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By B. F. Osborne

"A new sensor cannot be considered in isolation from the process in which it is utilized. This paper, describing an on-stream particle size analyzer, therefore gives considerable emphasis to the slurry handling techniques employed to ensure that the instrument is presented with a representative sample. A new sampler is described, which continuously abstracts a small, representative sample from a closed pipeline containing a flowing slurry. This sample is then diluted, thoroughly mixed and pumped to a head tank, from where a continuous stream is fed at a constant rate to the size analyzer. Data are presented to show that particle size segregation is minimal throughout this sampling and sample preparation. A continuous particle size analyzer based on a separation principle is described, and the basic parameters of size distributions, and how they relate to this particular instrument, are considered. Typical results are given. An electronic system is presented which accepts the basic sensor outputs, and converts these to a particle size signal suitable for process control. Finally, the use of an inplant computer to process the sensor signals to obtain a particle size signal is briefly considered."

Jan 1, 1972

By C. H. Attwood

Introduction In presenting this paper on the water-power resources of the Province of Manitoba, it was considered that a brief resume of the power resources of Canada, of the power already developed, and its utilization in the industries 9f the country, would be of particular interest in showing the rapid progress that has already been made. Amongst Canada's national assets, water power occupies a foremost place because of the facilities it provides for the development of her other great natural resources. The rapid development of the mining, pulp and paper, and general manufacturing industries, and the concomitant growth in urbanization, with its numerous demands for domestic, commercial, and municipal service power, have combined to stimulate hydraulic development to a point surpassing even the most sanguine predictions of a few years ago. With the bringing into operation during 1928 of hydraulic turbines aggregating over 550,300 h.p., and of a further 378,400 h.p. in 1929, Canada's total hydraulic development at the end of 1929 amounted to over 5,700,000 h.p., and in this year, 1930, the active construction in hydro-electric plants throughout the country totals in excess of 1,600,000 h .p.

Jan 1, 1930

By Douglas A. Grieg

THE EXCUSE for producing still another paper dealing with the oilfields of the Middle East is the overwhelming importance of this area to everyone, both inside and out of the oil industry. Figure 1 shows the area defined as the Middle East for the purpose of this paper. No description of what constitutes the Middle East is generally acceptable to everyone and, in fact, in many parts of the world it is referred to as "Western Asia". At the time ?the writer went to work as a geologist in the Middle East -this was in 1926 -there were just three known oilfields, namely, Hurghada in Egypt, Naft Khaneh in the Transferred Territories of Iraq, and Masjid-i-Sulai-man in Persia. Their combined producing rate at that time was around 100,000 barrels per day. Toda y, just thirty years later, some forty-two fields have been proven to exist, and a recent discovery in Syria -if commercial -may add one more to the list. Producing rates at the end of last year ( 1956) were approaching four million barrels per day. This sizable figure re presents nearly 23 per cent of the total Free World's production. What is more important still, something over 70 per cent of the Free World's proven oil reserves are known to exist in the subsoil of the Middle East.

Jan 1, 1957

By D Maschemeyer

The cobalt production of the Chemical Metallurgical Division of Sherritt Gordon Mines Limited was supplemented, from May, 1962, to June, 1964, by processing 3,500 tons of a calcined cobalt-nickel concentrate. This paper describes the reduction roast -aqueous sulphuric acid leach process and the operating practices employed in recovering cobalt, nickel and copper from this oxidized by-product of a lead-copper operation. Incorporated in this paper is a description of how this process was integrated with the existing ammonia leach -hydrogen reduction process for the recovery of nickel and with the soluble cobaltic ammine process for the recovery of cobalt. Introduction T HE Chemical Metallurgical Division of Sherritt Gordon Mines Limited at Fort Saskatchewan, Alberta, has recently completed ten years of operation utilizing the ammonia leach process for the recovery of nickel, cobalt and copper from sulphide concentrates, matte and other materials amenable to this process. A continuing development program, along with the expansion of certain facilities, has enabled the refinery to attain a production rate of 31, 000,-000 pounds of nickel per year by hydrogen reduction. This represents an increase of approximately 85 per cent over the original design capacity of the plant.

