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By M. W. Grabinsky, P. B. Tomory, J. Carvalho, J. H. Curran

Many underground mining operations use Split Set friction stabilizer bolts for rock support. Currently, however, little has been done to quantify the effects of various rock mechanics and operational parameters on the capacity of frictional support systems. The strength of Split Sets is usually measured by means of a pull test wherein a jacking force is applied to the bolt and a slip load is obtained. In order to evolve a rational design procedure for this type of support, an extensive database of over 900 pull test results from more than 50 mines through- out North America has been assembled and analyzed. Associated relevant rock mechanics parameters (rock type and quality) and operational details (drilling method, bit size, drive time, time to pull test) were also obtained, as completely as possible, for each test. Analysis of the information has yielded several charts that relate pull-out strength to relevant parameters and simple statistical analyses were conducted where necessary. Quantified distributions for pull-out strength were also produced for several operating conditions. The factors that most significantly affect bolt strength have been identified and specific applications to design are discussed. The information presented will assist mining engineers in designing safer and more economic support using Split Sets.

Jan 1, 1998

By A. A. Rafiei, J. A. Finch

A previous study comparing n-pentanol and the polyglycol Fl50 showed that the two reagents could give the same gas holdup but with different size bubbles. The finding implies that bubble rise velocity depends on the surfactant (frother) type. A study using bubble swarms supported the frother type effect but bubble interactions were a possible confounding factor. This study resolves the question by measuring the rise velocity of single bubbles of 0.8-2.5mm diameter over a distance :::: 300cm in n-pentanol and F 150. It is shown that at typical frother concentrations used in flotation that the rise velocity in n-pentanol remains comparable to that in water alone while in Fl50 the velocity is significantly reduced. The results confirm the suspected impact of frother type. It is illustrated that in n-pentanol the rise velocity does not reached terminal; while in Fl50 it does and this is the source of the velocity difference. Advances

Jan 1, 2009

By M. Buarzaiga

High-pressure acid leaching (HPAL) of nickel laterite ores typically extracts 95% of the nickel and 91% of the cobalt. Impurity elements in the feed, such as iron, aluminium and chromium, also dissolve and can be detrimental to downstream processes. Rejection of impurities within the autoclave is highly desirable. Aluminium and iron hydrolyze, and then precipitate in the autoclave leaving only small amounts that are subsequently removed by precipitation in a neutralization step. The concentration of dissolved chromium can range from 200 to 2000 ppm, depending on the feed composition. Chromium in the liquid phase, usually in the hexavalent state, introduces many problems and can limit refining options. For example, chromium poisons the organics in solvent extraction making SX an expensive option. Also, hexavalent chromium must be converted to the trivalent state before it can be precipitated along with iron and aluminium. Bench-scale work confirmed that mixing small amounts of carbon-base additives, such as coke, with the autoclave feed significantly reduced chromium concentration in the autoclave discharge without any detrimental effects on paymetals recoveries and selectivity.

Jan 1, 2004

By H. R. Hammond, E. Sadar

Cominco is making substantial savings in secondary breaking by replacing dynamite with a new nitrate-based explosive. Compareo with dynamite. the new explosive, known locally as "Fine NCN," is significantly cheaper, more effective and safer to use. It also works better than prilled NCN, which is unsatisfactory for secondary blasting because of inadequate sensitivity, low strength and awkward handling properties. A simple apparatus has been devised for pulverizing prilled NCN to a fineness practical for effective secondary breaking. Blasting systems using cheap detonating cord for initiation have been developed.

