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By A. H. Tousley

Current problems in the cement industry are discussed and suggestions for solving them by modernization are made. Cement facility modernization is discussed in considerable detail with examples illustrating before and after conditions. Itemized are the improvements realized in better working conditions, better efficiency, higher production, lower costs, and better community relations. These improvements are related to the overall profitability of the particular plant or facility.

Jan 1, 1972

The realization that there is a limit to our supply of domestic mineral and fuel resources, which have been taken for granted until recently, has stimulated the need for conservation and optimum utilization of the Nation's minerals, metals, and fuels-resources critical to our national economy. The mission of the Bureau of Mines is to develop new technology, improve existing technology, and disseminate information related to mineral resources and industries. Fulfilling the mission is necessary to insure a continuing, adequate supply of minerals and alternative supplies of energy from reliable sources at the lowest possible cost to society and the environment. Established in 1910, the Bureau of Mines under the Department of the Interior is the Federal Government's primary research arm in the mineral field. Since the transfer of the fossil fuels portion of the energy research program to the newly organized Energy Research and Development Administration (ERDA) in fiscal year 1975, Bureau research has been concentrated on increasing mineral production, decreasing energy usage through more efficient processing, and decreasing material losses caused by corrosion. Concurrently, research is being addressed to improved coal-preparation techniques, especially to expanding utilization of low-grade coals and coals difficult to beneficiate, which are essential for reducing the need for petroleum and natural gas supplies and for redirecting our energy consumption. Fluctuations in the availability of foreign sources of minerals, metals, and fuels due to political and economic variability among nations have necessitated intensified investigation into coal mining, uranium-ore processing, and geothermal energy sources-three alternatives that can help to alleviate the dependence of the United States on foreign sources of energy.

Jan 1, 1975

By T Day, I G. Robertson, G J. Lyman

"Various approaches are used in the industry for establishing procedures (sample mass estimation and method of subsampling) for sampling and analysis of gold ores. The key factors that determine the accuracy of the results that can be expected for a given set of procedures are widely misunderstood.Recent developments in sampling theory show that the estimation of the accuracy that can be expected for a given gold ore as a function of sample mass is actually a simple matter. For a given sample mass, the accuracy that will be achieved depends only on the grade of the ore and the range of masses of the grains of the gold in the ore. This, of course, demands that a reasonable estimate of the distribution or spread of gold grain masses in the ore be known. But this is something that should be known if the gold is to be efficiently recovered in the processing plant.This paper provides a simple explanation of the real facts about sampling of gold, either in the field or in the plant, and provides results for a number of cases of combinations of fine and coarse gold in an ore. The prerequisites for accurate gold sampling are:correct sampling with no loss of sample or contaminationsample preparation procedures that recognise the impact of the gold grain mass spreadpractical analysis of the sample masses required to provide acceptable accuracy.Issues of corporate governance are also discussed.Citation:Lyman, G J, Robertson, I G and Day, T, 2016. The Simple Facts about Sampling Gold Ores, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 159–172 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Frederick Biery

Outline ? Project Challenges ? Results from 100 recent projects ? What factors are driving the best and worst projects ? A look at recent mining projects ? Conclusions

May 1, 2009

By P Knights, M S. Kizil

Truck/shovel operations constitute 50 - 60 per cent of the cost of open pit mining operations. Mining companies, therefore, are constantly seeking to close the gap between actual truck/shovel productive capacity and maximum potential truck/shovel capacity. This paper analyses the performance of a mixed truck/shovel fleet in an open cut coal mine in Australia. It analyses operating delays, and proposes a novel graphical means of determining truck-limited or shovel-limited operations. A goal seeking algorithm is advanced in order to maximise truck/shovel match factors (MF) and hence optimise fleet productivity.

Sep 26, 2011

By James Pile

Since C.C. White introduced coalmine roof trusses in 1967. many different systems have evolved. Beginning in the mid 1990's, several types of bar/cable truss systems have been introduced. A new and innovative bar/cable truss recently introduced offers several advantages. By eliminating many small parts, and simplifying the installation, this new truss increases operator safely. In order to fully benefit from the new truss system, a closer look at the individual components and their interaction was undertaken to understand critical implications on preload and overall support capabilities.

Jan 1, 2004

Greater mining productivity requires a more efficient cutting process. The cutting force available from today?s mining machines has been optimized with respect to machine size and weight. Researchers have shown that when employing water-jet-assisted cutting, bit forces and drum torques can be reduced significantly, which may allow mining machines to become lighter and more efficient. The Bureau of Mines has initiated a program to develop a water- jet-assisted rotary cutting system using the conventional bit assisted by a directed water jet operating at moderate pressures (3,000 to 10,000 psi). This water-jet-assisted cutting system has the potential to improve cutting efficiency without increasing machine horsepower or water usage (beyond what is presently used for dust control) or requiring fundamental changes in mining practice. IR addition to improvements in productivity, other anticipated benefits of water-jet cutting include reduced generation of respirable dust, elimination of frictional ignitions, increased bit life, reduced fines, and fewer machine vibrations. The papers presented at this open industry meeting discuss the development of water-jet-assisted cutting technology and future application of this technology to a variety of mining techniques including roof drilling and longwall mining.

