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By Forrest T. Moyer

To keep the mineral and allied industries informed of trends in the causes of accidents, and to point out the need for corrective measures, the Bureau of Mines collects, analyzes, and periodically publishes health and safety statistics. This report includes data for 1963 on injury experience, with related employment statistics, at coal mines in the United States. These data are presented in tabular form under the following headings: General Injury Experience Tables 1 to 6: Current data on number of injuries, degree of injury, frequency and severity rates, average severity, and related employment and production data by work location.

Jan 1, 1966

By Forrest T. Moyer

To keep the mineral and allied industries informed of trends in the causes of accidents, and to point out the need for corrective measures, the Bureau of Mines collects, analyzes, and periodically publishes health and safety statistics. This report includes data for 1963 on injury experience, with related employment statistics, at coal mines in the United States. These data are presented in tabular form under the following headings: General Injury Experience Tables 1 to 6: Current data on number of injuries, degree of injury, frequency and severity rates, average severity, and related employment and production data by work location.

Jan 1, 1966

By C. H. Manney

This report deals with the feasibility of the use of vocoders as an integral part of a mine electromagnetic voice communication system. Limitations imposed by the nature of the transmission path, background noise and equipment are examined. Some properties of vocoders and apparent advantages of the use of vocoders in a mine communication are discussed. The conclusion is reached that the man-made noise level will ultimately determine the workability of such a system.

Jan 1, 1972

By Enrique Garay

Actualmente el geólogo de mina toma información rutinaria, mapea los bancos de la mina, los taladros para voladura y loguea los núcleos de perforación y fragmentos del aire reverso. Para la localización en el campo utiliza un GPS que tiene una estación en tierra que permite triangular en tiempo real. En ese sentido, el presente texto señala la importancia de la función del geólogo y las herramientas de campo que utiliza para la exploración y la definición del modelo geológico en la mina Pierina. Así para la digitalización del mapeo geológico utiliza el programa AutoCad, en el caso de mapeo de taladros para voladura emplea un Colector de Datos que posee una hoja de calculo que permite recoger datos del tipo de alteración, porcentaje de arcillas, dureza y tipo de mineralización. Finalmente, la información que genera el geólogo de mina es útil para diferentes usuarios ya que sirve para mejorar el cálculo de reservas, manejar el control eficiente del minado de mineral y desmonte, así como generar el soporte geológico a los geotecnistas responsables del estudio de estabilidad de taludes del tajo abierto, así como desde el punto de vista ambiental es posible definir zonas con potencial de generar drenaje ácido de rocas.

Aug 25, 2002

This report deals with the Schmalfeldt gasification plant for making synthesis gas, the Fischer-Tropsch plant, the hydrogenation plant and the catalyst factory, and includes a report on lubricating oil. THE SCHMALFELDT GASIFICATION PLANT The information was obtained on May 9 and 11, 1945, from Dr. Schneeberger (director), Dr. Schneider (director and power plant manager), Herr Dassau (manager of gas plant) and Herr Schultz (manager of Fischer-Tropsch plant). The plant was shut down as the result of very heavy air raid damage to other parts of the works

Jan 1, 1946

By M. Rafie, M. Rinne, F. Samimi Namin

"SynopsisRock mass classification systems constitute an integral part of empirical underground excavation design. One system that is commonly used to classify rock mass is the Rock Mass Rating, or RMR, system. The RMR system has evolved over time to better reflect the perceived influence of various rock mass factors on excavation stability. While the introduced modifications have enhanced the applicability of this classification system, there are still areas that cause potential ambiguity. The RMR system cannot deal with input data ambiguities, uncertainties, and vagueness. To deal with the uncertainty, a Fuzzy Rock Mass Rating (FRMR) has been developed. This study aims to describe the main concept of the fuzzy approach, which is implemented in the FRMR to classify rock mass. The FRMR considers the uncertainty associated with the input data (uncertain variables) used in rock mass classification. The Gol-e-Gohar (GEG) area 3 iron ore deposits in the south of Iran were chosen as the case study for investigating the applicability of FRMR. The results of this study show that the FRMR software tool can easily be used for rock mass classification, even if uncertain input parameters have been used. FRMR consists of three parts, each of which is suitable for certain conditions.IntroductionNowadays, rock engineering classification systems, which constitute the backbone of the empirical design approach, are widely employed in both civil engineering and mining engineering. Rock mass classifications have recently been quite popular and are being used mostly for the preliminary design and planning purposes of projects. According to Bieniawski (1989), a rock mass classification scheme is intended to classify the rock masses, provide a basis for estimating deformation and strength properties, supply quantitative data for support estimation, and present a platform for communication between the exploration, design, and construction groups."

