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By C. R. Fast, G. C. Howard

The loss of fluid to the formation adjacent a fracture governs the areal extent of the fracture and the success of hydraulic fracturing as a production stimulation technique. The three flow mechanisms which control this loss are the result of the viscosity of the fracturing fluid and the permeability of the formation to the fracturing fluid, its wall building properties, and the combined effects of viscosity and compressibility of the reservoir fluid. The effects of these flow mechanisms can be evaluated in terms of a fracturing fluid coefficient, the fundamental concepts of which are developed in the paper. The fracturing fluid coefficient, which may be used in calculating the areal extent of fracturing, affords a direct measure of the effectiveness of fracturing fluids. The area of hydraulically created fractures is in-creased as the coefficient is de-creased. The fifteen-fold variation noted in this coefficient for the commercially available fracturing fluids tested resulted in a six-fold difference m the calculated areal extent of the fracture system.

Jan 1, 1961

By P. Chu, J. A. Finch

The formation of small bubbles in flotation is usually accomplished by the use of frothers, or sometimes is due to the presence of inorganic salts in the process water. The effective mechanism associated with the presence of these solutes is generally considered to be coalescence inhibition. However, recent work has demonstrated that the presence of frothers and salts also reduces the size of bubble at the initial formation stage. In this paper we adapt the same experimental setup to investigate the time that it takes for a bubble to form; for a known system power input, the energy to form a bubble can then be estimated from the time. The hypothesis is that the presence of frother and salt will reduce the time for a bubble to form, which can be interpreted as an added energy component being derived from the solute. Testing different types and concentrations of frothers and salts, the hypothesis is supported: the mechanical energy required to form a bubble decreases by about 10% in the presence of these solutes.

Jan 1, 2015

By P. deH. Eastcott

The paper summarizes a slide presentation made during the CIM Mechanical-Electrical Operators' Conference, held at Sudbury. Ontario, January 25-27, 1977. Its scope has been limited to a few specific aspects of modern Canadian hoisting plant practice that are likely to be of interest to operating personnel. It is intended to serve as a brief review of established methods discuss in more detail the present state-of-the-art and suggest trends that will appear as products during the next few years.

Jan 1, 1977

By J. G. Debanne

MOST company-employed petroleum engineers have in their accounting departments punch-card computers that can perform engineering calculations thirty to three hundred times faster than desk calculators, or they can rent such machines from Computing Service centres. These machines not only eliminate the drudgery of desk calculation but also the risks of human errors. The I.B.M. t 604 punch-card computer of Texaco's accounting department in Calgary has been used for oil and gas property evaluations, curve fitting by least squares, statistical core analysis studies, unsteady-state water in-flux studies, phase equilibrium performance prediction of oil reservoirs, gravity segregation calculations, etc.

Jan 1, 1958

By L. H. Van Loon, E. G. Crayston, A. F. Heather

"IntroductionTHE PROPERTY of Madsen Red Lake Gold Mines. Limited. comprises fifty-eight claims located between Russet and Faulkenham lakes in Baird and Heyson townships of the Patricia portion of the District of Kenora. The mine is seven miles •by road from the hamlet of Red Lake. This latter centre is .connected to the Trans-Canada Highway at Vermillion Bay, Ontario, by provincial highway No. 105 which has a total length of one hundred and thirteen miles.The Madsen property went into production on August 11th, 1938, with a milling plant rated at 300 tons per twenty-four hours. Changes made in the crushing plant during October, 1938, allowed a •finer feed to be delivered to the mill and increased the milling •capacity to 400 tons per twenty-four hours. During 1948, steps were taken to add an additional 400-ton capacity unit to the milling plant. This latter work was completed by May, 1949, giving the present total milling .capacity of 800 tons per twenty-four hours.It was realized in the early 1940's that, eventually, considerable material suitable for backfilling in the mine would be required. As there were no large deposits of gravel or sand anywhere near the mine, officials of the Company considered it advisable to investigate the feasibility of using mill tailings for mine •backfill. Since Madsen mill tailings contain approximately 80 per •cent of minus-200-mesh material, it was not considered practical to use them for underground backfill without first removing the finer material. as the slimes present in a product of this fineness would without doubt preclude any drainage whatsoever. Table I gives a sizing analysis of Madsen mill tailings and Table II a quantitative chemical analysis of the ore."

