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By William G. Schultz

Sylvite of Canada, a division of Hudson Bay Mining and Smelting Co., operates a new 8500-tpd potash mine ten miles northeast of Rocanville, Sask. This mine, employing less than 60 men in its underground maintenance, engineering, and production operations probably ranks as one of the most highly mechanized and automated mining operations in the world. Access to the flat lying potash bed is through two 16-ft-diam concrete and steel lined shafts 3300 ft deep. The backbone of the operation is two 258-ton, 1500-hp continuous mining machines capable of mining in excess of 700 tph per machine while employing extensible conveyors for haulage. This production capability is complemented by a completely automated haulage, storage, and hoisting system. Of the other unique features of this operation, the principal ones are that the mine was designed and developed by the people that are currently operating it and from the time the shafts were commissioned, the mine was completely developed, equipped, and brought to full production in less than six months.

Jan 1, 1974

By P. R. A. Andrews

"The sillimanite group minerals, kyanite, sillimanite and andalusite are identified as alumino-silicate minerals with the common chemical composition AIP3.Si02' so that each possesses similar physical properties. Kyanite is the most abundant mineral and mainly occurs in Quebec, Ontario and British Columbia; sillimanite occurs in Ontario and Manitoba; and andalusite in Nova Scotia. The main use for the sillimanite-group minerals is in refractory applications for the production of refractory bricks and shapes. In refractory applications, the main performance criterion is the relative percentage of mullite formed within the material during firing. This phase gives a greater degree of resistance to creep deformation and slag attack, and improves the ability of the refractory to withstand high temperatures under load. The beneficiation of refractory silicate minerals has been the subject of many investigations at CANMET, and the former Mines Branch. Eighteen kyanite, two sillimanite, and three andalusite evaluation studies were conducted between 1933 and 1987. A review of some of the more important studies is presented, which includes information concerning mineralogy, beneficiation methods and flotation data."

Jan 1, 1995

By Charles M. Cooley

In these troubled times free enterprise is maintaining vital molybdenum output, while expanding plant, and bringing in new low grade ore reserves, at Climax, the world's largest known molybdenum deposit. Climax Molybdenum Co. is putting $25 million into additional surface plant facilities and other millions into underground development. The expansion program to be operating by 1954 includes a new mining level, crushing plant, 4000-ft conveyor, milling units, by-products plant, and housing for 198 families. Completion of this program and low grade plant will add 10,000 tons per day to present capacity and several million tons to ore reserves.

Jan 1, 1953

By Kazuyo Yokoyama

New environmental assessment model based on the Waste Input-Output analysis has been developed and applied for the "Landfill mining activity". "Landfill mining" implies the digging up of the landfilled wastes, the recovery of valuable material and energy resources and, thus, the reuse of the saved space as a new landfill site. In this study, the landfilled wastes are assumed to be treated by the gasification/melting processes. Two kinds of reactors, the fluidized bed type (FB) and the shaft furnace type (SF), have been considered in this work as the typical gasification/melting processes adopted in Japan. In FB, the dug-up wastes are heated in the sand fluidized bed zone under reducing atmosphere, Fe and Al are recovered in the metallic form, and then, the gasification/melting of residues is made in the second zone. In SF, the waste is charged in the high temperature coke bed, and the gas is recovered together with molten metal and slag. Both processes generate electric power by the recovered heat and fly ash as waste to landfill. It has been found in this study that the both processes can reduce the total volume of waste and save the available landfill space. SF seems to have higher potential for decreasing volume of wastes because of less emission than FB while FB has great benefit to recover metallic Fe and Al individually. The results of scenario analysis have also indicated that the landfill mining activity is effective for sustainable management of landfill sites.

Jan 1, 2006

By J. W. Axelson

CRUSHING has always been a major operation in the chemical and metallurgical industries, yet little is known about the theory of crushing, and today, the design of crushers is still based almost entirely on empirical knowledge and accumulated practical experience. In view of the increasing national need for the economic working of poorer grades of ores, the lack of a fundamental under- standing of this unit operation hardly presents a satisfactory situation. Basic investigations of crushing have been concerned mainly with three phases of the problem, 1-the mechanism of the fracture process itself, 2- the particle size distribution of the crushed product, and 3-the relationship between the energy input and the amount of new surface produced. Probably adequate information on these phases will be required for a comprehensive understanding of the process of crushing. A bibliography covering these phases will be given as well as a review of the work done in recent years at the University of Minnesota on the relationship between the energy input for crushing and the amount of new surface produced.

