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By S. Espley, G. Tan

"Inco's Little Stobie Mine is a low-grade nickel operation producing approximately 4()()() tons per day. Backfill has never been an economical option at the mine; therefore, the only viable type of mining in the upper zones has been by sub-level cave. This mining method allows for the draw-down of a rock cover into the empty stopes to provide stability to the over-all rock mass. In the lower areas of the mine, bulk blasthole mining methods have taken place, without rock fill, resulting in extremely large open stopes. As the mine reaches its final stage of recovery, it is inevitable that the hangingwall of the large voids will undergo tensile failure via spoiling.This paper deals with the collaborating efforts of Inco's Rock Mechanics group and the Little Stobie mining operations toward the successful recovery of the ore zone remnants such that the inevitable failure, and time of failure, of the rock mass is ""controlled"". Within the mining scheme, several key requirements had to be met to satisfy the operations: (1) production rates; (2) good blast fragmentation; and (3) secure pulling-horizons. A full-scale rock mechanics study was carried out involving: numerical modelling studies; pulling ellipse analyses; blast design, monitoring and analyses; laser profiling; and time domain rej7ectometry (TDR) instrumentation. The final recovery scheme, employing a controlled failure, involves recommendations on: (1) blasting techniques; (2) support systems; (3) mining sequences and scenarios; and (4) monitoring systems."

Jan 1, 1994

By Robb. V. M., F. Walraven, L. J. Robb

"Abstract -The old Albert Silver Mine is a polymetallic deposit comprising concentrations of Cu­ Pb-Zn-Ag-U-F within a set of sub-parallel quartz-hematite veins which occur within the fine-grained apical phase of the 2050 Ma old A-type Bushveld granites. Mineralization occurs as an early pyrite­ chalcopyrite-arsenopyrite-galena-sphalerite-(argentiferous) tetrahedrite paragenesis followed by a later, more oxidized assemblage comprising chlorite-hematite-fluorite-pitchblende. Accumulation of metals appears to have taken place at the interface between a coarse-grained porphyritic granite and an overlying fine-grained phase: veins occur in the latter and represent leakage of magmatic fluids from the differentiated, water-saturated, subjacent granite.Mineralization processes in the Bushveld granites are believed to be related to long-lived circulation of dominantly magmatic fluids stimulated by the high heat productive capacity of the host rocks. Endo- and exogranitic tin-tungsten and base metal mineralization formed during an evolving hydrothermal system that lasted for several hundred million years, forming innumerable small- to medium­ scale polymetallic deposits. At the Albert Silver Mine, unroofing of the cover sequences at circa 1600 Mato 1700 Ma resulted in the incursion of lower-temperature, high-f02 meteoric fluids which remobilized the earlier sulfides and introduced the paragenetically late U-F mineralization ."

Jan 1, 1994

By Tai Sik Lee

Why ISRU into Space Exploration are important NASA and International Mission statements calls for the sustainable human exploration of the Moon, Near-Earth asteroids, and Mars Common Exploration Goals and Objectives are Strongly influenced by ISRU Extend Human Presence: Continually increase the duration and level of self sufficiency at all destinations Develop Exploration Technologies and Capabilities: Develop and validate tools, technologies, and systems that extract, process, and utilize resource to enable exploration missions Perform Science to Support Human Exploration: Characterize available resources at destinations Stimulate Economic Expansion: Encourage commercial services and create new markets, including markets for discovered resources Enhance Earth Safety: Test techniques to mitigate the risk of asteroid collisions with Earth

May 1, 2013

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 J. Dupre, A. Gontcharov, H. Pepin

Produced by the conventional TIG welding CMSX-4 welds had been studied. It was demostrated that microstructure of welds depended on filler materials, welding parameters and joint design. Epitaxial solidification of CMSX-4 clad deposits produced a directionally solidified structure while welding with the similar filler material. Defects free clad welds were obtained by TIG welding without preheating using similar and dissimilar filler materials.

