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INTINERARY ?What is SRI? ? How do we define good corporate social and environmental performance in the mining and petroleum industries? ? Why should you care? MJRA Inc. ? Established in 1992 ? Canadian Social Investment Database (CSID) launched in 1993 ? Jantzi Social Index launched in January 2000 ? created in 2000 SRI is ?the incorporation of social and environmental parameters into the investment decision making process.

May 1, 2002

By Yongqiang Liu

Background For refractory gold ores with high carbonate contents ! Acid pressure oxidation ! High acid consumption (if low sulfur content) ! Low oxidation efficiency due to CO2 in autoclave ! Problems with slimy precipitates (gypsum, etc.) ! Alkaline pressure oxidation ! Difficulty in fixing arsenic ! Low gold dissolution due to iron hydroxides/oxides coating ! High reagent costs Summary ! Carbonate and sulfide minerals had similar floatability across the pH range tested (5 - 12) using sodium oleate as a collector; ! Thioglycollic acid or citric acid depressed the flotation of pyrite but could not depress chalcopyrite when used alone; ! Combination of thioglycollic acid and citric acid had a much stronger depressive effect, and the mixture depressed chalcopyrite as well as pyrite between pH 8 and 11 without affecting the flotation of calcite and dolomite; ! Calcite could be separated from chalcopyrite and pyrite; dolomite could be separated from pyrite but not from chalcopyrite under the tested conditions.

Apr 1, 2005

By J. Yue

The particle breakage kinetics, product size and size distribution, as well as grinding limit for quartz suspensions in a horizontal stirred mill are investigated. Results of grinding studies on quartz suspensions in a horizontal stirred mill confirm "first-order" particle breakage rates. A comparison of equation fits reveal that the product size distribution from stirred mill is best represented by the Rosin-Rammler equation when compared to the Gaudin-Shuhmann equation, but results fit poorly as particle size below five microns. A method of determining breakage rates versus particle size is demonstrated which shows that the 10% top size fraction is most appropriate for the determination of specific breakage rates. The method is used to demonstrate the relationship between particle breakage rate and particle size. As the feed particle size becomes smaller, the size reduction ratio decreases and approaches a grinding limit which depends on the effective stresses created in the mill.

May 1, 2004

By G. L. Palmer

"In 1986, anomalous sampling results for heavy minerals were obtained at various sites in Namaqualand on the west coast of the Cape Province. Drilling in 1987 at Graauwduinen penetrated up to 35 meters of heavy mineral-bearing Tertiary sands which extend several kilometers inland from the coast. The heavy mineral suite includes ilmenite, rutile, leucoxene, zircon and monazite, along with gamet, pyroxene and amphibole. Three deposits are recognized, two of which comprise the resource to be mined by Namakwa Sands Limited, a recently formed Anglo American Corporation subsidiary company.Mineable reserves in excess of 500 million tonnes have been delineated, sufficient to sustain mining for over 35 years at projected production rates. During the feasibility study, on-site investigations included test mining at various sites to assess rnineability and to provide material for metallurgical testing in a pilot plant located at the site. llmenite produced at the mine will be smelted at a new facility to be built at Saldanha Bay. Saleable products comprise titania-rich slag, pig iron, zircon and rutile.During the exploration phase, company environmental guidelines were established and monitored. The feasibility study incorporated a Class 1 Environmental Impact Report, the contents of which were made public following the principles of the Integrated Environmental Management legislation."

