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By Ali Dehghani Ahmadabadi

Gravity separation technique is widely used in mineral beneficiation practices for its low cost, ease of operation, and eco-friendly nature. The most commonly used gravity methods for beneficiation of iron ores are shaking table, jig and spiral methods which aren't very effective for iron mineral fines. Multi-Gravity Separator (MGS) is suitable for the treatment of fines with a maximum particle size of approximately 500 µm. This study was performed on a low-grade haematite iron ore from Chadormalutailing dams. Detailed mineralogical, physical and chemical characteristics of a goethiticlateritic iron ore showed that the sample contained porous and friable oxides and hydroxides of iron. The ore sample had a feed grade of 35% Fe, 1.1% FeO, 15.5% SiO2 and 8.5% Al2O3. Haematite and goethite are the main iron-bearing minerals while quartzite and kaolinite are the major gangue mineral constituents. In this paper, the statistical evaluation and optimization of grade and recovery using a factorial design of experiment (DOE) method has been carried out for Chadormalulow grade ultra-fine haematite tailings with MGS. The input process parameters considered are drum speed, tilt angle, wash water flow rate and pulp density. The results show considerable improvements in both the quality characteristics such as grade and recovery with statistical evaluation and optimization, compared to the initial value of grade and recovery. Keywords: multi-gravity separator, mgs, statistical evaluation, optimization, haematite

Sep 1, 2012

By DJ McKEE

Process control emerged in the mid-1960s as a new and exciting method of improving the performance of mineral processing operations. The early Australian developments, principally in Broken Hill and Mount Isa, were based on pioneering work in instrumentation, the availability of small digital computers and a particularly effective partnership between companies with technological foresight and University and CSIRO research groups. Initial progress was rapid and within ten years many plants were committed to process control. Process monitoring is now routine and most circuits have some level of control. However, few plants have comprehensive optimising control systems as the difficulty of developing control strategies which can cope with the wide variety of conditions encountered in most mineral plants has been fully appreciated. This paper summarises past experience and assesses the degree of application of different forms of process control in metallurgical plants. Barriers to the effective utilisation of opt rising control are identified and some suggestions for advancing the application of control are made.

Jan 1, 1992

By O. B. Horne, R. O. Morgan, C. E. Anderson

"Air-photo interpretation and photogrammetry are two of the most effective and versatile tools available to the petroleum industry. The techniques have proven successful in providing solutions to many of the problems encountered in the design and construction of oilfield projects.Although most technical personnel are aware that air-photo interpretation and photogrammetry are useful in the selection of routes for roads and pipelines, few realize the true scope of the techniques or the wide variety of areas in which they are applicable.This paper briefly describes the principles involved, and reviews a number of typical applications of particular interest to petroleum companies. Excessive detail is avoided, rather the emphasis is placed upon the wide spectrum of possible applications. It is stressed that on-the-ground examination generally is a necessary adjunct, and that there are certain limitations to the techniques discussed.Properly applied, however, air-photo interpretation and photogrammetry can offer significant advantages in terms of time, flexibility, secrecy and economy."

Jan 1, 1968

By John Furness Park

This paper, which describes the mining methods and practices at the Jarbidge mines of the Elkoro Mines Co., is one of a series of papers being issued by the United States Bureau of Mines on mining methods and costs in various districts throughout the United States. LOCATION AND HISTORY The Elkoro Mines Co.'s property is located at Jarbidge in the northeast corner of the State of Nevada (fig. 1). The camp is 9 miles south of the Idaho line; the nearest railroad point is 70 miles to the northeast at Rogerson, Idaho. A road leading to the south and connecting with Deeth, Nev., is passable during the summer months; the heavy snowfall which generally takes place early in the winter usually closes the road until the first of July.

Jan 1, 1931

By A. J. Antony Chettupuzha

Electronic Product and Process Management [EPPM] systems provide the capability to establish and map information flow between different parties in a construction project as well as model project processes. Much of the information relating to processes and their structure, the actors that operate them, and the data associated with each instance of a process is encapsulated within workflows. The wealth of information contained in an EPPM system can be exploited to extract knowledge that can provide significant cost benefits to construction companies. Workflows provide an ideal medium for the capture of knowledge over the course of a project lifecycle. We demonstrate how this knowledge may then be used to analyze workflows and determine metrics that establish the suitability of workflows to construction processes. We present a conceptual approach to measure the performance of a workflow, its constituent components and evolution, which may be used to lay the foundation for establishing paragon workflows suited to classes of construction activities.

