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By J. S. Redpath

There appears to a definite trend toward the hoisting of greater tonnages from greater depths. There is every indication that this trend will continue and we feel that improvements in the design, fabrication and installation of mine guides will be of significant importance in the future. The present state of the art in mine-shaft guide systems is reviewed and the parameters required for improvement are derived in this paper. Finally, a proposal is made for a new steel guide system which meets the parameters and is economical to fabricate and install.

Jan 1, 1977

By A. F. Edwards

The Main Pass sulphur and oil deposit is located at Main Pass Block 299 in the Gulf of Mexico, 30 miles east of Venice, Louisiana, in 210 feet of water. The deposit was discovered by Freeport-McMoRan and its joint venture partners, IMC Fertilizer and Homestake Mining, in late 1988-early 1989. The sulphur deposit contains 67 million long tons of recoverable sulphur. The sulphur occurs in bio-epigenetic limestone replacing anhydrite caprock on top of a salt diapir. Recoverable reserves of 39.4 million barrels of oil and 9.1 billion cubic feet of gas are also contained in the limestone caprock and in supracap sandstone stringers.

Jan 1, 1992

By F. Sill

The disposal of residual material from processing and combustion of coal, from incineration of domestic refuse and sewage sludges kind to the environment is a prior task for the future. Deutsche Montan Technologie (DMT) has developed a new technique which makes possible to fill-up goaf cavities behind running caving systems in coalmining. In a mixing and pumping station on the surface high concentrated suspensions are produced from the above mentioned materials. The paste is pumped through pipes to the coalfaces and via trailing discharge pipes stretched to the fracture zone in the caved-in goaf. Since three years a special designed plant is working successfully on a coal mine of Ruhrkohie AG.

Jan 1, 1994

By P. M. Cole

An unprecedented expansion of the global zinc industry is currently under way. While most new projects and plant upgrades remain committed to traditional processing technologies, recent advances in zinc solvent extraction (SX) have created opportunities for new process routes for both primary and secondary materials. The first commercial plant to use zinc SX for the mainstream processing of a low-grade ore is under construction and promises to become one of the lowest cost zinc producers. Several other oxide and sulphide projects in various stages of feasibility are considering the inclusion of SX in their process flowsheet. Zinc SX has also proved advantageous in the reprocessing of secondary materials, particularly for the treatment of zinc residues and furnace dusts. This review focuses on recent installations and projects underdevelopment that feature zinc SZ as the key separation step.

Jan 1, 2002

By G. F. Kuncir

The analysis summarized herein evaluates the Bureau of Mines Program for Advancing Mining Technology Oil Shale in terms of the economic benefits which may be derived for the Nation as a result of its successful research and development efforts. On the basis of postulated oil shale production scenarios, benefit-cost ratio indicators are computed for the program elements as they apply to surface, underground, and modified in situ oil shale mining systems. Eight value indicators are used to measure the Program's beneficial impact on the future oil shale industry in relation to planned research and development costs. These are: capital cost savings, operating cost savings, labor savings, environmental quality maintenance cost reduction, reduction in production costs, byproduct production benefits, total production benefits, and additions to recoverable reserves. Program costs are aggregated from 1974 through 1987 and major benefits are accrued from 1982 through 2040. Both cost and benefit streams are discounted to mid-1975 present value.

Jan 1, 1977

Until recently, nickel laterite projects have been largely ignored, due to their supposedly higher treatment costs compared with sulphides, and to their perceived processing difficulties. A number of laterite projects in the 1970s were abandoned because of high capital and operating costs, while others experienced severe technical difficulties. Conventional wisdom had it that laterites would not be exploited until most of the sulphide orebodies had been depleted. Why then, have Australian mining and exploration companies started a resurgence of interest in the treatment of nickel laterites? It all began with the Bulong project, which has been under study since 1987, while more recently two further projects, Murrin Murrin and Cawse, have been initiated and are being fast-tracked to take advantage of the current high nickel and cobalt prices. A further project in NSW, Syerston, has also been investigated at bench-scale, but no further development has yet been announced. All these projects have the following advantages: 1. Good location near a major mining centre and,reasonably close to power, water, roads, accommodation and a developed service industry. 2. Straightforward, low cost mining. 3. Low cost of acid or sulphur. 4. Good to very good cobalt credits. In addition, there have been significant technological developments in the design and operation of high pressure autoclaves and high rate thickeners, as well as solvent extraction and electrowinning technology. This has helped to decrease capital costs and technical risks, and has allowed the development of alternative flowsheets to the existing laterite operations (Taylor, 1996).