Jan 1, 1994

By S. Shokri

The increasing size and complexity of mega construction projects result in having several geographically distributed stakeholders, collaborating with each other to successfully deliver the project. Electronic Product and Process Management Systems (EPPMS) are recently emerging to facilitate the collaboration between stakeholders, reduce the surprises and issues, and improve the project productivity. These are commercially successful but evolving systems. An important component of EPPMS is the Interface Management System, which aims at formalizing and automating the communication channels between stakeholders. An interface is generally considered the link between construction elements, phases, or stakeholders. An interface Management System (IMS) involves five iterative steps: (1) Interface Identification, (2) Interface Documentation, (3) Interface Transferring, (4) Interface Communication, and (5) Interface Closing. A fundamental part of step 2 is recognizing different roles in dealing with interfaces. Each stakeholder is assigned a different role, such as responsible, accountable, consulted, and informed. In a mega project, several thousands of interfaces exist with complex relationships between stakeholders. Therefore, identifying stakeholders with higher responsible roles has been requested as useful information to the project owner in dealing with some of the project risks. After the interfaces are determined, and the responsibilities are allocated, the critical stakeholders are identified using the centrality concept in Social Network Analysis. The critical stakeholders can be determined at the highest level, considering all types of interfaces, as well as for each specific type or discipline-related interfaces. The proposed methodology is applied on a hypothetical offshore project with over 500 interfaces. In fact, this project is a simplified representation of a real scale Liquid Natural Gas project. In order to reduce the complexity of calculations and clarity of explanations, the simplified case study is used. By implementing IMS in mega projects, different parties not only formalize the communication between each other, but also gain better visibility concerning their roles and responsibilities. In addition, the owner benefits from analysing the complex relationships between stakeholders to further identify critical ones, along with other criteria like package cost, stakeholders? experiences, etc.

Aug 1, 2013

By W. J. Wright

Summary Statement The following notes on the geology of the Grand Lake coalfield are intended to be introductory to a second paper being read at this meeting, which paper will describe the earlier and the more modern mining methods. The coal industry of the Grand Lake coalfield is centred chiefly within a three-mile radius of Minto, but minor operations are dotted over an area of approximately 50 square miles extending easterly to the vicinity of Chipman and Coal Creek (see Figure 1). The coal comes from one seam of Pennsylvanian age. The seam varies in thickness from 16 to 30 inches and lies almost horizontal at depths of 0 to 125 feet. It has been mined and prospected over an area of approximately 150 square miles, but in a portion of this area the commercial possibilities have been destroyed by erosion. The industry is the oldest of its kind in North America, but it did not at tract particular publicity until about 1914. Since that date, mining methods have improved and the output has rapidly increased until, in 1934, it amounted to 271,335 long tons, and furnished employment for about 1,000 men (1). Approximately 73 percent of this amount was produced by the Minto Coal Company, the Miramichi Lumber Company, the Avon Coal Company, and Welton and Henderson, and 25 per cent by the Rothwell Coal Company, Harvey Welton Limited, G. H. King, the Reade Construction Company, and the Newcastle Coal Company. The remainder was produced by J. W. Carter, G. D. Crossman, T. H. Swift, C. S. Yeamans, and several other small operators. The coal is won by underground mining, except in the case of the Reade Construction Company, and a minor operation by Ashfield and Pieton, who have employed open stripping. It is mined only as required to fill definite orders, and is loaded directly into cars for shipment. In 1934, the larger mines did not operate full time, and the production could easily have been increased if markets had been available. The coal is sold in four grades: screened or lump, run of mine, slack, and stripping. The chief market is with the railways and commercial plants, with a fair amount for domestic purposes.