Jan 1, 1966

By J. W. Griffith

"The mines in the Bancroft area of southeastern Ontario, a few kilometres west of the town of Bancroft, are in Faraday and Cardiff Townships. Three companies, known as Canadian Dyno Mines Limited, Macassa Gold Mines Limited (Bicroft Division) and Madawaska Mines Limited (formerly Faraday Uranium Mines Limited), with plants capable of handling a total of 4,()()() tons (3,629 tonnes) of ore a day, were at one time in production. A fourth company, Greyhawk Uranium Mines Limited, operated a small mine whose ore was shipped for custom treatment to the nearby Faraday mill. Canadian Dyno Mines Limited ceased operations in June 1960. In June 1963 the Bicroft Mine was closed and a year later Faraday closed because of contract completion. But in 1975, Faraday (now called Madawaska) was re-opened but closed again in 1982. During 1959, the peak year, these four mines produced an estimated 1,100 tons (998 tonnes) of uranium precipitates, which represented nearly 7 per cent of Canada's output for that year(Fig. 1).The deposits occur in pegmatitic granite dykes in a region of high-grade metamorphic and metasomatic rocks. Uranium distribution is usually controlled by the distribution of mafic minerals, particularly hematite and magnetite, and by late fractures. The best visual indicators for uranium concentration are hematite staining in the pegmatite, followed by the amount of mafic inclusions or crystals. The Bancroft area orebodies are the only known deposits of the general pegmatitic class in Canada that contained economic deposits of uranium. The principal radioactive minerals are uraninite and uranothorite. By comparison with many other pegmatitic occurrences, some of the ore bodies are unusually large, persistent in depth and relatively rich in uranium minerals. At the end of 1981, total ore reserves were estimated at 1,500,00 short tons (1,360, 000 tonnes) averaging 0.11 % U3O8."

Jan 1, 1986

By B. Stettner, J. Asante, S. Abraham

The levels of nitrogen in steel produced in various metallurgical vessels vary significantly. For example, the tap nitrogen levels in steel produced in the BOF are around 4Oppm, as compared to 70-100ppm in both DC and AC electric arc furnaces. Given the pressing need to reduce nitrogen levels in steel to satisfy customer demand, IPSCO Inc. has gained considerable experience in controlling nitrogen levels in steel over the course of the last three years. Hence, a cost effective process has been developed through an intensive nitrogen control program from steel melting in the EAF through to the continuous slab casting stage. This paper describes the practices employed at each stage of the steelmaking process that have enabled IPSCO Inc. to reduce and control nitrogen levels in steel.

Jan 1, 2004

By Engineering Staff

In 1958, the Iron Ore Company of Canada decided to proceed with the Carol Project. The ore deposits in the area are part of the highly metamorphosed southern zone of the Labrador Trough. They lie along the shore of W a bush lake, in the western part of Newfoundland-Labrador, 190 miles north of Sept-Iles. The project is designed to mine, by open-pit methods, 17,200,000 long tons of crude ore, grading 37 per cent iron, per year. This ore will be beneficiated to produce 7,000,000 long tons of concentrate, grading 66 per cent iron, of which 5,500,000 long tons will be pelletized. Production is scheduled to commence this summer. Initially, ore will be taken from 45-foot benches in the Smallwood mine, using jet-piercing production drills and large-scale blasting with "slurry" explosives. Four 13-yard electric shovels will muck the broken ore into 100-ton trailer trucks. The trailers will be hauled to two 2,000-ton loading pockets, which feed the ore into 100-ton railcars. Four ore trains, each comprised

Jan 1, 1962

By Stephen Mullowney

Outline ? Setting the stage ? Deal activity ? Q1 2013 update ? Key deal sectors ? Deals by geography ? Outlook for 2013 Key Observations 2012 ? Major retreat in M&A activity ? Glencore-Xstrata deal dwarfs all other deals ? Gold & copper dominate deal activity

May 1, 2013

By E. J. Schwarz, A. A. Winir

"Absolute magnetite contents were determined for asbestos specimens in various stages of milling by using a Faraday-type thermomagnetic balance. Comparison of these results with magnetic ratings (MR) supplied by the mining companies cooperating in this study reveals strong scatter. The main cause of this scatter is thought to be that the MR values were obtained in magnetic fields well below the saturating field of magnetite (5,000 oe). However, only the saturation moment is an intrinsic property and consequently must be used for the purpose of obtaining reliable estimates of the magnetite content. Curie points indicate that virtually pure magnetite and possibly Ni3Fe is present in all samples, and another phase, probably (Cr, Al) magnetite, is present in a few samples. The susceptibility in fields stronger than 5,000 oe is positive and falls in the normal paramagnetic range, whereas sy nthetic chrysotile exhibits weak diamagnetism. This suggests that, as a general rule, the least adulterated natural chrysotile concurs with the samples showing the smallest positive susceptibility above 5,000 oe. The magnetite appears to increase in quantity with a decrease in fibre length and to be somewhat more uniform in distribution for samples showing substantial fiberization (opening of the fibres)."

