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By Barry D. Simmons

"A well-defined approach is essential to ensure the long-term success of a regional exploration program. Teck's approach in eastern Canada is designed to fulfill corporate objectives while recognizing certain unique parameters for exploration in the area. The elements of this approach include clearly defined objectives, technical considerations and personnel policies, all of which are equally important. The goal is a significant discovery before the mid-l990s and the company is confident that this target will be achieved.IntroductionAs one of Canada's oldest continuously operating mining companies, Teck Corporation traces its roots to Kirkland Lake, Ontario, with the development of the Teck-Hughes gold mine in 1913, later supplemented by production from the Lamaque gold mine in Val d'Or, Quebec. Control of the company was acquired by Temagami Mining Company, part of the Keevil Mining Group, in 1959. Credited as one of the first discoveries made using airborne geophysics, the Keevil Group had recently found the small but very high-grade copper deposits at Temagami, Ontario. These developments in eastern Canada formed a foundation for remarkable growth and Teck's present status as one of Canada's most successful and respected mining companies.Teck currently operates successful mining ventures across Canada and has international exposure through its association with Cominco Ltd., M.I.M. Holdings Limited and Metallgesellschaft AG. Operations in eastern Canada, however, remain an important component of Teck's ongoing success. The David Bell and Williams mines at Hernlo, Ontario, are Canada's lowest cost and largest gold operations, respectively. The Niobec Mine at Chicoutimi, Quebec, is North America's only significant producer of niobium. Teck maintains a 45070 interest in Golden Knight Resources Inc., part owner of the successful gold mining operation in the Casa Berardi area of northwestern Quebec. As a significant shareholder in Aur Resources Inc. and as a part owner, Teck is participating in the development of the Louvicourt deposit, a major base metal discovery at Val d'Or, Quebec."

Jan 1, 1992

By John O. Galloway

"The year 1947 was a momentous one in the history of the petroleum industry in Canada. It was in that year that Imperial Oil Limited made its discovery at Leduc, the forerunner of other discoveries, large and small, and the spark wl1ich started a most intensive exploration and development programme there.If, to use boxing parlance, Leduc was the first blow of a one-two combination which left doubting Thomases groggy, then Redwater was the number two blow which achieved the knockout. The oil industry's exploration leaders did about-face without delay and the rush of oil operators of all classifications to western Canada began. It is still continuing, and the influx of capital which the operators have brought in and are bringing in has a bouyant effect upon the over-all economy. The boom is on, but it is a sound one, and it is difficult to conceive that it will have anything but the most beneficial effect on Canada, and particularly western Canada.The petroleum industry is an important segment of the general economy. Its activities call for tremendous amounts of capital; its employees are well paid; it is a large customer for a wide range of products of other industries; its commodities are essential to the citizens and the nation.The industry is carried on by highly aggressive and independent groups and individuals, of which a small minority are integrated while the majority are relatively small operators engaged in only one or two phases of the business. Competition is the rule and, since the nature of the business is mass production, the industry is faced from time to time with serious problems, many of which are peculiar to it."

Jan 1, 1950

By C. K. Baxter, A. Odeshi, M. Mohammadi, E. D. Cyr

"Metal additive manufacturing has been a revolutionary step in designing new complex shapes with faster and cleaner building capacity in comparison to subtractive manufacturing processes. The ability to print lightweight alloys such as aluminum has made metal 3D printing attractive to different industrial sector from aerospace to energy and bioengineering. Of particular interest in this study, are the mechanical and microstructural properties of AlSi10Mg-200°C alloys. In this project, samples were 3D-printed in horizontal direction using an EOS M290 machine by Direct Metal Laser Sintering (DMLS) technique. Uniaxial tensile tests and high strain-rate impact e tests were carried out to investigate the mechanical properties and to study the repeatability of the process. A constitutive model is developed to predict the results of the mechanical tests at varying strain rates to better understand the high strain-rate behaviour of these alloys. Using optical microscopy, features such as scan tracks and melt pools within the AlSi10Mg-200°C samples were observed, and the microstructure was observed to be homogenous. The previously listed tests were compared to the results obtained for similar cast alloy counterpart, i.e. A360.0.INTRODUCTION A relatively new way of manufacturing parts is on the increase as rapid prototyping becomes increasingly popular throughout the world. Additive manufacturing is a process which, given a 3D model, uses metallic material in powder form to build a part layer by layer until completion (Gu, Meiners, Wissenbach, & Poprawe, 2013). This way of rapid prototyping is very attractive in comparison to other possibilities because of its ability to accommodate complex design and geometries. Conventional manufacturing methods have limitations when it comes to complex geometries, but additive manufacturing allows for increased design flexibilities while maintaining a light and stable final product (Murr et al., 2012). It also allows for a reasonable cost, especially for small batch sizes that would otherwise be extremely expensive."