Jan 1, 2006

Gold recovery from refractory ores can be very difficult and complicated depending on the causes of the refractoriness. Typically, a fine wind and/or the oxidation of the gold-bearing sulfide minerals are required to liberate gold from the host rock matrix. Mineral separation techniques, particularly surface¬wettability based separation (i.e., flotation) and magnetic separation, can be used to pre-concentrate the gold and sulfide minerals, or to remove mineral species that are harmful either to the oxidation of the gold-bearing sulfides or to the cyanidation following the oxidation. In this paper, several processes are described, including oil-agglomeration flotation recovery of fine-grained gold and sulfide, reverse flotation of carbonate minerals prior to pressure or bio oxidation, reverse flotation of elemental sulfur after pressure or bio oxidation but prior to cyanide leaching, and magnetic concentration of gold-bearing iron oxides. The integration of these techniques with gold hydrometallurgical processes may make the economic recovery of gold from an otherwise uneconomic refractory ore possible.

Jan 1, 2011

By Michael G. Rulff, Tracy M. Holmes

"Vast amounts of time and money are spent fighting flow problems in plants that involve the handling or processing of industrial minerals. Because these types of projects tend to be capitalintensive, the right decisions, made at the design stage, can have a substantial positive effect on the economics of the project.Some of the problems related to solids flow in mineral processing plants include:•,Flow stoppages•,Uncontrolled flow•,Segregation of blended materials•,Build-up and dead material resulting in loss of live capacityUnfortunately few Universities in North America provide courses in the design or selection of bulk solids handling equipment, let alone the theory of bulk solids flow, with the result that engineers do not fully appreciate the effects of bulk solids handling on their process. The usual method of selecting “standard” equipment, all too often, leaves plant operators hammering on hoppers to promote flow, a technique that is not only usually ineffective but also unsafe and often causes damage to equipment. In short, too little consideration is given, at the design stage of projects, to the particular material and operating environment involved and how these will affect handling between process steps.This paper seeks to give a general understanding of bulk solids flow theory including flow patterns and flow property tests, and presents functional design guidelines to ensure reliable flow. As well, a case history will be presented. Our message is clear: To ensure uniform, reliable flow, a plant design must take into account the specific flow characteristics of the bulk solid to be handled or processed."

Jan 1, 2008

By Y. M. Zhao, C. L. Duan, Z. F. Luo, X. L. Yang

"Fine coal beneficiation in a dry way is considerably imperative for the efficient utilization and conservation of coal resource in drought regions, especially for China. In this study, a continuous vibrated gas-fluidized bed separator was established and developed based on the results of laboratory batch separation results. The fluidization behavior and the effects of several main parameters including superficial air velocity, vibrational parameters, bed height and separating time were systematically investigated. The results showed that the bed expansion increased linearly with the superficial air velocity and theoretically, higher bed expansion benefited the hindered settling process of fine coal particles. However, larger superficial air velocity would induce intense fluctuation in bed surface and a poor performance of density segregation. The conveying velocity of particles was mainly determined by the vibration angle and a predicted model was established by the nonlinear regression analysis. A theoretical model of bed height distribution was established and this model fitted the measured value well. The beneficiation performance of this separator was evaluated by separating -3+1 mm Wuhai fine coal. The results showed that the probable error, E, is 0.225, indicating a continuous vibrated gas-fluidized bed separator could achieve a satisfactory performance.INTRODUCTIONFine coal beneficiation in a dry way is considerably imperative for the efficient utilization and conservation of coal resource in drought regions, especially for China. Meanwhile, it is also conducive to environment protect and low-carbon, green development of coal sector. In recent years, the increasing academic interest in the field of fine coal dry beneficiation has been aroused in most of big coal countries. In summary, recent processes of fine coal dry beneficiation are, according to their processing principles, mainly classified into two categories: dense medium beneficiation (Dong et al., 2015; Fan, Chen, Zhao, & Luo, 2001; Luo et al., 2008; Macpherson, Iveson, & Galvin, 2011) and improved pneumatic beneficiation (Patil & Parekh, 2011; Yang, Zhao, Luo, Song, & Chen, 2013; Yang, Zhao, Luo, Song, Duan, et al., 2013; Zhao, Zhao, Chen, & Luo, 2015). The former deploys artificial dense medium, such as magnetite powder and fine sand, to form a stable gas-solid suspension with certain density under the function of the upward fluidizing air flow and in some case, the external force field like vibration and magnetic field. Generally, it is believed that the process of air dense medium fluidized bed (ADMFB) is suitable for separation of coarse coal (-50+6 mm) and can't obtain a satisfactory result for fine coal separation (Luo, Chen, & Zhao, 2002; Luo et al., 2008). However, some recent laboratory efforts (Patil & Parekh, 2011; Zhang et al., 2014) attempt to find an improved performance for fine coal beneficiation in ADMFB with some modifications. The point of these works is to use a comparatively shallow bed and finer magnetite powder with appropriate size distribution. It is known that fluidization of finer magnetite powder is prone to arouse adverse fluidization properties such as channeling and slugging. Thus, the external force is introduced to an ADMFB in order to improve the fluidization quality of a magnetite powder bed. Some recent literature on air dense medium magnetically stabilized fluidized beds (Fan et al., 2001; Luo, Zhao, Chen, Fan, & Tao, 2002; Song, Zhao, Luo, & Tang, 2012), air dense medium vibrated fluidized beds (Luo et al., 2008) and Reflux Classifier (Macpherson, Iveson, & Galvin, 2010) reports that the separation efficiency, namely the probably error E value, of dense medium separation of fine coal ranges from 0.066 to 0.07, indicating a good separation performance. But, the main unresolved problems of dense medium beneficiation are located in the processes of product purification and medium recovery and are urgent to be solved befor"

