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By J. P. Landriault, F. W. Harrison

"Zinc-iron alloy coatings can be produced by either thermally alloying hot-dipped galvanized steel or by electro deposition. Stelco Inc. produces a thermally alloyed Zn-Fe alloy-coated steel, which is mechanically wiped to remove free zinc.A more extensive use of Zn-Fe alloy-coated steel has been predicted for unexposed autobody and structural part applications, since this material is characterized by good spot weldability and formability, and provides superior corrosion resistance under automotive primers.This investigation has examined the coating composition, corrosion resistance, spot weldability and formability of Stelco's Zn-Fe alloy-coated steel and found its properties to be similar to those of Zn-Fe alloy-coated steel produced by post coating annealing.IntroductionRecently, there has been increased automotive interest in galvanneal, which is characterized by good spot weldability, good paintabilityt and good corrosion resistance when primed. Stelco produces a thermally alloyed zinc-iron coated sheet product similar to galvanneal. However, this product is produced by mechanically wiping the free zinc from the surface of hotdip galvanize to expose the underlying zinc-iron alloy.The surface of Stelco zinc-iron alloy-coated sheet is matte gray and has longitudinal streaks which result from contact with Kevlar wipers during production (Fig. I). This paper describes the coating composition, corrosion resistance, weldability, formability and surface appearance of Stelco zinc iron alloy coatings and, wherever possible, compares these properties to those of galvanneal."

Jan 1, 1987

By J. Goyman, K. R. Rawling

"1.1 Location and Transportation ServicesNanisivik Mines Ltd. is located at latitude 73°, 3,200 km north of Montreal and 700 km north of the Arctic circle, on the south side of Strathcona Sound, which is an arm of Admiralty Inlet, in Northern Baffin Island. The orebody and mill site are 4 km distant from Strathcona Sound which provides deep water anchorage for ocean transportation of concentrate to Europe during the short northern shipping season from mid-July to mid-October.The operations and the resident community have direct jet aircraft service from Montreal two days per week, and local nights connect with other Arctic communities in the northern Baffin region. Bulk supplies and general cargo are delivered in the summer shipping season.1.2 HistoryThe Texas Gulf Sulphur Company, now Kidd Creek Mines Limited, staked claims in the Nanisivik area in 1957 and carried out exploration through to 1968. After the Kidd Creek orebody was found, Texas Gulf optioned the property in 1972 to Mineral Resources International Inc. (MRI), which undertook further exploration and completed a feasibility study.Nanisivik Mines Ltd. was formed in 1975, with MRI as the majority shareholder and minority shareholdings held by Metallgesellschaft, Billiton and Texas Gulf. Strathcona Mineral Services Limited was retained to manage the project during both the construction and operational phases."

Jan 1, 1984

By Steve Wilkinson

"""Techniques for coarse-particle beneficiation of some gold ores and methods for determining potential for sorting any gold ore deposit.""With the advent of high speed computers, laser technology end different types of electronic sensing devices, ore sorting machinery has been developed, capable of handling significant tonnage rates while maintaining high level efficiency. Gold ores may be amenable to coarse-particle beneficiation where there exist measurable criteria upon which there can be recognition of auriferous versus barren lumps in the run of mine. Three types of criteria are suitable for sorting and are:i) Photometric - optical variance between ore and waste such as vein ores hosted by barren country rock;ii) Conductivity/Magnetic - based upon the metallic mineral content of ore end waste, and its association with Au, such as found in sulphide/arsenide Au ores,iii) Radtometric - detection of natural gamma activity occurring with uranium-bearirig gold ores.The method for determining the sortability of an ore depositconsists of, at least, three stages:i) Initial stage identification of ore and waste types,mineralogical/petrographical associations,amount of dilution in P.O.M.establishment of any sorting criteria]"

Jan 1, 1985

By Lee Nichols

Convergent Bitumen Recovery Context of discussion It should be noted that the CBR process is a conceptual bitumen recovery feed methodology, designed to provide supplemental bitumen to the oil sand operations of Northern Alberta. To date the following have beencompleted. ?Bench Scale testing. ?Peer group brainstorming. ?Energy Balance ?Confidentiality agreements have been signed with several companies Discussions are ongoing with industry and although conceptual atthis stage the process holds significant promise.

