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By Robert B. Parsons

"""I would be a rich man if I had a dime for every man hour spent by the bureaucracy on changing tax legislation."" Anonymous.The mind of a cynic might very well conjure thoughts about ""change for the sake of change"", given the protracted saga of federal sales tax reform in Canada. The latest chapter unfolded this summer when the Commodity Tax Review Group released its important report. Whatever sales tax changes, if any, are finally adopted will have profound effects on many aspects of doing business. The capital-intensive mining industry will not escape these effects.IntroductionThe Federal Sales Tax Review Committee, established by the Minister of Finance earlier this year, has published a report that is sharply critical of the government proposals to shift the incidence of federal sales tax from the manufacturer level to the whole sale level (sales to retailers). The Report recommends a continuance of the present manufacturer's tax, for the present, but with significant changes that would increase the tax cost on certain imports, smooth the administrative machinery and make appeals and determinations more open and equitable. For the longer term, the Report recommends a shift of the tax base to the retail level.Reform of the federal sales tax system has been under consideration for several decades. Briefly the history is as follows: 1940 Report of Rowell-Sirois Commission-proposed the eventual elimination of federal sales tax1956 Report of Federal Sales Tax Committee-proposed a shift in tax from manufacturer to wholesaler level1966 Report of Carter Commission-proposed shift to a retail tax1975 Discussion Paper on Federal Sales and Excise Taxation-concluded that retail tax conceptually best but provincial agreement/administrative problems present a major hurdle-proposed wholesale tax as best practical approach1977 Report of Commodity Tax Review Group"

Jan 1, 1983

By D. Bronkhorst, J. Rheault

"Backfill practices at the Williams mine have evolved significantly since underground mining began in 1986. The use of conveyors as a means of transporting fill material to stopes has been discontinued in favour of load-haul-dump equipment. The method of adding binder to the fill product has been refined along with the placement technique. Slurry preparation has been fully automated and flyash is now included as a binding agent. Surface preparation of the fill product has evolved substantially with the quarry operation coming into full operation and the construction of pennanent crushing, screening, and storage facilities. Company personnel have replaced all contracted labour involved in backfill operations. Some changes have been made to achieve a higher standard of quality control while others were implemented as a matter of cost reduction. BackgroundThe Williams mine is one of three mines operating at the Hernlo gold deposit, located 40 km east of Marathon, Ontario, along the north shore of Lake Superior. Daily production at the mine is 6000 Ud yielding an annual gold production of approximately 500 000 oz. The orebody extends from surface to a depth of 1300 m dipping north at 70 degrees. The average orebody width is 25 m, but varies from 45 m on the eastern boundary to about 10 m at the western probable limit and at depth. Proven and probable reserves currently stand at 32 million tonnes grading 6 g/t.The Williams orebody has been divided into four separate mining zones: the A-zone, the West-of-Dyke zone, the B-zone, and the C-zone (Fig 1). Ore production originally was from the A-zone open pit operation while the A-zone and B-zone underground workings were being developed. The mining method employed underground is blasthole open stoping with delayed rockfill. Mining block dimensions are nominally 20 m along strike by 25 m high. Stope extraction is sequenced to achieve a relatively short pillar life and 100010 ore recovery. Pillars are extracted as soon as the adjacent primary stopes are two cycles ahead. Primary stopes are filled with consolidated rock fill after mining. This allows pillars to be blasted right against the consolidated fill, but also requires that the fill be self supporting to a height of 30 m.The Williams mine places approximately 1.4 million tonnes of rockfill and 50 000 tonnes of binding agents each year, with about three quarters of the fill placed being consolidated. The consolidated fill placed at the Williams mine contains Portland cement and flyash as binding agents."

