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By Pierre Bernard

Contents of the presentation ? Overview of Brunswick 12 Mine ? Brief description of the mine geology ? Summary of the current Mineral Reserves and Additional Mineral Resources ? Review of the ongoing mining remnants evaluation process, particularly emphasizing the integrated work between the mine geologists, the mine engineers and the metallurgists ? Challenges and opportunities to extend the mine life

Apr 1, 2005

By Jean-Luc Collins

"This new tool can be used as a quick guide f or the assessment of the potential economic wealth of any risky capital project. It does provide an unambiguous recommendation of the type ""go or no go"" to the decision-maker simply by comparing two different ratios profit/investment. One ratio determines the minimum value required to at least break even while the other measures a probable value based on the asymptotic theory of statistical extremes.Its application is briefly illustrated by means of an underground gold mine extension project, an oil sands mine project and a polymetallic open pit project.Once a favourable recommendation has been obtained then a detailed ""cash flow after taxes"" analysis can be carried out for the project.IntroductionMany tools are used in financial decision-making such as the payback period, the discounted cash flow, the internal rate of return and the wealth growth rate (Berry , 1971).These tools are useful and meaningful in evaluating normal projects closely related to regular business where the number of assumptions made is usually very small and where the cost of capita! is usually selected as a discount rate or a hurdle value. In situations where a significant number of assumptions have to be made,two problems can emerge, namely:I. the risk involved is underestimated leading to a potential financial disaster; or2. a good opportunity is lost because the approach used in evaluating the project is too conservative.Each assumption has its own degree of uncertainty and it is well known that combining uncertainties together can lead to a total uncertainty of critical proportion. The easiest way to account for risk is to increase the discount rate or the hurdle value, but this approach alone is quite subjective and can easily lead to the problems described above."

Jan 1, 1993

By Bertrand Robinson

Great advances have been made in rubber-lined pumps for the pumping of mill pulps. The Canadian Allis Chalmers alone report ov.er 300 such pumps put into service during the past four years. Pumps in which both the casing and the impeller are rubber covered have proved most economical in handling the usual run of mill pulps, effecting large savings in power, maintenance, and shutdown costs. For the handling of pulps containing comparatively large, sharper edged /articles, rubber-lined casings with hard iron impellers have been developed by the pumping departments of Hollinger and Noranda. These rubber-iron combination pumps show an appreciable reduction in overall pumping costs as compared with the all-rubber and the all-iron pumps. The power efficiency is lower in rubber-iron than in all-rubber pumps but higher than in the all-iron pumps, with lower replacement costs due to the cheap iron impellers used. Where continuous operation is essential, however, and duplication of units to take care of shutdown time for replacement of parts is not within the expenditure budget of the company, all-rubber pumps are being used t0 a greater extent. As in all items pertaining to milling operations, the economics of the situation must be studied as closely as the technical details, to arrive at the most advisable practice.

Jan 1, 1939

By E. O. Lilge

THE USE of the Driessen cone as a heavy-media concentrator involves a mineral dressing process in which many variables inherent in the ore and in the process may have an effect on the efficiency of mineral separation and the operation of the cone. The magnitude of these effects and their possible interrelationships must be known before a full-scale plant can be designed and built. It appears that, among the most important variables, are the following: Ore Variables: The particle size of feed The difference in specific gravity between economic and non-economic minerals The intimacy of mineral association Cone Variables: Cone inlet area Ore to media ratio Cone ratio Size distribution in heavy media Specific gravity of media Viscosity of media Type of media

Jan 1, 1956

By B. S. Ignasiak, B. N. Nandi, D. S. Montgomery

The growing need to measure the extent of weathering of coking coal in storage and in transit prompted the comparison of the dilatation of coking coal on heating, which is known to be a sensitive index of oxidation, with the composition and volume of the gases produced by a mild pyrolysis of the same coal. It was found that the pyrolysis method had the advantage in that it could be used to study coking coals in advanced stages of oxidation, when the swelling properties had been largely destroyed. Of the various constituents in the pyrolysis gas, the most sensitive indication of coal oxidation was the volume of carbon monoxide evolved per gram of coal. For the coals examined, this index appeared to be at its best when the temperature of pyrolysis was approximately 35oC.

