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By Rajesh Kumar Mishra

About 500,000 troy ounces of Platinum Group Metals (PGM) will be available for recycling each year from spent automobile catalytic converters in North America alone. Platinum Group Metals? from spent catalyst can be extracted by Hydrometallurgical, Pyrometallurgical or Gas Phase volatilization processes. This paper is a review and comparative study of various processes investigated for PGM extraction. A number of processes described in this paper have already been commercialized. The technical and environmental aspects of the important processes are discussed.

Jan 1, 1989

By Joseph E. Pogue

The writer visited the Muzo emerald mines in July, 1915, and spent six days in their study. This paper embodies the results of his observations, plus information personally communicated by Robert Scheibe, Professor of Geology in the Mining Academy of Berlin, who at the time of the visit was completing a detailed field investigation of nearly a year's duration of the emerald deposits of Colombia. An elaborate account of this valuable work may be expected at a future date from the pen of Professor Scheibe.

Jan 1, 1917

By E. Maltby Shipp

YouR committee's secretary submits the following report, or summary, to the members of the committee, in an endeavor to lay before them a general review of the information so far received and also his own knowledge of the work as carried on at a number of plants, this being done in part to secure further information and suggestions from members and lead to a more effective means of furthering the work of the committee. It is suggested that more detailed data be compiled regarding engineering features involved, and that papers be contributed which will deal with the safeguarding of underground electrical installations. There are few operating companies which have not started a more or less systematic campaign to safeguard their employees from accidental injuries and unhealthful surroundings, but a great deal is to be gained by experience. All may welcome the advice and cooperation of those who have been actively engaged in the work and have demonstrated the results obtainable by organized effort, and it is, therefore, exceedingly gratifying to note the ready assistance and hearty cooperation rendered by the companies that may be truly termed pioneers in the movement. No solution of the safety problem is to be found in a skrict standardization of methods, rules or devices, as the various mining, milling and metallurgical practices present too many conditions differing broadly in general principles, but some standard system embodying principles already proven to be efficient should be created, which may be modified or elaborated to meet specific requirements of each individual company, or to fit working conditions as they exist in the various mining camps throughout the country. An industrial plant is primarily a business undertaking, therefore the economic side of a safety or welfare campaign is of importance. Many small operators have been deterred from undertaking the work by their belief that it involved an expense beyond their means, and one that could not be counterbalanced by greater efficiency or saving along other lines. This idea is generally due to a lack of knowledge of the actual costs of such work, and of the results secured by judicious selection of a method commensurate with the size and nature of the opera-

Jan 1, 1918

By T. T. Ni

FOR MORE THAN 200 years, the Kochiu district of Yunnan province has been, and it still is, the hub of China's tin industry. The district produces annually from 80 to 90 per cent of that country's out-put of tin, which averages about 9,300 tons a year and places China fifth among the tin producing nations of the world. The tin ore reserves of the country are estimated (1) at 1,873,370 metric tons, of which 1,500,000 tons are in the Kochiu district. The mill of the Yunnan Consolidated Tin Corporation, described in this paper, is the only one of its kind in China. MINING AND SMELTING There are only two tin mines in the Kochiu district operating with modern equipment -the Hsin-Chang and the Lao-Chang, both owned by the Yunnan Consolidated Tin Corporation, a government company. The Hsin-Chang mine has four working levels with cross-cuts 6 ft. by 6 ft. and is equipped with steel mine cars and trucks to haul the ore. The ore is hoisted to surface in a three-compartment shaft and transferred to the mill by a 4-kilometer aerial tram. The Lao-Chang mine has two circular shafts 656 feet apart, each equipped with two cages. Haulage-ways 1,600 meters and 1,000 meters long, respectively, have been driven to the southwest from these shafts and are connected by three cross-cuts.

