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By Sang-Beom Lee

For thermodynamic prediction, the deoxidation equilibrium of aluminum in Fe-36%Ni alloy was studied with a cold crucible under Ar gas atmosphere at 1773K. For the deoxidation reaction in liquid Fe-36%Ni base, i.e.: A12O3(s) = 2A1 + 3O The interaction parameters and the equilibrium constant between aluminum and oxygen in liquid Fe-36%Ni alloy are given in the following: eo Al = -3.8, roA1=0.9, eAl° = -6.4, rAl° = 700, rAIAIo = 3.1, roA1o = 833 within the composition range of [Al] < 1 mass%. The temperature dependence of the equilibrium constant was obtained in the range of 1773K < T < 1973K by using reported data and present results as follows: log KAo= 0.58-24463.7 / T The deoxidation equilibrium with aluminum in Fe-36%Ni could be thermodynamically well described in the range up [Al] < 1 mass% with first and second order interaction parameters as well as the equilibrium constant determined in this study.

Jan 1, 2002

By K. E. Haque

"This paper is a brief overview of the role of oxygen in cyanide leaching of gold feeds (e.g. ore, concentrate). As the majority of gold occurs in the elemental state (Au °), its oxidation is of vital importance for dissolution in the cyanide lixiviant. The cyanidetion at high pH is favourable for the oxidation of Au° with a mild oxidant such as air or oxygen. Beside oxidation of gold, deleterious effects of soluble sulphides, arsenates, antimonates on cyanidation of gold can be alleviated by preaerating the leach slurry with air or oxygen (i.e. preaeration process).If gold is refractory due to its occlusion in sulphides, silicates, tellurides, etc. then gold liberation is possible by roasting in the presence of oxygen or by leaching under oxygen pressure. The data in the recent literature indicate that reactive oxygen supplied by H202, Na202, Ca02 or 03 during cyanidation can accelerate considerably gold oxidation-cyanidation and yield high gold recovery in much shorter leach time. The information compiled in this review leads to the conclusion that oxygen plays a vital role in the dissolution of gold in cyanide lixiviant."

Jan 1, 1992

Automation in underground mining enhances safety and leads to economic efficiency. In the past many efforts have been made on the automation of longwall shearer operation. With respect to the ultimate goal of automation, ie self controlled operation, coal bed boundary detection is one of the key problems. For longwall human labor is necessary in order to detect the exact position of the coal seam to be excavated. The authors present a sensor concept based on infrared technology and pattern recognition which will solve this problem. The very harsh underground conditions set high demands on the implemented sensors. The combination of infrared sensors and powerful processing algorithms is part of the innovative concept for automation of the new Eickhoff Bergbautechnik GmbH SL 750 shearer loader. The multi-sensor automation system EiControlPlus which is designed for the complete detection of the machine environment fills in the gap in the coal-excavation automation by building a recognition system that turns the shearer loader into an &apos;intelligent machine&apos; which is capable of detecting the correct position of the seam to be excavated and thus enables human-free coal mining.

Dec 6, 2010

By Luck D

Current methods of mucking out small development tunnels are a major limitation to improved efficiency and high rates of advance. This is particularly true in the deep metalliferous mines of South Africa, where the harsh environment, remoteness of operations and the hard abrasive rock conditions mitigate against the use of the tunnel borer type of equipment. The Loader Distributor Train was designed to overcome the special problems of hard rock tunnelling. It combines advanced innovative technology with proven simple methods of operation and maintenance. The system aims at taking advantage of new, efficient and cost effective power sources in South African mines based on replacing compressed air with electro hydraulics and the new concept of hydropower. It also introduces electronics and computer technology, for both automatic control and fault finding, into the production environment. The system is designed to permit sophisticated equipment to be operated and maintained by a semi skilled labour force. Although still undergoing trials it is believed that the Loader Distributor Train will prove highly effective, and that the new concepts offer considerable potential in areas other than flat tunnels, in particular the cleaning of inclined shafts.

