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By Goran Mathisson

PLASMARED is a process in which one well established and one new advanced technology have been merged into a practical tool for production of high quality direct reduced iron at lowest energy consumption and costs. Before describing the process, we have to reiterate the simple fundamentals of making metallized iron from iron ores: The main components necessary are: - Iron oxide - Carbon and/or hydrogen - Heat

Jan 1, 1982

By K. V. Raj, VASU GANGRADE

Airflow in large-opening stone mines is largely dependent on the natural ventilation due to the large cross- section area of the opening. The openings of such stone mines are typically twice or thrice the size of typical underground coal or metal/nonmetal mines. Due to the influence of natural ventilation, air velocities as well as the static pressure drop in the mines are low. Mines rely on auxiliary fans to ventilate active faces to reduce contaminant exposure to mine workers. The National Institute for Occupational Safety and Health (NIOSH) is conducting research on ventilation of large-opening stone mines to reduce worker exposure to dust and other contaminants such as diesel particulate matter (DPM). In order to reduce worker exposure to dust and DPM, an understanding of the airflow pattern due to auxiliary fans in the mine is needed. Under this research, NIOSH researchers are exploring the computational fluid dynamics (CFD) modeling to understand the airflow behavior in large-opening mines. In this paper, the team is presenting the results from three-dimensional CFD modeling of airflow in a large-opening stone mine and investigating the effect of a fan placement with the movement of trucks.

Feb 1, 2025

By Philani Larrance Ngwenyama, Ronald CW Webber-Youngman

Through-the-Earth (TTE) communication systems were developed to provide post-accident communication in underground mines. Unlike primary tracking systems, they do not require any major infrastructure installations underground. Instead, they use the Earth’s overburden as the medium or channel for the transmission of electromagnetic waves between surface and underground. Under ideal conditions, TTE communication systems should be able to provide full-duplex, two-way voice, text and data communication. However, this will depend on the design and optimization of the different types of TTE communication systems (that is, antenna and electrodes), and understanding of the rock properties and their influence on the transmission of signals. This can help simulate and model the transmission efficiencies and predict the possible range and data rates. Being able to optimize the performances of these systems can enhance rescue missions, improving the chances of saving trapped miners, and ultimately reduce fatality rates across the mining industry.

Feb 1, 2025

By Roderick K. Davey

The objective is to develop a short-range mining plan which satisfies management and operating criteria and also "dovetails" with the long-range mining plan. In the past years, this objective was accomplished entirely by manual methods. Today, the computer is used to assist the engineer with this task. The results provided by these programs usually are incomplete and require further manual manipulation. The advantage of using the computer programs is that the program can be used to evaluate alternative plans on a first-cut basis minimizing the manual work. Subsequently, the most promising alternatives can be analyzed in more detail, commencing with the first-cut results. In this specific case history, one technique for using computer programs to assist with short-range mine planning will be discussed. Some of the basic operating and management criteria considered directly and indirectly are as follows: (1) operating criteria which include minimum and maximum shovel cut size, equipment performance, haulage roads, requirements for blending, and plant capacities; and (2) management criteria which consist of production requirements, cash flow requirements, return on investment, market demands, and availability of capital.

Jan 1, 1979

By F. G. Schora

The Institute of Gas Technology (IGT), under sponsorship of the U. S. Department of the Interior, Office of Coal Research (OCR), and the American Gas Association (A. G. A. ), has been undertaking the development of one of several processes to convert coal to high-Btu gas as a means of supplementing natural gas supplies. It is anticipated that there will be a significant need for such gas in the foreseeable future in order to meet the ever increasing demands for this preferred fuel form. HISTORY The development of the HYGAS® Process is based on various studies conducted at IGT starting back as far as 1945. Initial work was directed toward production of synthesis gas with subsequent catalytic methanation. By 1964 the concept of the direct hydrogenation of coal to produce methane noncatalytically was well-founded and the chemistry was reasonably well established. Work up until this point in time was financed by the American Gas Association. In 1964 the U. S. Department of the Interior, Office of Coal Research joined with A. G. A. to support the program. The objective at that time was to develop the necessary know-how to enable the design of a pilot plant, a necessary step in the ultimate commercialization of the process. Work for the next three years (1964-1967) emphasized investigation of fluidized-bed technology in the hydrogasification step, where moving-bed technology had been previously employed, as well as identification of commercially available catalysts acceptable for catalytic methanation of the CO and hydrogen in the hydrogasifier effluent under operating conditions in the system. By 1967, the preliminary design of a 3 ton/hr pilot plant had been finalized, and IGT received authorization from OCR to proceed with the detailed design and construction of that facility. The pilot plant was designed to study the following problems:

Jan 1, 1972

By A. Z. Dimitroff

Immediate detection of methane buildup or of sudden liberation of large quantities of methane in the face area is essential to avert disasters in coal mines. Proper timely detection and handling of methane have always presented problems in extremely gassy mines, and these problems have been magnified by present accelerated mining methods. Strict rules and regulations have been established by coal-mining companies, States, and the Federal Government, which provide for periodic inspections for methane in face areas when electrical equipment is working. Other provisions require the operator' to shut down electrical face equipment and change or adjust ventilation when more than 1.0 percent of methane is detected. Nevertheless, human failure to detect such conditions has been responsible for numerous ignitions arid explosions Recognizing this fact, Marling J. Ankeny, former Director of the Bureau of Mines, proposed in 1958 the development of an automatic methane-monitoring device. He envisioned such a device as being entirely dependable, capable of giving a warning when a predetermined concentration of methane in air is reached, and capable of deenergizing the equipment and rendering it inoperative when a dangerous concentration of methane is present in the air. Such a device has been developed by the Bureau of Mines Health and Safety Research and Testing Center in Pittsburgh, Pa.

Jan 1, 1967

By W. A. Hockings

This report describes a computer program for the solution of material balances in complex mineral processing flowsheets. The program, which is entitled MBS Metallurgical Balance System), evolved as the culmination of a series of material balance programs whose development began in 1967 at the Institute of Mineral Research, Michigan Technological University. The need for such a program became evident when the Institute became heavily involved in a large number of short-term pilot plant projects. Calculating material flows from analytical data by means of the standard two-product formulas grew increasingly difficult and time-consuming as the complexity of the flowsheets increased and as choices between conflicting analytical values had to be made. It was recognized that what was needed was a program that would assimilate all of the available data and calculate mass flow rates so that steady-state inputs and outputs would balance at each point in the flowsheet. Such a program should be capable of handling underdetermined, overdetermined and mixed systems, and when the given data are inconsistent, the program should adjust the data in such a manner that the adjustments are minimized. Missing analyses should also be calculated whenever possible. In addition to solving material balances, the program should be convenient to use and print out the results in a useful form. Thus, the inputting of data should be simple enough to be handled by relatively untrained personnel with diagnostic messages being printed out to identify errors and anamolous data when they occur. Most importantly, the program should produce well-formatted output which can be directly included into a report without the necessity of retyping. The proper spacing of table titles, column headings and the ability to control the columns being printed are important features in this respect.

Jan 1, 1977

By Carol A. Hill

Native sulfur occurs with barite, celestite, and bioepigenetic calcite in the Culberson, Pokorny , and Leonard Minerals deposits, Delaware basin. The sulfur in these deposits, in "castile" masses, and in deposits of the Fort S tockton district have 6 34s values between +9 and -15. Native sulfur in the caves of the Guadalupe Mountains is somewhat lighter [(634s = -15 to -25)]. Barite in the Culberson, Leonard Minerals, and Comanche Creek sulfur deposits have 63% values of +35 to +73; celestite in the Culberson and Leonard Minerals occurrences have values of +38 and +36, respectively, and 87Sr/86Sr values of 0.707808 and 0.708138, respectively. Barite associated with sulfide, deposits, Guadalupe Mountains, have [634s] values of +41 to +62. Barite at Seven aeart Gap, Apache Mountains, is somewhat less enriched in heavy sulfur [(634s = +14 to +37)].

Jan 1, 1992

By Anthony W. Garson

Good morning, ladies and gentlemen: It is a pleasure to be here this morning as a representative of Dean Witter Reynolds; one of the foremost international investment firms in North America. My colleague, Hugh Wilmer (who will be speaking to you a little later), and I are involved as research analysts in the research and writing of published reports containing recommendations on the buying or selling of North American and South African gold and silver mining shares. Our talk this morning will focus on the gold mining operating costs of North American and South African gold producers. However, I am not going to bore you with reams of statistics on the operating costs of large numbers of gold mining operations; how meaningful would this data be to you? Instead, I will discuss what the investor should look for, and how he should use this knowledge in making his investment decision.