Jan 1, 1994

By Xianglin Yang, Hong Zhong, Jingjing Xiao, Guangyi Liu

"The selective adsorption of a flotation collector to a mineral plays a crucial role in enhancing the hydrophobicity of targeted mineral particles for attaching air bubbles in pulp. The recent progress of the structure-reactivity relationship of flotation collectors, the characterization methods for mineral surfaces with adsorbed collectors and their commercial application are reviewed in this paper. Particular emphasis is placed on the density functional theory (DFT) for understanding the reactivity of new collectors, the surface analysis techniques including time-of-flight secondary ion mass spectrometry (ToF-SIMS), in situ scanning electrochemical microscopy (SECM) and atomic force microscope (AFM) to characterize mineral/collector interface, and the flotation technologies for optimizing recovery of valuable minerals. Especially, the recently developing collectors such as Gemini, alkoxyalkylthiourea, dithiourea, amide-hydroxamate and oximido-thiol surfactants, and their specificity to given minerals are evaluated. Based on this crucial review, it is evident that the structural modification approaches for minerophilic or hydrophobic groups, and combined surface analysis approach for further understanding the adsorption mechanism of collectors on mineral surfaces will lay a solid foundation for the future development of flotation collectors. INTRODUCTIONIn mineral processing, flotation is the main process for separation and recovery of valuable minerals from the ores contained them (Fuerstenau et al., 2007). One of the key requirements in flotation process is to increase selectively the surface hydrophobicity of the targeted minerals by collector adsorption so that these mineral particles can preferably attach to air bubbles in a slurry or pulp (Fuerstenau et al., 2007). Flotation collector is a kind of functional surfactant, which is composed of polar and non-polar groups (Somasundaran, & Wang, 2006). Non-polar portion, commonly being linear, branch or ring hydrocarbon group, is termed hydrophobic group. The polar portion, exhibiting strong affinity to mineral surfaces, is known as minerophilic group (Nagaraj, 1988). According to mineral types including saline, oxide and sulfide minerals, flotation collector divides into sulfide and oxide mineral collectors. For efficient recovery of valuable minerals from the refractory complex ores, insights into the adsorption mechanism, hydrophobic model and subsequent flotation approach of flotation collectors have been regarded as an indispensable issue in mineral processing."

Jan 1, 2016

By Chris Blain

"Abstract - Based upon an extensive database, this paper analyzes the record of modern mineral exploration success and establishes the 50-year trends in discovery. The record clearly shows that the overall discovery rate rose during the 1950s and 1960s, peaked in the 1980s, and fell during the 1980s and 1990s. By commodity and ore-type target, the pattern of discovery is not continuous. Typically, it is episodic as a series of waves with minor resurgence. The waves reflect the order of the so-called discovery booms, led by uranium, then nickel, and copper, polymetallic base metals and gold. With the possible exception of gold, the discovery booms appear to be independent of metal price, although favorable perceptions of the price outlook may well have initiated the boom or led resurgence. Although difficult to quantify, an emerging trend in modern discovery is the integration of several detection techniques into the search process. No doubt, this trend will continue as orebodies become more and more difficult to find. The record of the past two decades shows that greenfield discovery rates have progressively fallen even though the level of investment in exploration has risen to an all-time high. This trend reflects increasing discovery risk. Several factors are contributing to this trend. Perhaps the two most important are: (1) deteriorating economics as increasing real costs and decreasing real prices continue to raise the economic hurdles for minimum acceptable exploration targets, and (2) increasing exploration maturity in many search terrains, particularly those in the traditional regions of North America and Australasia. To succeed cost-effectively in this new environment of increasing discovery risk will require extraordinary creativity, innovation, and technical skill coupled with commercial discipline."