Jan 1, 1954

By O. A. Ojo, E. Anisimov, A. K. Khan

Electro-spark deposition (ESD) has recently generated a great deal of interest in processing aerospace materials. This is due to its potential for joining and repairing difficult-to-weld precipitation strengthened nickel-based superalloys without having problems of welding cracking that often plaque these materials. The short duration of current pulses involved in the process combined with the intermittent contact results in extremely rapid thermal cycle that produces nearly no heat affected zone in the substrate material. The microstructure of electro-spark deposited superalloy was meticulously studied in this work by scanning electron microscopy (SEM) and analytical transmission electron microscopy (TEM). The results show that in contrast to general assumption, the extreme rapid cooling rates involved in the ESD process did not produce partition-less solidification that is devoid of second phase microconstituents in the material. The secondary microconstituents were found formed along the intercellular regions of the solidification microstructure. The nature of these particles and the possible implication of their formation on mechanical properties of ESD processed material are reported and discussed.

Jan 1, 2015

By John Taylor

"The Highvale Mine in Alberta is owned by TransAlta Utilities Corpora/ion and operated by Mana/fa Coal Lid. It is the largest coal mine in Canada and in 1982 supplied 8.6 million 1onnes of sub-bituminous ""B"" coal to TransAlta's Sundance Ceneraling Plan/. Annual produclion is scheduled to increase in 1983 when the firs/ unit of the new Keephil/s Generating Plant comes on stream and is expec/ed to exceed 11 million tonnes by 1985 when the second unit is commissioned. Coal is mined from several pits in a multi-seam operation. Comprehensive maintenance, drainage and environmental programs form a major part of the operation.IntroductionThe Highvale Mine is located eighty kilometres west of Edmonton, Alberta on the south shore of Lake Wabamun (Fig. I). The mine is owned by TransAlta Utilities Corporation (T.A.U.) and is operated by Manalta Coal Ltd. In 1982, 8.6 million tonnes of coal were supplied to T.A.U.'s 2100 MW Sundance Generating Plant, making it the largest producing coal mine in Canada. By 1985, with two 375 MW units on line at T.A. U .'s new Keephills Generating Plant, annual production is estimated to exceed eleven million tonnes. The generating plants accept crushed unwashed coal from the mine via the coal handling plant system conveyor belts. The coal is classified as sub-bituminous ""B"" and has an average heating capacity of 18.6 MJ I kg.HistoryPrior to 1943 only small scale mining took place in the Highvale area. Between 1943 and 1961 two strip mining companies, Mount Royal Collieries and Continental Collieries operated on the present mine site. Both operations excavated coal along the south shore of Lake Wabamun."

Jan 1, 1985

By Cheryl Devine, Radhakrishnan Mahadevan, Vladimiros G. Papangelakis, Srinath Garg

The microbial-mediated recovery of valuable metals locked in mining wastes presents an economical alternative to conventional hydrometallurgical processes. The present study investigated the bioleaching response of a low-grade nickeliferous pyrrhotite tailings (0.6 wt% Ni) and an upgraded pyrrhotite tailings (1 wt% Ni) produced by Vale Base Metals in the Sudbury Basin of Ontario, with the ultimate aim of maximizing Ni recovery. The initial part of the study focused on the bacterial adaptive evolution protocol, by repeatedly sub-culturing an indigenous culture from an acid mine drainage site on 2% (w/v) pyrrhotite tailings. The results showed that the extent of Ni dissolution is positively correlated with microbial activity. Microbial profiling revealed A. ferroxidans to be the dominant member of the microbial consortium. The enriched culture was used for optimizing the growth medium by varying the concentration of essential growth nutrients. Finally, an aerated biotic and abiotic leach of a 10% (w/v) upgraded pyrrhotite tailings with and without pH control, showed a higher recovery of Ni in the pH controlled experiments. These results demonstrate that a high concentration of the oxidant Fe3+ in solution promotes the dissolution of Ni. Furthermore, the sulphide conversion into So was found to be higher in the pH controlled experiments (32%), relative to the experiment without pH control (10%).

Jan 1, 2015

By L. Becze, B. Pierre, S. Di Carlo, G. P. Demopoulos

From January to June 2007, the autoclave production at the Kidd Metallurgical Site was severely affected as a result of plugged discharge lines and extensive precipitation/crystallization of sulphates that caused massive scaling in different autoclave compartments. Work was performed at McGill University to understand the root causes. The crystallization of zinc and ferrous sulphate salts was investigated in terms of solubility measurements. Scale samples were characterized using chemical and mineralogical-spectroscopic analysis. In this paper, following a description of the Kidd zinc pressure leach operation, highlights from this investigation are presented and solutions used to overcome the problem are outlined.

