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By G. G. Eichholz

SUMMARY RADIOACTIVE dynamite has been prepared by introducing a small amount of antimony-124 into the explosive. Test work is described on the effectiveness of this tracer, on radiation levels in its neighbourhood, and on different methods of .application. Factors determining the choice of isotope, amount of activity, and overall cost of this process are discussed. INTRODUCTION Instances are known in which dynamite remains unexploded in drill holes in mining operations. Usually such 'bootlegs' are easily located by inspection of the face and the powder is removed before subsequent drilling is started. Occasionally, however, serious accidents occur because workmen drill into an undetected piece of dynamite. In order to avoid such accidents it was suggested that a different method of location might be tied, such as that afforded by the use of radioactive tracers. This paper describes some experiments that were carried out under the auspices of the Department of Mines and Technical Surveys, with the active co-operation of Canadian Industries Ltd. and Canadian Refractories Ltd., to test the feasibility of such a scheme.

Jan 1, 1957

By E. J. Wasp, T. L. Thompson, T. C. Aude

The paper will deal with some of the more important technical aspects of slurry pipelines as they apply to the mineral field. In addition, the use of these technical concepts in arriving at realistic economic figures will be discussed.

Jan 1, 1970

By J. Baz-Dresch

"The most cost-effective method of placement of the high strength fill used in the Cannon Mine' s overhand cut-and-f ill bench stopes was determined to be truck haulage. Constraint s imposed by the mine layout dictated the use of a truck which could dump its load in a fifteen-foot high drift. The Dux Teledumper truck was selected as the most suitable unit for this application based upon operational and maintenance parameters which included a telescoping, tilting dump box; large load capacity; and robust construction. Development of the truck continues through the cooperation between the manufacturer and user. INTRODUCTIONThe Cannon Mine is situated in the centre of Washington state, approximately midway between the cities of Spokane on the east and Seattle on the west. The mine complex is located three block s south of the Wenatchee city limits at the eastern base of the Cascade Mountain range.Asam era Minerals (U.S.) Inc., with 5I% ownership, operates the Cannon Mine. Breakwater Resources, Ltd. holds the remaining 49%.Annual paroduction is 520 000 tons per year, presently on a 21-shift per week operating schedule for both the mine and the mill.All production is presently won by overhand bench stoping with backfill. Stoping starts with 15-ft high by 24- or 30-ft wide sill cuts driven above and below a stope block . A drop rai se and slot are used to open a bench which is then slabbed toward the open slot. Truck-placed backfill is dumped into the mined - out stope from the upper sill cut. This stoping sequence is repeated until the top of the ore block is reached . The top sill cut is then tightly filled with backfill to minimize subsidence and to provide adequate roof support during extraction of the pillars.Mining equipment consists of hydraulic drills and rubber-tired, diesel scoops and trucks."

Jan 1, 1989

By Matthew Scott

Introduction The refining of precipitate is the final stage of all the processes involved in gold mining and cyanide milling, by which the precious metal is at last obtained in a concentrated form, which can be accurately valued and marketed. Possibly one ought to say, conveniently shipped, for accuracy in valuation depends in many instances on a toughening treatment given the bars as received at the Mint so as to obtain a homogeneous metal that lends itself to representative sampling; which, of course, entails a surcharge on the regular Mint charges for the extra work necessarily undertaken. There are several methods of refining zinc-gold precipitate, each with its advocates; the method employed depending not always on the quality of the bullion produced but on the local exigencies of the case in point. These methods are more or less detailed in various textbooks and it is not the purpose of this paper to discuss them, but to confine ourselves to the specific case as stated in the title of the paper. At the outset, it behooves the writer to express his thanks to Mr. Brigham, the General Manager of the Hollinger Mines, for the kindly consideration and encouragement given in developing this process. This will be better understood when one considers the immense values involved, tending towards conservatism in practice, and making one chary of radical innovations. This process has been in satisfactory operation now for about two and-a half years, during which time over twenty-five million dollars value in fine gold has been produced, so that it may be reasonably held that the process is successful.

