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By P. M. Brown

The Bureau of Mines is investigating a dewatering technique for coal-clay waste that uses a flocculant, polyethylene oxide (PEO). This flocculant forms strong stable flocs that can be dewatered on a static screen. A field test unit (FTU) using this technique was operated at approximately 400 gal/min, using a waste stream from the flotation circuit of a coal preparation plant. Consolidated coal-clay material con-taining 55 to 60 pct solids was produced when the flotation circuit slurries of 2.7 to 8 pct solids were treated with 0.1 to 0.3 Ib PEO per ton of solids. The FTU was also operated at 64.5 and 87.5 gal/min using a portion of the underflow slurry from the preparation plant's thickener. Consolidated coal-clay material containing 55 to 60 pct solids was produced when the thickener underflow slurries of 19 to 24 pct solids were treated with 0.08 to 0.2 Ib PEO per ton of solids. PED-treated materials continued to dewater when placed in a pit.

Jan 1, 1983

By E. R. Drevdahl

It has been suggested that we at the University of Arizona present a paper covering the origin, philosophy, and results of the College of Mines program in the field of computers and operations research. I have worked with the program since its beginning, and I will try to outline the developments as they have taken place. The formal development of the educational and research program in the field of Operations Research and Computer Applications at the College of Mines, University of Arizona, began in early 1957. During the year, the University offered its first formal instruction in computer programming. This was my first introduction to computers, and it did not take long to realize that this new tool had a potential that could be profitably utilized by the mining industry. In March 6f 1957, the University Computing Center began operations with its IBM 650 computer. This machine was the only computer of this size in the local area at this time, The first programming effort was in machine language and the programming cost could only be justified for repetitive-type of problems. The progress in the computer field moved very rapidly and with the development of the many compiler and assembly programs and the addition of sub routines to the computer library, the scope of problems that could profitably be investigated by computers expanded rapidly.

Jan 1, 1963

By A. G. Oppegaard

Most iron ores treated by the R-N direct reduction process yield metallic iron products considerably lower in titanium, manganese, and chromium oxides and alkaline metal sulfates/sulfides than were contained in the original ores. These metallic iron products are suitable as feed stock for the open hearth and electric steel-making furnaces. The elements which are rejected in part are acceptable in the product since the product is designed to by-pass the blast furnace. R-N reduction conditions (PCO+H2-1 atmosphere, 1830° to 2150° F.) are adjusted for each ore. The iron ore which is reduced to 90 to 95 percent metallic iron is then subjected to the conventional beneficiation techniques. Under these conditions, 55 to 80 percent of titanium oxides, 75 to 95 percent of manganese oxides, 60 to 90 percent of chromium oxides and up to 97 percent of alkaline metal sulfates contained in the ore are rejected with the gangue to the non- magnetic tailings. The metallic iron products illustrated in this work contained 89 to 96 percent total iron, one to five percent TiO2, 0.2 to one percent MnO, 0.3 to 1.6 percent Cr2O3 and/or up to one percent alkaline metal sulfide. Usually only one of these components was present. Recoveries ranged from 80 to 96 percent of the iron in ore.

Jan 1, 1958

By R. D. Leitch

Beside many other damaging effects of acid mine drainage, corrosion of pipe lines and pumps frequently adds much to mine operating, costs. Not only is it often necessary to install special and relatively costly acid-resistant materials, but even these may require frequent replacements. It is not unusual for ordinary steel pipe to last only a few days in some highly acid waters, while other common materials, though more resistant, frequently cast only a few weeks. In the spring of 1935, local PWA authorities offered to assign a number of persons to various problems under the direction of regular employees of the Bureau of Mines. It was believed that at least some simple tests on as many different kinds of acid-resistant pipes as could readily be obtained might produce interesting; and valuable information for the mining industry. This paper describes the tests and some results that have since been noted.

Jan 1, 1938

By G. Unland

The sizing of crushers depends on the expected crushing forces. However, the crushing forces develop differently with every individual rock while it is compressed by the working surfaces of the crusher. For sizing, this compression process has to be characterized by the maximum crushing force. The maximum crushing force depends on the strength, shape and size of the rock, the amount and velocity of the imposed displacement of the working surfaces of the crusher on the rock and the conditions of the contact surfaces. From experience it is known that the strength of the material and, therefore, the crushing forces depend on the size of the specimen. This dependence is the so called size effect. The determination is based on compression tests. The force development is recorded during the compression of the specimen and for every individual test the maximum force is determined. The occurring maximum crushing forces of several rocks with the same diameter comminuted under the same conditions can be assessed by a mean value and a variance. The relationship between the mean values of the cross section related maximum crushing forces FAmax and the corresponding sizes d of the specimens can then be described by mathematical functions. They are derived from different approaches (phenomenological, statistical and statistical-physical methods). The phenomenological methods are subjective and yield functions depending on the assumptions of a person, whereas the statistical and statistical-physical methods are based on an evaluated function and the optimization of the parameters.

