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By Ning Shi

This paper suggests an alternative design approach for an innovative shovel dipper, for use in ground conditions where cutting of virgin ground rather than scooping of blasted material is required. Not only does the new design have an optimized dimension ratio (width:height:depth) and attachment arrangement (angle, position), but also a non-linear pro¯le in 2D and 3D. The approach is based on the simulation of a shovel's duty cycle to verify a pilot dipper model. In order to achieve a realistic simulation that could be used to evaluate a dipper design, the model is e®ectively a descriptor of actual shovel activity under soft ground conditions. The shovel geometry, motion and operation, with an emphasis on digging and dumping kinematics and dynamics are the principal elements of the simulation. The simulation considers a fresh face location, repeating tucking, digging and dumping swing motions within the geometric range of the machine, ending when no more face material remaining within reach without re- positioning. The simulation yields digging force, friction force, trajectory, ¯ll time, ¯ll factor, etc, which may be integrated into two basic considerations: power draw (output) and volume delivered (production), as indicators of dipper performance. The simulation has been used as a tool to modify an existing dipper design, prior to looping further simulation cycles. Ultimately, an optimized or totally-new-concept shape is realized. A prototype dipper as a fractional scale model will be built to verity the performance under actual mining conditions.

May 1, 2004

By Thomas A. Palmer

Free cyanide has been successfully determined in ground and surface water by isolation using a microdiffusion technique followed by a pyridine-barbituric acid photometric finish. The determinable free cyanide includes hydrocyanic acid, ionic cyanide, and the cyanide of weak complexes such as cadmium, lead, manganese, and zinc cyanide. Complexes of copper, iron, nickel, and silver are sufficiently strong so the dissociation into free cyanide does not occur at the microdiffusion pH 7. Cyanate, sulfide, and thiocyanate do not interfere. Samples containing as little as 0.005 mg/L are successfully analyzed. The relative standard deviation is <10%. Samples stored at pH >I2 in the dark are stable at least three weeks.

Jan 1, 1981

By Whitehead A. B

INTRODUCTIONDuring the past few years there has been considerable interest in developing the so-called direct reduction processes for treating iron oxides. The various methods proposed were recently reviewed by Scortecci and Palazzi (1960).In particular the application of fluidized bed techniques received considerable attention and, on first examination, this seems to be the ideal method &apos;of dealing with fine iron oxides. Several difficulties (e.g. product agglomeration) require the method to be investigated further before its potentialities can be fully assessed.PROPOSED FLUIDIZED BED REDUCTION PROCESSESBrassert and De Jahn (1951) were among the earliest to suggest the use of fluidized beds for the reduction of iron ore to metallic iron. Their patent was followed by many others proposing similar concepts, mainly from Lewis (1955), Ogorzaly (19.56), Shipley (1956), Agarwal (1960&apos;), Osborn (1958), Texaco Development Corporation (1956) and Stelling (1957).The H-iron process (Squires and J ohnson, 1957; Lubker and Bruland, 1960) is the only scheme that has been an economic success. This process, mentioned later, manufactures a &apos;premium quality product in the form of sized iron powder.AIM OF THE PRESENT WORKThe work reported here was performed to assist in the formulation of a comprehensive pl&apos;ogramme of research into fluidized bed reduction processes to be undertaken at the...

Jan 1, 1962

By T. Cutard, H. Marzagui, E. Ouedraogo, M. Roosefid, M. Prompt, C. Deteuf

The present work is achieved in the framework of a French national program on modeling and experimental characterization of the thermo-mechanical properties of refractory materials (PROMETHEREF). This research program is aimed to establish fair models and experimental database and to make it available to industrial partners for numerical simulation of industrial structures made of these materials. The present paper focuses on two silica-alumina refractory castables, an andalusite based one and a bauxite based one. We will present the first rheological characterization results achieved at room on normal and preheated samples of these two refractory castables. Refractory castables are characterized with the help of four points bending tests, compression tests and tensile tests.

