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By Liping Yu Che, Xiaotie Wang, Mingli Cao, Jizu Yongfu Yuan

"It is difficult separating fluorite from Ca, Ba, Si intergrowth minerals than simple from Si, using common reagents such as combination of oleic acid or paraffin soap and water glass, but the finest quality fluorite concentrate whose grade is over 96%F must be required in chemical plant.This paper studies the flotation process of native fluorite from calcite, barite and silicate minerals whose flotation properties is similar to fluorite, using new effective collector H602 and new depressor S602 that is cheaper in cost, and describes the flotation properties. In order to determine optimum flotation separation condition, the effect of pulp pH, pulp temperature, pulp density and the effect of dosage of reagents on flotation were investigated and the flotation result was provided by oleic acid collector and the results of collector H602 were compared with those of collector oleic acid in the test. The test result of ore samples shows that at moderate pulp pH values (10.5-11.5) and other moderate technical conditions, the fluorite mineral can be obtained by new reagents and the rational reagents combination. The conclusion is 98%F of fluorite concentrate can be obtained, using the combination of H602 and S602 and only 5 steps in techniques. The paper discusses the mechanism of the flotation separation of fluorite mineral from intergrowth minerals."

Jan 1, 2003

By J. L. van Niekerk

The proposed Gautrain Rapid Rail Link (GRRL) will require approximately 15 km of double or twin high-speed rail track tunnels located for the greater part beneath the northern suburbs of Johannesburg, including Houghton, Rosebank and Sandton. During the Environmental Impact Assessment (EIA) it became clear that potential surface vibration above and in the vicinity of the tunnels was a matter of serious concern to the residents of the affected properties and that the impact required assessment. The general method proposed is based on a US Department of Transportation, 1998, publication in which abase vibration curve derived for typical high-speed passenger trains is adjusted for the topological, geological and other features to predict the surface vibration and the associated ground-borne noise. The predictions indicate that some isolated areas might be impacted but that the impact will likely be limited, and it is possible to mitigate the impact using suitable track construction methods and track support systems.

Jan 1, 2004

During the extensive research which has been conducted in the Metallurgy Department of the University of Melbourne, into the properties of lead and its dilute alloys, the Brinell test has been used for the determination of hardness.The work described herein represents part of an investigation into the influence of various factors on such determinations, particularly when carried out on different qualities of "pure" lead. It is intended to publish the more theoretical and controversial aspects of this research elsewhere.MATERIALS USED AND THEIR PREPARATION FOR TESTINGThe tests to be reported have been conducted on a specially pure electrolytic lead, and several brands of commercially "pure" lead. The analyses of the samples upon which most of the work has been carried out are given in Table 1.Note: Oxygen was not determined, but from the work of H. W. Worner, in the Rosenhain Memorial Laboratory, it appears probable that it was approximately 0-0003% in all samples.

Jan 1, 1940

By R. A. Cattell

Since the return of the Petroleum and Natural Gas Division of the Bureau of Mines to normal peacetime functions following World War II, a coordinated program of oil and gas development and production research has been in prog- ress, and the importance of the problems has been evaluated so that the Bureau can render greater service to the oil and gas industry. Among the problems associated with development and production research, those concerned with efficient utilization of the Nation's reserves of hydro- carbons contained in gas-condensate type reservoirs continue to receive major emphasis. For a number of years an important part of the Bureau's work has been the study of two pressing problems associated with production from such reservoirs; first; an investigation of fluid properties, and the second, finding a means of controlling corrosion. Studies of the characteristics of gas-condensate fluids have resulted in the publication of a number of reports, which cover a broad field. In general they deal with subjects such as the properties of a fluid from a well; development of research equipment, means of combatting corrosion, and the many aspects of gas-condensate engineering. To provide experimental data on relative liquid and gas volumes and critical pressures and temperatures, a windowed cell was constructed that permits ob- servation of the fluid phase while making the tests. Experimentation in the field on the use of inhibitors to control corro- sion of equipment in gas-condensate wells has disclosed that solutions of chromate are effective retardants of corrosion. Engineering field studies of the Carthage and New Hope gas-condensate fields are in progress, and reports on the Sheridan and Lake Creek fields have been completed. Following a plan of making studies of important newly discovered oil fields, the Bureau is investigating the physical properties of reservoir oil