Jan 1, 2015

By Judy B. Jones, Bradley A. Crenshaw, Theodore DePooter

This paper reviews groundwater issues leading to a secondary grouting program at the Chattahoochee Tunnel that was implemented subsequent to the contact grouting program. The secondary grouting program was developed based on infiltration data, geology, and testing programs. This paper includes a brief description of the geological features encountered, as well as describing the grouting program. The success of this grouting operation has been quantified by several methods, and is presented to help others project the costs and benefits of this type of program. Review of initial results and refinements of techniques are also discussed.

Jan 1, 2005

By D. R. Torgoson, Th. G. Sahama

"This paper contains some new thermodynamic data for silicates in the series Mg2SiO4-Fe2siO4 and MgSiO3-FeSiO3 and gives the results of a thermodynamic attack on the problems of stability end parageneses.. Although some data are lacking satisfactory agreement with mineralogical and petrological observations is indicated.The use of thermodynamic methods in mineralogy and petrology has been rather limited, because accurate thermal data, especially for the more complicated and more important rock-forming minerals, have been too scanty to permit any systematic application to problems in those fields. It is, nevertheless, a fascinating task to investigate to what extent the mode of occurrence and the stability relations of the minerals and mineral parageneses, as revealed by petrological and mineralogical observations, agree with predictions of thermodynamics. At the present stage of development calorimetric data are needed for most of the abundant silicate minerals.Measurement of the heats of solution in hydrofluoric acid of minerals in the series Mg2SiO4-Fe2SiO4 and MgSiO3-FeSiO3 affords a ready means of obtaining their heats of formation from the oxides. Combination of such data with entropy and heat-capacity values gives a means of obtaining free energies of formation from the oxides, which, in turn, are connected di¬rectly with stability and paragenoses.The two silicates of magnesium, Mg2SiO4 and MgSi03, occur as rock-forming constituents as forsterite and clinoenstatite or enstatite. The orthosilicate (forsterite) forms a series of isomorphic mixtures with ferrous-orthosilicate (fayalite). The continuity of this series, suggested by petrological observations, has boon proved experimentally by Bowon and Shairer.4/ The present work shows that those minerals constitute a series of perfect solid solutions - that is, a series of solid solutions for which heats of formation from the individual pure silicates, Mg2Si04 and Fe2SiO4, aro negligibly small.The metasilicates of magnesium and iron also form an isomorphic series. However, this series differs from the forstorito-fayalite series in the fact that the most iron-rich mixtures, between about En10Fs90 and pure Fs, appear to be unstable with respect to the paragenesis iron-rich olivine plus quartz. The supposed instability of pure FeSiO3 as a crystalline compound, at least at high and at moderate temperatures, is remarkable, as no crystal struc¬tural reason for such instability is apparent. The present work indicates, also, that these minerals form a perfect series of solid solutions and throws additional light on the instability question.In the following, the samples used in this investigation will be described. For each of the natural olivines and orthopyroxenes, with the exception of sample L, a chemical analysis was made of the purified and actually used fraction. All the analytical work was carried cut by Oleg v. Knorring, and the specific gravity determinations, by moans of a pycnomctcr, by Oiva Joensuu, both of the University of Helsinki, Finland. The determinations of the optical properties were made by Mrs. Toini Mikkola, of the Geological Survey of Finland."

Feb 1, 1949

By Albert Ruiz

South Coast Water District (District) operates the Beach Interceptor Sewer Tunnel (BIST) in South Laguna, Orange County, California between Mon-arch Beach and Aliso Beach (Figure 1). The 10,424-foot long BIST houses a 24-inch Techite gravity sewer pipeline critical to the District Sanitary Sewer Collection System that conveys 1 MGD of raw sewage to a wastewater treatment plant. The original tunnel was constructed in 1954 and the sewer line replaced in 1974. Periodic inspections by sewer pipeline maintenance crews have documented deterioration of specific intervals of the tunnel within the past few years (Sancon 2003). Rotting timber supports and rock falls in the tunnel as a result of the deterioration were endangering the sewer pipeline. A 50-foot section of the tunnel was determined to be in need of immediate repairs, which were carried out from January to August in 2007. This section was enlarged to a horseshoe shape and lined with shotcrete. The pipe was encased in concrete in the invert of the new enlarged cross section. Hatch Mott Mac-Donald (HMM) designed the emergency repairs, carried out an assessment of the rest of the tunnel alignment, and is currently developing a work plan for rehabilitating the entire tunnel.

