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Hamersley Iron Pty. Limited mines and pro cesses iron ore from two orebodies at Tom Price and Paraburdoo, situated in the North West of Western Australia. Conventional open pit mining methods are used at both sites in that material is drilled and blasted in benches, loaded by shovels and hauled to the Primary Crushers or dumped on waste or low grade material stockpiles. The present drilling fleet, consisting of eight high capacity Bucyrus Erie Rotary drills has evolved from an initial fleet of a large number of small percussion rigs. There are significant physical differences between the ore types encountered at both mines which nec- essitate the drilling of smaller diameter blast holes at Paraburdoo than those at Tom Price. The drilling practice at each site is dis- cussed, with examples of performance achieve- ments under varying drilling conditions.

Jan 1, 1978

By D. J. McCracken

During 1995, the estimated consumption of lithium minerals in the western world was 139 kt (153,000 st).This amounted to 18 kt (20,000 st) of lithium carbonate equivalent (LCE). Overall tonnage demand for lithium minerals increased by 10.8 kt (11,900 st) during 1995from 1994. From 1992 to 1995, overall tonnage demand has increased 62%, from 85.5 to 139 kt (94,240 st). There are four major producers of lithium minerals. Gwalia Consolidated in Western Australia is the largest producer of spodumene. It supplies high-grade spodumene concentrate, fine-spodumene concentrate, glass-grade spodumene and chemical-grade spodumene.Tantalum Mining (Tanco) of Manitoba, Canada, produces high-grade spodumene concentrate, fine-spodumene, concentrate and montebrasite. Bikita Minerals in Zimbabwe is the largest manufacturer of petalite. It supplies high-grade and container-glass petalite.

Jan 1, 1996

By Gregory O, Winters BI, Garlick C, Rogers H, Ye ZC

BHP New Zealand Steel produces iron from titaniferous ironsand by a direct reduction process comprising multi- hearth furnaces/rotary kilns/electric iron melters. The electric iron melter is a six-in-line rectangular submerged-arc furnace which takes the partially reduced ironsand (80% metallization) from the rotary kiln and completes the reduction process to produce iron of nominally 3% carbon. As the melter operates at around 1500 ¦C and under very hostile conditions, it is near-impossible to obtain any basic operating parameters such as the velocity and temperature distribution in the slag and in the molten iron. As a first attempt to understand the operating conditions inside the melter, a scaled room-temperature model using wax and water to represent the slag and iron, was constructed. This paper will report on some of the preliminary model results on the temperature distribution.

Jan 1, 1995

By J. David Lowell

For the first time in several years, Chile is again opening its doors to foreign investment. In its new investment code, the Chilean government has announced its willingness to become a partner in joint Chilean-foreign projects for a number of government-controlled porphyry copper deposits at the developed, semi-developed, or prospect stage; and, that it will allow privately owned deposits or deposits discovered by new exploration to be developed with up to 100% foreign ownership. Three deposits of particular interest are: El Abra, with at least 300 million mt of +100% Cu; Los Pelambres, with at least 428 million mt of 0.78% Cu and 0.03% Mo; and Andacollo, with 350 million mt of 0.70% Cu and 0.015% Mo. (El Abra is almost entirely government- controlled; but both Los Pelambres and Andacollo are mostly under private ownership.)

Jan 11, 1974

By Sen A. K

The Chiria Iron Ore deposit falls within the well-known Horse-shoe-shaped Singhbhum-Bonai-Keonjhar belt in India, where most of the deposits supplying ore to various steel works of Steel Authority of India Limited (SAIL) and Tata Iron and Steel Company (TISCO) are located. With an estimated reserve of about 2000 million tonnes of ore (at 55 per cent Fe cut-off) spread over four contiguous blocks, it is the largest iron ore deposit in India and one of the largest in world. The present study is confined to only one of the four blocks of Chiria viz North Block, comprising an area of 2.11 km2. `Corporate Plan 2005' of SAIL envisages development of a large open cast mine at Chiria to meet its enhanced requirement of iron ore by 2001-02 AD.

Jan 1, 1995

By John G. Kovac

A computer simulation has been developed by the US. Bureau of Mines to estimate the chances of a miner making a successful escape while wearing a self-contained self-rescuer (SCSR). The model takes into account (1) training in the use of SCSR's, (2) apparatus integrity, and (3) oxygen cost of a mine escape. This report examines survival odds for a prototypical escape, and illustrates how these odds change when SCSR training is improved.

