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By S. J. Oosthuizen

This paper examines innovation in relation to the availability of anew material: the metal titanium. The paper aims to highlight the need for the inclusion of entrepreneurial innovation as a necessary focus area in the development of a titanium metal value chain. Both the Department of Science and Technology (DST) and the Department of Mineral Resources (DMR) have identified the creation of titanium metals production capabilities as a key growth area for South Africa. Using historical literature as a source of data, the activities of selected innovators who used titanium metal as a central component in their success, were investigated. The origin of the process innovation behind the titanium metals industry, and two titanium product innovations: namely, medical implants and sporting goods, were detailed as case studies. It was found that individual innovators were responsible for the creation, and rapid growth, of the titanium industry and titanium product applications. There is a need to link the current research and development into titanium metals production with individuals and organizations capable of commercializing innovative processes and products.

Jan 1, 2011

By John Gross

Studies in grinding efficiencies carried out at the Midvale plant of the U. S. Smelting, Refining & Mining Co. and at the Tooele plant of the International Smelting Co. Were made possible by the cooperation of these two companies with the U. S. Bureau of Mines. Mr. Alan Probert of the U. S. Smelting, Refining & Mining Co. and Mr. E. C. Peterson of the International Smelting Co., devoted their entire time to the work during the respective tests, and their services are hereby gratefully acknowledged. It is a pleasure to acknowledge also the assistance and kindness of the staffs of both companies in making it possible, at considerable trouble and expense, to sample the entire mill circuits and in furnishing the necessary supplies and special apparatus required in the work.

Jan 1, 1929

By J. G. Eacott

This paper reviews the role of oxygen potential and the advances that have been made in the application of tonnage oxygen in copper smelting. Brief reference is made to reaction kinetics before attention is turned to the thermodynamic considerations in copper melting to illustrate the importance of oxygen and. oxygen potential in the component parts of the overall smelting process. The chemical potential diagram for the Cu-Fe-S-O-Si02 system is used to elucidate the difference b etween the conventional matte smelting process and the modern continuous processes. A progressive oxidation scale' is constructed to show the common elements which exist, and the matte grades produced, during the smelting of concentrates to blister copper in commercially available copper smelting processes and those under development. The common route in producing blister copper from molten mattes, regardless of process, is illustrated on the Cu-Fe-S equilibrium phase diagram. The essential features of oxygen enrichment, in terms of its effect on combustion conditions (i.e. oxidation of fuel and sulphide minerals) and the heat balance are outlined. The benefits of oxygen enrichment are listed. The influence of tonnage oxygen and its effect on productivity, fuel savings, gas volume and strength in various copper melting processes are examined as a state-of-the-art review. Reference is made to the economics of tonnage oxygen utilization.

Jan 1, 1983

By N. D. Schupp

The Doe Run Company's Herculaneum, Missouri lead smelter has existed in continuous operation since 1892. Throughout the history of the plant extensive developments have been made to improve throughput, increase productivity, decrease operational costs and improve technology, while remaining an environmentally responsible producer of high quality primary lead in the international market. This paper provides an overview of the Herculaneum smelter, focusing on the most recent configuration of the operations. The paper includes discussion on all the aspects of primary lead production at the Herculaneum smelter.

Jan 1, 2000

By P. Dennis, T. Pieters, A. De Kievit, S. Ganguly

TEMCO has been producing manganese ferroalloys in submerged arc electric furnaces for over 40 years. The furnace linings all along have been of conventional insulation type until 2001 when a freeze lining of UCAR concept was installed for a 20 MW Furnace. Continuous improvement of furnace lining performance has been a key component in improving the business competitiveness of TEMCO. The expected minimum campaign life of the freeze lining is fifteen years as compared to the ten years of the conventional linings. The success of the freeze lining is very critical to the quanta and direction of heat flow through the lining that control the freeze protection. Under freeze protection can lead to reduced lining life and over freeze protection, on the other hand, can lead to operating difficulties and loss of smelting efficiency. It was, therefore, necessary to develop a computer based system to monitor and control the freeze protection. The computer based monitoring and control system uses the basic principles of heat transfer, activeX object and heat flux from dual thermocouples and that is reviewed.