Jan 1, 2008

By O. Matwijenko

"The Kidd Creek concentrator is located twenty-six kilometres east of Timmins, Ontario, within a metallurgical complex including a 109,000 MTPY zinc plant and a new 59,000 MTPY copper smelter and refinery. A complement of 159 persons is employed in the operation of the concentrator.Ore from the Kidd Creek Mine is crushed underground to minus 15. 0 cm, then transported twenty-seven kilometres by rail 1:0 the concentrator. After being crushed to minus 1. 6 cm, the ore is further processed by grinding and flotation.The concentrator commenced operations in November of 1966 at a designed capacity of 8,200 MTPD. Two parallel flotation and grinding circuits treated copper-zinc ore (2.28% Cu, 5.63% Zn) and a third treated silver-copper-lead-zinc ore (230 g/MT Ag; 0.57% Cu, 0.88% Pb, 7.89% Zn).By 1975, the concentrator was treating 9,100 MTPD of ore. Seven concentrates were being produced, namely, high silve1: copper, low silver copper, lead, low silver zinc, high silver zinc, pyrite and tin.Planned minesite expansion to a second underground mine required increased concentrator throughput. Expansion of the concentrator enabling a thirty-three percent increase in copper-zinc ore throughput occurred during the period 1975 through 1978. This expansion included increased load-in capacity, major redesign in the crusher house, the addition of a fourth grinding and flotation circuit, the building of a fourth dryer, and numerous expansions of services."

Jan 1, 1980

By E. Lammer

"Underground mining processes are dangerous. The design of mining equipment, which is able to cope with the hostile underground environment, is a challenge for all machine manufacturers. Presupposition for realizing the vision of SANDVIK for zero harm for working with SANDVIK equipment is the installation of the appropriate processes. Into the product engineering and product development processes of Sandvik Mining and Construction, a specific "Product Safety Process" has been integrated, where all safety related activities like identification of all life cycle hazards, risk management and safety verification / validation are planned, performed and documented. Product safety shall be „designed into" the products. Therefore, specific research activities have been started, to address the safety and health related topics for the development and for the engineering of SANDVIK mining machines."

Jan 1, 2011

By L. C. IlsLey

The theory and practice followed by the Bureau of ones in the investigation of electrical equipment4/ made for service in massy mines are of particular interest not only to manufacturers but also to those organizations that deal with safety and inspection at the mines. This publication proposes to discuss the theory, upon which tests of equipment in explosive atmospheres are based and to consider inspection and other matters pertaining to investigations made bar the Bureau in ascertaining whether a machine merits approval.

Jan 1, 1941

Flotation of Phosphate Gangue from Magnetite Fines - Non-Ionic Surfactant as Atrac Collector Modifier

Sep 13, 2010

By J. M. Benson

Titanium is an exciting structural material that can offer significant strength-to-weight advantages over currently used alloys. However, its Achilles? heel is its costly, energy-intensive production process that effectively eliminates it from competing with aluminium and high-strength steels, apart from critical applications where titanium forms only a small component of the total cost. Current attempts are being made to reduce the cost of titanium products and these recognize the importance of minimizing the costs over the total production chain. Powder metallurgy (PM) technologies play a crucial role within this, as the output of the existing and potential primary metal production methods is in the form of sponge or powder. By using PM, costly remelting and forming operations can then be avoided, except in the manufacture of large components. Metal injection moulding (MIM) is an effective process for producing complex net-shape components in large volumes from metal powders. Nevertheless, the commercial use of titanium powders in this process is still in its infancy. The only major supplier of feedstock utilizes a polyacetal-based binder. This gives good green strength but requires a catalytic nitric acid process to remove most of the binder prior to thermal treatment. As this involves additional and expensive equipment and is a potentially hazardous process, there is interest in finding an alternative binder system that can be debound either purely thermally or that involves a less hazardous, more environmentally friendly solvent. This paper describes the use of capillary rheometry to characterize the influence of temperature and shear rates on the flow behaviour of potential binder systems for titanium MIM feedstock. Keywords Titanium, metal injection moulding, capillary rheology, feedstocks, powder loading.

Jan 1, 2011

By F. Block, K. Kohli

Outcrop barrier pillars serve to keep mine personnel and the public safe from sudden uncontrolled flows of water accumulated in active and abandoned underground mine workings. When an outcrop barrier fails, the result is an outbreak of water to the surface and is termed as blowout. Mine blowouts are associated with above-drainage mines and can occur through the coal outcrop and sealed portals. A blowout is often catastrophic, a threat to the people on the surface living or working in the path of a potentially large flood. In addition, blowouts can destroy homes, cause landslides and severe erosion and release pollution and acid mine drainage. This paper provides guidance on the planning, design, evaluation and inspection of barriers to address the problem of mine blowouts associated with above-drainage coal mines.

