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By P. P. Rosario

A research project was conducted at the University of British Columbia (UBC) resulting in the development and evaluation of a novel comminution circuit incorporating autogenous grinding and parallel trains of cone crushers and high-pressure grinding rolls (HPGR). A primary driver for the circuit was to treat ore from deposits with clay and variable hardness. This paper summarizes the unique pilot-plant test program that was developed as a basis for experimental simulation and lists the main findings of the research, including the circuit?s potential operational cost savings compared to a conventional SAG circuit.

Jan 1, 2012

By Victor R. Eyzaguirre

Cerro Verde is one of several large porphyry-type copper deposits in Southern Peru. The copper occurs as primary sulphides, with a significant oxide capping. The exploitation of the deposit has been correspondingly divided into two stages, the first consisting of copper production from oxides, and the second from sulphides. Minero Peru successfully started the Stage I plant in June of 1977 with the first production of electrowon copper cathodes. This paper is essentially devoted to a description of the Stage I process, which can be summarized as follows: Ore is trucked to the primary crusher, where it is crushed to 225 mm and conveyed to a coarse ore stockpile. Ore withdrawn from the stockpile is secondary crushed to 65 mm, conveyed to a truck loadout bin, loaded into trucks and driven to the leaching pads. Ore is placed on the pads in lifts and sprayed with sulphuric acid solution to dissolve the copper. Copper-bearing solution forms a pond behind a dam at the lower end of each pad and is pumped from there to the solvent extraction plant. Copper is extracted from the leach solution into an organic phase and is then stripped from the organic phase to form a purified concentrated copper solution suitable for feed to electrowinning. In electrowinning, the copper is finally recovered as cathodes suitable for sale as refined copper.

Jan 1, 1978

By A. B. Rossetti

"THE MISSION TO Offshore Scotland was in my opinion a very worthwhile venture, as it indicated the scope of the offshore oil and gas business and how we might exploit it to the fullest here in Nova Scotia - if our offshore fields eventually become producing fields. The writer was able to attend a considerable number of lectures and as a result gained some valuable know-how on the engineering design, financing and operation of the North Sea oil industry. There are many new fields of technology that had to be developed to overcome the North Sea's hostile environment and a great deal of the same technology will have to be developed to win oil and gas from our continental shelf. The visit left me with several impressions, which in the main are:(1) The high order of investment required to develop offshore oil. The investment ranges from 10 to 20 times that required for a similar output on land. Each barrel of oil costs on the average of about $2,- 500 per barrel per day.(2) Because of the high investments required, before the first oil is produced the field must be brought into production at the earliest possible date and initial lead time from decision to production is less than four years. In the British Petroleum field, working at a depth of 450 feet will require an investment of $900,000,000 to develop a production of 400,000 bbl per day. (3) The size and complexity of equipment required is beyond anything ever imagined. Problems which must be overcome are such factors as water depth, wind velocities, wave height, wave period, long periods of darkness, low temperatures, distance from land, and fog."

Jan 1, 1973

By J. G. Kelly

"IntroductionOver the past twenty-five years of improvements to scooptrams In the Ontario Division of Inco Ltd., records indicate that on average, an 8 yard capacity machine at 80% availability will load, haul and dump about 100TPH from an average stoping area. This, essentially, means that Inco mines are limited to 2000 TPD as an approximate maximum production cap per minute. Some of the improvements made to scooptrams over this period have been:• dry disc and oil immersed brakes on larger loaders;• to replace air over hydraulic systems;• modulated shift transmissions;• greater breakout and tramming capacities by using larger engines and buckets;• operators' compartments have been enlarged and better seats,• joystick controls and air-conditioned cabs have been utilized'• major cost savings have been realized through tire maintenance improvements; and• major savings, safety improvements and increased ore recovery by using remote controls.After reciting the improvements listed above, and the list is by no means exhaustive, it is quite obvious that scooptrams are a mature product and that major design or performance improvements will not occur in the futre. Any futher improvements will be incremental in nature. Loading, hauling, and dumping with scooptrams is a batch process and as such is limited in its total output.Continuous Load/Crush/Convey Systems:In order to improve productivity, a radical new system was required. The target was 2000 tons per shift. In 1984, to meet the goal, Inco acquired the rights to a contiunous loader from Canadian Mine Services. Inco made modifications to the original prototype machine, such as: (I) conversion from rail mounted to crawlers for increased mobility; (2) a hydraulic cooling system was added; (3) flight bars were changed from cast to forged; (4) motor horsepower increased to 200 hp from 150 hp. Emerging from these modifications came a machine known as the CL-looo Oscilloader (Fig. 1).The CL-looo Oscilloader is an electric hydraulic 35-ton machine which is crawler mounted and has a drawbar pull of 30 tons. It has an adjustable frequency, oscillating lip which simulates the digging action of a manual .shovel. This action agitates and lifts the muckpile enough to allow it to settle by gravity onto the chain and flight conveyor table which then removes the ore to the tail end for discharge into either a crusher, a conveyor, a truck, or a combination of these.Late in 1985, six oscilloaders were fabricated and put into Inco mines for field trials. At Creighton Mine some early field trials were conducted with a rail mounted continuous loader loading directly into 140 cu.ft. Granby cars. Much of the field testing was in VRM drawpoints with the Oscilloader loading into 20-ton trucks or into Teletrams . At Levack Mine, by puttmg the truck on remote control, it was possible to have the operator run the Oscilloader and load his own truck (Fig. 2). At McCreedy West Mine, Copper Cliff North Mine, and Copper Cliff South Mine, the Oscilloaders discharged directly into 26-ton trucks."