Jan 1, 2009

By James A. Barr

THE writer's first experience with flotation was during World War I, in the beneficiation of Alabama graphite schist ores. One plant used a cone with a peripheral overflow; dried ore was distributed by a rotating disk onto the surface of the water. No reagents were added. The flake-graphite film floated along with some fine silica. Dewatering screens separated the flake. Naturally unit capacities were low but results were satisfactory. Minerals Separation mechanical flotation machines were used in another graphite mill. Pine oil was added directly to the head cells, with very good results. All the graphite concentrates from both types of flotation were carefully refined after drying by passing through burr mills, followed by very close sizing on sifters. In March 1927, the writer ran a very successful flotation test on minus 28-mesh, deslimed, Tennessee brown phosphate "sand,"[t] using a mechanical laboratory machine built in the shops of the Anaconda Copper Mining Co., through the courtesy of Ernest Klepetko. The machine was soon converted to a subaeration type, with improved results. This phosphate research program was greatly enlarged and led to the formation of the Phosphate Recovery Corporation. The development of nonmetallic flotation followed rapidly. The first flotation machine for beneficiation of phosphate was installed in January 1928, in a pilot mill, by International Minerals and Chemical Corporation, at Mulberry, Florida. These machines were Minerals Separation, 24-in., subaeration types, with weir control of pulp between cells. The sand bleeders were very small-about 1 ¼ -in. diameter. As the feed contained 15 to 25 per cent plus 28-mesh material, the cells choked up frequently. This was corrected by cutting a 2 by 6-in. bleeder opening above the impellers, at grid level, which short-circuited the coarse fractions directly into the feed of the next cell. The matter of size classification and grinding was a considerable problem, which does not come within the scope of this article. Because of the troubles noted above, cascade-type roughers were installed in the second flotation plant, built about 1930. Experimental cells had been tried in 1928. General plant layout is shown in Fig. I and details of the cascade construction in Fig. 2. The cascade installation in plant No. 2 gave good results and eliminated troubles due to choke-ups and coarse feed. The capacities and metallurgical results equaled those of the modified 24-in. Minerals Separation flotation machines in plant No. I The objections to the cascade installation are the floor space and mill height required. In 1939 an improved Minerals Separation machine was tested in parallel with the cascades. Extensive tests indicated

Jan 1, 1945

Slovenliness is as reprehensible in words as in clothes. Much writing that we recognize as poor in style is merely sloppy. Just as some students postpone the necessary shave or forget to change their collars, so young engineers in writing drop their articles, definite and indefinite, or omit prepositions where they are required, possibly to compensate for those they use unnecessarily The work will begin [on] Saturday. Influenza seriously affected many mines [during] the last three months. Flotation in America [during] the last two years has made tremendous strides. Construction of the mill started [on] August 12, 1915, at which time 75% of the excavation was completed. The idea I wish to convey is [that] there are mineral deposits to which the present law applies badly. For this reason, if there was [for] no other, the ownership of the ore below and [of] the surface above should go together. When a unit of mapping is furnished, be the unit a claim or [a] group of claims, it is necessary . . . A fully stocked store was started in Park City and all employees [were] sold merchandise on a strictly cost basis. The word "merchandise" is left without government or agreement. 'I suggest: ". . . and merchandise was sold to all the employees on a strictly cash basis." The verb 'be' is serving concurrently both as a principal and as an auxiliary in the following: At first the work was interesting and [was] liked by most of the men. The sulphide ore was more complex or [was] milled at an increased cost. The failure to repeat the auxiliary verb in successive clauses is a common error, as in The filter is filled with liquid allowed to empty, and then ignited.

