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By G. H. Lind

The Minerals Tertiary Education Council (MTEC), over the past decade, has worked closely with Australian higher education partners in metallurgical education to build capacity in this discipline to deliver high quality graduates for the Australian minerals-industry. This paper explores the benefits of industry engagement through a national innovative collaboration, the Metallurgical Education Partnership (MEP), and specifically the final year Process Design Project (PDP), over the four year period from 2008-2011. Some of the benefits discussed in this paper include outcomes of the student experience during an industry-intensive workshop, collaboration between higher education providers and aligning graduate attributes to meet industry requirements.

Sep 1, 2012

By Robert C. Maxton

The foundry industry is a basic source of structural component for all industry. Millions of tons of castings are produced annually in both ferrous and nonferrous alloys. These castings are subjected to a wide variety of heat treatments, finishing techniques, mechanical tests and machining operations. Through all of these steps the quality of the casting is of paramount importance to the end use of the product. The Quality Assurance Program at Minneapolis Electric Steel Castings Company is designed and established to provide a superior product for both original equipment manufacturers and the mining industry.

Jan 1, 1982

By Norman Paley, Finn Ouchterlony

Detailed fragmentation data for different blast delay timing tests at the Red Dog mine in Alaska are analyzed. This work is a continuation of previous work in which the crusher output was found to be better described by the three-parameter Swebrec function than by the Rosin-Rammler function. For a crusher model, the x50 variable sufficed to describe changing crusher input while b and xmax could be considered fixed. For the crusher output from aggregated stockpile rock, as measured by digital image analysis using Split-Online, the constancy of b was not as apparent. In this paper detailed stockpile data, single Split data series, and sieved belt cuts of crusher product are analyzed using the Swebrec and truncated Rosin-Rammler functions. The variability of b is confirmed. By using specific fraction passing sizes a shortcut is presented that removes the need to do curve fitting to determine the three Swebrec function parameters.

Jan 1, 2013

By Donald I. Bleiwas

The U.S. Bureau of Mines has evaluated the potential availability of nickel from 36 deposits or districts in 16 market-economy countries (MECs), analyzing more than 95 percent of production in those countries. This study indicates the quantity of nickel available on the basis of net production costs and total costs with a 0-pct and a 10-pct discounted cash flow rate of return (DCFROR). Costs of production are expressed in dollars per pound of recovered nickel. The study also indicates sensitivities of the cost of production to energy, labor, and other factors. The studied deposits and properties contain approximately 33 Mmt of recoverable nickel. About 26 Mmt of nickel is potentially recoverable from laterite deposits, of which 4.5 Mmt can be produced at $2.50/lb or less with a 0-pct DCFROR. Approximately 7 Mmt of nickel is potentially recoverable from sulfide deposits, of which about 6.3 Mint could be produced at $2.50/lb or less at a 0-pct DCFROR. The price of nickel averaged above $6.00/lb in 1988. Sensitivity studies performed for both laterite and sulfide deposits indicate that the total cost of producing nickel from laterites is most sensitive to increases in energy costs and that the total cost of producing nickel from sulfide deposits is most sensitive to increases in labor costs; sulfides are also affected by changes in revenues from byproducts.

Jan 1, 1991

By M. M. Gilkey

This report on water requirements for the New Mexico mineral industry includes data on industrial operations closely related to mineral production. It contains general information concerning public water supplies at five principal cities and a short discussion of water needs for agriculture. Background data are presented regarding the geography, hydrography, and water laws of New Mexico, as well as precipitatton and evaporation characteristics of the State. Most of the information on source, quantity, distribution, cost, and treatment of water was obtained in interviews with company representatives. Water systems at 46 operations are illustrated by schematic waterflow diagrams. The study revealed that the New Mexico mineral industry in 1962 used about 16 billion gallons of new water and reused 152 billion gallons, a total usage of 168 billion gallons. Consumption amounted to 7.6 billion gallons. Of the 16 billion gallons of new water, 11.9 billion gallons was "self- supplied" from ground water sources, and 2.6 billion gallons was self supplied from surface sources. Approximately 1.5 billion gallons was purchased. Some of the water from company-owned wells is piped as far as 30 miles. Reported costs of the self-supplied new water range from 1 to 20 cents per 1,000 gallons and average 8 cents per 1,000 gallons for power and maintenance. Inadequacy of the supply of new water at many operations necessitates large-scale recirculation. Reported costs for recirculating water (power and maintenance) average 1.8 cents per 1,000 gallons. For the entire New Mexico mineral industry in 1962, the value of product was $42 per 1,000 gallons of new water intake and $88 per 1,000 gallons consumed. Analyses of 40 water samples, listed in the appendix, show the wide range in water quality at plants throughout the State. Projection of the 1962 water requirements of the mineral industry indicate that the total demand for new water will increase from the 16 billion gallons used in 1962 to 24 billion gallons in 1980, a 50 percent increase; and to 36 billion gallons in 2000, which is 125 percent more than the 1962 intake of new water.