Jan 1, 1935

By Walter Greaves

THIS paper describes a series of tests performed at the Hollinger mill during the past four years, in which both metal and rubber-lined pumps were used for pumping sand and slime. While conditions will not be the same at other mills, it is felt that the information gained from the tests should be of value to other operators and of assistance to them in selecting the most efficient size of pump and kind of lining for economical operation. For the successful operation of pumps with rubber linings there are certain conditions, which, if recognized at the outset, will save the operator a good deal of work and trouble. First is the necessity of keeping sharp pieces of steel, or anything that might cut the lining, out of the pumps. This can be effected by placing screens in the proper locations. Second is to recognize the fact that the rubber lining of the shell, and the rubber cover of the impeller, are subjected to very different conditions. The shell lining, :being at rest and well supported by the metal case, has a relatively easy job compared ? with the impeller covering, which is subjected to centrifugal force and has a tendency to tear itself away from the metal core. Also, the pulp travels through and past the impeller at a high velocity. These two factors, centrifugal force and velocity of the pulp, would appear to set a limit to the speed at which, for a given set of conditions, it is economical to run a rubber-covered impeller. Therefore, a pump should be large enough for the work to be done. To get the best mechanical efficiency, it must be operated somewhere near the limit of its capacity, but this may not give the best overall cost, because the saving in power, due to the high efficiency, may easily be lost through excessive wear on the lining. It would appear that this condition is more critical in a rubber-lined pump than in one lined with metal.

Jan 1, 1939

By A. West, F. Mohammadi

Growing awareness of selenium bioaccumulation has resulted in selenium management becoming an important environmental issue for mining operations. Selen-IX™ is a novel ion exchange based technology developed by BioteQ to provide an effective solution for removing selenium oxyanions from mine impacted water to single-digit µg/L levels. The technology offers significant potential benefits when compared to incumbent biological treatment processes, including substantially reduced capital and operating costs and significantly reduced production of a selenium-containing sludge for final disposal. This paper reviews the key features of the Selen-IX™ process and presents the results of recent pilot testing on selenium impacted water.

Jan 1, 2014

By A. W. F. Smith, P. B. Prangnell, D. N. Crowther, P. J. Apps

It is well known that the refinement of grain size in metals leads to a significant improvement in important mechanical properties. As part of a European collaborative project, processing schedules have been investigated aimed at producing a homogeneous ultra-fine ferrite and spheroidised carbide aggregate microstructure structure in high carbon (CMn) steels (0.6-1.2wt%C), via conventional 'warm' rolling and innovative Equal Channel Angular Extrusion (ECAE). Suitable deformation schedules were determined from dilatometry and thermo-mechanical Gleeble simulations. Evidence of an ultra-fine ferrite and carbide aggregate microstructure following 'warm' rolling is given. A significant improvement in tensile strength, particularly proof stress (0.2%) was also noted in comparison to material deformed at higher temperatures. Concurrent Equal Channel Angular Extrusion (ECAE) experiments investigated microstructural evolution with incremental strain. Extensive analysis was carried out using various techniques, including high resolution Electron Back Scattered Diffraction (EBSD). Evidence of ferrite grain refinement was noted in a eutectoid composition steel. A sub-micron ferrite structure was observed following high strains (E-3.33) and the mechanical properties exhibit a marked increase in tensile strength.

Jan 1, 2004

By Parsons. Robert B.

"Starting this year, corporations that conduct business in Ontario face a new tax a corporate minimum tax. This tax is in addition to the myriad of other taxes that make up a corporation's total tax burden including federal and provincial capital 1oXJ!S, payroll tax and sales taxes. Mining companies with gross revenues in excess of $10 million or total assets exceeding $5 million may be liable for this new tax. IntroductionOn December 8, 1993, the Ontario government introduced legislation to implement the corporate minimum tax (CMT promised in its May, 1993 budget. There are very few differences between the final legislation and the budget proposals.The CMT is effective for taxation years commencing after 1993. Subject to certain specific exemptions (detailed below), the tax applies to all corporations liable for Ontario Corporate Income Tax that have either gross revenues in excess of $10 million or total assets in excess of $5 million. These measurements apply to the aggregate gross revenues and total assets for all corporations in an associated group and a corporate partner's share of partnership assets and revenues must be included in the determination.In essence, the CMT is an income tax that is based on financial statement profit instead of an income amount that is determined separately under a statute. Accordingly mining companies (including so called ""junior"" exploration companies), which traditionally sheltered their taxable income by claiming generous exploration and development deductions, could find that they have a CMT liability."

