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By Clyde S. Brooks

This paper undertakes to assess what opportunities exist for the economical recovery of non-ferrous metals from spent catalysts. The most promising recovery appears to lie with metals such as Co, Mo, Ni, W, heterogeneous catalysts used on a large scale in petroleum processing. Nickel is a metal with diverse applications on a large scale notably in hydrocarbon steam reforming and in vegetable oil hydrogenation. In addition, several of the precious metals, notably Pt, Pd, and Rh, find extensive use in fossil fuel processing and in automotive and power plant flue gas control. The hydrometallurgical and pyrometallurgical alternatives for processing are identified and discussed, especially with citations to illustrate reduction to commercial practice. Promising directions for adaptation of appropriate, economic separation technologies for recovery of non-ferrous catalytic metals generated in significant amounts for the secondary metal markets are identified. Recycling

Jan 1, 2000

The third session of the Rocky Mountain Coal Mining Institute was called to order by Edward G. Fox, President of the Bitumious Coal Operators' Association, Washington, D. C., at 9:M A.M. He stated he had enjoyed being present at the Institute the past two years, and was honored to be asked to preside at this morning's session. Mr. Fox introduced Cloyd M. "DOC" Smith, Vice President of World Mining Consultants, Inc., Washington, D. C., whose talk, "World Trade in Coal" was illustrated with a number of graphs. (See Index.) M. E. "Shorty" Wade, Assistant Purchasing Agent, Kaiser Steel Corporation, Fontana, California, was introduced and gave a paper on "What Is Required to Realize Profits Through Purchasing." (See Index.) Mr. Fox suggested that all members take an active part in their association. He stated that much more can be done in association work than as a lone wolf. He urged all to support their organization and stay with it. It is for each member's good and not for the good of a few. Carl G. Schilbe, District Manager, Jeffrey Manufacturing Company, Columbus, Ohio, was introduced, and he presented a paper on "Results of a Study in Belt Idler Design -The Perma-Seal Idler." This paper was illustrated with a number of slides. (See Index.) "Operation of A-C Mines," was the topic covered by W. C. Painter, Service Engineer, Joy Manufacturing Company, Price, Utah. (See Index.) Each of the papers was well received, and presented a number of things valuable to all who heard them. Mr. Fox then turned the meeting back to President von Storch who read several announcements of committee meetings, and the meeting was adjourned at 11:30 A.M. for an afternoon of recreation before the banquet and dance that evening.

Jan 1, 1958

By J. B. Clark, F. N. Rhines

brittlement or notch sensitivity progressively increases. Further, in contrast to results obtained with the impact test, the notch strength for the large specimens does not reveal a 500°F embrittlement range. The notch sensitivity as determined with the 0.3-in. specimen of 4340 steel given the stepped austenitizing treatment has been discussed elsewhere. This quantity as measured for the 1.1-in.- diam notch tensile test and given in Fig. 3, is taken to signify that reduced notch sensitivity is encountered in the 600" to 800°F tempering range for specimens given the stepped austenitizing treatment. The stepped austenitizing treatment may, there- fore, be of use in promoting deeper hardenability for a 4340 steel while at the same time giving reduced notch sensitivity in the high-strength range in which this steel is now being used. Acknowledgments The work reported was supported by the U. S. Navy Bureau of Aeronautics. The authors are indebted to the Bureau of Aeronautics for granting permission to publish results of this research and to N. E. Promisel, H. Hessing, and J. Maltz for their interest.