Jan 1, 2008

By A. G. Slade

"This paper deals with the direct application of rock mechanics in the underground mines at the Sudbury Operations of Falconbridge Nickel Mines Ltd. It covers mining methods, the use of photoelastic models, the fore-casting of rock strains and their elimination, closure methods and other common methods of ground control.INTRODUCTIONROCK MECHANICS IS A STUDY IN ROCK BEHAVIOUR and, although it is being termed a new science, it has been practiced since the industry began. Every person involved with rock excavations, from the mine superintendent to the stope driller, is actually practising rock mechanics. They probably call it by another name -experience, and applications of this knowledge are in evidence throughout the Falconbridge operations. Only in recent years have formal rock mechanics studies been employed to provide technical assistance to the mine operators in their primary objective of producing ore safely."

Jan 1, 1968

By Alan Galley, Tom Hynes, Michel Plouffe

"Mining in Canada’s economy• Employs 320,000+ workers; Wages 30-60% above other sectors• Operates 220 producing mines, 33 smelters and refineries• Paid $8.4B in taxes and royalties to governments in 2010• Invests about $30B in capital projects annually • Largest private employer of Aboriginal Canadians 2• Core supplier to clean-technology sectors• Attracted 18% of world exploration spending in 2010• Efficient TSX processes - 1400 mining companies listed, ~50% of mineral projects are outside Canada• Estimated 1000 Canadian companies in 100 countries• Minerals account for 21% by value of Canada’s goods exports• Top 5 World Producer in uranium, potash, nickel, platinum, aluminum, diamonds, zinc, met coal"

Jan 1, 2012

By K. Ohto, B. B. Acihikari, H. Kawakita, M. Gurung, S. Alam

Two kinds of adsorbents were prepared from persimmon tannin extract to investigate their adsorption behavior of metal ions from hydrochloric acid solution; one was prepared by treating with concentrated sulfuric acid while another was prepared by immobilizing functional groups of quaternary amine. The former adsorbed only gold(III) and its maximum adsorption capacities was evaluated as high as 1510 g/kg while the latter adsorbed not only gold(III) but also palladium(II) and platinum(IV), the maximum adsorption capacities of which were evaluated as 820, 89 and 101 g/kg, respectively. For both adsorbents, practical adsorption of base metals was not observed.

Jan 1, 2011

By Michael Moser, Brighty Dutta, David Dreisinger

"Molybdenum is widely used in the industries as an alloying element in the manufacture of steels and super alloys. The widespread use of the element encourages a growing need to develop extraction processes for recovery from both primary and secondary sources. The Solvay Group has developed a solvent extraction reagent named CYANEX®600 for the recovery of molybdenum from acidic solutions originating from both low grade (e.g. copper solvent extraction raffinates, smelter dusts and slags) and high grade (molybdenite) molybdenum sources. CYANEX®600 is a purified form of CYANEX®272 with the active component bis(2,4,4- trimethylpentyl)phosphinic acid. The extraction behavior of CYANEX®600 towards molybdenum in sulphuric acid medium was evaluated. The uptake of molybdenum increased with the increase in concentration of CYANEX®600. The approximate stoichiometry of the extracted complex was: Mo: CYANEX®600 = 1:2. Efficient back-extraction could be achieved with 0.1 M disodium EDTA and 0.1 M (NH4)2CO3, thus providing the option of recyclability of the extractant. The detailed back-extraction studies are currently under progress to find out the possible option for complete transfer of Mo(VI) to the aqueous phase so that high purity Mo salts could be precipitated from the molybdate solutions.INTRODUCTION Molybdenum (Mo) is one of the world’s valuable metals and is highly sought after by researchers due to its versatile mechanical, thermal, chemical properties. Swedish scientist Carl Wilhelm Scheele demonstrated molybdenite to be a mineral sulfide in 1778. Peter Hjelm successfully isolated dark metal powder from the mineral sulphide and named it as ‘Molybdenum’ in 1782 (Gupta, 1992). Molybdenum is a refractory metal of silver gray appearance and is an important alloying element used in the manufacture of steels and super alloys. Molybdenum compounds are widely used in formulation of catalysts (Gupta, 1992). Molybdenum occurs in nature only in chemical combination with other elements. Several molybdenum bearing minerals have been identified, but the only one of commercial significance is molybdenite (MoS2). As molybdenum is a strategic metal for the industrial sector, its widespread use acts as a factor for depletion of the natural resources. Hence, there is growing need to develop extraction procedures for its recovery from both primary and secondary sources. United States, China, Chile, Canada, Peru, and Mexico are listed as the main producers by the U.S. Geological Survey, 2016 (U.S. Geological Survey, Mineral Commodity Summaries, January 2016)."

