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"Accelerated expansion of Western Canada's metallurgical coal industry has again stimulated considerable exploration activity in the Rocky Mountain Foothills Belt and influenced much of the R&D related to transportation, processing and carbonization. Preparation R&D has included further pilot-plant work on desulphurization, spherical agglomeration and modified compound cyclones (which are also proving themselves in other mineral beneficiation studies). Combustion research, aside from increasingly stressing control of combustion source pollution, has directed special attention to lignite PF firing and problems arising from lignite ash. Studies directed toward the non-fuel utilization of coal have centered on such diverse topics as active carbons, carbonaceous filter media, plant nutrients and industrial applications of humic acid derivatives. In addition, a number of long-range research projects related to such matters as coal chemistry and pyrolysis have been actively pursued, and further attention has been given to improved sampling techniques and analytical methods."

Jan 1, 1969

By Z. Luo, W. Chen, Y. Zhao, Y. Fu, L. Dong

The gas-solid dense-phase fluidised bed includes a complex multiphase fluid-particle system; different complex exchanges significantly affect the stability of the fluidised bed. To elucidate the characteristics of fluidisation in a gas-solid dense-phase fluidised bed, this study used experimental performance tests to obtain the static density characteristics, and the attachment and flow characteristic of the dense medium. The results indicate that the bulk density of the dense medium increases first and then decreases with the increase of particle size. The airflow rate difference is used to quantify the wall attachment characteristics of dense medium and the average pressure gradient in the axial direction of the bed is approximately 20 Pa/mm under the fluidisation results. At the same settlement location, with the decrease of fluidisation number, the settlement velocity of large and small particles becomes slower, the boundaries of settlement displacement and location probability are gradually disrupted, and the falling velocity of particles with a radius of 20 mm is faster than that of materials with a radius of 15 mm. This work also established a theoretical basis for regulating the stability and separation characteristics of gas-solid dense-phase fluidised bed. Keywords: Fluidised bed, different size particles, fluidisation characteristics, flotation bubbles, settling motion

Jan 1, 2020

By E. A. Barrett, K. M. Kowalski

The U.S. Bureau of Mines (USBM) conducted experiments to determine if training using a latent- image, three-dimensional (3-D) slide simulation exercise improved miners' ability to recognize roof and rib hazards. The effectiveness of this innovative type of classroom training was investigated by measuring workers' performance on a hazard recognition task. The study was unique in that hazard recognition skills were assessed in the workplace using actual coal mine roof and rib hazards. Results showed that training with a latent-image, 3- D slide simulation exercise significantly improved each subject's performance on the in-mine hazard recognition task. Further, the USBM researchers concluded that transfer of learning from the classroom to the workplace occurred.

Jan 1, 1995

By H. N. Dunning

A comprehensive production research program, now in progress at the Petroleum Experiment Station of the Bureau of Mines at Bartlesville, Okla., includes studies of the displacement of petroleum from sand by detergent solutions. An earlier report (12)2/ presented the results of an extensive research program to determine the value of detergents as floodwater additives. This report presents later results of the detergent-testing program (13, 17). Although water-flooding methods and controls are constantly being improved to increase the production of oil from secondary-recovery operations, considerable crude oil commonly remains.in place after a water flood has been terminated. Therefore, the possibility of improving the efficiency of a waterflood by the use of detergents is of increasing interest. The effects of many substances on the efficiency of water flooding have been investigated in laboratory studies (5, 11, 13, 17, 19, 24). Of the various sub-stances tested, only surface-active agents were consistently effective in removing oil from sand. Results of laboratory studies presented in earlier reports (9, 11, 12, 13) show that many detergent solutions effectively displace petroleum from sand surfaces under varying conditions encountered in centrifuging, manual and mechanical agitation, ultrasonic vibration, and imbibition.

