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By J. D. Ramsdell

The object of this investigation by the Federal Bureau of Mines was to evaluate the workability, recrystallization characteristics, and mechanical and physical properties of high-purity electrorefined vanadium. The low level of interstitially soluble elements in electrorefined vanadium results in a soft ductile metal which responds readily to cold working by rolling, swaging, and press-forging. Hardness, strength, and resistivity increased with an increase in impurity content, but thermal expansion was independent of impurity content. The work-hardening of vanadium occurs rapidly. Most of the hardness increase occurs in the first 15 pct. of reduction in area. When vanadium is annealed, its hardness increases to a maximum when the annealing temperature is between 200° to 400° C. A sharp decrease in hardness develops as the annealing temperature is increased. An anomaly in the hardness versus annealing temperature curve is present in the 600° to 800° C. range, while all evidence of cold-work is removed at annealing temperatures above 900° C.

Jan 1, 1961

By Robert Torbin

The objectives of the Continuous Shaft Lining (CSL) System are to reduce the costs, safety hazards, and time currently required in lining mine shafts with concrete. The CSL will line machine bored shafts downward from the shaft collar on a continuous basis using an inverted, pressurized slipforming technique. The technique for slip-forming downwards has been demonstrated and refined under this program. The approach taken involved laboratory scale testing of key features of the CSL concept. These feature tests included concrete distribution, concrete sealing, concrete slipforming and development of a reliable concrete mix. Based on these results, a full scale above-ground test facility and CSL were designed and fabricated. The objectives of these tests were to demonstrate the viability of the basic concept; to establish operating limits; and to provide input data and information for the design of a second generation shaft lining system. The results of the program have led to a CSL design and operational philosophy which will need to be tested in an underground environment before industry will accept the technology. However, the next generation CSL promises to meet all the original program technical objectives.

Jan 1, 1983

By Arthur Wade

The most important development in connection with the search for oil in Australia during 1940 was on the legislative side. Prior to 1939 legislative enactments in the various states with regard to prospecting for petroleum were such as to prohibit large-scale effort and to bar the major oil companies from operating. The preparation of the Wade Model Bill for the Commonwealth Government in 1939 and the acceptance of the Bill in principle by all States, has gone far to remove these obstacles. Amending Acts, largely based on the Alodel Bill, have now been passed by all States with the exception of New South Wales and Tasmania. In New South Wales an Amending Bill is being drafted, while the Govern-ment of Tasmania is preparing to introduce an Amending Bill provided there is any demand for it. Noteworthy developments followed immediately on the passing of these Amending Acts. The Shell Company (1)1 and the Superior Oil Company of California (2) too$ up large areas in Queensland and com-menced work during 1940. Caltex acquired a big tract of country in the Kimberley district of Western Australia (3) and has made application for an area in the Territory of Papua. An Australian company, The Phoenix Oil Extraction Co., has obtained a permit to prospect over an extensive area bordering the south coast of Western Australia (4). Other developments are foreshadowed. The Shell Company is making an intensive examination of its area in Queensland (I). Geological, geophysical and aerial surveys are in progress. Caltex has three geological parties in the held in Western Australia while Superior Oil Company of California has done some geological work in the interior of Queensland (2). None of these concerns envisages a drilling campaign in the near future. Much exploratory work is necessary. Further work has been done by the companies that were already operating in 1939, though an important Australian company - Oil Search—has abandoned the work of prospecting in Australia. This company has subleased its holdings, at North West Cape in Western Australia (;), to Caltex on a royalty basis. The company also maintains its holdings in, and connection with, the Australasian Petroleum Company Proprietary Limited, which is a combination of Standard Oil (New Jersey), Anglo-Iranian and Oil Search. This company is operating in the territories of Papua and New Guinea. Drilling Victoria.—Although a good deal of drilling was done in the LaBes Entrance Tertiary Basin of Victoria (7), no appreciable production of oil was obtained. In order to test the extent and possibilities of the oil-bearing sand in this region, the Commonwealth and State Governments jointly put down six scout boreholes to depths of between 1200 and I500 it. The results were nega tive. A deeper exploratory horehole put down by the Governments at Seacornbe, or 26