Jan 1, 1970

By F Kelly

"A central composite experimental design was used to determine empirical relationships between the operating variables of a ball mill and the characteristics of the ground products. The independent variables selected for the study were the work index and size distribution of the feed material, the feed rate and the pulp density. The measured responses included product size distribution, product surface area, viscosity of pulp discharge, weight of dry solids in mill, mill time constant and emitted sonic vibrations. The ball mill was operated continuously in open circuit during each experimental run.Multivariable regression techniques were used to derive linear empirical models from the experimental results. Of the four factors studied, the grindability of the feed material significantly affected every measured response. The size distribution of the ground product was affected significantly by the feed rate and the size distribution of the feed, but not by the pulp• density. Feed throughput capacity and pulp density were significant to the viscosity of the pulp discharge, the weight of solids in the mill and the mill time constant. Significant first-and second-order models are given for the above relationships. The relation-ships between the characteristics of the sonic vibrations of the operating mill and the various dependent variables have not as yet been established."

Jan 1, 1970

By Karl J. C. Harries

"1.1. WHAT ARE AGREEMENTS AND HOW ARE THEY FORMED?In order to have an agreement, at common law, there must be an offer, acceptance of that offer, and consideration passing between the parties. In addition, the material terms (i.e. the basics or substance) of the agreement must be discernible, preferably by means of documentation. Although these concepts may appear simple and straightforward, the law relating to them is voluminous and complex. Some brief comments are worthwhile.• Offer/acceptance: Both offer and acceptance should be in writing, but they need not be. The actions, conversations, and/or correspondence of the parties may constitute either or both of them. Notwithstanding, the local law or practice of a jurisdiction will impose some specific requirements for certain types of agreements. If these requirements are not met, the agreement may be unenforceable. For example, Ontario’s Mining Act requires transfers of unpatented mining claims to be evidenced in writing and recorded.1• Consideration: Consideration is usually thought of as being money, but it can be virtually anything, even “the premises” (i.e. the mutual covenants or promises contained in the agreement itself). In addition, if one party, relying upon the offer of another, does something to his detriment, then the doing of the act can be considered to be an acceptance of the offer and, under the legal concept of “detrimental reliance”, can also be consideration. Whether or not detrimental reliance exists will depend upon the circumstances of each case.2• Material terms: The requirement that the material terms of an agreement must be discernible does not mean that all of the terms of an agreement must be documented or even have been considered, just the basic or material ones. In addition, it will be up to a judge to decide what is material – not necessarily the parties. In order to establish the material terms, a Court may look at all relevant documentation and may hear oral evidence. It will resist “writing the agreement”"

Jan 1, 2003

By D. Komljenovic, E. Lafontaine, J. Paraszczak

Availability of the production equipment used in underground mines has a substantial impact on production costs and, thus, on mine profitability. Appropriate collection of pertinent data and information, as well as use of adequate performance measures and their analyses, can help mine operators identify cost-effective opportunities to improve equipment availability. This paper presents study results aimed at reviewing and analyzing means and measures used to quantify equipment availability and its contributing factors (reliability, maintainability and maintenance support) in several Canadian underground mines. It overviews sources, as well as quality and quantity of relevant data and information, and examines performance measures and their definitions, as applied to surveyed mines. Problems concerning data acquisition and meaningfulness of the performance measures are discussed. The paper concludes with some suggestions and recommendations concerning several aspects of equipment availability assessment. Evidence suggests that the latter may become a more useful tool for mine operators in their efforts to reduce production cost.

Jan 1, 2008

By David Scott, Denis V. Lachance, Daniel Marcotie

"LocationThe Heath Steele mine is located 50 km northwest of Miramichi, New Brunswick.Brief DescriptionHeath Steele is a 2700 t/d, copper-lead-zinc operation which employs conventional crushing, grinding, and differential flotation.HistoryThe Heath Steele mine is located in northeastern New Brunswick approximately 50 km northwest of the city of Miramichi and 65 km southwest of Bathurst. The massive sulphides containing ore values in zinc, lead, copper and silver were discovered in 1953 as a result of a joint venture between the American Metal Company and the International Nickel Company of Canada. The discovery was named after Mr. Heath Steele, manager of exploration for Amco at the time of the discovery.Mill production began in February 1957; however, the mine was forced to shutdown in 1958 due to depressed metal prices and metallurgical problems. It was re-opened in 1962 and milling operations resumed at 725 t/d until 1968 when the milling capacity was boosted to 1450 t/d and then to 2700 t/d in 1969.OreThe main ore zones are massive sulphides with very fine mineral grain. The chalcopyrite, galena and marmatitesphalerite occurrences are finely disseminated.Liberation is accomplished by grinding to 68% to 72% <400 mesh. Average mill feed assays are 0.8% to 1.2% copper, 1.8% to 2.5% lead, and 5.5% to 6.5% zinc, with 60 to 75 g/t silver."