Jan 1, 1965

By C. Edwards

ABSTRACT The versatility and specificity of rare earth elements (REEs) have led to their use in an everincreasing variety of applications in new technologies; consequently, demand for REEs has increased significantly. However, separating REEs safely and effectively is a complex and expensive process. This paper presents a review of REE mineral processing technologies, providing an update on current capabilities in REE mineral processing and REE extraction from the major commercially valuable REEbearing minerals such as bastnaesite, monazite, and xenotime, as well as the ion-absorption type of REE deposits.

Jan 1, 2013

By B. K. Choi, S. H. Kang, G. E. Kim, K. B. Kim, S. Noh, T. K. Kim, H. J. Jin

Oxide dispersion strengthened (ODS) steel is being considered as an in-core structural material of future nuclear reactor systems because of its excellent creep and irradiation resistance on the basis of uniformly distributed nano-oxide particles with a high density, which is extremely stable at high temperature in a ferritic/martensitic matrix. Up to now, ODS steels have been intensively studied and developed to apply these materials to the in-core structural component of future nuclear systems. The primary activity is to develop high strength advanced ODS steel, fabrication technology for the structural components and key joining technology for the component fabrication. As a result, a Fe-10Cr-1Mo alloy with a superior creep resistance at high temperatures has been developed. An optimized fabrication process of this alloy system has been established through various process conditions in mechanical alloying, hot/cold working, and heat treatment processes. Joining technology for the ODS steel components is also being developed using solid-state welding such as magnetic pulse welding, friction stir welding and diffusion boding. These R&D activities will contribute to the realization of ODS materials for future nuclear reactor system applications.

Jan 1, 2015

By J. Jerome MacDonald, Stephen B. Flewelling

"In the base metals industry of today, operations required to continuously improve productivity and reduce unit production costs. Consistent with these goals is the improvement of the muck haulage cycle from open stopes with the No. 12 Mine.Existing haulage from open stopes occurs with LHD units experience at Brunswick indicates that LHD units have a higher unit cost per tonne mucked than loader-truck combinations when the haulage exceeds approximately 150 m.The reintroduction of open stoping at Brunswick made existing loader-truck combinations unsuitable. It was recognized that application of recent continuous loading technology could potentially result in significant unit cost savings and productivity increases.A review of the technology resulted in the testing of the Voest Alpine AL60 loader in the open stopes located on the 1000m Le vel. Testing began in January 1988 and finished in late November 1988. The test will provide experience as well as quantified production and maintenenace parameters f or the purpose of quantifying production unit costs and system productivity, ultimately resulting in a decision to further utilize or not utilize the loader as a primarymucking unit at Brunswick .INTRODUCTIONBrunswick Mining and Smelting Corporation Ltd. produces approximately 10500 tonnes per day from the No. 12Mine located 35 km southwest of Bathurst, New Brunswick Mining is the largest (single mine) producer of zinc in the world having mined over 52 million tonnes since 1964. Many years of production still remain with proven and probable reserves in excess of 90 million tonnes. Reserves grade at an average of 3.65% Pb. 8.99070 Zn, 99g/mt Ag and 0.32% Cu . The operation employs 1446 people with approximately 800underground including operations and maintenance staff.In the No. 12 Mine two major mining methods are presently utilized . The primary method is Mechanized Cut and Fill (MCF) accounting for approximately 6500 tonnes per day from four major areas. The remaining 4000 tonnes per day is produced from open stopes with the majority of 2800 tonnes per day being produced by the 1000 level.The 1000Level contains 30 million tonnes segmented into open stope blocks 30 m high, 15m and 30 m on strike , with a transverse width of 10m to 50 m (Fig. I). Stopes are organized on a primary secondary stope arrangement along strike. Primary stopes are undercut and overcut full size with the back fully cablebolted. All stope and lateral development is driven 4.0 m high. All stopes to date are flat bottom (Fig. 2). Primary stopes are filled with cemented rock- fill , secondaries with conventional rockfill, Haulage from the stopes is primarily with 8-yard LHD units ; mucking is approximately 50% conventional and 50% remote. Haul distance to date has averaged approximately 150m with current stope haul distances of approximately 300m. Haulage is presently to a small jaw crusher situated on the 1000 Level. From August 1989on, haulage will be to a set of ore passes feeding to a large gyratory crusher situated on the 1200 Level. Start up of the gyratory crusher corresponds to an increase in tonnage from 1000 Level to 4100 tonnes per day."

