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By A. Vervoort, A. Govaerts

Geostatistical concepts are often difficult for students to understand, even those with a strong mathematical background. One of the main problems is the link between the variation of the parameter value in space or time and the calculated experimental semivariogram. Another challenge is differentiating between directional and omnidirectional semivariograms and their interpretation. For these reasons, interactive tools were developed based on the free public domain software R. The use of these interactive tools is limited to educational situations only (i.e., to visualize basic concepts). The interactive modules can be accessed at www.bwk.kuleuven.be/geostatistics.

Jan 1, 2014

By Biswajit Samanta, Pranjal Pathak

This article presents a customized genetic algorithms (GA) with new crossover and mutation operators to solve the short-term production scheduling problem of multi-mine mineral value chains (MVC). The preceding problem consists of determining the extraction sequence and destination allocation of blocks from all the mines collaboratively while closely meeting the quality and quantity requirements of the processing units subject to relevant technical and operational constraints. The short-term production scheduling is carried out at shorter scales wherein the operations are modeled in a great detail with large number of constraints. This makes the industry-scale instances of the problem computationally intractable for standard mixed-integer programming (MIP) solvers. Thus, a GA-based heuristic approach is developed to obtain nearoptimal solutions to the large-scale instances of the problem in a reasonable amount of computational time. Computational experiments show that the developed GA-based method is a promising way to handle industry-scale instances of the problem. Moreover, the sensitivity analysis on various parameter combinations of crossover and mutation operators indicates that the customized global mutation operator, when used in combination with the customized crossover operators, took on average 12.5% less time than the customized local mutation operator to converge to a solution.

May 21, 2022

By J. R. Thoenen, B. H. Clemmons, A. H. Reed

"INTRODUCTION AND SUMMARYOverall red-ore reserves in the Birmingham, Ala., area were estimated in 1910 by E. F. Burchard 4/. Since then mining has progressed into areas classed by Burchard as ""unavailable for exploitation"" under conditions existing at that time. This is understandable when it is considered that red iron ore was valued at $1.19 a gross ton at the mine in Birmingham in 19102/ and by 1948 had risen 300 percent; 6/ that skips had replaced cars in slope haulage; that mechanical loading and rubber-tired haulage had replaced hand loading and mule or locomotive haulage; and that other more efficient mining methods had been introduced. Intensive study during the intervening 40 years has been given to ways and means for upgrading the low-grade ores in the area and combining or blending them with raw red and brown ores for improved blast-furnace feed.It is reasonable to expect that future progress in mining efficiency and increased knowledge of the beneficiation characteristics of marginal ores will permit extraction of red-iron minerals now considered uneconomic.The Bureau of Mines has undertaken to restudy iron-ore reserves of the Birmingham area to determine what tonnage and grades of mineral are present; what is necessary to make them amenable to mining; what further advancement is possible in beneficia¬tion methods; and where increased production may be obtained in the area if and when required. This study has been underway for the past 2 years, but research into the beneficiation of marginal ores has been in progress at the Southern Experiment Station for the past 30 years. Many results of that research have been adopted in commercial practice in the area. Other results have not been published but are pre¬sented here in condensed form as an important factor in assessing marginal deposits with respect to their importance as ore reserves.An interim discussion of the salient features of past history and progress, as well as the data developed during the years of research in beneficiation at this station and the present field investigation, will make for a better understanding of the present position as well as be useful in evaluating future potentialities. Discussion in this paper is confined to the main Birmingham Basin area, which contains the largest concentration of hematite ores in the district."

Jul 1, 1953

By Andrukaitis. E.

The increasing use of electronic equipment by the Canadian Forces has increased the importance of electric power. A power source that is packed with energy and yet light, small and durable is the common request of military users. However, this needs to be achieved while also addressing the requirements of safety, reliability and low temperature performance. The potential use of fuel cells in a military environment has become a possibility in several areas in the 21st century. Some examples of power source requirements and the materials related R&D required to give better, higher energy power systems in the future will be discussed.

