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The Tuesday morning session opened at 9:00 a.m. and was presided over by Mr. Homer Hyatt, Safety Director, North American Coal Corporation, Western Division, Castle Gate, Utah. Mr. Hyatt introduced Mr. Richard F. Walker, Vice President, Engineer & Planning, Electric Department, Public Service Company of Colorado, Denver, Colorado. Mr. Walker is a native of the State of Nebraska, a graduate of the University of Colorado with a BSEE degree in 1949. He has been associated with the Public Service Company of Colorado for almost twenty years and in the above capacity for the last one and one-half years. Mr. Walker?s subject was "Our New Plants and Coal. (See index for printed text of Mr. Walker's paper.) Mr. John F. O'Leary, Director, U.S. Bureau of Mines, Washington, D. C. spoke on the ?High Cost of Economy.? Mr. O'Leary graduated from George Washington University in 1950 with a degree in Economics. In 1950, he joined the Bureau of Mines. In 1963 he was appointed Deputy Assistant Secretary, Mineral Resources, U.S. Department of the Interior. In 1967, he was appointed Chief, Bureau of Natural Gas, Federal Power Commission. In 1968, appointed Director, U.S. Bureau of Mines, Washington, D.C.

Jan 1, 1969

Projects to be undertaken in remote locations require special attention with regard to constructability from the very first stages of design. This is to ensure not only that the project is compatible with the environment in which it' is proposed to be built, but that it does not require facilities or special construction equipment and expertise that is not available in the proposed location. This paper draws on experiences gained on projects in Alaska, Northern Canada, South East Asia, outback Australia, and more recently Bougainville, in Papua New Guinea, where over the past 5 years Minenco has undertaken in excess of A$120 million of work on a number of different projects for Bougainville Copper Limited Although many of these projects have been close to large populous cities, which have been served by regular shipping and airline services, the locations have not had the availability of construction facilities which exist in major cities of Australia and thus can only be considered as remote locations by current day standards. As a result, every nut bolt and washer has had to be brought to the job site by the construction company. No hardware or electrical warehouses existed for those forgotten half dozen high tensile bolts, spring

Jan 1, 1986

THE Institute assembled in the metallurgical lecture-room of Pardee Hall, Lafayette College, at 7 o'clock P.M. on Tuesday evening, October 21st. The session was opened by the President, R. W. Raymond, with an address on Mining Industry as illustrated at the Vienna Exposition. The second session was held on Wednesday morning. The Council reported the following names for election as members and associates. They were unanimously elected. †Ayres, W. S., - Easton, Pa. *Baker, Prof. A. L., - Easton, Pa. †Browne, Thomas Nicholl, - Hamilton, Nev. *Carter, Frank, - Pottsville, Pa. *Davis, E. F. C., - Pottsville, Pa. *Fox, Prof. J. G., - Easton, Pa. *Haight, Ogden, - Etna, Pa. †Hall, Norman, - Sharon, Pa. *Knap, Joseph, - Fountain Mill, Pa. †Miller William McKeen, - Easton, Pa. †Pardee, I. P., - Easton, Pa. *Plater, John E., - Eureka, Nev. *Platt, Joseph L., Jr., - Franklin Furnace, N. J. *Plumb, W. H., - Mauch Chunk, Pa. *Reis, George L., - New Castle, Pa. *Samuel, Edward, - Philadelphia, Pa. *Smith, William Allen, - Trenton, N. J. *Smock, Prof. John C., - New Brunswick, N. J. *Weberling, Charles, - Salt Lake City, Utah. Also the following as foreign members Beaulieu, Ad. le Hardy de, - Brussels, Belgium.. Beaumont, Major Fred., - London, England. Beck, Alexander, - Mons, Belgium. Bodmer, J. J., - London, England. Brassert, Berghauptmann, Dr., - Bonn, Prussia. Brogden, James, - London, England * Members. † Associates.