Jan 1, 2000

By Marc Tardif

"The way alarm information is provided to an operator can make a huge difference in the minutes following an upset. Process alarms are often looked at as a way to help avoid catastrophic failure and serious accidents. But knowing that mineral processing is so energy consuming and that raw material is not consistent, all small upsets should also be seen as a catastrophe because they can have significant impact on product cost and quality.This paper will demonstrate how it is possible to use data from process alarms to provide operators with real time, value added information that will help them take the right decision at the right time and in turn, reduce unplanned downtime by 20 to 80% and incidents by up to 50% (number and cost),and optimize energy and capacity usage.In the era of Big Data, living in a world where we are submerged with information, one of the biggest challenges is to find the right information at the right time.Alarm rationalization projects will often focus on alarm quantity, but alarm quality is also very important. It is possible, by following a simple 6-step process to turn “alarms” into truly valuable information for operators. Based on known standards (ANSI/ISA 18.2 and EEMUA 191), this process will capture the knowledge of the best and most experienced operators and process engineers, and make it readily available to everyone, right on time, when it matters the most.INTRODUCTIONWhen spending some time in a modern control room, it is easy to notice the huge quantity of information that is available to the operator. Modern operation stations feature multiple screens with HD capability. These screens display information like process display, history trends, alarms and events list, maps with geo-located information, images from live cameras, etc. However, it is harder to assess whether all this information is really helping operators: Is all the information relevant? Are process screens overcrowded? Is the information easy to understand? Does the operator know what to do with all the information? Are there too many alarms?"

Jan 1, 2016

By Patrick Laflamme, Jean-François Boulanger

Les minerais de cuivre sulfurés, qui représentent 80% de la production mondiale de cuivre, imposent une étape de concentration des minéraux, premièrement pour atteindre une teneur en cuivre minimale qui permette le traitement pyrométallurgique, mais aussi pour limiter la présence d’élément pénalisants (délétères). Cette introduction offre un survol des principes, limites et pistes d’améliorations touchant la concentration des minéraux de cuivre.

May 2, 2024

By H. Clare Horwood

"Two structures, a fracture zone and a shear zone, contained the two orebodies that yielded all the ore mined at the Gold Eagle mine. The orebodies are known as the Gold Eagle vein and the No. 1 shear zone. Both structures occur close to contacts between Timiskaming sediments, Algoman diorite, and later Algoman granite-granodiorite. The structures were produced by compressive forces from a south direction acting in the southern part of the McKenzie-Gold Eagle stock and in a cylindrically shaped inclusion of Timiskaming sediments.The mine, which exhausted its ore reserves and ceased operations in September of 1941, is on the east side of Mackenzie island, in the centre of Dome township in the Red Lake area.The Gold Eagle vein was located during the summer of 1933 by a surface exploration programme carried out under the direction of Alex Gillies. Sub-· sequent diamond drilling and underground exploration led to the installation of a mill, which came into production in October of 1937. The No. 1 shear zone was discovered and explored later from a drive on the 500-foot level. The mine produced a total of 40,204 oz. gold and 19,157 oz. silver from 223,628 tons of ore hoisted (180,095 tons milled) during its 4 years of mill operation.GENERAL GEOLOGYThe ore-bearing structures trend S.61°E. across Timiskaming greywacke, Algoman diorite, and later Algoman granite-granodiorite. The greywacke is a large, cylindrically shaped mass that is separated from the mai~ mass by the later intrusives. It is a massive, light-coloured, quartzose variety that has been recrystallized by the enclosing granite. The diorite and the granite-granodiorite are early and late components of the McKenzie-Gold Eagle stock. The diorite, which is a porphyritic rock containing large crystals of andesine-labradorite surrounded by hornblende, was injected early in the Algoman period. It was intruded and in large measure surrounded by the later granite-granodiorite. This rock varies from a granodiorite near the mine to a granite in the centre of the stock. All three intrusions are massive and homogeneous."

Jan 1, 1954

By E. S. Moore

To properly understand industrial conditions in Spain it is necessary to consider the early history of the country. Spain is very backward in many lines. They use the sickle for cutting grain, and plows for cultivating the land, which resemble those of Biblical days. In the great mining camp at Bilbao only one steam-shovel is in use, although about two hundred million tons of ore has been produced, and this almost entirely from open cuts. It is the lack of industrial development, such as is found in many other countries, which permits large mining enterprises to be controlled almost entirely by foreign capital, although Spain is such an old country, and which permits mines opened in the days of the Phoenicians to still operate. Such deposits in America would be exhausted in a comparatively few years. The Phoenicians are supposed to have reached Spain about 1100 B.C. and to have worked some of the properties in the Rio Tinto district. The Carthagenians invaded the country about 236 B.C., and they were driven out about 205 B.C. by the Romans. The Romans ruled until 483 A.D., when they were overthrown by the Visigoths. Then, about 711 A.D., the Moors from Africa became prominent and they were finally expelled by the Spaniards in 1492. Spanish power reached its zenith under Phillip II, during the latter half of the 16th century, and since the close of that century the country has lost its prominent place among the nations. There are some evidences of revival in the development of good roads, the construction of a satisfactory network of railways, and the building of magnificent thoroughfares through the capital city, Madrid.