Jan 1, 2018

By T. H. Peters

The historical development of this program, dating from the construction of Nickel Park at Copper Cliff in 1917 to the various current projects carried out in the Ontario Division's program, is reviewed. Practices used to grow vegetation on stressed areas, the beneficial aspect of the improved aesthetic appearance of company properties from the point of view of public relations and the improved approach to the workplace by the employee are discussed. The revegetation of the tailings area and its gradual transformation into a Wildlife Management Area is reviewed.

Jan 1, 1978

By G. A. Highcock

"Operations started at BCL in December 1973J and the smelter is currently in the seventh year of its fifth campaign. The next major shutdown is scheduled for 1995. During the current campaign, a number of major on-line refurbishments have been carried out without any significant disruption to production. These include the complete rebuild of both drying plant electrostatic precipitators, the installation of a new electrostatic precipitator at the flash furnace, the conversion to a distributed control system throughout the smelter, and the installation of a converter air blowing control system.IntroductionBCL Limited operates a nickel-copper mine in northeastern Botswana approximately 100 km southwest of Francistown. Surface operations for the production of high-grade nickel-copper matte at a design capacity of 42 000 metric tonnes per annum, were commissioned in December 1973. Detailed descriptions of the mine and surface facilities have been presented previously(1-3).Over the years, a number of major engineering modifications and metallurgical projects have been carried out to overcome operating difficulties. improve metal recoveries, increase production rates and provide a better working environment.One of the major results of these projects was an increase in the 19805 in flash furnace feed capacity from 70 t/h to 120 t/h of new concentrate with a nominal feed rate of 105 t/h being achieved.(4)Because of the ore characteristics, i.e. a high mass fraction of ore reporting to concentrate, BCL operates one of the highest capacity spray drying plants and flash smelting furnaces in the world(5).A schematic of the BCL smelter is shown in Figure 1. The smelter is now in the seventh year of its fifth campaign, with the next shutdown scheduled for mid-l99S. In this campaign, the following major projects were completed:"

Jan 1, 1995

By Christopher Andreae

Years before iron and steel works were established at Sydney, several thriving although short-lived iron works operated in Nova Scotia. These furnaces reflected the general nineteenth-century North American experience with iron works. At the beginning of the century, small furnaces struggled to supply local needs. Charcoal was the principal fuel and water powered most furnace equipment. By the end of the century, a few huge primary iron and steel works dominated production for Nova Scotia and the rest of Canada. Two sites achieved prominence in the nineteenthcentury Nova Scotia iron industry: Londonderry and Ferrona (Fig. 1). Londonderry, the larger and longerlasting of the two sites, is today a small village on the south flank of the Cobequid Mountains, about 30 km west of Truro. Prior to the establishment of an iron works in 1849, no community existed. At the peak of operation in the 1880s, however, over 2600 people were located there. The second site, Ferrona, today is a mere crossroads on the map, about 10 km south of New Glasgow. Following the construction of a blast furnace there in 1892, a small village grew up around the furnace. But once the furnace was blown out in 1904, the population gradually drifted away.