Aug 1, 2013

By Philip L. LeHoux

"Kennecott Barneys Canyon Mining Co. is a gold heap leaching facility that has been in operation since 1989. In 1994, a flotation plant was commissioned to remove sulphide minerals from refractory sulphide ore. Tailings from the plant are mixed with oxide heap leach material in order to produce a geotechnically stable agglomerate from which the gold is leached and recovered in a conventional heap leach cyanidation process. The experience to arrive at an effective blending methodology is discussed.IntroductionAgglomeration is the practice of binding fine particles to coarser rock or other fines in order to avoid the deleterious effects of mobilizing the fines during the course of heap leaching(l-Chamberlin). Agglomeration has been considered a key component of successful operation at many heap leach sites. If the ore is of sedimentary origin and crushed, there is a high likelihood that the resulting product will contain a significant quantity of fines and a skewed gradation, that i~, a disproportionate amount of coarse and fine particles, with few in the intermediate size range. The exact methodology for determining whether the practice of agglomeration will have to be integrated into the operating scheme has been well discussed. These conditions are primarily geotechnical and geochemical. This paper will deal with the specific experiences of Kennecott Barneys Canyon Mining Company in modifying the agglomeration practices to suit evolving operational requirements."

Jan 1, 1997

"Status of the Mineral Industries" provides a written and graphic view of the Nation's mineral position and its mineral industries. The report, issued annually by the Bureau of Mines, U.S. Department of the Interior, describes recent activities in mineral production, consumption, imports, exports, and uses of significant minerals and mineral raw materials. Charts profile trends for the past 28 years in supplies and uses of iron, steel, major nonferrous metals, primary nonmetallic construction raw materials, fertilizers, and plastics. Also included are current and historical financial data on the mineral industries, such as debt-equity ratios, asset-to-liability ratios, and plant and equipment expenditures.

Jan 1, 1979

By Arcy, D&apos Banister

The productive potential of the Nation's principal active and inactive silver mining districts has been evaluated, using 1964 economic conditions and assumed silver prices ranging up to $3 per ounce. On this basis, the United States has an estimated 5 billion ounces of unmined silver, excluding minor byproduct silver in gold deposits. Approximately 3.5 billion ounces are contained in deposits requiring higher silver prices to be economically minable, and about 1.3 billion ounces are in currently operating mines. An analysis of silver consumption trends since 1954 indicates that the free world industrial market will climb to nearly 800 million ounces annually by 1985. U.S. industrial silver consumption has been projected to increase at an annual rate of 4 percent from 1965 to 1985. Average annual increase for the remainder of the free world has been 8.1 percent since 1953; this is expected to level off with an estimated average increase of 5 percent to 1975 and 4 percent from 1976 to 1985. Foreign silver production has, in the past, exceeded consumption, but in 1960 the supply deficit was over 100 million ounces. U.S. production, also traditionally exceeding demand, was suddenly overtaken at the start of World War II. By 1964 the annual deficit, excluding coinage, was over 84 million ounces. World coinage requirements of silver are fast declining and expected to total only 25 million ounces annually by 1985. In fact, coins are already becoming major short-term source of silver to fill the large deficit between industrial demand and current production. The larger, long-term deficit (to 1985, the limit of this study) must be balanced by silver from the hoards and new production from silver deposits. Eventually all of the deficit must be met by new production or silver prices will rise until consumption is greatly curtailed. To balance free world supply and demand, it is estimated that the free world must produce an additional 85 million ounces by 1975 and 375 million ounces by 1985. The estimated proportion expected from U.S. deposits is 17 million ounces by 1975 and 74 million ounces by 1985.