Jan 1, 1989

The topic of the relationships between energy and particle size has had two very active periods -the first in the early thirties, when the relative merits of Rittinger's and Kick's proposals were vigorously debated; the second in the early fifties, when Bond's Third Theory was published. This second stage has produced several contributions that have provided a clearer picture of energy /size correlations in comminution. Derivations of a general relationship have been made from single-fracture experiments and from the rate of comminution, and both methods arrive at an equation of the type E = AK-11? The constant A in the equation may be regarded as a grindability parameter. In some respects, an understanding of the phenomena associated with comminution is still lacking, and research in this field should therefore be expanded. T HE SEARCH for a relationship between the energy consumed in comminution and the size of the broken product has been long and varied, and many

Jan 1, 1964

"THE Canadian Advisory Committee on Coal Research, which is commonly known as CACCR, has been in existence for the past five years and has held annual meetings during that period. This Committee is comprised of representatives from: the Mines Branch, Fuels and Mining Practice Division, Ottawa; the Geological Survey of Canada; the Dominion Coal Board; and the Provincial Research Councils and Foundations. It embraces all coal research in Canada that is sponsored, for the most part, by Government funds.To bring the country's coal research activities to the notice of the Canadian coal industry, the Coal Research Committee of the Coal Division, C.I.M., passed a resolution at the 1964 business meeting in favour of recommending the publication of an annual research report prepared by the CACCR. The first such report was published in the September, 1964, issue of the C.I.M. Bulletin; the second appeared in the November, 1965, issue of the same publication."

Jan 1, 1966

By P. J. Lunder, R. C. Pakalnis

This paper presents the results of research that has been undertaken in order to develop an improved method of determining the strength of hard-rock mine pillars. Pillars are found in various shapes and sizes in all underground mining operations. Prudent engineering design requires that if pillars are to perform as desired, both the pillar strength and the pillar stress must be determined. A detailed pillar stability study has been combined with an extensive database of published pillar case histories (178)resulting in a new “hybrid” pillar strength formula, “The Confinement Formula”, that utilizes classic strength of rock methods combined with empirical methods. “The Confinement Formula” utilizes a “mine pillar friction term” calculated from the average minor/major stress ratio with-in the pillar core. Statistically, the new formula provides better results at predicting pillar strength for the combined database than the best empirically ft pillar methods that currently exist. “The Confinement Formula” allows for the determination of the strength of mine pillars with an increased level of confidence over previously applied methods.

Jan 1, 1997

By Lloyd Buckingham

Barrick Gold Corporation (Barrick) has undertaken innovative methods of evaluating and improving the performance of grinding mills in several of its operations around the world. The results have been positive with some of the mines showing more than 20% net energy improvement leading to more than 43,000 tonnes per year reduction in CO2 emissions in four of the operations reviewed.

Jan 1, 2012

By A. Holland, T. Krumins, E. Olin, J. F. M. Castilleja, J. Geldart, C. Fleming, I. Jackman

A flowsheet has been developed to treat the flotation tailings from a copper mine in Mexico to recover gold and silver by cyanidation and carbon-in-pulp (CIP). The plant will treat ~15,000 t/day of a 60:40 blend of current flotation tailings and the mine’s historic tailings. The tailings also contain a significant amount of cyanide-soluble copper, and the economic viability of the project is strengthened by recovering most of the copper and cyanide associated with this process. The solution and solid phases in the CIP tailings will be separated in a counter current decantation (CCD) circuit and the CCD solution overflow will be treated by a SART Process. Copper precipitates as a salable copper sulphide product in the SART Process and the cyanide that is associated with the copper complex is regenerated as free cyanide. After SART, a portion of the SART product solution will be recycled to leach to reuse the free cyanide, while the remaining solution will be used as wash water in the CCD circuit. Incorporation of the SART Process in the flowsheet allows the CIP circuit to be operated aggressively as a gold plant, which means most of the silver in solution passes through CIP to SART. Silver co-precipitates with copper in SART and is recovered very efficiently with the copper sulphide by-product. Incorporation of SART also allows the leach and CIP circuits to be operated with relatively high levels of free cyanide, which enhances silver leach kinetics and helps keep copper from loading onto the carbon in CIP. The flowsheet was developed in the laboratory and successfully demonstrated in a fully-integrated pilot plant in 2018.

