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The Santa Rita mine is located in north eastern part of Bahia in Brazil and is owned and operated by Mirabela Mineração do Brasil Ltda. Typical SABC circuit was designed as the preferred option for the 4.0 mtpa (500tph) to produce a P80 of 125um for flotation. Although the SAG was originally designed to operate with conventional radial pulp lifters, later it was fitted with Outotec?s Turbo Pulp Lifters ? TPL (Latchireddi, 2005). The milling circuit commenced commissioning on the 24th of October 2009 and the milling circuit achieved the nameplate capacity within days. with small and relatively simple measures to rectify. Since commissioning, the SAG mill has been working in fully autogenous grinding (FAG) mode with no balls (in contrast to the estimated 10% ball charge) and has been consistently treated up to 650tph. This paper examines the comminution design process, the operating philosophies, start-up experiences, post commissioning optimization and future development works. An evaluation of mill performance relative to the design criteria for the project life to date is also included.

Jan 1, 2012

By N. Parnian

"Carryover of caustic soda (NaOH) in the steam path caused catastrophic failure of superheater 304H stainless steel tubes in a steam generator and led to an unexpected shutdown after just five months of continuous service of petrochemical following the start of production. The cause of the failure was studied, with a focus on the formation of sigma phase in the weld joint and effect of caustic embrittlement on stress corrosion cracking (SCC). The cracks were examined at the seam weld, heat affected zone (HAZ), and Ubend areas. Hardness was measured for the base metal, HAZ, and weld metal, and microstructures were examined using optical microscopy and scanning electron microscopy (SEM). Crack initiation is attributed to gouging on the precipitated carbide at the HAZ and also the formation of sigma phase in the weld metal, as shown by energy dispersive X-ray (EDX) analysis. In addition, cracking was propagated by caustic embrittlement because of residual stresses and hammering. Finally, the characteristic feature of fracture was illustrated by SEM fractography, and consists mostly of intergranular SCC and some quasicleavage transgranular. INTRODUCTIONThree key factors are needed for the initiation and propagation of intergranular stress corrosion cracking (IGSCC): a susceptible material, a corrosive environment, and sufficient stress. Although austenitic stainless steels are susceptible to sensitization and IGSCC, they are widely used in boiler and superheater tubes because of their high corrosion resistance, high oxidation resistance, acceptable mechanical characteristics at elevated temperatures, and low cost.Sodium hydroxide is injected to neutralize acidic constituents in the steam path, but caustic can concentrate in boiler tubes and attack the surface metal (known as gouging) even traces of caustic in the steam can deposit on surfaces and cause local concentrations of several percent (ASM handbook, 1992). Not only sensitized grains but also sigma phase formed in the weld metal can initiate caustic cracking. In this research, the cause of the failure of 304H stainless steel superheater tubes in a methanol petrochemical plant in Iran was studied with a focus on the effects of caustic embrittlement on IGSCC."

Jan 1, 2012

By J. F. Davis

Pegmatite dykes containing lithium minerals and beryl occur dose to the borders of intrusive masses of granitic rock in the Winnipeg River area of Manitoba. Both vertical and flat-lying dykes are present. Most of the pegmatites consist of zones, containing characteristic mineral assemblages, arranged more or Jess parallel to the borders of the dykes. Five important lithium minerals are present; each occurs in a separate zone, but all the lithium-bearing zones are situated toward the centres of the pegmatites. Spodumene is the most abundant and widespread of the lithium minerals and occurs as small crystals intimately intergrown with quartz. Beryl is not an important constituent of the lithium pegmatites, but when .present, occurs outside the lithium zones, toward the margins of the -dykes. Beryl is most common in dykes containing few or no lithium minerals. The mineral assemblage in the beryl zone of the lithium dykes is the same as that of the beryl dykes. The attitude and internal structure, particularly zoning, of the pegmatite dykes, and the texture and assemblages of the constituent minerals, have an important bearing on exploration, development, and mining of these pegmatites, and on the extraction of various mineral products from them.