Jan 1, 2014

By R. Merkl

Since the 1940s, decanter centrifuges have become more important for increasingly complex solid-liquid or solid-liquid-liquid separation processes. Sometimes processed industrial or metalliferous minerals are abrasive or are treated with corrosive chemical agents. Traditional mining applications include the processing of coal, gravel and other products, where low-speed decanters, as well as screen bowl decanters and filters, dominate. These have been increasingly replaced by high-speed decanters during the last decade. Decanter centrifuges also started to play a key role in applications such as drilling muds, processing carbonates and separating SX crud in copper platinum ore concentrations of nickel and gold. Communication between machine producers and mineral processing engineers is vital for the right choice of materials and the design of the right decanter centrifuge for the individual process.

Feb 1, 2012

By Tom Gaines, G. S. Brant, J. G. Debanne

"AbstractThe Bonnie Glen oil field, one of Canada's largest, lies about fifty miles southwest of Edmonton, Alberta. One hundred and thirty-eight wells have been completed in this field since its discovery in January, 1952. Five different procedures have been used in completing the producing wells.The reservoir is an Upper Devonian biohermal reef with good porosity and uniformly high permeability. The top of the reef is quite flat but the flanks slope at angles approaching 20 degrees from the horizontal. The reservoir has a gas cap with a maximum thickness of 400 feet, an oil column of 300 feet, and a :porcus aquifer of over 300 feet. The reservoir pressure is now 2,400 pounds per square inch gauge at datum ( -4100 M.S.L.).Because of the high permeability and the high •pressure, lost circulation and resultant blowouts are a particular hazard in drilling at Bonnie :Glen field. To reduce the dangers of blowouts, it is general practice to run casing to the top of the reef. If the reef is encountered 'high' it was usual practice to run a liner and perforate for completion. Wells penetrating the •reef below the gas/oil interface were either completed in open hole or through casing perforated opposite the oil pay, with the former method more frequently used. Eight wells were completed by the Humble-Otis permanent-type completion, and recently five high wells were completed open hole with the gas •cap exposed. This latter completion, 'tubing submergence', has proved highly satisfactory thus far.The open-hole type of completion is cheaper than the liner perforation method and results in better well performance. More experimentation and data are needed before the tubing submergence method can be recommended unqualifiedly. but all evidence thus far favours its use in reef reservoirs."

Jan 1, 1955

By A. W. Deurbrouck

This report presents the results of a washability study of 322 coal mine samples showing the sulfur forms and distribution in the coals. The samples were collected from mines which were principally utility coal producers. Generally, the data show the total sulfur content of the coals evaluated could be significantly reduced by some combination of stage crushing and specific gravity separation. However, few coals could be upgraded to a final product containing 1 percent or less total sulfur. The complete washability data are presented for each sample processed. A statistical evaluation is included for the coalbeds from which more than 10 samples were collected and for the geographical coal producing regions. A graphical summation is presented for the coal producing regions and selected coalbeds.

Jan 1, 1972

By Maurice Allais

El presente texto señala la importancia de la investigación en la formación económica del ingeniero donde el cálculo económico es la base de la enseñanza de las grandes escuelas. En este sentido, es importante conocer la teoría de los óptimos económicos, la teoría del rendimiento social o teoría de la eficiencia. Asimismo, debe mostrarse el significado del precio, los cálculos de rentabilidad, la teoría del riesgo (probabilidad) y las decisiones que incluyan elementos aleatorios.

Mar 1, 1971

By Michael M. Kimberley

Stratiform uranium deposits occur in Canada along the north shore of Lake Huron near the base of the Middle Precambrian Huronian Supergroup. Outcrop of the Buronian Supergroup extends for over 400 km from Sault Ste. Marie in the west eastward through Sudbury and then northeastward to Cobalt. Maximum stratigraphic thickness exceeds 5 km. The predominant Huronian rock type is metamorphosed sandstone (quartzite), with sub- ordinate argillite, conglomerate, mixtite (possibly tillite), volcanic rocks, and minor limestone, Much of the quartzite is highly feldspathic. Substantial uranium ore was first discovered in Huronian rocks in 1953 and has been exploited continuously since the initial mine-mill plant was constructed at the Pronto ore body, 30 km south of the present townsite of Elliot Lake. Only one ore body remains in production, however. It is shared by Rio Algom and Denison Mines 14 km north of the town of Elliot Lake.