Jan 1, 1957

By LeRoy R. Curwick

This Bureau of Mines report presents the results of a study conducted to assess the domestic availability of chromium from superalloy and cast heat- and corrosion-resistant alloy scrap material. Six alloy classes included in this survey were investment cast, hardfacing, and wrought nickel- and cobalt-base alloys, wrought nickel-iron-base alloys, and heat- and corrosion-resistant alloy castings. Data were collected for 1976 on metallic scrap generation, use patterns, and production practices for these alloy producing and using industries. A model was developed that allowed an assessment of the materials flow circuits within the industries that produce these alloys. The types, amounts, sources, secondary products, and ultimate destinations of chromium- containing metallic scrap for the six alloy classes were determined. Regarding the overall recycling efficiency of these alloy producing and using industries, of the 580.9 million pounds of scrap generated from these six alloy classes in 1976, about 72 percent (416.8 million pounds) was remelted by the same alloy-producing industries, about 18 percent (104.9 million pounds) was downgraded into stainless and low-alloy steels, about 3 percent (19.7 million pounds) was exported, and about 7 percent (39.5 million pounds) was lost through landfill or other disposal or service wastage. The lost material is primarily contaminated oxides for which recovery is currently uneconomic. However, the 124.6 million pounds of scrap material downgraded or exported in 197b contained potentially recoverable critical strategic elements. The amount of scrap material lost to the six alloy-producing industries in this manner contained 22.1 million pounds of chromium, 53.4 million pounds of nickel, 5.9 million pounds of cobalt, 35.9 million pounds of iron, and 7.3 million pounds of other alloying elements.

Jan 1, 1980

By Franklin B. Woodbury

As part of its goal of helping maintain an adequate supply of minerals to meet national economic and strategic needs, the U.S. Department of the Interior's Bureau of Mines is evaluating alternative technologies to treat oxidized taconites. Since process control is an essential element in the application of these process technologies, research was performed with a prototype monitoring system. A Californium-252 neutron source and a thermal neutron capture- gamma ray spectra analysis method was utilized to measure the amount of iron and the percent solids in the process slurries. The concentrate and tailing streams in a 410-kilogram-per-hour (900- pound-per-hour) pilot plant employing a selective flocculation and cationic flotation process were monitored. The results obtained showed that the thermal neutron capture-gamma ray reaction can be used to provide process control parameters.

Jan 1, 1979

"The outlook for Eastern Canada is decreased coal production and for Western Canada increased production. The market for Western coal is expected to reach 40 million tons per year in metallurgical and thermal-power markets.Technical developments in Eastern Canada include successful methane drainage experiments, modifications to the shearer-loader to improve cutting rates, mechanized mining of a tail-gate stable and mechanical stowage of level brushing. In Western Canada, the most modern equipment is used in mining, beneficiating and shipping coal. Underground hydraulic experiments were started in 1969. The importance of reclamation was recognized and plans have been made to re-vegetate disturbed areas and mine dumps.The Mining Research Centre closed the field office in Nova Scotia and is preparing to open a new field office in Calgary, Alberta."

Jan 1, 1970

By Jefferson Caponero

The tire is an expressive component of Municipal Solid Waste, manly when its occupied volume is considered. Its treatment by pyrolysis stands for a list of advantages, such as: landfill releasing and a production of a high quality fuel. The exploitation of new natural resources is becoming more difficult each day, basically due to the environmental damages caused by this type of activity. This work presents a study on the thermal behaviour of Brazilian tires using thermogravimetric analysis and differential thermal analysis, in order to optimise the pyrolysis process of tires. Samples of I to 2 mm were investigated at atmospheres of nitrogen, argon, oxygen and mixtures of these gases at temperatures up to 1273K, under heating rates between 1 to 50 Klmin . The results showed that the behaviour of each sample is related to both the atmosphere composition and the heating rate.

Jan 1, 2001

By F. du Breuil

BCR National Laboratory (formerly Bituminous Coal Research, Inc.), under a USBM con­tract (originally with the Department of Energy), monitored the installation and operation of a computer-based belt-monitoring and control system at the Barnes & Tucker Coal Co. Mine No. 20, Ebensburg, PA. The system installed was the National Coal Board's Mine Operating System (MINOS) coal transport monitoring and control system. The program objec­tive was to document (1) the installation requirements for a conveyor control system, (2) the operating experience with the system, and (3) the impact of monitoring and control on mine operation. Analysis of the system operation indicates that monitoring and control did improve belt availability significantly, and reduced downtime associated with belt delays. Economic analysis showed the increased belt availability would potentially result in significant production increase, and, therefore, excellent payback on the initial investment. The system performed satisfactorily, was well accepted by the work force, and did not increase the maintenance workload.