Jan 1, 1931

By Gonzalo Bernstein, David G. Meadows, German Naranjo, Edgardo Tapia

"During the last decade Antofagasta Minerals’ Los Pelambres Mine has dramatically increased its ore throughput following the fast initial phase ramp up through a series of planned incremental expansions. The original 85,000 mtpd, two SAG line plant was commissioned in 1999 and rapidly exceeded nameplate tonnage in only a few months. Following this, the inclusion of a pebble crushing circuit resulted in throughputs in excess of 114,000 mtpd and a recent, final third line SAG and ball mill addition have taken the plant to over 175,000 mtpd even with increasing ore hardness and changing ore feed characteristics. The progressive changes are described in this paper together with how the technical challenges have been met.INTRODUCTIONMinera Los Pelambres is a world class copper-molybdenum operation located in the Salamanca area in Chile, in region four, approximately 500 km north east of Santiago, the capital of Chile. In the late 1990s Antofagasta Minerals developed the Minera Los Pelambres project in Chile at an investment cost of approximately $1.3 billion USDs. The project construction was successfully led and completed by Bechtel Corporation in 1999 and within a matter of months the plant was already exceeding the nameplate capacity of 85,000 mtpd. In 2001 a pebble crushing circuit was added to raise the capacity to 114,000 mtpd. In the early part of 2003-2004, it was recognized that the hardness profile was changing with depth and that in order to maintain the plant capacity additional power would be needed in the SAG mills together with upgrading of the primary crusher. In conjunction with these changes a fifth ball mill and a second primary crusher station would also need to be installed. A further detailed engineering study and evaluation was initiated by Minera Los Pelambres. This was lead by Bechtel Corporation with major design contributions from FLSmidth and Siemens in order to establish the re-powering requirements for the SAG mills. These re-powering changes together with the inclusion of a pebble crushing circuit took the plant to up to 125,000 mtpd even with harder more competent ores. Finally in the last two years an additional grinding line has been added to take the capacity to consistently over 175,000 mtpd. The third line was installed in a record time of 256 days. A schematic of the current comminution circuit, discussed in this paper, is shown in Figure 2."

Jan 1, 2012

By A. B. Szwilski

The mineability and coal processing costs are influenced largely by the structural and physical properties of the coal seam. The mining process involves coal cutting, pillar support, crushing, and floating. A correlation between the rank, ash content, and coal strength/stiffness is discussed. The coefficient of variability of rebound tests on the face of various coal seams are compared with those of laboratory compressive strength tests by other investigators.

Jan 1, 1988

By Vladimir S. Zharov, Vyacheslav A. Tsukerman

"Conceptual imitative dynamic model of developing enterprises for medium and long-term period permitting to ensure coordination of interests of the enterprise and territorial environmental authorities has been developed to enable the process of the prognostication and management of a concentrating mill development, in which a symbol language and terminology familiar to the manager of the company are applied. An algorithm of practical application of this model of company development was elaborated as well as a general methodological approach to the prognostication of the development and procedures of its implementation. The general methodological approach to the implementation of the model has been defined. Within the framework of system approach, a concentrating mill is considered as a subsystem of an ore mining and processing company or a mining and smelting one. A concentrating technology is considered in dynamics, its change is determined by the task of making the company operation profitable. Technological indicators are secondary relative to financial and economical indexes. At the same time, technological and economical indexes are determined in their interrelation with ecological parameters. The elaborated model allows us to estimate all necessary economic, financial and technological indexes in their interrelation both for the company as a whole and as separately redistributed estimating the basic prognostication documents - accounting balance-sheet, profit and loss report, as well as the funds flow statement. When varying the managing parameters, all necessary result-producing financial and economical indexes are estimated and a need in and a possibility of an external funding by various sources are considered.The implementation of the model enables one to determine the required scale of production capacity, as well as the amount of raw-material resources needed. In case of shortages of the latter, there should be considered various scenarios of the production capacity enhancement or the possibility of commissioning of new sites or deposits and introduction of improved technologies."