Jan 1, 1986

By A. V. Tarasov

In order to improve technical, economic and environmental performance of hydrometallurgical processing of intermediate products containing copper and nickel, the Gintsvetmet Institute and the IMET Institute of the Russian Academy of Sciences have conducted studies into the efficiency of the use of alternating current of industrial frequency on processes applied for hydrochemical leaching of various copper- and nickel-containing materials. It has been found that: 1.Imposition of alternating current over the process of leaching of softly reduced nickel oxide with recycled copper sulfate solutions resulted in an increase by 20 to 30% of the rate of the copper cementation process and reduced by 20% its activation energy. At the same time, the recoveries of nickel, cobalt and iron to the leach solution increased up to 82.2%, 78.5% and 57.1%, respectively, and that of copper to the cement precipitate up to 74%. Optimal process conditions have been identified with respect to the current density, electrode material, copper concentration in solutions and the process temperature. 2.In the process of hydroelectrochemical sulfuric acid leaching of nickel and copper sulfides, the grain size, the phase form of sulfides, the solution composition (H2SO4, Cl?, Cu2+, Fe3+)and the current amperage had an effect on the nickel recovery to the solution, which reached 90%, while the degree of copper transfer to solution did not exceed 20%. The process of hydroelectrochemical sulfuric acid leaching of nickel and copper sulfides with an addition of Cl? made it possible to selectively recover nickel into the leach solution along with concentrating copper in the leach residue. 3.When subjecting samples of commercial-grade magnetic fractions of converter matte to sulfuric acid leaching, the imposition of electric current, the concentrations of sulfuric acid and chloride ion in the solution and the duration of the reaction process had an effect on the process. The nickel recovery was 85% and that of cobalt and iron was 95% and the recoveries reached 97.5%, 98.3% and 99.8% as a result of repeated treatment of the primary residue under similar process conditions. Up to 75% of copper, 75% of sulfur and 99.0-99.5% of palladium was concentrated in the solid reach residues. The experimental data obtained indicates that the use of AC for hydroelectrochemical sulfuric acid leaching for separation of copper- and nickel-containing intermediate products has favorable prospects.

Jan 1, 2003

By T. Yoshida

The Ni-MH (nickel metal hydride) rechargeable battery was developed several years ago. Its higher electrochemical capacity and greater safety compared with the Ni-Cd rechargeable battery have resulted in very rapid Increase in its production. The Ni-MH rechargeable battery consists of Ni. Co and rare earth metals, so that recycling is important to recover these valuable mineral resources. In this study. a basic recycling process for used Ni-MH rechargeable batteries has been developed, in which the Ni. Co and rare earth elements are recovered through a combination of mechanical processing and hydrometallurglcal processing.

Jan 1, 1995

By J. T. Eash, E. M. Wise

MANY of the platinum metal alloys are hot-forged in the early stages of reduction from ingot and substantial quantities of platinum alloys are commercially employed at very high temperatures in ammonia oxidation units, orifices for forming glass rods and fibers and as cathodes in long-life thermionic amplifiers. They are used also for electrical heating resistors, safety blowout disks, thermocouples and crucibles. The tensile properties at elevated temperatures are important in many of these situations but data on the subject are limited. Creep data also are important, but will not be covered at this time. SCOPE AND CONCLUSIONS Tensile tests were carried out at room temperature and elevated temperatures up to 11000 C. on previously well annealed samples of platinum, palladium and several of their important alloys with compositions shown in Table 1. The results are presented graphically in Figs. 1 to 4. The tensile strengths of platinum and the platinum-base alloys (with the exception of the 10 per cent rhodium-platinum alloy) at 1100° C. are from 16.6 to 18.8 per cent of the strengths of the same alloys (well annealed) at room temperature. The strength ratio of the 10 per cent rhodium-platinum alloy is 22.3 per cent, which is appreciably higher than that of the- other materials tested. The tensile strengths of palladium and the palladium alloy at 1100° C. are from 10 to 11.2 per cent of the room-temperature values. The elongations of platinum and its alloys tend to increase at tempera¬tures above 600° to 800° C., while the two samples of pure palladium show a maximum at 600° C.