Jan 12, 1951

By Arthur W. Griffith

Ozark Lead Company, a wholly owned subsidiary of Kennecott Copper Corporation, was formed in 1961 to operate in the State of Missouri. The orebody presently being mined was discovered in January of 1962, and over a quarter of a million feet of drilling was done to determine its value and extent. In addition, a development shaft, six feet in finished diameter, was drilled into the orebody by an oil field rig in order to support the results of the core drill samples and to obtain bulk samples of ore for metallurgical pilot plant testing, upon the results of which the primary flowsheet was established. The design criteria developed from the flowsheet was based upon a 6000 TPD plant throughput and the subsequent engineering and construction of the mine and concentrating plant was completed in June 1968. The plant, which is designed to mine and mill 6000 tons of ore per day and produce 60,000 tons of lead and 8000 tons of zinc in concentrate annually, is located approximately 110 air miles south- west of Saint Louis. MINERALOGY The orebody occurs in the Bonneterre dolomitic limestone formation in the form of irregular masses of disseminated sulphides in essentially horizontal beds. The Lamotte sandstone underlies the Bonneterre formation and is barren in values. Principal ore minerals include galena with lesser amounts of sphalerite and some copper minerals. Galena is found to be massive

Jan 1, 1970

By E. H. Bronson

PROPERTY of Malartic Gold Fields Ltd. is situaated in the great clay belt in the northern part of the Province of Quebec. This belt represents the floor of the glacial lake Barlow-Ojibway. The clay blanket has a gently rolling, almost flat surface, with here and there projecting knobs and ridges that outline the large irregularities of the surface on which the clay was deposited. At irregular intervals glacial eskers dominate the landscape. The ore-bearing country rock is covered by strata of clay, sand, and silt to a depth varying to 40 ft. There are serious structural problems when it is necessary to place loads of unequal intensities on this surface to support buildings and machinery for a modern mining plant. Earlier mining companies and their engineers paid little attention to the science of soil mechanics, partly because they believed it unnecessary and partly because they knew little of the subject. The results are evident in some of the tottering structures in older camps. Careful analysis of soil problems is well worth-while, since cost of foundations may vary from 20 to 50 pct of the final cost of a structure. Low operating and maintenance costs can be achieved only in this way.

Jan 11, 1957

By John Fulton

The following table shows the shipments from the four Lake Superior iron-ore districts during the year 1887, and their total outputs from their beginning until the close of 1887.* It will be noted that the Menominee district is second in importance in its total output tonnage to the close of the year 1887. These ore deposits are found in jasper-slates and in the horizon between these and their associated clay-slates; in the latter they are true contact-deposits. They are found in this jasper- and clay-slate formation under varied conditions, yet, in all, certain characteristic laws are preserved. The angle of dip varies from 15° to 20°, and up to 85° and even 90°, with the horizon. The ore is rather soft, bluish-black in color, and is a hematite. It varies in thickness from a few inches to one hundred feet, or more. It is mainly "Bessemer" ore, containing 57 to 63 per cent, of metallic iron, and .03 to .07 per cent, of phosphorus. In the mining nomenclature of this range two conditions of the ore-lens are described by the terms "dip" and "pitch." The former is in common use in defining the relation of the ore-plane to the horizon ; the latter indicates the posture of the ore-body as it inclines east or west from its position at the opening of the mine. In the

Jan 1, 1888

By N. E. Rogen, N. J. Grant

AGE-hardening in nickel-chromium-titanium-aluminum alloys in the composition range characterized by the Nimonic alloys, is dependent upon the precipitation of the Ni3(AI,Ti) (y') phase.1 This phase is found to precipitate at about 700°C.1 Ni,Al is a face-centered-cubic ordered structure with a lattice parameter of 3.560 A. The atomic configuration is such that the aluminum atoms occupy the cube corners and nickel occupies the cube faces with titanium substituting for the aluminum preferentially. A maximum of three out of every five aluminum atoms can be replaced by titanium atoms in the -y 'phase.' When the solubility of the y'-phase is exceeded for titanium the T(Ni,Ti) phase is formed. The T-phase is an ordered close-packed hexagonal intermetallic structure which shows little solubility for the other elements in these alloys. The lattice parameter for T-phase is a - 2.5454 kr and c = 8.2900 kx units."

