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By M. C. Mound, E. Gallestey, C. Colbert

Continuous operating performance and high profit is one of the major concerns in the mining industry. Information systems are expected to reinforce and enable conformance to these requirements. The companion efforts of business management and production information systems press for tighter integration to avoid over-laps, multiple instances of similar data, and expensive maintenance of databases. Implementation of advanced intelligent systems throughout a mine operation can reduce costs, optimize investment and create a shorter payback via conversion of the data accumulated by field and process devices into information, and subsequently, into decisions. However, in order to harness the potential power inherent in these intelligent devices, adequate and flexible modular knowledge-based solutions are required. Fortunately, there has been at least one such practical response to this challenge, namely the ABB IndustrialIT portfolio. With these tools in place, production efficiency is reached via integration of process, production, and quality information. Moreover, they permit immediate detection and remedial action to changes to process and boundary condition variables. Finally, using advanced optimization techniques supported by dedicated mathematical models, they allow for economic process optimization (process set points and coordination thereof, energy management, production planning, energy supply contract optimization, etc) of the plant as a whole.

Jan 1, 2004

By P. V. Chandramohan

"In ports, piled berths are designed and constructed for berthing of ships with a finite draught. Piles in a bridge foundation also have a large free stand above scoured level. The piles of these structures have to withstand large horizontal forces imparted by the impact of the approaching vessels or due to longitudinal and transverse action in a bridge. It is also imperative that these piles have to project out of the dredged / scoured bed. These piles are normally designed as slender compression members subjected to bending also. They are subjected to vertical load tests for assessing the soil resistance. Lateral load tests, as a rule, are also stipulated. IS and IRC codes stipulate a deflection criteria for lateral load test to arrive at the capacity. These tests are usually conducted on a working pile by jacking out two piles. At the time of the test, pile will be free headed. But in service, piles are fixed head. There is a large difference in deflections between a fixed head and a free headed pile. Besides, a free headed pile will be subjected to a much higher bending moment than the fixed head one. This will put the working test pile under risk of breaking during the test. The problem is analyzed with case studies. INTRODUCTION Vertical capacity of piles is assessed by static formulae. This formula is based on the soil properties obtained from random soil exploration and laboratory and in-situ testing. Since soil is not a homogeneous medium, properties can vary. The design parameters taken for computations may be different from the ones at the interface of the pile with the soil. The best way is to find out is by a load test. The code IRC:78-2014 has rightly stated that initial load test is part of the design process. This is true with the vertical load test. But there are certain problems with the purpose and inference of the lateral load test. In both the tests the criteria for acceptance is the quantum of movement of the point of application of the load. In the former, the movement is vertical and depends more on the compression of the soil than the compressive strain in concrete. But in the latter, this movement is partly on account of the flexural rigidity of the pile and partly due to the horizontal compressibility of the soil. The role of rigidity of the pile is more when compressibility of the soil is higher. Lateral load test is done by jacking one pile against another because it is difficult to get an independent horizontal reaction. Please see Fig.1 Photo."

Jan 1, 2015

TABAKOTO / SEGALA ? Annual gold production approximately 100,000 oz ? Debt free ? Unhedged ? Combined surface reserves 949,000 oz ? Combined 9 year life Tabakoto open pit reserve 568,000 oz (3.4m tonnes @ 5.26 g/t Au) Segala open pit reserve 381,000 oz (3.98m tonnes @ 2.98 g/t Au)

May 1, 2006

By John J. Mulligan

The Bureau of Mines investigated the tin deposits of the Cape Mountain area during July and August 1962 to test the effectiveness of detrital-cover sampling in permafrost areas as a relatively cheap and simple means of guiding mine development and exploration. Results indicate that systematic detrita1-cover sampling can be used effectively to delineate obscure deposits with sufficient accuracy to permit sampling with a minimum of trenching or drilling. Extensions of known outcroppings were traced in sufficient detail to guide lode sampling and several previously unknown tin-bearing lodes were found and sampled. Lode sampling was limited to the minimum needed to establish the reliability of detrital-cover sampling results. The results of previous lode and placer investigations are summarized and detrital-cover sampling methods and results are described in detail.