Jan 1, 1996

By D. Harry Chambers

The Bureau of Mines, through a memorandum of agreement with the Department of Defense, conducted research to recover silver from aircraft scrap. Silver was recovered by an electrolytic method from stainless steel honeycomb sections separated from the aircraft. These sections had been constructed by sandwiching a stainless steel honeycomb core between stainless steel sheets and then brazing the assembly with a silver alloy. Over 300 pounds of silver was used in the B-58 bomber, concentrated in certain honeycomb sections of the aircraft. Following shredding of the aircraft parts, an average of 95 percent (ranging 67 to 100 percent) of the silver was recovered in a single electro-refining step. After the electrorefined product was magnetically cleaned, purity of the recovered silver was greater than 99.3 percent.

Jan 1, 1980

There is a significant amount of historical mining and exploration information available. This information is often distributed throughout a number of reports or plans, available from a variety of sources, and in many differing formats. The ability to capture paper-based historical information in a modem digital format provides mining and exploration companies with valuable information that can be used in a number of ways; for example, reassessments of exploration or mining work previously undertaken, or used in conjunction with current exploration information.   The purpose of this paper is threefold. Firstly, to present the paper-based historical information; highlighting some of the problems encountered, solutions to those problems, and any assumptions used. Secondly, to present the historical data in digital format, and demonstrate the tools available to analyse geological and associated information, and finally, to illustrate some of the potential future applications of the information, including mining optimisation, mine design and scheduling.   The Glenorchy scheelite/gold prospect has been used as an example. Within the overall prospect two smaller areas were selected. The Mount McIntosh and surrounding areas, focuses on exploration and surface excavation information. The Mount Judah area (State and Kelly-Taylor workings) focuses on underground mining and exploration information.  

Jan 1, 2001

By J. H. E. Jeffes, C. Diaz

The heat balance and chemical equilibria involved in the production of blister copper from a chalcopyrite concentrate in a single operation are examined. It appears that two stages—one oxidising and one reducing—will be required. The analysis indicates that on thermal grounds the process is possible with a dry, high-grade chalcopyrite concentrate, if oxygen enrichment to about 30 per cent is used, but that copper losses in the slag will be serious and will require a secondary recovery operation. More extensive data on the activities of copper oxide in slags are required to elucidate this point more effectively

Dec 1, 1971

8053. Andreev, B. A. Zakashanakii, M. S., Samsonov, N. N., and Fotiadi, E. E. A Textbook of Gravitational -Surveying, (in Russian). Gosgeolizdat, Moscow-Leningrad, 1941, 432 pp. This textbook was written at the suggestion of-the faculty of geophysical exploration of the Leningrad Mining Institute. It contains two parts: (1) Theory and technique, and (2) Applications to geology and exploration. The features bringing; the text up-to-date include: (a) Description of the principal modern gravimeters; particular attention to the method of simultaneous oscillation of 4 pendulums; (b) discussion of the aperiodic oscillation of torsion balances; outline of the construction of variometers Z -20 and Z-40; (c) material for aid in interpretation, such as reference-charts, formulas with their derivation, atlas of theoretical curves, and examples of interpretative calculations; (d) considerations in the planning of surveys and the densities of various rocks; and (e) detailed analysis of significant examples. The text is provided with a bibliography, V. S.

Jan 1, 1946

By Warren G. Burres

or more than 50 years the Portland Cement Association has represented the United States cement industry in matters relating to the technology and use of cement and concrete. Interestingly enough, PCA?s emphasis has been on concrete and its uses rather than on Portland cement. The cement industry realized long ago that cement is basic and serves its fundamental purpose as an ingredient in concrete. Cement could never be successful if concrete were not. Work with the users and specifiers of concrete had to be done at its end point of application--in a building, bridge, dam, highway or home. PCA, over its half century of existence, has been dedicated to this job. I should like to talk to you today on the less technical side of concrete--what it has been--what it is today--and what it can offer in future construction. Concrete, in many forms, has a long background extending from such notable historic times as the Roman Empire. Here, concrete made from pozzolanic cement from the slopes of Mt. Vesuvius was used to construct the Coliseum, home of the Roman circus; for the Appian Way, the ancient forerunner of the Interstate system; and the miles of aqueducts throughout Europe, many of which still carry water. In 1811 Joseph Asppin, an English bricklayer, made the first modern cement by the artificial mixing of pulverized limestone and clay materials. Ht,

Jan 1, 1971

By W. P. Diamond, J. R. Levine

The explosion hazard of methane-air mixtures has become an increasingly serious mine planning problem, and an advance assessment of methane gas potential can therefore be essential for a safe and economic mine development pro- gram. As part of its coal mine health and safety program, the Bureau of Mines has developed a simple, inexpensive test to measure the methane content of coal samples obtained from exploration cores. The gas content of coal per unit weight as determined by the direct method test can be used as a basis for a preliminary estimate of mine ventilation requirements, and to determine if degasification of the coalbed in advance of mining should be considered. Since the Bureau began measuring the gas content of coal samples in 1972, experience has led to equipment and procedural changes, the most significant of which has been the development of a ball mill for crushing the coal sample to release the residual gas at the end of the desorption test period. This revised procedure replaces the crushing box and graphical methods described in earlier Bureau publications. The results of 583 direct method tests are summarized in tabular form. These results include data on the gas content of 125 coalbeds in 15 States.