Jan 1, 1959

Jan 6, 1951

By George M. Schwartz

WHEN reviewing the progress made in mining geology for the year 1953, one might say that not much has been accomplished and, indeed, in a subject such as economic geology not much progress should be expected in the 10 months of the year which elapsed before this article was prepared. This seeming lack of progress, however, disappears when the facts are investigated a bit. There undoubtedly are more economic geologists at work than ever before. It is probably not an exaggeration to say that more geologists are now employed by a single company in the Lake Superior district than were employed in the whole district 20 years ago. In most mining districts geologists are busy with numerous problems of production, development, and exploration and some give an occasional thought to the scientific problems of the science, or rather the art, of mining geology. In fact, this very intense activity of mining geologists is one reason why progress seems slow; they do not have time to write up results of investigations. There is also a great amount of work being done which is not released because of company policy. Conditions have improved very much in recent years but mining corporations, in general, have some distance to go before attaining par with the petroleum industry in this respect.

Jan 2, 1954

By Christa Quiroz

"Uno de los casos particulares en perforación y voladura es la presencia de terreno reactivo, que presenta alta temperatura por sulfuros y puede generar una reacción espontánea con el nitrato de amonio, generando gases por descomposición de pirita y elevación de la temperatura de manera descontrolada. El presente paper trata ésta problemática y aportará a la investigación en el tema, con el objetivo de incrementar la tasa de excavación en el stock de sulfuros transicionales profundos ubicado al sur del tajo Yanacocha, en Minera Yanacocha SRL, Cajamarca – Perú., donde se encontraron frentes duros producto de la compactación del material de relleno. Ante ésta situación, se decidió aplicar perforación y voladura."

Sep 1, 2017

By Dougal R. McCreath, Dwayne D. Tannant, Peter K. Kaiser

The Geomechanics Research Centre at Laurentian University in Sudbury, Canada, has undertaken a five-year research program into the design of support appropriate for control-ling damage caused by rockbursts. Rockburst damage mechanisms in Canadian hardrock mines are reviewed and a support design approach is presented. Each element in a sup-port system performs a reinforcing, holding, or retaining function. The desirable load-displacement characteristics for elements in burst-resistant support systems are described, and recommended support systems are presented for a spectrum of rockburst conditions ranging from minor to severe. A support system can be designed to (a) prevent the triggering of aground fall or a rockburst; (b) deform to accommodate the large imposed deformations arising from a rockburst; or (c) absorb the kinetic energy contained in ejected blocks of rock.

Jan 1, 1996

By Hajime Miki, Mutia Dewi Yuniati, Tsuyoshi Hirajima, Keiko Sasaki

Acid mine drainage is mainly due to pyrite/arsenopyrite oxidation processes, and suppressing such processes is important issue. As a promising process it is reported that silicate ion can complex with catechol (1,2-dihydroxybenzene) and this complex is oxidized to a solid silica layer on the surface of those sulphide minerals. Detailed behavior was investigated from the result of electrochemical experiments. Results of polarization potential showed that oxidation peak can be seen only in the presence of both silicate ion and catechol addition at this peak potential and this peak can be identified as silicate-catechol complex oxidation to silica. Potentiostatic experiments indicated the dissolution kinetics of pyrite. Untreated pyrite dissolution rates were higher than pyrite treated with catechol and silica solution. To enhance the silica layer reaction on pyrite, the pyrite potential was held at 550 mV vs. SHE in catechol silica solution. This pyrite dissolution kinetics was almost the same as untreated pyrite. Potential hold followed by drying for 30 min process resulted in much lower pyrite dissolution rates. Drying is important for development of the silica layer. Analysis of this potentiostatic curve provided a way to estimate the thickness of the produced silica layer and kinetic information of treated/untreated pyrite. Untreated pyrite showed thinner initial layer thickness on the surface of pyrite (oxidized passive layer, not silica) and higher oxidative kinetics of pyrite compared with silica-coated pyrite.