Jan 1, 2004

By R. R. Schehl

The Bureau of Mines has developed a quantitative Analysis for pyrite in coal by X-ray diffraction that can be accomplished in little more than 1 hour. To minimize the sample analysis time, data processing has been completely computerized with pertinent output information displayed on a VR12 cathode-ray tube display. Use of this computerized system is not only advantageous during the experimental stages of the pyrite analysis project but would also be essential if the X-ray diffraction procedure is accepted as a standard method of analysis.

Jan 1, 1973

In early June, Rio Tinto?s chief executive officer Tom Albanese said that he expected demand for iron ore, aluminum and copper to double in the next 15 years. Driven by global industrialization and urbanization, Albanese said during his company?s annual general meeting that to meet the demand in 2030, the additional supply required will be equivalent to replicating the iron ore output of Australia?s Pilbara region every five years, adding another aluminum production complex the size of Canada?s Saguenay every nine months and developing another copper mine the size of Escondida, in Chile, each year.

Jan 1, 2010

By Conny Sjoberg, Finn Ouchterlony, Bjorn Jonsson

This contribution reports an investigation of the blasting damage in the contour of an access ramp to a Swedish underground laboratory for nuclear waste related studies. Near zone vibration measurements were made for 7 rounds and the results converted to a site specific scaling law. A simple engineering correction for the influence of the charge length wee developed and the resulting equations used to predict the damage zone depths of three different drilling and charging patterns.

Jan 1, 1993

By Rita D. Sylvester

"IntroductionThe Bureau of Mines was established in the public interest to conduct inquiries and scientific and technologic investigations concerning mining and the preparation, treatment, and utilization of mineral substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increase efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting these industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the Bureau to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, the Bureau reports the findings of its research and investigations in its own series of publications and also in articles that appear in scientific, technical, and trade journals; in proceedings of conventions and seminars; in reference books; and in other non-Bureau publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make the kind of list and index presented in this special publication both necessary and valuable. This issue describes reports and articles published during the period January I, 1965, to December 31, 1969. It supplements the 50-year list of Bureau publications issued from July 1, 1910, to January I, 1960;' the 50-year list of articles by Bureau authors published outside the Bureau from July 1, 1910, to January I, 1960;3 the 5-year list of Bureau publications and articles from January I, 1960, to December 31, 1964.' It includes all the material in the four annual lists of Bureau publications and articles from January 1, 1965, to December 31, 1968, as well as the Bureau publications and articles for 1969."

Jan 1, 1970

By Hadyn W. J. Wren

The practical experience obtained from designing and commissioning of fully controlled coal preparation plants, using centralised mini computers is discussed. The importance of defining a workable operating philosophy is highlighted with particular reference to the problems associated with trying to achieve a total &apos;hands off&apos; concept. These experiences with a centralised computer controlled system have led to a deeper understanding of the interaction between the operation and the control system and the role of local control and management information within the overall control philosophy of a highly automated process plant. The utilisation of an extensive fully distributed microprocessor control system with over 6500 digital and analogue signals split into six autonomous areas with a supervisory system to provide operator interface is described. The important aspects of project definition and design needs are outlined with particular regard for achieving maximum efficiency with minimum complexity. Views of future trends are offered, based on the experience of both centralised computer and distributed processor systems.

Jan 1, 1984

By Robert B. Fulton

Staurolite, an iron aluminum silicate mineral, is used industrially as the source of aluminum in portland cement manufacture in areas where the aluminum constituent is not economically available from shale or argillaceous limestone. It is also used as a high value- in-use sand blasting agent and as a premium grade foundry sand. It is produced by E. I. du Pont de Nemours & CO. as a coproduct in titanium mineral production in Florida where it was first recovered on a commercial scale in June 1952 from the Pleistocene sand deposit known as Trail Ridge. In the Trail Ridge deposit it comprises about 36 of the heavy minerals, the principal other heavy mineral constituents being ilmenite, leucoxene, rutile, zircon, kyanite, sillimanite, and tourmaline. Staurolite and the other silicate nonconductive heavy minerals are separated from the conductive titanium minerals on high-tension separators. The silicates are then separated from one another magnetically, the staurolite being relatively magnetic. In the total processing, 200 tons of raw sand yield 7 tons of heavy mineral concentrate from which about one ton of staurolite is recovered. Staurolite production is approximately 100,000 net tpy. No other commercial production of staurolite is known. This process yields staurolite concentrates of the characteristics given in [Table 1]. These concentrates are sold as three products with the size distribution of subrounded particles shown in Table 2. All three grades are used in sand-blasting for cleaning metal, for paint removal, and for cleaning buildings. Staurolite compares favorably with lower unit cost abrasives, such as boiler slags and mineral aggregates, in applications where the abrasive is used only one time and is not recovered. Because it is hard, fine, clean, and dense it can reduce blasting time, with less material reportedly being required

