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By Scott Hean

"Environment and the economy are interwoven irrevocably. They need to be publicly discussed, and discussed often so that new approaches can be understood and developed - approaches which are complimentary, not confrontational.Discussion on the environment is timely, from the perspective of mining engineers and developers, from that of bankers and from their shared perspective as people concerned with enhancing the quality of life, the environment and the economy.This paper will touch on how what is called the ""environmental economy "" that has evolved has become entangled with regulatory and financial issues in a way that is dangerous for all of us. It will also look at some of the promising possibilities that a world-wide and continuing concern for the environment holds out for us.For many decades, British Columbia has provided some of the key examples of the intertwining of environmental and economic issues, and, very importantly, providing the people prepared to do something about them.Canada's first environment minister, the late Jack Davis, came from British Columbia. He led this country's delegation to the Stockholm Environment Conference in 1972, a conference that laid the groundwork of principles necessary to establish some international certainty as to the legal liability for causing trans-national environmental damage.Another British Columbian who was also a national environment minister, John Fraser - now the Speaker of the House of Commons - was one of the first to dramatize the importance of acid rain and force it into the international public arena.Some 20 years ago, British Columbians made Vancouver and their province one of the major centres of opposition to the Alaska Pipeline and Tanker System - with some justification, it now seems.That a British Columbian , then MP David Anderson, was given legal recognition to sue in a United States' court against a system that was either in U.S. territory or international waters was an important precedent in, and of, itself in terms of environmental law. That old controversy is now a very current case study - in terms of dealing with the question of liability.-"

Jan 1, 1991

By Scott Beer

What New Technologies Will Drive Economic Improvements? ??Historical ?1060?s: Mainframe Technologies ?1970?s: Mini Computing ?1980?s: Workstation Computing ?1990?s: Personal Computing ?2000?s: Network Computing Internet PDAs Cellular phones ??What?s the next technology improvement? ??What?s next for Mining?

May 1, 2009

By D. Raicevic

After more than 93% of the uranium is extracted from Elliot Lake uranium ores by a sulphuric acid leaching process, the leach residue (tailings) contains small amounts of uranium and radioactive isotopes, particularly radium-226, which is the most serious health hazard. Heavy metal components and pyrite are also present, along with the gangue minerals. Currently, over /000 acres of the Elliot Lake area are covered with these tailings, which contain over five million tons of pyrite. Because of constant oxidation of the pyrite by bacteria (thiobacillus) and the presence of moisture, pyrite slowly generates sulphuric acid, which steadily leaches the metal-bearing constituents from the tailings. The seepage-flows of the dissolved contaminants, although often quite low in volume, have an environmental impact on the Elliot Lake area. Although these seepages are treated and most of the contaminants removed and impounded, a small amount of the radioactive contaminants reaches Lake Huron via the Serpent River. This paper describes a flotation approach for treatment of the Elliot Lake uranium tailings to produce new, decontaminated tailings practically free of pyrite, with radium, thorium and uranium contents considerably reduced. The decontaminated tailing produced, which comprises about 75% by weight of the current uranium tailings, appears to be suitable for mine backfill. Because mine backfilling normally uses about 50% of the plant tailings, the surface storage of about half of the uranium tailings, therefore, would be eliminated by this process. Mine backfilling would also increase the mine production and thus enlarge the over-all uranium resources due to recovery of the ore from pillars. The pyrite concentrate produced from the current uranium tailings would be suitable for sulphuric acid production. The possibility of uranium recovery, and disposal of radium and thorium from the concentrates produced, is now being studied at CANMET.

