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By R. Minto, W. G. Davenport

The slag removed from the reverberatory furnaces of copper smelters contains significant copper values. A serious financial loss is involved, as further recovery operations are not normally carried out. This paper describes the factors affecting physical transport of matte into slag by gas bubbles, and the subsequent entrapment and flotation of matte drops. Three distinct patterns of transport behaviour have been identified from studies of a number of liquid/liquid systems, including liquid metal and liquid matte systems. A theoretical approach is proposed to explain these behaviour patterns, and to predict transport and entrapment behaviour in matte/slag systems. The concepts of "Film Coefficient" (ø) and "Flotation Coefficient" (?) are introduced. The effects of smelting process variables on the physical loss of copper matte in slag are also discussed.

Jan 1, 1972

By W. M. Goodwin

"IntroductionIN THE preceding paper we have learned about Canada's resources of metallurgical coal. There is an adequate amount in Nova Scotia, a very large reserve on the eastern flank of the Rocky mountains, and a strictly limited supply on the Pacific coast. Added to these is an unknown quantity of coking coal in the Peace River district, at present rather isolated but possibly capable of industrial development in the future.The chief use of metallurgical coal is to make iron and steel. For this, an adequate supply of iron ore is required. So we should now scan the Canadian supply of iron ore, the possibility of its increasing use at home, and the probable markets abroad.Trade in iron ore tends to be international, as is the case with many other raw materials. The present tendency with iron and steel, in contrast, is to keep its manufacture within national boundaries, and there is no evidence that this will change much in the years to come. We should keep these two points clearly in mind when considering the disposal of iron ore from Canadian mines. We should remember, also, that the modern blast furnace and steel plant has such a large output that a correspondingly large population, reasonably compact, is needed to consume its products.Large Ore Supply in East, Small in WestCanada has now four major iron ore fields, well situated to serve adequately the eastern half of the country. Wabana .and Labrador are well placed to serve overseas markets and plants on the eastern seaboard and eastern interior of the United States and Canada."

Jan 1, 1952

By O. D. Maurice

"This paper will essentially update the information that is already known and published on the limestones of the Province of Quebec. The excellent report by M. F. Goudge (1935)m is difficult to improve upon and the areas of limestone quarrying are generally the same as they were at the time of Goudge's report. Our knowledge of the limestones of Quebec has been improved considerably in recent years by the publications of T. H. Clark, 2 who, since 1938, has been mapping and reporting on these lime-stones and has discussed their stratigraphy, their structural features, their history and their economic value. One economic aspect is the presence of natural gas in these formations and the possible occurrence of oil. A total of 150 test holes had been drilled to a depth of more than 500 feet by the end of 1967 and, in addition, at least 256 more shallow holes had been put down in the St. Lawrence Lowlands. The information from these test holes has greatly improved our knowledge of the thickness and extent. of the various formations of Paleozoic limestone and shale in Quebec.This paper will then review briefly the limestone occurrences in Quebec, using the old as well as the more recent reports as principal references"

Jan 1, 1970

By P. M. Pearson

This paper describes the principles ()f systems engineering and their application to the various transport problems confronting the mining industry. The organization of mining operations into sub-system design problems is explained.

Jan 1, 1970

By A. Kapoor, L. Morin, S. Mortazavi, P. Béedard, Gould. W. D., A. Kuiper

The degradation of thiocyanate in a simulated gold mill effluent was studied using a laboratory scale rotating biological contactor (RBC). Complete SCN- removal was obtained at temperatures of 8 and 12°C, and a hydraulic retention time of approximately 3.3 h. The NH4+ produced by thiocyanate hydrolysis was oxidized by nitrifying bacteria to NO2 and NO3-. The HS- produced by thiocyanate hydrolysis was chemically and biologically oxidized to elemental S, which was subsequently biologically oxidized to sulfate. Incomplete sulfur oxidation occurred in the RBC, particularly at 8°C and elemental sulfur deposition was observed on the RBC disks. The RBC feed exhibited toxicity to rainbow trout but the RBC was effective in removing the acute toxicity of thiocyanate.

Jan 1, 2005

By Lloyd W. Trevoy

Syncrude Canada Limited is presently studying commercial production of heavy minerals from plant tailings of the openpit A lhabasca tar sands operation. When tar sands are processed and upgraded to synthetic crude oil, heavy minerals can be removed f rom the extraction circuit and beneficiated to provide concentrates of zircon and titanium minerals. Calculated recovery rates indicate that crude oil production capabilities of 105,000 barrels per day would provide 26,000 tonnes of zircon and 114,000 tonnes of titanium minerals annually. The titanium minerals concentrate is a mixture of ilmenite, leucoxene and rutile; it could be used as recovered or upgraded to synthetic rutile. With the consrruction of further synthetic crude oil plants in Western Canada, a large reserve of heavy minerals will become available.