Jan 1, 1874

By B Hu, B Zhang, J Wang, H Ma, D Liu, L Han

Zeolites are potential carriers of slow release fertilisers due to their unique phenomenon for salt occlusion. A comparative study was performed on the capacities of potassium nitrate (KNO3) occlusion in molten KNO3 treated synthetic 4A and 13X zeolite molecular sieves with main channel sizes of 0.41 x 0.41 nm and 0.74 x 0.74 nm respectively. The results show that in a laboratory setting, the treated zeolite 4A contained 13.57 per cent of occluded KNO3 and the treated zeolite 13X did not contain any. This was confirmed by the regular release of K+ and NO3- during washing both treated mixed samples with water and by their IR spectra and TG analysis. There are also changes of the relative intensities of peaks in X-ray diffractograms of both treated zeolite samples. K+ release from molten-KNO3 treated zeolites in deionised water and simulated soil solution shows that release of K+ from KNO3 occluded in zeolite 4A are slow and steady. Proper size fit between the channel size of zeolites pore and the size of K+-NO3- ion pair of KNO3 is the decisive factor for zeolites to occlude KNO3.

Jan 1, 2008

The Institute assembled in the metallurgical lecture-room of Pardee Hall, Lafayette College, at 7 o'clock P.M. on Tuesday evening, October 21st. The session was opened by the President, R. W. Raymond, with an address on Mining Industry as illustrated at the Vienna Exposition. The second session was held on Wednesday morning. The Council reported the following names for election as members and associates. They were unanimously elected. Ayres, W. S.,.......Easton, Pa. *Baker, Prof. A. L.,.. Easton, PR. Browne, Thomas Nicholl,.... Hamilton, Nev. *Carter, Frank,......Pottsville, Pa. *Davis, E. F. C.,... Pottsville, Pa. *Fox, Prof. J. G.,...,..Easton, Pa. *Haight, Ogden,...Etna, Pa. Hall, Norman,...Sharon, Pa. *Knap, Joseph,......Fountain Mill, Pa. Miller William McKeen,.... Easton, Pa. Pardee, I. P.,....Easton, Pa. *Plater, John E.,......Eureka, Nev. *Platt, Joseph L., Jr.,.....Franklin Furnace, N. J. *Plumb, W. H.,......Mauch Chunk, Pa. *Reis, George L.,......New Castle, Pa. *Samuel, Edward,. ..Philadelphia, Pa. *Smith, William Allen,.....Trenton, N. J. *Smock, Prof. John C.,..... New Brunswick, N. J. *Weberling, Charles,.....Salt Lake City, Utah. Also the following as foreign members: Beaulieu, Ad. le Hardy de,. . Brussels, Belgium. Beaumont, Major Fred.,..London, England. Beck, Alexander,.Mons, Belgium. Bodmer, J. J.,..London, England. Brassert, Berghauptmann, Dr.,. .. Bonn, Prussia. Brogden, James,.London, England.

By A. J. Burger, F. L. D. Cloete

Tests indicated that effective recovery of pyrite from a coarse Witwatersrand quartzitic ore can be accomplished by intensified flotation in an air-sparged hydrocyclone. Air is fed through the porous cylindrical wall of the hydrocyclone into a swirling layer of slury. Hydrophobic particles are attached selectively to small air bubbles, which form a froth and are recovered through the overflow. Hydrophilic particles pass out in the underflow. A spigot in which flow is restricted by an orifice was found to be more successful in preventing blockage by wood chips than an annular opening between a pedestal and the cylinder wall. Pyrite recoveries of 85 to 93 per cent at grades of 35 to 40 per cent sulphur were obtained in the air-sparged hydroclone with residence times of about 1 second. Comparative tests in a batch flotation cell after 320 seconds yielded average recoveries of up to 96 per cent, but with a mean grade of 32,5 per cent sulphur. A high colector dosage of 120 g/t was required in the cyclone, compared with the 40 gft used in conventional operations. An air flowrate of about 150 I/min was adequate at a slury feed rate of 35l/min. Particle sizes between 38 and 106µm yielded the best flotation results.