Jan 1, 1979

By W. Evans, C. E. Ells

Nuclear power reactors using zirconium alloy pressure tubes generate electricity in several countries. Such reactors are particularly important in Ontario, where CANDUs* generate about 30% of the total electricity produced in the Province. Starting with the commitment of NPD-2 in 1956, the pressure tubes of the first five CANDU reactors were made of coldworked Zircaloy-Z, an alloy of Zr and Sn. This alloy was developed by the US Navy, but the decision to use it in a cold-worked condition was based on AECL work. In 1958, the USSR published information on a new alloy, Zr-2.5 wt% Nb. The Nb promotes stabilization of the (3-phase in the material, thus presenting opportunities of exploiting metallurgically strong pressure tubes analogous to the heat-treatable cx-{3 titanium alloys. After construction of two reactors using Zr-2.5 wt% Nb in a quenched and aged condition, an extensive development program on cold-worked Zr-2.5 wt% Nb pressure tubes resulted in them becoming the reference tubes for all CANDU reactors committed since 1966. Anticipating the future needs of the domestic and export markets, AECL have pressure tubes of Zr-3.3 wt% Sn-0.8 wt% Nb-0.8 wt% Mo (Excel) in an advanced state of development. These tubes will be used in an annealed condition; our projections show that they will have improved dimensional stability over the lifetime of the reactors. These improvements result from experimental programs leading to an understanding of the relationship between microstructures and fabrication variables and effects of the environment during service in nuclear reactors.

Jan 1, 1981

By Peter N. Calder, Louise H. Michaud

"An interactive mine planning package has been developed to aid with the tasks involved in generating dragline mine plans. This package employs recent advances in PC-based,3D computer graphics and 3D geologic modelling. A Gridded Seam Model (GSM), capable of modelling rugged topography and multiple coal seams, including folding and faulting, is used to generate the geologic database This model is then integrated with an interactive graphics mine planning system in order to develop one model and one database for the generation of the mine design, the depletion of the coal reserves and the removal of waste material.As well as offering large potential saving in the time required to carry out the planning tasks, the system offers immediate visual feedback to the planning engineer. This can greatly aid in the conceptual understanding of complex geology and mine plans and can allow for the evaluation of a number of mining options within a reasonable time frame.IntroductionThere are a large number of variables that must be taken into account during the development of a dragline mine plan. This is especially true when developing a mine in mountainous terrain, where there is a lack of continuity of the geology and topography over the mine site. Until recently, the complexity of dragline mine plans has prohibited the development of a universal mine planning package that is applicable to all geologic and topographic situations. The majority of the commercial programs that are presently available to facilitate dragline mine planning have been developed for specific mine properties or are limited in the coal geology and mining methods that they can simulate (Brown and Clifford, 1983; White 1983; White and Jones, 1984; Sadri and Lee, 1982; Dagdelen, 1979)."

Jan 1, 1993

By C. Bernier

This paper deals with three major problems associated with mining operations during the winter. These are the maintenance of the cooling systems of diesel engines, the high incidence of hydraulic dump failures on packaging machines, and the build-up of frozen fines on wet-ore conveyor belts.

Jan 1, 1966

By Euler M. De Souza

"This paper presents a study developed to assess the potential use of salt tailings as backfill to control surface subsidence and as a mine bulkhead used to isolate areas of potential brine inflows. A series of index tests, centrifuge model tests and quasi-static creep consolidation tests were performed to evaluate the creep and consolidation properties of salt backfl1l and to evaluate the effect of brine inflow and brine infiltration on backfill behaviour. The centrifuge models were specifically designed to study the mechanical behaviour of salt backfill under the influence of brine inflow and long-term creep. Test results indicated that salt tailings could be applied underground as a bulkhead to seal off areas of potential inflow with the additional advantage of controlling room closure and local back instability. It is hoped that this study will assist mine planners to develop contingency plans to control brine inflow occurrences. IntroductionThe use of salt tailings as backfill is a technique that would assist in the control of potential brine inflows and surface subsidence, and would have a very positive impact on the long term adverse environmental effects associated with surface salt tailings disposal. A centrifuge testing program was designed to evaluate the behaviour of salt tailings as backfill; the effectiveness of salt backfill as a bulkhead used to isolate areas of potential brine inflow and the potential use of salt backfill to control surface subsidence. The testing program was also used to evaluate the creep-consolidation properties of salt backfill and to evaluate the effect of brine inflow and brine infiltration on backfill behaviour. This paper presents the results of the experimental centrifuge testing program and a comparison of results with models tested under I g using an electrohydraulic servo-controlled loading frame (MTS) and a creep consolidation cell. Applicability of the results to practical underground soft rock mining is also discussed.The centrifuge model tests indicated that salt tailings could be applied underground as bulkheads to seal off areas of potential inflow with the additional advantage of controlling room closure and local back instability. Because the applied stresses (1.2 MPa) and fill consolidation were relatively low, the centrifuge simulated bulkhead did not retain all of the inflow brine. At typical field stresses it is expected that the fill would be able to seal off panels with brine inflows. Further testing at higher stresses are suggested to determine the consolidation and stress levels at which the fill would completely retain any potential brine inflow head and positively act as mine bulkhead."