Jan 1, 1958

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 T. S. Smith

INTRODUCTION IN PREPARING this paper for the District 4 Meeting, three factors had to be considered. First, the paper must fit the time alloted; second, it must give a general picture of the geology for those unfamiliar with the property; and third, it must contain some new material in order to be of interest to local delegates. The most comprehensive extant discussion of the geology of the property of McKenzie Red Lake Gold Mines, Limited, is contained in Horwood's report on the general Red Lake area ( 1). This report is the 'bible' of the area, and a general paper on the geology of this particular mine would almost certainly appear to be a condensation of it. It was thought, therefore, that the most suitable procedure would be to base the general outline on Horwood' s report, to extend that outline where possible from information gained since its publication, and finally to leave dangling for the contemplative geologist some of the ideas and problems which ?are currently under consideration. LOCATION AND HISTORY The property of McKenzie Red Lake Gold Mines, Limited, is in Dome township, in the Red Lake mining division of northwestern Ontario. The mine is on McKenzie Island, about four miles north, by water, of the Hasaga mine and old Howey mine.

Jan 1, 1951

Of the twelve known ore zones on the Sunro property, acquired by Cowichan Copper Co., only the "B" and "C" orebodies of the "River Zone" had been explored sufficiently to indicate the grade and tonnage. The "B" zone was selected for initial production. The portion of this orebody above the main adit level was developed for horizontal-ring, longhole mining. Ore from the stope would be scraped directly to the coarse ore bin. The lack of a suitable mill site on surface, as well as the 8,000-ft. tramming distance, led naturally to the installation ground. I N November, 1960, a lease was obtained by Co-wichan Copper Co. Ltd. (N.P.L.) from Sunro Mines Ltd., covering the main ore (River) zone of the Sunro property. A total of twelve zones had been located on the property. Nine of these lay within the leased area. With the exception of the "B" and "C" orebodies of the River Zone, there had been insufficient exploration for tonnage and grade calculations. Exploration by previous companies had

Jan 1, 1965

By B. R. Boardman

Project Environmental Approval is a multi-faceted issue. From a mining perspective, it is a costly item because of avoidable time delay. The government perspective is that the approvals are a necessary part of meeting departmental requirements to ensure that the wellbeing of other uses of the environment is maintained. This paper outlines some of the problems inherent in the environmental approvals process and makes recommendations to both the proponent and government about improving the efficiency of the process.

Jan 1, 1978

By J-g. Cui, X-b. Guo, J-j. Wang, J. Qiao, H. Tian

"Rare earth elements have unique properties because of the special electronic structure. In this paper the improvement of refractory material performance by the light rare earth oxides was introduced. The experiments showed that adding a bit of rare earth oxide could obviously improve the performance of the refractory material. INTRODUCTIONIn recent years, refractory materials are widely applied in the steel smelting process as a ladle lining material. In China, although the total production of fire-proof material exceeds normal demand, but the quality and variety of fire-proof material still have a big gap with world advanced level. A number of refractory products need to be imported from abroad. With the rapid development of domestic steel production, the ladle lining with refractory is gradually running after the world advanced level on production technology, production variety, and quality level. It replaces some imported products meeting the needs of the development of the iron making production. Therefore, there is an important significance to research on solving the problems of the ladle refractory reasonably and avoiding or reducing blind and not proper use of the imported refractory ( Jing, 2007).On the other hand, rare earth oxide has some special excellent properties. Firstly, they are very good refractory materials with their high melting point;Next, they have good resistance to water and alkali resistance function;Thirdly, it is easy for rare earth oxide to generated composite oxide reacting with other metal oxide,achieving the purpose to improving the material properties (Xu, 1978; Diao, 1979). China has a variety of rare earth resources,and rare earth resources is more advantageous in Baotou,taking up about 36 percent of world reserves,which is the world's top of rare earth mineral. In recent years the rare earth products output has risen sharply and many varieties and specifications have appeared. So it is necessary to study the new field of rare earth compound to open up new markets. Thus, it has a very vital significance to promote the further development of rare earth industry, adjust the rare earth products structure, ease the contradiction between supply and demand, and improve refractory products quality and grade in order to better serve the main body production.I In this paper, the experiments are mainly for 210 tons of Al2O3-MgO style series refractory materials belong to ladle lining bag from Baotou Iron & Steel Group Corporation Sheet Factory. The improvement to the effect of refractory material performance is explored by using light rare earth oxides as additives."