Jan 1, 1980

By Jan Petter Maehlen

Solid H-absorbing materials are in focus of ongoing R&D to offer viable solutions for the hydrogen storage and supply systems aimed on use of hydrogen as energy carrier for automotive transportation. Low operating pressures, combined with high gravimetric and volumetric efficiencies, together with fast kinetics of hydrogen release at ambient temperatures (providing conditions for a low energy loss due to decomposition), are the most important features of the ?ideal? H storage material. Hydrides of the light elements are the only possible candidates to build systems with an overall efficiency similar to those accommodating liquid or compressed (700 bar) hydrogen. One promising material from this point of view is aluminium trihydride, alane AlH3 with a gravimetric storage capacity of 10 wt.% H. This work was focused on studies of the crystal structure and thermal decomposition of alane by application of powder synchrotron X-Ray diffraction.

Jan 1, 2006

By G. R. Hopkins

According to reports as of January 1, 1931, the total daily charging capacity of the cracking plants, hoth completed and under construction, in the United States amounted to 1,950,781 "barrels, an increase over the previous year of 14 per cent. The total daily capacity of the operating plants amounted to 1,594,990 "barrels, or 82 per cent of the grand total, the capacity of the in¬ operative plants was 244,661 "barrels, or 12 per cent of the total, while the capacity of the plants under construction amounted to 111,130 "barrels, or 6 per cent. In comparison with a year ago, these data indicate a decline in the total capacity of the plants "being "built "but show material increases in the capacity of "both the other two classes. The increase in total inoperative capacity and the decline in construction in 1930 undoubtedly resulted from un¬ satisfactory economic conditions. The total number of cracking units completed or under construction on January 1, 1931, totaled 1,863 as compared with 2,002 the previous year and with a high of 2,559 on June 1, 1926. During the period between June 1, 1926, and January 1, 1931, the total charging capacity of the cracking plants has more than doubled, but the number of units has shown a material decline. This condi¬ tion has been brought about largely through the dismantling of many Burton still of small capacity and through the tendency to increase the size of the new units The "largest unit that can be identified in this survey has a daily charging capacity of 10,000 barrels, but undoubtedly there are some that would exceed this in size. Texas, with a total of 575,300 barrels, ranked far ahead of the other States in charging capacity, and was followed in order by California, Indiana, Oklahoma, and Pennsylvania. Indiana, with only five refineries, ranked third in cracking capacity, which illustrates the importance of the Chicago district as a gasoline-producing center. Not all of the States showed a gain in capacity during the year; in fact, four of them, namely Illinois, Louisiana, New York, and Oklahoma, reported a decline.

Jun 1, 1931

By Gordon M. Matheson

The factors which control chimney subsidence sinkhole development in weak rock were assessed by analyzing the characteristics of approximately 3000 chimney subsidence features along the Colorado Front Range. The area of study included features developed over abandoned mines in the Colorado Springs Coal Field, the Boulder Coal Field, and the Foothills District. The approximate locations of the areas studied are shown in Figure 1. Data were collected for sinkholes occurring over both room and pillar, and retreat mining areas in coal seams with a wide range of dips. The location, size, and approximate time of development of each sinkhole were documented. From these data, relationships were developed which describe the time rate of observable sinkhole development and the relative location of sinkhole development with respect to mined height, overburden thickness, and type of mining for relatively flat-lying coal seams. In addition, the observed locations of sinkhole development over steeply dipping coal seams were assessed for portions of the study area.

Jan 1, 1986

By Robert N. Morris

Ladies and Gentlemen: It is a distinct pleasure and honor to appear before you representing the railway industry as I do, but there is a much closer personal relationship. I am a graduate Mining Engineer and worked in the coal industry for 15 years prior to becoming a railroader only 4 ½ years ago. I have been a member of AIME most of my adult working life and am currently active in the Washington, D. C. Section. While having been in the railway industry only a short time, I have become involved during the recent period of innovation and development of the new railroad technique known as unit train service. I have had the privilege of helping to work out a number of unit train movements to both electric utility companies and to a major steel concern, handling coal from mines on the Southern Railway to the consuming plants. On Southern, our unit trains are all of what I shall describe as shuttle train operations whereas within the railroad industry today several types of service are characterized as unit train service and many don't offer comparable efficiencies.