Jan 1, 1927

The PEMAC Commitment to World Class Industry in Canada The Plant Engineering and Maintenance Association of Canada PEMAC is a national, not-for-profit industry and technical association for plant and facility maintenance, engineering and physical asset management practitioners and professionals. Founded mid 80?s in the last century PEMAC is a knowledge based organization that focuses on sharing knowledge with our members and the profession. We provide education and professional development programs and certification for maintenance practitioners and professionals. We develop, produce and participate in conferences, seminars and trade shows.

May 1, 2008

By J. W. Merks

"The accuracy of a measurement on minerals and ores can be assured by applying suitable and unbiased procedures but its precision is a function of the number of primary increments and their mass, the number of lots per consignment or samples per shift, and the number of measurements on analysis fine samples.Experimental data will be used to show how the variance components for sampling, sample preparation and analysis contribute to the total variance on which precision statements for the final measurement are based. This type of experiment should not only form part of quality control programs at mines and smelters, but also underly the criteria on which the design of manual sampling regimes and mechanical sampling systems for bulk solids and slurries should be based.Sampling systems and regimes can only be adjusted and optimized if the variance component for each step in a quality evaluation process is measured. Knowledge of precision characteristics lies at the core of effective loss prevention and control programs."

Jan 1, 1985

Introduction ?MT involves the measurement of naturally occurring magnetic and electric field oscillations. ?The ratio of E/H (wave impedance) is measured as a function of frequency to give resistivitydepth information. ?The ratio of vertical and horizontal magnetic fields (tipper) gives information about the location of (channeled) current systems.

May 1, 2008

By Rodney S. Read

Both crystalline and sedimentary rocks are being considered to host a deep geological repository (DGR) for nuclear fuel waste in Canada. In the past several decades, considerable research has been conducted around the world to better understand geomechanical processes associated with development and long-term performance of a DGR. The Nuclear Waste Management Organization?s (NWMO?s) technical research and development program is examining a number of potentially suitable rock formations to support implementation of Adaptive Phased Management, Canada?s approach for long-term management of nuclear fuel waste. Rock engineering will play an important role in siting, design, and construction of a DGR for nuclear fuel waste. Post-construction activities such as excavation maintenance, monitoring, decommissioning, and closure will also involve rock engineering. The type of host rock selected for a DGR will influence the scope of rock engineering activities and related research requirements. This paper outlines key rock engineering aspects to be considered in developing a DGR in sedimentary rock.

May 1, 2009

By R. W. Nice

"For many decades the incidence of a highly active graphite-like ore has plagued the McIntyre mine. This ore acts as a precipitant of the gold complex immediately upon formation of this complex. The gold is subsequently discharged with the tailings.Many different methods have been devised by various researchers all of which proved inapplicable for the McIntyre problem.Recently, McIntyre personnel, through their own research, developed a flowsheet. This circuit should give an overall recovery of 36% which is below the 94% experienced in the mill at present. Therefore, less revenue would arise from treatment of these ores. On the other hand there exists a possibility of more efficient mining methods in some of this ore thus allowing more economic recovery.INTRODUCTION This paper has been prepared to serve two purposes:i) To propose a method of recoverying gold from a sizeable orebody at the McIntyre mine at Schumacher.ii) To summarize and present the many methods suggested to solve a very old but very real mineral dressing problem familiar to the industry as long as cyanidation itself."