Jan 1, 2005

By R. D. Currie

"INTRODUCTION Compressed air for operating coal-mining equipment is seldom considered in conjunction with modern methods and appliances. But the Jamison Coal & Coke Co. has proved the economy and efficacy of compressed air for this purpose at its Mine 8 near Farmington, 8 miles west of Fairmont, Marion County, W.. Va., and the mining industry as a whole concedes its superior safety in gassy or dusty coal mines.The uses for compressed air in coal mining are now generally associated with such equipment as coal punchers, chain-breast machines, and to a lesser extent the ""radialaxe"" type of mining machines.Electricity has rapidly superseded compressed air for power in coal mines during the past 20 years; and in the last few years the general, and often unwise, use of electricity at the face region has taken on added impetus through the widespread use of mechanical loading equipment.Some of the unfavorable results of this increased use of electricity are shown in the growing number of mine explosions and fires of electrical origin. In the past four years 59 explosions of this type took the lives of 672 men, or 74.8 per cent of the total number of deaths from explosions were due to explosions of electrical origin.3In 1926, an explosion in Mine 8 of the Jamison Co. killed 19 men. The exact source of ignition was not determined, although it was definitely decided that it was of electrical origin and probably was at an electric coal-cutting machine.Prior to this disaster the company had done some experimenting with compressed-air-driven mining machines, and its Mine 9 had been completely equipped with air-driven chain-breast machines; a few of these machines were also in use in Mine 8. The explosion, however, gave impetus to the adoption by this company of compressed air for operating face equipment. The chain-breast machines were as satisfactory as electric machines of the same type; but the trend in the industry was toward faster cutting machines, which required less physical exertion on the part of the operating crews. A track-mounted machine of the arcwall type was found to be suitable for the conditions and system of mining, so that one of these operated by compressed air was developed by the Jeffrey Manufacturing Co. working with the officials of the Jamison Co.The first of these machines was installed in the latter part of 1926 and additional machines were delivered from time to time, until at present there are nine of them in the mine. Necessary improvements have been made, with the result that a fast-cutting, easily handled, efficient, and safe mining machine has been developed for cutting the hard Pitts¬burgh bed coal of the Fairmont field."

Oct 1, 1932

The Cooperative Research Centre for Mining Technology and Equipment (CMTE) is funded by the Commonwealth Government, by its mining research members Ñ the Universities of Queensland and Sydney and the CSIRO1, and by its industry members Ñ BHP Coal, RioTinto R&TD, Hamersley Iron, Mining Technologies Australia, Pasminco, Shell Coal, WMC Resources, Advanced Mining Technologies, and Aberfoyle. The Centre conducts work aimed at improving the competitiveness of the Australian mining industry. The current work is focused in four areas: new mining and drilling systems, geological sensing, automation, and equipment maintenance and reliability. This paper describes much of the work in these program areas that relates to metalliferous mining.

Jan 1, 2001

By Andrea Taurino

Innovation means implementing a new product or a product that has undergone significant improvement over time, in terms of method, form and performance. Innovation encompasses all the scientific, technological, organizational, financial and commercial steps that need to be taken to put it into operation. Innovation combined with research and development makes it possible to perfect the product with consistency over time. Taking inspiration from the bases developed by the Austrian economist Joseph A. Schumpeter back in 1911, Danieli came up with the concept of “Innovaction” – a combination of Innovation and Action, to refer to the development and advancement of various products for the steelmaking industry, including the loop laying head for wire rod.

Aug 17, 2017

By Arthur S. Dwight

THE last decade of the 19th century was a peculiarly interesting one in. the annals of American metallurgy, especially as concerns the lead and copper- smelting industries; and it may be interesting to review briefly one of the outstanding incidents of that period, the development of the mechanical roasting furnace. I shall not pretend, in these reminiscences, to give with absolute accuracy the sequence of events or dates, nor to present a complete history of the period, but shall seek merely to 'sketch a more or less impressionistic picture with some of the underlying facts and causes as the recollection comes back to me and then point out how the present-day practice grew out of those activities. My acquaintance with the developments in Montana was based on occasional visits and general collateral information, but in Colorado I lived through the episode and was of it.