Jan 1, 1984

By K. V. Raj, C. A. Berry, A. T. Weakley, A. L. Miller, P. R. Griffiths, D. A. Parks

Diesel particulate matter (DPM) has been classified as a carcinogen to humans by the International Agency for Research on Cancer. As a result of its potential carcinogenic nature, DPM exposure is regulated by the Mine Safety and Health Administration. Currently, diesel emissions in the workplace are monitored by collecting the aerosol onto filters, which are then sent to a laboratory for thermal-optical analysis using the NIOSH method 5040. This process can take days or even weeks, and workers can potentially be exposed to excessive levels of DPM before the problem is identified. Moreover, the delay involved in getting the loaded filter to the lab inevitably means the loss of some of the more volatile organic carbon. To remedy this delay, researchers from the National Institute for Occupational Safety and Health are seeking to develop a field-portable, real-time method for measuring elemental and organic carbons in DPM aerosols. In the current study, the use of mid-infrared spectrometry was investigated. It is believed that mid-infrared spectroscopy is more suitable for use in a real-time field-portable device than thermo-optical analysis methods. This article presents a method for measuring organic carbon (OC) and elemental carbon (EC) in DPM for a broad range of OC/EC ratios. The method has been successfully applied to laboratory-generated and mine samples.

By Taghi Sherizadeh, KUTAY E. KARADENIZ, Dogukan Guner, Samuel Nowak

Underground mining environments bring with them occupational health and safety issues with some severe dangers, such as mine explosions. During such events, miners may escape using main access openings or find a safe haven like a refuge alternative (RA) to wait and be rescued and evacuated to the surface. In this paper, RAs are explained with their early and current applications. A classification as permanent and portable is detailed, depending on conditions and abilities. This classification is followed by the utilization and survivability of RAs with the requirements and recommendations of the main mining countries. Based on the utilization and survivability constraints, basic human requirements, waiting for a rescue team, and the required physical specifications of RAs during the events are analyzed in detail for various countries with their regulations. Among these, the specification of resistance to explosion is discussed in particular, and studies in the literature are examined in terms of structural deformation.

Mar 1, 2023

By I. Iwasaki

There are many reasons why the US mineral and primary metals industry is in its present state. Undoubtedly, a flood of imported goods in all sectors is playing a major role in the plight of our raw materials industry. Domestic industry is becoming increasingly aware of the importance of its international competitiveness. And we are beginning to wonder what is happening to our technological edge. A number of factors affect the international competitiveness. Engineers cannot do much about some of these factors - labor costs, tax policy, government relations, interest rates, dollar strength, and labor-management relations. Something can be done about technology, however. Some say technology is so easily transferable today. But I would like to believe that we have the ability to apply it better than others. Not too many years ago, "made in Japan" meant cheap and shoddy products. Today, Japan has completely changed its image. The US is beginning to feel the threat from Japan's low-cost, defect-free products with dependable delivery. With worldwide recession and the strength of the dollar, we were shocked at the sudden weakness that developed in America's industries, not only in the international market, but domestically as well. What went wrong and what can we do about it? Senior executives from 300 large American manufacturing companies were surveyed. These executives believe US companies must: • invest in more efficient plants and equipment (27%); • invest in more research and development (23%); • improve the quality of service to customers (23%); and • adopt more aggressive marketing tactics and strategies (14%). Are we not doing enough research? The US has nearly four times as many people engaged in research and spends four times as much for research as Japan (Fig. 1). There is little doubt about the excellence of the US performance in basic science as indicated by the number of Nobel prize recipients. Japan has produced only four winners since World War II. Look at technology trade of five countries (Fig. 2). Again, US performance has been remarkable. An interesting observation here, is that the United Kingdom, another country with economic woes, is also in the black, West Germany and Japan, both with trade surpluses, are net technology importers. It is apparent that the US' performance in the commercialization of new knowledge is much more in question. Japan had $50 billion of trade surpluses with the US last year, which led to some friction between Washington, DC and Tokyo. Comparing the technology trade of Japan and the US in more detail, Japan imports disproportionately large amounts of technology from the US and Europe. This data is rather old, 1978, but the general trend is not too different even today. It is generally believed that scientific research leads to innovative technology, then to economic payoff. But, after seeing the current technological challenge by Japan, we are forced to change this traditional view. Investment in research may eventually lead to economic payoff, but not directly. There is a middle ground between new knowledge and its commercialization. This is an area where the Japanese have been successful. Until the 1970s, many western companies licensed patents to Japan for quick profits. But, in recent years, these companies have become more discrete about the terms of technological transfer. As a result, a number of scientists and engineers are expressing deep concern over the future of technological developments in Japan. A survey was conducted on 450 research managers of private industries in Japan on how they viewed the level of breakthroughtype original research in Japan as

Jan 6, 1986

By A. C. Lordi

Present industrial plant design is influenced by motivators beyond the usual powerful one, creativity, on which Consultants thrive. The respected, although annoying, ever-present Return on Invested Capital becomes even more significant with anticipated escalation. Government regulations are having an increasing influence as air and water protection, sound and electrical safety requirements must be met And more recently, the increasing cost and uncertain availability of energy sources are having a revolutionary affect on plant design. More than ever before, the Consulting Engineer is faced with requirements and restrictions which tax even the most original thinkers -- and the result is good. This paper includes a brief review of recent trends in Cement Plant Engineering Design.