Jan 1, 1958

By M DellÆAmico, K Vining

The iron blast furnace is the most widely used and efficient producer of liquid iron; however, emissions from sintering and coking cause environmental pressure for the integrated steel works. The combustion of coke fines (breeze) during sintering contributes to greenhouse gases (GHG) (eg carbon dioxide) and is a source of SOx and NOx emissions. Coking capacity is also constrained by environmental concerns and economic factors, such as increased coke consumption, and short supply is leading to high prices. Improved coking practices, which result in reduced production of fines, are also contributing to the tight availability of breeze for sintering. This combination of factors presents an opportunity to consider alternatives to coke as a fuel for sintering. CSIRO Minerals has been investigating the use of wood biomass/char as a substitute for coke during sintering. Wood biomass, or char produced from it, is an attractive carbon source as carbon dioxide liberated during combustion can be sequestered back into growing biomass. It has great potential to reduce the emissions from integrated steelworks and improve their environmental acceptability. Harvested biomass/char is also a renewable and sustainable resource and can be integrated with good land management practices such as remediation of salinity affected land. Weeds, especially woody weeds, can also be used as a source of biomass for charcoal, and integrating char production with weed management can help address a pressing environmental issue in Australia. Previous reported preliminary testwork indicated that the use of Red Gum char as a replacement for coke resulted in a product sinter of comparable quality, improvements in productivity and significant reductions in SOx and NOx emissions. In the latest testwork, CSIRO has examined the properties of a range of potential charcoals, and has conducted a further series of granulation and small-scale sintering trials with them in simulated Japanese Steel Mill iron ore blends. Sinter fuels characterised and evaluated include industry sourced coke breeze, commercially available wood char and a charcoal from prickly acacia (acacia nilotica). Prickly acacia has been declared a noxious weed, is widespread in Australia, and is classified as a æWeed of National SignificanceÆ. The results presented in this paper support the notion that charcoal outperforms coke in many aspects of iron ore sintering and factoring in environmental considerations makes the switch to charcoal even more favourable.

Jan 1, 2005

By Shawn T. Sorrell, Carl Hrovatic

Land is a precious resource and should be treated as such by all members of our society. The soil covering this earth is only a very thin outer layer, varying in thickness from a few inches to a few feet and covering the rocks and minerals lying beneath the surface. The wise use of this valuable commodity is the responsibility of everyone. Many everyday activities disturb the earth's surface. Examples are highway construction, housing and commercial developments, agriculture, and surface mining. This chapter discusses the relationships of the environment to land as it applies to surface operations ill the coal industry. Mining by surface methods disturbs, for a brief period of time, thousands of acres of land annually. In addition, refuse piles, slurry ponds. abandoned mine structures, unprotected mine openings, and unsightly cleaning plants can also adversely affect land unless properly handled. ACTIVE SURFACE MINING OPERATIONS Mining by surface methods includes rock quarries; sand and gravel pits; huge open pits to extract iron, copper, phosphate, and other ores: and coal mining. Production of coal by surface methods is now approaching 300 million tons annually, amounting to almost 50% of the total coal output. Surface coal mining can be classified into the following four broad categories: Open pit mining is practised where the coal beds are extremely thick, as in some western states, or where the coal beds are sharply pitching, as in the anthracite region of the eastern United States. A typical open pit mine, with coal beds of 10 to 100 ft or more thickness and a relatively small ratio of overburden, generally employs large scraper-loaders to re-