Jan 1, 1994

By L. Hacini, N. Van L ê, P. Bacher, D. Thibault

Manufacturer welded components may suffer from high level of residual stresses which can cause premature cracking and decrease the life of the components if they reach values close to the yield strength of the material. In the present work, a robotized hammer peening technique is simulated by an impact machine and the residual stresses generated by the indentation are measured. To better understand phenomena behind residual stresses relaxation by hammer peening, the impact energy level was changed. 304L steel plates were hammer peened with 10 impacts. The contact between the hammer and sample surface was always at the same location. The strains on the surface close to the impact location were recorded during the test using strain gauges to follow residual stresses variations. At the end of the test residual stresses were measured indepth using hole drilling technique at 8mm from the impact center. The micro-hardness was monitored to evaluate the affected zone by the hammer peening. This approach gave a good estimation of the energy and number of blows to be used for efficient relaxation of the manufactured parts.

Jan 1, 2006

By K. Ogawa, T. Yokoyama

Hydraulic fracturing technique, an applied technique to cause tensile fractures to rock by injecting water pressure to a certain closed section of the borehole, is a measurement method of in-situ rock stress. This technique has the highest track record for techniques used in sub 1000 meter. A feature of this technique is comparatively simple and easy for in-situ stress measurement, because the measurement is applicable when a drilled borehole is available. The predominant advantage of this method is that elastic constants such as Young’s modulus and Poisson’s ratio are not required for determining the value and direction of initial stress. The factors to determine the stress state are the water pressures of re-opening and shut-in of fractures around the borehole wall and its directions. With conventional methods, however, the accuracy of the derived stress states from the observation equations was often adversely affected by the lack of consideration of the remaining water pressure in fractures and insufficient stiffness of the pressurization system. We have developed a new hydraulic fracturing system based on a new test method concept overcoming these defects, and applied to a 300 meter deep borehole in granite. The most important improvement of the new system is an employment of a syringe pump which enables an accurate flow control of fluid with less than 1ml/min in the pressure of 30MPa. Therefore the new test system has a quick response for pressurising in the interval zone, and the measured data was confirmed extremely accurate.

Jan 1, 2015

By W. A. Grell

"The oxygen meter has been in use at MacLeod Cockshutt Gold Mines for over a year, At MacLeod about 200 tons per day of reground concentrate containing roughly 10% pyrrhotite and 20% pyrite is cyanided in four 181 x 18' Dorr agitators. A survey by the Department of Mines showed that oxygen content of some of the agitators was rather low. Experience with our oxygen meter indicates that the oxygen content must at times have been too low for good gold dis solution.We have found that in winter, when pulp temperatures drop to about 50° F, oxygen saturation in the agitators is not difficult to maintain. In summer, however, when pulp temperatures rise to 70or 75°F, the oxygen content will drop very readily. It was found that a high oxygen content can be maintained readily if the pulp is sufficiently dilute. Thus at 50° F, a pulp of specific gravity 1. 75 i.e., about 55% solids, will saturate; but at 70 or 75° F, the specific gravity must be decreased to 1 .45, equivalent to about 40% solids, in order to maintain saturation. Very thick pulps, such as thickener underflows, are noticeably difficult to saturate in the laboratory, and lose their oxygen rapidly.Clear solutions, on the other hand, absorb oxygen readily and hold it. The primary thickener overflow, before agitation, is 100% saturated; after storage of 3 to 4 hours it is still 100% saturated at re clarifier tank. Barren solution after spraying in a launder is 100% saturated.We have not yet attempted to determine what percentage saturation is necessary for good extraction, but it is known that there is a point at which extraction decreases rapidly. So far, the measures required to maintain over 80 or 90% saturation have coincided with measures required to hold the reducing power to the point believed necessary."