Jan 1, 1971

By Jean Dugas, Roger Sirois

The Mineral Deposits Service of the Quebec Department of Natural Resources is engaged in the preparation of metallogenic maps as a contribution to the Canadian Sub-Committee of the Metallogenic Map of North America. The preliminary work is being done on large-scale maps. The main objective is to clearly represent information on ore deposits in a suggestive way. The design of the legend to meet these requirements is discussed. As these maps are still only descriptive, a further step will be the interpretation of data into metallogenic maps with Jess emphasis on the individual deposits and more on the metallogenic factors. Both types of map should prove useful in the search for ore deposits; the first by providing at once a large amount of information, the second by suggesting the ore controls.

Jan 1, 1967

By Robert B. Parsons

"Canada doesn't really have a tax system for mining - it has eleven separate tax systems! The consequent maze adds some undefinable margin of difficulty to making investment decisions in Canada. But, this 11U1Ze is not likely to be simplified. Solution: learn it and sell it! Intricate Network of Winding PathwaysWebster's New World Dictionary defines the word ""maze"" as follows: ""a confusing, intricate network of winding pathways; labyrinth ... a state of confusion or bewilderment"". Webster's does not go on to give an example of a maze, but the dictionary could easily have referred to the taxation of a Canadian mining operation. The uninitiated would almost certainly look upon such taxation as a maze of the most perplexing sort.Twenty years ago, Canada's tax system was really quite simple. It is true that Canadian mining profits were subject to three levels of taxation (federal income tax, provincial income tax, and provincial mining tax), but this didn't pose a problem. Prior to 1974, at least the provincial income tax systems were somewhat the same in terms of rules .and rates, and even the provincial mining tax systems resembled one another. Mining profits were subject to pretty much the same rules, no matter what province or territory hosted the mine. Those were the “good old days” one could even dare to generalize about tax rates without fear of being labelled an imbecile!"

Jan 1, 1994

By W. Gordon Muir

This paper deals with the exploration, development and current operations of the salt mine at Goderich, Ontario operated by the Sifto Salt Division of Domtar Chemical Limited. The rock salt is obtained from a bed 1,760 feet below the surface, 75 feet thick, extending under Lake Huron. Annual production is in excess of one million tons. Large mobile equipment is used. Details of this equipment, as well as the shaft layout, which permits the equipment to be lowered underground with a minimum of trouble are outlined. Mining, crushing and screening procedures' are rev1ewed. Reference is also made to productivity salt distribution and uses.

Jan 1, 1967

By Frank Doxley

"FIRST OF ALL I should like to express to the members my sincere thanks for having had the privilege of serving them as President during the year now ending, to the Council for their guidance, and to the Secretary-Treasurer for his untiring efforts on both the Society's and my behalf during my year of office.During the .past five years the Canadian •Coal picture has changed considerably. In the West, production has been almost halved and many mines have been closed, due to the development and expansion of oil and natural gas industries, which, with some imported residual oil -on the Pacific coast -have provided competition which has been impossible to meet. The two major railway companies have embarked on an oil-burning and dieselization .programme and with this has .been lost one of the largest available markets for coal. Natural gas pipe-line installations still further threaten the remaining outlets for Western coal.In the East, retention of markets has also been a •problem, due to the intense competition provided by imported American •coal and the importation of residual oil.Because of cost it is impossible for central industrial Canada to be supplied with .coal from the Maritimes and markets are, therefore, restricted to fringe areas in Ontario and Quebec, and the Maritime Provinces.The dieselization programme of the Canadian National Rail ways has meant the loss of a large market for Nova Scotian coal and it is fair to assume that within a comparatively short time the market will be completely lost."

Jan 1, 1955

By D. C. Downing

"I THANK YOU for the invitation which The Mining Society of Nova Scotia extended, originally to Gordon Berry, manager 'of our Point Tupper Refinery, to join you at this meeting and discuss refining and petrochemicals in their relation to this region. There are natural advantages in Nova Scotia which have made possible, and will continue to make possible, sizeable developments both in petroleum refining and in chemicals. Equally, however, as is the case everywhere, there are certain constraints. For clarity in this presentation, I will state some of these constraints right at the beginning. First, of any future developments from now on, only a small proportion of the products can be expected to go into local markets. I can make the point best with a few figures. Petroleum companies all have market forecasts. None ever work out to be perfect, but the trends are relatively predictable and the orders of magnitude are certainly correct. Estimates for the use of all refined petroleum products in the four Atlantic provinces are:"