Jan 1, 1988

By D. T. White

Pressure acid leaching of nickel laterite ores typically involves the production of an intermediate product that is releached and refined to pure nickel and cobalt products. BHP Billiton is developing the Ravensthorpe Nickel Project to produce up to 50,000 t/y of nickel via a mixed hydroxide intermediate, which will be refined at its Queensland Nickel (QNI) Yabulu Refinery near Townsville, Queensland. The hydroxide precipitation flowsheet has been adapted to process high magnesium ores through an atmospheric leach stage, eliminate iron(III) as jarosite and oxidise iron(II) during neutralisation. The neutralisation conditions are controlled to precipitate aluminium, chromium and silicon, and to ensure good solid-liquid separation. Soluble impurities such as magnesium are purged with the tailings stream and will be managed over the long term by crystallisation in evaporation ponds.

Jan 1, 2006

By D. J. McCulla

Mineral development and utilization affect the health of the economy and the pattern of long-term development throughout Canada. There are many diverse opinions on the contribution of minerals to the economy, but there is a dearth of adequate quantitative information. This paper discusses some recent research and provides some new information.

Jan 1, 1977

By Claudio Acuña, Sergio Romo, Gerardo Fuentes

The leaching kinetics of a zinc concentrate in autoclave reactors were studied. A sample of concentrate from Bolivia, with typical mineralogical characteristics of the Andes region, was used. A concentrate containing 49% zinc and 145 ppm of silver from Minera Viacha was characterized chemically and mineralogically (atomic absorption, X-ray diffraction, and SEM microscopy) and tested in bench scale reactors. Two types of autoclave batch reactors were used at 40 bars of oxygen pressure and three levels of temperature (150°C, 200°C and 250°C). The solid to solution leaching ratio was 1:10 (10% sulphuric acid concentration). The effect of the particle size of the concentrate on the leaching kinetics was studied (P80: 145 and 45 µm). Iron from the leaching solution was removed by precipitation by increasing the pH in order to generate a clean solution for zinc electrowinning. The zinc solution was used to evaluate the feasibility of cathode production at the laboratory scale. Zinc extractions with higher liberation (P80 = 45 µm) reached up to 98%. Ground concentrate with finer sizes resulted in agglomeration and the use of dispersing agents did not improve slurry mixing. The leaching solution contained 55 g/L zinc and 7 g/L iron; it was purified by precipitating iron. The precipitation was evaluated using sodium hydroxide and ammonium hydroxide. In the first case, a colloidal suspension of ferric salts was formed while in the second case, different iron compounds were precipitated. The precipitate obtained with ammonium hydroxide had better filtering properties. Electrowinning was carried out using two types of cathodes (stainless steel and aluminium) and solutions purified with ammonium hydroxide. Zinc cathodes formed on stainless steel presented a better physical quality than those formed on aluminium.