Jan 1, 1964

By G. Szilvay, P. Kinnunen, J. Salminen, V. Miettinen, O. Salmi, J. Mäkinen

This paper demonstrates experimental studies on bioprocessing of different waste streams. In Part I of this paper three tailings from mining industry were bioleached with mixed acidophilic culture in order to solubilize valuable metals, like copper, nickel, zinc and manganese to leaching liquor. Bioleaching resulted in > 70 %, > 85 %, 100 % and > 70 % leaching yields for Cu, Ni, Zn and Mn, respectively. However, contaminants like arsenic and chromium were not leached efficiently and they will cause challenges in residual solids and sometimes also in metal recovery from leaching liquor. Bioleaching resulted in 99 % leaching yield for copper. Part II demonstrates mine water treatment and also gold recovery from process liquids with biosorption method. The novelty of biosorption was finding that certain fungal species were able to be cultivated to self-immobilized systems, which are easier to operate than traditional suspended biomass methods. Biosorption resulted in more than 90 % removal for all contaminants, but was also seen to be gold selective.

Jan 1, 2014

By Dr. Rory Cameron, Dr. Terry Cheng, Dr. Nadia Mykytczuk, Ian Bedard, Kristie Tarr, Ruth Joseph

Pyrrhotite-rich tailings from Sudbury, Ontario mining activities are known to contain significant amounts of EV metals, such as nickel and cobalt.  CanmetMINING has developed a novel bioleaching process for recovering the nickel and cobalt (both critical for vehicle electrification) from tailings that incorporates partial neutralization and iron removal in the bioleaching circuit; bench- and pilot-scale tests have resulted in excellent nickel and cobalt recovery over a range of temperatures.  However, this process generates a new bioleach residue, which is heavier and more voluminous than the original tailings due to pyrrhotite oxidation and jarosite formation during the bioleaching process. This residue can be problematic for long-term disposal. A possible solution being studied for this issue is using mine backfill as a disposal mechanism.  Underground backfilling allows for effective re-purposing of mine waste, however the backfill must also be able to withstand a certain load, since in most cases it is used as an underground construction material, such as in cut-and-fill mining methods.  Therefore, the composition of the mill tailings must be such that when combined with a binding agent and pumped underground, the slurry or paste is then able to withstand a certain load within a certain period of time.  Unfortunately, high-pyrrhotite content tailings, commonly found on mine sites in Ontario and Quebec, are reactive and can easily oxidize and produce acidity and/or metal-laden drainage under some disposal conditions. This means that the pyrrhotite in the tailings can lead to acid mine drainage if stored on surface, however, it can also cause strength degradation if re-purposed in too high a concentration in underground mine backfill.  The research being done at CanmetMINING related to the bioleaching process is aimed not only at recovering nickel and cobalt from mine tailings, it is also being used in an attempt to neutralize the tailings to reduce acid mine drainage and backfill strength degradation. This paper reports on research designed to evaluate different options for transforming the bioleaching process residue into iron oxide phases, for better environmental footprints if stored on surface, as well as increased disposal possible, if re-purposed as underground mine backfill material.  

May 4, 2025

By F. Hassani, J. Peck, D. J. Lucifora

The performance of a rotary blasthole drill is heavily dependent on the material being drilled. This material is a microcosm of the in-situ geology that makes up the surface mine in which the rotary blasthole drill is deployed. The performance metrics that are influenced by the in-situ geology are penetration rate (distance drilled per unit time), rotary torque and to a lesser extent rotary speed and vibration. For simulation and testing purposes it is useful to have a validated plant model based upon the application of study. Once validated, a plant model can be used to perform simulation based testing as a supplement and possibly in place of more expensive and logistically complex field testing. Previous studies in the field of rock mechanics have supplied proven models that relate the performance of a rotary blasthole drill to the material being drilled for a given rock type with a given drill bit. In this study, field based experiments were conducted in an active surface mine on a working rotary blasthole drill and the corresponding monitoring while drilling (MWD) data was recorded. Data analysis was then performed on the collected field data. The techniques used successfully fit the collected MWD data to the previously proven rock mechanic models. This paper explores the theory relating rotary blasthole drill performance to the material being drilled, illustrates the required data collection and data analysis techniques, and demonstrates the ability of these techniques and the known rock mechanic models to provide a simulated plant model for the drilling process that can then be validated. This validation is also discussed.

