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By Jeff Bird, Xijia Wu, Prakash C. Patnaik

"Prognosis and health management (PHM) is an evolving suite of technologies intended for application to the life cycle management (LCM) of mission/safety critical systems, with anticipated results, which will: - Reduce life cycle cost - Enhance operational safety and readiness - Assist in maintenance decision-making - Enable autonomic logistics While it is emphasized in the United States that future multi-mission fighter aircraft such as Joint Strike Fighter (JSF) must have PHM capabilities, Canadian initiatives also recognize the need to implement such schemes for future and legacy military and civil aerospace systems. With respect to four major technology areas of PHM, i.e., i) advanced sensors, ii) data analysis and fusion, iii) life consumption evaluation, and iv) predictions with reliability/risk assessment, there has been advanced technologies developed by NRC and others within Canada: - Aircraft/engine instrumentation and airborne data recording systems - Signal analysis and data fusion - On-line engine health monitoring - Physics based models for engine material failure modes and life prediction - Autonomic crack growth analysis for damage tolerance of engine components - Mission severity analysis algorithm - Probability, reliability and risk assessment This presentation reviews the above technologies in relevance to PHM, emphasizes the need to have physics based models and outlines the future R&D needs for integration and implementation of these technologies suitable for the advanced and legacy aircraft."

Jan 1, 2004

By K. E. Harley, M. J. Whiting, T. J. Sabin, E. M. Ryan, J. F. Watts

"Wire and Arc Additive Manufacturing (WAAM) has the potential to enable a very significant reduction in buy-to-fly ratio compared to conventional manufacturing through the ability to build near-net shape components. Components manufactured from AA 2319 by WAAM can exhibit significant levels of porosity. There is also a variation in the physical appearance of the surface deposit sometimes found on such components. This deposit is similar to those observed on aluminium joined by MIG and TIG welding processes. It has been suggested that both the bulk porosity and the surface deposit are caused by hydrocarbon-based lubricant on the feedstock wire. An established correlation between surface deposit and porosity would offer valuable insight into WAAM products and enable early interventions in quality control or process monitoring based on visual examination. The relationship between the nature of the surface deposit and porosity has been studied for AA 2319 WAAM components manufactured using different wire batches. Evidence is presented to support the assertion that (i) there does not appear to be a relationship between surface deposit coverage and porosity, (ii) batch-to-batch variability in feedstock wire affects porosity. This study has led to a better understanding of the cause of porosity in WAAM components.INTRODUCTION There is a high cost associated with conventional, subtractive manufacturing because of the high ‘buy-to-fly’ ratio, a measure of the initial material bought compared to the material found in the finished part (Allen, 2006; Yilmaz & Ulga, 2016). A typical aerospace product may have up to 90% of the purchased billet of forging machined away which is cost inefficient and high in material waste. Wire and Arc Additive Manufacturing (WAAM) has the potential to reduce costs and lead time. Robotically controlled weld torches rapidly deposit feedstock wire in layers to build large near-net shapes with mechanical properties similar to those of conventional manufactured parts (Sequeira Almedia & Williams, 2010; Martina et al., 2012; Ding et al., 2015; Williams et al., 2015). A high level of porosity variation has been observed in aluminium WAAM parts (Cong, Ding & Williams, 2014; Gu et al, 2016) which can result in a range of material properties (Rudy & Rupert, 1970). This leads to difficulties in regards to standardisation and qualification of process and parts. In order for WAAM to be used commercially, porosity will need to be understood, monitored and reduced to a reproducible acceptable level or eliminated."

Jan 1, 2018

"This document sets out the Exchange’s expectations and requirements for a valuation of mineral properties and outlines: the general purpose of valuation reports; guidelines respecting circumstances where the Exchange will require a valuation report; and valuation standards, guidelines and methods that are generally acceptable to the Exchange, 1. IntroductionThis Appendix sets out the Exchange's expectations and requirements for a valuation of mineral properties and outlines:(a) the general purpose of valuation reports;(b) guidelines respecting circumstances where the Exchange will require a valuation report; and(c) valuation standards, guidelines and methods that are generally acceptable to the Exchange.Mining industry standards and guidelines for valuations and valuation reports can be found in the Canadian Institute of Mining, Metallurgy and Petroleum Standards and Guidelines for Valuation of Mineral Properties (""CIMVal"") published in February, 2003 (www.cim.org). CIMVal consists of two parts, Standards and Guidelines. The Standards are mandatory and must be followed in order for a valuation to be CIMVal compliant. The Guidelines in CIMVal are not mandatory, but are strongly recommended.The Exchange requires that CIMVal Standards be used by Issuers and their professional advisors when preparing valuations and valuation reports on mineral properties. The CIMVal Guidelines should be followed by Issuers and their professional advisors in preparing valuation reports on mineral properties, with the exception that the valuation methods and guidelines under Section 4 Acceptable Valuation Methods and Guidelines below, must be followed."