Jan 1, 2015

By Y. Serres

In the past, conventional reflection seismic techniques were not very successful when applied to typical mining exploration: they lacked resolution in the shallow range or were not cost effective. By combining a light earth tamper source, special geophones and field procedures, a stacking process of the returning seismic events using a microprocessor system, and a sophisticated sequence of adapted digital data processing, Mini-Sosie achieves high resolution in the 100-ft to 4000-ft range. Additional advantages result from the very quiet nature of the source and flexibility of the system. Although Mini-Sosie might be used in the refraction mode, or for well velocity logging, it has found its main applications with the reflection technique.

Jan 1, 1978

By W. J. Dick

THE purpose of this paper is to point out, briefly, the importance of the coal mining industry of Alberta and to stress the economic factors that hinder its development; also to offer suggestions relating to the major problems of the industry. The minor problems will not be dealt with in detail, because, if the major problems are taken care of, it is felt that the industry itself can take care of ,he remainder. COAL MINING NO LESS IMPORTANT THAN GOLO MINING The large increase in metal mining development in all provinces of Canada, excepting Saskatchewan, Alberta, and the Maritimes, has had the effect of focussing public attention on this branch of the industry. The fact, also, that this development came at a time of depression has been of immense benefit to Canada as a whole. On account of the necessity and consequent demand for gold, with its attendant increase in price, through government action, from $20.67 per ounce to $35.00 per ounce, it is safe to say that the public of Canada have become, today, gold mining conscious. While everyone admits the great value. of the gold mrn111g industry, nevertheless, the equal value to Canada of certain other industries must not be lost sight of. The coal mining industry, in particular, is worthy of greater public and government support than has been accorded it in the past. It would seem unnecessary to stress this matter to a meeting of the Canadian Institute of Mining and Metallurgy, but unless certain facts are brought to your attention, there is danger that the coal mining industry will not be developed to the extent its national importance deserves. Too many public men and men in authority are unaware of the value of coal mining.

Jan 1, 1936

"Geological investigation in the Appalachian region of Canada began more than 150 years ago. The distribution of rock formations, and their ages and regional structure are today reasonably well known in most parts of the region to 1-or 2-mile scale. Most Newfoundland geology is known only to 4-mile scale. About 200 earth scientists carry out research in the region, of whom about 25 per cent are government employees, 50 per cent university staff and graduate students, and 25 per cent industry employees.Increased activity is needed toward both regional analyses and problem studies through the efforts of multi-disciplinary teams. The ultimate objectives of earth science must be the discovery and development of mineral re•-sources and the use and conservation of natural material in the environment, all for the benefit of the local in-habitants. To accomplish this, the scientific community must carry out an array of research projects ranging from the technical products of geological, geophysical and geochemical surveys through to the research products de-signed to renew theories and hypotheses bearing on natural processes. Some scientific sub-objectives are listed.Recommended is the increase and broadening of communication among Appalachian scientists, specifically those resident in the Atlantic Provinces. It is proposed that an Appalachian Division of the Geological Association of Canada be formed to provide a forum for discussion of Appalachian topics. In addition, a committee or council of university, industry and government earth scientists should be formed to examine the state of the science in the region, to identify programs of investigation and individual projects of research, and to recommend methods of approach. If the committee succeeds and the scientific community acts upon the recommendations, the quantity, quality and pertinence of research will increase, and earth science will better serve Appalachian society."

Jan 1, 1970

By S. A. Scott

In 1913, potash mineralization was recognized at a depth of over 7,000 feet in an oil-well hole (Norcanol's Radville No. 1 well) drilled near the town of Raddlle, Saskatchewan. Although, at this depth, potash is not considered mineable by conventional underground mining methods, this discovery shed the first light on the potash deposits of Saskatchewan in much the same manner as oil-well drilling was responsible for the first discovery of potash in the Carlsbad Basin of New Mexico in 19:25. The discovery near Radville alerted the oil-well geologists and, as a result potash mineralization was recognized in the Verbata No. 2 well, near Unity, Saskatchewan, in 1946. The mineralization, which was at a depth ?of 3,466 feet, graded more than 20 per cent K20 over a thickness of eleven feet. This discovery, as its depth, thickness and grade were all amenable to mining,

Jan 1, 1963

By J. W. Matousek

The heat content of the waste slag from a typical smelting operation methods for estimating the thermodynamic properties of smelting slags, to include: -- heats of formation -- heat capacities (specific heats) -- heat contents -- melting temperatures -- heats of fusion The techniques are illustrated with the analyses of a nickel reverberatory furnace slag from Copper Cliff, an iron-making blast furnace slag, and a "lateritic" slag from a ferronickel operation in Colombia.