Jan 1, 1941

By Arthur Wade

The most important development in connection with the search for oil in Australia during 1940 was on the legislative side. Prior to 1939 legislative enactments in the various states with regard to prospecting for petroleum were such as to prohibit large-scale effort and to bar the major oil companies from operating. The preparation of the Wade Model Bill for the Commonwealth Government in 1939 and the acceptance of the Bill in principle by all States, has gone far to remove these obstacles. Amending Acts, largely based on the Alodel Bill, have now been passed by all States with the exception of New South Wales and Tasmania. In New South Wales an Amending Bill is being drafted, while the Govern-ment of Tasmania is preparing to introduce an Amending Bill provided there is any demand for it. Noteworthy developments followed immediately on the passing of these Amending Acts. The Shell Company (1)1 and the Superior Oil Company of California (2) too$ up large areas in Queensland and com-menced work during 1940. Caltex acquired a big tract of country in the Kimberley district of Western Australia (3) and has made application for an area in the Territory of Papua. An Australian company, The Phoenix Oil Extraction Co., has obtained a permit to prospect over an extensive area bordering the south coast of Western Australia (4). Other developments are foreshadowed. The Shell Company is making an intensive examination of its area in Queensland (I). Geological, geophysical and aerial surveys are in progress. Caltex has three geological parties in the held in Western Australia while Superior Oil Company of California has done some geological work in the interior of Queensland (2). None of these concerns envisages a drilling campaign in the near future. Much exploratory work is necessary. Further work has been done by the companies that were already operating in 1939, though an important Australian company - Oil Search—has abandoned the work of prospecting in Australia. This company has subleased its holdings, at North West Cape in Western Australia (;), to Caltex on a royalty basis. The company also maintains its holdings in, and connection with, the Australasian Petroleum Company Proprietary Limited, which is a combination of Standard Oil (New Jersey), Anglo-Iranian and Oil Search. This company is operating in the territories of Papua and New Guinea. Drilling Victoria.—Although a good deal of drilling was done in the LaBes Entrance Tertiary Basin of Victoria (7), no appreciable production of oil was obtained. In order to test the extent and possibilities of the oil-bearing sand in this region, the Commonwealth and State Governments jointly put down six scout boreholes to depths of between 1200 and I500 it. The results were nega tive. A deeper exploratory horehole put down by the Governments at Seacornbe, or 26

Jan 1, 1941

By S. Sridhar, R. E. Aune, M. Hayashi

Thermophysical properties of silicate melts are strongly structure dependent. It is well known that the viscosities of slags increase with increasing the degree of polymerization of silicate anions. Even the thermodynamic properties of slags are dependent on the types of species and the population of the same in the melt. Thus, a link between the thermophysical and thermochemical properties of silicate melts is logically expected. The present paper elucidates the salient features of Darken?s excess stability approach to the Gibbs energies of solutions as applied to the viscosities of silicate melts. It is demonstrated, that the second derivatives of the viscosities of binary silicate melts with respect to composition indicate a maxima corresponding to the existence of stable compounds in these systems. The concept was successfully applied to the following systems: Al2O3-SiO2, CaO-SiO2, FeO-SiO2, MgO-SiO2and MnO-SiO2. In all the cases, the second derivative plots of viscosities with respect to composition showed peaks corresponding to the metasilicates. The second derivatives of the activation energies of viscous flow with respect to temperature has earlier been shown to reflect the formation of associates/embryos in the homogeneous silicate melts, indicating the readiness of the melt to separate a solid phase. Thermodynamic coupling of thermal diffusivities in the case of the system CaO-Al2O3-SiO2from the laser-flash measurements of these slags as a function of temperature are examined as part of the present study. Densities are estimated from integral molar enthalpies in the case of silicate systems and the results are presented. Keywords: silicate melts, viscosity; activation energy, thermal diffusivity; density

Jan 1, 2004

By Robert Griesbach

One of the important decisions in the development of new mining concentrator projects is the electric power supply for the project. Key decision factors often include the production of power on site versus purchase of power from the grid, ownership of the power supply infrastructure and the choice of generation technology. In this sense, the paper introduce a methodology that will allow the evaluation of the various alternatives to supply electric power to remote mining and mineral processing sites in a consistent and equitable manner taking into account economic and technical considerations and providing the same degree of availability and reliability. The most employed evaluation method consists of carrying out trade-off studies between the various alternatives but care should be exercised so that the alternatives analyzed offer comparable operational results.