Jan 1, 1951

By William D. Riley

In order to evaluate the corrosion resistance of zirconium in mineral extraction processes, such as a clay-hydrochloric acid leaching process for extracting alumina, the Bureau of Mines conducted corrosion studies in HCl-AlC13-FeC13 environments. A series of weight loss and electrochemical tests were conducted at 25° and 65° C in aluminum chloride (AlC13) plus hydrochloric acid (HCl) solutions containing 0 to 1,000 ppm ferric ion. It was determined that zirconium, which normally exists in a passive state in chloride-containing solutions, undergoes pitting attack in solutions containing more than 100 ppm of ferric ion. It is also shown that an oxide film prepared in air at high temperature offers protection in acid solutions containing levels of ferric ion from 300 to 1,000 ppm.

Jan 1, 1981

By N. V. Melnikov, L. N. Marchenko

The latest theoretical and experimental study of physical processes initiated by explosions in solid media have made it possible to obtain a deeper insight into the mechanism of the energy transfer to ambient rock from char es of explosives interspersed with various air gaps. As shown in (17, high explosive action causes excessive fragmentation of medium in the vicinity of the charge, while expansion of the process into the massif is negligible. A theoretical outline of a more rational application of explosion energy was given with a view of obtaining more uniform fragmentation of rock convenient for loading and transportation. The proposed idea proven by experimental study consisted of the possibility of explosion control based on redistribution of explosion energy. Practical realization of the above idea was proposed (1) involving charges with air gaps for rock fragmentation. Since the Rolla Symposium on Mining Research (USA, 1961) (2), borehole charges with air gaps have become common practice. This method of rock blasting is applied in open cast and underground mines working the hardest and viscous, hard, medium hard and soft rocks (ore, quartzites, granites, 1 imes tones, sandstones, coals, etc.) as well as at enterprises for extraction of building materials and raw chemical minerals of any strength. Application of charges with air gaps results in an increase of the degree and uniformity of fragmentation (up to 94 percent of the blasted rock mass consists of fragments not exceeding 400 mm), the average fragment size decreases by 1.5-2 times and the amount of lumps is reduced by 2-10 times (in some cases there are no lumps at all ). Besides, the amount of operation for filling boreholes with tamping material is reduced, the specific consumption of explosives

Jan 1, 1971

By Kenneth Williams

Economic drives dictate the exploitation of formerly less attractive ore bodies located close to or even beneath the water table. These ores can cause handling problems and expensive downtime of processing equipment due to their increased adhesive characteristics and are colloquially termed as “wet and sticky” ores. In order to gain a better understanding of the causes of poor handleability, experimental test methods for wall and inter-particle adhesion within bulk solids samples were developed and validated. The results confirmed that adhesion of bulk solid to equipment surfaces is mainly governed by capillary pressure. It can therefore be described using the Young-Laplace equation, which implies that adhesion is primarily dependent on the interfacial water between bulk material and the adhesion partner. Accordingly, the governing material parameters of adhesion are its capillarity and permeability, as these two characterize water transport to or from the interface of the adhesion partners. Furthermore a threshold for the classification of a material as wet and sticky based on the measurements of adhesion has been proposed.

Aug 17, 2017

By R. Bruce Tippin

because of the mineral's high monetary value and the spotty occurrence of free gold in the deposit. Setting up a plant sampling procedure by simply applying the usual statistical sampling theory was questionable. Two sampling concepts were considered in the sampling study: o a sufficient number of assays can be taken such that the average determined from these individual samples represents a known quantity of ore. o a sufficient weight of sample can be taken such that when assayed it represents a known quantity of ore. The test program included evaluation of sampling techniques, sample preparation and analytical methods. The overall sampling program is depicted in Figure 2.