Jan 1, 1966

By O. C. Blade

The term "Ichtnyol" is a name applied loosely to certain preparations used in pharmacy. These preparations do not occur as such in nature but are manufactured by various chemical processes. Ichthyol is the name trademarked for a product manyfactured by the Irhthyel-Gescllschaft (Cordes Hermanni & Co.) of Hamburg, Germany, and marketed in thin, country by Merck & Co., Inc., (5, 86, 87)3/. Although used in the literature rather loosely, the correctly applied word refers to the product obtained by sulphonating and then neutralizing with ammonia a distillate from the oil retorted from a certain high-sulphur bituminous shale found near the village of Seefeld in the Austrian Tyrol. Due to the fact that fossils of fish and marine animals occur in the limestone associated with the bituminous shale, these deposits have long been known as, the "lchthyolite schistc of Seefeld" ( 55) . The Greek word "ichthys"" for fish and the Latin word "oleum" for oil are the words from which the term is derived. The crude, tarry shale oil, whose distillate is the raw material for the sulphonation process, has been referred to since the Middle Ages as "Dürsten" or "Tirschen" oil, and the term "ichthyel oil" has been used occasionally in the literature to designate the retorted crude oil (92, 93, 106, 117). The first application of the name "Ichthyol" to a particular product is credited to Schröter (35, 129). Various names for products manufactured by sulphonating bituminous distillates have been coined, and in some of these names the root from the word ichthys has been retained. Some of these names can be found in New and Nonofficial Remedies under the heading, Sulphoichthyolate Preparation, and Substitutes (5).

Jan 1, 1938

By Max W. Ball

THE world's largest known oil deposit lies in northern Alberta. In fact, according to government estimates, the famous so-called 'tar sands' of the Athabaska region contain several times as much oil as all the other proved reserves of the world. S. C. Ells, of the Department of Mines and Resources, who has been the Dominion Government's authority on the oil sands since 1913, has estimated the minimum content of the deposits at 100 billion barrels(!). C. P. Bowie, of the U.S. Bureau of Mines, has published an estimate of 250 billion barrels(2). ?In comparison, the latest authoritative estimate of the proved oil-field reserves of the world is less than 35 billion barrels(3). Out of this tremendous total, perhaps 500 million barrels are commercially available at present-day costs and prices; the remainder must be considered a latent reserve to be used when development costs are materially lower and petroleum prices materially higher than they now are. Mean-while, the 500-million-barrel portion presently available contains more oil than has been found in all the rest of Canada, and constitutes one of Canada's great mineral resources. Although these deposits have been known to white men since 1788, when Peter Pond, the explorer, found the Indians stewing the oil out of the sand and mixing it with spruce pitch to caulk their canoes, they are only now coming into commercial production. The purpose of the present paper is to describe the deposits, their oil content, their present development, and the possibilities that seem to lie immediately ahead. For the sake of completeness and clarity, the writer has not hesitated to use or to paraphrase material that he has previously published elsewhere in discussing various aspects of the oil sands.

Jan 1, 1941

By M. Sabau

The Electrowinning Plant at INCO's Copper Cliff Nickel Refinery is a precious metals upgrading plant. The feed to the plant contains copper, nickel, cobalt, iron, significant amounts of precious metals and some impurities. Copper is the most abundant element in the feed. This paper describes the major equipment and process changes over the last twenty years, geared to improve the tankhouse operation, workroom environment and recovery of copper from the acidic solution. Copper is plated on to titanium blanks using explosion-bonded crossrods, animal glue as a levelling agent, and an organic surfactant for mist control. The installation of the stripping machine in 2001 required a number of changes: cathode and anode contacts were redesigned, flat bus bars were replaced with dog-bone type, spacer boards for cathodes and anodes were installed, longer anodes started to be used, and the plating cycle was extended from seven to fourteen days. A number of initiatives for improvement are being carried out. Explosion-bonded crossrods are being replaced with titanium-clad crossrods. The plan for the near future is to increase copper production by increasing current efficiency and current density. The possibility of lowering the iron concentration in electrolyte and changing the acid mist control method is being investigated.