Jan 1, 2017

By A. H. Lang

"The Cordilleran region of western Canada includes most of British Columbia and the Yukon and pares of Alberta and the Northwest Territories. The western part of this region was for about 50 years the principal mineral producing area of the Dominion. It lost this distinction in 1907 when production from the mines of the Canadian Shield took the lead, but it continues to provide about 15 percent of the total Canadian production. In 1945 the total mineral production of British Columbia and the Yukon was valued at $65,302,900, of which about 80 percent was derived from metals.This paper is intended to serve as an introduction co the more derailed Cordilleran papers. Part I includes a brief synopsis of the complex geology and diverse types of mineralization in the region and Parr II collates the main structural principles exemplified in the derailed papers, and draws some conclusions regarding the application of this information to prospecting."

Jan 1, 1954

By P. A. Riveros

The literature on the arsenic disposal practices of the metallurgical industry and the long term stability of the disposed arsenic compounds were reviewed from a Canadian perspective. The review was complemented with visits to selected operating metallurgical sites to obtain information on their specific arsenic disposal practices and the behaviour of their impounded residues. The arsenic disposal procedure currently favoured by the industry involves the formation of an insoluble ferric arsenate compound which is allowed to sediment at the bottom of tailings or residue ponds. It has been shown recently that this poorly formed crystalline compound is similar to ?arsenical ferrihydrite? which is ferrihydrite containing strongly adsorbed arsenate anions. Despite concerns about its long term stability on thermodynamic grounds, arsenical ferrihydrite appears to be stable for many years in the proper environment which includes a slightly acidic pH and oxidizing conditions. A high Fe/As ratio and the presence of heavy metals appear to increase the stability of arsenical ferrihydrite. High temperature operations, such as those encountered in the autoclave treatment of refractory gold ores, are conducive to the formation of scorodite, FeAsO42H2O, and/or a series of ferric arseno-hydroxy-sulphate compounds depending on the solution composition. Scorodite has several advantages over arsenical ferrihydrite as a disposal compound including a lower iron demand, a higher density and a greater thermodynamic stability. New procedures have been developed to generate scorodite at ambient pressure. These procedures would offer significant reductions in capital cost because of the elimination of the need for autoclaves. Lime precipitation which was widely used in the past is being abandoned as a result of strong evidence showing that calcium arsenate compounds decompose slowly in contact with atmospheric CO2 to form calcium carbonate and soluble arsenic acid. In all cases, the long term stability of the disposed arsenic compounds depends on a number of factors including disposal site characteristics, particle crystallinity and size distribution, the presence of complexing agents and the effect of bacterial activity.

May 1, 2002

By P. R. Brito-Parada, A. Norori-McCormac

Positron emission particle tracking (PEPT) has become an important tool for flotation research, as it is able to resolve directly the behaviour of particles in laboratory scale flotation vessels. The first applications of PEPT to flotation showed only the motion of an individual particle in the pulp and the froth, but nonetheless allowed interpretations of behaviour not previously possible. Since then, PEPT measurement and data analysis techniques have improved significantly and now ensure a high level of confidence in the particle behaviour obtained. In particular, statistical analysis of long-duration experiments allows time-averaged data to be collated, ensuring spatial accuracy and allowing rigorous comparison of different conditions. It will be shown that these PEPT techniques can be used to compare directly the effect of operating conditions and particle properties in a laboratory flotation system. Particle tracks will be illustrated, as well as analyses of particle speeds, average flow streamlines and occupancy that show marked differences in behaviour near the interface and impeller.

Jan 1, 2015

"ALTHOUGH Canadian metallurgists have long been active in research, the scope of the work was somewhat limited until the be-ginning -of World War II. The rapid industrial development of Canada during the past ten years has been accompanied by .a similar upsurge in research. However, the wide geographical distribution of the research centres has made it difficult for the individual research workers to meet together and to exchange ideas or even to learn what projects .are being investigated or the nature and extent of the facilities available for work of this kind.The purpose of the present symposium is to assemble data relating to projects under investigation and the facilities employed at the various metallurgical research laboratories in Canada, thus providing some measure of correlation so that workers in different locations may learn what kind of work •is being .done at other points throughout the country.In reporting the symposium it has not been possible to reproduce the papers in full, but excerpts have been selected that give the essentia1 data."