Jan 1, 1975

By Hassan El-Shall

Treatment of plant effluent including waste water and associated soluble and insoluble substances, is of a primary concern of many process industries including mineral processing operations. The major objective of such treatment is the removal of such impurities which can interfere with the process through the use of recycled water, and/or to comply with environmental ordinances. For example, Ramirez and Clements (1978) state that molybdenum contents in the range of 19 mg/1 eventually poison ion exchange resigns used for the extraction of uranium. In addition, recent restrictions by the EPA on molybdenum discharge values for mining waste water necessitate removal of this metal to (0.5-1.0 mg/1).

Jan 1, 1984

By Gary Raymond

The Similkameen Division of Newmont Mines Limited operates a low-grade open-pit copper mine in southern British Columbia. The copper mineralization is extremely erratic.As a result, over seven years of operation, ore control methods have evolved from standard flagging based on blast-hole assays, through an in-pit grab sampling system, to the present method of mining to computer-determined ore-waste boundaries based on geostatistics. These improved ore control methods have resulted in a gain of at least 25% on ore tonnage miffed, at the same grade as obtained using earlier techniques. At the same time, geostatistical ore reserve estimates are now within 7% of milled ore tonnage and grade on a yearly basis, whereas the original polygon ore reserves under-estimated mineable ore tonnage by 15% to 45% and over-estimated grade by about 20%. The author discusses why traditional ore estimation methods give poor results in erratically mineralized orebodies and describes the geostatistical approach to the problem.

Jan 1, 1979

By R. W. Raymond

The Mining Law of New Pork, contained in Title XI., Chapter IX., Part One of the Revised Statutes, is as follows: Section 1. The following mines are, and shall be, the property of the people of this State in their right of sovereignty : (1.) All mines of gold and silver discovered, or hereafter to be discovered, within this State. (2.) All mines of other metals discovered, or hereafter to be discovered, upon any lands owned by persons not being citizens of any of the United States. (3.) All mines of other metals discovered, or hereafter to be discovered, upon lands owned by a citizen of any of the United States, the ore of which, upon an average, shall contain less than two equal third parts in value of copper, tin, iron, and lead, or any of those metals. Sec. 2. All mines and all minerals and fossils discovered, or hereafter to be discovered, upon any lands belonging to the people of this State, are, and shall be, the property of the people, subject to the provisions hereinafter made to encourage the discovery thereof. Sec. 3. All mines of whatever description, other than mines of gold and silver, discovered, or hereafter to be discovered, upon any lands owned by a citizen of any of the United States, the ore of which, upon an average, shall contain two equal third parts or more, in value, of copper, tin, iron, and lead, or any of those metals, shall belong to the owner of such land. Sec. 4. Every person who shall make a discovery of any mine of gold or silver within this State, and the executors, administrators, or assigns of such persons, shall be exempted from paying to the people of this State any part of the ore, produce or profit of such mine for the term of twenty-one years, to be computed from the time of giving notice of such discovery, in the manner hereinafter directed. Sec. 5. No person discovering a mine of gold or silver within this State shall work the same until he gives notice thereof, by information in writing to the Secre-

Jan 1, 1888

By C. Vasquez, A. Nieto

In past drilling programs for a multi-seam Texas lignite reserve, extensive e-log data was collected; however, little laboratory analyses were performed. As a cost and time saving incentive, sampling of lignite was intensified. In a recent drilling program in east-central Texas, detailed laboratory analyses and e-log information was gathered on a multi-seam lignite reserve of the upper Wilcox Group. This data will undergo statistical and geostatistical techniques in an attempt to discern whether or not predicted Ash and Btu/lb values can be derived from the e-log gamma-density relationships. Final characterization of the dataset will be used in a geostatistical model of that reserve. This model will be the basis for further geological investigations and mine planning.