Jan 1, 1984

By V. G. Papangelakis, G. A. Moldoveanu

"Rare earths adsorbed on clay minerals are easily recovered via ion exchange during leaching with inorganic monovalent salt solutions. The leaching efficiency of various salts at 0.5M and 25°C was investigated as a function of cation type and salt system (sulphates vs. chlorides). (NH4)2SO4 was identified as the lixiviant of choice and a procedure was established to investigate the influence of lixiviant concentration, temperature, pH and agitation on desorption kinetics and REE extraction levels. It was determined that the kinetics were fast and the optimum leaching conditions (for >80% total REE extraction) required pH below 5 and moderate temperatures (<50°C). INTRODUCTIONRare earth elements (REE) are at the core of numerous advanced applications due to their various uses in high strength permanent magnets, lasers, automotive catalytic converters, fiber optics/superconductors, and electronic devices (as phosphors in TVs and display screens for computers and cell phones). Because of the ongoing development of new technologies, there is an increased demand for REE in the international market, with emphasis on identifying new resources to insure an adequate supply for present and future use. World production of rare earths is dominated by China, the United States and Australia; however, in terms of resources, China dominates the world potential with reserves estimated to be over 90% of the total (Chen, 2011).The main commercially significant REE sources, as reviewed by O’Driscoll (1991) are bastnasite (carbonate) and monazite (phosphate) minerals, containing up to 70% wt. rare earth oxides (REO). In spite of being high grade, these ores are associated with elevated recovery costs due to difficulty in mining, separation and beneficiation. Moreover, aggressive conditions are required to solubilize the REE from the mineral, such as leaching with hot, concentrated acids or baking in 70% NaOH (Gupta & Krishnamurti, 2005)."

Jan 1, 2012

By R. P. Charbonnier

"To understand the operation of jigs and other separating processes based on differences in gravity, it is desirable to analyse the motion of various particles in given media under specific conditions. A summary of the earlier theories shows that they lead to unsatisfactory or excessively complicated formulae in cases such as coal jigging. By adopting a simplified theory of the motion of particles in a fluid, the size and duration of the initial accelerated motion of a particle falling in hindered settling can be calculated. Based on this mathematical analysis, examples referring to actual coal jigging practice show that it is desirable to prolong and/or repeat, as frequently as possible, the optimum conditions corresponding to an effective acceleration of the particles. The separation is then obtained according to gravity rather than to particle dimensions, as would be the case if the velocity of the particles• were allowed to approach its terminal value. To achieve this gravity separation, it is suggested that the suction phase of the jigging cycle be artificially prolonged and the frequency of pulsations increased as much as possible for washing the coals of smaller sizes."

Jan 1, 1959

By J. Trojacek

A large-scale development in exploration and production of uranium ores in the Czech Republic was done in the 2nd half of the 20th century. Many uranium deposits were discovered in the territory of the Czech Republic. Over a period of 50 years approximately, 110 000 tons of uranium in concentrate were produced. Different mining methods were developed and used. One of the most considerable deposits in the Czech Republic is the site Hamr na Jezere ? Straz pod Ralskem where both mining methods ? the underground mining and the acidic in-situ leaching ? were used. The extensive production of uranium led to widespread environmental impacts and contamination of groundwaters. Over the period of ?chemical? leaching of uranium (ca. 32 years), a total of more than 4 million tons of sulphuric acid and other chemicals have been injected into the ground. Most of the products (approximately 99.5 %) of the acids reactions with the rocks are located in the Cenomanian aquifer. The contamination of Cenomanian aquifer covers an area larger than 27 km2. The influenced volume of groundwater is more than 380 million m3. The total amount of dissolved SO4 2- is about 3.6 million tons. Approximately 0.5 % of the contamination is located in the Turonian aquifer. After 1990, a large-scale environmental program was established and the Czech government decided to liquidate the ISL Mine and start the remediation in 1996. The remediation consists of contaminated groundwater pumping, removing of the contaminants and discharging or reinjection of treated water. The objectives of the remedial activities are the followings : to restore the aquifer to a condition guaranteeing continuing usability of Turonian water of Northern Bohemia Cretaceous, to decommission boreholes and surface installations and to incorporate the surface of leaching fields into the ecosystems taking into account regional systems of ecological stability and urban plans. Nowadays four main remedial technological installations for reaching of these aims are used - the ?Station for Acid Solutions Liquidation No. One?, the ?Mother liquor reprocessing? station, the ?Neutralization and Decontamination Station NDS 6? and the ?Neutralization and Decontamination Station NDS 10?. Total capacity of this complex is sufficient to reach the target values of remedial parameters in 2037. The remediation action consists of: pumping of residual solution to the surface, separating uranium from the solution and reprocessing contaminants into commercially usable or ecologically storable products. It is expected that the amount of withdrawn contaminants will vary from 80 000 to 120 000 tons per year. Total costs of all remediation activities are expected to be in excess of 1.5 billion EUR.