Jan 1, 2007

By J J. J Chen, J C. Zhao

A water/air model was developed to simulate the refining of molten aluminium by the sparging of gas through an impeller. The optimal gas dispersion depends upon selecting the correct gas rate for a given impeller rotational velocity to prevent flooding or channelling. Correlations illustrating this flooding behaviour exist for standard impellers within standard tank geometries. However the validity of these correlations has not been substantiated for gas dispersion in high temperature molten metals with non-standard tank and impeller dimensions. Metal refining is most efficient when fine bubbles are generated and uniformly distributed within the treatment tank. The application of some measuring technique able to detect this distribution within a non transparent operating treatment tank would be invaluable, enabling the optimisation of gas flow and impeller speed.   A technique has been developed to measure the pressure fluctuation levels at specific points in the water model. Comparison of these pressure fluctuation data with photographic evidence obtained in the water model suggests that the flow regime in the metal treatment unit may be determined using this technique.

Jan 1, 1995

By K. Wyper

"Gulf Minerals (Canada) Limited' s Rabbit Lake Uranium Operation is located in the northern portion of Saskatchewan, 198 miles southeast of Uranium City and 134 miles northwest of Lynn Lake Manitoba.This paper describes flow sheet changes to solve operating problems and briefly describes future changes to accommodate the new ""B"" Zone ore.The Rabbit Lake mill was designed to process 1600 dry tons per day of uranium ore, with an average grade of 0.370 percent u3o8. In 1981, the mill processed 2040 tons per day at a grade of 0.231 percent u3o8 . The process modifications and flow sheet changes that allowed this increase in tonnage will be discussed in relative chronological order. Mill feed was introduced on June 10, 1975, the original equipment consisted of an Ingersoll Rand hydraulic breaker mounted over a 24"" square grizzly. The - 24"" ore was fed to a 2011 X 6"" seflli autogenous grate discharge mill close circuited with 20"" cyclones, the mill discharge was screened on a tyler double deck screen with the undersize (8 rnesh) reporting to the cyclones, the screen oversize was returned by conveyor belt to the mill feed chute.The cyclone overflow (28 mesh) was thickened in a 100' diameter thickener to obtain 55 percent solids for the leach circuit.The leach circuit consisted of two slurry holding tanks and five leach tanks."

Jan 1, 1982

By V. B. Dale

This report is one of a series covering the mineral resources of the Nation. It briefly describes most of the known tungsten deposits in Gila, Yavapai, and Mohave Counties, Ariz. Many of the descriptions are taken from the reports of previous examinations by Bureau of Mines engineers, and from Defense Minerals Exploration Administration files. Where a previous examination had been made, and an inquiry disclosed that little or no work had been done since that time, pertinent information from the report was used in this paper with acknowledgment of the source. However, the majority of the descriptions is from field examinations by the author. In the past 3 years (July 1956-May 1959) only necessary annual assessment work was conducted on nearly all the properties described in this paper. There was no active mining on any of the properties examined.

Jan 1, 1961

CONTENTS.IntroductionAcknowledgementsDescription of MineVentilation of MineOrganisation of Fire Fighting SquadsTraining of Fire Fighting SquadsRescue WorkFire Fighting and Rescue EquipmentFire AlarmsConclusionINTRODUCTION.This paper should be read in conjunction with that by R. P. Hooper, entitled "Underground Mine Fire Prevention at the South Mine," Broken Hill. Contents of the paper have been arranged similarly for easy reference. The methods used in educating employees in the use of Proto apparatus remain basically the same, but many changes in the methods and equipment used in subjugating fires have been brought about by the practical experiences gained by officers of the company in extinguishing the outbreaks which occurred in the latter half of 1944.Three fires took place during this period, the first in July, on M.L. 11 in openings leading to timbered workings previously worked and subsequently abandoned by...

Jan 1, 1946

By D. M. Fraser

"Brunswick Mining and Smelting Corporation Limited operates two mines; one open pit (No. 6) and one underground (No. 12), approximately 20 miles south-west of Bathurst, New Brunswick. Both are massive sulphide deposits containing copper, lead, zinc and silver. The No. 12 property began operation in 1963 and is presently being mined at a rate of 3600 tons per day underground and is in the completion stages of an expansion to achieve 11,000 tons per day underground by the end of 1930.Originally at Brunswick Mining, acid mine drainage was added to tailings and neutralized by an excess of lime in the tailings. A conventional recycle system was established with a biostabilization pond for the treatment of thiosalts, a liming station and sludge settling area for neutralization of acidic water and a final reclaim pond with a pumping station for reclaim water.We found that not more than one third of the reclaim water could be used as it upset the flotation circuit every time it was used. It was established that the mine water and surface drainage were the cause due to oils and detergents in the water. It was also found that the biostabilization pond method Cf thiosalt treatment was not efficient for year round operation in our climate.In 1974, we reviewed the problems and began a 3 phase program to control effluents from the property:"

Jan 1, 1980