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By A. J. Antony Chettupuzha

Electronic Product and Process Management [EPPM] systems provide the capability to establish and map information flow between different parties in a construction project as well as model project processes. Much of the information relating to processes and their structure, the actors that operate them, and the data associated with each instance of a process is encapsulated within workflows. The wealth of information contained in an EPPM system can be exploited to extract knowledge that can provide significant cost benefits to construction companies. Workflows provide an ideal medium for the capture of knowledge over the course of a project lifecycle. We demonstrate how this knowledge may then be used to analyze workflows and determine metrics that establish the suitability of workflows to construction processes. We present a conceptual approach to measure the performance of a workflow, its constituent components and evolution, which may be used to lay the foundation for establishing paragon workflows suited to classes of construction activities.

Aug 1, 2013

By G. S. Hume

"THERE HAS BEEN a marked growth in the petroleum industry in Canada since the end of the war. The rate of growth in the demand for oil products has exceeded that in United States, although the per capita consumption is still less. Estimates of the consumption of petroleum and petroleum products in Canada in 1951 are approximately 154,000,000 barrels, which is slightly more than 11 •barrels per capita, whereas the estimated consumption in United States for the same period, according to World Petroleum, is placed at 2,619,- 970,000 barrels. This, on the basis of a population of 154,000,000, would be equivalent to 17 barrels per capita. The increase in consumption of the petroleum and products is world wide. World production in 1951 has been estimated (Oil and Gas Journal) at 11,700,000 barrels a day or more than 41;4, billion barrels for the year. United States production increased 13.7 per cent to 6,143,000 •barrels a day and Canada'.s ,, total production increased about 65 per cent from a total of 29,091,235 •barrels in 1950 to an estimated (Dominion Bureau of Statistics) 48,096,800 barrels in 1951.The trend to use increased amounts of petroleum and petroleum products, particularly in the United States and Canada, has also been supplemented by increased use of natural gas. The rate of expansion of the consumption of natural gas in United States in the past few years has been very rapid, increasing from 2,600 billion cubic feet in 1940 to 5,975 billion in 1950, with the proven reserves in the same period increasing from 85,000 billion to 186,000 billion cubic feet."

Jan 1, 1952

By Russell Spry

THE cyanide plant of the Cariboo Gold Quartz Mining Company, Limited, at Wells, B.C:, in the Barkerville section of the Cariboo mining division, was erected during the latter part of 1932 and placed in operation in January, 1933. The initial capacity of the plant was about 50 tons daily. This was increased to 100 tons at the end of 1934 and stepped-up to 150 tons in September, 1935. It is expected that further plant extensions, for milling a total of 200 tons daily, will be required during the early part of 1936. Recent additions to the mill have been so planned as to permit ready expansion to 275 tons daily when underground development warrants the milling of this tonnage. It is the purpose of this paper to outline briefly the steps taken to bring the plant to its present capacity and to comment on possibilities for further plant expansion. The gold in Cariboo Gold Quartz ore occurs as free gold in the quartz and on pyrite surfaces. Some of it is very finely divided, specks l/10,000 inch having been observed microscopically, according to Dr. G. Hanson. In addition to pyrite, which comprises probably 15 to 20 per cent of the mill feed, galena and sphalerite are present, with small amounts of arseno-pyrite and chalcopyrite. Sulphobismuthites-chiviatite, galenobismutite, cosalite, etc.-occur more or less frequently in certain sections of the mine. Following tests on Cariboo ore by the Mines Branch, Department of Mines, at Ottawa, treatment of the ore by straigh t cyanidation was recommended and a 50-ton plant employing continuous counter-current decantation was erected. This plant was built as a pilot mill, the intention being to erect a larger mill after metallurgical treatment had proved successful over an extended period. This original installation, however, has been enlarged and retained as an operating unit, additional equipment being added to it as capacity increases have been required.