Jan 1, 1973

By E. M. Elkin, J. H. Schloen

All known methods of treating and recovering the various components of copper refinery slimes are discussed. The slimes treatment processes presently used by five copper refineries are described and flowsheets are given. A bibliography is appended. THE recent increase in anode copper production at the Noranda smelter placed an additional load on the Montreal East plant of Canadian Copper Refiners Limited. The consequent increase in the amount of anode slimes led to a careful consideration of the various methods of slimes treatment. A critical review of these methods is presented here in the belief that it would be of interest to copper refiners. No such review has yet been published, although a number of individual flowsheets have been described. To make the information of greater value, a questionnaire was sent to all copper refineries. While the overall response to the questionnaire was not entirely satisfactory, the foreign refiners gave much detail in their answers and expressed willingness to cooperate further if needed. Although the data below do not cover all refineries, it is thought that examples of all flowsheets currently in use are included. A comparison of these flowsheets should prove of interest. The paper is divided into two parts. One part deals with a discussion of all known methods of treating and recovering the various components of the slimes. The second describes the processes now in use at various copper refineries for the treatment of raw slimes up to the production of Doré bullion. A brief description of the two main electrolytic methods of parting Doré bullion is appended. Since the first commercial application of electrolytic refining of copper by J. B. Elkington in 1865, the treatment of anode mud or slimes has undergone many changes. The object of treating slimes has always been the recovery and separation of precious metals. With the passage of time, increasing attention has been paid to improvement in recovery and quality of byproducts, mainly selenium and tellurium. The original methods of treatment were crude, although relatively direct. For example," the slimes were fused on a dolomitic clay bed in a reverbera-tory furnace; the slag was removed and the resulting metal cupelled to silver and gold. In another process, the dried slimes were oxidized and scorified on the lead bath of a cupelling furnace. Later, these pyrometallurgical methods were modified by sulphuric acid leaching, followed by fusion with niter in a reverb eratory furnace. A preliminary oxidizing roast improved the leaching step. Straight hydro-metallurgy has not found practical application. No matter what method is employed, the result is Dorb metal—a silver-gold alloy, with or without the metals of the platinum group. Characteristics of the Slimes Anode slimes are made up of those components of the anodes which are not soluble in the electrolyte. They contain varying quantities of copper, silver, gold, sulphur, selenium, tellurium, lead, arsenic, antimony, nickel, iron, silica, etc. The color of raw slimes is grayish black and the particle size is —200 mesh. However, Baraboshkin and Gaev (Ref. 1, p. 37), describe light gray colored slimes from the electrolysis of secondary copper which are composed predominantly of sulphates and of basic salts. In anode furnace practice primary and secondary metals are not usually segregated and such slimes do not commonly occur. Copper in the slimes originates to a large extent in the cuprous oxide of the anodes and is therefore dependent on the oxygen content of the latter: Cu2O + H2SO4 + CuSO4 + H2O + Cu [I] Opinions have been expressed that some of the copper is formed by decomposition of cuprous to cupric sulphate Cu2SO4 ? CuSO4 + Cu PI The product of either reaction is very finely divided. Depending on the slimes composition, much of the copper is combined with sulphur, selenium, tellurium, etc. The balance of the copper is in the free metallic state.

Jan 1, 1951

By R. A. Halatchev

Historically two basic approaches of production sequencing have been formed in the theory of open pit mine design. The first approach implements a technological discretization of the pit space within the ultimate pit outlines where the minimum working width is the limiting technological factor. The second approach uses a pseudo-economic discretization based on the implementation of analytical methods for designing intermediate/ultimate pit outlines and the concept of pit shells generation. The paper offers an elaborate analysis of both approaches used currently for discretization of the geological medium into working benches and modelling the working zone of open pit mine. The analysis is extended with a new vision for unification of the mining systems in open pit mine design under the form of a classification. A comparison of the approaches is provided to illustrate their advantages and disadvantages with regard to the implementation of the principle of waste deferment as one of the main principles of mine planning that exploits the time effect of money.

Jan 1, 2003

By Forrest T. Moyer

Injury experience in the mineral mining and processing industries during 1968 was slightly improved in the nonfatal-injury record but worse in the fatality record. The resulting frequency rate of all injuries was slightly better, whereas the injury-severity rate retrogressed appreciably from the figure for 1967. Overall operating activity, as measured by man-hours of worktime, was slightly higher in 1968. However, there were several major segments of the mineral industries in which activity was lower owing to reduced demand for mineral products and to several major work stoppages. These statistics comprise the injury and work experience of all personnel engaged in production, exploration, development, maintenance, repair, and force-account construction work, including supervisory and technical personnel, and working partners and owners at mineral-producing and mineral-processing establishments in the United States. Data concerning officeworkers are excluded except for the oil and gas industry for which such information is not separable. All injury rates and totals are calculated from data before rounding. The data for 1968 are preliminary except for the anthracite, coke, petroleum and natural gas, native asphalt, peat, and slag industries, which are final. The figures represent full coverage for all industries except oil and gas for which coverage is not complete, particularly with respect to small companies.