Jan 1, 1988

By S. A. Ferguson

Purpose: Marras et al. developed a technique to evaluate sincerity of effort during dynamic trunk motion performance. The validity and reliability of the technique have not been evaluated. Therefore, the objective of this study was to first determine whether or not a sincerity of effort measure correctly identified those giving a sincere effort in a blinded randomized control trial and second to quantify inter-rater and test-retest reliability. Methods: This article reports the findings of a two phase study. In phase one, the blinded evaluation, participants were randomly assigned to either a sincere or insincere performance condition. An examiner tested participants without knowledge of the participant's group membership. In the second phase, two examiners evaluated each participant twice to quantify inter-rater and test-retest reliability. Results: In the blinded phase the specificity was 100% and sensitivity was 90% for identifying sincere and insincere effort, respectively. Phase two results showed no significant difference in probability of sincere effort between raters or between testing sessions. Conclusion: A performance criterion that accurately identifies sincere vs insincere group membership during functional evaluations was identified. There were no significant differences between raters or between testing sessions. These findings indicate that this test is reliable and possesses good predictive validity in assessing sincerity of effort.

Jan 1, 2003

The twelve latexes listed in Table XI penetrated A horizon soil as shown by elution through a laboratory soil column and gave good sealing efficiency. See details in Table XII. High elution through laboratory soil columns of 4 to 6 inches depth is desirable because it predicts penetration of latex to a greater depth in the field. No definite correlation was evident between penetrating ability and particle size, surface tension, or pH. Most of the materials, however, were characterized by low surface tensions in the 36 to 53 dynes/cm range while particle sizes were usually in the intermediate range of about 1500 to 2500 Å. Naugatex J-3471 (a highly crosslinked styrene-butadiene copolymer) was the most promising of this group for stability, penetrating ability; and sealant efficiency. It also showed utility with [B] profile soil. Many of the other latexes tested in this investigation showed good sealing efficiency but were judged unsatisfactory because they gave low penetration or formed surface films with & horizon top soil. In general, latexes containing cationic surfactants were not satisfactory because they formed a heavy surface film. This is due to neutralization of the positive latex charge by the negatively charged soil particles.

Jan 1, 1972

By George L. Atwood, William Brown

Phosphate ore is being mined at Monsanto Co.'s Henry mine, near Soda Springs, Idaho, for the company's three furnace elemental phosphorus plant near Soda Springs. The finished product from the furnaces is elemental phosphorus which is subsequently used in the manufacture of detergents, food preservatives, fire retardants and other consumer items. In stripping and mining, D-9 crawler tractors are utilized to rip and push-load rubber-tired scrapers. The equipment consists of six D-9G crawler tractors, four Caterpillar 657B scrapers, eight Euclid S-24 scrapers, one Reich T750 drill and one Caterpillar No. 16 patrol plus various support equipment. Stripping is performed on a 12- month basis, two shifts per day, whereas mining is mainly in the summer months on a one-shift basis. The hauling season begins May 15 and ends November 1 due to freezing weather and snow conditions. Annual production is 1 million tons of phosphate rock and 2.5-3 million cu yd of stripping. Stripping, mining and hauling is performed for Monsanto by Dravo-Soda Springs, a mining contractor which owns, operates and maintains all equipment used. The contractor is paid for stripping by the bank yard and for ore mined and hauled on a tonnage basis.