Jan 1, 1987

By H. J. Struth

The benefits of proration of oil production were perhaps more concretely realized in 1932 than at any time since the oil industry adopted nation-wide production control. Reduced output of crude petroleum, which brought the daily average of the United States down to approximately 2,000,000 bbl. from a peak in 1931 of more than 2,600,000, had a telling effect on the trend of oil prices. Mid-Continent crude was advanced in price from 776, for 36-gravity oil, to $1.04 a barrel. California crude, of 26-gravity at Signal Hill, moved forward from 736 to 976 a barrel. Pennsylvania crude, the only exception to the upward trend, rose in price from $1.82 per barrel to $2.02, only to react to $1.72. This was due to local conditions which necessitated an adjustment to overcome competition from other areas of the United States. East Texas continued to exert a far-reaching influence on the crude and gasoline market during 1932. Despite the fact that oil prices were advanced in most fields, large quantities of oil were produced in East Texas in violation of state proration orders, and sold in the market at prices considerably below official postings. This created competitive conditions in the gasoline market that were felt by all refining centers of the United States. The quantity of gasoline produced from cheap East Texas crude was not large, but the volume was sufficient to influence prices in practically all sections of the country. Thus, while the industry's' economic situation showed visible improvement statistically, the unreported and unseen statistics originating in East Texas proved to be an insurmountable obstacle to the economic betterment that was otherwise apparently justified. Somewhat surprising to many was the fact that gasoline consumption was maintained within 10 per cent of the preceding year. Domestic consumption showed only a net decline under 1931 of about 8.5 per cent; exports dropped in volume to the extent of about 23 per cent. As a matter of fact, domestic gasoline consumption was only about 1.4 per cent less than it was in the predepression year of 1929. Exports, however,

Jan 1, 1933

By James Paone

Land utilized by the mining industry from 1930 through 1971 amounted to 3.65 million acres, or 0.16 percent of the land mass in the United States. Land reclaimed during the same period was 1.46 million acres, or 40 percent of the land utilized. This report includes data on land use for wastes from underground and surface mining, for wastes from mill operations, and on subsidence. Data on land use and reclamation were obtained from operating companies, mining organizations, appropriate State agencies, and others concerned with such activities. The 10 leading States in land used for mining in 1971 were, in decreasing order, Kentucky, Pennsylvania, Arizona, Ohio, California, Florida, West Virginia, Illinois, Minnesota, and Indiana. Mineral commodities accounting for a major portion of land use are, in decreasing order, bituminous coal, sand and gravel, stone, copper, phosphate rock, iron ore, and clay; for coal, these commodities are produced principally by surface mining operations. Reclamation over the 42-year period was largely on lands utilized for surface mining of bituminous coal. New surface mining methods, particularly for coal, incorporate some form of land restoration.

Jan 1, 1974

By Victoria Vaccarezza, Corby Anderson

The demand for rare earth elements for everyday technology and applications has initiated much research into the extraction and recovery of these rare earth elements. An otherwise unknown group of minerals, eudialyte is a zircon silicate consisting of rare earth oxides (REO), contained in a unique mineral structure and represented by a complex chemical formula. Research into extraction and recovery of rare earth elements involves various beneficiation and hydrometallurgical techniques. The goal of beneficiation being to efficiently liberate and upgrade the REO content, followed by hydrometallurgy to extract the desired elements. This overview will discuss previous research on treating eudialyte group minerals via different mineral processing and extraction techniques.

By Otávio da Fonseca Martins Gomes, Renata Hiraga de Vasconcellos Cruz

Maghemite is a mineral formed from magnetite oxidation at low temperatures, an intermediate term of the magnetite-hematite series. Maghemite could be misidentified as magnetite by X-ray diffraction, and/or as hematite by spot chemical analysis. Nevertheless, non-stoichiometric magnetite was detected and quantified in samples of Brazilian soils and iron ores by the Rietveld method refinement of its structure. The results were confirmed by optical microscopy and Raman spectroscopy, thus validating the method. X-ray diffraction with the refinement of the isomorphic substitution of Fe2+ by Fe3+ along the magnetite-maghemite solid solution could help to suitably characterize maghemite in iron ores.