Dec 1, 1948

By J. Drzymala

Particle beneficiation tests are often conducted to determine how the recovery of a key component of a particle mixture varies with overall product yield, i.e., the separation curve. The results can be misleading when an attempt is made to determine the effect of feed grade by comparing separation curves representing different feed grades or key component concentrations. This is a shortcoming of the conventional recovery versus yield diagram, which may not appear to be affected by feed concentration. To overcome this shortcoming, a method is presented for transforming and normalizing the recovery and yield coordinates so that the separation curves representing dif-ferent feed concentrations are directly comparable.

Jan 1, 2007

By Hamed Mirzadeh

The hot working behavior of 17-4 PH stainless steel was studied using the hot compression test at temperatures of 950-1150 °C with strain rates of 0.001-10 s-1. A step by step procedure for data analysis in hot compression test was given. The work hardening rate versus stress curves were used to reveal whether or not dynamic recrystallization (DRX) occurred. At low Zener- Hollomon (Z) parameter, this material showed a new DRX flow behavior, which was called Multiple Transient Steady State (MTSS). At high Z, as a result of adiabatic deformation heating, a drop in flow stress was observed. The general constitutive equations were used to determine the hot working constants of this material. Moreover, after a critical discussion, the deformation activation energy of 17-4 PH stainless steel was determined as 337 kJ/mol.

Jan 1, 2010

In the minerals industry allocating capital for setting up a new project or for upgrading an existing facility usually requires that a compromise be found between the initial cost of equipment, its operating performance and on-going operating costs. To maximise the return on the investment usually requires that various possible combinations and layouts of equipment be assessed. This task is both difficult and time consuming. Computer simulation can be used as a means of determining the expected operating performance of a range of alternate equipment configurations. Simulation is a particularly important technique for analysis as it is one of the few approaches that allows the analyst to take into account the variability inherent in a mining process. While computer simulation is a well established technique its use, until recent years, has been limited to large organisations with access to substantial computing facilities. However, with the current availability of low cost computing platforms combined with easily understood animated displays, simulation is now becoming more widely used across the industry.

Jan 1, 1990

By Katherine A. Klein

Refuge chambers may potentially save the lives of miners during a mine emergency. For this reason, it is crucial that miners know how to operate them. Unfortunately, because refuge chambers provide so many services, they can be very complicated and difficult to operate. Therefore, NIOSH has created this document with suggestions for developing manuals and educational materials. A multidisciplinary team comprised of NIOSH engineers, sociologists, psychologists, health communication professionals, and geologists developed the recommendations contained in this document. These recommendations are based on an evaluation of manufacturers? instruction manuals from both the U.S. and globally, interviews with over 20 mining and safety experts, and an extensive literature review. This research, focused on the best practices for refuge chambers, led to the formulation of this document. It is intended to offer suggestions to manufacturers and mine operators on how to create effective and easy-to-understand training manuals for miners as well as tips to create the most comfortable and usable refuge chambers. It should be noted that these recommendations are not meant to substitute for manufacturer-supplied materials but rather to be used in conjunction with manufacturer?s materials. Manufacturers should always be consulted for up-to-date information about their chamber. Although different states and different mines refer to underground refuges by different names, this guide will simply refer to underground refuges nearest to the face as refuge chambers, whether inflatable from a skid or constructed from steel. Other popular terms for refuge chambers are rescue chambers, rescue shelters, and refuge shelters. Refuges that are nearer to the shaft, whether a prefabricated refuge chamber or one built into a crosscut, will be referred to as outby refuges because of their location in the mine. Outby refuges can be permanent, semipermanent, or portable and are usually located at every other SCSR cache. Outby refuges are sometimes called hardened rooms, outby shelters, and in-place shelters. When discussing outby refuges and refuge chambers collectively, this guide will refer to them as underground refuges. Other terms for underground refuges include refuge alternatives, locations of safety, and safe havens. This document is designed to be read either cover to cover or by specific section. It is recommended that on first read, this guide be read cover to cover. In subsequent readings, manufacturers and mine operators may find it easier to use the table of contents page to locate specific information on parts of the refuge chamber.