Jan 1, 2007

By L. A. Neumeier

The Bureau of Mines evaluated the properties and anisotropy in properties of rolled Zn-Cu and Zn-0.12 pct Ti-Cu alloys with various copper additions to 1.25 pct. The alloys were rolled cold and at various hot-rolling temperatures to reductions as high as 92 pct after breakdown rolling. The properties are extremely sensitive to various combinations of composition, rolling temperature, and rolling reduction, Zn-Cu alloys can develop good creep resistance, but they are inferior in that respect to Zn-Ti-Cu alloys. For alloys either with or without the titanium addition, cold-rolling results in recrystallization of the matrix and rejection of copper from solution, causing poor hardness, tensile, and creep properties, but high ductility. Peak tensile strengths develop when the alloys are rolled in the range 320° to 400° F, Best creep resistance for Zn-Cu alloys requires higher rolling temperatures when copper content is increased. Creep resistance is best for Zn-Ti-Cu alloys with about 0.75 to 1.0 pct CU rolled near 480° F. Some copper is soluble in the TiZn15 phase, which forms into "stringers" during rolling. The possible contributions to creep behavior of factors such as distribution of second-phase particles, grain size, and preferred orientation are discussed.

Jan 1, 1970

By T. Gerritsen, R. C. Delgado, J. Janzen, E. R. Veloza

The paper describes the components of an Integrated Furnace Control system for covered-arc (shielded arc) smelting with results from the recently started 75 MW Cerro Matoso Line 2 Furnace. The paper starts with a review of the mechanisms of power and feed input and heat losses in the shielded-arc smelting process, and describes how the details of the control system are tailored to the process. The control modules of a covered-arc smelting furnace are described including measured results and screen captures. This paper focuses on Integrated Furnace Controls tailored to shielded-arc smelting, but similar approaches have been recently applied to other furnace processes including immersed-arc smelting.

Jan 1, 2004

By L. Bircumshaw

Paper written on project work carried out in partial fulfilment of BSc (Eng) (Chemical) degree This paper details the formulation of a mathematical model for the simulation of a primary bioleach reactor, with specific reference to the leaching of pyrite. The model is based on the direct reaction mechanism, where the leaching of pyrite is said to occur via a two-step process. The process involves the formation of ferrous?iron through the chemical leaching of pyrite and subsequent bacterial oxidation of ferrous-iron back into ferric-iron. At steady state the rate of chemical leaching and bacterial oxidation are linked by the ratio of ferrous-iron to ferric-iron in solution. The extent of conversion of pyrite in the reactor system is described using the segregated flow model, with the exit age distribution of the solid phase being described by the Tanks-in-Series model. The final phase in model formulation involves the inclusion of steady state material balances on the bacteria and fluid phase components. The model is compared to pilot plant data and laboratory data for two different types of pyrite concentrates, with simulation results showing that the model is in good agreement with the data. Author key words: Bioleaching; pyrite; primary reactor; modeling; segregated-flow model; tanks-in series model.

Jan 1, 2006

By A. W. Deurbrouck

Five preparation plants employing concentrating tables for washing 3/8- inch to 0 raw coal were tested. Two of the plants were washing Pittsburgh-bed coal, two were washing Pocahontas-bed coal, and one was washing Elkhorn-bed coal. Samples of the feed to and products from the tables were collected over the normal operating shift. These samples were analyzed, and complete performance criteria were determined. The results of this study show that the concentrating table is an effective fine-coal cleaner even when operating at 40 percent over the recommended 10 tons per hour feed rate. Recovery efficiencies for the 3/8-inch to 200- mesh size fraction ranged from 97.3 to 99.3 percent; maximum yield errors and ash errors were 2.4 and 1.0 percent, respectively; probable errors ranged from 0.074 to 0.115 specific gravity units and error areas from 52 to 73 square centimeters. The amount of minus 200-mesh material in the water used for feed water and dressing water to the table had no significant effect on the sharpness of the separation achieved but did have an effect on the ash content of the clean- coal product. In the one plant studied, the substitution of fresh water for plant circulating water reduced the ash content of the clean coal by about 6 percentage points.