Jan 1, 2019

By Rodrigo Serna, Nora Schreithofer, Zoltan Javor, Kari Heiskanen

"Mineral floatability is a function of mineral properties such as size, liberation, shape, surface composition, reagent coverage on the surface, level of oxidation on the surface, etc.; pulp chemistry: Eh, pH, temperature, DO, reagent type, etc. and hydrodynamic conditions: turbulence, gas dispersion, D32, etc. The biggest challenge with predicting the floatability of an ore is finding a measurement method that would take into account the effect of all of the variables on the floatability of the minerals. The particle-bubble attachment time measurement is considered as an alternative way to predict the floatability of minerals instead of using expensive and time consuming flotation tests because it takes into considerations both surface chemistry and hydrodynamic parameters present in the froth flotation. The existing particle-bubble attachment time method is suitable for studying some significant flotation variables such as pH, temperature, particle size, reagent type and concentration. Nevertheless, measuring the attachment time as a function of collector coverage or surface oxidation is much more challenging. This paper introduces a new induction timer designed to measure the effect of galvanic interaction on the attachment time of particles. The new setup employs an array of needles to create 6 bubbles with the average size of 2.1 mm. Imaging system is used to set the initial distance between the particle bed and the array of bubbles. The attached particles are collected and sent for further analysis. One of the main benefits of the new experimental setup is that the attached particles can be physically separated from the unattached particles therefore many of the particle properties can be analysed and evaluated.INTRODUCTIONSchumann (1942), and Tomlinson and Fleming (1963) proposed that the flotation rate constant is dependent on four probabilities: particle-bubble collision (PC), particle-bubble attachment (PA), particlebubble aggregate stability in turbulent environment (PE), and particle-bubble aggregate stability in froth phase (PF). Any change in any of these probabilities will affect the overall flotation rate constant. All of the above-introduced probabilities are influenced by stream- variables and mechanical variables but their extent of influence vary. The stream variables are particle properties that have been shown to affect flotation rate constant such as size, shape, liberation, mineralogical composition, reagent surface coverage, surface oxidation, etc. The mechanical variables are the direct and indirect properties of the flotation unit affecting flotation rate constant such as cell and impeller geometry, air rate, impeller speed, air holdup, bubble size, residence time, hydrodynamics, froth depth, etc. For instance, the probability of collision is affected by many mechanical variables (bubble size, hydrodynamics, bubbles holdup etc.) but only one stream variable (particle size) has a major effect on it. On the other hand the probability of attachment is affected by much more stream variables: particle size, shape, liberation, surface composition, particle surface oxidation and collector coverage, Eh, pH, etc."

Jan 1, 2016

By J. R. Kadambi, J. Furlan, Kucukal E.