Jan 1, 1965

By M. M. Gilkey

This report on water requirements for the New Mexico mineral industry includes data on industrial operations closely related to mineral production. It contains general information concerning public water supplies at five principal cities and a short discussion of water needs for agriculture. Background data are presented regarding the geography, hydrography, and water laws of New Mexico, as well as precipitation and evaporation characteristics of the State. Most of the information on source, quantity, distribution, cost, and treatment of water was obtained in interviews with company representatives. Water systems at 46 operations are illustrated by schematic waterflow diagrams. The study revealed that the New Mexico mineral industry in 1962 used about 16 billion gallons of new water and reused 152 billion gallons, a total usage of 168 billion gallons. Consumption amounted to 7.6 billion gallons. Of the 16 billion gallons of new water, 11.9 billion gallons was "self- supplied" from ground water sources, and 2.6 billion gallons was self supplied from surface sources. Approximately 1.5 billion gallons was purchased. Some of the water from company-owned wells is piped as far as 30 miles. Reported costs of the self-supplied new water range from 1 to 20 cents per 1,000 gallons and average 8 cents per 1,000 gallons for power and maintenance. Inadequacy of the supply of new water at many operations necessitates large-scale recirculation. Reported costs for recirculating water (power and maintenance) average 1.8 cents per 1,000 gallons. For the entire New Mexico mineral industry in 1962, the value of product was $42 per 1,000 gallons of new water intake and $88 per 1,000 gallons consumed. Analyses of 40 water samples, listed in the appendix, show the wide range in water quality at plants throughout the State. Projection of the 1962 water requirements of the mineral industry indicate that the total demand for new water will increase from the 16 billion gallons used in 1962 to 24 billion gallons in 1980, a 50 percent increase; and to 36 billion gallons in 2000, which is 125 percent more than the 1962 intake of new water.

Jan 1, 1965

By S Porter

The Melbourne City Link Project is a privately funded road infrastructure project linking three significant existing freeways in the vicinity of the Central Business District. The State Government, through the Melbourne City Link Authority, has contracted Transurban to build, own and operate City Link for a concession period of 34 years before the road network is transferred to the State. Transurban has a contract with Transfield Obayashi Joint Venture (TOJV) to design and construct the works. The project is divided into the southern and western sections and the tunnel works comprised the significant component of the Southern Link. Outside of the cut and cover tunnels at the portals, the driven tunnels component was constructed by TOJV direct labour. TOJV subcontracted all design work to a joint venture of Hyder Consulting and CMPS&F (Hyder/CMP). The geology in the tunnel corridor and generally below the city of Melbourne is highly variable and constantly changing. The tunnels were driven, for the most part, in siltstone and sandstone of the Silurian age, but also intersected overlying basalts and clays. The Silurian bedrock is a fractured aquifer that is connected to overlying alluvial aquifers. Consequently, the construction of the tunnels was a complex engineering task. This paper details the operational relationships and procedures developed to deliver a design that was aligned to the construction constraints and delivered an end product that met all technical, quality, cost and program goals.

Jan 1, 1999

By S. J. Broderick

[The term "nonmetallic minerals? as commonly used is the mining industry, refers to those minerals of industrial importance that are mined essentially for uses other than for the metals contained. The field comprises several hundred rod minerals of industrial importance, of which 70 have can adequately described in the textbook Industrial Minerals and Rocks. A few o f the more important nonmetallic products are sand and gravel, salt, phosphates, clays, refractories, limestone, and cement materials. Some of the minerals, such as bauxite and pyrolusive, have both metallic and nonmetallic applications, but in this report only the nonmetallic mineral phases are considered. In the organic field of nonmetallics only coal is considered, as, the others - petroleum, natural gas, natural bitumens, and hydrocarbons - are of no importance in water softening.]