Jan 1, 1985

By Wenya Du, Qingbo Yu, Peng Li, Qin Qin

"A new heat recovery system is proposed. This system uses the endothermic heat of gasification reaction instead of sensible heat to recover the energy of molten blast furnace slag. The gasification technological parameter in molten blast furnace was calculated and the exergy of the system was analyzed. The gasification reactions were studied kinetically by the isothermal thermogravimetry using STA409PC thermal analyzer. The results showed that, according to different gasification agent, this system can produce syngas with different C-H ratio. The exergy efficiency of this system is high and its internal exergy loss rate is about 11%. This method can bring huge economic and environmental benefits which are important to the survival and sustainable development of iron-steel enterprises. The molten BF slag acts as not only thermal media but also good catalyst. The kinetic parameters on gasification reaction with different types of coal used differ from each other.IntroductionEnergy consumption in the iron-making process is about 50%~60% of the total energy input. The blast furnace is very important in the iron & steel process. So energy conservation and emission reduction about blast furnace is very important. In recent years, in order to recovery energy, many new technologies such as TRT (Top gas pressure Recovery Turbine) and CCPP (Combined Cycle Power Plant) were used in iron-making. But the energy of molten blast furnace (BF) slag has only been used limitedly so far.Molten BF (Blast Furnace) slag is the byproduct of iron-making at the high temperatures range from 1723 to 1923K, and has a large amount of sensible heat remaining. The yield of molten BF slag is about 300 kg per ton of pig iron. In conventional processes, molten BF slag is quenched rapidly using a large amount of water to produce a glassy-granulated slag. The quenching slag must be dried before it can be used in cement manufacture. During the process, a large amount of water was consumed and the energy of molten slag can not be recovered. At the same time, it causes environmental pollution problems. So the critical problems of the process are not only energy recovery of molten slag and reducing emission of H2S and SO2, but also guaranteeing the subsequent use value of slag. For this propose, many new technologies were investigated to recover the thermal energy of molten slag. The promising methods are dry granulation [1-4] and reforming of methane [5-9]. The method, utilization of reaction heat instead of latent heat and sensible heat, is quite attractive from viewpoints of energy storage without heat loss, and makes a connection to other industry. But both of them are in laboratory. In this paper, coal gasification in molten BF slag was used to recover the energy of molten BF slag. The gasification technological parameter in molten BF was calculated and the exergy of the system was analyzed. The gasification reactions were studied kinetically by the isothermal thermogravimetry using STA409PC thermal analyzer."

Jan 1, 2011

By Edmund S. Leaver

The Precious Metals Section is concerned primarily with ore-testing problems associated with precious metals and with the analysis and concentration of a large number of the strategic-mineral samples that have been included in the research program of the Bureau of Mines. During the fiscal year 1938-39, 30 projects were completed. The requests for this service are based upon the desire of the sponsor to obtain the best or most satisfactory method for maximum recovery of the minerals. In many instances it is a question of improving present milling practice, with due regard to utilization of present equipment. In others, the probable tonnage available maybe the deciding factor in the choice of a particular recovery method. Under all circumstances the results of tests axe prepared with the thought of aiding a competent metallurgist, familiar with local conditions, to formulate a practical flow sheet or to assist the mill operator to correct known losses. A microscopic examination for identification of the mineral constituents and their association in each ore is always a big help, in planning the tests and may indicate the reason for former troubles or assist with best procedure.

Jan 1, 1940

By Edmund S. Leaver

The Precious Metals Section is concerned primarily with ore-testing problems associated with precious metals and with the analysis and concentration of a large number of the strategic-mineral samples that have been included in the research program of the Bureau of Mines. During the fiscal year 1938-39, 30 projects were completed. The requests for this service are based upon the desire f the sponsor to obtain the best or most satisfactory method for maximum recovery of the minerals. In many instances it is a question of improving present milling practice, with due regard to utilization of present equipment. In others, the probable tonnage available maybe the deciding factor in the choice of a particular recovery method. Under all circumstances the results of tests axe prepared with the thought of aiding a competent metallurgist, familiar with local conditions, to formulate a practical flow sheet or to assist the mill operator to correct known losses. A microscopic examination for identification of the mineral constituents and their association in each ore is always a big help, in planning the tests and may indicate the reason for former troubles or assist with best procedure.