Jan 1, 1936

By Li Qihou, Liu Zhihong, Liu Zhiyong, Yao Wei

Black copper sludge, which mainly contains copper, arsenic and a little antimony, bismuth, selenium, tellurium, is an important recyclable secondary resource. In this paper, selective removal of arsenic from black copper sludge by alkaline oxidative pressure leaching was studied. The influences of alkali concentration, leaching time, leaching temperature, oxygen pressure, liquid-solid ratio and other variables on the leaching rate of arsenic, copper and tellurium were investigated. The results were as follows: when the leaching process was conducted at initial alkali concentration of 1mol/L, liquid-solid ratio of 10, stirring rate of 500r/min, leaching temperature of 140°C for 5 h and oxygen pressure of 2.5MPa, the leaching rates of arsenic and tellurium were 85.43% and 59.7% respectively, and copper, antimony, bismuth were not leached. Hence, arsenic has been removed effectively from black copper sludge, while the valuable metals such as copper, antimony and bismuth remained in the residue that can be further recovered easily. INTRODUCTION Black copper sludge is a byproduct in the purification process of copper electrolyte. Arsenic, antimony and bismuth are major harmful impurities in copper electrolytic refining system. The accumulation of these impurities will cause adverse effects, such as the increase of electrolyte resistance and power consumption and deterioration of cathode copper quality (Wang, Liu, & Zhang, 2001). Hence, electrolyte purification is an essential part of the electrolysis process (Liang, Chen, & Guo, 2009). Electrolyte purification methods include electrowinning (Davenport, King, Schlesinger, & Biswas, 2002), solvent extraction (Navarro, Simpson, & Alguacil, 1999), ion exchange (Arroyo et al., 2017), coprecipitation (Wang et al., 2003, 2018; Xiao et al., 2007; Xiao, Cao, Mao, Shen, & Ren, 2014), activated carbon adsorption (Navarro & Alguacil, 2002), electrodialysis (Cifuentes et al., 2015), redox process (Zhou, Peng, Zheng, Ma, & Cui, 2011; Peng, Zheng, Zhou, & Chen, 2012; Zheng, Peng, Ke, & Chen, 2013), among which the electrowinning method is simple in operation and effective in impurities removal, making it the main process for current electrolyte purification. Some copper ions can react with harmful impurities to form complex black copper sludge by controlling the operation conditions of electrowinning process. Based on the estimated data provide by Davenport et al. (2002), an annual output of 400,000 tons cathode copper could produce 432-2168 tons of black copper sludge by electrowinning method. Black copper sludge contains 30~50% copper, 15~30% arsenic and a small amount of rare elements such as selenium and tellurium. Thus, recovery of valuable metals can bring huge economic interests. Moreover, arsenic in these sludges could cause significant environmental pollution. Therefore, effective removal of arsenic from these sludges is urgent and significant.

Jan 1, 2019

By G. C. Bateman

Canada is a very large country with a small population which is growing very slowly. We have great natural resources, but with our limited population we are continually looking afield for new capital to develop these resources. Our mining areas are among the most important fields offering opportunities for new capital and because of the wide-spread appeal which mining makes this industry commands a great deal of attention. While we are glad to see new capital from any source, we welcome it particularly from Great Britain, for, although we offer equal opportunities to the nationals of any country we would be glad to see the development of our natural resources financed as far as possible within the Empire. However, when we invite ne capital we must accept certain responsibilities, and while we have opportunities to offer, we should ask ourselves how these opportunities are taken advantage of and what sort of treatment the foreign investor receives.

Jan 1, 1925

By M. Fafard, D. Picard, J. -F. Bilodeau, G. Soucy

To simulate adequately the behaviour of a Hall-Heroult electrolysis cell, a finite element model must take into account the properties of each material. However, it has some lacking knowledge on the mechanical behaviour of materials, like the long-term visco-elastic (creep/relaxation) behaviour of cathode. A three-dimensional model is then proposed in this paper and will be ready to be implemented in the finite element code FESh++. The model was developed using the three-dimensional model based on thermodynamic of irreversible processes where the choice of the internal variables is based on a phenomenological approach. All parameters of the model are represented by constant constitutive tensors and the temperature and chemical dependencies are taking into account through scalar functions multiplying the constant constitutive tensor. The goal of the first part of this project was to determine the parameters of the threedimensional visco-elastic model at the reference state (virgin material at ambient temperature) of three different cathode materials. This paper presents the theoretical model and the results of creep tests at ambient temperature for the semi-graphitic carbon cathode.