Jan 1, 1941

By M. I. Brittan

Cyanide leaching of two West African gold ores was studied in multiple laboratories to provide process-engineering data for plant design purposes. Unusually slow leach extraction kinetics were observed using routine cyanide leach test procedures with pregnant solution monitoring. Carbon-in-leach testing, however, showed normal rapid kinetic behavior, with the same ultimate gold extractions being reached in much shorter elapsed times. Kinetic curves based on washed solids assays also exhibited more typical leaching characteristics. The results bore all the hallmarks of some equilibrium inhibition of the leaching. It was surmised that ore gangue components were responsible for weakly adsorbing gold-cyanide complex reaction product, thereby holding up soluble gold in the solid phase. The term ?preg-borrowing? was coined to describe the reversible phenomenon and distinguish it from irreversible preg-robbing. The two ores investigated may represent an extreme form of a more general effect that in most instances might pass unnoticed. The effect can lead to misinterpretation of kinetic leach curve data and underestimation of calculated ore head grades.

Jan 1, 2008

By D. W. Breck

Zeolites were first recognized as a new group of minerals by Cronstedt with the discovery of stilbite in 1756. The word zeolite was coined from the two Greek words meaning "to boil" and "a stone" because of the loss of water when heated in the mineralogist's blowpipe (Breck, 1974). In 1845 it was discovered that certain soils lave the power of retaining ammonium salts Way, 1850). These were the first ion exchange experiments. Later it was discovered that it was the hydrated silicates in the soil that produced this phenomenon. Several years later a paper was published dealing with the action of dilute salt solutions on silicates which showed that this base-exchange principle, which we now call cation exchange, is reversible. The quantitative cation exchange behavior of zeolite minerals, such as chabazite, was studied. As a result any aluminosilicate which exhibited the property of ion exchange was referred to as a "zeolite," even today the term has been applied to clay minerals as well as synthetic organic ion exchange resins.

Jan 1, 1975

By F. E. Walker, S. J. Aresco, J. B. Janus

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal , expressed in British thermal units , and the composition as shown by proximate analyses . To these , when required , are added the ash- softening temperature , the free - swelling index , and the Hardgrove grindability index . Under most of these specification contracts the bidders guarantee the quality of the coal , and that guaranteed by the successful bidder becomes the standard of his contract . The deliveries are sampled in accordance with instructions 4/ issued by the Bureau of Mines ; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor and , if it is not , a price adjustment is made . Analyses of the delivered coal and tipple samples ( samples collected at mine tipples as coal is being loaded into railroad cars or trucks ) provide valuable data for use in evaluating future bids . In addition , the continuous sampling of coal as delivered is a check on the practical results obtained in burning the coal . The Government purchased approximately 5 million tons of coal in fiscal year 1962. In connection with these purchases , the Bureau analyzed 7,114 samples . These are published ( table 1 ) for the use of Government officials and the public . A series of publications has been completed on coal analyses by States or , where production is small in any one State , by groups of adjacent States . In addition to analytical data showing composition and quality of coals of the States , the publications contain brief descriptions

Jan 1, 1963

By Robert D. Pike

In November 1939, on behalf of the Harbison-Walker Refractories Co., the author undertook the study of the problem of utilizing the dolomite of northwestern Ohio for the manufacture of calcined magnesia suitable for use in refractories. Grateful acknowledgment is made of the unfailing assistance and encouragement throughout this work from the executive and technical staff of Harbison-Walker Refractories Company. The dolomite of the Niagara formation that is exposed or near the surface of a wide area in northwestern Ohio1 constitutes a vast supply of almost pure dolomite. It offers a virtually unlimited supply of cheap raw material of uniform dependable analysis for the manufacture of magnesia. A typical analysis of dolomite from the vicinity of Luckey, Ohio, follows: Stone Completely Calcined CaO(Sro)a............. 30.35 57.806 Mgo................... 21.55 41.050 SiO2. ................... 0.30 0.572 R2O3................... 0.30 0.572 Ignition loss............. 47.50 a SrO about 0.06 pct. Brines containing magnesium chloride or sea water can be reacted with calcined dolomite to produce magnesia.2'3 In such reactions the MgCl2 of the brine supplies some of the magnesia and the amount of dolomite required is thereby reduced by an equivalent amount, but brines of commercial importance containing magnesium chloride are some distance away from the purest grades of the dolomite of northwestern Ohio. It was decided therefore to concentrate upon the development of a suitable process for separating the lime and magnesia of dolomite, depending upon the dolomite itself as the sole source of magnesia. This would make it possible to place a plant at the dolomite quarry, thus eliminating the cost of transporting the stone and also rendering the calcined magnesia available at a most convenient production point, considering the cost of delivery throughout the steel industry. The selection of a process depending solely upon the dolomite as a source of magnesia also necessarily entails production of the lime content of the dolomite as a by-product. It was recognized that if such a lime by-product could be produced in a suitable form, a plant location in northwestern Ohio would also be advantageous for marketing the lime. The problem, therefore, was the discovery and development of a low-cost process for separating the magnesia and lime of the dolomite of northwestern Ohio and producing each in a form relatively free from the other, and meeting the respective requirements of established markets. A satisfactory solution of this problem has been found, and it is the