Jan 1, 1940

By Sherwin F. Kelly

THE joint meetings of the Mining Geology Committee and the Society of Economic Geologists proved to be deservedly popular, and the interesting papers drew an attendance which strained the capacity of one of the large meeting rooms.. As might be expected these days when even the Supreme Court can't keep away from the subject of gold, the discussions opened on Thursday morning with several papers devoted to questions of structural and mineralogical relationships of the deposits of this metal. The presentation of Ira B. Joralemon's paper, "Veins and Faults in the Bralorne Mine," by Reno Sales, elicited considerable discussion on the relation of mariposite to gold, and the situation of the gold deposits with respect -to the Coast Range batholith. H. V. Warren stated that lie had observed mariposite always to be associated with gold in this region, but that gold was not always associated with mariposite. He pointed out that there is a series of veins on the west side of the batholith with a different mineralogy that, because of their richness but small size could quite easily make good, small mines. John A. Dresser concurred in this, and said lie thought this region was one of great promise for the mining geologist. He also reported having found mariposite associated with gold values below commercial limits, in the Appalachian regions.

Jan 1, 1935

By R. H. Grau, A. Sainato, S. J. Schatzel, T. M. Kohler, A. T. Iannacchione

This Bureau of Mines research study found gas emission rates from an advancing face, and flows and pressure of gas from an exploration drill hole were dependent upon the geology of salt encountered in a domal salt mine. Normal production-grade "pure" salt adjacent to an anomalous' zone was found to have a methane emission rate of less than 5 ft3/ ton (0.1 m3/t) of mined salt from a room advanced by a continuous miner. Extremely low gas flows [less the 4 ft3/h (0.1 m3/h)] and lack of pressure buildup were also observed from this normal salt in a 154-ft (47-m) exploration drill hole. These data indicate that methane emissions should not be a problem when mining in this type of salt. In the adjacent anomalous zone, methane emission rates ranged from 15 to 70 ft3/ton (0.4 to 1.8 m3/t) of mined salt from an advancing face. Gas flows of approximately 42 ft3/h (1.2 m3/h), and pressures in excess of 900 psig (6,200 kPa) were observed in an exploration drill hole when the anomalous zone was encountered. This information suggests a greater methane emission hazard from the anomalous zone than from the associated normal salt. If this trend of increasing emissions problems associated with anomalous zones of salt is common with similar anomalous zones encountered or observed in other domal salt mines, then special control strategies should be employed to minimize this potential mining hazard.

Jan 1, 1984

By W. S. Landers

This bulletin is a detailed study of low-temperature, entrained-bed carbonization of a Texas lignite. The lignite studied was from the Sandow strip mine and is representative of the Rockdale formation of the Wilcox formational group. Carbonization was conducted in a continuous entrained-bed reactor at several temperatures in the 8801 to 1,52°C F range, and at air-coal ratios it the 0 to 10.30 scf/lb range (moisture- and ash-free basis). Carbonization rates ranged from 97.1 to 410.0 lb/hr (as-received basis), At the higher air-to-coal ratios employed, all or most of the carbonization heat was provided by internal combustion with air in the reactor. At the lower air-to-coal ratios, parts of the heat for carbonization was supplied externally. It was demonstrated that the entrained-bed carbonization of lignite is a complex reaction and that several variables, of which carbonization temperature, air-to-lignite ratio, and the average size of lignite are important, act together to influence both the carbonization yields and the properties of the resultant products, Process variables established by pant tests were used to design the industrial scale carbonizer operated at Rockdale, Texas, by the Texas Power & Light Company as agents for the Aluminum Company of America. Properties of the carbonization product obtained from the industrial scale reactor were essentially the same as those obtained from the pilot plant reactor operated under the same conditions.