Sep 14, 2009

The Crown Minerals Act provides a new+framework for the management of Crown owned minerals and requires that regard be had for the principles of the Treaty of Waitangi. The Act requires the preparation of Minerals Programmes to achieve the Act's objectives of efficient allocation of rights and the recovery of a fair financial return on its minerals. Efficient allocation requires that a permit is allocated to the party which values it most highly. A fair financial return to the Crown must be considered in the context of the economic rent available from individual mineral projects, with the proviso that a nil return to the Crown as the owner of the resource will not be considered a fair return from the community's perspective.

Jan 1, 1992

By NEFE AEWFW

Changes in the 1980 quantity and value of the sales of various natural abrasives, compared with the data for 1979, were of a mixed nature. Output of garnet and special silica stone products increased in both tonnage and value during the year, while emery and tripoli-type materials production decreased in both tonnage and value. The reported quantity and value of sales of manufactured abrasive material-fused alumina and alumina-zirconia, silicon car-bidet and metallic iron and steel shot and grit-also decreased for 1980. [ ]

Jan 1, 1981

By F. N. Shi

Ore breakage characterization plays an essential role in the design and optimization of comminution circuits. Recently, the JKMRC comminution research team has developed a Rotary Breakage Tester (JKRBT). The JKRBT uses a rotor-stator impacting system, in which particles gain a con-trolled kinetic energy and are impacted against the stator, causing particle breakage. The first unit of industrialised JKRBT was installed at the Anglo Research in South Africa in March 2007, and five more JKRBTs are currently being fabricated for some of the world?s major mining companies. In addition to the JKRBT, an improved breakage model has been developed at the JKMRC, which more accurately describes the effect of specific energy, particle size and incremental breakage caused by repetitive impacts. The validation outcomes show that the JKRBT, together with the new breakage model, generate statistically similar breakage parameters to the traditional drop weight tester (DWT), but with significant advantages over its predecessor. The limitations of the DWT, specifically its lack of precision of the energy input, the lengthy time required to run individual tests and the challenges en-countered in testing small particles, have all been overcome by the JKRBT. The recent developments in the JKRBT and the new breakage model offer several prospective applications. These developments have the potential to revolutionize the ore breakage characterization in the years to come.

Jan 1, 2014

By Forrest T. Moyer, J. I. DAVIS, JOSEPH H. SCHUSTER, E. K. ELSNER

The National Safety Competition conducted by the Bureau of Mines, United States Department of the Interior, is held each year for the purpose of promoting safety in the mineral industries of the United States. Since the program was inaugurated in 1925, twenty-three safety competitions have been held. This publication is a report of the results of the contests held in 1944, 1945, 1946, and 1947. The names of plants that have been awarded "Sentinels of Safety" trophies and Certificates of Achievement in Safety dur- ing these years, together with a summary of their achievements in injury prevention, are listed. Statistical data covering the injury experience of all plants entered in the annual contests also are included in this publi- cation. The injury statistics of these plants, arranged in the six groups of the competition, are the only data on injury severity at mineral operations available to the Bureau of Mines. Interest in the National Safety Competition has increased steadily. The number of participating plants has increased from 210 in 1925, the first year of the competition, to the record number of 494 in 1946. The widening scope of the competition means that a steadily increasing number of the mines and quarries in the United States are participating in a program that will supplement their other activities in promoting safety. Safety competitions have long been recognized as instrumental in stimulating and holding the interest of employees and officials in accident-prevention work. During the years covered by this report, conditions in the mineral industries of the United States were hardly conducive to setting records in accident prevention. During the war years, handicaps were especially severe- loss of skilled employees to the armed forces or to higher-wage war industries, greater production by a smaller force of workers, relatively high rates of labor turn-over, the longer workday in effect through 1944 and 1945, and difficulties in obtaining repairs and replacement for badly worn machinery. Even the immediate postwar period has brought no abatement of the tremendous pressure upon the mineral industries for greater production. Although there was a decrease of 18 in 1947 from the record enrollment in 1946, these oper- ations worked 160,525,025 man-hours, the greatest number of man-hours of exposure to mining hazards in any year of the contest except 1942. Despite the accelerated pace at which the mineral industry worked during the 4 years covered by this report, participants in the National Safety Competition have achieved creditable performances in the promotion of safety. In fact, the injury-severity rate in the enrolled plants in the 1947 contest was 7.315 days for each thousand man-hours worked, the lowest by far in the history of the National Safety Competition. The injury-frequency rate of 42.155 for each million man-hours of exposure to mine hazards in 1947 marks a favorable trend downward from the rate of 50.577 in 1946, which was the