Jan 1, 1948

By Robert D. Pike

In November 1939, on behalf of the Harbison-Walker Refractories Co., the author undertook the study of the problem of utilizing the dolomite of northwestern Ohio for the manufacture of calcined magnesia suitable for use in refractories. Grateful acknowledgment is made of the unfailing assistance and encouragement throughout this work from the executive and technical staff of Harbison-Walker Refractories Company. The dolomite of the Niagara formation that is exposed or near the surface of a wide area in northwestern Ohio1 constitutes a vast supply of almost pure dolomite. It offers a virtually unlimited supply of cheap raw material of uniform dependable analysis for the manufacture of magnesia. A typical analysis of dolomite from the vicinity of Luckey, Ohio, follows: Stone Completely Calcined CaO(Sro)a............. 30.35 57.806 Mgo................... 21.55 41.050 SiO2. ................... 0.30 0.572 R2O3................... 0.30 0.572 Ignition loss............. 47.50 a SrO about 0.06 pct. Brines containing magnesium chloride or sea water can be reacted with calcined dolomite to produce magnesia.2'3 In such reactions the MgCl2 of the brine supplies some of the magnesia and the amount of dolomite required is thereby reduced by an equivalent amount, but brines of commercial importance containing magnesium chloride are some distance away from the purest grades of the dolomite of northwestern Ohio. It was decided therefore to concentrate upon the development of a suitable process for separating the lime and magnesia of dolomite, depending upon the dolomite itself as the sole source of magnesia. This would make it possible to place a plant at the dolomite quarry, thus eliminating the cost of transporting the stone and also rendering the calcined magnesia available at a most convenient production point, considering the cost of delivery throughout the steel industry. The selection of a process depending solely upon the dolomite as a source of magnesia also necessarily entails production of the lime content of the dolomite as a by-product. It was recognized that if such a lime by-product could be produced in a suitable form, a plant location in northwestern Ohio would also be advantageous for marketing the lime. The problem, therefore, was the discovery and development of a low-cost process for separating the magnesia and lime of the dolomite of northwestern Ohio and producing each in a form relatively free from the other, and meeting the respective requirements of established markets. A satisfactory solution of this problem has been found, and it is the

Jan 1, 1948

By Kurt Wiener

A major process control system is in some ways like a complex organism. The extremities, (that is, field instruments) are exposed to many hazards and suffer malfunctions of relatively minor and repetitive nature. Here I equate a stuck valve or dead transmitter with a skin abrasion or cut. The maintenance and repair of the extremities can be done by technicians with basic but thorough knowledge of relatively few problems and their solutions. Here I equate with administering Band-Aids and aspirin. On the other extreme, when the master control device (such as a computer) fails, one does not attempt home remedies. A "brain" specialist is called in. It is, however, crucial that the patient be able to clearly describe his symptoms. Getting down to the case at hand, a complex system consisting of field instruments, instrument racks, interface equipment, and perhaps a computer, may require maintenance at all levels. At the field equipment end where physical damage, corrosive atmospheres, reconfiguration, and routine calibration checks are common, the customer has the opportunity to develop a competent staff of maintenance people. The relatively high maintenance activity assures competence through repetition.