Jan 1, 2003

By K. Soldenhoff

Mantra Resources Ltd is developing the Mkuju River project is southern Tanzania. The uranium deposit, hosted in ?Karoo? sandstone, is surface outcropping with the majority of uranium mineralisation occurring in the finer clay component of the ore. A flowsheet, consisting of ore beneficiation, acid leaching, RIP uranium recovery and direct precipitation of the uranium product, was developed and successfully demonstrated in continuous mini-plant operations at ANSTO. The selected flowsheet overcomes the difficult slurry rheology, arising from the clay component of the ore, by eliminating the need for a CCD plant. The RIP process was found to contribute to a high uranium extraction, by eliminating ?preg-robbing?, at a relatively low acid addition in leach, with the potential to eliminate ferric ion and oxidant additions.

Aug 1, 2010

By Nicolas Gatelier, Sophie Laurent, Thierry You

Hard-rock caverns for hydrocarbon storage are a very particular type of underground facility controlled not only by local administrative and regulatory constraints that can be very specific, but also by the possible risks of geotechnical or geomechanical failure. Each such facility throughout the world is a prototype that needs to be adapted to very different site conditions. The straight forward application of design methodologies from relatively similar fields (mines, tunnels) can be very useful, but risks holding back the scientific and technical improvements needed by an engineering industry in full development. Here we look at various case histories and at problems that have been raised where recent attempts at standardization would appear to have been ill adapted, and where storage designers, through experience and judgment, may still provide innovative engineering solutions.

Jan 1, 2015

By John E. Udd

"In this paper the author presents the results of the 1992 CIM survey of graduates in minerals and technology programs in Canadian post-secondary institutions. As usual, the trends are out-of phase with the economic state of the industry. People who chose a minerals career in the prosperous days of the late 1980sare now entering a labour market in recession.The cyclical nature of enrollments is illustrated in a series of figures showing the trends since the CIM survey Wa5 begun in 1956 (and even earlier for mining engineering).In the survey, the respondents were asked to provide comments on their perceptions of the problems specific to minerals education in Canada. The large number of responses have led the author to the conclusions and recommendations given in the final part of the paper."

Jan 1, 1993

By Alessandro Navarra

Discrete event simulation provides a computational framework in which the use of smelting equipment can be analyzed and optimized, leading to the development of alternative modes of operation. Much of the complexity of copper and nickel smelters is centered on the converter aisle. These converters operate in parallel, produce batches, and set the tempo for the downstream operations. In practice, smelter staff schedule daily operations to coordinate the smelting furnaces and converters with downstream operations. Thus, a realistic simulation of smelter operations, over hundreds of days, should incorporate converter scheduling algorithms as presented in this paper.

Jan 1, 2014

By P. Hr?enjak

Two groups of methods are usually used in design procedures of underground excavation of dimension stone: the analytical and numerical methods of analysis. In all of these methods the in situ rock mass strength represents the main problem. This is due to massive rocks in dimension stone deposits, consisting of large blocks of rock separated with particular discontinuities, for which the Hoek-Brown empirical criterion, developed for jointed rock masses, cannot be realistically used to estimate rock mass strength, especially for a particular block of rock mass or a particular pillar. On the basis of the regular underground excavation process of dimension stone by separating blocks with the flat jack application, we developed the in situ flexural strength testing method. We carried out numerical analyses and evaluation of uncertainty of measurement in order to validate the in situ flexural strength testing method. On the basis of very good validation results, as well as results of the in situ flexural strength testing of exploitable layers on the ?Kanfanar? quarry, we introduced a new coefficient of reduction, which can be used for correction of other strength parameters determined by laboratory testing for obtaining a realistic value of rock mass strength.