Oct 3, 2019

By Alberto Oalvez, Lucya Yunus, Pengfii Tan

"Laboratory flotation tests of slow cooled converter slag have showed that 92.5% copper recovery at the copper cut-off grade of 24 - 25 % can be achieved by using a 50:50 ratio of DSP330 and SIBX (sodium isobutyl xanthate) at the natural pH of 7 and with a grinding time of 18.5 minutes. 70ìéç is the P80 achieved at this grinding time. MIBC is the frother and the solid content of the flotation feed was 46%. In the plant trials, two types of collectors at two different feed particle sizes for both the normal and slow cooled slag were operated. The particle size was controlled by the feed rate. The P80 of 75 ìçé at a feed rate between 32 - 36 t/h were tested. The plant trials have demonstrated that the copper recovery in the milling and flotation process of the slow cooled slags was improved by 3%. IntroductionIt is proposed to float the slow cooled converter slag, in the auxiliary circuit of the copper concentrator at Mount Isa, by using the processing conditions identified from several laboratory flotation tests. Among these laboratory tests, one produced a copper recovery of 4 % higher than those achieved from a normal cooled slag with the same slag feed grade and the same copper content (24 - 26 %) in the concentrate. These test conditions were selected for further studies.Laboratory Test Work and Plant TrialsThere has been a lot of work conducted under laboratory and plant conditions [1]. However, the achieved results did not justify their total implementation in the Mount Isa Copper Concentrator. Initially, the lab trials were carried out with slag cooled 100% in air; then it was changed to combined cooling for 12 h with air and 2.5 days with water sprays. The reason for this change was the shortage of space when the slag was cooled 100% in air, as it takes several days to achieve safe temperatures for its removal. The San Manuel Copper Smelter has reported that their slag was left for air cooling in pits for 8 h and then was followed by water cooling for 2-3 days [2]"

Jan 1, 2012

but, returning to South Africa, for the next two years he was assistant general manager of the Simmer Deep Gold Mining Co., at Johannesburg. In June, 1911, he returned to New Zealand as general manager and consulting engineer for the Consolidated Goldfields of New Zealand, at Reefton, which position he held at the time of his admission to the 1nstitute in 1914. Early in September, 1915, he left New Zealand for active service in France. Corporal Sheppard B. Gordy Sheppard B. Gordy, born in Ansonia, Conn., in 1889, graduated from the Sheffield Scientific School in 1910 and with the degree of E. M. in 1912. He entered the employ of the Braden Copper Co. immediately on his graduation and remained with this company four years, working up through the various grades to assistant foreman and foreman to one of the individual mines. The last year he was in its employ, he acted as general mine foreman. He was for a short time with the Chile Exploration Co. and then went with the Andes Exploration Co. (Anaconda) and remained with the latter, doing mine exploration and development work, until he sailed for home in June, 1918, to give a more personal and active service to his country in her need. He declined a tender of induction into an officers' training camp, at the urgent request of Professor McClelland supplemented by Mr. Potter, because they demonstrated to his satisfaction that he could give more valuable service to his country in helping out with the aircraft production. Being within the draft age, in order to carry out this plan, it was necessary for him to be called by his Local Board and sent to camp. This call came Aug. 26. Two weeks before that time he had gone to Dayton, Ohio, to begin the study of aircraft production, and was sent by the Dayton Board to Camp Sherman, Chillicothe, Ohio, where he died of pneumonia on Oct. 9. Lieutenant Thomas Clarence Gorman Thomas C. Gorman, a lieutenant in the Second Tunnelling Company of the Canadian Engineers, was killed in France on Mar. 18, 1918. He was resting in his sleeping hut and was in the act of writing a letter when a bursting shell killed him.