Jan 1, 1938

By J. J. Demeter

A tube-wall reactor with a Raney nickel catalyst deposited on the outer wall of the tube by flame spraying is effective in the practically complete conversion of 3H2+1CO synthesis gas to a high-Btu gas (methane) at an hourly space velocity of 7,000 volumes of gas (NTP) per hour per volume of annular volume. Partially reacted synthesis gas containing an appreciable amount of methane can also be treated in this reactor to increase the heating value to over 900 Btu per cubic foot. Excellent heat removal through the metal wall to a coolant and temperature control were obtained. The heat transfer co-efficient from the catalyst to the coolant was about 275 Btu per hour per square foot per ° F. Synthesis tests were conducted with tubes 1.2 inches in ad by 6 inches long, and 1.3 inches in od by 36 inches long. When operating at a synthesis gas rate of 100 to 120 scfh per square foot of catalyst-coated tube, catalyst life was long enough to realize a catalyst cost for the raw Raney nickel alloy of about 0.3 cent per 1,000 cubic feet of pipeline gas (900 to 950 Btu per scf). Gas recycling at ratios of 1:1 to 3:1 was effective in increasing conversion and in extending the life of the catalyst to about 16 weeks. In cost and in operating characteristics the tube-wall reactor compares favorably with the fluidized-bed and hot-gas-recycle reactor systems for the synthesis of high-Btu gas from H2+CO.

Jan 1, 1967

By George S. Rice

IN other countries, research involving testing in various phases of ground movement and lessening its damaging effects, as by roof control, is going on more intensively than in this country, as evidenced by official mining papers and general articles appearing- in .Great Britain, Germany, France, and South Africa. One most important bulletin, "Some Aspects of Deep Level Mining on the Witwatersrand Gold Mines with Special Reference to Rock Bursts,"&apos; was published by the Association of Mine Managers of the Transvaal, Johannesburg, under date of June, 1933, though not received in this country until 1.934. Since the deepest mining in the world is being done on the Rand-several mines over 7000 ft. deep and the Robinson mine 8000 ft.-the studies made are of intense interest to all mining men who have to deal with heavy ground pressure. In the discussion following the papers differences of opinions are shown on a number of problems; for example, on the ade¬quacy of sand-filling to prevent rock bursts and whether compressible or rigid artificial supports are best; also whether pressure bursts are due to the doming of strata and collapse of a lag of the dome or to induced shear cracks in the hanging wall. The problem of obtaining some means of warning of an impending rock burst led to testing with height indicators to find whether warning might be obtained by the lessening of distance between hanging wall and footwall. The indicators used are similar in idea but not in detail to the "convergence recorders" developed by the Safety in Mines Research Board of Great Britain for their roof-control studies in coal mines. Success at several Rand mines is claimed in that indicator records give some degree of warning when the lessening of height is rapid, although, on the other hand, when this happens bursts do not always occur.

Jan 1, 1935

By Don Hickey

The MTA in conjunction with LIRR, are in the process of expanding one of the largest commuter railroads in the country, with over 260,000 passengers a day. The LIRR, which provides 700 passenger trains every 24 hours, can?t continue on the present growth course as a joint tenant in Penn Station with Amtrak and NJT. For this reason, in conjunction with the fact that over 53% of LIRR?s current riders into Penn Station are ultimately bound for the East Side of Manhattan opening, have created the need for the expansion of the LIRR. The complete expansion will cost approximately 6.3 billion dollars and all of the contracts are to be completed by 2013.

By K. H. Singh

The addition of new data and corrections can be made under the control of a simple editing session. All programs for this system are written in FORTRAN and executabe "MACROS".. After the addition of new data, the whole file Is reinitialized to update the binary file and cross-reference tables. Updating the binary file involves rerunning the initializing program. The creation of graphic plots like cross sections and plan views is menu-driven from a terminal and very user-friendly. Small files containing not more than 10,000 entries (survey and assay points) are suitable for this setup, particularly for computers with less than 2 Megabytes of real and virtual memory. The largest file processed contained 35,000 lines of survey and assay information and required 4 megabytes of virtual memory. Working with this size file slows down the time for the creation of plots and cross sections. Another independent system is more akin to a financial type of data base. It was installed in one Anaconda mine as part of the operation&apos;s inventory, warehouse, day-pay payroll, and purchasing data bases. It is a highly hardware-dependent system, in particular, IBM&apos;s CICS/VS (Customer Information Control System/Virtual Storage). This is a true relational data base that optimizes storage requirements, supports online inquiry, update, data entry, and data security. While this system has been tested and proven in accounting applications, it requires programming expertice in PL/I and other CICS utility programs. It is well suited for huge data bases (like the 35,000 lines of data), but cumbersome for small engineering files.