Jan 1, 1921

By J. van Wijk

"Vertical material transport is one of the major challenges for the successful implementation of deep sea mining projects. The EU research project „Blue Mining” is focusing on sustainable solutions for deep sea mining operations, with one major goal being the advancement of Vertical Transport Systems (VTS). To investigate flow effects under realistic conditions, especially clogging effects, a 136 m high test facility for flow analysis in vertical transport has been constructed using available mining infrastructure. Tests are run in a closed circuit, using a system of downfall and riser pipelines connected to a compact sediment injection- and separation unit as well as the centrifugal pump. The riser is equipped with pressure sensors, as well as temperature sensors, flow meter, concentration meter and high speed camera to allow comprehensive analyses of the flow regime and behavior of transported material within the flow. Additional mobile measurement devices allow wear and tear analyses of pipe material. This paper focuses on the determining factors of the tests leading to the design as well as the installation and trial of the test facility itself and explains the used components and work principles. INTRODUCTION Since the 1970s several research projects had been conducted investigating in the possibility of deep sea mining. In recent times projects for deep sea mining operations have started again, considering the rising demand on natural resources, especially raw earth elements. Yet projects like the Nautilus project on the deposit Solwara 1 [1], or Japanese projects focusing on the region of Okinawa [2] and Chinese projects [3] planning on depths of “only” about 2,500 up to 3,000 m. Until now no economical deep sea mining project was realized, due to the enormous difficulties of deep sea environments. Vertical material transport is one of the major challenges for the successful implementation of deep sea mining projects, considering transportation heights up to 5 km. The EU research project „Blue Mining” is focusing on sustainable solutions for deep sea mining operations, with one major goal being the advancement of Vertical Transport Systems or VTS [4]. Critical parts of the system would be identified and investigated to deliver solutions and higher the technology readiness level to a level were planning of a pilot project can be considered. At first case examples for mining projects of seafloor massive sulfides (SMS, 1,600 m water depth) and manganese nodules (MnN, 5,000 m water depth) had been calculated on basis of economical frame conditions, such as planned production rates to be efficient. As depicted in Figure 1 two major possible systems had been used for comparison, airlift system and pump system, considering multiple pump stations or single pumps. Based on the results and comparisons for the calculated vertical transport systems critical components and flow effects had been identified."

Jan 1, 2018

By H. Allenius

Today, most requests for quotations force all bidders to follow the bid document to the letter. The choice is then made based on price since it is the only difference in technically identical offers. However, clients allow and even encourage suppliers to come up with alternatives. Overall economy again, is much more than low investment costs. Operation costs may affect the economy of a project far more than a million saved in investment. There is almost always the choice: Should we go for the cheapest solution or should we go for the most economical solution? We strongly recommend the study of the long-term effects on investments as they often surpass any apparent savings in capital expenditure. With high operating costs, time is never on our side. Almost all relevant inputs and outputs in a concentrator have a value that can be expressed in a suitable currency. Unit prices may differ substantially from one operation to the other, but everything has a price tag and globalization has made it possible to move both goods and services to almost any place in the world. Even a rather simple exercise can give a good indication on which process improvements are worth pursuing when investing in new systems or equipment. The ones that do not qualify, as money earners, will naturally appear as clearly. No ?rocket science? is required, just process knowledge, practical experience, an open mind and some common sense and the reward may be the difference of having a good or an excellent project. The model we have developed can be made as detailed as required, but we do not recommend too much detail, as it sometimes tends to distract work and obscure the important issues. Two different process solutions compared in a simplified example illustrate the importance of evaluating a project based on its long-term effects rather than focusing on the investment costs only.