Jan 1, 1994

By Robert B. Parsons

"The pendulum in Ottawa has swung dramatically from fiscal policy to monetary policy over the last several years. International trends indicate that the pendulum has to start its swing the other way, if Canada's mining industry is to maintain its preeminent position in the global mining arena. This article, which is based on a paper presented by the author at the 37th Annual Meeting of the Newfoundland Branch of CIM, identifies these trends and how they could interact with Canadian policy.IntroductionThe title of this paper is not a very imaginative or catchy one, but it states the topic quite succinctly, if not tersely. This paper looks into a crystal ball to see what might be in store for mine financing over the balance of the current decade.In the event that the reader feels some trepidation about the prospect that such a paper could seek to be the definitive work on the subject, it should be made clear at the outset that this is not the case. The author is, after all, not an economist, a scholar, a financial analyst, or a soothsayer, but is rather a simple accountant who has been closely involved with the mining industry, and the financing thereof, for some twenty years.The paper recognizes that, while a mine may be born when production begins, the mine is conceived when exploration starts. As this act of conception is obviously an essential part of mining, the financing of exploration is also covered in this paper. To attain a focus, this paper approaches the topic of mine financing in the nineties as follows: first, the major emerging forces in the industry are identified: and, second, the implications of each of these forces on financing are considered."

Jan 1, 1991

By D. Laguitton, D. Cimon

"BILMAT is one of the most powerful algorithms in existence for material balance computation in mineral processing flowsheets. It is based on a hierarchical decomposition coupled with the Lagrange multipliers method widely reported in the literature. Flowrates can be calculated optionally for pulp, solid or water. Assays are adjusted for a variety of subnetworks, such as assays of the solid as well as assays of fractions of the solid called level 4 data (l: pulp, 2:solid and water, 3:assays of solid, 4:assays of classes of solid).BILMAT4 is a new implementation of BIU1AT that operates in a new microcomputer environment and makes the method more accessible than ever. Its main features are a full-screen colour editor allowing graphic flowsheet drawing and data entry with automatic error checking. Mass balance equations are automatically generated by analysis of the graphics and corresponding data, thus relieving users from the error-prone definition of networks. Sensitivity analysis is performed to assess confidence intervals of computed flowrates and adjusted assays.BILMAT4 incorporates an option for gold leaching circuits where the element to be balanced appears in both the solid and liquid phases with negligible effect on the mass flows of solids. Recoveries are computed in all streams. This program is currently released by CANMET as part of the CAMP collection for Computer Aided Mineral Processing. A complete sample run of the program is discussed."

Jan 1, 1989

By S. Harvey

The McArthur River deposit is a structurally-controlled unconformity-related uranium deposit. The mineralization is situated at the intersection of a pronounced fault zone, referred to as the P2 fault zone, and the unconformity between Paleoproterozoic Wollaston Group metasedimentary rock and Paleoproterozoic to Mesoproterozoic Athabasca Group. Mineralization is variably hosted within the Athabasca Group fault wedge and the faulted basement, consisting of twelve zones covering a strike length of 2,700 m. The main P2 fault zone consists of several reactivated foliation-parallel faults containing narrow seams of graphitic clay gouge that are separated by highly cleaved, graphitic wall rock. The mine grid east-dipping P2 fault zone is characterized by reverse offset of the unconformity surface. It varies from a single discrete fault to splay offsets consisting of two to three individual splays. The combined vertical offset along the P2 fault zone is a maximum of about 80 m. The fault has emplaced a wedge-shaped sequence of Wollaston Group metasedimentary rocks into the Athabasca Group. Foliation-oblique faults occur throughout the McArthur deposit trend. Steep east-northeast trending faults generally exhibit apparent oblique dextral sense of shear. Less common, and possibly conjugate, are steep faults trending east-southeast with an apparent sinistral sense of shear. Offsets are generally less than 10 m on these structures. South-trending and shallow west-dipping brittle faults with offsets less than 1 m are also observed while rare steep, north-trending faults are also noted locally and played a critical role in development of the Zone 2 basement-hosted mineralization.