Jan 1, 2015

By J. H. Douglas, A. F. Matheson

"The Hard Rock is the most easterly producing mine in the Little Long Lac area. The Company was formed in 1934 to develop a surface showing of gold in quartz made by a prospector, W. W. Smith, in 1931. Although some ore was eventually produced from this discovery, the principal orebody, hidden below 10 feet of muskeg, was found about 1,000 feet to the north by exploratory diamond drilling early in 1938 from the No. 2 shaft workings at the 250-foot level.Production started in 1938 and to January 1, 1947, 201,000 oz. gold had been obtained from 1,165,282 tons of ore mined and 869,397 tons milled. Of this ore about 15 per cent came from the development and mining of the original orebodies discovered at the surface. The remainder came from the ore found by the underground diamond drilling done in 1938. Of the latter ore, the Company estimated, at January 1st, 1947, only 140,000 tons remained. The orebody, therefore, contained approximately 1,100,000 tons.OREBODIES AND GENERAL GEOLOGYThe orebodies of the Hard Rock mine are of two main types: the quartz ore of the south and No. 1 shaft zones, and the sulphide ore of the north zone. The quartz ore consists of white quartz veins mineralized with sparse, fine, light-coloured pyrite, or, less commonly, nests of coarse, crystalline, light pyrite. A little tourmaline, scheelite, pyrrhotite, chalcopyrite, arsenopyrite, and native gold are also present. Native gold occurs in a few places in quartz veins in exceedingly rich cemcentrations, apparently where there are large, light-coloured, pyrite crystals of imperfect form. The ore of the north zone is massive pyrite with arsenopyrite and in places pyrrhotite. Many short irregular quartz veins, from a few inches to 2 feet in width, are also present, but the quartz forms a very small percentage of the whole. The veins may be flat to vertical, and sulphides on one or both sides replace the host rocks. The gold is closely associated with the sulphides . The quartz is commonly barren except where it contains sulphides or along the borders of the sulphide ore zone where native gold is not uncommon in quartz stringers."

Jan 1, 1954

By M Safa

Addressing deficiencies and defects that occur during construction projects is costly and time consuming. The manual quality assurance programs currently used in the industry have certain limitations, including human error and lack of consistency. Hence, there is a need for integrated electronic models that employ new technologies and methods. This research introduces an integrated construction quality control system that has the potential to improve quality management processes in the construction field for piping construction, which is a complex process often requiring rework. The proposed integrated system relies on data collected from construction sites using photogrammetry and laser scanning, which is then used to compare actual work performed to that designed. The proposed system aims to improve the promptness and accuracy of quality assurance processes, in particular dimension measurements, by avoiding human error and integrating defect detection and quality management. The use of this system has highlighted some of the limitations during data fusion and acquisition process, which are highlighted in this paper. These aspects must be considered to increase the reliability of the acquired information.

Aug 1, 2013

By B. B. Adhikari, S. Alam, Ohto Kawakita, Abe Pangeni

Effective recovery of gold was investigated by using adsorption gels prepared from pure cellulose, cotton and paper by treating with concentrated sulfuric acid. Only gold was adsorbed with extraordinary high loading capacity from varying concentrations of hydrochloric acid separated from other precious metals and base metals. The formation of fine powders of metallic gold was visually observed, which is attributable to the selective reduction of gold (III) ion to metallic gold clue to its high oxidation-reduction potential. Recovery of gold from the leach liquor of hydrochloric acid of circuit boards from spent mobile phones was attempted using pure cellulose gel.

Jan 1, 2011

The New Zealand opportunity NZ?s only significant phosphate deposit 1 million tonnes imported annually - mostly from Morocco US $180/t + $75/t freight

May 1, 2013