Jan 1, 1999

By K. Chomyn, R. Veenstra, P. Zangeneh, Hatch Ltd., C. Van der Woude, H. Ghorbani

"The furnace is the heart of smelting operations, and therefore the performance, reliability, and campaign life of the furnace are critical considerations. Furnace refractory is exposed to high temperatures and other harsh operating conditions causing brick erosion, crushing, and cracking, typically limiting the furnace campaign life and requiring costly furnace shut-downs for refractory re-lining. Despite extensive study, the in-service thermal / mechanical stresses in these complex refractory systems are not generally well understood. Hatch has developed a thermal-mechanical finite element analysis (FEA) based furnace refractory modeling approach that allows for the quantification of refractory movements, load distribution, and thermal / mechanical stresses.Due to the complexity of the refractory system, a range of models are used to identify and assess damage mechanisms and design improvements, including: 2D models, to capture expansion and movement of individual bricks, changes to load paths, and thermal stresses; and 3D models, to include the effect of differential expansion between bricks in each course, and assess overall load distributions. The 2D and 3D analyses include the effect of nonlinear temperature-dependent properties, thermal expansion, movement of individual bricks with frictional contacts (i.e., gaps can open, bricks can slide), and brick tensile or compressive failure. Both as-built and damaged conditions can be investigated (e.g., after bath zone brick erosion), for circular and rectangular furnaces. 3D models also include papering and brick joint & interface action.Analyses using these models have shown the importance of thermal stresses, papering, and geometry / arrangement of individual bricks. Results have been used to identify and assess damage mechanisms, showing good alignment with furnace autopsy observations. By using this FEA-based approach to quantify the refractory design, the risk of damage can be significantly reduced, low-cost design changes can be identified, and the furnace campaign life can be extended.INTRODUCTIONThe furnace is the heart of smelting operations and therefore the performance, reliability, and campaign life of the furnace are critical to the success of the smelting operation. Furnaces are inherently exposed to high temperatures, often in excess of 1600°C (Holappa, 2004), and furnace operating power has progressively increased over time (Voermann, Gerritsen, Candy, Stober, & Matyas, 2004). The refractory system must withstand high temperature, high heat flux, and other harsh operating conditions. These conditions are particularly significant for the furnace hearth, and can lead to damage including brick erosion due to molten material flows, crushing due to thermal expansion loads, and cracking due to severe thermal gradients within the bricks. Refractory damage typically limits the furnace campaign life, requiring costly furnace shut-downs for refractory re-lining (repair or replacement). In some cases the refractory may lose integrity causing damage to nearby equipment and harm to personnel."

Jan 1, 2016

By S. Harshaw, C. Doyle, A. E. M. Warner, D. Stremlaw

"In the Utility Nickel furnaces, the hearth and sidewalls are lined with high-Al2O3 bricks. During charging and thermal cycling (more so as the linings on these reverberatory furnaces age), pieces of brick spall or abrade from the refractory and collect on the top of the bath. These pieces are removed using a non-corrosive slag toward the end of the heat when the bath temperature is ~1600°C.This benign liquid can be generated by two methods. First and most obvious, suitable ingredients can be pre-mixed so that the flux (flux A) is isochemical with the non-corrosive slag. All that is needed to produce this targetted slag is heat. Second, in other proportions (flux B), the pre-mixed ingredients generate a corrosive slag that melts completely at -1200 °C and corrodes some but not all of the brick particles on the bath surface. As the reaction progresses, the slag changes composition eventually attaining the targetted benign composition. Using this option, additions are monitored to avoid overfluxing. In both cases, the generated slag/brick mixture can then be rabbled from the furnace. This practice has been successfully used for over two years and has been a factor in extending Utility Nickel furnace life to its current levels (about25% increase)."

Jan 1, 1993

By D. Marcotte

The Rock Quality Designation (RQD) is a standard scalar measure of rock quality used in common rock mass classification systems (e.g. RMR, Q system). RQD is measured along diamond drill holes. RQD interpolation between holes is nontrivial. Despite the inherent limitations of drill hole data and the local complexities of structural geology, it is often the only information available for mining and major civil engineering projects. Therefore, maximizing the usefulness of this data is warranted. We derive a correction for directional effects that help reduce the bias and improve the accuracy of the estimations. The correction is derived with the aid of numerous simulations. It relies on simple information, the angle between the joint normals and the borehole axis (JO). A reference direction is identified as the borehole direction with smallest JO. A multiple linear regression model based on JO statistics in the various boreholes defines the correction model. The corrected RQD values are then interpolated. It is shown the method enables reducing the bias on RQD estimation by 50% and improves the accuracy of the estimates by 30%. The corrected RQD values show stronger spatial continuity than the raw values. The benefits of estimating the RQD indirectly by using joint frequency measures are also assessed.