Jan 1, 1973

By C. J. Hodgson

"IntroductionThe Kitsault molybdenum mine is located 600 m above sea level on Lime Creek at the head of the inlet of Alice Arm, 140 km northeast of Prince Rupert, British Columbia (Fig. 1). The area of the mine is characterized by rugged topography and deeply incised creeks which drain into the Portland Canal - Observatory Inlet fjord system. Access is by air service or boat from Prince Rupert, or by secondary road from Terrace.HistoryThe deposit was first staked in 1911, at which time the main feature of interest was a polymetallic vein with values in silver located southeast of the molybdenum deposit (Woodcock and Carter, 1976). Turnbull (1916) was the first to describe the extensive zone of crisscross quartz stringers with Mo~ on the banks of Lime Creek which, although it clearly had the potential to contain a major deposit, was not then believed to be of commercial value.Following sporadic work through the 1920s and early 1930s, the ground lay idle unti11959 when Kennco Explorations (Western) Ltd. commenced a program of systematic diamond drilling on the stockwork-type mineralization adjacent to Lime Creek. In late 1964, Kennco announced the presence of an orebody of 36 million tonnes averaging 0.230Jo Mo~ which was to be put into production at a rate of 5450 tonnes per day under a new subsidiary, British Columbia Molybdenum Ltd., at a forecasted capital cost of $20 million (revised to $30 million).Between January 1968 and April 1972, 10.4 million kg of molybdenum were produced from 9.3 million tonnes of ore, at an average mill recovery of 90%, and with an average mill head grade of 0.206% Mo~. The ore was mined in an open pit with a waste to ore stip ratio of 1.5 to 1. The. operation was terminated in 1972 due to weak molybdenum prices and escalating costs.In May 1973, the deposit was purchased by Climax Molybdenum Corporation of British Columbia, Limited and in 1979 transferred to affiliate Amax of Canada Limited. In early 1979, following completion of detailed feasibility studies, Arnax commenced construction of the 10 900 tonne per day Kitsault mine and mill complex based on a mineable open pit reserve of 95 million tonnes at an average grade of 0.192% Mo~, sufficient for a mine life of 25 years. The original capital cost estimate was $143 million; it subsequently escalated to approximately $200 million."

Jan 1, 1995

By John Tribe

"This paper gives the organizational history of Luscar Ltd. and its various coal producing operations. Each 0/ the operations is then described individually. They include the Bienfait Mine, the Boundary Dam Mine, the Diplomat Mine, the Luscar Mine and the Coal Valley Mine. The company's plans/or expansion are also discussed. IntroductionLuscar Ltd. is an Edmonton-based energy company formed in 1967 through an amalgamation of two pioneer coal companies-Mountain Park Collieries and Luscar Coals Ltd. In 1912, Mountain Park Collieries initiated the development of an underground mine in the Coal Branch area of Alberta. This mine necessitated the establishment of a townsite and the provision of rail access. The second operation, Luscar Coals Ltd., was established in 1921 at Luscar, Alberta. This was also an underground operation and required the development of a rail spur and townsite. The product from both mines was used to fuel railway steam locomotives until the 1950's. The market demand for coal decreased as the use of the diesel locomotive increased, so that these operations were finally closed in 1954. Through the amalgamation of the two companies in 1967, however, Luscar Ltd. was formed to become an active participant in the revival of coal operations. Western Canadian Luscar Ltd. is involved in the exploration, development, production and marketing of coal, coal products, oil and gas. Luscar Ltd. is currently participating in five producing mines (Fig. I). The Diplomat Mine, approximately 125 miles southeast of Edmonton, was in production when it was acquired in 1949 by Luscar Coals Ltd. In 1966, the Bienfait Mine and char plant were added. The Luscar Mine, which is a 50/50 joint venture of Luscar Ltd. and the Consolidation Coal Company of Canada, and is operated by Cardinal River Coals Limited, started production in 1969 on the original Luscar Coals Ltd. mine site. The Boundary Dam Mine was opened in 1974. Both the Bienfait and Boundary Dam operations are located in the lignite coal fields of southeastern Saskatchewan. The most recent addition to the group is the Coal Valley Mine, 40 miles southwest of Edson, Alberta. It commenced commercial production in July, 1978 under the operation of Luscar Stereo (1977) Limited."