Jan 1, 2004

By N. A. Gokcen

In this Bureau of Mines report, appropriate equations correlating the activity of water with the activities of electrolytes in binary and multicomponent solutions have been derived for computer calculation. It was found that the half-integer power series are far superior to the integer power series, for both types of series having the same number of terms. The pro-posed method of calculation is capable of accurately yielding the activities of all components from the measurements of the activity of a single component at various concentrations. This method replaces the cumbersome and objection-able method of graphical integration of the Gibbs-Duhem equation. Two novel methods are proposed for determination of activities of electrolyte solutions important in hydrometallurgy; (1) Water vapor pressure measurement by differential pressure transducers having an accuracy of 0.001 pet, and (2) transpiration method with an inert gas bubbled through concentrated solutions followed by the analysis of the evaporated and redissolved electrolytes with specific ion electrodes having a sensitivity of ±10-10 molal. The first method is suitable for nonvolatile electrolytes, and the second, for volatile electrolytes such as hydrogen halides, HN03, H2S03, etc. The existing methods of estimation of ionic activities have been surveyed, and the best method has been selected, discussed, and summarized.

Jan 1, 1979

By C. A. Herbert

In summer, when hot, moisture-laden air enters a coal mine in the region east of the Mississippi River, the moisture is likely to condense on the roof and ribs because the incoming air is cooled below its dew point upon contact with the roof, ribs, and floor of the mine passageways. When the roof and ribs become wet owing to this condensation they are said to "sweat." In many mines, as soon as this sweating begins, shale or slate roof that appears solid and strong in winter begins to cut and fall. For a long time most mining men believed (many still believe) that the roof trouble was due to this sweating. However, from observation of conditions in one mine the operators concluded that the trouble was caused by expansion and contraction of the roof due to changes of temperature. This opinion was confirmed by experiments at several mines in cooling the air as it entered the mines. Methods used in these mines for cooling the air are described in this circular. MINE A At mine A the roof gave considerable trouble in the summer, and it was observed that where a spray of water from a leaking dam kept the roof wet and at a uniform temperature no difficulty was experienced with the roof, although it had cut and fallen on either side of that point. From this fact the company officials concluded that changes of temperature in the air rather than moisture caused the trouble and that if the incoming air were cooled to approximately normal strata temperature much of the additional roof trouble experienced during the summer would be overcome.

Jan 1, 1940

By D Audeyev

The Cooljarloo North Mine has been shaped not only by operational and processing challenges, but by climatic and economic factors. This paper outlines some of these challenges and discusses how the operating strategy has been altered over time to mitigate the impacts.Since commissioning the wet concentrator in 1999, there have been many typical operational challenges to maximising valuable heavy mineral (VHM) recovery. These include: varying in pit feed grades, different slimes types and volumes, sizing extremes between VHM and trash minerals and decreased equipment reliability handling rocky ore. These issues were successfully mitigated by: in pit extraction strategies, upgrade of the de-sliming circuit, thickener modifications and flocculent changes, installing upgraded and additional spiral capacity, and various Feed Preparation Plant screening initiatives. Combined with the ingenuity, persistence and patience of the operating team, VHM recovery >95 per cent has been achieved.However, typical processing challenges have not been the only hurdles. Reduced rainfall and water availability has necessitated the strategic co-disposal of tailings and slime to increase the speed of water recovery: groundwater abstraction and water storage strategies have also been altered. With an observed reduction in the speed and magnitude of groundwater recharge, overburden backfill scheduling has become a priority mine planning function.Combined with the above challenges, the prevailing foreign exchange rate and mineral product prices have impacted profitability. At the height of the Global Financial Crisis in 2009, major changes to the operating strategy were made to maintain a viable dry mining operation in 2010. Working with the mining contractor the existing scraper and semi-fixed Feed Preparation Plant set up was replaced with a movable in pit dozer trap facility. The end result of changes to the mining method and primary screening was a ten per cent reduction in unit costs. This article will elaborate on some of the above mentioned challenges and successes achieved over the past ten years of operating the Cooljarloo North Mine.

Oct 5, 2011

Improved roof control in high deformation tailgate environments has been achieved over the last decade through development of stiffer and increased capacity standing support products. æThe CanÆ is one such development, being a steel cylinder containing a weak cementitious fill, designed to essentially fold in upon itself whilst maintaining strength. A laboratory study to better define the relative load contributions of the steel cylinder and fill, the confining interaction between these components and most importantly, the potential impact of varying the steel and/or fill properties is described. This would enable the support engineer to ædial-upÆ the desired strength and stiffness properties and optimise the standing support design with respect to load capacity, stiffness, weight (handling) and cost. Design curves to optimise strength based on steel casing thickness, fill strength (confined and unconfined) and æCanÆ geometry were established. Scaled-down (one-third) samples were used in the test program and found to adequately reflect the loading behaviour of full-scale versions, thereby providing significantly greater scope for further product development at less expense compared with testing full-scale products.