Aug 1, 2013

By C. A. Young, H-H. Huang, L. G. Twidwell

Solid particles, especially oxides/hydroxides, develop an electrical charge on their surface when submerged in aqueous solution. Parks was able to relate PZC (point of zero charge) of an oxide to its minimum solubility and isoelectric point. Dzombak has compiled an extensive database for adsorption reactions on ferrihydrite surfaces using the double layer theory. The equilibrium calculational program, STABCAL has been used to extend the considerations of Parks and Stumm. The PZC for many hydroxides, complex oxides, and non-oxides have been investigated and the results are reported in the literature. Removal of arsenic and metals by adsorption on ferrihydrite as the substrate has been computed using ST ABCAL and the computational results are compared to experimental data. Absorbents other than ferrihydrite such as aluminum hydroxide are also discussed.

Jan 1, 2005

By S. Kelebek, E. Yalcin

"Diethylenetriamine (DETA) and/or triethylenetetramine (TETA) are reagents that can generally be categorized under ""flotation modifiers"". These polyamines are known to be effective for the deactivation/depression of pyrrhotite that is present in Canadian nickel-copper sulphide ores in large quantities. Recent bench scale testing on some of these complex ores indicated that chalcopyrite flotation can also be adversely affected under certain conditions involving polyamines, which may be taken to be an evidence of their specific affinity towards chalcopyrite. In general, DETA shows no significant depressant action on chalcopyrite while TETA&apos;s promotion of hydrophilicity for this mineral has been observed even in the presence of xanthate. This prompted an investigation on thermodynamic equilibria involving these polyamines and copper ions. Results serve a useful purpose to identify conditions for deactivation phenomena. CuDETA2+ and CuTETA2+ chelates as products of sequestration have large predominance areas covering a wide range of redox and pH conditions, where copper xanthate species are not stable, especially in the presence of TETA."

Jan 1, 2009

By John A. Dresser

Seventy years ago a period of prospecting and mining activity began in the Eastern Townships of Quebec that seems to have been quite equal to that of recent years in the Rouyn field. In the following six or seven years a large amount of work was done over a widespread area. About fifty deposits gave some shipment of ore, from a few tons upwards, and as many as five hundred occurrences of copper were made known in the district by official records. Comparing the scale of commercial undertakings of that time and of the present day, these developments must have occupied quite as large a share of the capital and man-power of the Province as northern Quebec employs today. Working conditions at that time were not very favourable. The country was then only newly opened for settlement, and colonists were few and widely separated. Roads of the class built today were unknown. A single line of railway, the Grand Trunk, crossed the district from east to west. Colonization companies controlled large blocks of land on which they owned mining rights and usually reserved these rights in whole, or in part, when selling the lands. Then, as now, the precious metals belonged to the Crown. Yet the work was not without its successes. One of the first deposits discovered, the Acton, was, for a few years, one of the most profitable producing copper mines of its time. Another, the Eustis mine, has been in almost constant operation ever since, and is now vigorously pushing further development. At least two others, now quiescent, proved profitable operations, and several made considerable production. The manufacture of sulphuric acid in Canada was begun by the founder of the Nichols Company at Capelton, on a deposit that is now being re-developed, after a long and creditable career.

Jan 1, 1928

By Dong-kil Lee

A ventilation improvement index (VII) was developed in an effort to propose an optimal ventilation improvement measure for a designated mine. The index was designed to incorporate both ventilation effectiveness and cost efficiency. To verify the effect of the index, a mine experiencing a ventilation problem was selected, the ventilation assessed and ventilation network analyses were conducted. In the selected mine, four areas with ventilation difficulties were detected and an improvement schemes for each area were proposed. These were simulated through network simulation and evaluated using the ventilation improvement index. As a result, an optimum ventilation improvement scheme was proposed. The improvement scheme with the highest VII value was incorporated in the design.