Jan 1, 2012

By Gaston Gendreau, Marcel Allard

"Sidbec-Normines Inc. est une société formée de trios partenaires soient: Sidbec, British Steel Corporation et la Compagnie Minière Quebec Cartier. L'objectif de l'opération minière est d'exploiter à ciel ouvert le gisement d'hématite spéculaire de Fire Lake et de produire au concentrateur de Lac-Jeannine, près de la ville de Gagnon, 6 million de tonnes de concentré pour alimenter l'usine de bouletage de Port Cartier.Le présent exposé a pour but de fa ire ressortier les caractéristiques d'une opération dont la mine est située à plus de 100 km du concentrateur, d'en faire ressortir les particularités touchant le transport du personnel et du minerai. En plus, on traitera de l'importance dans une telle situation d'une organisation efficace dans la gestion des services et de l'opération (atelier, concasseur, entrepôt, etc.).IntroductionSidbec-Normines Inc . a entrepris l'exploitation minière du gisement de Fire Lake, le 1er janvier 1977. Le but de l'entreprise est de produire annuellement six millions (6 000 000) de tonnes de concentré d'hématite (oxide de fer) titrant 66% Fe au concentrateur de Lac-Jeannine a partir d'un minerai d'une teneur moyenne de 33% Fe, extrait de la mine de Fire Lake. Ce concentré est ensuite achemine à Port-Cartier et alimente I'usine de bouletage.Les installations minières de Sidbec-Normines sont situées a trois endroits différents : la mine à Fire Lake, le concentrateur à Lac-Jeannine et l'usine de bouletage à Port-Cartier. La mine de Fire Lake se situe à 83 km de la ville de Gagnon et à 100 km du concentrateur de Lac-Jeannine. Une route provinciale relie la ville à la mine et au concentrateur. Le minerai est acheminé de la mine au concentrateur par chemin de fer et le concentré est transporté par train sur une distance de 309 km à l'usine de bouletage de Port-Cartier."

Jan 1, 1982

By Ian M. F. Arnold

"Occupational health programs and their role in improving the quality of working life in the mining industry are discussed. Attention is directed to some problems peculiar to the Canadian mining industry. Factors affecting program development are reviewed, as well as parameters affecting cost-benefit analyses.IntroductionThe quality of working life in the mining industry is a more important consideration than in many other industrial environments because of the very nature of the undertaking. It was a strange paradox of the 1960s that preventive maintenance programs for machinery and equipment were well accepted, whereas the concept of ""preventive people medicine"" was basically ignored. Fortunately, there seems to be a swing toward the development of occupational health programs in many sectors of the business community; however, there is a noticeable lack of consistency and uniformity for thought among the members of the mining industry. The blame for this lack o f progress in the occupational field cannot be entirely attributed to the industry, but must also rest with (for the most part) apathetic and inadequately trained physicians. This latter problem is slowly improving with the growing recognition that a well-planned and executed occupational health program may improve the quality of working life for mining employees and their families.There are a number of factors which relate to occupational health in mining, and its effect on working life quality. Included among these are:1. Community isolation.2. High accident risks.3. Occupational disease risks.4. Production demands and the state of the economy.5. Government regulatory requirements.6. Travel demands.These, and others, reflect on all levels of the mining industry. To examine how these factors can be moderated by an occupational health program, it is necessary to first review the rationale for such a program and some of the costs related to it."

Jan 1, 1983

By M. Hitch, M. B. Lytle

Resource development conflicts arise largely due to differences in worldview between those who support and those who oppose development. This paper illustrates how societies and civilizations with different worldviews produce different levels of creative and economic energy. A questionnaire was created to build a database of responses to test whether worldview and resource development are correlated. Factor and multivariate regression analysis determined correlations for respondent groupings. Results showed a positive correlation between the respondents\u2019 worldviews and their attitudes toward resource development. Correlations became stronger as the homogeneity of the sample subgroups increased.

Jan 1, 2017

By Atul Bhatnagar, M. P. Sinha, Md Zahid Ahmad, Pallav Garg, Sanjay Kumar Singh, Shashi Ranjan, An Ecolab Company Nalco Water