Jan 1, 1963

By A. Putz, F. Vincent, A. R. Laplante

"This paper briefly reviews some of the gravity research done at McGill University and current Canadian operating practices, with emphasis on results of interest for operators. The following topics are addressed: security, economics, predicting recovery, circuit optimization, unit selection and final upgrading. Emphasis is placed on the Knelson Concentrator.The topic of security and economics are addressed jointly, in terms of the place of the gravity circuit in the mill flowsheet. Actual plant experience is drawn upon to identify potential problems and actual solutions.Predicting primary recovery is linked with a characterization of the ore, the choice of a circuit, and the fraction of the bleed used. Factors such as feed preparation, preliminary upgrading, fraction of recycle treated, ability to recover fines and location of the bleed are discussed.Final upgrading is achieved almost only by tabling and smelting. This can lead to fine gold recovery problems when more effective units are used upstream. Alternatives are discussed.IntroductionResearch on gold recovery by gravity over the past eight years has associated McGill University with a number of gold producers. This paper attempts to review the information gathered from a practical perspective. Some of the information was generated in McGill University's labs, some gathered at plant site, and some was shared by operators."

Jan 1, 1994

By G. E. Tooker

This paper (1) presents new data on the use of horizontal curves to optimize the alignment of belt conveyors. The operating concept of a horizontal curve is simple. As an element of the belt passes through the curve, it is motivated to drift toward the center of the curve by unbalanced tension forces in the belt. This lateral drift is resisted by the forces of friction and gravity, which in turn can be stated as a function of drift. Resisting forces, as a function of drift, are stated in terms of variables such as the amount of load on the belt, and parameters such as the trough angle, tilt angle, and super elevation angle, and number of rolls in the idler. The trick is to determine that the belt will drift to a position of equilibrium within predictable limits, without physically constraining the edge of the belt. In practice this prediction is not easy to make without the aid of a computer. The motivating force is easy to calculate, but its value is continually changing throughout the angle subtended by the curve arc. The resisting forces are constant throughout the curve for a given drift and load condition, but the calculations are very complex. Data in this paper will assist the conveyor designer in making preliminary calculations for horizontal curves. Presented is the equation for calculating the motivating force, and a family of curves that show the resisting force as a function of lateral drift for some commonly encountered conveyor design criteria.

Jan 1, 1985

By C. Jackson, J. J. Harrington

The pH control system at Kennecott Copper Corporation's Nevada Mines Division concentrator consists of two independent systems, lime dilution and lime addition. Lime dilution is accomplished in a mixing tank where slaked lime and water are introduced proportionately. The desired dilution of the milk of lime is determined by the electrical inputs provided by eight pH probes, one per grinding section. The inputs are averaged and applied to a time base generator. The summation output of the time base generator determines the proportion of lime and water that are to be mixed and applies this input to a voltage sensitive switching device. The switching device provides a signal to one of two relays which will add either slaked lime or water, dependent upon the summation output. The entire cycle is based on a 2-min repetition rate to allow for sufficient mix time. Responsivity is controlled by maintaing a limited maximum solution level in the mix tank. Lime addition is controlled independently within each grinding section. The electrical input from the pH probe in a given section controls the solenoid valves which provide lime to each of the ball mills. The valves remain open within a time range capable of maintaining the pH of flotation feed at a given set point.

Jan 1, 1978

By Mohammed Sakr

A Two-Section Helical Pile (TSHP) is a steel pipe with two shaft sections of different diameters and with one or more helix plates near the bottom of each shaft section. TSHPs are used regularly in western Canada as foundation pockets for single and double circuit distribution power line poles. The results of a comprehensive lateral pile load test program and the field monitoring of TSHPs installed in organic soil (muskeg) over soft clay are presented in this paper. A total of nine full scale lateral load tests were carried out, including seven tests using TSHPs with different diameters and embedment depths, and two tests using one-section helical piles. The prime objective of the study was to evaluate the lateral resistance of TSHPs installed into very soft organic soil (muskeg) overlying soft clay soils, to compare their lateral resistance relative to one-section helical piles and to compare the measured and the estimated lateral resistances using p-y curves. In order to provide sufficient soil data for analysis, the subsurface soil stratification was evaluated using two different techniques including; Cone Penetration Tests (CPT) and Portable Soil Probe Tests (PSPT). The two testing techniques were also compared and evaluated. This paper summarizes subsurface soil conditions, pile configuration, helical pile installation procedure, testing setup and results.