Jan 1, 2000

By M. Coleman, M. E. Reed

The control of feed delivery quality to the flash furnace remains an unsolved problem. Many operations around the world still have limited control of feed quality to their flash furnace. Schenck Process and WorleyParsons continue to work towards the ‘holy grail’ of simple quality feed delivering both radial feed distribution and pulseless feed delivery. Ten years ago they joined forces to offer a system based on then Clyde Process RotoFeed system which could deliver ground level installation, online mixing of materials, pulseless feeding direct to the burner, with good radial distribution. Unfortunately, this proved to be too large a step for the Flash Smelting community and met with resistance from the process owners. Since then the community has developed a range of options some of which have been implemented over this period. Despite these improvements there are still areas of concern including safety issues associated with concentrate leaks and spills, uncontrolled variations in feed rate including massive flooding events, intermittent distribution improvement and set up of the burner continues to be trial and error and hard to repeat the success in each burner campaign. These continue to impact flash furnace performance globally on a daily basis. Following the community reticence to pursue the complete solution a number of interim steps are now available to pave the way to the ultimate feed system. The mixing of material has been installed and is delivering line blended materials on a daily basis. This paper will investigate the developments over the last 10 years and discuss the pros and cons of this incremental step process for overall furnace control. INTRODUCTION Schenck Process and WorleyParsons have continued to interact and observe changes in the flash smelting industry and to consider application of the Clyde RotoFeed now incorporated in the Schenck Process ProStreamTM range for delivery of feed directly to the concentrate or matte burner. Schenck Process pneumatic injection from the Clyde Process range, ProStreamTM, utilises two types of volumetric feeders to accurately control the feed of material into an injection pipeline. These are referred to as the RotoFeed and RotoScrew technologies and the choice of feeder type is dependent on the characteristics of the material to be handled. The RotoFeed is generally used for finer, granular and powdered materials which cannot be accurately handled with a screw such as pulverised coal and copper concentrate, whilst the RotoScrew is particularly suited to coarser lump materials, particularly abrasive of cohesive materials like zinc powder, electronic scrap and metal ashes. Both units can operate at high pressures and many systems work at 3 to 10 bar with the occasional system working at 20 or 30bar for carbon to gasifiers. For the Flash furnace the ProStreamTM units can be used to deliver each of the furnace feed materials into a single line, mixing the materials homogeneously and live to the burner.

Jan 1, 2019

By Kretschmar. U. H.

Fieldwork in the Meguma of Nova Scotia and Archean equivalents shows that bedding-parallel quartz lode gold veins (LVs) commonly occur at the top of graded elastic sequences. We define a "gold cycle" (GC) by analogy with Bouma turbidites and show that most "shear zones" and "lamprophyres" correspond to the upper pelagic-pelitic (E) division. We describe GCs from Archean Chester Twp, ON; Elmhirst, ON; Bourlamaque, QC; "intrusions" and interpret them as crystal tuffs and tuff-breccias. Extensive early Archean pyroclastic volcanism is implied: the genesis of trondjhemite-tonalite-granodiorite (TTG) rocks must be re-examined. The geopetal nature and asymmetric alteration of LVs indicates genesis from sea-floor hydrothermal vents. Textures suggest that often quartz was deposited as a gel. Vent geometry (fracture, point source or diffuse seep), bottom topography and vent spacing is reflected in wade-thickness plots. GC facing directions survive metamorphism. The Bourlamaque batholith was a flat-lying sheet of quartz-feldspar-hornblende crystal tuff, and isoclinal folding has repeated one or more gold-bearing horizons. Syngenesis clarifies and simplifies LV formation with major implications for models. Exploration becomes more cost-effective. Basin analysis, whole rock geochemistry, ore lens geometry and vent spacing can be used.

Jan 1, 2011

By Q. Han

A modified cast-on method has been developed to reinforce aluminum castings with steel insert. Defect-free bond between the steel insert and the aluminum casting has been consistently obtained. Data obtained from a push-out experiment indicated that the bond strength was much higher than that obtained using the Al-Fin approach. This paper introduces this modified method in four sections: the coating of the steel pins, the cast-in method, microstructure characterization, and the bond strength. The section on the coating of the steel pins contains coating material selection, electro-plating technique for plating Cu and Ni on steel, and diffusion bonding of the coatings to the steel. The section on cast-in method deals with factors that affecting the quality of the metallurgical bond between the coated steel and the aluminum castings. The results of microstructure characteristics of the bonding are presented in the microstructure characterization section. A push-out experiment and the results obtained using this method is described in the section of bond strength/mechanical property.