"Froth Flotation is undoubtedly one of the most critical processes in coking coal washing plants. This work was carried out at Bhelatand Coal Preparation Plant of Tata Steel was with an objective of cost optimization in fine coal processing. The sources of raw coal for the plant include coal from underground mines of Jharia coalfield and procured open-cast raw coal. Coal from different sources vary in quality and possess different floatability characteristics.Synthetic collector is being used in plant as a flotation reagent. An alternate collector with new chemistry was developed for reducing total treatment cost without compromising product yield and quality. A series of laboratory tests were conducted to assess the performance of various sources of raw coal and plant scale trial was started. At first, the new generation coal collector was entirely substituted with the existing collector in the laboratory scale. However the plant scale trial data was not in accordance with laboratory results and indicated inferior flotation performanceThe issue was studied and data based conclusions were drawn that the new generation collector aids faster and uncontrollable kinetics. A decision was taken for co-dosing of the synthetic and new collector for the second phase of the trial. A detailed laboratory analysis was done again and few dosing ratios that predicted optimum results were selected for plant trial. The dosing ratio was optimised as per flotation yield and product ashes during the plant trial. The results showed significant improvement from the first phase and optimum dosing rates were decided based on plant observations and data collection. The influence of various process indicators including water quality, feed and product ashes and process yield was studied during all the trials and promising results were established. The co-dosing of both the collectors conferred cost advantage and enabled to achieve superior performance."

Jan 1, 2016

By G. Scott Zimmer

Mine planning at Cassiar consists of an annual cycle of projection, control, evaluation and revision following completion of annual diamond drilling during the summer months . The inherent difficulty in evaluating fibre grade and distribution, combined with a high-wall phase or push-back mining system, requires continuous modification to designs and schedules based on a cumulative evaluation of equipment performance and prediction versus production. To expedite the planning sequence, a mini-computer system has been introduced which allows emphasis to be placed on optimizing designs, exempting personnel from manual calculations and tabulations.

Jan 1, 1978

By Frank W. Cole, Sharanjit S. Dhillonn

A new method has been developed for calculating flowing bottom hole pressure in a gas well, using as a basis the general energy equation. Fundamentally, the method shows that a plot of flowing pressure versus depth for a gas well can be represented as a series of incremental .straight lines, with the accuracy in-creasing as the number of increments increase. It is shown mathematically that for most cases the slope of the flowing pressure versus depth curve is essentially constant, in which case a single calculation based on surface conditions will yield acceptable results. In all cases studied no more than two iterations were required for very good accuracy, and in most cases only one iteration was necessary. Several example calculations are shown and the results are compared to other commonly used methods of calculating bottom hole pressures These examples show that the method provides answers which are at least as accurate as other methods usually used, and results in a considerable reduction in computation time.

Jan 1, 1960

By Karl J. C. Harries

"The following is an outline or check sheet of some things that might be looked at when considering the concept of a royalty or royalty provisions. It is not intended as a guide to what is right or wrong (that is for the parties to decide). It does not replace the discussions in this work and is not intended to be a complete or exhaustive compilation of matters to be considered. It presumes that you are familiar with the basic concepts of royalties and has been included as an aide memoire only. Use it as such, with caution and common sense, and amend it to suit your needs. Remember also that brevity can result in inaccuracy or imprecision. This is a danger in many points below.The section references are for the sections where the matter is the main subject of the section – see the index for other sections.Royalty TypesNet Proceeds [§§ 5.8.; 11.4.]• No accepted or understood meaning within industry.• Literal meaning, if not defined, would imply “net operating profit”.• Often defined as net profit with revenue base of proceeds from sale of product.• Should not be used without detailed and clear definition. Net Operating Profit [§§ 5.8.; 11.4. – referred to only]• Net profit without recoupment of pre-production expenditures.• Revenue base: usually proceeds from sale of product.• Operating costs deductible.• Some reserves may be permitted.• Recoupment of some post-production capital expenditures may be permitted.• Not often seen as basis for royalties in Canada."

Jan 1, 2003

By Morris J. Viljoen, Young. David R.