Jan 1, 2006

By C. Jay Hodgson, Adrienne C. L. Larocque

Abstract -The Mobrun VMS deposit in northwestern Quebec does not fit the classic Noranda­ type model, but exhibits characteristics more consistent with a Mattabi-type deposit. The orebodies are underlain by fragmental volcanic rocks indicative of explosive volcanism in shallow water. Felsic volcanic rocks are more abundant than mafic rocks. Alteration assemblages comprise chlorite, carbonate, sericite, and quartz. Broad semi-conformable alteration occurs high in the footwall to the 1100 lens. Mobrun occurs higher in the stratigraphic sequence than most of the other deposits in the Noranda camp. In this part of the stratigraphy, zones of pervasive carbonatization may be more useful guides for exploration than zones of silicification.

Jan 1, 1993

By J. Severin

Surface mining operations are increasingly involving the design and development of deeper and larger open pits, often with plans to transition into underground mass mining operations. Experiences at the Palabora Mine in South Africa demonstrate the complex interactions between underground workings and the steep slopes above that may lead to slope movements that potentially pose safety and economic concerns. To properly assess the rock mass response to these interactions for planning of future developments, understanding the controlling influence of geological and geomechanical structures is crucial. Preliminary results are presented from a detailed review of historical slope monitoring data from the Palabora Mine, before and after the initiation of block caving 400-m beneath a 800-m deep pit. This paper demonstrates that a detailed analysis of geology and monitoring data can be used to better understand the kinematic controls of complex rock slope displacements and interactions between open pits and underground mines. This investigative treatment of the monitoring data is important in understanding the failure mechanisms prior to undertaking sophisticated 3-D numerical models.

May 1, 2009

By S McQuitty

The metallurgical treatment of Falconbridge ore re-quires an extremely fine grind of the pyrrhotite portion ? for maximum liberation and recovery of nickel. This paper describes the operation of a grate discharge pebble mill in closed circuit with cyclones regrinding 25 to 30 tons per hour of sulphides to approximately 90 per cent minus 325 mesh. The consumption of the screened ore grinding medium is of the order of 2.5 pounds per kw.-hour, or less than 1 per cent of the tonnage of re-ground sulphides. IN RECENT years, there has been a considerable interest in pebble grinding in the uranium industry, and a number of installations have appeared. However, the use of sulphide ore pebbles as a grinding medium has so far been relatively limited. There has also been some question as to their suitability for the very fine grinding of sulphide concentrates. This paper describes the preliminary results of a commercial operation involving the

Jan 1, 1964

By J. Gillies

"Those of you who were at last years C.M.P. meeting are aware there was discussion at that meeting concerning the best method of assisting the assayers of metal mines to exchange new ideas and methods of assaying. The opportunity to advise you of what came of that discussion is very much appreciated.There are several societies, including the Chemical Institute of Canada, the Spectroscopy Society and others that could be of some assistance to assayers. However, since these societies cover a rather broad field and not many mine assayers have the opportunity to attend their meetings, it was felt that an organization oriented to the specific needs of the mine assayers would be of more value to them.Several years ago an attempt was made to hold meetings for the benefit of assayers in conjunction with the Conference of Metallurgists held each year by the Metallurgical Society of the C .I.M.M. This did not work because very few of the mine assayers attended the meetings.With the very evident success of the type of meetings the C.M.P. have and the excellent groundwork done by your secretary, Mr. Stevens, in talking about this to mine management and assayers at many mines across the country, it was decided to hold a meeting at Noranda on October 8 to discuss how best we could help ourselves solve our problems.For the initial meeting it was felt that perhaps it would be better to start with a smaller group, so invitations were sent to mines in Ontario and Quebec that were geographically fairly close to Noranda."

Jan 1, 1970

By K. R. Nichol

The author points out that corrosion works 24 hours a day, every day. It is an economic reality that the cost of corrosion is inevitable and that its cost should be incurred in the least expensive way. An economic evaluation technique to properly assess its relative impact is the Discounted Cash Flow Method. Various remedial and corrosion control measures are available and these, when coupled with a planned corrosion control program, help reduce the cost of corrosion.

Jan 1, 1973

By M. N. Collison

"In 1960, with the opening of the Chisel Lake mine near Snow Lake, Manitoba, the Hudson Bay Mining and Smelting Co., Limited, commenced a new phase in their mining operation -that of bringing ore to Flin Flon over 100 miles of railroad.The schedule of operations required to accomplish this, together with an outline of some of the problems of handling ore at 40° and 50,0 below zero, are discussed. The facilities required to thaw and unload from twenty to fifty cars per working day are also described."