Jan 8, 1972

By M. Steyn

This article captures the intrinsic differences of thermal coal products, their utilization and their substitution characteristics. South Africa produces approximately 245 million tonnes of coal annually. Eskom consumes 46% (approximately 112 million tonnes), 26% (approximately 65 million tonnes) is exported, and SASOL Synthetic Fuels consumes 18% (approximately 44 million tonnes) and a further 9% (approximately 22 million tonnes) is consumed by domestic users in various different industries. Marketing theory contributes significantly to understanding the importance of technical product and quality appreciation and comprehension, encompassing elements of price, distribution, and promotion. Coal product specification is determined by the inherent geology of a resource and the number of complex actions to market the product to a specific consuming market. Sampling, analyses, beneficiation application, and an array of parameters contribute to matching thermal coal products to the value-in-use it provides to the different markets and its consuming industries. Coal producer shave come under increased scrutiny since South Africa has been experiencing electricity shortages since early 2008. General misunderstandings were declared on public forums and in the media by both legislators and the South African public since a perception developed that South African coal producers are exporting coal that could be utilized by Eskom.

Jan 1, 2010

By R. H. Barham, G. W. Nabor

Linear aquifers, either limited or essentially infinite, may be encountered in reservoir engineering practice. In areas where faulting fixes reservoir boundaries, the fault block reservoir may have an aquifer of limited extent whose geometry is best approximated as linear. An infinite linear aquifer can occur as a regional feature whenever water movement through the aquifer member is constrained to one direction. Such constraints can arise from major faults, facies changes or pinchout of the member. Miller* pointed out that linear aquifers have received only meager attention in the past. He analyzed the performance of finite and infinite aquifers, developed working equations and curves, and presented examples. While Miller's curves may be used fairly easily, a separate one is required for each size of aquifer. In this paper, Miller's equations have been used as a starting point. By modifying them slightly, they can be reduced to a form which yields a single working curve, applicable to any size of aquifer. Thus. interpolation between curves is eliminated and accuracy is improved. Miller's results for finite aquifers covered only the boundary condition of no flow across the outer aquifer boundary. This paper also includes the case of constant pressure at the outer aquifer boundary.

Jan 1, 1965

The word "engineering" should not be considered as all-inclusive. Perhaps it should be redefined at this time. Various fields of learning that are indispensable to the locating, beneficiating, processing and using of minerals cannot be classified properly as engineering. For example, in locating deposits, the sciences of paleontology, stratigraphy, mineralogy, petrology, petrography, geo- chemistry, economic geography, and mineral economics might be involved. Beneficiating, processing, and using go beyond the normal scope of engineering to include fuel technology, physical and organic chemistry, physical and atomic metallurgy, and ceramics. Fifty-eight institutions of higher learning in the United States offer curricula in one or more subject-matter fields of the mineral arts and sciences. Thirty-four curricula are offered in mining; 42 in metallurgy; 17 in petroleum and natural gas; 13 in ceramics; 1 in fuel technology; 23 in geological engineering; 8 in geology; 4 in geophysics; 2 in mineral preparation; and l in mineral economics.1 Under given conditions, some of these curricula probably could be eliminated without the slightest retardation in the rate of advancement of knowledge concerning the science of mineral discovery, extraction and utilization, but it is no credit to mineral industries colleges that five departments of mining per-

Jan 1, 1950

Important chemical and other technical engineering work necessary, for the prosecution of this war is being carried on by the Bureau of Mines Experiment Station, at Washington, D. C. The services of trained men of the following classifications are urgently needed Bacteriologists Instrument makers Biologists Laboratory Assistants Chemists, Inorganic Laborers Chemists, Organic Machinists Chemists, Physical Physiologists Chemists, Electro- Plumbers Chemical Engineers Steamfitters Draftsmen Stenographers. Electrical Engineers Skilled labor of various kinds If your training fits you for any of these occupations, send to the Bureau of Mines, American University Experiment Station, . Washington, D. C. for blank forms. When properly executed and returned by you, these forms will be placed on file, and when a vacancy occurs you will be considered for it and will be notified if your services are desired. If you are a registrant in the draft, and have not yet been- ordered to camp, it may be possible to have you immediately inducted into the service for work here. If you are not in the draft, but feel that you wish to serve your country in the present crisis, you can enlist, or serve as a civilian. Serve your country where you can serve it best. VAN H. MANNING, Director.