Jan 1, 2007

By M. Tiedtke, T. Crary, P. MacPhail, M. Ounpuu

"The SGS carbon-in-pulp (CIP) / carbon-in-leach (CIL) model was used to evaluate and optimize the carbon circuit at Alamos Gold’s Young-Davidson Mine. Plants samples (pulp and carbon) were tested in a series of small scale batch experiments to determine rates of gold leaching and adsorption on carbon from a combined flotation concentrate/tailing product. The testwork data, along with existing plant data were then used to model the performance of the existing CIL plant and optimize the circuit to improve performance and overall recovery. The primary purpose of the modelling exercise was to determine the most cost effective way to lower solution losses at the plant. The modelling was also used to learn how the various parameters in the CIL circuit affect solution losses and the gold inventory tied up on the carbon. This resulted in recommendations for minor changes in the CIL flowsheet, which were successfully implemented in the plant. The approach, results and plant changes are presented.INTRODUCTION This paper presents the details from testwork conducted on samples from Alamos Gold’s Young- Davidson gold mine which is located near the town of Matachewan, approximately 60 km west of Kirkland Lake in Northern Ontario, within the southwestern part of the Abitibi Greenstone Belt. The objective of the test program (completed by SGS Canada in 2013) was to investigate and model the combined flotation concentrate / tailing carbon-in-leach (CIL) circuit and suggest ways to improve gold recovery. The metallurgical test program included mineralogy, rheology, and carbon modelling testwork. Plant information was provided during the test program and used in the optimization process. Upon completion of the testwork, plant changes were recommended and implemented at site (October 2014). Plant results from 2014 to 2017 confirmed the modelling results."

Jan 1, 2018

By S. P. Chong, N. C. Shih, G. A. Turner

Fine powders, with the bulk of the particle diameters Jess than 10 microns, were aerated so that each particle was, on the average, separated from its neighbours by 1.3 to 2 mean diameters. In this state, measurements were made of the viscosity and settling rate of the powder, and the interfacial tension between it and a moist pellet. From the viscosity measurements, qualitative analogies are drawn between the behaviour of the aerated powder and that of a dense gas near its critical point.

Jan 1, 1970

By M. Palfreyman

"Most of the minerals employed in Canadian refractory production are imported; in fact, most of the refractories consumed in Canada are imported. Whereas this situation is partly due to a definite shortage of suitable raw materials, e.g., fire clays, it is possible that the potential of certain mineral deposits which could be usefully exploited has not been recognized. There are exceptions, notably magnesite and dolomite, from which refractories are produced in Canada.In many cases, known mineral deposits are located either in inaccessible areas or in areas where transportation would be a major economic factor. This paper lists some minerals and their respective known deposits which could be employed in the production of refractories, irrespective of economics."

Jan 1, 1973

By W. A. Haley

This paper discusses how a large wheel loader should be equipped, with particular attention paid to tires and tread life, and describes the several steps that can be taken to provide favorable working conditions and reduce over-all costs. A comparison is then made of wheel loader production and costs vs those of power shovels, and the present and possible future applications of the wheel loader are outlined.