Jan 1, 1970

The main goal of this paper is to present readers with recommendations for choosing coaxial cables appropriate for mining applications of Time Domain Ref 1 ectometry (TDR) to monitor rock mass movements. Prior to discussing the recommendations, mining applications are illustrated with examples and the operating principle of TDR is discussed briefly. Items that affect the result of the monitoring system performance include the coaxial cable selected, the grouting material used, and the installation procedure.

Jan 1, 1986

By Jesús Londoña

La presente investigación se llevó a cabo en una planta de lixiviación de oro donde se trabaja con el cianuro de sodio, el cual es desprendido en forma de gas en las diferentes etapas del proceso , realizándose las mediciones respectivas y registrando que la mayor volatilización del gas cianhídrico (HCN) se lleva a cabo en la relavera; por lo que se hizo el análisis de diferentes parámetros como: cianuro libre, pH y temperatura, con las pruebas a nivel laboratorio e industrial se logró disminuir la volatilización y el impacto al ambiente del gas cianhídrico HCN en la relavera.

Sep 1, 2017

By C. P. Walker

Determining the distance to remote objects by observing the time required for sound to traverse the intervening space is an old practice. Attempts have been made to use this method for determining the fluid level in oil wells but as far as the writer is aware it was not found to be practicable, because vibrations in gas in the audible frequency range do not travel as well and as far as low-frequency pressure waves, which are capable of transmitting a greater amount of energy than can be transmitted by audible waves. Wood, in his book "Sound," states that in a given medium the range of sound transmission will vary inversely as the square of the frequency. The fact that the sound from a whistle having a low tone has a much lower attenuation rate than that from a whistle of high pitch is well known. Also, the pressure waves caused by cannon fire often rattle windows at points so distant that no sound of the cannon is heard. In 1932 P. E. Lehr and H. T. Wyatt, of the Shell Oil Co., experimented with the principle of the concussion, or pressure-wave echo, method of determining fluid levels in oil wells. They released compressed gas into the top of the casing, thereby creating a pressure wave, which traveled down the well and back again. Their experiments proved conclusively that, with the proper apparatus for recording the echoes and determining the velocities at which the waves travel, the method could be used successfully for determining fluid levels in oil wells. Wells are often equipped with from one to three tubing catchers and these together with the top of the liner are frequently above the fluid. Each of these obstructions reflects a part of the pressure wave. In such wells there may be, therefore, as many as five pressure-wave reflections. Thus it is obvious that in order to identify the various reflections and to determine therefrom the fluid level in a well it is necessary to obtain a graphic record of these reflections.

Jan 1, 1937

By Robert C. Speck

Floor heave or deformation of the mine floor into the mine opening is a problem which has plagued coal mines in this country and others. In mining areas where room and pillar mining is practiced, floor heave generally occurs when the stress applied to the floor material by a coal pillar exceeds the bearing capacity of the floor strata. When the floor strata beneath the coal pillar fail, the pillar moves downward and displaces the material under it. This material, in turn, moves outward and upward into the mine opening (Figure 1). As the underlying materials fail, the load supported by the coal pillar may be transferred to adjacent pillars. If these are marginally stable, they too may become overloaded and push into the floor. Thus, floor heave can spread through a large portion of the mine in a progressive manner. As the pillars push into the floor, differential movement and flexure of the roof strata may cause them to weaken and fail, resulting in subsidence of the ground surface above the mine. This paper describes the problem as it was manifested in the Zeigler Coal Company No. 5 and Murdock room and pillar coal mines near Murdock, Illinois, and reports the results of a U. S. Bureau of Mines- sponsored study conducted by the University of Missouri-Rolla. During the course of the study, floor heave in the two mines hindered the transportation of men, machines, and coal to and from the working mine-face, interrupted ventilation plans, drastically increased roadway maintenance costs, intensified safety and strata control problems, destroyed large pieces of equipment, and, several times, pre- vented access to otherwise minable coal resources. The ultimate objective of the study was to develop one or more simple procedures to allow detection of a potential floor heave problem during the exploration phase of mine design--before initiation of production mining.