"Hydrocyclones are used in various industrial applications, including mineral processing and tailings management, to separate or classify solid particles and/or liquid droplets from multiphase feed. The fluid flow in a hydrocyclone (used in mineral processing) was investigated numerically and experimentally using particle-image velocimetry (PIV) and refractive index matching techniques. Two turbulence models were used in the calculations: the k–? model and the Reynolds stress model. Particle image velocimetry measurements were taken at various spatial locations along the cyclone. Computational results were validated globally using pressure and flow-rate readings at the boundaries, and locally by comparing the PIV velocity-vector maps and profiles.RÉSUMÉ On utilise les hydrocyclones dans diverses applications industrielles, dont la minéralurgie et la gestion des résidus, pour séparer les particules solides et/ou les gouttelettes liquides de l’alimentation polyphasée, ou pour les classifier. Une étude numérique et expérimentale sur l’écoulement des fluides dans un hydrocyclone (dont on se sert en minéralurgie) a été menée à l’aide des techniques de vélocimétrie par images de particules (PIV, de l’anglais particle image velocimetry) et d’appariement des indices de réfraction. Deux modèles de turbulence ont été utilisés dans ces calculs, à savoir le modèle de turbulence k–? et le modèle aux tensions de Reynolds (RSM, de l’anglais Reynolds stress model). La valeur de la PIV a été mesurée à diverses positions spatiales le long du cyclone. Les résultats de ces calculs ont été validés globalement à l’aide de relevés des pressions et du coefficient d’écoulement d’une extrémité à l’autre de l’hydrocyclone, et localement à des coordonnées spatiales spécifiques en comparant les cartes et les profils du vecteur vitesse PIV.INTRODUCTIONA hydrocyclone is a piece of equipment used to separate and/or classify solid particles or liquid droplets from liquid solid or liquid-liquid feed. Versatile in application, hydrocyclones have been widely used in industrial applications including the food, oil, power generation, chemical, and mineral processing industries. The first hydrocyclone was introduced in 1891 by Bretney to purify various liquids (Bretney, 1891). Hydrocyclones have a relatively simple design with no moving parts, which leads to an efficient separation process."

Jan 1, 2017

By L G. White

During 1958, prospecting parties working for the Mackenzie Syndicate in the Flat River area of the Mackenzie mountains, Northwest Territories, identified tungsten mineralization and located the property now being developed by the Canada Tungsten Mining Corporation Ltd. Scheelite mineralization, associated with pyrrhotite and minor chalcopyrite, occurs in lime silicate skarn replacement zones within a limestone-chert-argillite series intruded by granitic dykes originating from the ? main batholithic mass underlying the sedimentary beds. The results of surface outcrop sampling and 15,000 feet of grid-pattern diamond drilling have been combined to outline an orebody estimated to contain 1.32 million tons, grading 2.51 per cent WO after applying a 10 per cent dilution factor for mining purposes. T HE property of Canada Tungsten Mining Corporation Ltd. is located in the upper Flat River area of the Mackenzie mountains, Northwest Territories. Skarn-type replacement deposits containing scheelite mineralization are .situated between elevations of 4,500 and 5,500 feet above sea level along the east flank of the mountain range forming the boundary between the Yukon Territory and the Northwest Territories. The nearest supply center for the area is Watson Lake, Yukon Territory, located at Milepost 635 on the Alaska Highway.

Jan 1, 1963

By B. W. Clyburn

"Coals from the Corporation's Lingan and No. 26 mines are classified as high-volatile A bituminous, with a very low inherent ash and containing all essential properties to provide metallurgical coal, with the exception of a high sulphur content. Only through proper cleaning at low specific gravity can the pyritic sulphur fraction of the coal be liberated to an extent where final sulphur meets coking standards. This first section of the paper deals with the operation of a Dutch State Mines heavy-media cyclone circuit to achieve an actual separation in the region of 1.30 specific gravity. A discussion of the parameter of control which must be applied along with an appraisal of the results obtained is included in the paper.Introduction Very high fluidity and unusually low ash are the outstanding characteristics of coal from Devco's mines in the Harbour seam of the Sydney coal field. However, sulphur content, mainly pyritic, ranges from 1 to 2.50Jo. To obtain the low and consistent sulphur level required in metallurgical coking coals, preparation at low specific gravity is required. Metallurgical coke is used as the fuel in an iron blast furnace. Its sulphur content largely determines the quantity of slag required to remove it and therefore influences furnace productivity and unit costs. Typical data on the various coal properties of importance in the production of coke are included in Table 1."