Aug 1, 2013

By Roméo Roussin

"The yearly production from the Asbestos Hill pit is 1,550,000 tons of asbestos ore, with a yield varying between 18 and 20 % . The orebody was exposed at the top of a hill, and initial production started without having to remove any overburden. The projected ratio of barren rock to ore, based on the present orebody, was 2 to 1. However, as it was necessary to push back the upper benches, this ratio has changed to 3 to 1. The final pit will be 2,300 feet long by 1,000 feet at the longest and widest points. The final depth will be 680 ft. A pit slope stability study was carried out and an average wall angle of 60-70 degrees must be maintained. Preshearing of final pit limits will produce good wall stability. Permanent access ramps will be 60 ft wide, with an 8 % maximum grade. Geological conditions and the low rock temperature are the major causes of the operation's drilling and blasting problems."

Jan 1, 1976

By B. Krysa, J. Qiu

The zinc pressure leach plant at HBM&S&apos;s operations is now in its fifteenth year of operation. Current pressure leach operation is steady at a concentrate processing rate of around 26.5 tonnes per hour. A new cellhouse with a design capacity of 124,000 tonnes per annum and the capability of expansion of up to 154,000 tonnes per annum was commissioned in July 2001. The potential to expand the capacity of the pressure leach circuit and associated processes, as well as the purification circuit and casting plant, to meet the maximum capacity of the cellhouse has been investigated. This paper reviews current operation of the zinc plant, as well as the possibility of a capacity increase without major process modifications or major capital expenditures.

Jan 1, 2008

By D. K. Matlock, D. J. Hamre, J. G. Speer

Ultrafine ferrite (UFF) grains may be produced in surface layers of plate steels using controlled intermediate cooling followed by deformation. Experiments were conducted using a 0.12 C - 1.26 Mn steel on a Gleeble 1500 hot deformation simulator. Taguchi designed experiments were used to evaluate prior austenite grain size, intermediate cooling rate, intermediate cooling temperature, intermediate hold time and amount of reduction in order to observe the effects of variables and their interactions on the final microstructure while minimizing the number of required test runs. Evaluation of resulting microstructures and mechanical properties revealed a preferred thermal and mechanical history for developing ultrafine microstructures in surface layers of plate steels. Application of the fundamental concepts of phase transformations to industrial plate rolling is considered.

Jan 1, 2004

By C. Mattich, Å. Holmström, L. Hedström

"The fluidized bed at Division Ministro Hales (DMH) division of Codelco in Calama, Chile is currently the largest operating roaster for partial roasting of arsenic rich copper concentrates. The roaster converts the Mina Ministro Hales (MMH) enargite rich (Cu3AsS4) copper concentrates into calcine with a low arsenic content that is suitable for mixing with other copper concentrates feeding a flash furnace. The plant sets a new standard for the processing of arsenic rich concentrates, both from the quality of the calcine as well as the environmental performances. The process technology and expertise are based on the solid practical experience of treating arsenic rich concentrates from both the Boliden smelter and Outotec.The partial roasting process is located next to the mine and concentrator and includes a sulphuric acid plant with auxiliary equipment. The produced calcine has an arsenic content significantly below target and the residual sulphur meets the requirement of the flash furnace. The plant operates with high efficiency cyclones resulting in a low amount of calcine passing to the hot electrostatic precipitator (HESP). The small flow of HESP calcine dust can be combined with the low arsenic calcine and still meet the flash furnace feed arsenic requirements.SO2 formed during roasting is converted into sulphuric acid, while volatized arsenic is recovered in the wet gas cleaning section of the acid plant along with a large proportion of antimony present in the MMH concentrate. Arsenic is stabilized as calcium arsenate and sent to disposal at a specially prepared site.The present production rate (September/October 2015) is close to or higher than the original maximum design capacity of the plant.INTRODUCTIONMineralogyThe mineralogy of an ore and concentrate is important, since there is a direct link between roasting performance and concentrate mineralogy. The MMH concentrate has a good combination of minerals that makes the roasting process efficient and flexible. The main minerals are pyrite, enargite and chalcocite (Figure 1). The inert content is about 15% and consists mainly of silicate and alumina based minerals. The lead content is very low and this is desirable, since the presence of even a small amount of lead will cause a substantial increase of sintering during roasting."