Jan 1, 1985

By Robert L. Rough, William E. Eckard

Laboratory data obtained from a Bureau of Mines rotary air core of a well near Sugar Grove , Warren County , Pa . , were instrumental in initiating hydraulic fracturing in the area to stimulate oil recovery from Glade sand oil reservoirs . This report outlines the general geology , lease development , reservoir- rock characteristics , and oil - production history of Glade and Clarendon sand reservoirs in Warren County . The methods of well completion for single- stage and multiple- stage hydraulic fracturing of old and new wells are discussed , and a range of hydraulic fracture treatment data from 29 Glade sand and 10 Clarendon sand wells is presented . A composite decline curve representing oil - production data from six wells shows probable results of hydraulic fracturing . Average cumulative oil production during the first 100 days after hydraulic fracturing with a sand - carrying liquid is compared with production after conventional shooting with liquid nitroglycerin .

Jan 1, 1964

By Carlton D. Hulin

The usual concurrence in time and space of intrusive igneous activity, favorable structural disturbance and mineralization, which is so manifest in the mineralized district necessarily indicates a close interrelationship between these events. Evaluation of available evidence leads to the recognition that an appreciable time interval exists between the emplacement of the igneous intrusive and the formation of associated ore deposits. During this interval known portions of the intrusive are completely solidified, highly differentiated magma facies are injected as dikes, and important faulting occurs, which may fracture and shatter the solidified intrusive body. The highly differentiated dike types could only have originated in some deep portion of an underlying plutonic body that had reached an advanced stage of magmatic differentiation. Appearing after these dikes, the mineralizing solutions may likewise be presumed to have originated at great depth. Certainly no source for these solutions can be found in near-by portions of the intrusive igneous body. The association of igneous intrusives and clustering ore deposits must be recognized as resulting from structural control. The emplacemerit and the subsequent solidification and cooling of the intrusive set in operation forces that are responsible for the favorable structural disturbances that control the mineralized district. The emplacement of the body of fluid magma weakens the crustal rocks to the extent that failure due to strains originally present in the rock body may occur. Faulting of any type and of any magnitude may be the result. Subsequently, owing to the change of state from fluid magma to crystalline granitic rock, volume decreases approximating 10 Per cent may Occur, with resultant shrinkage and collapse within the rock body. Following solidification, thermal contraction, induced by cooling of the rock body, causes a further volume reduction of 6 per cent. This thermal contraction, extending over a lengthy period of time, results in a succession of minor fault movements. These small fault movements, occurring progressively throughout the period of mineralization, are responsible for maintaining the permeability of the rock body, without which access of the mineralizing solutions and the formation of the ore deposits of the mineralized district would be impossible. Introduction A proper understanding of the causes that have localized our mineralized districts should be of considerable value to geologist and engineer alike. under current conditions the known ore reserves of productive mining camps are being rapidly depleted. Although ore of the future will be derived in part from deposits now known and from Ore bodies that are still to be discovered within the limits of productive mining districts, in part at least it must come from mineralized districts whose existence or importance yet remain to be recognized. The mining geologist is thus faced with two problems of paramount importance: (I) the location of new ore bodies within known mineralized areas and (2) the location of new mineralized districts within whose confines, previously unknown, valuable Ore deposits may occur. Any contribution to our knowledge concerning the causes for the localization of mineralized districts