Jan 1, 2016

By W. A. Dixon Edwards

Gravel deposi ts in the Edmonton region are unique in their diversity in origin and age. The deposits were described first around the turn of the century (Dawson and McConnell 1896) . Among the many more recent in vestigations are works by Rutherford (1936), Shelley and Associates Limited ( 1977) and the City of Edmonton (1978) .

Jan 1, 1984

By Rob Morrison, Peter Cameron

"Many products and technologies have been developed from outcomes of research projects carried out by the Julius Kruttschnitt Mineral Research Centre (JKMRC). When these products and technologies are applied to the design and optimisation of blasting, comminution and separation, improvements in profitability can be realised.In 1970 Alban Lynch promoted two practical ideas to improve plant operations:• Ore and equipment properties can be separated allowing experience with one type of ore or equipment to be transferred to other types of ore and equipment. If this experience was encapsulated in a mathematical model, then these properties could be combined and used to simulate (ie. to design and to optimise) complete mineral processing circuits.• Many problems associated with scale-up from laboratory to industrial equipment could be eliminated by experimental work on full-scale equipment in the plant.Many JKMRC research projects have focussed on the development of models of unit operations in mineral processing and their application to process simulation.Models of comminution and classification developed at the JKMRC have been used since the early 1980's. Ore characterisation techniques developed to support these models are licensed world wide through JKTech. The application of comminution modelling techniques to blasting, which optimises the process feed size distribution is used in Mine-to-Mill® projects. The advances in the understanding and modelling of froth flotation over recent years have provided the opportunity for integrated ore characterisation and process optimisation from resource to product.JKMRC project outcomes often provide proven opportunities for the mineral industry to improve performance and productivity. JKTech was established in 1986 to commercialise and market the most promising outcomes and thus ensure their continuing availability to the mineral industry.They include:• Commercial software (JKSimMet, JKSimBlast and JKMetAccount).• Monographs (Comminution and Blasting).• Technologies (Mine-to-Mill® and flotation optimisation).• Hardware products (JKFrothCam, JKJetLift® and the Mineral Liberation Analyser).This paper summarises these technologies and their benefits."