May 1, 2003

By K. Scalise, M. Teixeira, K. C. Kocsis, J. Parrish

"This paper aims to introduce and discuss a newly developed algorithm, which can be uploaded on smart watches and other mobile devices to inform and protect underground personnel working in hot and humid environments. Using this algorithm, the metabolic rate (M) of a worker can be determined in “real-time”. In addition, besides warning signs and alarm signals emitted by the smart watch, the algorithm has the ability to determine work-rest time periods based on the worker’s physiological parameters (e.g. age, height, weight, gender) and the climatic parameters (Td, Tw, flow velocity). This paper also investigates whether a re-designed auxiliary ventilation system can provide appropriate work conditions in the production stopes. INTRODUCTION An underground environment with high temperature and humidity conditions generated from various heat and moisture sources can significantly affect the thermoregulation processes of the human body. This can lead to heat-related illnesses such as heat rash, heat cramps, heat exhaustion, and heat stroke. Heat stroke is a serious illness that carries a high risk of fatality, if the underground workers are not immediately treated and the climatic conditions are not corrected (McPherson, 1993). There are two methods used to control the climatic conditions in underground mines: (1) Using ventilation and cooling systems to reduce the thermal stress on the mine workers, and (2) Reducing the heat transferred to the ventilating air from major sources such as: strata, auto-compression, mining equipment, groundwater, blasting, etc. The heat from strata and auto-compression is transferred to the ventilating air at varying degrees, based on factors such as the virgin rock temperature (VRT), the thermal properties of the surrounding rock formations, and the surface air temperature. However, the use of mining equipment and blasting processes can be managed to reduce their contribution to the mines’ overall heat load. To provide appropriate work conditions, selecting the most suitable cooling method depends on the level of heat to be removed, the location of the problem areas, and economic constraints (Brake & Bates, 2002; McPherson, 1993). Because every mine is unique, it is essential to monitor the climatic conditions to select the most appropriate method of cooling. A majority of the time, simply adjusting or re-designing the auxiliary ventilation system can efficiently remove the heat and dilute the contaminants. This may involve moving the ducting system, changing the size of the duct, changing the size of the auxiliary fan, or switching from forcing to an exhausting fan arrangement. If the required air volumes are higher than the existing primary ventilation system can supply, other measures may need to be taken to increase the airflow delivery. This may include regulating the flow in some areas of the mine to increase airflow to the desired area, adding booster fans, or replacing the primary fans."

Jan 1, 2019

By W. Grell

"In this paper, two methods of standardizing mill language are proposed; one is based on metric units and the other on English units. Tentative procedures for chemical and screen analysis based on published methods are proposed.Standard procedures for determining work index, and for leaching, flotation, and classification tests are outlined.Objects of Standardization:(1) to improve communication -(a) among gold metallurgists(b) with other branches of mineral dressing(c) with mineral dressing in other countries(d) with general scientific procedure(2) to improve mill control by -(a) standard methods of analysis (i)(ii)(iii)(b) standard methods of calcula tiort(c) standard accounting proceduresin the plantin the mill laboratoryin the assay office(3) to improve mill test work and investigationAreas of Standardization(1) Nomenclature or terminology(2) Measuring techniques(3) Test procedures(4) Accounting procedures"

Jan 1, 1966

By John I. Sharpe

Masses of pyritic copper and zinc ores are entrapped along the contact zone between two volcanic groups in the Matagami area. The upper limits of the sulphide concentrations tend to form concordant contacts against lava or cherty tuffite units of the younger group; the lower extremities tend to either follow transverse structures or merge with zones of dispersed sulphides. The sulphides are deformed and intruded by folded dykes. Close relations between metallization boundaries and volcanic lithology and stratigraphy, and a preliminary investigation of the fabrics and crystallization temperatures of the sulphide masses, suggest that the copper and zinc (but; not necessarily all the iron sulphides) were emplaced at h1gh temperatures during volcanism in near-surface lithological-stratigraphic traps. Introduction T HE Matagami area is centered 120 miles north of the Val d'Or and Noranda camps in north-western Quebec. For the present purpose, it is considered to comprise a 155-square-mile area in Isle-Dieu, Galinee and Daniel townships which encompasses the main sulphide masses. Airborne geophysical surveys within this area in 1956 led to the discovery of a large sulphide body -the.