Jan 1, 2003

CONTENTS PAGE THOENEN, J. R.-Limestone Production as a Mining Problem. Discussed by Oliver Bowles, J. T. Singewald, S. R. Russell 1 GRIGGS, C. C.-Engineering in Limestone Production. Discussed by W. C. Phalen, John Rice, Samuel M. Shallcross, Oliver Bowles, Nathan C. Rockwood, George Milliron 2 WILDER, FRANK A.-Rotary Calciners for Gypsum. Discussed by L. K. Arm-strong 9 PORTER, JOHN J.-Manufacturing Problems of Cement Industry. Discussed by Samuel M. Shallcross 9 KIRKHAM, VIRGIL R. D.-Phosphate Deposits of Idaho and Their Relation to the World Supply. Discussed by F. A. Wilder, S. L. Willis, G. R. Mansfield, R. W. Stone, L. K. Armstrong 9 Limestone Production as a Mining Problem Discussion of the paper of J. R. THOENEN, presented at the New York Meeting, February, 1925, and issued, as Paper 1417-H, with MINING AND METALLURGY, February, 1925. OLIVER BOWLES, New Brunswick, N. J.-I am so thoroughly convinced of the growing importance of underground work in the production of limestone that I had the author make a detailed study of limestone mining for the Bureau of Mines and prepare a report on the principles of limestone mining. Many limestone operators, long accustomed to open¬pit work, are being forced to mining. About 6 months ago I thought there were twenty-five or thirty underground limestone operations in the United States but the author has been finding new ones until his list now runs nearer sixty. Some of these are very extensive; one at least has 4 ½ miles of underground workings. There is an ever-expanding field for the engineer in the operation of limestone mines and quarries. Some of the larger companies realize the need of skilled engineering advice, but many of the companies regard the engineer as an unnecessary expense. Although almost every metal mine, even those handling only a few hundred tons of ore per month, employs a mining engineer, many limestone operations ten times as large employ no mining engineers. Few mining engineers are at all familiar

Jan 6, 1925

Executive Committee. GEORGE F. KUNZ, Chairman. E. GIBBON SPILSBURY, Vice-Chairman. THOMAS ROBINS, H. J. SEAMAN. Louis D. HUNTOON, Secretary-Treasurer. Meeting, Apr. 4, 1913. A joint meeting of the New York Section of the American Institute of Mining Engineers, the American Society of Mechanical Engineers, and the American Institute of Electrical Engineers was held in the large auditorium of the Engineering Societies Building, 29 West 39th Street, on Friday evening, Apr. 4, 1913, and an exhibition of the Edison Talking Moving Pictures was presented before the Societies, together with exhibitions of the work which is being done by the Edison Co. in making moving pictures to illustrate lectures on natural science and the useful arts for school and college work. Introductory remarks were made by Mr. J. W. Lieb, Jr., and followed by an exhibition of moving pictures illustrating the formation of crystals, the operation of different types of pumps, magnetic forces, electro-magnetic separation of iron ore, the evolution of the fly, and many other most interesting studies. One of the films, entitled The Formation of Crystals, showed a moving picture of a boy, whose laboratory was the kitchen, dissolving salt in a test tube filled with hot water. The boy then poured the solution of hot salt into a watch glass and placed it under the microscope to watch the crystals form. This film was immediately followed by another showing what the boy saw through the microscope. The solution at first was free from crystals. Gradually the crystals commenced to form and increased very rapidly after once starting, shooting across the screen with lightning speed. The film illustrating the separation of iron ores by the Edison electro-magnet showed an ore bin with an electro-magnet set at one side and below the bin. As the ore was dropped from the bin the magnetite was drawn into the. electric field and deposited in a separate rile from the sand.

Jan 5, 1913

By M. D. G. Salamon

In view of an urgent need for a simple means of simulating the behaviour of stratified rock masses, a long-dormant linear model is revived, generalized, and discussed in some depth. The model is piecewise homogeneous, consisting of a pile of homogeneous isotropic laminae in which the interfaces between beds are parallel and free of shear stresses and cohesion. The continuity of stresses and normal displacements is assured across the bedding planes and, to maintain simplicity, the theory of thin plates is used as the kernel of the model. The paper covers the case where the rock mass consists of discrete beds in which the layers are arranged either heterogeneously or systematically. The stratification is regarded as uniform when all the layers are of the same thickness and their Young's modulus changes exponentially with depth; and as homogeneous when all the laminae have identical thickness and properties. The case of uniform stratification is also treated on the basis of an equivalent quasi-continuum derived from the basic model. Attention is focused on the derivation of influence functions. It is demonstrated that the quasi-continuous models, when they are available, can replace their distinct-layer counterparts. The homogeneous quasi-continuum, which permits the derivation of its influence functions in closed form, facilitates the determination of the roof and floor convergence. In the case of a significant class of problems, the convergence distribution is defined by a second-order differential equation in the xy plane, which simplifies to a Poisson's equation if the mining excavations are unsupported. With this result, the paper prepares for the solution of a host of practical problems. These solutions are presented in a series of papers that are in the course of publication.