Aug 1, 2013

By Zhigao Xu, Ruan Chi, Zhenyue Zhang, Yaoyang Ruan, Zhengyan He

Weathered crust elution-deposited rare earth ore is a specific rare earth resource in China that is rich in middle and heavy rare earths. From surface to bottom, the weathered crust elution-deposit rare earth ores can be divided into humic layer, completely weathered layer, partly weathered layer, and bedrock. The exchangeable rare earth ions mainly exist in the completely weathered layer and partly weathered layer, and the exchangeable aluminum ions mainly exist in the humic layer. A novel solution injection method for use in the in-situ leaching technology of weathered crust elution-deposit rare earth ores was put forward based on the different distributions of RE3+ and Al3+ in the four layers. Avoiding the humic layer, only the completely weathered layer and partly weathered layer were leached by controlling the height of the leaching solution liquid level. In this way aluminum, the primary impurity in the RE leaching solution, can be decreased and the purity of the RE product can be improved. Meanwhile, the choices of available leaching reagents were broadened and the possibility of landslide disasters could be reduced.

Jan 1, 2014

By F. Romero

In the last four years, Compañia Minera Doña Ines de Collahuasi has been working in the application of advanced multivariate statistical techniques for the improvement of the metallurgical processes. In this paper the main conclusions for the application of multivariable analysis to the EW process are presented; including the identification of (target) process patterns according to throughput and quality criteria. Based on the process patterns, process variables hierarchies were identified by selecting the most influential ones, as well as to identify and isolate the root causes of pattern deviations and sub-standard operating conditions, cause-effect relationships were established, leading to the definition of process policies and controls to give early corrections to potential failures. The analysis was focused on cathode quality, specifically in its sulfur content, using an empirical model based on those variables that from a phenomenological and statistical stand point appeared to be the most influencing ones.

Jan 1, 2007

By S. F. Dudka, T. Dang, M. L. Wong

Abstract - The Nui Phao W-F-Cu-Au-Bi deposit is located in one of the poorest regions of northern Vietnam. The deposit is currently undergoing a pre-feasibility study by Tiberon Minerals Ltd., with a view to developing what would be the largest WO3 mine and one of the five largest fluorite mines in the world. The project is being planned in close compliance with World Bank and national guidelines for environmental and social protection. Development of the mine is anticipated to bring the following benefits: remediation of serious pre-existing environmental conditions (natural and anthropogenic heavy metal contamination and acid rock drainage); provision of employment and training, and thereby wealth, to local communities; significant tax and royalty payments to government, which will be reinvested as social spending; and development of municipal and industrial infrastructure to build sustainable post-mining communities. The role of governments at all levels is critical in guiding and facilitating this process. This paper was written prior to development of the mine, and relays the intentions of the developers. Future studies will be needed to evaluate the degree of attainment of sustainable development objectives, both during mine operation and after closure.

Jan 1, 2003

Strips of AA6111 automotive alloy were cast on a horizontal single belt strip casting simulator, Pure copper and carbon steels substrates plasma sprayed with different coatings for improving the strip surface quality, were used as chill moulds, Experimental studies revealed that a graphite coating provided the greatest benefit in achieving good surface quality. The interfacial heat fluxes during solidification of AA6111 strip were calculated by the IHCP method (Inverse Heat Conduction Problem). Temperature variations and cooling rates within the strips were then calculated through numerical simulations based on the time-dependent heat fluxes obtained by IHCP, The effects of casting parameters, including casting temperature and strip thickness, on interfacial heat fluxes, cooling rates and microstructures, were investigated, Although the maximum interfacial heat fluxes on the chill copper substrate were much higher than the results obtained from the steel substrates, the solidification times of the melts were mainly determined by strip thickness. Very fine equi-axed grains were obtained for both 1.2mm and 2.5mm thick strips thanks to the rapid extraction of heat, and effective grain refinement.

