary Mitigation ? Through land and water disturbance, mining can have significant local and regional environmental impacts. ? Impacts can also result from associated land use changes. ? Reclamation is a primary tool that the mining industry uses to manage its environmental impacts.

May 1, 2008