Jan 1, 1980

By Marek Dworzanowski

Dense medium separation (DMS) is critical to the operation of coal and diamond beneficiation plants. It is also utilised in iron ore, manganese, chromite and andalusite beneficiation as well as pre-concentration for platinum-bearing UG2 ore. Gravity concentration plays an important role in the processing of diamonds, coal, gold, platinum, titanium minerals, zircon, chromite, iron ore and manganese. The DMS and Gravity Concentration operations and technology in South Africa conference will focus on the operation of DMS and Gravity Concentration circuits in the South African Mining Industry. The current status of the technologies and equipment employed will be presented as well as future developments. The conference was set up to showcase South African DMS and Gravity Concentration operations and provide a forum where operators, technology and equipment suppliers can engage in knowledge sharing. The papers cover a wide spectrum of topics, including descriptions of operations, optimisation projects, new capital projects, equipment applications, process monitoring and process selection. Most commodities and unit processes associated with DMS and Gravity Concentration are covered. The conference venue was selected to be the CSIR Convention Centre in Pretoria. The CSIR has contributed to DMS research in South Africa and it is located not far from many coal, diamond, gold, platinum and chrome mines that extensively utilise DMS and Gravity Concentration in their beneficiation plants. I believe that the papers and presentations submitted for this conference will provide a valuable future reference for DMS and Gravity Concentration, thus making the work of all the contributors to this conference highly rewarding and worthwhile.

Jan 1, 2006

By A. P. Paiva

The solvent extraction properties exhibited by some /V,N'-tetrasubstituted malonamides to efficiently and selectively recover iron(III) from concentrated chloride leaching solutions can be found in the recent literature. The iron(III) extractive chemistry exhibited by some of these derivatives is revisited, in order to compare their chemistry with that shown by a few of the new malonamide compounds. The generally good extraction efficiency towards Fe(III), from >4 M hydrochloric acid solutions, and the relative ease of Fe(III) stripping by distilled water are remarkable findings that are confirmed for the malonamide derivatives described in this work. Furthermore, additional data regarding their selectivity towards Fe(III) extraction over several base metal ions and their behavior when subjected to successive Fe(III) extraction-stripping tests are also presented and discussed.

Jan 1, 2006

By Ludwig Schmidt

The attention of operators of oil-producing properties long has been directed toward methods of' disposing of petroleum wastes as well as the disposal of oil-field brines. The problem of disposing of' petroleum wastes is not easy to solve, and although many operators are to be commended for the efforts they have made, much work remains to be done before the problem can be considered solved. Petroleum wastes include emulsions of petroleum and brine or mixtures of petroleum and sand that cannot be "broken down" or treated economically by known methods of separating petroleum from deleterious matter; crude petroleum that escapes from pipe lines, fittings, and tanks because of holes in the lines, leaky connections, or some accident; and oil-saturated materials that accumulate accidentally or otherwise an the normal operation of an oil-producing property.

Jan 1, 1938

By E. J. Sullivan

This study seeks to define the mechanism of oxyanion sorption onto surfactant-modified zeolites. Zeolites which have been treated with hexadecyltrimethylammonium bromide (HDTMA) surfactant to produce a hydrophobic surface are capable of sorbing both organic compounds as well as oxyanions such as chromate, selenate, and sulfate. Simple ion exchange and charge-balancing mechanisms do not fully explain this unusual phenomenon. The sorption of HDTMA surfactant appears to be partly ion exchange and partly sorption to non-ion-exchangeable sites. Sorption of chromate is a simple exchange mechanism with bromide, which co-adsorbs with HDTMA to form a surface precipitate. Information from this study will be used to design on-site and in situ treatment systems for contaminated water, such as filter beds and permeable barriers.

Jan 1, 1995

By Alan J. Solomon

The function of advertising is communication. Viewing the advertisements of mineral suppliers exposes the reader to a broad spectrum of purposes: announcements of new products, availability and supply, departmental services, company image, etc. It is the advertiser's hope that the message being conveyed is the same message being perceived by the viewer. To maximize this probability, the advertiser at least must carefully construct precise copy, identify the target audience and select the appropriate advertising medium. A truly successful and efficient ad, however, also must accurately reflect a product's life cycle, i.e., the rise and fall in demand for a product. Buggy whips and radio tubes are classic examples of items formerly in high demand. Industrial minerals are similarly affected by occurrences of product life cycles.