Jan 1, 2009

By T. A. Klinefelter

KYANITE and the related minerals sillimanite, andalusite, dumortierite, and topaz are natural aluminum silicates that can be used in production of mullite (3A1203?2Si02), a superduty refractory material. Kyanite and sillimanite are the dominant ones because of their greater abundance. The only other kyanite-group mineral presently used for mullite production is andalusite. Mullite is not an absolutely essential material as other refractories can be used in the same heat range. However, it is a highly satisfactory one. It is the only compound of silica and alumina that is stable at high temperatures. It has low thermal expansion and is very resistant to corrosive melts and to thermal shock. For these reasons mullite refractories have a much longer life than standard fire-clay refractories under the same conditions. Worldwide, excluding U.S.S.R., the refractories industry consumes about 150-000 short tons annually of kyanite group minerals and synthetic mullite.

Jan 1, 1961

The Montgary pegmatite is located at Bernic Lake in the southeastern Manitoba pegmatite district. 'It has a complex internal structure with several contrasting mineral assemblages. The pegmatite contains a number of potentially valuable miners including spodumene, amblygonite,. lepidolite, zinnwaidite, pollucite and beryl.. The distribution of each of these within the pegmatite is related to the internal structure and controlled by a specific mineral assemblage. Parts of the pegmatite contain a high concentration of spodumene. The pollucite occurrence is of unique character and is one of the largest known deposits of this mineral. The pegmatite is still-like in attitude with a maximum dip of about 15 degrees. Its contents with the amphibolitic wall rocks are sharp and tourmalinized. Mineral assemblages present include perthite-plagioclase-quartz-muscovite, spodumene-microcline perthite-plagioclase-quartz-muscovite, cleavelandite-lithia micas-quartz, quartz-amblygonite, albite, lepidolite, pollucite, and quartz assemblages. The occurrence and relationships of these are described and possible relationships between attitude and internal structure are discussed. Many features of the pegmatite suggest that the deposit formed by crystallization and differentiation of a pegmatitic fluid in a restricted system. These features are discussed. The nature and occurrence of the pollucite, lepidolite and albite assemblages are such, however that it is difficult to visualize them resulting from such a system. These assemblages may be of later replacement origin. The source of the, late, alkali-rich replacing solutions may be unmixing of soda and the rarer alkalis (lithium, rubidium, caesium) from earlier-formed silicates in a manner analogous to the unmixing of soda feldspar in perthites. Various aspects of this hypothesis are examined.

Jan 1, 1959

By Edward H. Jr. Boyle, Paul R. Thomas

Introduction It is estimated that nearly 40% of all the gold ever mined in free world countries has been produced by South African operations. There is concern that this immense productive capacity will soon decline. Such a decline could reduce world gold supply and lessen the ability of market economy countries (MEC) to exert the major influence upon the world gold market. This paper addresses three general issues concerning South African gold production: • How much gold remains to be recovered from the demonstrated resources of the 44 evaluated South African mines; • How long can production at current levels continue; and • What will be its cost. Table 1 provides production data on the world's 10 largest producers for the years 1971, 1981, and 1983. As shown, South African gold production declined significantly from 1971 through 1981. As of 1981, annual South African gold production had dropped by more than 311 t (10 million oz) in 10 years. Despite this, its mines still produced 656 t (21 million oz) that year, about half the world total. From 1981 through 1983, this trend was reversed. Annual South African gold production increased by more than 21.8 t (700,000 oz). The trend reversal was also evident in the US, Canada, and Australia. This illustrates the general, inverse relationship between gold price and gold production. In South Africa especially, as gold prices increased substantially during the 1970s, the average grade of ore mined (pay limit) was lowered as new, lower grade areas and materials were exploited. Gold production declined in volume. But gold revenues increased, and the lives of the operations were extended. The 1981-83 period was one of declining (US dollar-based, average annual) gold prices that resulted in increasing South African production as average ore grades were raised. South Africa currently accounts for 50% of world production (Fig. 1). Figure 2 illustrates South Africa's contribution to total MEC production in 1971 and 1983. Although South Africa's relative share of production has declined, it still represents the single most important source of new gold supply. In 1983, it supplied more than 65% of total MEC production. South Africa currently produces more than twice as much gold as the Soviet Union (ranked second in world production), and 11 times more gold than the US (ranked fourth in world production). Barring major discoveries, South African gold production is expected to peak in 1987 and begin to decline again throughout the 1990s. The rate of decline is ex-