Jan 1, 2009

By William L. Rice

This Bureau of Mines Open Pile Report on cobalt is one of a series of minerals availability commodity deposit abstracts. Nonconfidential information from the Minerals Availability Program data base covering domestic and foreign cobalt properties and deposits has been abstracted for use in his report. Abstracts include applicable data on location, published reserves and resources, geology, mine and beneficiation systems, and operation information.

Jan 1, 2011

By Staff

This paper contains an outline of the history of the Sullivan mine, now owned and operated by the Consolidated Mining & Smelting Company of Canada, Ltd.; some account of the various methods by which the ore has been treated in efforts to solve the metallurgical problems which its complex character presents, and, finally, to give, as concisely as possible, an outline of the present mining and metallurgical practice along with a description of the mining and milling plant at Kimberley and the smelter and refineries at Trail, in British Columbia. EARLY HISTORY In May, 1892, Pat Sullivan, John Cleaver and Mike Holland left the Coeur d'Alene country, in the State of Idaho, to seek their fortunes in the Kootenay lake district in British Columbia. They were aided in their venture by James Cronin, afterwards locator and owner of the St. Eugene mine at Moyie. Two months later the party broke up, Sullivan and Cleaver crossing the mountains from Crawford bay on Kootenay lake to the head waters of the St. Mary's river, the course of which they followed down to Fort Steele. Here they found a good deal of excitement about the North Star mine, and, joined by "Ed." Smith, who was familiar with this part of the country, they determined to return and prospect in its vicinity.

Jan 1, 1924

Critical safety tools to locate miners underground are featured by several exhibitors at MINExpo. Communication was the buzzword for health and safety products at the 2008 MINExpo, and it is still important in 2012. Products unveiled following the Miner Act in 2006 have been upgraded and improved. Saving lives and reducing injuries through better leadership, planning and practice is the goal of every mine professional.

Jan 1, 2012

By A. David Miller, Douglas M. Barber

"The Rocky Mountain Arsenal was used by the military to produce chemical warfare agents and incendiary munitions for use during World War II and later by private companies for the production of industrial and agricultural chemicals. After an investigation performed in accordance with CERCLA confirmed significant levels of contamination due to the common industrial and waste disposal practices of the era and the discovery of over 300 species of wildlife inhabiting the land the Rocky Mountain Arsenal became a wildlife refuge and contamination cleanup efforts began. Three lime basins originally used to treat wastewater from the chemical production were decided to be contained in place, requiring a seepage barrier installed around the perimeter of the site to further prevent groundwater/contaminant migration. This case study will discuss the successful installation of a soil-bentonite cutoff wall around the area using deep soil mixing. Highlights of this case study will also include a discussion of the challenges faced due to construction activities performed with Level B Hazmat PPE requirements as well as added challenges brought on by the Winter season, after the project was delayed due to a positive air monitor detection for the chemical weapon Lewisite during construction of the work pad.INTRODUCTIONThe Rocky Mountain Arsenal (RMA), located just outside of Denver, Colorado, was established by the United States Army in 1942 to produce chemical warfare agents and incendiary munitions for use during World War II. Following the war, and as weapons production decreased, portions of the site were leased to private companies for the production of industrial and agricultural chemicals. The principal lessee, Shell Oil Company, manufactured mostly pesticides at RMA facilities from the early 1950s to the early 1980s.In 1984 an investigation began in accordance with the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and confirmed significant levels of contamination due, in large part, to the common industrial and waste disposal practices of the era. It was also discovered that over 300 species of wildlife inhabited the land in the absence of regular human activity, including a group of bald eagles, leading to the passing of the Rocky Mountain Arsenal National Wildlife Refuge Act in 1992."