Jan 1, 2003

By R. H. Duval

"In May 1936, Pamour started producing gold by cyanidation of flotation concentrates, and in 1939 was milling about 1, 600 tons per day.Refining records dating from 1939 show two oil-fired furnaces in use, (Rockwell type 46 11 x 29 11 inside oval shell).Refining time averaged 7. 83 hours during the year 1939, indicating a complete refining shift of about 9. 33 hours. That year appears to be characteristic of the period with regard to time required and results obtained.For that year total fineness (gold + silver) of the bars averaged 940 (approx.), but it frequently dropped below this figure, sometimes far below.Furnace lining life varied widely from three to seven or more months. Sillimanite was the standard lining but Mullfrax 41 was frequently used.For many years refining practice remained practically unchanged, and in 1960 procedure still consisted essentially of mixing a flux(% Composition Borax 41, Silica 11, Soda-Ash 11, Nitre 15, Mn02 22) with cyanidation precipitate in the ratio of l. 2 to l and heating to a medium heat (yellowishred, 2000° F) with a low flame for a long time. Time required was about 10. 5 hours per refining. Results were still much as detailed above.At this time it was decided to revise refining procedure, in an effort to shorten refining time and obtain consistently good bullion fineness."

Jan 1, 1965

By L. I. Kiss, A. Larouche, V. Dassylva-Raymond

Control of the quenching capacity of the cooling water is of primary importance for maintaining the quality and recovery rate of ingots produced by direct chill casting. Industrially, this can be done using a cylindrical metallic probe undergoing rapid quenching by direct immersion in a reservoir filled with casting water. Such a test rig originally developed at Alcan Arvida Research and development Centre was modified and used to assess the role of key parameters affecting the boiling heat transfer. During the tests, the probe of the instrument undergoes the effects of different heat transfer mechanisms. An experimental study was performed in order to clarify the details of the probe-water heat transfer during rapid quenching. The heat flux along the surface was determined by mathematical modeling using the measured temperature signals, while the corresponding heat transfer regimes like stable and unstable film boiling, nucleate boiling and natural convection were identified by the analysis of high-speed video recordings. Aluminium

Jan 1, 2006

By B. R. Rakishev

When transferring from the railway transport to the combined automobile-conveyor transport by stripping works at coal mines, it was proposed to form at the working zone a concentration horizon for reloading part of the stripping volumes at the railway transport. The procedure is adduced for substantiating parameters of bloc-panels, depending on the step of transferring of reloading points in interrelation with the intensity of the working zone?s development with observing the balanced movement of parts of the stripping zone relative to the temporary concentration level.

Aug 1, 2013

By A. M. Abdel-Rehim

The present work reports a study of production of thorium concentrate from Egyptian monazite by decomposition of ammonium carbonate solutions containing ammonium thorium and uranyl carbonate complexes. These solutions were obtained from the processing of monazite by alkaline leaching in ball-mill autoclaves, followed by selective separation of thorium and uranium from lanthanides by autoclave leaching of the hydroxide cake obtained with ammonium carbonate - bicarbonate solutions. The separation of thorium and uranium in the form of thorium concentrate from their carbonate complexes was achieved by different methods, including neutralization of solutions at pH = 6.7 by acid, addition of alkali at pH = 11.5, heating of solution at 100°C and processing of carbonate solution with steam under pressure in steel autoclaves. Processing of solutions of thorium and uranyl carbonate complexes in an autoclave with steam causes their decomposition. Complete recovery of thorium 99.8% and 98.4% uranium recovery in thorium concentrate was attained at 120°C and steam pressure 2 atm, within 10 min. Meanwhile, the recovery of lanthanides was low and did not exceed 1.1%. The thorium concentrate produced contains 67.82% Th, 4.6% U and 3.14% REE. All methods achieve complete separation of thorium and uranium from their carbonate solutions, but the first two methods are unfavourable for the industry due to the high cost of reagents and their inability to regenerate the ammonium carbonate. The decomposition of ammonium thorium and uranyl carbonate complexes with steam under pressure is recommended for industrial application for its simplicity and the ability to regenerate the ammonium carbonate.