May 1, 2007

By Jamie King

This paper describes the use of dynamic scheduling and discrete event control to provide coordinated control of multiple automated vehicles. In the past decade there have been significant advances in the field of robotics for underground mining. As this trend progresses toward a realization of a completely automated underground mine the need for a central control system, capable of providing coordination for multiple vehicles in a semistructured environment, becomes more evident. In the past year general research into multi-robot coordination has been applied to the underground mining scenario and demonstrated in a scaled model underground mine in a laboratory setting. This system shows significant potential to be adopted into a full-scale implementation for mine wide automation.

May 1, 2001

By E. Gallestey, D. Groenveld, F. Kolb, M. Rozou

"Recent copper price evolution pushes modern mining industry even harder to achieve highest production with maximum efficiency. Operations are bound by numerous contractual and environmental conditions that bring a high degree of complexity to both the operators controlling the process and the plant managers assessing the circuit’s potential and setting the production goals.Advanced process control (APC) for grinding is one important tool to operate this most energy intense area in an optimal way, finding the optimal trade-offs between highest throughput, energy efficiency and product quality based on variable ore properties, production targets and management priorities.ABB’s state of the art control and optimization software platform enables user to design a controller based on model predictive control (MPC). The paper and the presentation show the technology used and the results achieved through an APC controller installed in a pilot project in Aitik (Boliden SA), Sweden. Furthermore, possibilities to interconnect grinding with other areas as stockpile management and flotation with various interconnected APC controllers will be shown. Finally, an example of the return on investment and the payback times based on the increased throughput and better product quality will be presented.INTRODUCTIONDepending on the ore characteristics and the targeted plant capacity, the design of the grinding circuit may vary significantly. Typically, the circuit consists of several mills (rod, ball, SAG, AG) in series and/or parallel with a number of classifiers and sumps at appropriate locations (see Figure 1).The main goal of the grinding section is to reduce the ore particle size to a level that enables efficient separation between gangue and precious metals in the subsiding processing step. The trade-off between quality and quantity has to be made. At the same time, it is also crucial to execute this process at the lowest possible energy and grinding media consumption."

Jan 1, 2015

By E. C. Morton

The Western Australian School of Mines (WASM) has developed a facility for the static testing of large scale ground support elements. The samples are loaded using a mechanical screw feed jack. Instruments measure the displacement and the load being applied. Methods have been developed for testing of mesh, shotcrete and membranes. Mesh samples are restrained on all sides and loaded centrally. A new large scale punch test method has been developed to evaluate shotcrete and membranes. These products are sprayed on to a sandstone substrate containing a centrally located isolated disc. The sprayed product is loaded by displacing the disk. The different test methods are described in detail. The test program involved two types of mesh, several shotcrete mix designs with different curing times and one membrane product. The force-displacement responses are used to directly compare the products. The implications for implementation of the different ground support products are discussed.

May 1, 2009

By M. Mirnezami, D. Lascelles, J. A. Finch, E. El-Ammouri

"In a previous publication, the depressant action of Mg above pH 10 on Cu-activated sphalerite was described (Lascelles et al., 2001). In the present communication, a second role, aggregation is introduced.Aggregation (i.e., the tendency of particles to cluster) is measured using settling rate and turbidity converted to an aggregation index (AI) where 0 corresponds to dispersed and 1 to aggregated. Surveys of Cu and Zn flotation stages at four concentrators showed the A1 increased significantly above pH 9. The metal ions identified in the process waters, principally Ca and Mg, were tested to determine which might be responsible. The presence of Mg was found to be the most important, 50 ppm Mg having a greater impact than 500 ppm Ca fkom pH 9 to 1 1. In one plant, poor repeatability in A1 was suspected to be related to varying Mg levels; doping with Mg significantly increased AI.In both aggregation and depression, therefore, the common feature is the impact of Mg at pH > 9. Over this pH range Mg forms a range of hydroxy species, including Mg(OH)2 precipitates. Suggested aggregation and depression mechanisms associated with these precipitates are introduced. Possible problems and opportunities arising from the findings are discussed.INTRODUCTIONProcess waters in flotation circuits contain a variety of metal ions that may introduce unwanted activation or depression. Two common metal ions are calcium and magnesium. Typical concentrations are in the range 50 ppm Mg and 500 ppm Ca (Marticorena et al., 1994, Basilio et al., 1996, Negeri et al., 1997, Nesset et al., 1998)."