Jan 1, 1931

By G. Wilson

"Satisfactory hydraulic performance of a centrifugal slurry pump is not the only design criterion. If abrasive wear exists the severity of any damage can be reduced and the life of the wearing parts prolonged by selecting the correct pump to suit the conditions of service. This paper is concerned with the design and construction of centrifugal pumps for handling abrasive solids. The wear phenomena due to the slurry being pumped and the materials used to combat abrasive, wear are outlined. The hydraulic design of the impeller and casing and their relationship to wear and the hydraulic radial and axial unbalance are discussed. The prediction of abrasive wear in pumps can not be precise, as many factors are involved - and this is the object of current research."

Jan 1, 1973

By Thomas R. Larson

"Many concentrators use re-circulating “plant” water for dilution in their flotation circuits. However, if crusher dust suppressants, ball mill grinding aids, or even agitator bearing grease are introduced into this water, and the water itself is not subject to cleaning steps, then sufficient quantities of these chemicals may appear in the flotation cells and begin to impact the flotation separation. A bench flotation procedure has been coupled with statistical analysis in order to estimate the impact of small quantities of non-flotation chemicals on flotation performance.INTRODUCTIONCleveland Cliffs produces iron oxide pellets for blast furnace feed, and is developing the capability to produce ferrous metallic products to supply a wider customer base. Cliffs manages five North American iron mines, including the Wabush mine sites in Labrador and Quebec. Based on various characteristics of the ore bodies, the flow sheets of the five mines are diverse. For example, Hibbing Taconite uses magnetic separation alone as their primary upgrading method, but Northshore and Empire use magnetic separation followed by flotation, and Tilden uses flotation alone. Last but not least, the Wabush concentrator upgrades primarily with gravity and electrostatic separation techniques.At Northshore, concentrate from the magnetic separator circuit is fed to a reverse flotation circuit. By design, the magnetic separators operate at the highest possible recovery of magnetite, as the separator tails are discarded, and relatively high silica content was acceptable to Northshore’s customers. As the steel-making industry moved toward lower and lower slag volumes, the silica content in the magnetic separator concentrate became a problem. The flotation step was added in the late 1980s in order to decrease the silica assay of the magnetic separator concentrate to meet the current customer requirements. In this setting, the flotation feed stream contains very little silica that occurs as liberated quartz particles. As the degree of liberation of the flotation feed stream is then a limiting factor for silica removal, the online grind control then was linked to flotation in the overall plant control system so that grind can be adjusted to achieve improved liberation if necessary for the flotation process."

Jan 1, 2002

By Joanna LaForte

"IntroductionIn respect to The Human Dimension by M. Phyllis Bray, this author's impression is that research on long distance commuting (LDC) is long overdue. This type of mining is not new to many workers, especially those from areas such as the Maritimes, who have had to look for work away from their families for at least a decade. Perhaps to the industry the over-all set-up is new, but to workers who have faced mine shut-downs in their areas finding a job was the main objective and if the security of long-term employment was evident, then the families might join them later. This was the situation with which the writer' s family was faced.LDC LifestyleBeing the wife of an underground miner, the author has personally experienced this lifestyle for almost 10 years, and has never experienced accommodation in a company town. The first five years of marriage were spent in a small rural municipality within 50 miles of the worksite, but the town had industry separate from mining and was not affected by the mine shut-down.Since her LDC lifestyle began her family has been pretty much city-based, out-of-province commuters with two children and a third to arrive some years later. She therefore lived a fairly normal married life with a husband home daily. The author has experienced life with a husband who worked away for five-day stretches and then drove long distances to be home weekends or the portion of time left over from driving and fatigue. She has done the 3D-days in/l4-days out routine, and for approximately the past four years has been existing on a two-weeks in/two-weeks out ritual .The author does not agree that the ""bottom line is that mining families go where the jobs are"" . The miners go where the jobs are and the families fend for themselves with the assistance of the pay cheque making it home each pay period.Perhaps because there are many personal frustrations with this type of lifestyle, perceptions may be inaccurate. Having only dealt with underground operations, there may be gross differences between the pressures and demands of other forms of mining."