Jan 1, 1968

By S. Viswanathan, Q. Han, A. S. Sabau

"In spite of recent advances in the mathematical modeling of fluid dynamics for materials processing applications, no significant advances have been made in the numerical discretization of these equations. In this work, the application of two-step projection methods for the numerical simulation of interdendritic flows is discussed. Unlike previous methods, the methods presented here are constructed for the exact equations which are characterized by variable density and volumetric fraction of the liquid. The drag terms, which describe the momentum loss due to the flow around and through the dendrite structures, are treated implicitly. Numerical examples for shrinkage-induced flow during solidification of an Al-4.5% Cu alloy bar is used to illustrate the effectiveness of the proposed algorithm.IntroductionLiquid contraction during solidification plays an important role in the formation of casting defects such as shrinkage voids, microporosity, and macrosegregation. Owing to their importance, the study of transport processes during solidification have received considerable attention during the past years [1, 2]. By the use of volume-averaging techniques, the mass and momentum equations for flow through a stationary dendritic structure were derived [3]. By using the volume-averaging techniques for multi-phase systems, two-phase transport equations for solidification problems were derived [4]."

Jan 1, 1999

By Marion Dattilo

The search for an improved anode for the electrowinning of lead from fluosi1icic acid medium has led the U.S. Bureau of Mines to investigate composites. Polymer bonded metal oxide powders which may contain catalyst additions were prepared by pressing. These composites display an improved activity toward the oxygen evolution reaction over electrodeposited lead dioxide on titanium, carbon, and nickel substrates. These composite electrodes contain 5 to 10 wt. " binding polymer, with the balance being metal oxides. Lowered anodic potentials achieved using the compnsite anodes resulted in lower levels of lead dioxide deposition during electrowinning.

Jan 1, 1995

By M. Muravyov, T. Kondrat’eva, A. Bulaev

Metallurgical treatments of sulfide ores containing copper and zinc are characterized by significant losses of base metals, particularly formation of the flotation tailings and slags during the dressing and pyrometallurgical treatment respectively. In addition, SO2 gas obtained during roasting and converting may be as raw material for sulfuric acid production. A treatment of the industrial metallurgical wastes has been investigated. Two samples of old pyrite tailings from two concentrators that contained 0.36% and 0.26% of copper and 0.23% and 0.22% of zinc were leached with 10% sulfuric acid in the column. Recovery of copper reached 47% and 38% while recovery of zinc was 47% and 41% from the first and second samples, respectively. The pregnant leach solutions contained 15.9 g/l and 10.5 g/l of ferric iron. Ferric iron is the strong oxidant and ferric containing pregnant leach solutions can be used for ferric leaching of different types of raw materials containing sulfide minerals. Therefore, ferric leaching of copper converter slag flotation tailings contained 0.53% of copper and 2.77% of zinc with the first pregnant leach solution was conducted. The effect of various experimental parameters on the leaching dynamics of copper, zinc, and iron under batch conditions was investigated. Under the best conditions (temperature 70oC, pulp density 30%) the recovery of copper and zinc reached 80% and 42%, respectively. Thus, it has been shown that acid leaching of base metals from old pyrite flotation tailings with using of the pregnant leach solution for the ferric leaching of copper converter slag flotation tailings is a prospective technique for the complex treatment of mining and metallurgical wastes. Investigated processes could be introduced into the technological flow-sheet of typical pyrometallurgical plants.

Jan 1, 2014

By Richard A. Heckman

Destructive Thermal Technology (DTT) is used in the management of various waste streams. DTT includes Destructive Distillation, Pyrolysis and Classical Incineration. Recent work has more clearly defined the differences in these technologies based upon a more rigorous thermochemical approach. The U.S. Environmental Protection Agency (EPA) has chosen Classical Incineration as the Best Developed Available Technology (BDAT) for the management of hazardous organic wastes. Municipal Solid Wastes (MSW) and Sewage Sludges (SS) are also managed using Classical Incineration. Three environmental problems plague the use of Classical Incineration. Destructive Distillation, on the other hand, avoids these problems. It is an environmentally benign DTT for managing a wide variety of organic waste streams, including hazardous wastes. Thermochemical analysis of the available data on the performance of three types of DTT will be discussed.