Jan 1, 2014

By Ben Q. Li

An efficient numerical algorithm for solving steady state heat transfer and solidification problems is described. The algorithm is of boundary integral type and is based on the formulation of the field variables along the boundary of the domain of interest. Compared with the familiar domain-based methods, such as the finite element and finite difference (or finite volume) methods, this boundary-based method has an advantage of solving fewer unknowns and hence has a potential for reducing computational time significantly. Another and yet more important advantage of the present algorithm is that it is a stable scheme and is not prone to numerical oscillations resulting from convective effects, as often encountered in the domain-based methods. Therefore, no numerical or artificial diffusion (such as streamline upwinding) is necessary. Numerical examples are presented that are drawn from processing systems for producing aluminum-based materials.

Jan 1, 1994

By Bryce Clark

An outline of the current world's known sources and resources of cobalt, looking at both land and possible undersea deposits, is given as a prelude to an examination of current and historical actual world production on geographic/company basis. These production figures will be compared to apparent consumption by segments, both geopraghically and end-use based. Consumption of cobalt has been regarded as price sensitive and a historical look at prices against all other figures will be considered. Included in this scenario will be a brief overview of cobalt's uses and a comment on future trends. Tables will include: Resources, Production, Consumption, Prices, Markets.

Jan 1, 1993

By Klaus Rabensteiner, Klaus Chmelina

"INTRODUCTION Urban tunneling is often related with special geotechnical risks. Typical causes are difficult (hydro)geological conditions, a very low overburden and the presence of critical and vulnerable (infra)structures in the influence zone of the construction (e.g. existing tunnels, roads and pavements, sewer pipes, gas and power lines, landmarked buildings, historic monuments). To manage these risks appropriately, an early detection and warning of unexpected behavior of the affected geotechnical objects ground and tunnel, as well as existing structures are mandatory. To accomplish this, the design and execution of a dense geotechnical monitoring program is of high importance. In more detail, this means specifying and performing a systematic and continuous acquisition, processing and analysis of monitoring data to support decision making. In recent years the development of new automatic sensors and (wireless) data transfer techniques and the general trend towards an automatic acquisition of monitoring data has led to an enormous increase of data production frequencies and volumes. In order to handle this data explosion efficiently, information systems and geo-databases have been developed and used successfully in many projects. They represent IT tools that support the different tasks of a given geotechnical monitoring program including data acquisition, transfer, check, processing, backup, analysis, distribution, reporting and, last but not least, alarming. Meanwhile, some tools already have developed the capability to connect to other theme-specific databases used in the project and, thus, serve as a central data management system for all kind of digital data produced. This makes possible the implementation of further useful functions and services supporting tunneling tasks such as machine control, tunnel simulation, geological prediction, process optimization, etc. where data from different engineering disciplines must be combined and processed in an integrated way. In the following chapters our aim is to describe how monitoring data management, geotechnical monitoring, alarming and reporting are organized and technically implemented at the metro project Cityringen in Copenhagen (Denmark). We want to highlight the specific role and tasks of the used tunnel information system in the project, and particularly inform on the most relevant challenges."

Jan 1, 2016

By Wayne Bell, Shivanand A. Borkar, Anish Upadhyaya, Matthew D. Andriese, Jiann-Yang Hwang, Zhiwei Peng

"A refractory ore body located in Michigan’s Upper Peninsula contains high concentrations of nickel and copper chiefly occurring in the minerals pyrrhotite, chalcopyrite, and pentlandite. Refractory ore bodies are difficult to treat by conventional mineral processing methods so microwave pre-treatment of the ore is employed to increase metallic-particle/host rock liberation by making use the differential thermal expansion properties of the mineral phases that absorb microwave energy. The Curie temperature measurement of metallic-bearing particles is in agreement with the known value for pyrrhotite occurring at 325°C. A nickel-rich iron sulfide mineral is found to be in occurrence and also appears to be magnetic under BSE imaging. It is shown the ore particles heat rapidly when exposed to microwave radiation for short durations of time mainly due to the high concentration of ferromagnetic mineral phases. Rapid heating causes thermal expansion of constituent mineral phases that produce cracks within ore particles. SEM imaging shows fracture occurring along grain boundaries and throughout host rock matrix. Ball milling experiments show an increased grindability of the ore resulting in a decrease in work index values.IntroductionCrushing and grinding operations consume 50-70% amount of energy used in mineral processing operations [1]. All these processes involve high energy impact of surfaces to develop compressive stresses that produce cracks to initiate breakage of particles. Microwave pre-treatment of certain types of ore might provide an energy savings to these type grinding processes by taking advantage of the tensional forces produced by selectively heating microwave absorbing type mineral phases. The heating of ore particles produces cracking by thermal expansion of the constituent mineral phases. Conventional heating has been investigated and shown to positively aid in grinding processes but determined energy inefficient to be used commercially."