Jan 1, 1971

By G. Labonté, J. Truskoski, A. Kerr, A. Bouchard, J. Barrett

"Improving mill grade recovery relationships is always good business. Inco’s Clarabelle mill has just undergone a $16 M process upgrade that was designed to improve nickel recovery by 2%. The “Mill Redesign Project” was completed on time, under budget and delivered the promised improvement in recoveries.This paper describes the methodology of the Mill Redesign Project team, details of the process improvements and the critical success factors that helped the team deliver on its promises.With a payback of under one year, the Mill Redesign Project will play a key role in ensuring a competitive edge as Inco embarks on its second century of operation. IntroductionIt is not uncommon in milling operations to encounter a crisis. That is the point when the process does not behave as expected and fails to respond to the increasingly desperate efforts of the metallurgists and operators. Flowsheet and process changes are attempted and abandoned. With luck, one or more of the changes achieves some mitigation of the original problem or more usually, the original cause of the problem disappears. Regardless, the metallurgist can sit back and bask in the apparent success of his or her endeavours.Less common is when a problem is carefully diagnosed, a team put together to explore all avenues and recommend a path of action that is implemented on time, on budget and immediately delivers on the promises which are sustained over time. This is one such story. It is the story of the Mill Redesign Project at Inco’s Clarabelle mill in Copper Cliff, Ontario."

Jan 1, 2003

By B. Dubreuil, J. -M. Lalancette, D. Lemieux

Arsenical bearing deposits are posing an increasing challenge for the mining industry. In particular, mineral processing of arsenical sulfidic ores for base and precious metals recovery tend to produce problematic arsenical tailings. This arsenic being present as sulphide or oxide, tends to dissolve, contaminating surface and underground waters. To meet the environmental regulations, it is often required to stabilize the arsenic in a more insoluble form. Dundee Sustainable Technologies has developed a new patented technology using vitrification of the arsenic oxide in an economical way, giving a stable solid, well below the environmental regulations upon leaching. This technology involves oxidation of As (III) to As (V), by using a low cost natural oxidizer and transformation of the produced arsenic oxide into calcium arsenate, which is not volatile at the melting temperature of the glass. This technology would be advantageously applied on most cases around the world where sulphide concentrates are oxidized in a fluidized bed or smelted.

Jan 1, 2014

By Richard W. Hutchinson, Christopher Osterman

The Selebi-Phikwe deposits are hosted by amphibolite to granulite facies gneisses of the Limpopo belt. The sulfide orebodies are generally stratiform and conformable to the foliation of the wallrock gneiss. Sulfide remobilization has occurred during metamorphism and has produced discordant sulfide veins, called piercement structures, which project into the hanging wall and footwall gneisses. These piercement structures are compositionally similar to the stratiform sulfides, consisting mainly of pyrrhotite, pentlandite and chalcopyrite. However, texturally the piercement sulfides are coarse grained and inclusion-free, whereas the stratiform sulfides are fIne grained and packed with tectonically produced wallrock inclusions. The piercement structure sulfides and adjacent stratabound sulfides were sampled and analyzed for major base metals and PGE's for comparative purposes. Most of the piercement structures were enriched in Cu, Ag and Au, whereas they were generally depleted in Ni, Co, Fe and PGE's. Changing elemental associations were observed from the stratabound sulfides and along the length of the piercement structures. This and the degree of depletion or enrichment of various major and minor elements in the sulfide piercement structures may reflect the relative mobilities of metals under metamorphic conditions. The similarities between sulfIde piercement structures and the footwall Cu-PGE veins in some Sudbury deposits are reviewed.

Jan 1, 1994

By Robert B. Parsons

"The February 18, 1987, Federal Budget contains a proposed amendment which would simplify somewhat the ""successor corporation"" rules in the Income Tax Act. Despite this amendment, though, the important successor rules will continue to be relatively complex.IntroductionThe February 18, 1987, Federal Budget papers propose an income tax amendment whereby the so-called ""successor corporation"" rules would be revised by removing the present provision which limits the application of these rules to a maximum of two ""successions"". The successor corporation rules represent one of the most complicated sets of rules in the Income Tax Act. This month, Tax Notes seeks to explain these rules and the proposed amendment in simplified terms.Basically, the successor rules provide a mechanism for transferring unused exploration and development expenses from one taxpayer to another , in specified circumstances. The aforementioned limitation of two successions refers to the rule which allows a maximum of two such transfers with respect to any particular pool of deductions."