Jan 1, 1991

Over the last three decades, the mining industry has been moving towards more underground mechanized mining methods and the number of LHD vehicles utilised has increased. The growth of mechanization and automation has benefited both workers and the mining companies. However, due to the design of the LHD vehicle and the limitations of the operating environment, restrictions to operator visibility are inevitable. The inability of the equipment operator to see clearly (i.e. people, objects or hazards) around the machine has contributed to a number of accidents including fatal injuries. In order to identify vehicle design characteristics resulting in restricted and blocked sightlines, visibility assessments for existing machines are traditionally completed in the field using a light filament technique. Past researchers have used the light filament technique to collect obscuration zones around the equipment and to produce a 2D chart of this information. The 2D shadow diagrams have proved to be useful in highlighting potential equipment problems and have been performed repeatedly to show the potential of redesigning a part of the LHD for improving visibility. The light filament method involves manually collecting data and requires a level of judgment to be used. As a result the method is susceptible to errors and requires around three hours to complete. The objective of the current research is twofold; firstly to develop a rapid method for field visibility data collection using a laser scanner and secondly to compare results of repeat tests for both light filament and laser scanning methods. A MENSI GS100 laser scanner along with Pointscape and 3Dipsos software has been used to collect visibility information and process the data. The research aims to develop the laser scanner as a technique to rapidly evaluate the visibility profile of an LHD vehicle. Machine design changes can then be assessed quickly using these results.

May 1, 2004

By W. E. Oching, M. M. Ghomshei

"Collaboration among Ventilation Engineers, Mine Inspectors, worker representatives, health and safety officers and management is key to an effective operational mine ventilation management. Mine ventilation training, ventilation survey reports for mine stakeholders and interaction with mine frontline workers and management concerning safety, energy saving, assets management and maintenance are effective tools in implementing best industry practices and significant reduction of ventilation operating costs without compromising safety. These approaches may not be new to well established mining companies but the real dilemma is how to implement them effectively and this is what this paper will address.INTRODUCTIONManaging an effective mine ventilation system is becoming increasingly challenging, especially during tough economic times in the mining industry. Management strives for more production while frontline miners work hard to surpass the production targets, thus improving their incentives and above all aiming to enhance the prospects of their job security when the mining industry is facing challenging times. Taking shortcuts by not fully following the safety regulations or industry best practices are often notable, resulting in the rise of Workers Compensation Board claims and temporary shutdowns of active workings, compromising productivity and increasing the operating costs.In accordance with the Mines regulations in various jurisdictions in Canada and the US, it is evident that companies adhere to establishing basic ventilation management systems through the provision of the code of practice, procedures, work practices and standards/guidelines. This is aimed at ensuring the health and safety of underground workers (de Souza, 2017). However, the challenge to many operations is the improper implementation of the mine ventilation regulations including some managers showing reckless disregard for workers safety by focusing on production and not worrying to address ventilation problems (Steven & O'Keefe, 2010). Other challenges facing effective ventilation management include inadequate training of frontline workers on ventilation system and hazards associated with poor ventilation systems such as toxic gases, dust, heat, and underground explosions (Mufson et al., 2010; Suvar et al., 2017); friction between mine managers and the mine inspectors (Mufson et al., 2010), improper maintenance of ventilation system and inventory management, among others."

Jan 1, 2019

By Henry Lepp

Introduction A shaft sinking operation carried out at the Viking Yellowknife mine in the spring of 1947 presents certain features, especially as regards speed of sinking and low cost, that may be of interest to Institute members, and especially to those who are not familiar with conditions and costs in the Northwest Territories. After collaring, the inclined, two-compartment shaft was sunk 130 feet by four miners in twenty-eight days at a direct cost of only $53.19 per foot. All things considered, this is a remarkable performance, even if it does not actually establish a record. The property is at Morris lake, some forty-five miles north of Yellowknife. Formerly owned by Athona Mines (1937), Limited, it was acquired by the then newly incorporated Viking Yellowknife Gold Mines, Limited, in 1947. Surface work and diamond drilling in 1946 disclosed a number of veins and masses of quartz in a sill of diorite which lies conformably within sedimentary rocks. The sill strikes N.30°E. and dips at 70° to 85° southeast, and has a mean width of 40 feet over its explored length of 3,000 feet . Both the quartz and the diorite carry gold and are mineralized with pyrrhotite and lesser amounts of galena, sphalerite, chalcopyrite, and arsenopyrite. Of thirty-five holes drilled in the mineralized zone, the core from twenty showed visible gold. Sampling of drill cores indicated several ore shoots in the north and central parts of the sill. Assays, however, were somewhat erratic, possibly due to the fairly widespread presence of visible gold, and it was decided that the deposit could best be explored by underground sampling. Accordingly, late in 1946, plans were laid for the sinking of a shaft.