Jan 1, 1981

A paper describing the treatment of the Mary Kathleen uranium ores must necessarily be historical and confined mainly to a review of the four papers which have already appeared. Couche and Hartley (1958) described the development of the treatment process just prior to the commencement of operations in June, 1958. Harris, Boag and Hemingway (1961) described the treatment during the operations, and Wreford (1965) reviewed all aspects of the mine and mill, when operations were suspended in November, 1963. Harris and Steele ('1960 presented a paper especially describing the radiometric sorting operation. Some hitherto unpublished information is also presented in the paper to describe some of the peculiarities of the ore, indicate reasons for the adoption of the treatment flowsheet, and some interesting problems connected with this treatment.

Jan 1, 1968

By Stephan Stecura

Crystallographic modifications and kinetics of solid-state phase trans-formations were determined for five rare-earth" sesquioxides--La2O3, Nd2O3, Sm2O3, Eu2O3, and Gd2O3. Oxides used for crystal modification studies were prepared by thermal decomposition of the following high-purity salts of the five rare-earth elements--carbonates, chlorides, fluorides, nitrates, oxalates, and sulfates. X-ray diffraction patterns of the cubic and hexagonal oxides were indexed by a graphical method and patterns of the monoclinic oxides by Ito's method. The kinetics of crystallographic transformation were determined by high-temperature X-ray diffractometry. The kinetic data were interpreted using a shrinking sphere model. All of the transformations followed first order kinetics. Activation energies were calculated by application of the Arrhenius equation. These solid-state phase inversions were concluded to occur by a reconstructive transformation mechanism.

Jan 1, 1965

By Carl Davis

A description is given of grinding practice on the Rand and of experiments made to improve that practice. The paper includes a description of the experimental plants and methods and the results obtained. THE first tube-mill on the Rand was put into operation in May, 1904, at the Glen Deep Mine. From that time onwards, tube-mills were added to various plants, although little was known regarding the capacity of a given tube-mill when working on banket ore. Within a few years, however, the so-called standard size (length of shell 22 ft. 0 in. diameter 5 ft. 6 in.) was generally used until the last year or two. Practically the only exceptions were about 30 tube-mills having a length of 16 ft. and a diameter of 6 ft., and a few open-end mills of the roller-supported type. Most of the information obtained during the last 15 years has been obtained with mills of the standard dimensions. The adoption of the tube-mill as an accessory to the stamp mill was rapid; and where 3 tube-mills were working on the Rand at the end of 1904, 244 were in use seven years later.1 By 1910, good practice provided 1 tube-mill for 20 stamps of 2000-lb. falling weight. The horsepower of the motors driving the tube-mills had increased from. 80 to 100 and then to 125 at this date. Broadly speaking, current practice at that date aimed at a final product of which 60 per cent. was suitable for sand treatment and 40 per cent. for slime. The sand grading was +60 mesh, 6 per cent.; +90 mesh, 25 per cent.; -90 mesh, 69 per cent.; and the slime grading -200 mesh, 2 per cent.; -200 mesh, 98 per cent.