Jan 1, 2005

By T. Negeri, M. Boisclair

"A hybrid process consisting of flotation and magnetic separation has been developed to concentrate multi-phase rare earth minerals associated with a carbonatite ore that contains a significant amount of niobium. Fine grinding to a d80 of <65 microns was required to obtain acceptable separation of 92% of the contained total rare earth oxide (TREO) and niobium in half the feed mass. Whereas it was possible to obtain 85% of TREO in 28% of the feed mass through staged cleaning, it was demonstrated that at least 87% and 85% recoveries of TREO and Nb respectively could be achieved in 16% of the feed if the rougher-scavenger concentrates were calcined, quenched, reground to <25 µm and then magnetically upgraded. The paper discusses the overall concept of the flowsheet and the experimental strategies that led to this progress. INTRODUCTIONOut of the approximately 250 minerals known to contain rare earth elements (REEs), only about 60 of them contain REEs in significant amounts. Over 95% of the world’s rare earth oxides (REOs) are believed to occur in the form of three minerals (Pradip & Fuerstenau, 1991) namely bastnaesite (Ce,La,Y)CO3F, monazite (Ce,La,Nd,Th)PO4 and xenotime Y(PO)4. An estimated 51.4% of global REO resources are hosted by carbonatite deposits with the same three minerals as major constituents (Weng et. al., 2015). Any one of the REEs or commonly all of them can be found in these minerals (Ravnaas, 2010). As the demand for critical REEs increases due to the ever increasing applications in advanced technologies, many deposits containing other forms of REE minerals will have to be developed. REE minerals are extensively dispersed and intergrown with several oxides, silicates, carbonates, and phosphate minerals. Consequently it is possible to liberate them only at fine grinding and is thus difficult to separate and produce high grade rare earth mineral concentrates. Most of these minerals contain other important elements such as tantalum (Ta), niobium (Nb), uranium (U), and thorium (Th) in varied quantities. REE minerals in the same ore may exist as carbonates, fluorocarbonates, niobates, silicates, phosphates etc. in association with gangue minerals belonging to different mineralogical groups."

Jan 1, 2016

By C. Larsen, R. A. Walker, A. Voth, C. Daoust

"The 3000 t/d mill at Hernia Gold Mines Inc. was commissioned in March, 1985. By Canadian standards the concentrator is highly automated, however, unlike the retrofit systems in many other plants, the Hernia process control system was installed during plant construction. This paper describes the Hernia control system beginning with system development (justification, architecture, start up, etc.), proceeding to current applications (crushing, grinding, leaching, etc.) and finally discusses some of the short term objectives for system improvement.INTRODUCTIONThe Hernia Gold Mines Inc. operation is located in the Marathon area of Northwestern Ontario. Controlled by Noranda Minerals Inc. (50.1 %), the cost of bringing the mine into production was nearly $300 million. A unique feature of the mine development was the extraordinarily short elapsed time of three years from Noranda's initial involvement to the start of milling operations. Additional background information on this project can be found in the trade literature (e.g. Tinter (1986). Scales (1987).)The Hernia concentrator is designed to process 3000 tpd of ore and commenced operation in March, 1985. Figure 1 provides a general plant flowsheet indicating the major circuits. Typical annual production statistics are included on the figure and these have been extrapolated from the available 1987 year-to-date data. Larsen and Tessier (1986) have previously described the operational aspects of the mill.In a metaphorical sense, the Hernia concentrator is like the traditional bride, ""wearing something old (e.g. the cyanide leach process), something new (e.g. a plant wide digital control system installed during construction), something borrowed (e.g. crushers from Gaspe) and something blue (e.g. the cladding on the surface buildings). While the prospect of fully undressing this bride is of considerable interest, here we choose to focus on something new. In particular, we choose to examine the process control system in some detail since Hernia is one of Canada's more highly autcmated gold mills. The control system is of interest because it has received suostantial credit for maximizing metal production and minimizing operating costs. With reference to the latter, it is worthy of note that Hem lo reports recent operating costs of less than $100 U.S./oz."

Jan 1, 1988

By K. V. Konigsmann

"The mill at Mattagami Lake Mines treats 3,850 tons per day. The mill feed is a heavy sulphide ore. It is composed ofPyrite & Pyrrhotite - 40%Marmatite - 17%Chalcopyrite - 2%Magnetite - 10%Talc and other Silicates - 31%The sulphides are intimately associated with each other and often finely disseminated throughout the siliceous gangue. An abundance of middling particles exist in the circuit and a delicate balance has to be maintained between concentrate grades and metal recoveries.The metal content of the mill feed fluctuates between 0.4 to 0.7% for copper and 6 to 13% for zinc.The flow sheet of the concentrator is shown in Figure 1.Eight sample streams have been selected for on-stream analysis, namely1. Copper Concentrate 2. Copper Cln Tailings 3. Copper Tailings 4. Zinc Concentrate5. Zinc Rgh Concentrate6. Zinc Cln Tailings7. Zinc Rgh Tailings8. Flotation TailingsThe mill feed is not being analysed. Only a very coarse sample could be obtained which would be difficult to pump, and the fluctuations in the copper content are too small in absolute terms to have much of a bearing on circuit operations."