Jan 1, 2004

By A. Werenfels

After discussing the geology of the Limagne, the surface indications of petroleum, and the recent exploration, the author states that none of the wells were properly located and that oil possibilities of the Limagne have not been adequately tested. NO PETROLEUM, in commercial quantities, is found in France except the small production of the Pechelbronn field (Fig. 1) in Alsace, which produced 75,000 tons in 1923; therefore the test of the petroleum FIG. 1.-KEY MAP. prospects of the Limagne is most interesting. Under the superintendence of M. Termier, chief engineer of the French mines, a well near Crouelle (Fig. 2) was drilled in 1921 to a depth of 856.3 m. (2808 ft.); at different depths favorable showings were encountered. The well, however, was abandoned because of drilling difficulties. A second one is now being drilled near the same place.

Jan 12, 1924

Natural gas from the south west Queensland gas fields is now available in north west Queensland to fuel the development of many Carpentaria Mineral Province projects. Like these projects, the south west Queensland gas project, developed under the operatorship of Santos Ltd, has its own æMining CycleÆ. While the project is entering its third expansion phase, it is at the same time actively extending its discovery phase, with large programs of gas exploration and reserves definition. This paper outlines the history of the south west Queensland gas project, with particular emphasis on the relationship of the project to north west Queensland.

Jan 1, 1998

During 1979 the writer had the privilege of interviewing about 50 people with varying degrees of involvement in the industrial arena and all of them in one way and another, had a part to play in the huge and intricate saga of Australian employee relations. They fell into the following&apos; categories Industrial Relations Officers/Managers Academics Politicians Union Officials Representatives of Employer Associations Senior Industrialists Commission Members (State and Federal) Sundry (Journalists, Government Officials). This paper seeks to give an account of their views on various aspects of industrial relations. The interviews conducted were all on a personal and confidential basis so it can be expected that sources will not be identified. Suffice it to say that this account represents, albeit in "potted" form, the opinions of some of the most experienced individuals in the country. It will be seen that in most of the vital areas there is a remarkable lack of consensus. It should be noted that this lack of consensus existed within each of the groups mentioned.

Jan 1, 1980

By Ping K. Di

A naturally aged and synthesized manganese oxide-coated granular media was found in our laboratory to have the capability of the removal of soluble Mn(H) from mine drainage by adsorption and oxidation. Mine drainage commonly also includes other heavy metal ions. Extending this principle, this paper presents the removal of heavy metals including lead, copper, cobalt, zinc and nickel in the aqueous solution by using the synthesized manganese oxide-coated granular media. It was found that the adsorption of lead, copper, cobalt, zinc and nickel on the manganese oxide-coated media follows both Langmuir and Dubinin-Radushkevich adsorption isotherms except in the concentration range less than 0.1 mmole/L. The adsorption mechanism involves the ion exchange between the heavy metal ions and synthesized manganese oxide coated on the media. The synthetic manganese oxide surface has a strong metal binding ability to the heavy metals in the order of Pb2+ > Cu2+ > Ni2+ > Zn2+ > C02+ based on the adsorption results using batch and continuous column operations. The breakthrough curves of these heavy metals showed that the synthesized media could be used effectively in the removal of these heavy metal ions in a cell or packed column. The process can simultaneously facilitate the immobilization of the heavy metals on the synthesized manganese oxide coated media. A subsequent pH adjustment dislodges the heavy metals and regenerates the synthetic media. Thus, the process accomplishes the adsorption, immobilization and concentration of the heavy metal from waste stream in one monolithic procedure.