Jan 1, 2014

By W. A. Selvig

EQUIREMENTS of montan wax for industrial use in the United States before World War II were met by imports, nearly all of which came from Germany. An important industry for extraction and refinement of this wax from certain brown coals had developed in Germany. At the beginning of the war, montan-wax imports were shut oft, and American industry was forced to rely largely on substitutes. Since the war, relatively small amounts have been imported from Czechoslovakia. Because of the shortage of montan wax at the close of the war and the fact that industry in the United States had to rely on foreign sources in the past, this investigation was started in 1945 to determine probable yields of wax from domestic lignite. Results of the investigation and the properties of extracted waxes are described in this report. Also included in the report are discussions of the occurrence and geology of lignite deposits of the United States from which samples were obtained for wax extraction and the petrographic composition of lignites, particularly in respect to those components that contribute to wax yields.

Jan 1, 1950

By Lionel Ryan

In 1996, the Dominican Republic operation of Falconbridge (Falcondo) developed a 5-year Process Control Plan in conjunction with the corporate Process Control group located in Sudbury, Ontario, Canada. This plan was further refined into an analysis of the areas of the highest potential economic return for the company with the reduction shaft furnace operation being the most promising. Historically, the reduction plant, which comprises 12 shaft furnaces, has been the bottleneck of ferronickel production. Since 1996 there has been a history of control development, and the current status is that all 12 furnaces are using advanced model-based multi- variable predictive control. The combination of advanced process control (APC), improved control system performance and improved process information management has resulted in an increased throughput of 6% per shaft furnace and a reduction in operating costs of 4.5 US cent/lb of Ni. This paper reviews some of the major milestones that have been achieved in this development Keywords: Advanced Process Control; Model Based Predictive Control; Connoisseur, Reduction Shatt Furnace; Nickel Laterite Ore; Ferronickel; MonitorMV

Jan 1, 2004

By Robert T. Davis

An award is a form of recognition given for superior performance in a special field of endeavor. Each year awards are given by the Joseph A. Holmes Safety Association and the National Safety Council to the coal-mining industry's underground and open-pit mines that have worked a specific number of man-hours without a lost-time injury. These awards have a dual significance in that they prove efficiency can be attained without injury to persons. Safety awards do not result from luck or good fortune but do result from sincere desire coupled with sufficient effort and cooperation to achieve a desired goal.

Jan 1, 1964

By Ronald H. Church

As part of the Bureau of Mines health and safety research program in strata control, a ground-penetrating radar (GPR) system capable of pene-trating approximately 10 ft into the mine roof has been devised to identify anomalistic conditions. The GPR system consists of a transmitter with carrier frequencies of 250, 500, and 1,000 MHz, utilizing a dipole antenna, and a receiver, consisting of a dipole antenna fed into a sampler with a time base housed in a storage oscilloscope. A computer was utilized for data acquisition and data processing. Data analysis by computer enhancement revealed recognizable return ra-dar signatures from the middle man rock and main roof of the test site. These stratigraphic anomalies can be cataloged for recognizable fea-tures, which from the past history of the mine may have been shown to create strata control problems. Early recognition of such features could lead to immediate corrective actions and result in the saving of lives.

Jan 1, 1985

By P. G. Clites

The Bureau of Mines developed techniques for induction melting of titanium in a split, water-cooled copper crucible. Calcium fluoride, which was used as an inert slag cover during melting, formed an insulating layer of solid slag between the ingot and the crucible wall. This thin layer of slag effectively insulated the ingot from the crucible and prevented the molten metal from shorting across the slits between adjacent segments of the crucible. The technique provides a means of melting loose titanium sponge and scrap and eliminates the need for fabricating a consumable electrode. This report describes the equipment developed and compares ingots produced from two varieties of titanium sponge, from titanium scrap, and from previously melted titanium with ingots prepared by vacuum-arc melting and electroslag melting. A melting scheme was also proposed and evaluated whereby loose titanium sponge was consolidated into a first-melt ingot for vacuum-arc remelting.

Jan 1, 1969

By M. Hagfors

When establishing an underwater testing site for the energy measurements of the explosives, the dimensions of the measuring pool have to be measured to find out what is the maximum weight for the test charge. Secondly one has to decide the distance between the pressure gauge and the shooting point. Thirdly the pool has to be calibrated because of the reflections of the explosions by measuring the bubble periods of the calibration charges. The calibration shots can also be used to estimate the minimum weight of the explosive charge for the reliable energy measurements by calculating the shock, gas heave and total energy values and their standard deviations.