Jan 1, 1969

By Selvia Tourn, Liliana Castro

"Abstract - Argentina, a large country with an important agriculture industry, needs an ever-increasing amount of phosphorus and potassium, as essential elements for plant growth. Current requirements are met from imports, but potential resources exist in Argentina. For example, several phosphatic occurrences are known in paleo-marine basins, the most significant of which are in Tertiary units in Patagonia. In addition, two types of potassium deposits are also known in Argentina: evaporite deposits in the Neuquén Basin at depths of 750 m to 1500 m contain 22 to 25 wt% K2O equivalent; and glauconitic sandstone containing about 6 wt% K2O has been identified in Patagonia.Several experiments were undertaken to test unprocessed phosphate rocks as slow-release, direct-application fertilizers, with good results. In addition, it is proposed that direct application of glauconitic sands would provide an efficient and economic alternative source of potassium. Tests with glauconite samples are still in progress. The existence of both phosphate and glauconitic rocks in Patagonia suggests that development of an extractive industry for these materials would not only help Argentina approach self-sufficiency in fertilizer usage, but also assist in the socio-economic development of this region."

Jan 1, 2003

By Gene O. Cowie

"Zinc, which once enjoyed an unchallenged position in the field of decorative applications, has lost a substantial share of its markets to other materials, particularly plastics. This turn of events has led the zinc industry to explore new market areas, particularly those applications where the engineering properties of zinc can be utilized. This paper gives an overview of the zinc industry&apos;s efforts to develop the data base and product development technology which have enabled zinc alloys to emerge as engineering materials. It also indicates those areas in which the research facilities of the zinc industry must be employed to ensure that zinc alloys keep pace with developments in competitive materials and processes.The Materials RevolutionThe development and utilization of new materials and manufacturing processes progressed for centuries by evolution. Recently it erupted into a revolution, which may become as significant as the industrial revolution. The materials revolution has impacted upon many industries, but none has been affected more traumatically than the North American automotive industry. The plight of that industry is of great importance to us because their problems have, to a great degree, become problems to the zinc industry.Much of the impetus behind the automotive trauma came from the battery of motor vehicle regulations promulgated by the United States government in the 1970s. These regulations required that the efficiency of passenger cars, in terms of miles per gallon, be approximately doubled in ten years. In view of the fact that major changes in the automotive world require three years of lead time to implement, the industry was left with only seven years to perform the task. The automotive industry was simultaneously required to make progress in other areas, such as reduced emissions, reduced cost of repairs and increased levels of occupant safety. These added demands not only diverted some of the available resources away from efficiency goals, they often ran in direct conflict. For example, when you are required to provide a front bumper which will absorb the energy of a 5-mile -per-hour barrier collision, you must add both hardware and structure to the vehicle. This adds weight, and increased weight reduces miles per gallon."

Jan 1, 1983

"In 2008, the Committee for Mineral Reserves and International Reporting Standards (CRIRSCO) and the Russian State Commission on Mineral Reserves (GKZ) entered into an agreement leading towards harmonization of Russian and international minerals reporting systems. The purpose of the protocol is to define an agreed method by which mineral resources and reserves, reported by companies in Russia according to the current Russian classification system, can be expressed in terms that are comparable to the CRIRSCO reporting codes in Russia and elsewhere."

Jan 1, 2003

By Y. Wang

In this paper, the tribological and electrochemical corrosion properties of Al2O3/polymer nanocomposite coatings were studied using a micro-hardness test, a single-pass scratch test, an abrasive-wear test, and finally an electrochemical technique such as potentiodynamic polarization measurement, The coatings containing Al2O3 nanoparticles showed improvement in scratch and abrasive resistance compared with polymer coatings; this improvement is attributed to the dispersion hardening of Al2O3 nanoparticles in polymer coatings, Corrosion test results showed that the embedded Al2O3 nanoparticles in the polymer matrix do not sacrifice the corrosion resistance of the polymer itself.

Jan 1, 2005

By Z. Manafi

Bioleaching of a copper sulfide ore containing "activated pyrite", using a mixed culture of mesophilic bacteria, was studied. This type of copper ore had been found unsuitable for flotation because it produces a concentrate containing relatively high iron concentrations and, therefore, a low copper grade. Microscopic observations showed that pyrite particles had been activated by the formation of a thin film of chalcocite. Hence, a bioleaching process was considered as an alternative to treat this ore. Following shake flask and acid consumption tests, column tests of the crushed ore (75% -12.5 mm) were initiated and the effects of culture medium, agglomeration, and irrigation type on copper recovery were studied. The results showed that all the columns containing bacteria had copper recoveries around 90% compared to the abiotic control column with a recovery of 50%. It was concluded that bioleaching could be successfully utilized to process copper ores containing activated pyrite.

Jan 1, 2007