Jan 1, 2002

By Jean-Jacques Bouillon, Michel Jébrak, Stephane Faure

"Le gisement polymétallique (Cu-Zn-Au-Ag) des Mines Selbaie est forme par un réseau de filons encaisses dans une séquence de pyroclastites felsiques du sill on Harricana-Turgeon. Les minéralisations sont encaissées dans le tuf de Selbaie, situe sous une épaisse séquence d'ignimbrites Iitées. Ce gisement se distingue des autres gites archéens par une chronologie atypique des minéralisations: les veines de chalcopyrite, de sphalérite et de galène recoupent un amas exhalatifpyriteux stérile. Un vaste halo d'altération hydrothermale a chlorite et mica blanc est associe à cette minéralisation.La mise en place des veines minéralisées est associée à une phase d'extension NNW-SSE. Le complexe volcanique subit, par la suite, trois phases de déformation. Une compression, orienté N-S, développe une schistosité à peine pénétrative et un réseau de fentes de tension. Une réorientation des contraintes locales selon une direction WNW-ESE conduit au chevauchement de I' écaille d'andésite et de tonalite de Brouillan. Un réseau conjugue de failles normales cassantes est associe au relâchement des contraintes."

Jan 1, 1990

By Christian Bourcier

La méthode d?exploitation traditionnelle de la mine est le chantier chambre-magasin. Cependant, lors de l?exploitation d?un chantier, nous avons été confrontés à un problème de soutirage. Le minerai abattu est resté accroché à l?intérieur du chantier ce qui nous obligea à soutirer environ 200 wagons, représentant 700 tonnes. Suite à l?ampleur de la situation, nous avons décidé de finir l?exploitation du chantier par la méthode sous-niveau long trou retraité. Cette première expérience de récupération de piliers ayant été réalisée avec succès, nous avons décidé de continuer avec deux autres récupérations de piliers afin de pouvoir augmenter notre expertise autant au niveau technique qu?au niveau économique.

Oct 1, 2001

By C. J. Brown

Since its commercialization thirty years ago, the Recoflo® short bed ion exchange process has been extensively utilized for the recovery of a wide variety of acids and metal salts. In addition to a reduction in resin bed height from 200 cm to 300 cm to 15 cm to 60 cm, the process has a number of features such as utilization of fine mesh resins in a compressed bed which together make it ideal for a number of applications. The process has been extensively exploited, for example, in the metal finishing industry for recovery of valuable chemicals from electroplating, anodizing, etching and pickling wastes. More recently, it has also been applied in the primary metals industry for purification of copper electrolytes and metals recovery from leachates. The paper discusses several of these applications and some of the issues that were found to be key to their success.

Jan 1, 2004

By Lyne Côté, Jose Adante

"The Caribou underground mine, 50 km west of Bathurst, the Restigouche open-pit mine, another 30 km west and the concentrator located at the Caribou mine site resumed operations in July 2007 after a nine year shutdown. The Caribou operations achieved commercial production on Jan 1. By June, 2008, all metallurgical targets had been achieved or surpassed with the production of lead and zinc concentrates assaying approximately 50% Zn and 45% Pb respectively with recoveries exceeding 80% for Zn and 70% for Pb.The deposit features very fine-grained massive sulphide mineralization, which in the past has proven difficult to process. ISA Mill Ultra Fine Grinding Technology in combination with conventional flotation technology is used to process these complex oresSeveral modifications arising from experience gained from past operations, an extensive research project at Lakefield Research and post startup flow sheet and reagent alterations have been employed to achieve this break through performanceThis paper describes the design, start up and optimization of the Caribou operations including the many challenges faced including the flotation of mineral particles with K80s ranging from 35µm to 8µm.HISTORICAL BACKGROUNDThe Caribou massive sulphide deposit was discovered by Anaconda geologist Cam Cheriton in 1959. Anaconda initiated an extensive underground exploration and discovered a super gene copper blanket which was developed into a small open-pit mine-mill operation that ran from 1970 until the depletion of the copper ore in 1974. East West Minerals, an Australian public company, purchased the mine in 1986 and operated for only seven months producing a single bulk lead-zinc concentrate. In 1995, Breakwater acquired the Restigouche Open pit and Caribou underground deposits. Breakwater began milling operations in July 1997 but Caribou Mine failed to commercialize production, and the company decided to shut it down in August 1998, because of declining metal prices. The mill was plagued by mechanical and design problems, but deficiencies in metal recoveries prevented the operation from reaching desired levels."