Dec 1, 1949

By J. MacFadyen

The U.S. cement industry, including Puerto Rico, again set a record in terms of production and shipments. The increase in shipments came primarily from imports of portland cement as domestic production from produced and imported clinker gained only 1.9 Mt (2.1 million st). Clinker production as reported to the U.S. Geological Survey (USGS) was 88.6 Mt (97.6 million st), an increase of 1 percent. Gray and white portland cement production from domestic and imported clinker, estimated at 93.5 Mt (103 million st), was up 1.9 Mt (2.1 million st). Masonry cement shipments of 5.5 Mt (6 million st), which equates closely to production, was up 6.3 percent. Blended ce-ment shipments were up 35.9 percent from 2004 at 2.35 Mt (2.6 million st).

Jan 1, 2006

By Q. H. Liao, B. G. Monaghan

The options for designing slopes in complex geological conditions are reviewed. It is shown that modelling, especially numerical modelling, allows a degree of analysis that cannot otherwise be achieved. Examples are presented of how numerical modelling can be used to investigate fundamental aspects of rock mass behaviour. It is demonstrated that an important consequence of change in scale is that the mechanisms of failure also change. The complex failure of the footwall slope at Aznalcollar, a large open-pit mine in southern Spain, is discussed. Numerical modelling with UDEC (universal distinct-element code) has allowed the realistic simulation of displacements measured in the field

Jun 18, 1905

By D. Parks, A. Miller, M. McNinch, R. Jacksha

Each year, hundreds of mine workers are involved in machinery-related accidents. Many of these accidents involve inadequate or improper use of lockout/tagout (LOTO) procedures. To mitigate the occurrence of these accidents, new safety methods are needed to monitor access to hazardous areas around operating machinery, improve documentation/monitoring of maintenance that requires shutdown of the machinery, and prevent unexpected startup or movement during machine maintenance activities. The National Institute for Occupational Safety and Health (NIOSH) is currently researching the application of Internet of Things (IoT) technologies to provide intelligent machine monitoring as part of a comprehensive LOTO program. This paper introduces NIOSH’s two phase implementation of an IoT-based intelligent machine monitoring system. Phase one is the installation of a proof-of-concept system at a concrete batch plant, while phase two involves scaling up the system to include additional sensors, more detailed safety/performance metrics, proximity detection, and predictive failure analysis.

By J. E. Golsan

Barrick Gold Corporation installed an expert style control system on the grinding circuit at its Mercur mine. Barrick's main objective was to increase mill throughput by a minimum of 3%. The expert system team collected operating data and then created a knowledge base using Comdale/X expert system development software. The expert system moved from on-line "advisory" mode, testing of expert rules, to full process control in four weeks. Expert system control benefits include a 9-15% increase in mill throughput, consistent mill loading leading to less wear on SAG mill parts, and improved downstream process control.

Jan 1, 1998

By AIME AIME

Award of a Gold Medal : to the Institute. The Jury of Awards of the Jamestown Ter-Centennial Exposition has conferred a gold medal, the highest distinction within its power,. on the American Institute of Mining Engineers for the excellence of its publications during the past decade. ; A half-tone photographic reproduction of both sides of the medal is given in the accompanying illustration.

Jan 7, 1908

By Roger K. McLimans, Venkatramaiah N. Vasudev, Christian Knudsen, Stefan Bernstein, Dirk Frei

Computer Controlled Scanning Electron Microscopy (CCSEM) analyses of sediment samples from coastal regions of Kerala and Tamil Nadu states and the heavy mineral deposits of Chavara, South India, show large lateral differences in the titanium content in ilmenite due to varying degrees of iron leaching. As the depositional environments for the sands with varying degrees of ilmenite alteration are comparable, the cause for the different degree of alteration is due to differences in the primary source of the ilmenite or to differences in the geochemical history of the ilmenite grains during transport from source to deposit. The CCSEM analyses of the heavy mineral fractions show that source of sediments with a high content of titanium-enriched ilmenites, mainly the heavy mineral deposit around Chavara, resides in the khondalite belt of South India (granulite facies metasediments). The less titanium-enriched ilmenites are sourced from other rocks in the area such as the charnokites. Those conclusions are based on the high MgO content in the leached ilmenites, chemical composition of the accompanying garnets (low CaO and high MgO), and the concentration of aluminum-rich minerals in the sands.