Jan 1, 2020

By Hong Zhong, Shuai Wang, Fangxu Li, Guangyi Liu

"The flotation performances and adsorption mechanisms of a-hydroxyoctyl phosphinic acid (HPA) to malachite, cassiterite and wolframite were investigated by micro-flotation tests and X-ray photoelectron spectroscopy (XPS) analyses. The micro-flotation results indicated that compared with styrene phosphonic acid (SPA), diphosphonic acid (DPA), benzohydroxamic acid (BHA) and salicylhydroxamic acid (SHA), HPA exhibited excellent collecting power to the three oxide ores. In addition, HPA showed superior selectivity against hematite, tourmaline, feldspar and quartz. The results of XPS analysis demonstrated that HPA reacts with active species (M) on metal oxide by formation of P-O-M or P-M bonds.INTRODUCTIONIn mineral processing, flotation has been the main process for separation and recovery of valuable minerals from complex ores (Mei, 2013; Zhou, 2014). One of the key requirements in flotation process is to increase selectively the surface hydrophobicity of the targeted minerals by surfactant (known as collector in flotation) adsorption so that these mineral particles can preferably attach air bubbles in a slurry or pulp (Bai, 2004; Hankins, 2004). To anchor a solid surface selectively, special functional group are designed to adjust the interaction between the surfactant and the active sites of solid surfaces (Wu, 2006; Huang, 2014).Organic phosphorous compounds have strong affinity toward metals or metal oxides because they form more stable metal complexes than metal carboxylates (Pazik, 2001; Zheng, 1998). In mineral engineering, phosphorous compounds have been exploited as metal extractants and flotation collectors (Alguacil, 2002; Sun, 2008). Ni (2012) and Zhang (1998) introduced diphosphonic acid (DPA) as an effective collector for flotation of fersmite and niobite. Liu (1999) found styryl phosphonic acid (SPA) was a superior collector for flotation recovery of finely disseminated rutile ores. Gruner and Bilsing (1992) thought SPA was one of the best collectors for flotation recovery of cassiterite which could obtain a high-grade concentrates of more than 40% with high recovery values. Bulatovic (1999) investigated the flotation performances of phosphoric acid ester (PAE) to perovskite, ilmenite and rutile and found that PAE was an impactful collector for selective flotation of titanium minerals from complex ores in the presence of petroleum sulfate. However, a-hydroxyoctyl phosphinic acid (HPA) as a flotation collector for recovery of titanium ores were hardly reported in the previous literatures."