Jan 1, 1952

By L. C. So, S. Faucher, S. Mostaghel, A. Triwahyuono, D. Sauter, S. -Y. Oh, S. K. Lee, K. Aswin

"Molten hauling and water granulation are the commonly used slag treatment methods in the production of nickel. Water is present in these processes either to accelerate cooling of the dumped slag or in the granulation itself which creates an inherent safety risk of explosions. Even good design and operation are not sufficient to prevent explosions or injuries from occurring. Several dry methods to treat slags have been intensely studied. However, most of these technologies have never been commercialized due to numerous challenges including scalability, cost, low heat recovery efficiencies, and difficulties in heat utilization. Ecomaister-Hatch has recently developed and commercialized a reliable and simple Dry Atomization process, which eliminates water and allows for heat recovery. As part of the development towards other sectors, laboratory-scale and pilot-scale trials have been completed in a number of base metals and PGM facilities. Recently, Dry Atomization of a nickel laterite slag was successfully demonstrated at the laboratory-scale. The current paper introduces the technology and reports the test results obtained from atomization of the nickel slag.INTRODUCTION The processing of nickel laterites produces vast amounts of slag with over 90% of the feed to the furnace reporting as slag. Slag handing is therefore of critical importance to a laterite smelter. Traditionally there are two ways in which the slag is handled (1) Molten hauling, dumping, cooling and quarrying (2) Water granulation, dewatering, stockpiling. There are inherent disadvantages of both methods that will be outlined in this paper. An alternate route of Dry Atomization provides distinct advantages over the two conventional routes that are of particular interest to the nickel producer such as elimination of molten hauling, dumping and quarrying, elimination of water and improved safety. There is also the potential to convert the slag, which is typically regarded as a waste product, into a value added product and the continuous nature of slag tapping makes it amenable to heat recovery. Hatch has recently conducted laboratory-scale test work on laterite slag to demonstrate its viability for Dry Atomization. Results of this work are presented."

Jan 1, 2017

By H. McIntire, R. Preston, D. Roberts

"Repeated 3D terrestrial digital photogrammetric surveys were conducted on hard rock mine pillars to characterize damage during secondary mining. Damage was quantified by measuring Depth of Failure, DOF, from spalling material and crack intensity, D21. These damage values were then correlated to visually assessed Pillar Damage Ratings and numerically estimated pillar loads. Measured damage, particularly Depth of Failure, correlated well with Pillar Damage Ratings. Numerical predicted pillar stress vs. damage exhibited the expected trend with shorter pillars being stronger. High resolution photographs and 3D models were also used to characterize damage mechanisms, which were found to be structurally constrained. INTRODUCTIONThe Doe Run companies Southeast Missouri Operations consists of six room and pillar lead mines (Brushy Creek, No. 29, Casteel, Buick, Fletcher and, Sweetwater) (The Doe Run Company, 2014). The mines are hosted in the Carbonates and Shales of the Viburnum trend with mining depths varying from 180 to 300 m. Pillars are commonly cut square with widths varying from 7 to 9 m and heights generally between 5 and 18 m, resulting in extraction ratios between 80 and 85% (Roberts et al., 1999). Figure 1 presents an idealized stratigraphic section through the Viburnum trend and Figure 2 shows a plan view of the five areas spanning the three mines included in this study."

Jan 1, 2015

By P. R. G. Brandão, E. E. Ferreira

The presence of metallic cations in solution will affect the aggregation or dispersion of the fine hematite particles, depending on the type of cation adsorption: either specific or non specific adsorption. In this work, the zeta potential measurements were carried out on a sample of pure hematite as a function of pH and metallic cations concentration (Ca2, Mg2+, Mn2+, K+, Na+ and Al3+). The objective of these studies was to clarify the effect of these metallic cations on the surface chemical properties of pure hematite. The cations K+ and Na+ adsorbed as non-specific species and caused only the reduction on the values of zeta potential (in terms of absolute value) over the entire range of pH values tested. For the Al3+ cation, in the acidic pH range it adsorbed as a specific species and increased the zeta potential values. The cations Ca2+, Mg2+ and Mn2+, adsorbed as a non specific species at pH levels less than 6.0 and caused the reduction of zeta potential due to the compression of the electrical double layer. However, for pH values greater than 6.0, these cations adsorbed as a specific species causing the zeta potential to increase and became more positive as the pH value increased (alkaline). This effect could be due to the adsorption of some hidroxy complex species of these cations, which contributed to the positive charge. The effect of metallic cations (Ca2+, Mg2+ and Al3+ concentration, at pH 4.0, 7.0 and 10, showed the following results: a) at pH 4.0, increasing the concentrations of Ca2+ and Mg2+ resulted in on a small reduction in the value of the zeta potential. At this pH, increasing the concentration of A131 cations caused the zeta potential to increase due to specific adsorption of a negatively charged Al3+ hydroxy complex b) at pH 7 and 10, increasing the concentrations of Ca2+ and Mg2+ caused the zeta potential to change its charge from negative to positive.

Jan 1, 2004