Jan 1, 1948

By Anthony T. Eyton

Intelligent Systems: Advantages for Mining ? Increased safety (reduced risk to workers) ? Increased productivity (reduced downtime) ? Reduced maintenance costs ? Customized solutions for different mines ? Growing acceptance among mine managers A Typical Precarn Project ? Meets definition of intelligent systems ? Involves at least two Precarn members ? a technology developer partner and a user partner ? in a true collaboration ? Involves at least one university and may have various other players ? Leads to a demonstrated prototype ? Costs $2-4 million, and lasts 12-30 months ? Gets up to 40% of its funding from Precarn (max. $1 m) ? Produces new intellectual property -- owned by the project team

May 1, 2002

By J. P. Dick

THIS paper is a description of the milling practice and metallurgy at the Moneta Porcupine mine, Timmins, Ontario. The results obtained with an all-cyanide circuit and later with flotation followed by cyanidation are described. The ?investigation which prompted the various changes in milling practice have also been dealt with. Moneta ore is possibly the most refractory now being milled in the Porcupine district. This is due to the ultra fine state in which the gold occurs and to its intimate association with pyrite. No doubt there is ore of similar characteristics on the neighbouring properties but it probably forms only a small portion of the tonnage being mined, whereas at Moneta the bulk of the ore requires an extremely fine grind to liberate the gold. The fineness to which an ore can be ground economically has gone far beyond what was thought to be the limit only a few years ago. Formerly, a set of standard screens was all that was required to measure the fineness to which an ore was ground. At present, the Haultain infrasizer is practically indispensable, and the nominal micron has become a familiar unit of measurement to all those dealing with the problems of fine grinding.

Jan 1, 1941

By C. Liu

Corrosion behavior of the stir zone in a friction stir weld of dissimilar A12024/AZ31 alloys was investigated in the immersion test in distilled water (pH=6) for different times. Microstructures and the distribution of chemical elements were analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Due to the difference in the corrosion potentials between A12024 and AZ31, the AZ31 alloy constituent in the stir zone was susceptible to the corrosion attack in the distilled water. The corrosion attack was found to occur in the narrow region of the AZ31 alloy adjoining the A12024 region, where there was a low ratio of anode-to-cathode surface area. The corrosion attack became more severe in the AZ31 alloy regions with increasing immersion time. The A12024 alloy region in the stir zone of the weld was protected by cathodic reactivity due to sacrificial anode AZ31 alloy.

Jan 1, 2007

By P. J. Dunlop

THE object of this paper is to present a brief survey of the work done and the results obtained in controlling dust at the Hollinger Consolidated Gold Mines milling plant. The plant includes all primary and secondary crushing, grinding, and treatment operations. The major items of equipment are: (1) Underground Crusher Plant 1 48 in. by 60 in. jaw crusher, crushing run-of-mine ore to minus-6-in. Rate: 420 tons per hour (2) Surface Crusher Plant 3 No. 772 gyratory crushers 3 4 ft. by 16 ft. trommel screens 4 No. S gyratory crushers Reducing ore to rninus-172-in. Rate: 420 tons per hour (3) Roll Plant 5 sets of 62 in. bJ: 24 in. rolls 7 5 ft. by 10 ft. v1bratrng screens Delivering a minus-3/16-in. finished product Rate: 420 tons per hour (4) Grinding Plant 4 7 ft. by 15 ft. low discharge grate ball-mills 4 12 ft. reciprocating rake classifiers Rate: 4,800 tons per 24 hours Maximum capacity: S,800 tons per 24 hours