Jan 1, 1966

By J. C. Loretto, H. A. Simons

The paper discusses how, in the routine testing of ores, insufficient communication between the laboratory and the design personnel can lead to misunderstanding or misinterpretation of test results and consequent design errors. A number of examples are given together with suggested modified interpretations and the resulting dollar savings indicated by these new interpretations.

Jan 1, 1972

By Yan-Jun Shen

The rock mass classification system, BQ (basic quality), is the only national system that is suitable to most kinds of rock engineering in China. It uses two main aspects of the rock mass, the intact uniaxial compressive strength (UCS) and the rock intactness index (KV), to obtain the rock mass BQ. The index KV could be measured by the acoustic wave method. However, because this method is an indirect approach to characterize the rock mass structure, misfits often occur between the test results and the actual rock mass characteristics. Therefore, a new parameter KGSI expressed by the geological strength index is proposed to replace the original KV, and a new method is presented to express the value of BQ as a function of the UCS and the KGSI. Then, the underground excavations at five hydropower stations were chosen as examples to study the relationship between the revised BQ and the each of the international systems (RMR, Q or RMi). In addition, the applicability of the RMR, Q, or RMi system is discussed for China?s rock characteristics and geological conditions, and suggestions are given for improving the revised BQ system.

Aug 1, 2013

By Loui Geoffroy, Philippe Gaultier, Martin Piotte, Claude Coache, André Drouin

"Automatic driving at high speed of an underground truck was tested at Brunswick mine in September 1995. Modifications to the truck included: a remote interface to control actuators, front and back video cameras to follow a roof mounted optical guide and proportional hydraulic controls on the steering.The mathematical model of the hydraulic system was adjusted using least square regression. The steering data, used in calculating the regression parameters, were acquired from the moving truck. The automatic steering control used three measured variables: lateral deviation, angular deviation and steering angle. Lateral deviations are obtained using the cameras, which are in continuous view of the guide, while steering angles are acquired from an extensiometer placed at the articulation point of the vehicle. Gain scheduling was used to compensate for vehicle speed and available hydraulic flow. Non-linear characteristics of the modeled hydraulic system were offset using open loop compensation.Speeds up to 23 km/h in forward direction and 13 km/h in reverse were achieved deviaduring continuous testing along one of the mine’s production drifts. Proportional steering was essential in achieving high speeds, as it enabled more precise positioning of the vehicle’s steering direction while reducing the abuses on cylinder and cylinder pins via diminished oscillations about the optical guide at high speeds."

Jan 1, 1997

By H. Aminian

Gold powders have many important industrial applications. In this paper the available processes for the preparation of gold nano and micron sized powders are described. The attention has been given to hydrometallurgy route and the recent works and achievements in controlling the powder morphology are highlighted.

Jan 1, 2011

By John D. Carriere, Jean Leung, Daniel. Laguitton, Michael .. J. Burrows

"The objective of this expert system application in a copper-zinc concentrator, is to increase the availability of assay data through substitution for erroneous data. The assay data is used by the Operations personnel and automatic process control strategies to control flotation circuit performance. Two online X-ray fluorescence analysis systems analyze 24 streams across four divisions to provide the required data. Data availability of individual streams average 90% while the resulting circuit availabilities are 70%. The unavailability of correct data results from mechanical, X-ray or process problems. The erroneous data can be identified by process experts using knowledge relating stream interdependencies and historical process behaviour. An expert system was devised to provide real time identification of erroneous data and substitute for that data with the ultimate aim of improving metallurgical response by both the operator and automatic control systems.The paper discusses the early development work and architecture of the knowledge base designed using Neuron Data's expert shell NEXPERT.INTRODUCTIONThis paper describes the early development of an expert system (ES) prototype at the Kidd Creek concentrator. The project is a joint undertaking of the Kidd Creek Division of Falconbridge Limited and CANMET. Kidd Creek entered into the project to apply heuristic rules to the XRF assay data to improve the metallurgical control of the flotation process by increasing availability of analysis data. This project provided a problem of suitable size and future expandability while making use of a wide base of in-house expertise and experience. Another important benefit is the introduction of expert system technology to the site providing tools and experience for future system selection and technology application. CANMET has an on-going interest in assessing various aspects of ES technology (hardware, software, knowledge engineering, integration) while addressing problems in process operations that could most readily benefit from the technique. CANMET's role in the project was to provide project assistance, financial support, substitution algorithm assistance and software for data substitution. The knowledge bases (rules) have now been completed and are to be tested in the online environment."