"Abstract -The zone of economic interest at H.J . Joel Gold Mine is the VS5/Beatrix Composite Reef, a quartz-pebble conglomerate of Archean age. The reef occurs at the base of the Eldorado Formation, Central Rand Group, of the Witwatersrand Supergroup. At !east three stratigraphically distinct conglomerates form this economic zone. In order of deposition these are the Footwall, Beatrix, and the VS5/Beatrix reefs. The Footwall and Beatrix reefs are equated with the Aandenk Formation with transport directions toward the northwest, whereas the VS5/Beatrix Reef is of Eldorado age, with transport directions toward the south. The change in the drainage direction was caused by a major basin-wide tectonic event that occurred prior to the deposition of the Eldorado Formation. The Beatrix Reef was formed in a proximal, braided, fluvial environment by a process of aggrading gravel bars between channelways. The VS5/Beatrix Reef was formed by the desegregation of pre-existing Beatrix Reef with the introduction of new material containing much shale detritus and is seen to have been deposited in a more ·distal, braided, fluvial environment, similar to the Beatrix Reef.The average gold concentrations are different for each conglomerate; the Beatrix at 32.1 ppm Au, the Footwall at 24.4 ppm Au, and the VS5/Beatrix at only 12.4 ppm Au. A sedimentary gold concentrating process related to higher energy braid channels was primarily responsible for these high gold grades. Not only the basal unconformity surface, but also, internal degredation surfaces, were prime sites for concentration. An understanding of the spatial distribution of these differing conglomerates and their braid channels forming the economic reef zone is necessary in predicting ore grades for future mining."

Jan 1, 1994

By H. H. Bleakney

The merit of reduction-in-area as a criterion of quality in metals is shown to lie in its influence on breaking stress, but the virtue of elongation is not easy to find. In order to assess the value of elongation, either as a measure of quality or as a guide to design, it will be necessary to separate the overall de-formation occurring in tension tests from the localized deformation associated with localized reduction in area. The obstacles to a successful solution of this problem have been shown to be more formidable than is generally appreciated, and a new solution to the problem has been suggested. This solution involves a de-vice by which an electric circuit is broken when the particular value of strain is reached that is to be taken as the point of separation between general and localized deformation. The report presents results from a number of tests on both low-carbon and alloy steels. These results indicate that the selected criterion of separation is accurately identified by the proposed method; that it

Jan 1, 1962

By A. I. Collins, D. Danninger

Newmont has installed advanced control and online optimization on the dry grinding circuit and both roasters on its Carlin Trend refractory ore treatment plant. Subsequently, Newmont has developed a master plan for institutionalizing advanced control and optimization on all its processing units. Newmont is committed to a program of applying advanced control and optimization from crushing of ore to pouring of gold. This paper describes Newmont's experience with implementing advanced control and optimization and the benefits received. In addition, identification of advanced control and optimization opportunities and their economic justification is discussed.

Jan 1, 2005

By Roorda H. J, R. R. Saddington, Curlook W

THE copper-nickel sulfide ore deposits of the International Nickel Company of Canada, Limited contain the minerals pyrrhotite, pentlandite, and chalcopyrite. In the extraction of the nickel, copper, and iron, much of the processing involves oxidation of the metals as well as sulfur. Roasting plays a predominant role at several stages in the operations which prepare the constituent metals for refining. Copper, nickel and iron concentrates of various grades, ranging from low-grade nickeliferous pyrrhotite to high-grade nickel sulfide, must be partially or completely oxidized. Figure 1 shows the main points at which roasting is conducted at INCO. Roasting experience at INCO dates back to the time when lump ore was partially roasted in heaps. It has progressed through single hearth roasters, sinter machines, multiple-hearth roasters, flash roasters, and more recently has centered on the development and utilization of fluid bed roasters. The primitive, slow, and inefficient method of heap

Jan 1, 1961

By Victor F. Hollister, Robert W. Hodder

"The petrology and mineralogy of porphyry copper deposits are thoroughly described in recent literature and cited as the definitive characteristics for this type of deposit. The magmatic-hydrothermal aspect of genesis is also dealt with in detail. However, descriptions of their internal structure and regional setting are not as rigorous, and the genesis of this structure is simply stated as the release of high fluid pressures in a cooling magma emplaced along large fault zones. Genetic relationships between internal structure, regional setting and the tectonic evolution of continents has been alluded to infrequently in the past, but can now be considered together within the developing concept of orogeny at the margins of drifting crustal plates.Tensional structures, on both local and regional scale, and a Triassic to Tertiary age are described for porphyry copper deposits. We contend that such structure and age are distinct and unifying characteristics for this type of deposit and are genetically related to major crustal movements. British Columbia has porphyry copper deposits contemporaneous with plutons 180 to 200 million years old and 40 to 60 million years old. The former age group correlates with early stages of the continent's westward drift, and the latter group with a change in tectonic style during late development of the Canadian Cordillera. Hence, one can in British Columbia reflect on the genesis of a deposit's structure in the broader context of tectonic evolution. Such consideration should lead to more definitive criteria for area selection in exploration."

Jan 1, 1972