Jan 1, 2015

By J. W. Gregg, P. M. Dranchuk, D. L. Flock

"From preliminary investigations it has been observed that although evaporation losses may be estimated by comparing single values of certain physical properties of crude oils and their evaporation residues, such techniques possess little accuracy unless both the evaporation process and the variation of the property as a function of the process are completely known. The accuracy of estimation may be increased somewhat through the comparison of property mid-per-cent curves. Further increases in accuracy are possible if bottoms yield •curves rather than mid-percent curves are used. The use of both the mid-percent and bottoms yield curves however involves a prohibitive amount of effort in most cases. Examinations of distillation bottoms from Hempel type distillations carried to end points just short of the cracking point have indicated that these bottoms are not appreciably affected by the evaporation process. It was further observed that bottoms of identical API gravity, obtained from a crude oil and its evaporation residues behave as if they were pure components which were unaffected by evaporation. Based on these observations Hempel distillation bottoms of equal API gravity were obtained for a crude oil and its various evaporation residues from API gravity bottoms yield curves. The volume percent of these bottoms in the crude oil and its residues were used to calculate the evaporation losses suffered by the crude in order to yield the various residues. The results indicate that, although further refinements in technique are required, it is possible to calculate evaporation losses with an accept-able degree of accuracy through the use of this method."

Jan 1, 1960

By W. S. Hargratt

THE present era of exploitation of the Little Long Lac and Sturgeon River areas commenced in 1925, when Beardmore Gold Mines started development of what is now the property of Northern Empire Mines. A shaft was sunk in 1927-28 and a very limited amount of underground work was carried out, following which the property was shut down. It remained idle until 1932, when Empire Star Mines, a Delaware Company, optioned the property. This Company formed the Northern Empire Mines Company, Limited, to operate the mine, and immediately instigated an aggressive programme of surface and underground development. By the summer of 1933, sufficient ore was indicated to justify the installation of a small mill. The decision was also reached to bring in electric power. A power-line was built from Hydro, the Ontario Power Commission&apos;s development on the Nipigon river, to the mine, a distance of approximately 50 miles. This work was entirely financed by Northern Empire Mines. Mill construction was commenced in October, 1933, and completed by March, 1934, thus making this mine the first producer in this district.

Jan 1, 1940

By S. Oppenheimer, P. Au, R. M. Kearsey, J. Tsang, E. McDevitt

A new superalloy, ATI 718Plus® Alloy (718Plus), has been developed to have a 55oC higher temperature capability over the traditionally used Alloy 718, while maintaining favourable processing characteristics and intrinsic raw material costs. The fatigue and dwell-fatigue behaviour of four microstructural variations of 718Plus are evaluated and compared to Waspaloy: 1) standard heat treated condition (HT1), 2) standard heat treated condition with thermal exposure at 732ºC (1350ºF) for 1000 hours (HT2), 3) fine grain condition with a modified d phase (HT3), and 4) fine grain overaged through modified heat treatment (HT4). The results show that the steady-state fatigue crack growth rates of each microstructural variation and both alloys are identical, with all of the 718Plus variations showing a clear advantage over Waspaloy in the fatigue crack threshold regime. Dwell-fatigue results show that Waspaloy has better resistance to crack propagation under dwell conditions; however, optimization of the precipitate phase shows vast improvement in the dwell-fatigue resistance of 718Plus.

Jan 1, 2010

1.Assessment of methane content in coal. Given a naturally low methane content in 11 Coal Seam and the fact that the areas of the 11 Seam adjacent to the tunnelway were degassing for a very, very long time due to previous development and mining, it is conservatively estimated that the remaining in -situ methane is less than 0.5m3/tonne. 2. Continuous miner cutting rate based on the past practice. The best loading rate recorded at the past operations of Smoky River Coal was 45 seconds for a 8 tonnes shuttle car. Using these records, the maximum peak loading rate potential at the face is calculated at 0.178 tonnes per one second or 10.67 tonnes per one minute. 3. Methane release at the face. ?The actual face methane liberation, conservatively assumed at 40% of the total in situ content: 0.20 m3/tonne ?The peak cutting rate: 0.178 t/sec ?The maximum (peak) face methane release: 0.20*0.178 = 0.036 m3/sec