Jan 1, 2009

By M. L. Goble

"Inco Metals Ltd. (Manitoba Division) operates a mining, milling, smelting and refining complex, 500 miles north of Winnipeg in central Manitoba. The Thompson Mill is presently operating at 12,000 S.T.P.D. on ore from both underground and open pit mines. The ore is treated in two separate milling and flotation circuits utilizing a common crushing system which is located inside the main mill building. The milling facility employs approximately 43 operating employees, 30 maintenance employees and 20 staff in supervisory or process development roles.In recent years an increasing awareness of the potential hazards of contaminants in the work place has made it mandatory that all employers maintain careful and accurate records of the work environment to which each employee has been exposed during his working career.The importance of this record keeping and general observation of the work place cannot be over emphasized. Proper monitoring of the work place provides an accurate and complete record of the contaminants and physical agents to which an employee is exposed during his work career. This can aid in studies which might be conducted in the future and can also be used as a basis for instituting improvements to the workplace."

Jan 1, 1980

By J. E. Udd, L. P. Geldart, B. B. Dhar

"Solutions for the stress distributions around simulated underground openings have been limited to calculations of boundary stresses for simple openings in which the boundaries may be expressed in mathematical terms. Studies involving circles, ellipses and ovaloids are re-ported in the literature.The stresses on the boundary of an opening and those at a distance from it in the medium are of concern to the engineer. The former may be related to the greatest concentrations of stresses encountered; the latter have a bearing on the identification of the ""zone of influence"" of the opening.Recent advances, in the form of a derivation for the stresses at a distance from an opening of elliptical shape, together with a solution derived previously for stresses in depth around ovaloidal openings, have been combined with computer programming techniques to provide complete solutions for a wide range of cases and variables. Some typical results which, it is hoped, may have some application to the design of underground openings are given herein."

Jan 1, 1970

By Jie Zhou

Mining mobile equipment is becoming larger in order to lower operation cost and increase productivity; however, their performance characteristics are often limited by the tire capabilities. Although considerable progress has been made in the field of tire research, the lack of comprehensive knowledge on tire performance characteristics impedes the advancement of off-the-road tires. Longer haul roads, and a severe operating environment make tires more vulnerable than other components of a vehicle. Furthermore, due to a limited availability of large tires, mines are facing shortages. Thus mines and tire service companies are keen to improve tire performance, extend tire life and hence lower operating costs. This paper reviews the relevant tire performance research, analyzes tire interactions with the surrounding environment, tire maintenance practices and operational issues using a case study based on data collected during an ongoing project with Fountain Tire.

May 1, 2006

By Mike Ounpuu

"Locked cycle testing has become more common practice in the last 10 years. Reasons vary from a desire to avoid pilot plant testing, demand for more variability testing within deposits, and perhaps most importantly, a request from the financial institutions who invariably finance many of the projects. Surprisingly, many people don’t understand locked cycle testing, analysis and balancing. This paper provides a brief overview of locked cycle testing, and then progresses into a more detailed discussion on the analysis and balancing of locked cycle test data. The paper endeavors to educate CMP personnel on how to determine if the test was good and if a reasonable metallurgical projection was made. The paper uses case studies to illustrate the key points.INTRODUCTIONA locked cycle test is a repetitive batch used to simulate a continuous circuit. The basic procedure has a complete batch test performed in the first cycle which is then followed by similar batch tests which have “intermediate” material from the previous cycle added to the appropriate location in the current cycle. These batch tests, or cycles, are continued in this iterative manner for an arbitrary number of cycles. The final products from each cycle, i.e. final concentrate and final tailings, are filtered and thus removed from further processing. At the end of the test, all the products, final and intermediate, are dried, weighed and subjected to chemical analysis. The test is balanced and a metallurgical projection is made.This description can be found in many of our classical textbooks for the mineral engineer 1, 2, 3,4. Unfortunately, none of these textbooks provide any discussion beyond the basic procedure. Often, they provide comments such as in Taggart’ where he states; “It is questionable whether in any case it approximates mill results any more closely than the standard batch test”. It is truly surprising that our classic textbooks promote that locked cycle tests are more art than science, and suggest that they can be of dubious value. None of the textbooks provide meaningful insight or discussion in how to assess:"