Jan 1, 1975

By John M. Smith

Kaolin is an important industrial mineral because of its unique properties and low cost. Strictly defined, kaolin is the name given to a group of hydrous aluminum silicates of which kaolinite is the most common mineral (1). Through common usage the mineral, kaolinite, is called "kaolin" or "china clay". In 1972 over 4, 000, 000 tons of kaolin will be beneficiated and shipped by domestic producers. By far the largest user of kaolin is the paper industry which utilizes approximately 65 to 70 per cent of the total production. Kaolin is used in paper as a filler in the interstices of the sheet and as a coating to impart smoothness, gloss, brightness, and printability to the paper. The rubber industry is also a large user of kaolin where it is used as a filler because it adds strength, abrasion resistance, and rigidity to both natural and synthetic rubber goods. Kaolin is used as an extender in paints because it is chemically inert, has a high covering power, gives desirable flow properties, and is low in cost. In ceramics, kaolin is used in whitewares, tile, insulators, refractories, and in some face brick where a white color is desired. Kaolin is also used extensively in plastics as a filler in thermosetting and thermoplastic mixes to give smoother surfaces, a more attractive finish, good dimensional stability, and resistance to chemical attack. Many other process industries use kaolin as a filler, suspending medium, or for color improvement.

Jan 1, 1972

By D. Lelinski

Air-sparged hydrocyclone (ASH) flotation is one of the new promising technologies. Numerous applications have been successfully tested since its conception; nevertheless, research and development efforts have continued to provide for further improvements with respect to operating conditions and design considerations. Results from experimental studies on bubbles generation in the ASH system are presented in this paper. Bubble size distributions generated during ASH operation have been determined using a high-speed photographic technique. The influence of many factors including surfactant concentration, water flowrate, and porous tube pore size has been studied. Test results indicate that these process variables have a profound effect on the bubble size distribution. With an increase in surfactant concentration or water flowrate (shear field) the bubble size distributions become narrower and shift toward smaller average bubble diameters. However, the influence of pore size is more complicated. Depending on the experimental conditions the average bubble size was found to range from about 100 to 300 microns in diameter.

Jan 1, 1995

By Nikhil Dhawan, Veeranjaneyulu Rayapudi, Singh Rahulkumar Sunil

The ever-increasing demand for steel and the subsequent depletion of high-grade ores requires the massive utilization of low-grade iron ores. In the present study, an iron ore slime sample containing 56.1% Fe was investigated using physical beneficiation, carbothermal reduction, and a microwave-assisted process; however, physical beneficiation and microwave exposure were found to be inefficient as they yielded lower iron recovery. Using coconut shell as an alternative reductant was found to be promising and does not lead to the formation of higher iron oxides, such as fayalite and wustite phases. The microwave-assisted carbothermal reduction was found at par with conventional reduction, saving time and heating. The optimum magnetic concentrate obtained in both carbothermal reduction routes (microwave and muffle furnace: Fe grade, Fe recovery, and yield of 64.3, 97, and 84%, and 67, 99, and 83%, respectively) are suitable for alternative iron-making or blast furnace units.

Miners really are an optimistic bunch. Even with the dark clouds hanging over the global industry, mining professionals still turn out in droves at industry conferences. In February, more than 7,200 professionals attended SME?s Annual Meeting in Denver, CO, a record. And the following week, more than 30,000 people converged on Toronto, ON, Canada for the Prospectors and Developers Association of Canada (PDAC) meeting. For many small and junior mining and exploration companies the PDAC conference is a place to find potential investors in their projects. The Investors Exchange attracts several hundred companies, each showing off their properties to the many money types who wander the hall during the four-day conference.