Jan 1, 2016

By Kirsten Corin, Margreth Tadie, Cyril O’Connor, Jenny Wiese, Wonder Chimonyo

"Relating flotation performance to the electrochemical characteristics of a pulp remains a complex issue both in fundamental research and in practice. For example, in the case of thiol collectors different Eh values can result in the formation of the dimer or the metal thiolate which may or may not enhance the hydrophobicity of the mineral. Reducing or oxidizing conditions in a flotation system, viz. changing the Eh value, are usually manipulated to achieve an optimum flotation response by the control of pH and dissolved oxygen levels in the system. It is also possible to vary the potential by the addition of modifiers such as sodium hydrosulphide (NaHS), sodium hypochlorite (NaClO) or hydrogen peroxide (H2O2). The objective of the present study was to investigate the effect of the addition of the oxidising agents, NaClO and H2O2, on valuable mineral recoveries and grades in the flotation of sulphides from a PGM bearing Merensky ore. Batch flotation tests were conducted at pH 9.2, the natural pH of the system, in the absence and presence of a xanthate collector and Eh modifiers, viz. NaClO or H2O2. Most importantly in this way it was possible to vary Eh at constant pH and DO levels. The results indicate that in the absence or presence of xanthate the addition of H2O2 reduced both the recovery and grade of copper and nickel. In the absence of xanthate, the addition of NaClO improved the recovery of copper slightly and both the recovery and grade of nickel significantly, but in the presence of xanthate NaClO addition resulted in unchanged copper recovery and grade, but those of nickel were reduced. Based on anecdotal evidence that the addition of trace amounts of a potential modifier could improve flotation performance further tests were conducted the results of which suggest improved flotation performance.INTRODUCTIONIn the Merensky Reef, platinum group minerals (PGM) are commonly associated with base metal sulphides (BMS) and this has an effect on the way in which these minerals can be concentrated by flotation (Vermaak, Venter & Pistorius, 2004; Wiese, Harris & Bradshaw, 2005; Schouwstra, Kinloch & Lee., 2000). A major problem stemming from this association has been reported to be the loss of valuable minerals (PGM) associated with the loss of BMS (Wiese et al., 2005) during flotation. Shackleton (2007) suggested that PGMs behave in a similar manner to sulphides during flotation. Therefore, in order to recover the PGM, base metals are targeted. There is thus a need to investigate ways to improve the flotation performance of the sulphide minerals. The electrochemistry of the flotation of sulphide minerals has been studied for over half a century and there is consensus that sulphide minerals float only under a suitable redox environment (Heyes & Trahar 1979). This implies that reducing and oxidizing conditions during flotation of ores such as Merensky can be manipulated/varied to achieve an optimum flotation response.During flotation, sulphide minerals interact with thiol collectors in an electrochemical reaction to form hydrophobic species at the mineral surface (Finkelstein & Goold 1972; Rand & Woods 1984). The sulphide minerals are semiconductors and their interaction with collectors involves transfer of electrons. As such, a potential difference results which is responsible for driving electrons between reacting species (Fuerstenau, Jameson & Yoon, 2007). The magnitude of the potential difference affects the relative energies of charge carriers (electrons) at the mineral/solution interface hence controlling the direction and rate of charge transfer or rate of reaction (Bard & Faulkner, 2001). In a mixed mineral system the mineral/solution interface potentials account for the mixed potential which is critical to the process of flotation (Chander, 2003; Woods, 2003)."

Jan 1, 2016

Mining Association of Canada ! Represent base and precious metal, diamond and oil sands producers as well as nonferrous metal smelting and refining ! Member companies account for the vast majority of Canada?s mineral and metal production ! Mining is a major economic sector in Canada ! 13% of total exports ($47 billion) ! Employment near 400,000 ! 4% of GDP The Kyoto Protocol ! November 18, 2004 -- Russia deposited its instrument of ratification with the United Nations ! The Kyoto Protocol entered into force on February 16, 2005 ! The Kyoto Protocol is now an international and legally binding agreement to reduce GHG emissions world wide ! Canadian GHG target = 6 percent below 1990 ! First Commitment period 2008-2012

Apr 1, 2005

By S. I. Vobnout, J. Wm. White, J. P. Olson

"Mine management now recognizes the value of computer-based truck-shovel dispatching in open pit mines. The key tangible benefits are substantial productivity increases with a given fleet of equipment or, alternately, significant reductions in equipment required to meet production quotas. In this paper, the authors review the literature, report on efficient, optimal algorithms for haul truck dispatching in real-time, and briefly discuss methods used by various mines to evaluate productivity improvements over manual methods. Actual results obtained at thirteen mining operations around the world are also presented.IntroductionModular Mining Systems manufactures, installs, and supports its computer-based DISPATCH system at mines worldwide. DISPATCH is a large scale, computer-based mine management system which controls the dispatching of all haul trucks in any open pit mine (Fig. 1). When increased production is important, DISPATCH gets the needed production increase with fewer new or recommissioned trucks. DISPATCH also helps operations meet its blending objectives while minimizing rehandle and maintaining production. Furthermore, DISPATCH includes a powerful, eventdriven simulation subsystem. With the simulator mine management can pose ""what if' situations and see the predicted effect on production"