Jan 11, 1984

The recent paper by Dr. Edwards upon the copper deposits of Australia furnishes a perspective upon that portion of the Commonwealth's mineral deposits which is the more welcome because it has been long overdue. The paper yields in compressed form and in handy arrangement for reference the more relevant data to end of 1938 for all of Australia's important copper deposits 'past"and. present, and for many of the lesser ones. The information supplied 'obviously' has 15een collected' painstakingly and compiled with discrimination.Such published surveys of a national character have been far too few.The Mineral Resources Survey branch of the Department of Supply and Shipping at Canberra has been engaged for several years upon comprehensive compilations of data concerning each of the more important minerals used in industry. Presumably the results will be published after the war. The group will constitute an impressive and valuable series.As yet the work has not been completed, and, for security reasons, much of that which has been finalized is not publicly available. This makes the paper by Dr. Edwards the more timely.In the compilation of data by those not acquainted at first hand with many of the districts involved it is inevitable that, from reading of the literature alone, certain misconceptions will arise relationships become confused; and some of the more recently acquired information unavoidably fail to be taken into account. One need only compare his own impressions of a district, gained from reading the published literature prior to inspection, with the impressions later arrived at following a visit, to realize the difficulties in appraising the various features,in their proper relationships.On the whole, Dr. Edwards has, kept such misinterpretations at a minimum, which is a tribute to the care he must have exercised in analysing the vast fund of data perused. A few errors of statement, mainly concerning, Queensland deposits, have been noted. None is vital, but in the interests of accuracy it seems well to point them out.QUEENSLANDMount IsaOn page 108 Mount Isa's prospective output of 12,000 tons of copper per year is stated as coming from the Doherty section (O'Doherty, Black Rock mine, R.B.),- the copper ore-body is said to occur in dolomitic limestone (-Page 110)-, and Mount Isa's copper output for 1938 from that source is given as 22 tons. On page 145 the same prospective copper output is stated as coming from a body lying out in the hanging-wall of the silver-lead-zinc...

Jan 1, 1943

By H. V. Makar

Ferrous fractions recovered from urban refuse were tested by the U.S. Bureau of Mines, U.S. Department of the Interior, to assess their character, composition, and response to detinning. This research was conducted as part of the Bureau's efforts to conserve mineral resources through recycling. Results from laboratory and pilot tests established the technical feasibility of detinning scrap recovered from household refuse. Detinned products containing less than 0.03 percent residual tin were produced. Concentrations of other residual elements were determined and compared with those in existing commercial scrap and with proposed specifications. Studies were extended to include evaluations under commercial conditions. Preliminary tests on 5-1/2 short tons of ferrous fractions revealed the need for adequate shredding to assure optimum metal-caustic contact and minimize retention of tin-bearing rinse solution in the final baled product. The washed metal product contained 0.06 percent residual tin. Subsequent melt tests showed a yield of 91.4 percent. Based on these studies, full-scale commercial demonstrations showed that detinned bales equivalent to No. 1 bundle quality could be produced in carload quantities. Up to 5 pounds of tin per gross ton of scrap is con-currently recovered during the detinning process.

Jan 1, 1979