Jan 1, 1969

By P. C. Thurston, T. Setterfield, D. H. Watkinson

"The Maybrun copper deposit IS In a succession of pillowed basaltic flows in the Wabigoon sub-province, northwestern Ontario. The rocks have primary flow morphologies and remarkably well-preserved crystallization textures, including quench-textured plagioclase, in spite of metamorphism to the amphibolite facies. The sulphide assemblage chalcopyrite-pyrrhotite-cubanite with minor sphalerite and pyrite is primarily in interpillow spaces and is stratabound. Basaltic rocks immediately enclosing the copper sulphide minerals have an enrichment in Fe, Mg and K and depletion in Ca and Na relative to surrounding flows. The Maybrun deposit is interpreted to have formed contemporaneously with volcanism and alteration, and was subsequently metamorphosed with the enclosing basalts.IntroductionThe association o f significant base metal accumulations with mafic submarine flows in the Archean is as yet poorly documented. Such deposits, where noted, have typically been small, and are therefore commonly over looked. The Maybrun Mine, a 2.6 x 106-tonne copper deposit in pillowed basalt, has many similarities with large, well-documented volcanogenic deposits. Given the interpretation of the Maybrun Mine to be volcanogenic in origin, there is n o reason why similar processes could not produce large deposit s. This is an important realization in an area where Archean submarine mafic rock s are very common, but frequently are examined only superficially. As gold commonly occurs in deposits such as Maybrun, even modest-sized deposits may be economic. The basalts at Maybrun are remarkable for amphibolite-facies rocks because of their extremely well-preserved delicate volcanic textures, including quench textures.The Maybrun Mine is one kilometre south of Atikwa Lake, in the Wabigoon sub-province of the Superior structural province, 75 km southeast of Kenora, northwestern Ontario, at longitude 93°35'W, latitude 49°25'N (Davies, 1973). Archean metavolcanic and metasedimentary rocks and intrusions underlie the area. Goodwin (1970) concluded that the mafic and minor felsic metavolcanic rocks, as well as the overlying metasedimentary rock s, were an eastward extension of the lower cycle of the Keewatin type section for the Lake of the Woods area. He estimated that the stratigraphic thickness of Keewatin rock s in this area is about 6900 m, of which 87% is basalt. The flows contain numerous interlayered sills, predominantly of basaltic composition; they have been extensively folded, faulted, metamorphosed to amphibolite facies and intruded by numerous felsic bodies, most importantly the Atikwa Batholith."

Jan 1, 1983

By R. C. A. Thurston

INTRODUCTION THE deleterious effect of stress raisers or notches on the resistance to fatigue of machine components, and other parts subjected to repeated dynamic loading, has been well known for many years. Most engineers in the mechanical field have, at one time or another, encountered a shaft which fractured due to a poor transition fillet, a holding-down bolt which failed due to insufficient tightening or inferior thread form, or a fitted member which broke through a combination of fretting corrosion and clamping stresses. All of these are examples of the damaging influence exerted by stress raisers in fatigue. Other common forms of stress raiser which have taken their toll of dynamic components are: keyways, oil holes, splines, quenching oil grinding cracks, tool marks, and sharp changes in section; some are the result of the design, others of poor execution of the design. It is our experience in the Mines Branch1 and I feel sure this will be corroborated by other fatigue investigators, that the majority of failures are due to incorrect design or faulty preparation of the part concerned, rather than to the use of inferior material. Quite frequently, it is true that the operating conditions necessitate the presence of a 'notch', but even in such cases methods are generally available by which its adverse effect on the life of the component can be reduced or annulled. The purpose of this paper is to discuss a few typical stress raisers, and to provide information on various processes for mitigating their effects in fatigue.

Jan 1, 1951

By R. E. Legg

This paper gives a brief outline of the mining and milling methods which will be used on the Stirling zinc-lead-copper ores by Stirling Mines, Limited, who have for the past two years been developing the Stirling mine in Richmond county, Nova Scotia, and who will bring the mine into production in November, 1929. No attempt has been made to give the paper a detailed technical character, for the main reason chat, since base-metal mining is something new in Nova Scotia, it is felt that a general description would be preferable before this Society, whose membership is mainly made up of chose engaged in the coal mining and associated industries. Furthermore, as both mining and milling operations will be governed to a certain degree by the experience gained after production commences, there are many points which cannot be definitely stated now. GEOLOGY Before discussing the mining methods, it is desirable to present a general picture of the geology and occurrence of the ore-bodies. The surface rocks in the vicinity of the mine consist of rhyolites of .pre-Cambrian age. These volcanic flows outcrop in very few places, usually along' the beds of creeks or on the shores of the numerous small lakes. Consequently, a detailed geological map is not available. The exploration work carried out to date has revealed a sheared zone extending through the volcanic flows for a distance of over 1,000 feet. Along this zone, there has been a replacement of the rhyolites by a carbonate rock for widths varying from 50 to 230 feet, and it is in this carbonate formation chat the mineralization at a later date took place.

Jan 1, 1929

By Graham Walker

A new Code of Practice for the brake performance of off -highway vehicles was established in Alberta in 1976. Vehicles loaded to gross vehicle weight must be capable of stopping with mechanical brakes five times in quick succession on a grade of 10 per cent from a speed of 28 miles per hour. Comparative trials of various brake systems have been carried out and some combinations capable of meeting the Code are identified. Some problem areas in truck braking are reviewed and potential developments indicated.

Jan 1, 1977