Jan 1, 1985

The Bureau of Mines is responsible for a broad spectrum of programs for meeting the diverse and changing mineral resource needs of the Nation. These programs are managed by the Director and two Deputy Directors, who formulate general policy and program direction from the Washington, D.C., headquarters. A senior advisory staff, consisting of the Chief Staff Officer, Chief Scientist, and Chief Mining Engineer, provides advice and consultation to the Director on a wide range of scientific and technical matters and acts on behalf of the Director to maintain liaisons with other government agencies, mineral industries, and professional societies. Bureau program activities are classified into two major functions: (1) Developing new and improved technology that will make the production and processing of minerals more efficient, safer and more healthful for mineral workers and the public, and more compatible with a quality environment.

Jan 1, 1979

By Michael J. Klishis

Accident rates continue to show that underground mining jobs areamong the most hazardous occupations in the United States and roof bolter operators continue to have one of the highest accident incident rates (MSHA, 1991) despite efforts by labor, government, and industry to reduce and eliminate work-related hazards. In the last two decades we have seen technical innovations such as the ATRS, and there has been an increased emphasis on hazard awareness through programs such as MSHA's REAP, but bolter operators continue to be injured and killed. Researchers at West Virginia University examined risk in the roof bolter's job and developed new approaches to accident and injury prevention. The study concentrated on the workers' job performance, machinery and the work environment to identify miner's risk and hazard exposure while bolting.

Jan 1, 1993

By Jerry J. Gray

Transportation charges for mineral commodity movements in western Oregon and western Washington were determined mainly by a stratified random sample canvass of producers. Total 1965 mineral production value for this area was $53.3 million; the cost or charge to move this production from the mine to the consumer or to the point of consumption was determined to be an additional $38.7 million. Thirty seven companies were contacted as a sample out of a total population of 349; the statistically expanded sample production value deviated 3.6 percent from that obtained by the Bureau's annual canvass. The agreement between the sample results and the canvass totals demonstrated the effectiveness of the sampling method for obtaining data with a predesigned level of accuracy. For comparison, the north-central Idaho and western Montana area was studied, A random sample experiment was designed, but because of the dominance of a few major companies, a random sample technique would have required more visits to producers than if only the larger firms were contacted. Eighty-four percent of the 1966 mineral value ($198.6 million) was accounted for by interviewing 27 firms out of a total population of 199. Total transportation costs or charges for the area were $26.7 million. The significant difference observed between the relationship of minerals production value and transport charges between the two areas investigated can be attributed to the difference in the minerals produced. The western Oregon and western Washington region is a nonmetals-producing area as opposed to the predominance of metals production in the Idaho-Montana region.

Jan 1, 1968

By D. G. Tisdale, W. Curlook, J. M. Toguri

"In this study, the vapour phase reduction of titanium tetrachloride conforms to the traditional Kroll chemistry, but employs argon as an inert carrier gas and requires a higher reaction temperature of 1150°C to 1250°C. A vapour phase reaction is advantageous because titanium is the only condensed phase present, and the metal can be collected free of magnesium or magnesium chloride, in marked contrast to the titanium sponge produced by the conventional Kroll process. The yield of metallic titanium from the reaction was determined as magnesium additions ranged from 36% to 168% of the stoichiometric requirement. Yields of over 99% were obtained when an excess of magnesium was present. Although the collection efficiency was low, metallic titanium was collected at the reaction site, where all other species were present as vapours. Magnesium and chlorine concentrations in the collected titanium were less than 0.3%.IntroductionA proposed method (Curlook, 1987) for titanium production has been investigated as an alternative to the conventional Kroll process (Kroll, 1940). The advantages of the new process include a simplified means of recovering the product metal, and a potential for lower overall energy consumption and greater product purity. A higher reaction temperature for the reduction of titanium tetrachloride results in a vapour phase reaction, rather than the conventional liquid phase reaction. This is the major conceptual difference between the proposed and the established (Kroll) processes.This study focussed on optimization of the process chemistry and briefly examined the issue of product deposition and collection. The reduction of titanium tetrachloride with magnesium, to produce metallic titanium and gaseous magnesium chloride:"