Jan 1, 2015

By Shaoyang Yan, Xinming Chen, Huazhe Jiao, Huaibao Chu, Chang Wang

In terms of the technical problems of rib spalling in large mining height coal face, a long-distance advanced pre-grouting layer flexible reinforcement technology is proposed in this paper. Based on the mechanism and failure mode of rib spalling in the coal face, the mechanical properties of the aluminum plastic composite pipe were analyzed by using the tensile and compression experiment. The deformation and strength characteristics of “flexible pipe + grouting” specimens were studied by uniaxial compression test, splitting test, and shear test. The UDEC numerical simulation software was used to simulate the reinforcement effect of “flexible pipe + grouting” at different positions. Combined with the field application, the feasibility of long-distance advanced pre-grouting layer flexible reinforcement technology was verified. The test results show the following: The coal face has the characteristics of brittle and large deformation. The aluminum plastic composite pipe has the characteristics of good elongation and tensile strength, which can endure the large deformation of the coal face. The “flexible pipe + grouting” can improve the tensile and shear strength of coal. The UDEC numerical simulation analysis indicated that the grouting hole layout of “flexible pipe + grouting” has a significant difference in the reinforcement effect of the coal face. Compared with single row grouting reinforcement, the reinforcement effect of double row grouting holes 1.5 m and 3.0 m away from the roof is better. According to the field application, it is feasible to use aluminum plastic composite pipe as a flexible grouting pipe to reinforce coal seam with 80–100 m long-distance pre-grouting. Long-distance advanced pre-grouting layer flexible reinforcement technology can improve the daily production of coal and reduce the support cost of the coal face. As a new method of reinforcement, long-distance layered flexible reinforcement has a significant effect on the prevention and treatment of rib spalling in large mining height coal face.

Sep 27, 2022

By Mary S. Esfandiary

U.S. scientists attempting to maintain continuous surveillance of scientific information are confronted with two acute problems: The steady, even spectacular; increase in the volume of such information and the fact that much of it is published in unfamiliar foreign languages, According to the National Science Foundation, almost one-third of the world's scientific literature is published in languages that are read by less than 5 percent of U.S. scientists. Most scientists in the United States must rely on abstract journals and translations to obtain information on developments in research and investigations conducted in the non-English-speaking countries. However, there are problems involved in procuring suitable abstracts and translations and in obtaining such information as cheaply and rapidly as possible.

Jan 1, 1961

The Burra Burra Mine is situated in complexly folded Torrensian dolomites and limestones forming the faulted axial region of a major anticline. The orebody mined was largely of secondary origin and confined between two faults, Kingston's on the west and Tinline's on the east. The orebody occurred at the junction between cherty dolomites and a clastic limestone with a large mass of marble breccia along its western margin. Secondary ore consisted of carbonates and oxides in the breccia and the ore bed and detrital copper minerals deposited as part of a clastic breccia in sinkholes and solution cavities in the dolomites and ore beds.Primary sulphides occur disseminated in the marble breccia and in stratiform habit in the ore bed. Kingston's so-called "lode" may be mineralized marble breccia.The marble breccia appears to be of diapiric or sedimentary origin and there is evidence to support a sedimentary origin for some of the copper sulphides. No igneous rocks have been discovered within 20 miles of the mine and any hydrothermal activities were probably at comparatively low temperature. The possibility of extensive stratiform and disseminated copper sulphide mineralization in the marble breccia and ore bed requires testing by further drilling and geophysical surveys.INTRODUCTIONThe re-interpretation of Burra Burra geology and ore formation discussed in this paper resulted from a comprehensive investigation of the mine and its surrounding district begun in December 1961 and in progress at the time of writing. (February 1963). The decision to investigate Burra Burra was taken after a thorough examination of records and reports of all non-ferrous metal deposits throughout South Australia and was given impetus by a report by Thomson (1963) suggesting a sedimentary origin for the copper mineralization. Although the author does not concur fully with Thomson's interpretation there is no doubt that sedimentary processes have played an important part in the formation of the Burra Burra copper deposit, nor is there any doubt that igneous activity played no part.

Jan 1, 1963

By Paul S. Goodman

This report examines absenteeism and accidents. The first section provides some background information on absenteeism. The second section examines trends in absenteeism in underground coal mines over time. The third section examines causes of absenteeism. Models were examined. The first model looks at self-report reasons for absenteeism. The second examines demographic correlates of absenteeism. The third model includes demographic and attitudinal predictors of absenteeism. The next section of the report examines the effect of absenteeism on accidents. The last section contains strategies for reducing absenteeism.