Jan 1, 1965

By O. S. Perry, G. H. Charlewood, K. Griffin, S Ogryzlo, H. Hopkins, G. MacIntosh

"The gold mines of Kirkland Lake are in Teck township, Timiskaming district, Ontario, latitude 48°9'N. and longitude 80°3'W., at an elevation of 1,038 feet above sea-level.There are seven contiguous producing mines in a length of 3;1/2 miles along the general east-west strike of the deposits. The seven mines are, in order from west to east, Macassa, Kirkland Lake, Teck-Hughes, Lake Shore, Wright-Hargreaves, Sylvanite, and Toburn.The first discovery of gold in the zone was made by W. H. Wright in 1911 on the east claim of the Wright-Hargreaves property, and the following year the Tough brothers and H. Oakes found gold in what is now the No. 1 vein_ at the Toburn. Production began at the Toburn in 1915, followed by Teck-Hughes in 1917, Lake Shore in 1918, Kirkland Lake Gold in 1919, Wright-Hargreaves in 1921, Sylvanite in 1927, and Macassa in 1933.To the end of 1946, 31,938,350 tons of ore had been milled at the Kirkland Lake mines, from which 16,132,700 oz. gold, having a value of $498,517,600, were recovered. The bullion varies from mine to mine between 800 and 900 fine, the average for all the mines being 853. The average fineness of the native gold is 941.The workings of some of the mines are more than 6,000 feet deep and sinking to depths below 7,000 feet is now in progress.GENERAL GEOLOGYThe regional structural geology of the area in which the mines of Kirkland Lake occur is described in a preceding paper in this volume by J. E. Thomson."

Jan 1, 1954

By James A. H. Church

This paper is in the nature of a protest against the dangerous propaganda afoot for the prevention of new mining undertakings and which is based on the imaginary 'blue ruin' conditions supposed to exist in the industry. An article by Mr. G. R. Pratt, A.M.E.I.C. in the first issue of the Western Canada News, February 2nd, 1925, and entitled "Review of Coal Mining in Alberta", is an excellent example of this type of propaganda. The article is a tissue of misstatements, faulty deductions and erroneous conclusions. For instance it contains the statement that some coal measures in Alberta are mined at great depth - whereas we all know that there is no coal mined at great depth anywhere in the province; another error is the classification of all mines under one head irrespective of whether they are mining prospects, 'country banks', or pukka mines equipped with railway facilities; and I believe that suppressio veri is tantamount to suggestio falsi. The bulk of his article hinges on a Table 1, which shows the details of coal produced in Alberta during 1923. Studying this table Mr. Pratt, in the manner of a conjurer producing rabbits from a hat, offers the following for the confusion of the public:- (1) "Waste effort, want of capital, waste of coal resources which result from unrestricted development"; the fact being that the waste is due to the failure of the Department of the Interior to exercise the powers which are inherent in the form of lease.

Jan 1, 1925

By P. Hubert, J. P. Ildefonse, F. Qafssaoui, J. Poirier

Corrosion tests by corrosive alumina-lime slags were carried out on commercial high alumina bricks used in steel ladle linings and model refractories (with different raw materials : bauxite, andalusite, and different microstructures). Using (SEM) scanning electron microscope and (EDS) energy dispersive spectroscopy, microstructures of slag-corroded refractory interfaces were studied in detail. The monomineral and glassy phases, the composition of reaction products and chemical profiles were determined. A thermochemical analysis based on phase equilibrium diagrams has permitted to estimate the proportion and the composition of the high temperature intergranular liquid phase. These data were compared to the experimental microanalysis results. The viscosity of the high temperature liquids were calculated according to Urbain 's model and the relationship between the viscosity and the penetration of liquid phases were discussed. These theorical and experimental results were used to understand the complex phenomena of slag penetration and corrosion of andalusite and bauxite refractories at high temperature and to propose new ways of improvements for the formulation of high alumina refractories.