Jan 6, 1918

By Owen E. Owens

INTRODUCTION This paper deals with the main components in exploring for and developing a gold ore deposit. It addresses geology, exploration drilling, ore reserves, and evaluation criteria in an integrated manner to present an overall picture. Gold forms such a small component of a gold ore body, that particular care should be taken in dealing with the data from a developing deposit. The paper lists the main gold ore deposit types and their character. Their differences, as well as differences to other types of ore deposits, are important to understanding exploration approaches, and problems of ore reserve definition. Gold exploration has enjoyed a great boom in recent years. Many new ore deposits have been developed but experience shows that definition of gold is not a simple straight forward process and this outline attempts to point out some of the important aspects of ore reserve definition including some pitfalls. GOLD DEPOSIT TYPES The Witwatersrand deposits in South Africa produce about 50% of the world's gold. The gold occurs as fine grains in thin beds within gently dipping quartz pebble fan conglomerates usually with associated pyrite grains. It is characterized by rather uniform distribution of gold along thin layers within the conglomerate.

Jan 1, 1988

By W. F. Kane

Underground geologic mapping is an extremely important aspect of any on- going ground control plan. However, the actual use of data derived from such a program is difficult and often leads to subjective analysis. In this regard, computer software has been developed that utilizes a statistical determination of unstable ground conditions based on geomechanical and operational data and collected by mine personnel on a mine-wide, or regional basis. Categorical variables, such as faulting or joint frequency, are selected from local experience to form the framework of a representative data base. Statistical comparisons between the selected variables and a particular ground control problem are conducted and correlations subsequently made. The probability of encountering unstable conditions in virgin areas is assessed as information from these regions is gathered. This data can be derived from surface mapping, cores, and/or geophysical logs. As mining progresses, new data is merged with the existing data base to form a more comprehensive and extensive unit. The advantages of this approach and the acquisition and maintainence of a large data base include the more accurate representation of existing mining conditions, increased confidence in analyzing future problem areas, and elimination of the difficulties which arise when using ground control theories derived for other, often very different, locales.

Jan 1, 1986

Cleaner Production stands for a proactive and preventive approach to industrial environmental management and aims for process- and/or product-integrated solutions that are both ecologically and economically efficient (æeco-efficiencyÆ). Pioneers in the field were large manufacturing and processing industries in the USA (since the late-1970s), but it took until the early-1990s before Cleaner Production was generally recognised as a valuable approach for large and medium sized enterprises. The application of Cleaner Production in mining and minerals, metals and energy production appears to lag behind other sectors, such as manufacturing and processing. This paper starts with a discussion of the Cleaner Production concept and provides examples of its application from a few selected Australian mining and minerals processing industries. This evidences that Cleaner Production can achieve significant reductions in environmental impact, in terms of reduced waste and emission generation and in terms of conservation of materials, energy and water, while simultaneously reducing operating costs. The paper then investigates a number of key issues pertaining to the implementation of Cleaner Production; ie organisation and management of Cleaner Production activities, effective tools for mastering the Cleaner Production concept as a way of life, and performance measurement.

Jan 1, 2002

By L. Lichty, R Bhappu, R. Rowan, G. Ramadorai

Treatment of refractory gold ores containing arsenic have always presented a major problem in their processing to recover the contained precious metal values. The major difficulties are concerned with lower recoveries, production of hazardous fumes, effluents and residues. Because of'these arsenic related problems, many otherwise economically attractive precious metal deposits and dumps all over the world are not exploited. In recent years, treatment processee for refractory gold ores and concentrates have been explored and a few commercial operations employing roasting or pressure leaching have resulted. Roasting has limitations due to environmental constraints related to off gases. Pressure leaching involving high temperatures (180% to 200%) and pressures (400 psi) is accompanied by high capital and operating costs. An alternate route to roasting for treating pyrite and arsenopyrite ores and concentrates ia the "lime-oxygen hydromet" process carried out at a moderate temperature (100%) and pressure (100 psi). A simplified process for treating such arsenic containing ores and concentrates utilizing low temperature and pressure oxidation is presented. This low cost treatment with compressed air and lime renders arsenic as an inert component in the residue, meeting all the requirements of the EPA Toxicity Test. The precious metal values are then extracted from the autoclaved residue by standard cyanidation. This paper discusses this new development.