Jan 1, 1949

By Carlton D. Hulin

The usual concurrence in time and space of intrusive igneous activity, favorable structural disturbance and mineralization, which is so manifest in the mineralized district necessarily indicates a close interrelationship between these events. Evaluation of available evidence leads to the recognition that an appreciable time interval exists between the emplacement of the igneous intrusive and the formation of associated ore deposits. During this interval known portions of the intrusive are completely solidified, highly differentiated magma facies are injected as dikes, and important faulting occurs, which may fracture and shatter the solidified intrusive body. The highly differentiated dike types could only have originated in some deep portion of an underlying plutonic body that had reached an advanced stage of magmatic differentiation. Appearing after these dikes, the mineralizing solutions may likewise be presumed to have originated at great depth. Certainly no source for these solutions can be found in near-by portions of the intrusive igneous body. The association of igneous intrusives and clustering ore deposits must be recognized as resulting from structural control. The emplacemerit and the subsequent solidification and cooling of the intrusive set in operation forces that are responsible for the favorable structural disturbances that control the mineralized district. The emplacement of the body of fluid magma weakens the crustal rocks to the extent that failure due to strains originally present in the rock body may occur. Faulting of any type and of any magnitude may be the result. Subsequently, owing to the change of state from fluid magma to crystalline granitic rock, volume decreases approximating 10 Per cent may Occur, with resultant shrinkage and collapse within the rock body. Following solidification, thermal contraction, induced by cooling of the rock body, causes a further volume reduction of 6 per cent. This thermal contraction, extending over a lengthy period of time, results in a succession of minor fault movements. These small fault movements, occurring progressively throughout the period of mineralization, are responsible for maintaining the permeability of the rock body, without which access of the mineralizing solutions and the formation of the ore deposits of the mineralized district would be impossible. Introduction A proper understanding of the causes that have localized our mineralized districts should be of considerable value to geologist and engineer alike. under current conditions the known ore reserves of productive mining camps are being rapidly depleted. Although ore of the future will be derived in part from deposits now known and from Ore bodies that are still to be discovered within the limits of productive mining districts, in part at least it must come from mineralized districts whose existence or importance yet remain to be recognized. The mining geologist is thus faced with two problems of paramount importance: (I) the location of new ore bodies within known mineralized areas and (2) the location of new mineralized districts within whose confines, previously unknown, valuable Ore deposits may occur. Any contribution to our knowledge concerning the causes for the localization of mineralized districts

Jan 1, 1949

By Helge Rosenberg

Up to now, Topsøe WSA (Wet gas Sulphuric Acid) plants have been in operation for almost 30 years, and close to 80 plants have been sold. In spite of its unique features and ability to treat gases without any prior drying, the WSA technology has had certain restrictions with regards to SO2 concentration in the feed gas, and the overall conversion of SO2 by catalytic means has been limited to approx. 99.7%. In commercial scale sulphuric acid production on the basis of elemental sulphur and metallurgical off-gases, there is a demand for higher SO2 conversion and treatment of gases with a higher content of SO2. Therefore Topsoe has further developed its WSA technology to cope with these demands. This paper will explain more about the principles of such new development and leave the delegate with a better understanding of the potentials of the new generation of the WSA technology from Topsoe.

Jan 1, 2009

By S. L. GILLAN

OF the forty or more excursions provided for the delegates to the World Engineering Congress at Tokyo, the trip to the Ashio copper mine stands out as one of the most enjoyable. In every detail looking to our comfort and pleasure the Furukawa company, our hosts, were admirable. This company operates five other copper mines, also gold and coal mines. Ashio is the largest with an annual production of about 14,000 tons of copper. It has been continuously worked since 1620, and doubtless was one of the sources of copper used in the gigantic statues of Buddha of many hundred years earlier date.

Jan 1, 1930

By R. K. Mehta

Stirred ball mill feed used for ultra-fine grinding application requires fine size separation step in order to avoid over-grinding. This paper presents the selectivity curves obtained for oil shale and complex sulfide are using 460 mesh (30 micron) Derrick vibrating screen. Interestingly, the selectivity curves generated from the experimental data were monotonic increasing selectivity for oil shale but not monotonic increasing for sulfide ore. These non-monotonic increasing selectivity curves were similar to the mechanical air separator fishhook selectivity curves described by Luckie and Austin. A 2 stage classification in series model describing the fishhook selectivity curve has been used in proposing the classification mechanism for fine vibrating screens when heterogeneous multicomponent sulfide are undergoes size separation.