Jan 1, 2004

By Mei-Yan Yang, Ltd. Yunnan Yuntong Zinc Co., Yong-Xiang Li, Xing-Zheng Dai, Hong-Liang Wang, Meng-Yang Huang, Peng Zeng, Guo-Feng Li

"The removal of iron asgoethite from the high iron bearing solutions generated in zinc hydrometallurgy using a strong airflow device was investigated. The influence of oxygen flow, copper ion concentration, temperature and reaction time on iron precipitation as goethite was studied. The optimum conditions were: oxygen flow 0.2-0.35m3/h, copper ion concentration 0.25-0.5g/L, temperature 80-90oC, zinc oxide powder neutralizing agent and a reaction time of5to 7hours. Under the optimal conditions, the Fe2+concentration was reduced to 0.025g/L after iron precipitation, and the goethite residue contained 38.7wt.%Fe. The SEM and XRD analyses showed that the iron was present as well formed FeOOH crystals in the iron residue, and the amount of iron sulphate was very low. Production practice shows that, when the average iron concentration in the feed solution was 11.61g/L and 4.08g/L after precipitation, the weight of iron removed was 1,439kg/day. When the average iron concentration in the feed solution was 14.51g/L and 2.73g/L after precipitation, the weight of iron removed was 2,454kg/day. This represents a ~70 percent increase in iron removal.INTRODUCTIONThe objective of iron removal is to produce a small volume of iron residue, and our industrial goethite process meets this requirement. The high Fe(II) solution in our reactor isoxidized/hydrolyzed to precipitate goethite and the precipitate is sent to a pyro metallurgical furnace for final residue treatment. Some literature discusses (DengYong-guiet al., 2008;Meiguang-guiet al., 2001;Zhongzhu-qianet al., 1980) research on iron hydrolysis; one of the reported rate limiting parameters was the low availability of the oxidant when using air and another was the inhomogeneous air distribution. There are two iron hydrolysis-goethite precipitation methods; the Electrolytic Zinc process (EZ) and the Vieille Montagne process (VM) (Lei Xiang, 2006; Xuguo-qiang, 2007;ZhaoYonget al.,2005). The EZ method hydrolyzes the Fe3+directly to FeOOH. The weakness of the EZ process is the low recovery rate of the associated minor metals. The VM method reduces the iron to the ferrous state and then oxidizes the Fe(II)to Fe(III),with simultaneous hydrolysis/precipitation of the Fe(III) as FeOOH. Before iron hydrolysis, the minor metals, such as indium, could be selectively precipitated, because Fe(II)requires a high pH for hydrolysis. So the VM method has a high recovery rate for the minor metals. There levant goethite precipitation reaction is:"

Jan 1, 2016

By David G. Dixon, Ahmad Ghahremaninezhad, Edouard Asselin

"Atmospheric leaching of chalcopyrite in sulfuric acid solutions is a slow process due to the mineral’s passivation. We have investigated the nature of the passive film in this work. Electrochemical reduction and oxidation of chalcopyrite over the potential range of -0.5 to 1.2 VSHE were investigated in 0.5 M sulfuric acid solution (pH 0.3) at 25 ºC by multicyclic voltammetry and open circuit potential measurement. The influence of scan limits on the evolution of current peaks was studied with both stationary and rotating electrodes. It was observed that the anodic oxidation of chalcopyrite begins at potentials above 0.6 VSHE, most likely by preferential dissolution of iron atoms over copper atoms. The selective electro-dissolution process results in formation of a metal-deficient sulfide passive film (i.e. Cu1- xFe1-yS2, y > x). The passive film dissolves at 0.9 VSHE. Elemental sulfur is one of the products of chalcopyrite dissolution above 1.0 VSHE. Cathodic reactions within the potential region of 0.1 to 0.6 VSHE and anodic reactions at potentials lower that 0.5 VSHE are associated with at least one soluble species from solution. The soluble species involved in the cathodic reactions are likely ferric and cupric, while the soluble species involved in the anodic reactions is likely H2Saq."