Jan 1, 1991

By W. A. Boyer

Edward Thomas (U.S. Bureau of Mines, Washington, D. C.)—This excellent article on an ingenious and successful installation of wooden rock bolts loses much of its effectiveness through an attempt by the authors to establish the general adaptability of this type of support. Possibly because they have only local experience as a guide, they imply erroneously in the first paragraph that the Bureau of Mines has been opposed to wooden bolting, although later in the article reference is made to a Bureau publication on the subject. In 1947 the Bureau of Mines decided to sponsor experiments in roof bolting in coal mines because the experience of the St. Joseph Lead Co. had indicated that this type of roof support appeared to be a roof-fall accident-prevention measure that might be adopted and also effect economies in operating cost. Justification for this belief has been borne out, particularly in coal mining. This program has been carried out under the following general program: 1—The Roof Control Section of the Bureau of Mines has advocated and initiated underground experiments under controlled conditions with many different ideas related to rock bolting since 1947. In no instance has cooperation in developing an idea been refused, no matter how ridiculous it may have seemed at first glance, if it has been requested by a mining company. 2—The Bureau of Mines has no police powers over the selection of roof-support devices and seeks none. 3—At the request of an operator, the Bureau of Mines will make comparative tests on various types of bolts underground and will submit resultant data for the operator's consideration. 4—Wherever possible, the Bureau publicizes successful installations, so that others may benefit from this experience; however, it is careful not to discriminate between manufacturers of bolts or bolt-installation equipment. Unsuccessful experiments probably should also be publicized, but from a practical standpoint it is usually not feasible. In other words, the role of the Roof Control Section of the Bureau is in line with the original purpose for which the Bureau was first organized: to serve industry through gathering, analyzing, and disseminating factual data. It would seem to be logical that the starting point for any experimentation on roof bolts in coal mines should be the time-proved practice of the

Jan 1, 1955

By A. Scheltema Beduin, M. Kalisch, E. Floch, R. J. Dijkhuis, H. J. Oterdoom

In metallurgical copper production, the traditional aim is to increase recovery of copper to the maximum. SMS Siemag (SMS) has supplied numerous furnaces for this application. New targets are to make sure end of line products are as safe as possible with respect to health and environment, and to maximize raw material utilization. This means a for example a minimization of leachable metals in slag, so it can be safely used as a construction material, and either a targeted concentration or fixation of volatile compounds, such as arsenic. Currently, 2 process routes are generally applied for slag cleaning. The first is grinding followed by flotation, and the second is slag cleaning in an (electrical) furnace. Popularity of both options has fluctuated over the years, and currently the milling-flotation seems to be the more popular option. In this article some of the advantages and disadvantages of both methods are described, and especially how long term environmental policies could have an impact on the decision which process route to choose. Finally, this article will describe some of the developments SMS is working on in pyrometallurgical slag cleaning that could influence the direction for the design of the copper plant of the future.

Jan 1, 2014

By E. H. Bronson

PROPERTY of Malartic Gold Fields Ltd. is situaated in the great clay belt in the northern part of the Province of Quebec. This belt represents the floor of the glacial lake Barlow-Ojibway. The clay blanket has a gently rolling, almost flat surface, with here and there projecting knobs and ridges that outline the large irregularities of the surface on which the clay was deposited. At irregular intervals glacial eskers dominate the landscape. The ore-bearing country rock is covered by strata of clay, sand, and silt to a depth varying to 40 ft. There are serious structural problems when it is necessary to place loads of unequal intensities on this surface to support buildings and machinery for a modern mining plant. Earlier mining companies and their engineers paid little attention to the science of soil mechanics, partly because they believed it unnecessary and partly because they knew little of the subject. The results are evident in some of the tottering structures in older camps. Careful analysis of soil problems is well worth-while, since cost of foundations may vary from 20 to 50 pct of the final cost of a structure. Low operating and maintenance costs can be achieved only in this way.