Jan 1, 1994

By C. C. Clark, D. J. Benton, J. B. Seymour, L. A. Martin

"The U.S. National Institute for Occupational Safety and Health (NIOSH) is conducting research on jackleg use and related accidents in underground metal mines. This paper provides an analysis and overview of jackleg drill usage, accidents, operational characteristics and alternatives, based on information from injury reports, legacy research, stakeholder input and published literature. The results indicate that jackleg drills are involved in more groundfall accidents in underground metal mines than any other drill, and jackleg-drill-related injuries are most prevalent at the face in the course of installing initial ground support. Practical mechanized alternatives to jackleg drills for drilling and bolting under incomplete support in narrow underground openings have not yet been realized. Small, versatile mechanized bolting equipment needs to be developed to address jackleg-drill-related accidents and improve safety at mines where jackleg drills are being used. IntroductionJackleg drill is a generic name for a handheld, rotary, percussion rock drill equipped with an attached reaction leg to provide stability and thrust (Fig. 1). All of the drill and leg controls are located near the operator’s handle at the rear of the head portion of the drill. Jackleg drills are classified according to the bore size of their pneumatic pistons, which normally range from 6.03 to 8.26 cm (2.375 to 3.25 in.) (Kurt, 1982; Clark, 2012). Jackleg drills typically weigh 46.7 kg (103 lb), but the weight can approach 54.4 kg (120 lb) after being fitted for operation with drill steel and air and water hoses (McKibbin and Clark, 2001). In underground mines, jackleg drills are commonly used to drill 3.8-cm (1.5-in.) diameter holes up to 1.83 m (6 ft) deep in rock."

Aug 1, 2016

By F. N. Siddiquie, Mohd Shaif, Rajiullah Khan, Juned Alam

Manganese ore bodies of Banswara Mn belt were classified into stratiform and stratabound types, based on their mode of occurrence, distribution, and their chemical characters. These ore bodies generally composed of braunite, pyrolusite, cryptomelane/ psilomelane, wad, etc. The stratiform-type Mn ore bodies are conformable with the associated host rocks (Mn phyllite, etc.) and occurred in the form of layers, bands, etc., which are variable in their shape and size. These ore bodies are also strongly folded with the enclosing host rocks. The others, which are stratabound-type Mn ore bodies, also showed an intimate association with the associated host rocks. These types of ore bodies occurred in thin layers, pockets, lenses, stringers, etc. The classified ore bodies are confined with Kalinjara formation of Aravalli Supergroup of Paleoproterozoic age. The ore bodies are structurally controlled and well associated with phyllite, schist, limestone, quartzite, etc. The stratiform-type ore bodies constitute a marginal to low Mn grade and are also characterized by lower Mn content (26.19–39.24%) along with the Mn/Fe ratio of 7.16–12.23, while the stratabound-type Mn ore bodies are rich in Mn (35.92–49.64%) along with the higher Mn/Fe ratio of 14.15–23.97. However, the poor Mn grade along with high siliceous impurities of Banswara Mn deposits is subjected to them for intermittent mining activities in the past and, consequently, did not attract the scientific and industrial community for the evaluation of these resources. Therefore, the authors attempted this study in a scientific and systematic manner (mode of occurrence/distribution and possible methods for evaluation/exploration) to evaluate the potential of existed and newer Mn deposit resources in the Banswara Mn belt. The whole findings would be very much helpful for exploration/ mining geologist along with other concerned, to completely evaluate these Mn deposits in the future.

Aug 16, 2021