Jan 1, 2005

By David F. Gearhart

A cooperative study was conducted between Signal Peak Energy and the National Institute for Occupational Safety and Health (NIOSH) to evaluate the behavior of a pre-driven recovery room under less than 200 ft of cover. The design of the support systems for a pre-driven recovery room must provide control of the roof and ribs during the changing stress environment experienced throughout the final advance of the longwall into the recovery room. It must also provide a stable area where mine personnel are not exposed to undue hazards during shield recovery operations. This recovery room was constructed in two phases; each phase mined a 21-ft-wide room that was heavily supported, and subsequently fully backfilled with 800-psi, cellular concrete. Instrumentation to monitor the recovery room performance included borehole pressure cells (BPCs) placed in the head gate and tailgate pillars, at four locations across the longwall panel, in the fill material, and in the first row of outby pillars near the center of the panel. Four roof-to-floor convergence sensors were installed in the back fill material and a vertical, multipoint borehole extensometer (MPBX) measured the displacement of the strata above the recovery room. Surface surveys were conducted to measure MPBX collar movement. The data show that the front abutment load was transferred onto the recovery room backfill and the out by pillars as the longwall panel was extracted. As the longwall approached the recovery area, the fender and shields yielded, but the backfill provided enough support to keep the room stable as the longwall advanced to its final position. The system worked as planned and the face was recovered in record time.

Jan 1, 2014

By V. A. Nieberlein

Problems of design involving the high-temperature characteristics of materials of construction have focused attention on tungsten, the metal with the highest melting point. To study the properties of this metal a method was needed to produce tungsten of high purity easily and consistently. The Bureau of Mines has made tungsten metal in massive form on a laboratory scale by hydrogen reduction of tungsten hexafluoride (WF6). Metal made in this manner had a purity of 99.99 percent or better, with reference to all detectable impurities, including gases. The process tolerated a wide variation in operating conditions, and the results with respect to total impurities as low as 0.01 percent were reproducible.

Jan 1, 1959

By P. L. Drake

This paper comprises a discussion of the role which mineral resources will play in Canada's future export trade and the growing demand for minerals in Canada.

Jan 1, 1979

This paper examines the feasibility of combining network modeling and computational fluid dynamics for modeling of underground mine ventilation systems. Both simulation methods have specific advantages and disadvantages for analysis of mine systems. Network modeling is widely utilized by many operations and allows for assessment of current systems and simulation for planning purposes. Alternatively, CFD has been utilized only marginally by operations and is typically a research tool, requiring considerable computational power, complex models, and careful analysis and calibration of results. Network modeling allows for a holistic approach to the ventilation system, giving quantity, velocity and pressure in every branch, but CFD modeling can resolve the flow regime in 2-D or 3-D, which is idea when examination of an area on a more detailed basis is useful, such as dust and gas control. Integration of the two can allow for more flexible systems analysis. The feasibility of integration, along with application to limited underground mine data are examined.

Feb 23, 2014

By Mingming Zhang, Mallikharjuna R. Bogala, Ramana G. Reddy

Steelmaking desulfurization slag samples were characterized using chemical, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) methods. The objective of this work is to investigate the occurrence of sulfur and phosphorus components in the slag samples and to identify their origin and associations with the iron phases. Thermodynamic calculations results confirm the presence of phosphorus and sulfur components in the slag sample at high temperatures (1400 to 1800oC). The main constituents of slag include Ca3SiO5 (28.1%), MgO (9.31%), Ca3(PO4)2 (9.18%), CaS (8.39%) and CaO (5.68%). The major phosphorus and sulfur components of the slag are Ca3PO4 (99.2%) and CaS (79.3%) respectively. Characterization studies indicate the presence of microparticles of different sizes and shapes in the slag sample. Elemental analysis of these particles confirm the presence of major elements (O, Mg, Al, Si, S, Ca and Fe) in the slag sample.

Jan 1, 2015

By Dermot M. Ross-Brown

The more important factors controlling the design of pit slopes are related to the local geology over which the designer has little or no control. Nevertheless, there are some factors over which the designer does exert some control and these concern the say in which the rock is excavated and supported. They include blasting, face cleaning, water control, and the use of rock improvement techniques. The paper discusses these factors and relates the extra costs incurred to the steeper slope angles that can usually be obtained. It is demonstrated that even a modest increase in bench angle of 5° through improved excavation techniques can pay off in a single push-back.