Jan 1, 1968

By Phillip N. Yasnowsky

This Bureau of Mines report summarizes State severance taxes imposed on minerals and mineral fuels, provides a hypothetical example of how a State severance tax affects selected components of a firm's income statement, and uses the Bureau's Minerals Availability System (MAS) to estimate the effect of assumed changes in State severance tax rates on copper recovery cost at given levels of potential copper availability. A reduction of the rates to zero or a doubling of them results in changes in costs that are of the same order of magnitude as the cost of transporting copper to the United States from major foreign producing countries.

Jan 1, 1982

By J. Groppo, W. Zhang, R. Honaker

"Rare earth elements (REEs) found in coal are in the form of minerals, ion-adsorbed onto clay surfaces or inner layers, or organically bound. Rare earth minerals such as monazite exist in coal and have grain sizes smaller than 5 µm. In this study, froth flotation was successful in concentrating rare earth minerals existing in a thickener underflow material derived from Fire Clay seam coal that contained around 431 ppm of total rare earth elements (TREE) on a dry ash basis. Conditioning with fatty acid followed by processing using multiple stages of conventional flotation produced a final concentrate containing 2,300 ppm TREE. Using a laboratory flotation column to limit hydraulic entrainment, the TREE content was further enriched to around 4,700 ppm, which equated to an enrichment ratio of 10:1.IntroductionRare earth elements (REEs) are becoming increasingly important and have been widely used as raw materials for the production of phosphor, metal catalysts, magnets and batteries (Binnemans et al., 2013; Zhang et al., 2015). REE recovery from alternative sources such as coal and coal byproducts has the potential to stabilize the economic viability of coal mining operations while providing a dependable supply of critical materials.The average REE content of the world’s coal resources is around 60 to 70 ppm (Zhang et al., 2015). There are many well-known coal beds with high contents of REEs such as those in the Far East coalfields in Russia with contents of 300 to 1,000 ppm, the Fire Clay coal seam in eastern Kentucky in the United States with contents around 500 ppm and the Sydney Basin in Nova Scotia, Canada, with contents of 72 to 483 ppm (Birk and White, 1991; Seredin, 1996; Hower, Ruppert and Eble, 1999; Blissett, Smalley and Rowson, 2014). The occurrence of REEs in coal and coal byproducts can be classified into three types: (1) rare earth minerals, such as monazite and xenotime, (2) ion-adsorbed REEs on clays and (3) REEs associated with organic matrices. The rare earth minerals in coal and coal byproducts are very small in particle size, generally on the micrometer and/or nanometer scales (Honaker et al., 2014). Froth flotation, which concentrates minerals based on surface chemistry differences, has been widely used to treat fine rare earth industrial minerals such as monazite, xenotime and bastnaesite (Abeidu, 1972; Cheng, Holtham and Tran, 1993; Pavez and Peres, 1994; Pavez, Brandao and Peres, 1996; Jordens et al., 2014). As such, flotation is a promising method for the concentration of rare earth minerals from coal and coal byproducts."

Jan 1, 2017

By A. Rios

ENAMl's Paipote Smelter commenced operations in 1951. At present, it processes 230,000 tonnes/year of green feed in a conventional smelter, which comprises one reverberatory furnace, two Hoboken, one Peirce-Smith converters and one rotary anode furnace. The feed is composed of 83% copper concentrate and 17% metallic copper precipitates, which results in a feed average grade of 32% of copper content. The final products are 75,000 tonnes/year of copper anodes and 48,000 tonnes/year of sulphuric acid. At present, the plant is undergoing a modernization to expand the smelter capacity to 300,000 tonnes/year of green feed and increase the sulphuric acid production to 100,000 tonnes/year. This will be achieved with the installation of an El Teniente Converter and an expansion in the acid plant. The work began in November 1991 and is scheduled to be in operaton by March 1993. The paper provides an overview of the modernization plans and results achieved to-date.

Jan 1, 1993

By J. Glazewski

The mining industry in South Africa has developed its own environmental guidelines in the form of an Aide-Mémoire1,which is an extension of the previous rehabilitation provisions to include all aspects of the environment and all phases of a mining operation. This development, at the time, recognized an international trend towards the formalization of environmental management in mining practice, which resulted from the realization of the large environmental liabilities that mines could face, particularly on closure. Over the past decade the international environmental focus in the mining industry has moved from operational management, to the reduction of liability on mine closure. Mine closure guidelines are being developed internationally by nations (for example, SRK, 19982) and by large mining groups (for example, Rio Tinto, 19983). In South Africa the Department of Minerals and Energy (DME) is presently reviewing the Aide-Mémoire to bring it in line with international and local developments and a separate mine closure plan is being considered.

Jan 1, 2000