Jan 1, 2014

By M. Mirnezami, J. A. Finch

The McGill component of the consortium contributed detailed examination of the electrokinetic properties of the constituent minerals, primarily pentlandite and serpentine. Mineral specimens were derived from an ore sample; mineralogical examination showed the serpentine was predominantly clinochrysotile, a fibrous mineral responsible for much of the flotation separation problem. The study included design of a novel sedimentation potential measuring device to classify the surface charge of the ore and electrophoresis measurements on single and mixed minerals which progressively approached flotation conditions. The sedimentation potential measurements provided a general association between surface charge and the visual state of aggregation as a function of pH. The electrophoresis experiments started with single minerals in a background of indifferent electrolyte and progressed to mixed minerals in a background of supernatant derived from an ore sample. The single mineral tests supported the suspected electrostatic interaction, i.e., hetero-coagulation, at flotation pH 9-10. The mixed mineral tests demonstrated this interaction and also revealed hetero-coagulation with Mg(OH)2 precipitates, derived from the supernatant. This interpretation was confirmed by optical and electron beam imaging. A series of agents, CMC, polyphosphate, soda ash, EDTA, were examined to disperse the system. To accommodate the small mass of single mineral available a novel turbidity measurement using a UV/Vis spectrophotometer was introduced. Selected conditions were used in contact angle and small-scale flotation tests.

Jan 1, 2011

By V. Taylor

"THE petroleum industry in Canada has been experiencing considerable difficulty in filling its manpower requirements during the last few years, and because of the rapidly expanding nature of the industry it is concerned about the supply that will be available to fill the needs of the future. As the oil industry is one of the more technically oriented industries, the most acute problem exists primarily in the field of profession-al/technical personnel. This is particularly true in the production and exploration side of the business, because it employs the highest percentage of this type of personnel. Let me illustrate this by giving you some figures reported by the Alberta Bureau of Statistics as of December, 1965 -out of a total of 9,641 male employees engaged in oil producing and geological and geophysical operations in Alberta, 3,021, or 31 per cent, were classified as engineers, geologists, geophysicists, managers and other professional personnel. No figures are available for 1946 to make a direct comparison of the expansion of the industry over the past twenty 466 years, but it is doubtful whether more than 100 professional/technical people were engaged in producing in Alberta at that time"

Jan 1, 1967

By A. K. Debnath

Coal is the mainstay of Indian energy supplies. The many-fold increase in demand for coal puts a huge pressure on augmenting production, primarily from opencast mines. The increase in production necessitates heavy blasting in overburden and coal benches of opencast mines, which poses numerous challenges in carrying out blasting operations techno-economically. Presently, the consumption of industrial explosives and accessories in Coal India Limited (CIL) has touched a whopping figure of $350 million USD per annum and CIL will be spending approximately $1 billion USD between 2012?2013 to 2014?2015 for procuring explosives and accessories. This paper discusses some of key challenges faced in various mines of CIL during blasting, where blast instrumentation at the mine level will prove to a harbinger for practicing blasting engineers. Presently, the problem of scattering in surface detonators and down-the-hole detonators affects the blast performance significantly by increased blast induced ground vibration and reduced fragmentation. The paper discusses a case study carried out at Umrer opencast project of CIL to investigate the effect of scattering by using blast simulation techniques (i.e., JKSimblast) and observing the actual blast results with the help of a high-speed camera and multi-channel high frequency data acquisition systems. The fragmentation assessment was carried out by adopting Digital Image Analysis techniques and using the granularity software viz. Wipfrag. The blast instrumentation in the case study mine resulted in improvement in fragmentation of 12.76% and a direct savings in explosives cost of 28%. Geophysical techniques such as the seismic survey method have been used at Umrer Project, CIL to characterize the rock mass using the Multi Channel Analysis of Surface Waves system for selecting the explosives technoeconomically. The minimum deck thickness for mines of CIL using drill cuttings as decking materials should be 10 D, where D is the drill diameter. The estimation of blast performance on the basis of prescribed Powder Factor (i.e., kg of explosives per m3 of rock) is technically unscientific as the criterion of a good blast depends on many factors (i.e., good heave, loose muck, muck profile angle, ease of digging, uniform fragmentation). The present paper proposes a new methodology for techno-economic evaluation of blast performance. The new methodology involves four significant factors viz. specific energy consumed by the loading equipment, charge factor, productive yield and diggability index for assessing blast performance. The use of user-friendly, accurate, reliable, rugged and handy instruments in blasting will significantly improve mine productivity, equipment efficiency and economics. The improvement in blast performance, even by 1%, will provide a significant savings of $3.5 million USD per annum to CIL. It may be concluded with high degree of confidence that blast instrumentation at the mine level will influence the mine productivity and economics.

Aug 1, 2013