Jan 11, 1957

By R. P. Carreker, J. C. Fisher

Cheep tests are normally constant load tests. Such tests approximate some types of service conditions and therefore are justified from the engineering point of view. Coupled with this consideration is the advantage of simplicity inherent in constant load tests, as contrasted with the comparatively complex requirements of a constant stress test. It is not surprising that the vast majority of creep tests reported are of the constant load type. Despite the enormous amount of accumulated creep test data, plastic flow is by no means completely understood. The widespread use of constant load tests is at least partly responsible for this lack of understanding. Any attempt to analyze deformation must involve the more fundamental quantity stress, rather than load. It is possible to predict constant load behavior from known constant stress data, but the reverse is much more difficult. When a metal specimen elongates, as in a creep test, the cross section decreases, maintaining constant volume. Thus For a constant stress test the force on the specimen must be decreased as the cross section decreases, that is, this force must be inversely proportional to the elongation of the specimen. An-drade has described three methods of obtaining the constant stress condition,l-3 each of which is relatively complex. The most recent proposal,³ suggests a major simplification which maintains the simplicity of the constant load test while approximating quite closely the desirable condition of constant stress. Andrade's device is admittedly more accurate but the method described below has definite advantages Consider a specimen in the form of a "V" supported at its ends. If a weight be applied at the vertex of the angle, the stress in each leg of the "V" If this stress causes an elongation ?1 in each leg of the "V," the angle decreases from a. to a smaller angle a1. The quantity sec — thus decreases with specimen elongation while the quantity 1/A increases. By selecting proper initial conditions it should be possible to hold S/So very nearly constant at unity. The proper initial conditions are realized when a0 is made equal to approximately 90°. Fig 1 compares the ratios of S/S0 for a0 = 85, 90, 95, 100°, with a0 = 0, that is, a straight speci- men, for true strains up to e = 0.10. It may prove convenient to measure X, the movement of the vertex, rather than the true elongation 1. Contour lines of X/lo are also plotted in Fig 1. The method for obtaining constant stress described above is especially suited to the testing of small wires, but may easily be extended to rods of any diameter through the use of a suitable grip which serves as the vertex joining two identical rods forming the legs of the "V." References 1. E. N. da C. Andrade: On the Viscous Flow in Metals, and Allied Phenomena. Proc. Roy. Soc., A, 84, 1, (1910-11). 2. E. N. da C. Andrade and B. Chalmers: The Resistivity of Polycrystalline Wires in Relation to Plastic Deformation, and the Mechanism of Plastic Flow. Proc. Roy. Soc., A, 138, 348, (1932). 3. E. N. da C. Andrade: A New Device for Maintaining Constant Stress in a Rod Undergoing Plastic Extension. Proc. Phys. Soc., 60, (3). 304, (March, 1948).

Jan 1, 1950

By John V. Beall

The Glidden Co., a newcomer to the mining industry, will be putting on stream its Lakehurst mine and concentrator this spring. Ilmenite-bearing placer sands will be mined and concentrated in a spanking new combination gravity, magnetic and high-tension separation plant. Glidden, well known as a paint, chemical and food manufacturer, consumes titanium dioxide as pigment in its paint business. The commodity is produced at the company's Adrian D. Joyce Works in Baltimore from ilmenite purchased in India and Australia, The Lakehurst operation, handily located in Ocean County, N. J., will dampen any deficiencies in quantity or price which might occur from foreign suppliers. This objective is no overnight concoction of The Glidden Co., because the move at Lakehurst was preceded by an attempt to start up in Florida. That project was abandoned when it was found that the titanium dioxide values were largely in rutile-a mineral which does not lend itself readily to the digestion process of the Baltimore chemical plant.

Jan 1, 1962

By Edmundo Alfaro

"The paper point out about on the use of ion exchange resins for adsorption of gold from ammoniacal thiosulfate solutions. In this sense, the gold can be recovered from ammonium thiosulfate solutions with strong base resins. The amount of gold loaded onto the resin in a batch process is a function of gold concentration in solution, amount of resin, volume of solution, copper and competing ions concentration in solution. Thiosulfate concentration in leaching solution has influence on gold loadings onto resins; in contrast, ammonia concentration in solutions has no influence on gold loadings. Gold seems to be loaded onto the resin preferentially over copper - thiosulfatecomplexes and also over thiosulfate ions. Polythionate ions strongly compete with gold and copper thiosulfate complexes for resin sites. This causes reduction on gold and copper recoveries from the leaching solutions. Even more, polythionates are produced in leaching solutions when thiosulfate is oxidized by the action of both copper and oxygen. "

Jul 31, 2003