Jan 1, 1985

By J. E. Nesset, F. Rosenblum, J. A. Finch, R. Payant

ABSTRACT Under certain conditions of moisture and oxygen, sulphides can spontaneously self-heat. We tested a hypothesis that galvanic interaction between some sulphides can promote self-heating. Galvanic interaction is controlled by the rest potential difference between sulphides and particle size. A series of binary sulphide mixtures was tested. Individual sulphides and mixtures with low rest potential difference did not self-heat, but mixtures of high rest potential difference did. When testing pyrite-sphalerite mixtures, self-heating increased inversely with particle size, with the fineness of the pyrite governing self-heating, indicating the rate-limiting step is the reduction reaction. The results support the hypothesis that galvanic interaction contributes to sulphide self-heating. A possible mechanism based on hydrogen sulphide as an intermediate product is proposed. The understanding gained will be of interest to those involved in storage, shipping, and disposal of sulphides.

Jan 1, 2012

By J. -P. Lempainen, K. Haavanlammi, K. Valkama

The Outotec nickel matte chloride leaching process is especially suitable for small capacity standalone nickel refineries. The matte is leached with hydrochloric acid and oxygen in multiple steps in atmospheric OKTOP® reactors. Oxygen feed prevents reductive conditions and hydrogen formation in the leaching process. A sufficiently high acid concentration keeps the iron dissolved in the solution. The iron is removed after leaching by precipitation and the pregnant leach solution continues to metals recovery. The metals recovery from the chloride solution is done by solvent extractions, where ammonia is used for pH control. Copper and nickel are stripped from the organic phases into sulphate solutions. Metals can be recovered from the purified solution by conventional electrowinning. Other alternatives are precipitation or hydrogen reduction processes. The ammonium chloride in the solvent extraction raffinate is regenerated into ammonia. The calcium chloride solution from ammonia regeneration is routed to acid regeneration where sulphuric acid is added and ultra-pure gypsum is precipitated. The hydrochloric acid solution from this step is recycled back to leaching. The process yields good overall metal recoveries and expensive

Jan 1, 2014

By Fei Dai

Musculoskeletal disorders (MSDs) are a group of painful disorders that affect muscles, tendons, nerves, joints, cartilage, and ligaments. They are a serious problem among the workforce in the United States. In the construction industry, high physically demanding tasks expose construction workers to a number of well recognized MSDs risk factors such as repetitive motion, high force exertion, and awkward body posture. Finding ways to effectively identify and evaluate risks of MSDs can significantly alleviate this problem. To this end, this paper reviews state of practice and research in the assessment of risks of MSDs among construction workers, in which a number of biomechanical models have been developed to evaluate joint and tissue loading with the aid of state-of-the-art remote sensing technologies. Findings from the review reveal that despite the advances in tracking human motion and muscle activities, current remote sensing approaches still involve sophisticated instrumentation and expensive experiment setup. These factors greatly limited the applicability of such approaches in real construction settings. How can we detect and evaluate the construction worker?s MSDs risk in real work environments? In this paper, strategies by utilizing video surveillance systems are presented, to set the stage for addressing the above question and discussing future research in real-time, marker-less, and costeffective MSDs risk assessment.

Aug 1, 2013

By F. T. Mooney

Introduction The Flin Flon mine of the Hudson Bay Mining and Smelting Company, Limited, is on the interprovincial boundary between Manitoba and Saskatchewan, about four hundred miles north of the Canada-United States boundary. The orebodies are gold, silver, zinc, and copper replacement deposits occurring as irregular lenses of massive sulphides, arranged en echelon, and irregular masses of disseminated copper sulphides in chlorite. The country rocks are of Precambrian age, dominantly lava flows. Development of the Mine The mine is opened by two vertical main shafts- the North Main and South Main shafts- 3,800 feet apart. The North Main shaft has a depth of 2,210 feet and the South Main shaft is completed for stoping operations to the 3,250-foot level (see Figure 1). These shafts are connected by main haulages driven, on the footwall side of the orebodies, at 520-foot intervals down to the 2,210-foot level. No. 3 (subsidiary) shaft is on the footwall side of the orebodies at a point between the North Main and South Main shafts, 2,400 feet south of the former. It has a depth of 3,250 feet and connects with all main haulage levels- with both Main shafts down to the 2,210-foot level and with the South Main shaft on the 2,750-, 3,000-, and 3,250-foot levels. Other openings tO the mine include B North fan raise, the opening due to the recovery of the open pit sill pillar, and several back-fill raises.

Jan 1, 1949