Jan 1, 2013

By M. A. Reyes, L. Yan

Heat and humidity buildup withn refuge alternatives (RAs) may expose occupants to physiological hazards such as heat stress. The Mine Safety and Health Administration (MSHA) regulations require RAs in underground coal mines to provide a lifesustaining environment for miners trapped underground when escape is impossible. RAs are required to sustain life for 96 h while maintaining an apparent temperature (AT) below 95 °F (35 °C). The National Institute for Occupational Safety and Health (NIOSH) tested a 10-person tent-type RA, a 23-person tent-type RA, and a 6-person metal-type RA in its underground coal mine facilities to investigate the thermal environment over a 96-h period. The test results showed that mine air and mine strata temperatures surrounding an RA occupied by simulated miners (SMs) increased over the 96-h test period. The test results suggest that RA manufacturers should consider this increase in temperatures when calculating and evaluating RA components during surface and laboratory tests. The findings can equip stakeholders with additional considerations for calculating the interior heat and humidity temperature profiles for occupied RAs not tested in situ.

By T. Faulkner, S. A. Richards

"Classic engineering economics provides the mining engineer with a fundamental approach to choosing between capital spending alternatives. This approach has been heavily used over the years and is an accepted technique for most investment decisions. There is a shortcoming that I have run into over the 15 year period when I worked in business planning roles. The classic time value of money approaches such as Net Present Value, Return on Investment, and Internal Rate of Return provide good estimates, but the input assumptions may fall short of describing the real material differences required by these analysis techniques. If the cost benefit analysis is defined solely on the improvement of the item being replaced or improved, the true profitability of the decision may be overestimated. Productivity improvement based capital projects can yield more accurate forecasts when conducted in concert with a “bottleneck analysis”. INTRODUCTION A review of the Theory of Constraints, (Goldratt, Cox, 1984) Lean, (Womack, 2003) (Rattner, 2006) and Six Sigma (Cryger, DeFeo 2015) lead us to recognize that these process improvement methodologies are oriented to the manufacturing process. These systems generally involve a factory that the material moves through on the way to becoming a final product. The mining challenge has many similarities to manufacturing once the ore has been won and made ready for processing. Before that point, however, the process is somewhat inverted while the ore is being won. Instead of the material moving through the factory, the factory is moving through the material. The Theory of Constraints (TOC) was used in an underground context by Baafi, Cai and Porter at 2015 APCOM, but even this groups’ analysis did not carry the concept from mining to shipping of the final product. There can be spatially distributed data that can affect the mining throughput constraints, some of which can be determined from exploration results. Identifying constraints can lead us to mapping productivity bottlenecks on future mining. Knowing this may improve decision making by eliminating one of Jim Fishbein’s three deadly sins of strategic planning: incomplete planning. When evaluating capital investment alternatives you should evaluate the impact of any proposed improvements on the entire operation. At the core of any mining system is the materials handling system. This can be typically expressed as the system that handles the raw material from the “face” through processing and then handling the finished product as well as the waste material. A “Bottleneck Analysis” is an investigation into the factors limiting a material handling system’s productivity (Goldratt, Cox, 1984). Mining material handling systems are usually composed of several linked components such as draglines, shovels, loaders, hydraulic excavators, continuous miners, longwalls, highwall miners, bucket wheel excavators, LHDs, feeders, conveyor belts, stockpiles, crushers, processing plants with various circuits, and waste handling systems. Each of the aforementioned components has a slightly different throughput capacity. When these are linked in series, the one with the lowest throughput capacity limits all of the others, creating the bottleneck for the system. Every material handling system has a bottleneck. In the mining environment, a subtle, but very significant phenomenon may also occur. The bottleneck may change as a result of a change in the raw feed qualities, face recession, overburden depth, digability, learning curve, and many others factors which may be derived from the drillhole data. These parameters often change as a function of the location in the reserve base, and may also vary with time."

Jan 1, 2016

By George Bárdossy

Most of the bauxite deposits in Europe belong to the karst type. They are located mainly ill Southern Europe along the Mediterranean Sea and in the Ural Mountains. Lateritic bauxite deposits occur on the Russian Platform, in Poland, Northern Ireland and in Turkey. Tikhvin-type deposits arc found on the Russian Platform. Bauxite formation in Europe started in the Middle Devonian. The main bauxite forming period was the Upper Cretaceous. Very few bauxites are younger than Eocene. Most deposits are covered by overburden of up to 1000 m. Prospecting is carried out by drilling. Several geophysical methods are used to detect the hidden deposits. Geostatistical methods were introduced in several countries for evaluation of the reserves and the geometry of the deposits. Data on bauxite production are given for 1982 and since the beginning of mining in Europe.

Jan 1, 1984