Jan 1, 1990

By A. K. Dikshit, H. R. Murty, S. K. Gupta

This paper deals with the development of environment performance indicators (EPIs) for the steel industry. Environmental performance has become one of the key measures of business success. Emergence of continuing pressure from customers, employees, government and NGOs for environmental performance evaluation (EPE) of industries has led to evolve a framework for the development of sector specific environmental performance indicators. EPIs can be used by steel industry for assessing the continual improvement in environmental perfromance, selecting various eco-friendly options, benchmarking, environmental reporting, technology assessment and dissemination, evaluating environmental impacts and building EPIs based environmental management systems. The objective of this paper is to develop EPIs for steel industry and provide framework for development of environmental performance indicators based environmental management system and its integration with the overall management system. An indepth discussion has been presented concerning identification of EPIs, eavaluation of significance of EPIs, their prioritization and its integration with Environmental Management Systems. A new methodology has been proposed for implementing EPIs based environmental management systems . The material presented is derived in part from PhD studies of Rajesh Kumar Singh.

Jan 1, 2005

By S. Banisi, J. A. Finch, A. R. Laplante

"A technique for on-line simultaneous estimation of gas and solids holdup (volume fraction), based on a combination of conductivity and pressure difference measurements, is proposed and tested in a laboratory flotation column (10cm in diameter and 447cm in height). Fundamental concepts underlying this technique and the effect of relevant parameters are discussed. In the studied range, 3-30 %v/v gas holdup and 2-18 % v/v solids holdup, experimental results showed good agreement between the estimated and actual holdup values (as determined by an isolating technique). The relative accuracy of the solids holdup estimation increased when solids density or solids concentration increased. Frequent re-calibration of pressure transducers was found necessary for accurate phase holdup estimation.IntroductionGas holdup is a key parameter in controlling the performance of flotation columns. For example, flotation rate is affected by bubble size and gas rate both of which, in turn, affect gas holdup. Moreover, gas holdup also determines the slurry residence time which indicates a direct influence of gas holdup on recovery.Gas holdup determination has been the focus of many studies (e.g., Castillejos, 1986; Marchese et al., 1992). Some of the techniques which have been used are given in Table 1."

Jan 1, 1994

The development of reliable and accurate solution sampling systems plus on-line atomic absorption spectrophotometers and voltammetric analysers at Pasminco Metals - EZ's (PMEZ) zinc refinery at Hobart, Tasmania, has led to extensive implementation of On-Stream Analysis (OSA) throughout the hydrometallurgical circuit. These systems complement industrial autotitrator and colorimetric analysers and with the comprehensive use of a powerful integrated Distributed Control System (DCS), provide extensive monitoring and control of all the important in solution' parameters for the plant. Samples can be left unaltered, or filtered or settled, to remove solids. They are then precision diluted and pneumatically transported to analyser shelters, where they are analysed for zinc, acid, copper, cadmium, lead, antimony, cobalt, nickel, mercury and ferrous, ferric and/or total iron. The range of analyses depends on the sample itself. The results are used for feed forward and/or feedback control of reagents where possible, or simple trend monitoring and out-of-specification alarming when closed loop control is not practical. The overall system reliability and accuracy is such that many daily composite plant samples are no longer analysed off-line. Operator sampling has also been reduced, and in two places, autotitrators with automatic sample pre-treatment have been installed for preparing and analysing samples collected by operators.

Jan 1, 1993