Jan 1, 2011

By Maja Franjic, Ian Tolliday, Chris Collins, James Wiltshire

Ammonium Nitrate Emulsions (ANE) are a large segment of the explosives market for the mining industry. These emulsions are generally designed to be very stable but when breakdown does occur, removal of the resulting thick, crystallized material can be difficult, hazardous, time consuming and costly. A heavily crystallized emulsion cannot be pumped, so manual removal often becomes necessary. Buildup of semi-solid layers of crystallized emulsion can occur in bulk storage tanks or in truck compartments. In these situations, a manual cleanup involving hazardous confined-space entry and a significant amount of downtime is usually required. Once the crystallized emulsion is removed from the equipment, there is very expensive disposal of the resultant waste via a licensed trade-waste company. A much more desirable solution for dealing with waste emulsion is to completely break the emulsion, allowing the oxidizer and fuel phases to separate into two distinct layers. These layers would then be readily pumpable and could be disposed of much more economically. It may even be possible that the separated oxidizer phase could be repurposed as fertilizer and the fuel phase could be used to manufacture granular ANFO explosives. There are some existing products on the market for breaking emulsion explosives, but these generally need a high degree of mixing into the emulsion to achieve adequate breakdown. The aim of this study was to identify surfactants systems (demulsifiers) capable of effectively breaking a range of waste emulsions with minimized agitation. This paper describes the development and performance testing of novel demulsifier products. The test work involved a comprehensive series of laboratory screening tests, where the demulsifier formulations were optimized. A highly efficient formulation was identified, and field trials were conducted on real world, full-scale waste emulsions. Results will be presented that demonstrate a viable solution for the disposal, and potential re-use, of waste ANE in the explosives industry.

Jan 21, 2025

By d&apos, D. L. Guernsey, J. C. Entremont, John Chipman

The reaction of aluminum with oxygen in liquid iron has been studied at 1740° and 1910°C. Interaction coefficients are very much smaller than those previously published. The equilibrium constant falls within the approximate range of earlier experiments and calculations. It is now well established that the "deoxidation constant" for aluminum in liquid steel at normal steelmaking temperatures is extremely srnall. Thus at 1600 the product [% Al] is of the order of 10- 14. At this temperature, therefore, great experimental difficulties are encountered in any attempt to obtain a direct measure of the constant. If the aluminum content of the metal is high enough to permit accurate analytical determination, that of the oxygen is too low. If the oxygen content is high, the aluminum is below the limits of detection. Our best values of the constant have come, therefore, from indirect calculations or by extrapolation downward from observations at higher temperatures.. For their studies in the range 1695° to 1866°C, Gokcen and chipman' restricted their aluminum concentrations to less than 0.06 pct. Oxygen analyses were made by the vacuum fusion method which appears to be dependable at these low aluminum concentrations. Experimental results, even at the highest temperature employed, are extremely sensitive to small errors in the analysis of either element. The slight change in the equilibrium constant with aluminum and oxygen concentration was utilized in the calculation of interaction coefficients expressing the effect of aluminum on the activity coefficient of oxygen and the reciprocal effect of oxygen on the activity coefficient of aluminum. The range of concentration, however, was so limited that only a rough value for the interaction coefficient could be obtained. This value was much more negative than that found for any other pair of reactants. In view of the very limited range of concentration employed, the reported values have always been regarded as very questionable. A redetermination was the object of the work reported here. EXPERIMENTAL METHOD At high aluminum concentrations, the vacuum fusion method is susceptible to grave error due to absorption of gas by aluminum distilled from the sample. Since it was desirable to extend the study to at least as much as 1 pct Al, another method for analysis was sought. In steels containing more than a few hundredths of a percent aluminum and no other deoxidizing element, it is safe to assume that

Jan 1, 1963