Jan 1, 1939

By P. Turcotte, E. Karampinos

"Construction of underground excavations in squeezing ground conditions faces several technical challenges that can result in delays in production and high costs due to rehabilitation. A review of the behaviour of drifts under squeezing ground conditions was undertaken at the LaRonde mine. In particular it focused on implemented strategies to control the observed large deformations. The mine experiences a large range of squeezing ground conditions, mostly driven by the presence of foliation and high stresses. This results in large deformations over one meter in radius. A comprehensive ground control strategy has been implemented with the aim to manage, rather than arresting drift closure. The evolution and effectiveness of the employed support strategy are discussed based on documented field observations. In complement to the field implementation numerical models are used to provide further insight on the observed squeezing conditions.INTRODUCTIONThe development of underground excavations under squeezing ground conditions is usually associated with excessive rehabilitation and significant failure of ground support due to large deformations. Cost research case studies have concentrated on squeezing ground conditions in tunnelling. An overview of the methods used for the identification and quantification of squeezing and the numerical methods for the simulation of these conditions in tunnelling has been provided by Barla (2002). Numerous support systems that can manage ground deformation are available for civil engineering tunnelling. Nevertheless, the use of these systems in mining would result in high support cost and production delays. Mining operations have higher development rates and shorter service life. This study focuses on the behaviour of underground excavations under squeezing ground conditions in hard rock mining.In a mining context, the magnitude of deformation is usually higher than in civil engineering tunnelling as there is a higher tolerance for operation purposes. Potvin and Hadjigeorgiou (2008) noted that in mining, squeezing is encountered when the total displacement of an excavation reaches at least tens of centimeters over the life expectancy of a supported drive and is associated with considerable damage to the ground support."

Jan 1, 2015

By K. Esmaieli

This paper addresses issues associated with ore pass degradation caused by material impact. A series of numerical experiments, using the particle flow code, were undertaken to investigate the influence of various finger raise configuration. This has allowed the identification of favorable configurations. The results of this analysis, when coupled with field observations, can contribute to the design of ore pass systems that can prolong the useful operating life of ore pass systems.

May 1, 2009

By J. Álvarez, J. Mesías, C. O. Gómez

"Operations routinely run flotation tests in laboratory mechanical cells to determine adjustments to plant operation based on feed flotation response or the effect of new reagents and dosages. The metallurgical results of these tests are certainly affected by changes in bubble size, which simultaneously impact the recoveries of the collection and froth zones. It is known that bubble size depends on the characteristics and operation of the machine in use, particularly on the gas flow rate delivered to the unit and the selected frother type and dosage. Although flotation rate constants have been related to bubble size, bubble surface area flux seems to be a more fitting variable to correlate flotation kinetics and cell performance, as it integrates bubble size and superficial gas velocity effects. However, although some evidence has been provided, a categorical relationship between cell recovery and bubble surface area flux has not been established. Our interest is to demonstrate this relationship to use it as a basis for developing soft sensors to track on-line collection zone recovery in cells. Flotation tests were designed to produce Cu concentrates for a range of bubble surface area flux values, obtained through changes in frother concentration at a constant gas flow rate, and by increasing gas flow rate at the same frother concentration. The tests were run on samples prepared from an ore batch supplied by a local operation, following strict grinding and flotation procedures, with a shallow froth to approximate cell recovery to that in the collection zone. Bubble sizes were determined using the sampling-for-imaging technique developed at McGill. The results unequivocally showed a consistent positive correlation between cell recovery and bubble surface area flux, and significant variations in performance when frother addition and gas flow rate were changed.INTRODUCTIONMineral flotation is a separation process to produce concentrates of valuable minerals by selective attachment of particles to the surface of bubbles. The process is carried out in machines where air is injected through a mineral pulp to form bubbles, and operated to create two zones: a bottom one (collection zone) where bubbles are continuously generated under conditions adequate to form bubble-particle aggregates by collision of the rising bubbles with suspended particles; and a top one (froth zone) where bubbles and bubble-particle aggregates continue to rise while concentrating and forming a froth layer for water and entrained particles to drain back to the collection zone, before overflowing as a concentrate stream. The phenomena occurring in these zones are complex and, in many cases, interactive, as they simultaneously affect stages of the particle separation sequence occurring in both zones. Although there have been significant advances in instrumentation to characterize particle and bubble populations, these have not resulted in knowledge to explain or models to describe phenomena from fundamental principles. Measurements continue to be limited to the development of empirical models for predicting the effect of operating variables on performance."