Jan 1, 1969

By W. A. Gow, G. M. Ritcey, M. C. Campbell

"Uranium is a unique commodity. It is both a metal and a fuel, It has both commercial and military uses. It yields ""clean energy "" but presents environmental concerns. All of these factors have an impact on the commerce of uranium.Being a metal, uranium is extracted from ore like many other metallic minerals. As a fuel, it is subject to the vagaries of energy commodity market forces. The history of uranium in the first nuclear weapons has led to nation al governments carefully controlling production and sale of uranium. The spectre of radioactive contamination of the environment adds further to the public concern over the disposal of low-level radioactive wastes from uranium processing and use.There have been a number of excellent reviews on the commercial aspects of the uranium industry. In this discussion, these aspects will be briefly summarized to provide a general picture of the strengths of the Canadian uranium industry and the pressures to which it is being subjected currently. The principal thrust of this paper will be to outline Canada's resource strength and to identify some factors which will affect Canada's ability to continue holding a sizeable share of the world uranium market."

Jan 1, 1985

By G. E. Veins

This paper summarizes an investigation in which beneficiated ilmenite ore was smelted in a continuous, three-phase, 250 kv.a., open-top electric furnace. Minus %. inch ore was smelted, using the standard method. Fine ore, in the order of minus 14 mesh, was smelted in the briquetted form by the open bath method, and in the unagglomerated form by the cold dry-top method. The latter was shown to be superior. The data obtained .are discussed at some length. During the investigation, slag aver-aging 82.5 per cent Ti02 was produced over a period of 87 hours, the maximum being 85 per cent. Such slag should .be particularly attractive for the production of titanium tetrachloride, from which titaniurn metal is produced. The advantages of using paper-mill bark for producing a furnace charge of low bulk density, as required in cold dry-top smelting, were emphasized.

Jan 1, 1957

By W. C. Morgan

Recently passed federal strip mining legislation officially emphasizes that the increased coal production required by this country through surface mining is going to be obtained only with stricter environmental standards. Dozing overburden down the hillside in Appalachian contour mining or leaving drag1ine spoils in area mining is now taboo and it is now or will soon be necessary to return the disturbed land to as good or better condition than before mining. These new restrictions will create a need for new and better ways to do the job. This paper describes one approach for utilizing scrapers and dozers to strip all of the overburden and to replace that overburden in an environmentally satisfactory fashion. The objective was to do this at a lower cost than that possible with the traditional dragline system using dozers and scrapers for reclamation and topsoil handling. In area stripping, the dragline has been able to move overburden at an extremely low cost. Operating costs of 8-13¢/bcy are typical in many operations where rehandling is not required. However, the cost of leveling the spoil piles and rehandling topsoil add considerably to the low basic cost of drag1ine stripping.

Jan 1, 1977

By William R. Jones, Robert M. Hernon

This report on the Central mining district of New Mexico is the partial culmination of an intensive U.S. Geological Survey effort dating back some 30 years. Robert M. Hernon went to Silver City in 1948 to finish a detailed restudy of the district that had been started in the thirties by Samuel G. Lasky. He was joined by William R. Jones in 1951, and Jones took over as project chief when Hernon resigned to do consulting work in 1953; it was under Jones' guidance that most of the work was brought to completion or nearly so ( 17, 22-24, 26-30). Hernon returned to the Survey in 1958 to work in .the southern Appalachians. Early in 1965 Jones urged that Hernon be reassigned to the Silver City project to help complete the Professional Paper report on the ore deposits of the Santa Rita quadrangle as well as to take over preparation of the report on the Central district for the Graton-Sales volume. This reassignment was approved, and Hernon began work on the present report. By late June he had completed most of it in draft form, and on June 28 Jones and Hernon left Denver for a short trip to Silver City to fill in a few gaps and to reacquaint Hernon with activities in the district, which he had not visited for 12 years. Late in the afternoon of June 29, 1965, as Bob and Bill were 85 miles short of their destination, their jeep collided head-on with a truck that was attempting to pass another vehicle in a cloud of dust. They both died instantly. As the most recent surviving member of the Silver City project (1958-1962), I was given the honorable though rather sorrowful task of putting the Hernon-Jones report "in shape" for publication. Fortunately the manuscript was already in good shape, so that the task has consisted of little more than minor reorganization and editing, and of preparation of the illustrations, abstract, and bibliography. The sections on wall-rock alteration had been left for Jones to complete in the light of his recently intensified interest in alteration geochemistry (25), and it is in these sections only that. the report may fall short, for they have been filled in from a 1958 manuscript by Jones on the ore deposits of the Santa Rita quadrangle that he intended to revise considerably. The shortcomings, however, are largely in the interpretation, not in the field data. As a brief but accurate summary of what was known about the geology of the Central mining district in 1965, this report stands as a fitting testimonial to the scientific dedication of two exceptional men.