Jan 1, 1993

By M. Scobie, T. Atkinson

"This paper reviews the development of new designs in extensible and high angle conveyor systems. These aim to overcome the limitations of prior alternative concepts in design. The application of such systems in strip, terrace, open pit and mountain mining is reviewed. IntroductionTruck haulage costs have tended to escalate in recent years. This has been primarily due to operations generally moving to greater depths with associated increases in haul distances . Periods of high inflation rates have also been experienced for diesel fuel oil, tires and other petroleum based products. Recent international political events have tended to regenerate concerns over future oil supply and price stability. For such reasons, conveyor based transport is becoming increasingly attractive. Truck haulage maintains an inherent flexibility and improvements continue to be made in performance and capacity. Doubts must exist, however, over the extent to which further economies of scale may be made. Conversely, belt conveyor systems do not suffer this constraint and have the following advantages:• Electrical power is used and the specific energy consumption is at least half that required for truck haulage.• Operating costs and skilled labour requirements are lower.• Equipment has superior longevity and is ""inflation proof"" .• Access roads can be steeper and narrower in most mine environments, reducing construction and maintenance costs.• They are less prone to breakdown and bad weather delays .• In long haul, high capacity operations conveyors can save substantially on capital cost.• Environmental impact is improved with reduced noise level, dust and atmospheric pollution. Although conveyor systems are less flexible in operation than truck haulage and although a breakdown in any part of the system can immobilize the total system, mechanical availabilities of + 80% are constantly reported by large operators. There would appear in the past to have been some prejudice against conveyor systems in hard rock mines due to lack of experience. Apparent reservations would apply equally 10 underground coal mines, yet practically all of these mines (and some underground hard rock mines) find conveyor systems more economical than other transport systems."

Jan 1, 1991

By G. Danha, S. Wabula, D. Glasser, D. Hildebrandt, N. Hlabangana

"Impact tests on single particles or a bed of particles are used to determine the fracture characteristics of particles. Many different techniques have been adopted in comminution in order to find ways of optimizing energy consumption in the size reduction process. In this paper, we apply one such method called the Attainable Region (AR) analysis technique to optimize the impact energy on a bed of silica particles. The attainable region is a fundamental approach that is equipment-independent and can be used to analyze breakage processes. The AR is defined as a set of all possible outcomes, for the system under consideration that can be achieved using fundamental processes operating within the system.INTRODUCTIONThe energy crisis in Southern African has reached such critical levels, that most cities in countries like Zambia, Zimbabwe, Lesotho, Swaziland and even South Africa are experiencing load shedding challenges lasting sometimes up to 18 hrs a day. Southern Africa is well known for its riches in mineral resources, and the economies of most states in this region are driven by the mining & mineral processing sector. With the emergence of small scale miners due to government empowerment policies, national energy providers have had to resort to power cuts mainly to domestic users in a bid to cope up with the huge industrial electricity demands.It has been estimated that about 4% of the total energy used in the world is consumed by the mineral processing sector (Fuerstenau & Lutch, 1999). Tomanec and Milovanovic (1994) estimated that milling alone accounts for more than 50% of the total power used in mineral processing, but this can rise to as high as 70% for hard or finely dispersed and inter-grown ores. Today, the greatest challenge in mineral processing is how to optimize energy input to the size reduction process (Dey & Das, 2013; Nomura & Tanaka, 2011), where it has been observed that only a small percentage (1.5%) of the total energy input really does the breaking (Khumalo et al., 2008) while the rest is consumed by the equipment concerned and lost to contacts that do not result in breakage. The immediate benefits of focusing research on the optimization of energy in size reduction operations in the mineral processing sector lies in potential savings on industrial electricity usage that may then be directed towards domestic users."

Jan 1, 2016

By L. A. Melis, A. R. Marchbank, S. A. Webster

"Certain northern Saskatchewan uranium ores have a high content of nickel and cobalt which offer the potential for recovery as a by-product to uranium. A nickel/cobalt recovery process has been developed as a viable method of recovering a marketable concentrate from typical uranium raffinate solution.Impurities are first removed from the raffinate and the pure solution is then treated with sodium carbonate to recover a bulk nickel/cobalt carbonate precipitate for sale to a primary nickel producer. All contaminants of concern are removed to very low levels and the product is free of radioactive contamination with gamma emissions significantly below natural background. Cost estimates have shown that installation of a nickel/cobalt recovery circuit within a uranium process plant is economically feasible.The testwork that led up to the selected process is described along with recommendations for further investigations such as additional testing of hydroxide precipitation as a possible viable alternative to carbonate. The selected process is described and project economics are briefly reviewed.PROCESS TEST PROGRAMBackgroundExtensive metallurgical research has been performed over the years to develop a process for recovering uranium from the Midwest deposit in northern Saskatchewan. During the course of this research, a certain amount of information became available which suggested that recovery of nickel and cobalt from uranium raffinate could be economically feasible. It was decided to undertake a test program which would investigate methods of separating nickel and cobalt from radioactive and other metal contamination to permit production of a saleable product.Available technology suggested that three general approaches could be taken to recover nickel and cobalt. The first and simplest approach would be to selectively precipitate the impurities of concern, primarily arsenic, iron and radium, and then recover a bulk concentrate from the purified raffinate. The second approach would be to purify the raffinate and then remove cobalt from solution by solvent extraction producing pure nickel and cobalt solutions for further treatment. The third approach would be to precipitate all metals from solution and then selectively re-dissolve nickel and cobalt in ammoniac solution which would be further treated by solvent extraction for nickel recovery, leaving cobalt for further treatment."