Jan 1, 1980

By George Langford

Introduction The fiftieth anniversary is, for an individual or a society, an appropriate time for a review of the past so that events and experiences may be viewed m perspective, and thereby serve as a useful guide to the future. In this review of mining geology it is proposed to set forth the situation as it was when the Institute was founded, and then trace the developments during three appropriate periods-the first from 1898 to 1918 the second from 1919 to 1939 and the third from 1939 to 1948. Mining activities were widespread in Canada in 1898 and some of the operations were considered large for their day. The total value of the metals produced in that year was $21,705,854, and in the case of five metals the output had a value in excess of one million dollars. In order of importance these were gold, silver, copper, nickel, and lead. The important producing areas were ova Scotia, Quebec, Ontario British Columbia, and Yukon. This diversification of the mining areas and the metals produced created an interest in mining throughout Canada, and was an important factor in making Canadians conscious of their mining industry. In the year 1898 geology was a recognized science. The principles of physical geology were well known, but the same cannot be said of economic geology and structural geology. Ore deposits and their occurrence had been studied chiefly in Europe. A great many important observations had been made but the theories linking these facts together were still m a formative stage. The same condition was true of structural geology. These two branches of geological science which are so important in what is now called 'mining geology', had not progressed far enough to be of practical assistance mining operations. For this reason, geologists were regarded as dreamers in ivory towers-a concept chat still lingers in the minds of those who have not kept abreast of the growth of the science.

Jan 1, 1948

By M. A. Power

The diamondiferous Drybones Bay kimberlite pipe is the largest pipe (900 m by 400 m) discovered to date in the Northwest Territories. The pipe intrudes granodiorite of the Archean age Defeat Pluton and contains crater, reworked crater (epiclastic) and diatreme facies kimberlite. In-situ measurements of seismic p-wave velocity were recorded with in-line refraction arrays over representative areas. Refractions from fresh kimberlite were recorded over epiclastic facies kimberlite in the eastern portion of the pipe and returned an average velocity of 4300 m/s. Refractions from weathered kimberlite were recorded on all lines and returned velocities ranging from 1900 m/s to 2200 m/s. Granite surrounding the pipe returned an average velocity of 5400 m/s. The results indicate that there is a definite contrast in seismic velocities between kimberlite and country rocks at Drybones Bay and suggest that seismic refraction surveys may be an effective means of screening kimberlite targets in glaciated areas underlain by igneous or metamorphic rocks.

Jan 1, 1998

By Nicholas J. Welham

"The effect of extended ball milling has been studied for two industrial processes: (1) the processing of metal sulphide concentrates; and (2) the carbothermic reduction of ilmenite to synthetic rutile. The plant concentrates were a gold ore with 128 g/t Au of which 8% was non-refractory and a zinc concentrate with copper impurities.The gold concentrate showed complete dissolution of the gold bearing minerals after milling giving almost complete gold liberation. The zinc concentrate showed almost all of the sulphides had solubilized leaving the gangue and elemental sulphur. A study of pure pyrite and arsenopyrite shows that selective dissolution should be possible by a simple leaching process directly after milling.The milling of ilmenite and coal together results in a temperature decrease of 150°C in the subsequent carbothermic reduction of ilmenite, in addition to improving both the rate of reaction and the selectivity of reduction to rutile. IntroductionAlmost all mineral processing plants use mills for the size reduction of particles prior to physical and chemical processing. When continuing beyond size reduction the energy transferred causes deformation, breakage and realloying of particles giving a steady-state particle size. The breaking also causes increasing damage to the crystal structure by formation of smaller grains giving an increasing number of grain boundaries and increasing crystalline defects due to deformation. The increasing number of grain boundaries and defects leads to increased reactivity, which can be seen directly by a reaction within the mill, or indirectly, via a decrease in the subsequent annealing temperature required for reaction."

Jan 1, 1997

By Marc C. Bétournay

"Surface crown pillars, acting to safely protect underground workers and operations from surface elements, are recognized, herein, as distinct from conventional deeper underground pillars. Moreover, because of the variation in mining and geological conditions that exist from mine site to mine site, each case is viewed as unique. A review of numerous case studies and existing literature indicates that there is little general information or systematic problem-solving approach associated with them.A design process, not unlike that of other engineering disciplines, is presented to correct these deficiencies. As part of its purpose, it will inform operators of the key elements required for design and will address the problems of these appendages. The design, while taking into consideration possible surface crown pillar settings and inherent characteristics, is founded on a step-by-step procedure starting with site investigations through to monitoring or pillar recovery. The process is flexible, in that it incorporates decision making and changes in mining strategy. The purpose of each step is explained and each step is extensively described in terms of the required equipment and methods for field work, analysis and support measures. Analytical formulae and studies from several fields directly applicable to surface crown pillars are also given. Recommendations for future research studies are presented."

Jan 1, 1987