May 1, 2003

By S. Kaiman

This paper describes flotation test work conducted over the past several years at the Mines Branch, Ottawa, on the radioactive quartz-pebble conglomerate ores of the Elliot Lake area of Ontario. The purpose of this work has been to produce a uranium flotation concentrate for sub-sequent leaching operations. The results of earlier investigations are summarized and correlated with the results of mineralogical studies of the ores and flotation products. The results of recent pilot-plant investigations by flotation, as well as by gravity concentration followed by flotation of the gravity tailings, are given. The principal collector used for uranium flotation was a tall oil fatty acid, and the indicated total cost of all reagents ranged from 21 to 31 cents per ton of ore treated.

Jan 1, 1966

By M. Tadayonsaidi

The effect of alloying elements on the mechanical properties and thermal expansion of 336 casting alloy usually used as piston alloy which has low thermal expansion and very good high-temperature mechanical properties and good wear resistance was investigated. The mechanical properties and thermal expansion characteristic of samples with different combination of alloying elements, which enhance to reduce the cost of products, have been studies, The results show remarkable increase in the mechanical properties with increasing the amount of Cu and Mg, while are reduced with increasing amount of Ni, On the other hand, the use of eutectic aluminum alloy as 336 alloy with higher percent of Cu and Mg and lower percent of Ni are recommended for industry, due to economical viewpoint and satisfactory properties.

Jan 1, 2005

By Norman Orr, J. W. Gregg, Jack Wahl

The Pembina Cardium pool is a low permeability, stratified, solution-gas drive reservoir. Water-flooding has proven to be an effective means of pressure maintenance for all areas of the pool in which an economic rate of water injection can be maintained. The majority of water injection wells in the pool are converted oil well~ with capacities greater than 100 millidarcy-feet. If the average injection rate per unit of capacity can be in-creased the lower capacity areas of the pool can be economically flooded. Theory, laboratory work, and two . early miscible-flooding projects with-in the pool suggested that average water injection rates for converted wells could be increased two to three-fold by the initial injection of natural gas liquids and natural gas. How-ever, these two early projects received volumes of natural gas liquid!:' and high-pressure natural gas which would be economically prohibitive for routine stimulation. Area D, one of the Five-

Jan 1, 1962

By A. D. Yell

"Recovery of water is always a major factor in the Beneficiation process. As Preparation Plants become larger the recovery of water for reuse, is a critical cost consideration. Tema Isenmann Inc in conjunction with our sister Company Multotec Manufacturing, has over the years, developed numerous different Screen Panels, Sieve Bends and Static Screens for dewatering. This paper will focus on a new innovation, the TeePee™ Panel which has double the open area of conventional Screen Panels. This results in efficient dewatering (reduced filter cake moistures) which allows for the use of smaller Vibrating Screens or increased capacity on existing Vibrating Screens. A major factor in the efficiency of any Screen Panel, including TeePee™ Panels, is the performance of the Vibrating Screen. If the Vibrating Screen does not have the required gravitational force or screen area to drain it will not dewater efficiently. Therefore a holistic approach has to be taken where the Vibrating Screen needs to operate at an optimal level, in conjunction with the correct Screen Panels, to achieve efficient dewatering. Key performance areas for Vibrating Screens are therefore detailed in this paper with an emphasis on important dewatering criteria. Case studies of different dewatering applications are included, where the use of TeePee™ Panels, has shown a marked improvement over conventional flat Screen Panels in reduction of filter cake moisture content.INTRODUCTION Dewatering can be done in a number of different ways and is largely dependent on the ore type, the particle size distribution and to what extent one needs to dewater will determine the method used. There are a number of different dewatering methods that can be used for particles above 200 micron, including Screen Bowl Centrifuges, Filter Presses, Static Screens, Static Sieve Bends and Vibrating Screens. This paper will focus primarily on Vibrating Dewatering Screens showing improved drainage and a reduction in the filter cake moisture content. KEY PERFORMANCE CRITERIAL FOR VIBRATING DEWATERING SCREENS For clarification the critical key performance criteria for Vibrating Dewatering Screens are set out in this paper. Dewatering Screens Vibrating Dewatering Screens are normally linear motion, either horizontal or inclined at 5 to 7° upwards with a vertical or back sloped plate at 45° to the rest of the screen deck. The back plate will often have screen panels in them to increase the dewatering capability, as shown in Figure 2 below."

Jan 1, 2017