Jan 1, 1995

By Peter Heine

Diavik Diamond Mines Inc. (DDMI) has treated systems development as an integral part of the construction project when it built Canada?s second diamond mine. Fully aware that the proper collection and processing of operational data is needed to drive business decisions during production and planning, key Performance Indicators (KPIs) were defined to effectively manage operations when the mine went into production. The Production Information Management System (PIMS) allows KPIs to be measured, reported, and transferred to other systems in a reliable and convenient manner. PIMS provides a mechanism to collect real time production data from the various control systems around the site and acts as a tool to ?drill-down? and establish the important cause-effect relationships that impact the value of a KPI. Thus PIMS provides a data collection, storage, management, and an environment in which cause-effect relationships can be analysed and statistically verified. This understanding of the real cause-effect relationships, close to the source of the data and in the context of the operation, can be used to improve both operations and maintenance performance. The PIMS includes the PI Database implementation, its associated external interfaces with the various Control Systems, Cleaning Packaging Weighing System, Environmental System, Enterprise Asset Management (EAM) System, and Diamond Tracking System (DTS), as well as laboratory data collection, custom applications (downtime tracking, data reconciliation) and user clients. The interface with the EAM system provides material flow quantities and equipment availability on which the plant performance reports are based. The transfer of equipment usage to the EAM system is fed into the maintenance notifications and work orders functionality in the EAM. The environmental system interface provides the mechanism for capturing water consumption data required to generate the various regulatory reports. The interface to the cleaning-packaging-weighing system provides the mechanism for capturing batch data for transfer to the DTS for diamond product tracking at the production splitting facility in Yellowknife. The PIMS lab application provides a means of getting sample data into the system for critical metallurgical metrics, and the data reconciliation application provides a means of manually verifying the data before it is published or passed onto other systems.

May 1, 2003

By S. -H. Jeon, Y. -S. Choi

"The three dimensional current distribution on the rectangular cathode is predicted using a boundary element method with a linear element of trigonal type. The effect of cell geometry and anode shape on current distribution is simulated. Calculated results compare well with experimental results. The proper combination of anode size and distance between electrodes increase the current uniformity.The importance of electrodeposition as a fabrication technology in the electronics industry is large and growing. The main advantages of this wet processing method, in comparison to other dry processing methods, lie in its high yield, rapid processing and low cost. In nearly every application of electrodeposition the pursuit of deposit uniformity, especially thickness uniformity, has been technically imperative. The thickness uniformity of the deposit depends largely on the current distribution over the cathode. The current distribution is primarily determined by the geometrical characteristics of the electrodes and the cell. Also the polarization at the electrode surface and the mass transfer affect the current distribution.The current distribution is an important consideration for those involved in designing electrochemical systems and electroplating systems in particular. Although it is important, the common practice in industry is to use trial and error method to design the cell that optimize the uniformity of current distributions in electroplating. The purpose of this paper is to illustrate the useof boundary element method to predict three-dimensional current distribution in rectangular cell.The calculation of the current distribution is possible by various numerical techniques, which include the finite difference method (FDM)1, the finite element method (FEM)2, and the boundary element method (BEM)3,4. These methods of the numerical calculation have various problems, respectively, but the BEM is considered to be the most efficient. This is due to the fact that the BEM has the advantage of solving field equations only on the surface of a calculation domain. A good comparison between the BEM and the FEM for the secondary current distribution in a Hull cell was made by Matlosz et al.5The fundamentals on the theory of current distribution in electroplating are well-established in the literature by a number of authors.6, 7, 8 However, a small fraction of these works have been specially addressed to three-dimensional analysis, and, mostly thel·10 have focused on the problem qualitatively rather than quantitatively.Extending the previous work to three-dimension, we developed the program for the quantitative calculation of 3-dimensional current distribution using a boundary element method with a linear element of trigonal type. Integrals with singularity from the fundamental solution have been analytically computed and it is shown in detail in the Iiterature11. This paper deals with the three dimensional current distribution for the electrode position of copper in a cubic type cell and the effect of anode shape, size and the distance between electrodes on current distribution is studied."

Jan 1, 1997