Jan 1, 1968

By The Mine Staff

THE PROPERTY of the Lamaque Mining Company, Limited, ?is located in the Town of Bourlamaque, seventy miles east of Noranda, in Bourlamaque township, Abitrbi county, north western Quebec. Gold production commenced at Lamaque in April, 1935, with an initial mill capacity of 250 tons per day. The capacity was doubled in November of the same year, and in December, 1937, it further increased to 1,200 tons per day. During the war years the mill operated at a reduced tonnage, but in 1951 milling units were added along with complementary crushing and shop facilities to bring the capacity to 1,500 tons per day. Finally, in 1953, the capacity was raised to 2,000 tons per day, which rate is being maintained at the present time. The total production at Lamaque from April 2nd, 1935, to December 31st, 1956, has been 9,168,901 tons of ore from which 2,208,168 ounces of gold was recovered. The total value of this production , excluding E.G. M.À.*, was $77,869,653.

Jan 1, 1957

By R. W. Stahl

An emergency is defined as an unforeseen combination of circumstances that calls for immediate action. When applied to a coal mine, an emergency may call for prompt removal of the men to the surface through travelways other than the haulageway or intake airways, which are generally contaminated with irrespirable air as a result of an explosion or fire. Therefore, maintenance of adequate and travelable escapeways from all working areas of a mine is vitally important insurance against disaster. Several mine disasters could have been avoided if well-defined escape routes had been provided and made known to all mine employees. Such occurrences, unnecessary as they generally are, unfairly indict the industry when only a small segment thereof is involved. As a result of a rather recent disaster, which might not have happened if good escape routes had been provided, the Bureau of Mines decided to delve into the escape procedure to determine (1) what is being done in the industry and (2) what might be done at reasonable cost.

Jan 1, 1962

By J. L. Bowlby

The heats of combustion of fuels are determined in the laboratory by means of a calorimeter, usually of the oxygen bomb type. A known weight of the fuel is burned in an atmosphere of oxygen under approximately 400 pounds pressure in a heavy metal container-the bomb- and the heat evolved is imparted to a definite quantity of water. From the rise in temperature, measured by means of a Beckmann thermometer, and other data incidental to the determination, the heat value of the sample can be calculated. On paper, the method appears simple indeed, but in practice the determination of the heat of combustion is one of the most difficult of the various coal analyses. This h as led to considerable investigational work in order to obtain formula: whereby calorific values of solid fuels could be calculated from proximate analysis data al one. The proximate analysis of a fuel consists of the determination of moisture, ash, and volatile matter, with fixed carbon by difference. Sulphur determinations properly belong to the ultimate analysis, but in this section of the country, where the sulphur content of the coal is comparatively high, a request for the proximate analysis of a fuel implies the determination of the sulphur as well.

Jan 1, 1929

By Frank E. Dalton, Bart T. Lynam, Forrest C. Neil

The Tunnel and Reservoir Plan (TARP) is the largest tunneling program in the history of the metropolitan Chicago area (Figure 1). Between September 1976 and September 1977, rock tunnel contracts having an estimated cost of approximately $420 million will be advertised. During the past six months, the Metropolitan Sanitary District of Greater Chicago (MSDGC) has awarded contracts for 16.5 miles of rock tunnels in diam of from 9 ft to 30 ft having a total bid price of $120,261,750. RECENT CONTRACT AWARDS Addison-Wilmette Tunnel $63,140,480 Upper Des Plaines #20 Tunnel 35,749,664 Upper Des Plaines #21 Tunnel 21,371,607 Addison-Wilmette Tunnel The first contract was advertised in September 1975. This contract, described as the Addison-Wilmette Tunnel, runs from Wilmette Harbor at Lake Michigan under the North Shore Channel to Addison Street in the City of Chicago, a distance of 10 miles. The contract calls for constructing approximately 27,750 linear ft of 30 ft ID and 24,020 linear ft of 22 ft ID unlined rock tunnels, excavation of two construction shafts, and the excavation of 32 drop shafts of various diam. Two hundred ninety-three companies were notified of this contract being advertised, 70 companies took out contract specifications and 3 companies ultimately submitted bids. The contract was awarded to a joint venture of:

Jan 1, 1976

By T. A. Rickard

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 these they use unnecessarily The work will begin [on] Saturday. 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 tie 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 B. Singh

The use of wire ropes has already been tried in a few countries for roof support In mines. But the use of scrap wire ropes, as a method of support on extensive scale has not been reported from anywhere except India. Extensive trials using freshly discarded wire ropes for roof support were undertaken both in the laboratory and field. In laboratory, model beams supported with different reinforcing techniques were tested to evaluate their comparative load bearing capacity vis-a-vis reinforcing factor. Among all the tests, the model supported with wire rope system at 60° angle in combination with two supplementary vertical bolts offered the best result 1.e. about 95% reinforcement. It also accepted post fracture loading of the beam. In statical analysis too, the best result could be obtained with the rope installed across the gallery at 60° angle. All these findings are in conformity with the field observations obtained during roof stitching practices in coal mines. Of late, roof stitching, an effective and economical method of roof support developed at CMRS, India in 1972, found wide application in over 200 coal mines. In this method, a freshly discarded wire rope is grouted across a gallery in two inclined drill holes supplemented with two middle vertical roof bolts at every 1.0 to 1.2 m interval along the gallery. It is tensioned against the roof using wooden sleepers and thus, the whole system functions like a roof truss.

Jan 1, 1990

By Todd Hollingsworth

The Boddington gold mine is located near Perth in Western Australia in the Saddleback Greenstone Belt, a fault-bounded sliver of Archaean volcanic and shallow level intrusive rocks, surrounded by granitic and gneissic rocks. The mine began operations in 1987, producing about 7.7 t/a (250,000 oz/year) until mining ceased in 2001. Built on the footprint of the original mine, the Boddington gold mine expansion project involved opencut mining from two large pits. Expected gold production is around 31 t/a (1 million oz/year) for the first five years. It will be the largest gold mine in Australia. The mine has proven and probable reserves of more than 622 kt (20 million oz) of gold and has an expected life of more than 24 years. The mine is currently solely owned by Newmont Gold Corp., the world?s second-largest gold mining company, employing around 28,000 people worldwide. The conveyor and belt feeder contract for the Boddington gold mine expansion project was awarded by Aker Kvaerner Clough Murray Roberts (AKCMR) to FLSmidth Conveyor Engineering Inc. in August 2006. The contract involved the design and manufacture of 15 conveyors and 17 belt feeders with belt widths ranging from 450 mm to 2.4 m (18 in. to 96 in.) and conveyor lengths from 16 m to 2,172 m (52 ft to 7,125 ft). The total motor power added up to more than 16,700 kW (22,400 hp). The total length of all belting was almost 11.5 km (7.1 miles), and the total fabricated steel weight was approximately 3.7 kt (4,100 st).

Jan 1, 2010

By H. C. Rickaby

Introduction The township of Swayze, from which the Swayze gold area derives its name, is in the Sudbury mining division, approximately 150 miles northwest of Sudbury. The gold area may be regarded as situated at the southwest corner of a triangular area whose northeast and southeast corners are at Porcupine and Shiningtree, respectively, and whose sides are between 70 miles and 90 miles in length. On a geological map, it would be found that belts of Keewatin greenstones and sediments form the sides of this triangle, and that they surround a large granite mass. Prior to the summer of 1931 the Swayze corner of this triangle had probably been less prospected than the other parts and comparatively little was known of it from the standpoint of gold mining possibilities. The extensive belts of iron formation to the south and west of Swayze received some attention about the year 1909, and during the years 1927 and 1928 some prospecting was done in the townships of Greenlaw and Cunningham, south of Swayze, but chiefly for base-metals- copper, zinc, and lead. In the summer of 1931 a very promising discovery of gold-bearing quartz was made by J. G. and J. L. Kenty, working for the Brett-Trethewey Mines, Ltd., in association with Northern Canada Mining Corporation, and Northland Prospectors, Ltd., and this property, now known as the Kenty Gold Mines, Ltd., has been actively developed with very encouraging results. Following this discovery a6d during the summer of 1932 much prospecting took place in the area, as a result of which a number of other discoveries of gold were made, chiefly to the west of the original find. They are distributed over a wide area, which includes the townships of Rollo, Raney, Swayze, Denyes, Halcrow, and Greenlaw.

Jan 1, 1933