Jan 1, 1983

By Stanley C. Suboleski

The increase in productivity which has been achieved in mining during the past two decades has been attained largely through the replacement of manpower with electrical power. Power demands should continue to increase, requiring electrical distribution systems to be well planned to avoid inadequate voltage levels caused by underdesign and excessive costs resulting from overdesign. To aid the mining electrical engineer in designing proposed power systems or analyzing changes to existing systems, a digital computer program has been developed. This program will analyze alternating or direct-current networks with up to 10 voltage sources, 75 loads and 300 total segments. A maximum of nine levels of voltage is permitted in the system. This project was part of a package of programs developed at Virginia Polytechnic Institute (WI) for the mining industry under sponsorship of the Office of Coal Research. Included in this package are also programs to: 1. Schedule mine production and predict cost of mining 2. Simulate rail haulage systems 3. Simulate belt haulage systems 4. Analyze ventilation networks 5. Analyze pumping networks These programs are available from the Department of Mining Engineering, VPI, Blacksburg, Virginia 24061 for a nominal processing cost.

Jan 1, 1970

By W. H. Eddy

The Bureau of Mines made small-scale continuous tests and large-scale commercial plant tests of a calcareous fluorspar ore near Cave-In-Rock, Ill., to determine if the application of the lignin-fluoride process of fluorspar flotation would be industrially feasible for treatment of fluorspar ores, and also to compare the lignin-fluoride process with the quebracho process, which is the method currently used for concentrating calcareous fluorspar ores. The small-scale continuous tests yielded fluorspar concentrates analyzing 93.6 percent CaF2 with a recovery of 87.6 percent of the total fluorspar in the ore. In large-scale commercial plant tests, a fluorspar concentrate analyzing 93.3 percent CaF2 with a recovery of 78.0 percent was produced by the quebracho method. About 86.0 percent of the fluorspar was recovered in a metallurgical-grade fluorspar concentrate from the lignin-fluoride circuit which analyzed 89.9 percent CaF2? with a much simpler flowsheet than that in the current commercial application.

Jan 1, 1967

By T. Kimura, H. Ohba

"Much effort has been made to reduce the energy requirement in zinc electrowinning. In order to keep energy consumption low, either to make cell voltage low or current .efficiency high is necessary. Decrease of cell voltage practically depends on how to reduce ohmic resistance in the electrolyte and the anode crust. To realize these, new concept was proposed and the pilot plant has been operated. The space between a cathode and an anode is halved by utilizing the frame insulator. With these frames the anodes and cathodes compose of a unit of electrodes, and this unit is handled by newly designed electrode handling machine (E.H.M.). The process includes lifting up electrodes, expanding the space between a cathode and an anode, cleaning them, stripping the deposited zinc and returning the unit to the cell. As a result, cell voltage is kept as low as calculated and predictable energy reduction has been achieved. IntroductionIn the recent trend of a rapid appreciation of the Japanese yen, Akita Zinc Refinery of Mitsubishi Metal Corporation has been confronted by problems of relatively high operating costs. In order to compete with other overseas zinc refineries, it is necessary to reduce the cost of zinc production, especially the cost of electric power which now accounts for .up to 35 % of the entire cost of production. Three fourth of the electric power used at Akita Zinc Refinery is for the electrolysis. Therefore it is extremely important to reduce the cost of electrolysis.There are two possible measures for solving the problem; one is to use more nighttime electricity taking the advantage of its inexpensive power price, and the other is to reduce electric power consumption.As a part of a rationalization plan carried out in 1986, Akita Zinc Refinery increased the number of operating cells. As a result, when nighttime electricity is used, the silicone rectifier has been able to operate at full capacity. Moreover, by new schemes of ""increase of area for electrodeposition by ralslng the liquid level of electrolyte"" and ""increase of the number of electrodes in each cell"", current density could be lowered and as a result, the electric power consumption has been improved. In order to raise nighttime ratio even higher, installation of an additional rectifier and cells would be required."

Jan 1, 1988

By Jason Mewis

Do you have it figured out? ? If so, I want to network with you! ? There?s a lot to learn as an industry The more we share the better we?ll all become at dealing with this subject If you don?t have it figured out ? You?re among the majority in the in0dustry ? Project Risk is a broad and complex issue that is dealt with through many processes ? And it?s not intuitive either ? And you don?t want to confuse one process with Another

Nov 1, 2011

By Tom Setterfield

Conclusions ?Canada is a prospective place to explore for IOCG deposits ?Time distribution of IOCG mineralization in Canada mimics that in the rest of the world ?Canada may have been the first country to start mining IOCG deposits ?Production from newly discovered IOCG deposits in Canada may start soon

May 1, 2006