Jan 1, 1993

By Richard Cyr, Peter Larsen, William Quesnel

"The need to continually improve efficiency and lower costs in mining operations is of paramount importance to all concerned in the industry. Mining operations are constantly testing new methods and equipment in order to lower costs and improve productivity. Equipment suppliers strive to fulfill the demands of the mines through improved design and innovative ideas for productivity increases. In some cases, however, an increase in productivity does not require new equipment design, but rather the application of an existing mining method into different operating parameters. Such is the case in applying longhole methods to narrow vein ore deposits.Bulk mining methods have long been recognized as efficient, low-cost alternatives in narrow vein operations. Typically, shrinkage and some cut-and-fill methods are employed. The shortfall of these methods is the tendency to be labour intensive. The demand for miners skilled in these methods far outweighs their availability. Consequently, labour-efficient methods have to be employed to fill the void. The application of longhole drilling techniques to narrow vein deposits is one such method.IntroductionPercussion longhole drilling evolved in Canada in the early 1940s. Prior to percussion drilling, blast holes were drilled using diamond drill equipment. Jack Gardner, of Gardner Steel, began testing with carbide percussion bits and extension drill steel in applications where diamond drills had been previously employed. Percussion drilling equipment proved to be considerably more productive and cost-efficient. The experiment eventually led to the replacement of diamond drills in this application.Over the years, the percussion methods were improved, with particular emphasis on the equipment used. Rifle bar rotation machines evolved to independent rotation. Bar and arm set ups evolved into self-contained mobile drill carriers that increased productivity while reducing the physical labour. The introduction of hydraulics further improved efficiency and production figures. Today, it is not uncommon to see fully computerized jumbos in production longhole drilling applications. These machines represent the ""state-of-the-art"" in longhole drilling equipment.Production longhole drilling is considered to be one of the most efficient bulk mining methods in use today. Production statistics normally exhibit low-cost, efficient ore extraction. As a rule, longhole (blasthole) methods are associated with substantial ore deposits. These methods have exhibited high production figures and low mining costs.Over the past decade, long hole methods have been applied to several narrow vein deposits. These applications have proven that, given the right parameters, longhole methods will produce the same advantages in narrow vein deposits as are seen in more conventional applications."

Jan 1, 1990

By P. M. STILES

Acquired in 1957, the limestone quarry of Ideal Basic Industries on Texada Island north of Vancouver has become a major supplier of high purity limestone and construction stone. Crushed limestone products are shipped by barge to various destinations along the B.C. and northern U.S. coasts.

Jan 1, 1984

By Trevor McGiddy

"Australia's prosperity relies significantly on income generated from exports of resources and agricultural products. In 1989-1990, coal was Australia's most valuable export commodity, contributing. A $5.7 billion or 14% of all export income.The abundance and quality of its coal resources and the proximity of Australia to the rapidly developing economies of Southeast Asia were significant factors that encouraged export-oriented growth and investment and will continue to do so. On the other hand, the 1980shighlighted the sensitivity of the industry to international changes in supply and demand, currency and socio-political forces.Following many years of disappointing returns for investors, mainly as a result of falling Australian dollar coal prices, resolve will be necessary to maintain competitiveness with resource-rich nations. In recent years, operators, unions and governments have begun to embark on a long overdue rationalization of domestic issues in a bid to increase productivity and reduce costs.The nature of mining operations is also changing; deeper surface mines and the growth of longwall mining will require the development of new technology and skills. Other challenges emerging from the international environmental debate will require that Australia responds appropriately to demands for cleaner fuels, energy efficiency and environmental responsibility.The future development of the Australian coal industry will therefore be influenced by its own ability to become more efficient and mature in the production of quality coal products and through rational international response to environmental questions."

Jan 1, 1992