Jan 1, 1987

By Ken G. Stowe, Stephen L. Chryssoulis, Christian Bendel, Joe Y. Kim, Ewald Niehuis

"TOF-SIMS (Time-of-flight secondary ion mass spectrometry) was used to detect collectors sorbed onto the surface of mineral particles in concentrate and tailings samples from the Brunswick, Matagami and Kidd Creek concentrators. This technique uses ion beams from either Cs or Ga sources to sputter the particle surface, a method which reduces fractionation of the collector molecule during sampling.In the Brunswick Zn circuit, sphalerite particles lost to the scavenger tails had less amyl xanthate and isobutyl xanthate compared to sphalerite recovered to the Zn final concentrate. Xanthates were detected on the surface of sphalerite particles floating to the CuPb final concentrate.At Matagami, significantly more isopropyl xanthate and isobutyl dithiophosphate were detected on sphalerite recovered to the Zn final concentrate, compared to sphalerite lost in the Zn rougher tails.In the Zn circuit of Kidd Creek, sphalerite lost to the tails had on average ten times less xanthate compared to sphalerite recovered into the Zn final concentrate. Xanthate was also detected on the floated pyrite particles. In addition to isobutyl xanthate, amyl xanthate was also detected on the floated sphalerite and pyrite particles.This preliminary investigation has (a) demonstrated the ability of TOF-SIMS to detect individual collectors on particle surfaces from plant samples and (b) shown that TOF- SIMS is an excellent tool, complimentary to TOF-LIMS, in establishing the surface chemistry of minerals as related to mineral processing."

Jan 1, 1995

By E. Norton

"Even though the subject of this panel discussion is dust control, rather than dwell on the design aspects of dust collection systems which are well documented in numerous publications, :it was considered more pertinent to the present economics of mining to examine the energy costs involved.At the present time, the facts of shrinking fossil fuel reserves and spiralling fuel costs are being constantly brought to our attention. Industry is being motivated to consider the possibilities of incorporating heat recovery systems in areas where they prove to be economical. Unfortunately, it is not a simple exercise to determine if the installation and operation of heat recovery equipment is feasible and economical. Each process involving heat recovery potential must be thoroughly studied in all aspects.In a paper presented at the 1975 Annual General Meeting of the Canadian Institute of Mining and Metallurgy in Toronto, Ontario, entitled ""The Influence of Energy Conservation on Concentrator Design"", it was stated that the largest single energy consumer in winter is space heating with the largest portion of this supplied to crushing and screening plants. (1) Within the scope of this panel discussion we will study, as one example, a crushing and screening plant using natural gas heat in the province of British Columbia and we will explore the feasibility and economics of installing air-to-air heat recovery equipment."

Jan 1, 1976

By N. Katsikaros, R. Agius, B. Adaszynski

"With stricter limits globally being imposed on cyanide discharge levels in plant tailings, having a reliable and well designed cyanide detoxification circuit is critical for any operation. The INCO SO2/Air method is most commonly used for cyanide detoxification where sulfur dioxide and oxygen combine to oxidize cyanide to the much less toxic cyanate. This paper discusses the steps involved with the development, from laboratory through to design, of a robust cyanide detoxification circuit. The goal is to produce a cyanide detox circuit that reliably meets discharge target with the lowest operating and capital cost.Design begins in the laboratory where continuous tests simulate full scale operation of a detoxification circuit. Detailed design relies on several design parameters, based on theory and experience, to ensure the reactor can satisfy requirements of the cyanide destruction reaction. Selection of the correct reagents and their supply to the reactor is important to an operable process with minimal operator workload. The operability of the system relies on correct process control strategies to maintain optimal reagent addition and chemical conditions in the reactor. These design factors are critical to providing a robust plant that will consistently meet cyanide discharge levels, ensuring uninterrupted production and plant profitability."

Jan 1, 2014