Jan 1, 1985

By Charles H. Jacoby

The solution mining of evaporites has a history of approximately 5,000 years. The insitu leaching of metalliferous ore will have many of the same characteristic problems which have confronted industry for years in the production of evaporite minerals. Basically we will be converting the less soluble forms of valuable metals into their more soluble salts and producing these in much the same manner as, for example, sodium chloride. There are a number of problems which we are faced with that are more complex and complicated and, therefore, will require a higher degree of sophistication than previously employed. One of our most important undertakings will be the clearcut definition of the problems involved. While a great deal of expertise can be drawn from the solution mining of evaporites and the oil industry, problems peculiar to the hydrometallurgical field will need to be solved. One of these is the introduction of permeability into an impermeable rock so as to expose the sought after values of metals which by volume are infinitesimal when compared with sodium chloride, potash or other type water soluble mineralization. After establishing this permeability which will be miniscule when compared to a solution cavity, there will be the maintenance of this permeability. In general, salt deposits are of a somewhat uniform chemical composition and thus their chemistry was relatively simple. Each metalliferous ore body is somewhat unique in its chemistry and will need to be treated accordingly.

Jan 1, 1974

Lead isotope measurements indicate that lead from the A.B.H. Consols mine and two transgressive veins in Browne's shaft is "Thackaringa" type and not "Broken Hill" type.

Jan 1, 1970

By D. G. Foot

The Bureau of Mines investigated energy-efficient methods for recovering potash values from process and waste brines. Laboratory pan evaporation of four chloride brines produced crude salts containing predominantly sylvite, halite, and carnallite. Six sulfate-chloride brines produced crude salts containing primarily schoenite, kainite, leonite, sylvite, carnallite, and halite. Potash grades ranged from 7.2 to 22.2 pct K20, and recoveries from 84 to 99 pct. Sylvite flotation from chloride evaporites, with amine collector, recovered 90 to 97 pct of the potash in a concentrate containing 54.3 to 60.3 pct K20. Fatty acid flotation of the high-sulfate evaporite recovered 78 pct of the sulfate minerals in a 27.8-pct-K20 concentrate. Flotation of the chloride minerals with amine collector recovered 80 pct of the potash in a 59.7-pct-K20 concentrate. Solar evaporation of 10,000 gal of brine recovered 99 pct of the potash in a crude evaporite containing 24.5 pct schoenite and 20 pct sylvite. Continuous flotation in a 100-lb/h process research unit recovered over 95 pct of the potash in schoenite and sylvite concentrates containing 28.0 and 62.3 pct K20, respectively. An economic evaluation suggested a rate of return of 3 pct for a new facility and 9 pct if. the process is adapted to fit an existing plant.

Jan 1, 1984

By Roderic A. Ellman

The new Woodrow Wilson Bridge (WWB) will replace the existing bridge over the Potomac River to connect Alexandria, Virginia to Prince Georges County, Maryland. The new WWB will extend approximately 1.1 miles across the river, with a 367-ft long bascule span in the main river channel where the water depth is about 36 ft. The subsurface soil profile consists of up to 50 ft of a soft organic silty clay layer that is very vulnerable to scour, underlain by a deep deposit of hard sandy clay. Foundation construction in the Potomac River required the use of cofferdams to allow structural concrete work to be performed in the dry. This paper will the present the types of cofferdams used to construct the foundations for the WWB replacement project. The bridge is primarily comprised of fixed spans in relatively shallow water and a bascule span over a navigation channel in relatively deep water. Foundation construction included the installation of 48? to 72? open end steel pipe piles and cast-in-place concrete pile caps. To achieve the desired bridge appearance, pile caps were required to extend below the water surface and below the existing river bottom in shallow water locations. Conventional steel sheet pile cofferdams with tremie concrete seal were used to construct fixed span, shallow water piers. Selection of deep water bascule span foundation cofferdams was governed by several factors including contraction scour, environmental considerations and cost. Potomac River cofferdams, i.e., relatively shallow depth cofferdams that are supported by the foundation piling were selected. This cofferdam system provided a shallow profile which minimized contraction scour and the amount of filling in the river. Design issues include load selection and cofferdam stability in very soft alluvial soils. Construction issues include erection sequence, tremie concrete mix design and placement procedures.

Jan 1, 2013