Jan 1, 2005

By John Stubbs

Sub-Surface Shaft excavation Mine development Headframes Surface Production facilities Product storage and loading Tailings area Infrastructure Discovery Lodge Utilities Operations complex Port Marine loading Rail unloading and storage

May 1, 2013

By J. W. Sterner

The Bureau of Mines conducted studies on four makes of Japanese automobiles, three 1981 and one 1982 model years, received from three manufacturers to determine if their materials composition would present problems to the current technology used to process junk automobiles for metal recovery. One of each make of automobile was hand-dismantled to determine the materials composition. In addition, two nearly identical automobiles of each make were shredded at a commercial operation where all metal products and rejects were collected for analysis to determine metal and nonmetal distribution. The average weight of the four automobiles to be dismantled, less batteries, tools, and fluids, was 1,938.3 lb. The weight was distributed as 1,472.9 lb. ferrous and 115.6 lb nonferrous metals, 275.2 lb combustibles, 72.3 lb noncombustibles, and 2.3 lb electrical components. The dismantled automobiles, less gas tanks, fluids, tools, wheels, tires, and batteries, which were all removed from the automobiles that were shredded, contained an average of 1,389.1 lb ferrous and 101.6 lb nonferrous metals, 305.7 lb nonmetals, and 2.3 lb electrical components. In comparison, materials collected from the shredded automobiles averaged 1,304 lb ferrous metals, 80 lb nonferrous metals, and 341 lb landfill materials. There were no materials used in the manufacture of the late model Japanese automobiles that should present handling or processing problems to the steelmaking or secondary metal recyclers.

Jan 1, 1984

By García B., Wolff E.

In Colombia, northeast of Antioquia, there is a gold deposit that has produced continuously since the middle of the XIX century, located within mining title RPP-140, property of Gran Colombia Gold Segovia (GCGS) since 2010. Mining materials are taken to the “María Dama” Processing Plant where 1500 tonnes of materials are processed daily. Before 2010, the previous owner of the mining title processed about 600 tpd and directly discharged almost all tailings, given that they had no capacity to put them into final deposits. El Chocho was conceived as a final tailings deposit to store the pulp produced by the processing plant; it was divided into two phases with two dams (upper dam and lower dam) given that the presence of illegal miners at the lower phase impeded a single dam design. A squatter impeded construction of the upper dam; so afterwards, starting at the higher end was necessary (owned by GCGS), building dam 1B to store tailings in pulp; after the squatter returned the lands to the owner (GCGS), construction of tailings dam 1A was required and thus complete construction of dam 1C or the upper dam. While all of this was happening, GCGS decided to acquire a 1500 tpd filter press which currently dehydrates tailings in order to take them to the valley controlled by dam 1A. Construction of dam 1A was designed following the containment wall model, made with geotextile tubes. These improvements generated reduced pressure on renewable natural resources because water is recirculated and less fresh water contributions are required; less pressure is placed on soil, flora and fauna because the area intervened for tailings storage will have a higher storage capacity and, as such, a longer useful life.

Jun 17, 2024

By R F. G Phelps

The former Gwynfynydd gold mine is located within the heart of the Snowdonia National Park, North Wales, United Kingdom. The black shale-hosted quartz reefs have intermittently produced more than 50 000 ounces of gold since 1863. Its most recent period of operation by Welsh Gold PLC was between 1992 and 1999 when it extracted 10 000 tonnes annually from a total resource base of 180 000 tonnes. A historical mining grade of 15 grammes/tonne was recovered from the Chidlaw Reef on which all production was based. Erratically distributed gold pockets hosted in the footwall zone of a 3 - 6 m wide quartz reef characterise the mineralisation. The gold exhibits a high-nugget effect and as a consequence the accurate determination of tonnage and grade was difficult. Production was undertaken by overhand shrinkage stoping. Due to its location within a National Park certain environmental constraints were placed on the operators. The principal requirement of planning permission was that processing should take place above ground and not involve chemicals. As a result, an underground mill based on physical separation methods was constructed in response to these environmental constraints. Much of the mine discharge is related to the flow of rainwater through the workings from surface openings on the reefs. Discharge from the underground milling facility was enhanced in various metals, particularly zinc, though was reduced to legally acceptable levels using liming tanks prior to discharge into the River Mawddach. The company was required to monitor and treat all water discharged from the mine before it reached the river. The mine closed in 1999, since which time a tip re-processing has continued as part of an environmental remediation and gold supply program.

Jan 1, 2002