Jan 1, 2016

By G Anders

The mucking out of sub-level headings by slusher and by Autoloader is described, and the performance and costs of both methods are compared. The introduction of the Autoloader is taken as an example to illustrate the meth-od used at the mine for evaluating the suitability of new equipment. The consecutive steps in the process are covered in detail -from the preliminary cost analysis and the preliminary estimate of savings and advantages, and the review of these data after a field investigation, through the elimination of dubious factors, and detailed time and performance studies at the property, to the final assessment of the new equipment and an evaluation of the initial forecast. The Autoloader in Operation. 1198 Introduction AT Mattagami Lake Mines Ltd., the mine workings are laid out basically on a pattern of 60-ft.-wide stapes alternating with 60-ft.-wide pillars, with stope lengths varying from 80 to 200 ft. and stope tonnages generally between 80,000 and 200,000 tons. Stapes are drilled off from sub-levels at 60-ft. intervals, with the

Jan 1, 1965

By ANNE FUZESY

Soluble potassium salts in bedded underground salt deposits supply most of The world demand for potassium f or agricultural and industrial use. The potassium salts, sylvite and carnallite, were f irs, noted in drillcores in southern Saskatchewan during The search for oil and gas in ihe early /940s. Problems in shafi sinking beset pioneering potash companies, however, and cominuous production did no, begin uniil 1962. Powsh deposits in southern Saskatchewan occur within ihe uppermost 60 111 of the Middle Devonian Prairie Evaporite a, depths in excess of 900 m. Four groups of po/ash-bearing haliie beds have been distinguished: the Esierha-::,y, White Bear, Belle Plaine and Paiience Lake members. Powsh deposiis extend a jell' kilomeires into Manitoba and south imo orth Dakoia and non heasiern Moniana. Individual potash-rich beds are extensive and consistent in grade and Th ickness. Local th ickening occurs where carnallite is the dominani poiash mineral. Th e preferred ore, sy lviniie, is a clean mixiure of sylvite and haliie. Carnalliie and insolubles are avoided wherever possible because of Their detrimenwl effects on mine stability, grade and refining. Sy lvin ite is exTracted by underground mining or brought TO swjace as brine in solution mining. Poiash is separaiedfrom halite byfloiation or sequential crystallization. The refined produci, potassium chloride, is employed as a fertilizer ingredient as well as in chemical and other industrial capaciiies. The ten poiash mines of Wesiern Canada all are in Saskatchewan and account for aboui 25 per cem of world production. Faciliiies are being expanded, and a new mine and refinery was planned for ihe Breden bury area. Deposiis in Manitoba also were being evaluaied.

Jan 1, 1984

By E. Heikkinen, J. Suikkanen, T. Siren, J. Valli, M. Hakala

Diametrically faced borehole breakout observations are a fairly good indication of magnitude of the secondary stresses acting perpendicular to the borehole. In cases of low in situ stresses, where borehole breakouts are not observed naturally, it is possible to increase the prevailing stress state around the borehole by increasing the rock temperature. When the temperature is increased sufficiently, thermally induced borehole breakouts will occur. By implementing the temperature increase in boreholes located at excavated tunnels, it is also possible to study the effect of the near-field stresses caused by the excavation. The near-field stress state changes as a function of borehole depth, thus increasing the information available from experiment. To study the feasibility of this proposed low cost method, a Borehole Thermal Spalling (BTS) experiment was executed in ONKALO Underground Rock Characterization Facility, in Western Finland in 2014. The first borehole pilot test with the method was conducted in ONKALO at the POSE niche in already at May 2010, with the second pilot test following in August 2010 at Äspö HRL. The major objective of the experiments was to define the trend of the maximum in situ stress component, while also providing knowledge of the in situ spalling strength of the ONKALO rock mass. The stress state in ONKALO is nearly isotropic in horizontal layer, causing problems for the use of more traditional stress measurement methods. With boreholes heated over long interval, the weakest rock parts are observed to fail, thus providing statistical confidence. For these reasons, continuous test sections have an advantage in ONKALO, compared to spatially limited stress measurement methods such as overcoring and hydraulic fracturing. The BTS experiment is conducted in 9 meter deep vertical boreholes located at the POSE niche, situated -345 m depth below the ground surface. The boreholes used within the BTS experiment are located in migmatitic granite, in an experiment area where the surrounding stress state and the rock strength are fairly well known. The prior knowledge of the stresses is favourable for the experiment, as it requires careful planning and iterations to determine the appropriate heating power domain. Too low heating power will not be sufficient to cause borehole breakout, while too high heating power causes breakout in all directions thus making determination of stress direction hard or impossible. The initial state of the borehole and induced borehole breakouts will be monitored using acoustic televiewer logging (ABI) and optical borehole logging (OBI) imaging techniques. Fracture mechanics modelling is used in planning of the experiment, also in back-analysis to link the observed breakout angle to stress state. Both the pilot test in 2010 and BTS test in 2014 resulted in similar borehole breakout direction. The results are in line with so called EDZ & VT1 stress interpretation, revealed the maximum horizontal component bearing the magnitude of 21.5 MPa, with the trend of 166°.

Jan 1, 2015