Jan 12, 1924

By John D. Watson

The results of extensive field tests of a new and powerful method of hard rock excavation are presented in this report.* The method, known by the acronym REAM (Rapid Excavation and Mining), employs high velocity, smooth bore cannons to efficiently deliver energy to the rock and has been demonstrated for underground tunneling, drilling, surface benching, scaling, and secondary breakage in hard granitic rock at the Hope Valley Mine test site in California. Solid projectiles made from inexpensive materials such as concrete or steel, and weighing from 8 to 12 pounds, are launched by conventional high speed cannons and impact the rock at velocities of 5000 feet per second--an impact energy of about 4 million foot pounds (Figure 1). The energy applied at peak pressures of nearly 2 million psi over a period of tens of microseconds breaks down the rock by a complex mechanism of crushing, spalling, and initiation and propagation of fractures produced by the interaction of successive impacts and free surfaces. The main objective of the tests during 1973 was a demonstration of controllability of the underground operation of a silenced cannon. To accomplish this objective a 90-mm cannon

Jan 1, 1974

The Olympic Dam Mining Operation involves the supply of some 2.2 million tonnes per annum of ore feed for the metallurgical plant. To achieve this approximately 9 km of tunnels are developed per year to gain access to the long hole open stopes that supply the majority of the production tonnes.Vast amounts of data are produced in the mining activity from the geology, mine design, scheduling, surveying, shift reporting through to the statistical reporting and analysis of the performance of the mine activities. Care must be taken when obtaining the data to maximise the usefulness of the data to other users so not to impose constraints or additional processes on future users.

Jan 1, 1992

By Augustus Locke

THE technical sessions at the Regional Meeting of the A.I.M.E. in San Francisco are to be de- voted LO changes, current or predictable, which may be expected to alter today's practices in mining and metallurgical engineering. Our present condition may be summarized as follows: Capacity to produce is excessive for domestic needs in molybdenum, copper, iron, and oil; sufficient in lead, zinc, and potash; deficient in aluminum, manganese, tungsten, chromium, and tin. Gold and silver are complicated by their use as money. Or, to look at it in another way, the "growth curles" of production, as C. K. Leith emphasizes, characteristically rise slowly at the beginning, show a second stage of rapid growth, and a third stage of leveling off. The third stage is already reached here in coal. copper, iron, lead, and zinc. But still in the second slage are oil, molybdenum, potash, and others.

Jan 1, 1939

By V. R. Degner

The trend in both the metallic and non-metallic mining industry is toward processing increasing y higher tonnages of lower grade ores, thereby resulting in a growing interest in progressively larger volume individual machines in the flotation circuit. Because of the relatively high cost of large flotation machine development and evaluation, it is important to establish a rational basis by which the existing smaller flotation machine experience can be extrapolated to establish the configuration of the next larger family of flotation machines with a minimum of development modification in the field. This paper reviews the R&D approach used in translating smaller flotation machine experience to establish the configuration of a 1000 cu ft (2B.3 cu m) induced air machine. Internal cell hydrodynamic principles, which governed this extrapolation, and cell (liquid) surface and froth management considerations will be reviewed, and prototype machine mill tests will be summarized.

Jan 1, 1978

By Greaves J. N

The U.S. Department of Interior, Bureau of Mines, is investigating the treatment of refractory gold ores. Chlorination in the treatment of refractory gold ores is applicable in many low-grade gold operations. When usable, this treatment provides an economic means of consuming sulfides and deactivating disseminated organic carbon. Chlorination, however, is a pretreatment technique that requires the neutralization of the chlorine prior to leaching the ore with cyanide. Research by the Bureau has extended the present chlorination technology to allow for the recovery of gold without the use of cyanide and allow treatment of some ores presently deemed untreatable by gold operators using cyanidation or chlorination/cyanidation techniques. Chlorination without carbon of two carbonaceous ores extracted between 1 and 20 pct of the gold; however, carbon-in-chlorine (CICL) treatments resulted in about 90-pct recovery with a reduction in carbon loading. A statistical design campaign for stripping metallic gold from the carbon loaded in a chlorine environment demonstrated elutions exceeding 90 pct.

Jan 1, 1991