Jan 1, 1975

By C. Cho

One problem with the application of neural networks to the multivariable control of mineral and extractive processing is deciding whether and how best to use them. The objective was to compare neural network control to more conventional strategies and find any advantages in terms of set point tracking, rise time, settling time, disturbance rejection, and other criteria. The procedure was to develop neural network controllers using both historic plant data and simulation models. We tried various neural network control patterns including both inverse and direct neural network plant models. These were compared to state space controllers that were, by nature, linear. For grinding and leaching circuits, a nonlinear neural network-based model predictive control strategy was superior to a state space-based linear quadratic Gaussian controller. We also learned the importance of incorporating state space into neural networks by making them recurrent--feeding certain output state variables into input nodes in the neural network. We concluded that neural network controllers can have better disturbance rejection, set point tracking, rise time, settling time, lower set point overshoot, and can be more foolproof and easy to implement in complex, multivariable plants.

Jan 1, 1996

By C. M. Harrer

This paper describes the location, features, qualities, extent, and potential of iron occurrences and some associative resources -limestone and dolomite, coal, petroleum and natural gas, power, and water - in New Mexico. Reconnaissance investigations were made of 118 iron occurrences to deter-mine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential iron markets are discussed. The most abundant iron minerals are magnetite and hematite. The higher grade deposits are extensive contact-metamorphic and pyrometasomatic replacements in calcareous Paleozoic rocks associated with intrusives. Low-grade deposits of considerable potential are the extensive Cambrian oolitic hematites of sedimentary origin and the Precambrian magnetite-hematite taconite iron formation. Iron occurs also as extensive colluvial and alluvial concentrations. A wide variety of accessory elements are indicated and these pose metallurgical and economic problems.

Jan 1, 1963

By C. M. Harrer

This paper describes the location, features, qualities, extent, and potential of iron occurrences and some associative resources - limestone and dolomite, coal, petroleum and natural gas, power, and water - in New Mexico. Reconnaissance investigations were made of 118 iron occurrences to determine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential iron markets are discussed. The most abundant iron minerals are magnetite and hematite, The higher grade deposits are extensive contact-metamorphic and pyrometasomatic replacements in calcareous Paleozoic rocks associated with intrusives. Low-grade deposits of considerable potential are the extensive Cambrian oolitic hematites of sedimentary origin and the Precambrian magnetite-hematite taconite iron formation. Iron occurs also as extensive colluvial and alluvial concentrations. A wide variety of accessory elements are indicated and these pose metallurgical and economic problems.

Jan 1, 1963

By O. W. Kamper

To most of you present here the word "refractories" is not new and you are familiar with the materials and use. To many people though the question is asked, "What are refractoriness and what are they used for?" Refractories are non-metallic products which are so resistant too melting at very high temperatures that they can be used for building or lining furnaces of all kinds. A large variation occurs in the size, form, and composition depending on the service for which they are intended. They are made from a wide variety of raw materials, of which fire clay and quartzite are used in largest quantities. Other refractory raw materials include magnesite, chrome, diaspore, bauxite, kyanite, sillimanite, olivine, zircon, and many others. Most of these are assembled from-widely-'separated points in the United States while others come from the far corners of the earth. Chrome is imported from the Philippines and South Africa, and, to a lesser extent, Turkey and Greece Kyanite and sillimanite come: from India and bauxite from the Guianas. And there's "magnesite from brines," produced in chemical plant's by treatment of sea water or inland deep-well brines with hydrated lime. The proportion of magnesia available in sea water is so small, less than one pound from 500 pounds of water,, that millions of gallons must be pumped and processed each day in a sea water magnesite plant. The realm of refractory raw materials, therefore, is very extensive and continues to grow because of the endeavor to find-better raw materials from which to produce better products for refractory service.

Jan 1, 1960

Mining is big business in Ontario. The province is Canada?s leading mining region. It consistently ranks among the top 10 jurisdictions worldwide for exploration spending, reaching about C$1 billion in 2011. More than 26 percent of all exploration and appraisal dollars spent in Canada are invested in Ontario. Minerals produced include nickel, copper, platinum group elements (PGE), cobalt, zinc, diamonds, gold and silver. It was reported that there are more than 600 mining exploration projects in the province. And, recent discoveries of chromite in northern Ontario?s Ring of Fire will add to the province?s mineral production in the coming years.

Jan 1, 2013