Jan 1, 2004

By G. G. Bowser

THE time has come when, as your President, 1 turn the helm over to my worthy successor. When 1 was reminded by our Secretary that 1 had to prepare an address for this meeting, 1 was at a loss for a subject. In the hope of inspiration 1 perused the records of our Society for some years past. 1 found in these records that many problems in need of solution relative to industry in Nova Scotia were discursively dealt with and that sound thought was given to the solution of these problems, with a natural leaning, of course, to problems pertaining to the mining industry. 1 found also that some of the reasoning was remarkably prophetie. Some of these subjects and problems were: The use of pulverized coal to generate power instead of hydro-electric power; rural electrification; the importance of youth training for an efficient place in industry; the proper marketing of coal; the fuels competing with coal; the need for better in-dustrial relations between employer and employee; better education for success in the social field as applied to industry; and Canadian unity. The issue of some of these copies has been forced upon us by war. For instance, there appears to be no marketing problem for coal, nor does there ? seem to be a marketing problem for anything just at present. The problem of the coal producer just now is supply and transportation. Also, at present, coal fe.ars no competitors, such as oil-and not even hardwood. Many large companies now have an industrial Relations or Personnel Manager and department. Furthermore, we have been compelled of necessity to train our young men, and women also, for both industry and war. However, war does not solve these problems and, with the return to normal times, we may be faced with the same troubles in even greater measure. My reason for mentioning these copies is to point out that, as mining men, we are aU desirous of progress in every industry, not only the mining industry; and that mining men are able to see clearly ahead. In normal times, especially in matters not directly affecting the mining industry, we are inclined to let matters take their own good rime, or let the government do it. We do not seem to realize that these necessary and desirable changes can be made in times of peace-instead of being forced upon us by war or other social upheavals-by the method of sound thought and action to the desired end.

Jan 1, 1943

By N. J. Shackleton, N. A. Chapman, V. Malysiak, C. T. O’Connor

In this study, the effect of using conventional crushing and high-pressure grinding rolls (HPGR) in combination with dry or wet milling was investigated using a base-metal sulphide (BMS) sphalerite and a platinum group mineral (PGM) ore to determine how these processes affect the flotation performance. In sphalerite, irrespective of the crushing procedure (HPGR or conventional), dry milling resulted in the highest grades and recoveries of zinc, whereas in PGMs, similar treatment produced the poorest results. The results were investigated further by the effect of factors such as percentage liberation and particle size on the flotation results.

Jan 1, 2012

By W. P. Campbell

THE investigation herein described had its beginning in the chemical laboratory of the Department of the Interior, Calgary. After the transfer of the natural resources to the Province of Alberta in 1930, the laboratory was closed and the investigation discontinued, but in 1933, with the permission of the Director of the Mines Branch, the work was again taken up and brought to completion. OBJECT OF THE INVESTIGATION The object of the investigation as originally planned may be stated as follows : (1) To determine the chemical composition of the limestone formation underlying Turner Valley gas field. (2) To identify 'beds' in the limestone, if such existed, with definitecharacteristics which would mark them from immediately overlying and underlying measures. (3) To relate information acquired on the composition of the limestone to the occurrence of oil and gas in the particular section examined. Definite information was lacking as to the exact chemical composition of the limestone and of its variations in composition at various depths. The formation was generally referred to in the field as the 'dolomitic' limestone, but the depth to which the dolomitized zone extended and the degree to which the limestone generally had become dolomitized were not known. Jn the drilling and logging of wells, the recognition of suitable 'markers' in the various formations is a matter of some importance. Markers are generally relatively small but widespread members of a formation, which have some characteristic property, of colour, composition, or form, by which they may be identified, and with them, consequently, the formation of which they form a part. In the formations above the limestone in Turner Valley, a number of well defined and easily recognized markers are known to geologists, drillers, and others interested in the field. Many of these markers Hand out in sharp contrast to adjoining measures and are therefore easily recognized; in others, the contrast is less sharp, with consequent difficulty in identification.