Jan 1, 1920

By John A. Meech

In many multiple-sulphide ore flotation processes, it is desirable to concentrate each of the various valuable minerals into separate products. Although there are a variety of techniques and chemicals which can be employed to produce efficient separation, two basic types of flotation circuits are used: The Differential Flotation Circuit and the Bulk/Selective Flotation Circuit. Figure I depicts these two circuits in their most simplified form for the production of two concentrates and one tailing product. If three or more valuable minerals are present in an ore, a variety of combinations or extensions of these two basic flowsheets may be used. There are many examples of the successful application of both circuit types with ores containing similar minerals. Each ore must be tested individually to decide on which circuit is best. However, the following general statements can be made: 1) The differential circuit will have higher capital and operating costs than will the bulk/selective circuit due to higher rougher capacity requirement. 2) The differential circuit will achieve better separation than will the bulk/selective circuit since it is usually easier to reactivate a depressed mineral than it is to depress an already active mineral. If the deactivation problem with the bulk/selective circuit . . in can be overcome, there is a clear economic argument for its use

Jan 1, 1977

Jan 1, 2000

By Peng-Fei He

CT scanning tests were used to detect the pre-existing fracture systems of 36 cubical coal blocks. Systematic procedures were developed to construct the pre-existing fracture geometry of the cubical coal blocks from the CT images. Based on the constructed fracture systems, the fracture tensor components were calculated to capture the directional effects of the fracture system of the cubical coal blocks. The effect of the pre-existing fracture system and different combinations of confining stresses on the strength and deformability of coal masses was investigated at a preliminary level using some true triaxial test results and the computed fracture tensor components. The strength of the cubical coal blocks in the loading direction was found to be closely related to the summation of the fracture tensor components in the two perpendicular directions to the loading direction and the level of the confining stress system. The deformability of cubic coal blocks in the loading direction was found to be correlated to the fracture tensor component in the same direction.

Jan 1, 2014

By M. J. Ross, D. A. Norrgran, J. A. Wernham, J. N. Orlich

INTRODUCTION Laboratory testing for magnetic concentration circuit design is a requirement, just as it is for most other types of concentration. Natural variations in raw materials allow on1 y the broadest of generalities to be made regarding magnetic separation. Further, magnetic fields are geometry dependent, leaving fundamental models of a separator overly dependent upon the exact conditions for which the models were derived. Despite this, an understanding of the basics of magnetic separation and of the problem to be attacked can result in rapid progress towards the final circuit design with a relatively simple testing program. Magnetic Separation Basic Principles A magnetic field can readily be understood in terms of lines of flux. A familiar demonstration of these lines of flux is the pattern of iron filings on a sheet of paper when a magnet is placed underneath. Lines of flux2 are measured in Gauss (1 line/cm2) or Tesla (10000 gauss). Regions of high field strength have a greater number of lines. Field direction is indicated by a convergence of lines. When a particle is placed in a magnetic field it cuts the lines of flux and alters them in one of three basic patterns. These patterns are referred to as diamagnetic, paramagnetic and ferromagnetic. Diamagnetic materials have electronic structures which react to oppose an applied magnetic field. This opposition acts to locally reduce the applied field slightly. The visualization is that lines of flux diverge and go around the particle. Because of this divergence or opposition, a diamagnetic particle will tend to move towards regions of lower flux density. That is to say that the particle will be repelled by a magnetic field. Aluminum oxide and napthalene are examples of diamagnetic materials. Paramagnetic materials have an electronic structure which increases an applied magnetic field. Although these materials also exhibit diamagnetism, they have randomly oriented impaired electrons which align with the magnetic field. The resultant local field enhancement is significantly larger than the diamagnetic opposition. The visual-

Jan 1, 1986

By F. Brost

In 1976, a decision was made to install a conveying system to transport ore 10.3 km (6.4 miles) from the new Eisenhower Partnership Mine to Twin Buttes. The system, supplied and installed by Cable Belt Limited, of England, represents a radical departure from conventional conveyor systems. The driving tension is applied through two endless wire ropes while the belt acts only as the carrying medium. Features of the system are a single 2240 kw (3000 hp) drive and a 60° angle bend. Construction was completed in two years. Full production was attained after several months' operation.

Jan 1, 1979