Jan 1, 2001

By D. Getzlaf

"Oilfield cementing has been utilized in the industry since the turn of the century. Originally, wells were shallow and criteria for well integrity were somewhat limited. Since that time, wells have stretched the envelope in depth, temperature, and pressure. Environmental regulations have also become more stringent, thus, the importance of hydraulic isolation between permeable zones, and between these zones and surface has become more and more important.Initially, oilfield cements were comprised predominantly of construction cement and very limited additives. As time progressed, additives were incorporated to control pumping time or placement time and little effort was placed on optimizing actual components within the cement chemistry. This paper presents issues and concerns created by adding just one new component to the fundamental chemistry of an oilfield cement."

Jan 1, 2004

By P. D. S. St. Pierre

IN REGENT YEARS, blast furnace operators have found it necessary to improve their technology in order to handle increasingly low-grade feed and yet satisfy the demands for greater tonnages of metal. Studies have been made covering several aspects of the problem, and in this connection the slags produced in the iron-making process have been critically examined with a view to discovering the slag with the optimum properties for a given operation. A good slag should combine, as far as possible, the properties listed in Table I. Unfortunately, some of these desirable properties are incompatible. For example, the advantage of the small ?bulk of a low-flux slag is offset by its low desulphurization potential and high viscosity. Similarly, a very fluid slag increases refractory wear. It will be seen, then, that a balance must he struck between these conflicting requirements. In the .present paper only the melting relationships of blast furnace slag ?compositions will be considered in detail. In interpreting the data herein presented, the optimum property requirements listed in Table 1 must strictly be borne in mind. It should also be noted that the discussion presented here always relates to calcined fluxes, since this facilitates reference to the final slag composition. Thus, in making calculations pertaining to the ?burdening of the furnace, due allowance should ?be made for the fact that the fluxes are added as carbonates.

Jan 1, 1956

By R. Jackman, D. Koningen, G. Wilcox

"Gowest Gold Ltd. is in the process of developing the Frankfield East gold deposit located along the largely undeveloped Pipestone fault northeast of Timmins, Ontario. In addition to resource development and environmental permitting work the company has had an ongoing program of metallurgical and engineering studies aimed at evaluating options for processing the Frankfield East ore. Mineralization at the Frankfield project contains arsenopyrite and pyrite as the major sulphide minerals. Bulk flotation of all sulphides results in extremely high gold recovery. However, the gold is almost entirely associated with the arsenopyrite fraction of the ore and is refractory in nature requiring preoxidation treatment. Selective flotation was investigated to recover a gold-arsenopyrite concentrate thereby reducing the mass which would be subjected to further gold processing. As part of this work, a pyrite concentrate low in arsenic content was also recovered that would be suitable as a source of sulphur for a smelter (or other pyrometallurgical facility). Production of separate arsenopyrite and pyrite concentrates is frequently examined but rarely adopted due to the distribution of gold between the two products or the inability to achieve adequate separation. Several flowsheet options were investigated in the study. The best results were achieved following a sequential flotation flowsheet. The flowsheet configuration was key to meeting the targets for the two products. In this paper, the various options investigated are reviewed and the results of the final flowsheet are presented. The overall plan by Gowest was to evaluate all process options to bring the Frankfield East deposit into production. The ability to effectively separate the arsenopyrite and pyrite components in the ore provides Gowest with added opportunities to pursue both short and long term production scenarios."

Jan 1, 2012

By Richard Jundis

At the Vale Inco Ontario Operations, the working environment is rapidly evolving with organizational changes, new business systems and software tools. These changes are required in order to meet today?s challenging business environment. Mining professionals are focusing on the development of safe and achievable mine plans to maximize mining value while reducing the potential of project delays and production shortfalls. This paper explores how new design tools, techniques and system designs in mine planning are being developed to optimize the value of every ton of ore mined and processed. To differentiate from other papers on long-term planning, this paper focuses on the concept of business planning at the mines. Business planning is the understanding and optimization of the relationship between mine plans and the value it adds in the overall process. The management and key stakeholders of Vale Inco have recognized that the development of a robust mine planning system and programs are essential for the long-term sustainability of the operations.

May 1, 2009