Jan 1, 1992

By J. F. Wolff

The iron formation of the Gogebic Range in northeastern Wisconsin and the northwestern part of the Upper Peninsula of Michigan, resembles that of the Mesabi Range in Minnesota very closely in lithologic character and the subdivisions and horizons that can be recognized. It contains numerous interbedded slaty layers and considerable intraformational conglomerate in certain horizons. In contrast to the flat dip of the Mesabi formation, the Gogebic dips steeply to the northwest at an average angle of about 70". It has a quartzite and siliceous slate foot wall and a hanging wall of conglomerate, graywacke and slate. The black and gray Tyler slate has been designated the hanging wall of the Gogebic iron formation in U. S. Geologicial Survey monographs, but between the true Tyler slate and the commercially important Gogebic iron formation, and apparently unconformably upon the latter, is a series 600 ft. or more thick of conglomerate, slate, graywacke, and cherty iron formation, the latter being of no commercial importance on the Gogebic Range as far as now known. This series is probably that described as the "Capps" on the eastern Gogebic by the Michigan Geological Survey. The Gogebic iron formation proper can be subdivided into three main horizons, a lower cherty and an upper cherty with a banded or slaty horizon between them, corresponding to the three lower horizons of the Mesabi. Several minor subdivisions can be made of these major ones. Orebodies occur in all three horizons of the Gogebic series and in some places ore is developed across practically the entire series. Dikes and Sills The Gogebic iron formation has been intruded most intricately by basic dikes and sills, most of the former pitching east but some pitching west. One very extensive sill is intruded near the base of the lower slaty or banded horizon, in the formation known locally as the Yale slates. One extensive bedding or strike fault is associated with this sill and a great many transverse faults occur at different places along the Range. The combination, or association, of steep dip, faults, dikes and sills has produced conditions very favorable for the development of orebodies through the leaching, oxidation, and consequent concentration effected

Jan 1, 1925

By R. L. Virta

Editor?s note: Each year, the June issue of Mining Engineering features an industrial minerals review. Several people put in a fair amount of time in developing the material for this issue. Thank you to the industrial minerals annual review editor, to the technical committees chair and vice-chair, and to the authors of the individual commodity profiles. Jim Norman, member SME, of GeoTrans Inc., is the industrial minerals annual review editor. Abani Samal, member SME, of Pincock Allen & Holt, is chair of the industrial minerals technical committees. Technical committee vice chairs include: ? Abani Samal, member SME, of Pincock Allen & Holt, agricultural minerals. ? Aaron McMahon member SME, of Pincock Allen & Holt, ceramics and refractories ? Bradley S. Van Gosen, member SME, of the U.S. Geological Survey, chemical raw materials. ? Mark Zdunczyk, member SME, of Continental Placer Inc., construction materials. ? Jerry Gauntt, member SME, of Marston, fillers and pigments. ? Michael Cheshire, member SME, of Indiana University, sorbents, filters and process aids. ? Candace Trimble, Oil-Dri Corp. of America, specialty minerals. Their help makes possible this June industrial miner-als issue. On behalf of ME readers, the editors thank them. Ball Clay Four companies ? H.C. Spinks Clay (owned by Lhoist Group), Kentucky-Tennessee Clay (owned by Imerys Group), Old Hickory Clay, and Unimin Corp. ? mined ball clay in four states in 2008. Production, on the basis of preliminary data, was 964 kt (1.1 millon st) with an estimated value of $45.3 million. That was a 10- percent decrease in tonnage from 1.07 Mt (1.2 mil-lion st) with a value of $49.2 million that was produced in 2007. Tennessee was the leading producer state with 63 percent of domestic production, followed by Texas, Mississippi and Kentucky. About 73 percent of production was airfloat, 16 percent was crude and 11 percent was water-slurried.

Jan 1, 2009

By S Lakemond, L I. Ku, J Vaughan

Conventional processing of poly-metallic gold containing flotation concentrates are challenging for a number of reasons. One reason is that substantial copper and zinc in the cyanide leach solution compete with gold and silver for carbon adsorption sites. In this study, metal-cyanide adsorption kinetics and equilibrium are measured on three samples of coconut derived activated carbon and one sample of synthetic carbon. Loading selectivity was confirmed to be in the order gold&gt;silver&gt;copper&gt;zinc for all carbon samples. The synthetic carbon tested showed promising results in terms of loading kinetics and capacity for precious metals.CITATION:Lakemond, S, Ku, L I and Vaughan, J, 2013. Effect of carbon type on adsorption of Cu, Zn, Ag and Au from mixed cyanide solution, in Proceedings World Gold 2013 , pp 411-418 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013