Jan 1, 1980

Conditional simulation provides a model of the ore body that represents variability in the data. This can be used to determine the impact of various grade control and mining strategies. A number of transfer functions are discussed that assist in optimizing grade control sampling. The cost effectiveness of various drilling and trenching techniques are discussed. Modelling of the expected performance of a mill head grade sampler is investigated. Conclusions are drawn about the likely impact of various sampling techniques on the economic performance of an operation and about applying sampling theory to grade control sampling.

Jan 1, 1999

By Walter K. Utt

The process of drilling and bolting the roof is currently one of the most dangerous jobs in underground mining, resulting in about 1,000 accidents with injuries each year in the United States. To increase the safety of underground miners, researchers froth the Spokane Research Laboratory of- the National Institute for Occupational Safety and Health are applying neural network technology to rite classification of mine roof strata in terms of relative strength. In this project, the feasibility of using a monitoring system on a roof drill to assess the integrity of a mine roof and warn a roof drill operator when a weak layer is encountered is being studied. Using measurements taken while a layer is being drilled, one can convert the data to suitably scaled features and classify the strength of the layer with a neural network. The feasibility of using a drill monitoring system to estimate the strength of successive layers of rock was demonstrated in the laboratory.

By Allen D. Look

Use of two-way radio communication at the Santa Rita open pit of the Kennecott Copper Corp. has furnished a satisfactory answer to the problem of communications for an operation covering an extended area. Coordination of operations has resulted, with little loss of time in making changes during the shift. Repairs are facilitated, and safety of operations is increased through better control of blasting and hazardous conditions. INTRODUCTION Expansion of mining operations brings increasing needs of improved communications to coordinate the mechanized operations that contribute to the efficiency of present-day open-pit methods. Equipment found satisfactory when first installed becomes inadequate as distances and demands increase. It is the, purpose of this paper to record the progress being made by one mine in meeting this problem.

Jan 1, 1952

By H. G. Stephenson, C. W. Gregory

"This article describes the methods used for pillar extraction in the Wilson Seam at Canmore Mines, Alberta. The Wilson Seam is extremely gassy and varies in thickness between 7 and 30 ft, with an average of 12 ft. The gradient varies from 5 to 30 degrees, with an average of 15 degrees. The seam was developed using Lee Norse miners to form pillars which the company intended to extract using the same machines. Before pillar extraction commenced, an abandoned and inaccessible mine 160 ft above the Wilson had to be drained of 360 million gallons of water. When this was done pillar extraction commenced. Conditions in the mine slowly deteriorated and after 6 months the decision to withdraw the continuous miners was taken. Slusher hoists were installed to replace the continuous miners, with the result that roof conditions and safety steadily improved."

Jan 1, 1972

By Stephen G. Downs

PCF?, or Penetrating Cone Fracture, is a propellant-based technique for rock excavation, which has significant potential for the mechanization of narrow-vein mining. The technique is currently being developed for use in the narrow-vein flat-dipping gold and platinum deposits in South Africa in conjunction with major mining companies. The technique is also applicable to steeply dipping vein deposits, such as those found in North America, Australia and elsewhere. The implementation of PCF? in South Africa to date is reviewed and plans for the introduction of PCF? excavation in other areas are highlighted.

Oct 1, 2001

By Kenneth G. Skinner, Hewitt Wilson, Thomas L. Hurst

Although chromite deposits occur in California , Oregon, Washington, Montana, Wyoming , Pennsylvania, Maryland , New Mexico , North Carolina, Alaska, and the Phillippine Islands , less than 1 percent of the ore used in the United States is obtained from these deposits . Most of the ore in peacetime has been supplied by imports from South Africa, New Caledonia, Turkey, and Cuba . The mineral chromite , the most important chromium ore , is an isometric spinel with an ideal composition of FeO Cr2O3 , but commercial chromite has the variable composition (Fe , Mg) Oʻ (Cr , Al , Fe) 203. Chromite has a black color , a specific gravity of 4.4 , and a hardness of 5.5 . In thin section the color is reddish -brown to black . Chromite occurs in dunite and pyroxenitic ultrabasic rocks , which are composed of iron- magnesium silicate minerals such as olivine , saxonite , serpentine , and enstatite . These are also the gangue minerals . Com mercial ore occurs at random in the country rock in kidney- or lens - shaped deposits , which have no apparent relationship to each other . Stringers , veins , and bands often cut the country rock without regard either to fracture or to other deposits . Some beach sands , such as those in southern Oregon, contain chromite .

Mar 1, 1943