Jan 1, 2016

By C. G. McLaughlan

The Noranda concentrator was placed in operation in October, 1928, and the object of this paper is to outline operations during the twelve months which have elapsed since that time. The ores milled are massive sulphides carrying copper and gold, and, in certain cases, zinc. These ores have a specific gravity of about 3.8. The average assay of the copper-gold ore so far treated has been 2.0 - 3.5 percent Cu; 0.10 - 0.20 oz. Au; 40 - 51 percent Fe; and 6 - 15 percent SiO2. In this ore the copper occurs almost entirely as chalcopyrite, and the iron which is not combined with the copper is present mainly as pyrite and pyrrhotite. ?some iron is also combined with the silica, the ratio being about 1 to 4, and a small percentage is present as magnetite. The occurrence of the gold has been shown by microscopic work carried out by Prof. L. C. Graton, of Harvard University, to be very variable. Some of it is free, and is included within the base-metal sulphides or occurs at their boundaries. A similar distribution also holds for a portion of the gold which is combined as a telluride. Little is so far known of the occurrence of the silver other than that some of it may be combined with the gold in the telluride, petzite. The copper-zinc ore contains up to 6 percent copper, and has a very variable zinc content. The copper in such ore is present as chalcopyrite, and the zinc as sphalerite. In starting the mill we had three conditions to face; the first of these was climatic, the second was the lack of skilled flotation operators, and the third was the ore itself." The last of these three proved much more difficult to contend with than the other two combined.

Jan 1, 1930

By R. F. Coulter

THE Flin Flon concentrating and metallurgical plants (Figure 1) of the Hudson Bay Mining and Smelting Co., Limited, lie adjacent to the town of Flin Flon, on the Manitoba-Saskatchewan border, 400 miles northwest of Winnipeg. Since the start of milling operations in 1930, over 50 million tons of ore from the Flin Flon mine have been treated in the concentrator. During the past few years, newly discovered orebodies have been brought into production and their ores processed at the company's main metallurgical plants. All these properties are within a 75-mile radius of Flin Flon and have aided substantially in augmenting plant metal production as well as retarding depletion of ore reserves in the Flin Flon mine. •Current satellite producers are the Schist Lake, Coronation, and Chisel Lake mines. The Schist Lake mine, located 3 ½ miles southeast of the main plant, is a copper-zinc producer. It was brought into production in 1954. The

Jan 1, 1962

By The Hollinger Mill Staff

MR. E. L. Longmore (l), in presenting this paper at the Annual General Meeting, suggested that it was neither desirable nor necessary to read any but the briefest portion of the paper. He wished to emphasize that the scale of the milling operations at the Hollinger not only provided several units in continuous operation to ensure that the test work was being carried on under normal conditions, but also provided a large and competent staff to supervise such an extensive experiment and to criticize intelligently the recorded results. He wished to acknowledge the enthusiastic co-operation of the group of assistants whose excellent work was responsible for the confidence with which the conclusions could be presented. The following data were given as a supplement to the published paper. Following conclusion of the test work described in the paper, the size of the balls fed to the mill was changed from 3-in. diameter to 2Yz-in. Within a short time, a gradual rise in the tonnage rate took place and, as no other condition had been changed, the increased tonnage was credited to the changed character of the ball load. At present, the average daily tonnage for the mill with low discharge is 1,507 tons, an increase of 77 tons over the 1,430 tons ground when feeding a 3-in. ball. A similar increase in tonnage should be credited to the high-discharge test, if the 2;Y2-in. ball had been used at that time. This would raise the 1,117 tons ground at that time to a new figure of 1,177 tons. From a study made to determine those factors influencing the rate of pulp flow through the low-discharge mill, it became evident that the ball screen used on the high-discharge mill must have been restricting the flow through the mill, although this was not recognized at the time. Accord-ingly, it was decided to repeat the high-discharge run. Additional length was added to the 21-in. ring grizzly originally used, and the length of the reverse spiral was increased. The end of the grizzly was left open so that, if necessary, excess pulp might flow out. A coarse mesh 3 ft. by 3 ft. flat screen was provided to catch stray balls.

Jan 1, 1937