Jan 1, 1989

By Matthew Blecha

The Tribag copper deposit is one of the rare examples of mineralized breccias in the Canadian Shield. The breccia is a pipe-like body, and consists of granitic, diabasic and volcanic fragments embedded in a vuggy, quartz-carbonate matrix. The mineralization is essentially chalcopyrite and pyrite, with minor molybdenite, sphalerite, galena and other sulphides. The main ore zone is saddle-like in shape, and is enveloped in a zone of chloritization, sericitization and clay-mineral alteration. It is suggested that the breccia is of the diatreme type. Introduction T HIS paper is based on eighteen months of field work, including surface and underground geological mapping and core logging, and on the survey of relevant literature. No significant amount of laboratory work has been done as yet. Location and Access The Tribag Batchawana property is located 40 miles north of Sault Ste. Marie, Ontario, about 10 miles east of Lake Superior. A 17-mile, all-weather road connects the property to the Trans-Canada highway to the south, and 4 miles of a 12-mile road remain to be completed to link it to the Algoma Central Railway to the northeast.

Jan 1, 1965

By Lin Li, Ahmad Ghahremaninezhad

"In this paper, the electrochemical behavior of ferric and ferrous couple on the pyrite surface was studied by application of the chronoamperometry technique in an acidic solution at room temperatures and atmospheric pressure. The effects of the pyrite origin, ferric and ferrous ions concentration on the electron transfer kinetics of Fe3+/Fe2+ reaction were probed. Tafel behavior of all the test conditions were developed. The results showed that the ferric-ferrous reaction on pyrite electrodes with different origins have a common mechanism, despite different reaction kinetics. The exchange current densities of the redox reaction have the same magnitude of about 10-5 A·cm-2, which is far lower than the value reported for the gold and platinum electrodes, but larger than that of the chalcopyrite electrode. The cathodic transfer coefficients are between 0.4 and 0.5, while the anodic transfer coefficients appear unusual with the lowest value being 0.23. It was also demonstrated that an increase of one order of magnitude of iron concentration has no clear effect on the exchange current density and cathodic transfer coefficients of Fe3+/Fe2+ redox reaction.INTRODUCTIONPyrite, FeS2, is mostly considered as a gangue mineral which frequently coexists with valuable minerals and metals, such as gold, copper and nickel. Its separation from valuable minerals can be a costly process (Chandra & Gerson, 2010). In refractory gold ores, the fine gold particles are locked inside the pyrite structure. Oxidative leaching of pyrite is a hydrometallurgical method to destroy the structure of pyrite and expose the fine gold particles to the cyanide solution in the downstream cyanidation circuit. Pyrite oxidative leaching can be achieved by oxidation of pyrite via oxygen and ferric ion(McKibben & Barnes, 1986). In fact, pyrite oxidation by oxygen and ferric is a significant source of acid mine drainage(AMD), which adversely causes serious environmental problems(V. P. Evangelou, 1995).The pyrite oxidation mechanism is accomplished in three consecutive steps: (i) pyrite is oxidized by oxygen and ferrous ion formation (Eq. 1); (ii) ferrous oxidation by oxygen and ferric ion formation (Eq. 2); (iii) pyrite oxidation by means of ferric ions (Eq. 3). Hence, both oxygen and ferric participate in the pyrite oxidation process (Moses & Herman, 1991):"

Jan 1, 2016

By P. Cavanagh

Summary This paper discusses the fundamental principles which allow the development of a new method for studying the deformation and failure of metals in terms of 'internal microstrains'. Internal microstrains mechanical and magnetic properties are defined and their influence on of metals is outlined. A research programme at present in progress will determine whether magnetic measurements of internal microstrains give sufficiently accurate values for predicting the performance of metals under service conditions. These magnetic test techniques are also being used to detect the beginning of plastic deformation and to trace the development of deformation processes and failure. Results of the experimental work in each field will be published. Introduction Any attempts are being made to develop a complete theory embracing the mechanical behaviour of metals. In spite of the amount of experimental data available, the theoretical approach is rather difficult, since most of the mechanical properties of a metal are determined by deviations from the pure chemical composition or the perfect crystal. Both types of deviation are difficult to reproduce experimentally and to describe theoretically. In general, there are three main avenues of approach to the problem being followed today.

Jan 1, 1950