Jan 1, 1937

By N. Staroselsky

"Significant energy savings are often possible for centrifugal compressors operating in parallel by improved control strategy and improved instrumentation. Blow-off can usually be reduced by improved surge control combined with a better control strategy for loading and unloading the group of machines. More precise and stable pressure control then becomes possible. This improved control strategy will also decrease the frequency of operation near the dangerous limits of surge or overload or overspeed. A sample station of mixed centrifugal and reciprocating compressors is examined and a substantial energy saving with the recommended control strategy is projected from operating data. Present Operating Conditions of the Compressed Air StationThe Compressor StationThe compressor station described here has three centrifugal compressors and three reciprocating. It supplies a mine in New Brunswick.Compressed Air and Power ConsumptionFigure I and Figure 2 provide graphs of air consumption and pressure changes based on the owner's data.During the typical two-shift operating day (Fig . I) in the non-productive shift (midnight to 8:00 a.m.), the consumption stays at a level of 9,000 SCFM. This corresponds to a pressure of 110 PSIG. Then, after 8:00 a.m ., the air consumption starts to increase and th e pressure decreases. Around 10:00 a.m., the consumption reaches its maximum level at 97 PSIG. Around II :30 a.m., the air consumption starts to decrease because of the production drop during the lunch break of the first shift. Pressure increases again up to 109 PSIG. After the break, consumption rises to its maximum level over 16,000 SCFM andpressure drops to 97 PSIG.Around 2:30 p.m., the air consumption drops sharply to 9,000 SCFM because of the production decrease to zero level. This drop results from changing of shifts. The pressure at this time increases again up to 110 PSIG. The second shift (2:30 to II :30 p.m.) is an alogous to the first.During the three-shift operating day, the break around 4:00 . a.m . and the shift change around 6:30 a.m. cause sharp drops in air consumption. The pressure for almost the entire night shift stays near 110 PSIG because the station is working with blowing-off even under the maximum consumption. The analysis of Figures I and 2 shows that the pressure varies with the air consumption changes. During non -productive time (non-production shifts , shift changes and breaks) or during the night shift, the total station capacity is proportional to the discharge pressure. By decreasing the level of this pressure up to 97 PSIG, the flow of the station may be decreased during the non-production time as follow s:"

Jan 1, 1980

By F. Weinberg

"The recent development of the continuous casting process for steel has required basic understanding in a number of areas in the metallurgcal sciences. In some areas, information is still lacking. The success of the application of basic knowledge and research to the process is evidenced by the fact that a large percentage of the steel now produced in the world is produced by continuous casting.A number of areas in which metallurgical science has contributed and is currently contributing to better design and control of the continuous casting process and leading to a better quality product will be considered. These include:(a) heat transfer studies of the entire casting process;(b) fluid flow in the tundish, strand and liquid metal stream;(c) solidification structure and segregation;(d) strength and ductility of steel at high temperatures related to bulging and cracking; and(e) problems related to horizontal casting developments.IntroductionThe continuous casting of steel is a relatively new technology in steelmaking. It is now used extensively throughout the industry. In Japan, for example, continuous casting accounts for approximately 40010 of steel production, and this value is expected to increase to over 50% in the near future . New steel plants are now designed to use continuous casting exclusively. This means the process must work well and be completely reliable, because all the steel produced must go through the caster.The development of the continuous casting process in a short period of time has required concerted research and development in many areas . I shall cite a number of examples of these developments and refer to work done in Canada when applicable. No attempt will be made to review all of the research in continuous casting, nor refer to all of the workers in the field.The developments in continuous casting are based in many cases on metallurgical science, as described below. The use of metallurgical science in these developments is qualitative, in that concepts and idea s are used, as opposed to quantitative values calculated from fundamental equations. In general, most metallurgical problems are too complicated to enable fundamental equations to be used without the introduction of uncertain approximations and boundary conditions in the calculations.Starting at the beginning of the steelmaking process, very extensive research and development has been carried out to produce liquid steel of the required composition and temperature. The replacement of open hearth furnaces with BOF furnaces reduced refining time from many hours to roughly 30 minutes for 250 tons of steel. Two BOF furnaces effectively enable a continuous flow of steel to be available in a plant, essential for the introduction of the continuous casting process. This area of research will not be considered here."

Jan 1, 1981

By R. L. Eadie, J. L. Luo

The effect of plastic deformation on near-neutral pH stress corrosion cracking (SCC) also known as environmentally assisted cracking was studied by cracking rate measurements. All the tests were conducted in a synthetic near-neutral pH solution. The traditional potential drop tests using compact toughness (C-T) specimens with 2-3 mm long pre-cracks showed varying plastic deformation by rolling would increase the material's susceptibility to SCC. This was confirmed by cyclic loading tests using double notched flat tensile specimens with 200-300 µm long pre-cracks which gave the same results that the specimen with large scale plastic deformation by tensile loading had a relatively faster crack growth rate than that with only small scale plastic deformation.

Jan 1, 2005