Jan 1, 2007

"The Cooperative Research Centre for Mining Technology and Equipment (CMTE) is funded by the Commonwealth Government, by its mining research members — the Universities of Queensland and Sydney and the CSIRO1, and by its industry members — BHP Coal, RioTinto R&TD, Hamersley Iron, Mining Technologies Australia, Pasminco, Shell Coal, WMC Resources, Advanced Mining Technologies, and Aberfoyle. The Centre conducts work aimed at improving the competitiveness of the Australian mining industry. The current work is focused in four areas: new mining and drilling systems, geological sensing, automation, and equipment maintenance and reliability. This paper describes much of the work in these program areas that relates to metalliferous mining. Mechanized Rock ExcavationThe disadvantages of the drill-and-blast excavation method are widely recognized and the last half of the 20th century has seen mining companies and mining research organizations aggressively pursue technology to excavate rock by other means. As discussed below, despite considerable effort and large amounts of funding, the quest for mining’s “Holy Grail” has been unsuccessful in all but the weakest rock types.COMRO (the Chamber of Mines Research Organisation) supported by the South African gold mining industry, spent three decades and (probably) tens of millions of dollars developing prototype drag bits and, later, impact breaking machines aimed at the mechanized stoping of narrow, tabular reefs. This work has not yet produced a commercially-attractive mining system. Work continues in South Africa to mechanize these stoping operations although now the emphasis is on the use of diamond-wire sawing techniques. This work remains in the experimental phase.Both British Coal and Germany’s Bergbau- Forschung spent many years developing techniques trying to extend the range of rock types which roadheaders could cut economically. Again, although new knowledge was produced, it is difficult to claim that any new commercial mining systems emerged from this work."

Jan 1, 2001

By Xue Yang

Even though many approaches have been proposed for automated fault detection and diagnosis of Heating Ventilation and Air Conditioning (HVAC) systems, and advanced maintenance programs, such as preventive and predictive maintenance have been applied for the systems, issuing work orders for corrective maintenance is still a reality. Currently corrective maintenance still accounts for more than 55% of all maintenance programs in average facilities in the US (DoE, 2010). Indoor air related problems are especially important among corrective maintenance work orders. This paper provides details of a case study conducted to capture the workflow that HVAC mechanics follow, their rationale in diagnosis process and the information they typically refer to while responding to indoor air related corrective maintenance work orders. The general workflow for HVAC mechanics to complete such types of work orders was summarized into 5 stages, and generic information requirements recorded from the case study were synthesized. Initial findings show two main challenges in the industry for HVAC mechanics to get access to required information, which highlights the need for a systematic approach that would enable identification of such information applicable to a given context under which a work order has been generated and provide values of required information for HVAC mechanics to do sound diagnosis through integrated data repositories.

Aug 1, 2013

By Xun Zhang, Hang Qiu, Andrea R. Gerson4, Shaomin Lei, Yubiao Li, Yu Meng, Zhenyu Pei, Min Lin

Efficient separation of trace muscovite from the surface/interface of quartz grains was accomplished during oxidizing calcination and catalytic pressure leaching of the hydrothermal quartz. Experimental results suggest that 98.97% or more of the muscovite was separated when quartz sand was calcined at 900 °C for 5 h and then leached by hydrochloric acid and ammonium chloride solutions as substitutes for leaching agents containing fluorides. The chemical processing techniques show high selectivity in purifying quartz sand by transforming mineral muscovite into active structures during oxidizing calcination, and then dissolving the active substances during catalytic pressure leaching

By Ajit Godbole, Ping Chang, Ramakrishna Morla, Purushotham Tukkaraja, Shivakumar Karekal

This paper presents the results of a study on the optimum auxiliary fan location to control air recirculation in dead-end workings where diesel-powered vehicles operate. Investigations were conducted with various secondary fan locations from the dead-end crosscut and with the intake air quantities varied using different auxiliary fans to control air recirculation and diesel particulate matter (DPM).

Jul 1, 2023