Jan 1, 1997

By Wilbur I. Duvall, S. L. Windes, Leonard Obert

"Previous investigations, too numerous to be listed in entirety, have been performed to determine the physical properties of rock. When considered according to their objectives, most of these investigations can be grouped as follows: First, the geologic group (1,2),4/ in which the purpose was to obtain information on the physical properties of the rocks that make up the earth's crust. Particular emphasis has been placed on the determination of the elastic constants--that is, Young's modulus, the modules of rigidity, and Poisson's ratio – as these quantities determine the propagation characteristics of seismic waves. Second, the structural properties group (3 - 11), in which the physical properties of architectural or monumental stone, concrete and aggregate rock, road blocks (cobblestone), and the like were desired. The tests have been quite general and include, besides the elastic properties; the compressive and tensile strength, and the toughness, hardness, and weathering properties of many types of rocks.To .a lesser degree, investigations have been carried out to determine the physical properties of mine rock. A few reports (12 - 14) present data on the crushability and grindability of mine rock, and a large number of papers discuss grinding and crushing procedures and methods of analyzing the data (for example, see references 15 - 17). Some of the latter group also have given the results of tests on mine rock; however, comparatively few include an adequate petrographic description or information on other physical properties of the rock. A few papers,(18 - 22) have reported studies of the strength of rock specimens in respect to the strength of parts of mine structures, such as pillars, roof, arches, etc. Other papers (23 - 26) have discussed investigations on such subjects as primary and secondary crushing, diamond and pneumatic rock drilling, explosive breaking and shattering of rock, rate of drifting and miring, and other allied problems. The majority of these reports have given no more than a cursory, description of the rocks and have included no statement regarding the physical properties. When statements have been given regarding the physical properties, they have usually referred only to isolated tests, making correlations between variations in the physical properties and variations in the .test under consideration difficult, if not impossible. Some reports have included handbook values on such characteristics as the crushing strength, hardness, and toughness. This practice is not satisfactory, because these values are usually given for col¬lective types of rocks, such as granites, limestones, and marbles, and it is known that the variations of the physical properties within these groups is often larger than the differences between the groups."

Aug 1, 1946

By Alan Alhadeff

Why is mediation being hailed as the wave of the future? The high cost of putting on a trial, over-crowded court calendars and long trial delays have resulted in what prominent attorneys and leading jurists are calling a litigation crisis. In no segment of the legal world are these pressures greater felt than in the trial of the serious construction case. Furthermore, the siege mentality of both the plaintiff and defense bar often leads to a reluctance by either side to make the first reasonable offer for fear of showing weakness. Attorneys operating in the serious construction case arena express concerns that there exist insufficient opportunities for the parties to meet, tell their stories, and negotiate settlement prior to the eve of trial. Mediation, by opening lines of effective communication and encouraging meaningful settlement negotiation, has proven to be a very effective antidote to the litigation crisis.

Jan 1, 1990

By Za-Chieh Moh

This paper presents a summary of the current pile foundation practice in Taiwan. Constructions of driven piles, drilled shafts, and barrette foundations are reviewed. This paper also briefly summarizes the pile works of four major construction projects in Taiwan, namely, Hsin-Ta Power Plant, Taichung Power Plant, Taipei Transit Systems, and Taiwan High Speed Rail.

Jan 1, 1996

By Ilpo O. Auranen

Background: Mines of today are moving ever increasing tonnages of rock. The new ore bodies tend be of lower grade and located deeper in the earth?s crust. The industry?s focus to overcome this ?deeper but poorer? ore problem has traditionally been to lower the costs by increasing the scale of mining. This has resulted in an ever increasing size of mining equipment like drills, loading shovels, dump trucks. The main focus has been in reducing the cost per ton of mining. This cost focus has often resulted in increased waste rock dilution and more ore losses. From costs to value: Waste rock dilution means waste rock in the concentrator feed. It?s value in open pit mining is equal to the value of ore it replaces. In underground mining, waste rock dilution?s value is equal to the value of ore it replaces added to the costs of mining it. It is commonly accepted that waste rock dilution in open pit mining ranges between 5 and 20% and in underground mining between 5 and 40 % . In a typical large open pit mine ore value is from 20 to 60 USD per ton and mining costs are 1 to 3 USD per ton. One percentage point reduction in waste rock dilution represents savings corresponding to about 20% of total mining operation costs. The difficulty of reducing waste rock dilution comes from the complicated nature of the ores. Accurate ore waste-border detection has not been possible due to excessive costs. Core drilling combined with geochemical lab analysis is the most accurate method for locating ore waste borders. However, it is also expensive and time consuming, which is why it is often combined with somewhat lower cost methods like sampling drill cuttings from blasting drill holes or from reverse circulation drills and analyzing them in a laboratory. The main drawback with these methods, in addition high costs, lies in the sampling accuracy and in the quality control of the whole process when a large number of samples have to be handled manually. In every mine it is possible to halve waste rock dilution by using new on-line analysis technology .

Oct 1, 2009

By Launa Mallett

This paper introduces a method for teaching workers to communicate necessary information when giving or receiving emergency warning messages. Research has shown that when an emergency occurs, people may not get the information they need to take appropriate action. Interviews conducted with 48 underground coal miners who had escaped mine fires revealed that the warning information provided was inadequate. In some cases, sufficient information was not provided to the endangered miners. At other times, miners failed to ask for information they needed to plan and execute effective escapes. Researchers from the NIOSH Pittsburgh Research Laboratory have been studying the content of emergency warning messages and have developed an emergency communication protocol. A training intervention that presents the protocol and related mental cues is being evaluated for effectiveness in improving the content of emergency messages. In this paper the protocol is presented and the training package described. The evaluation procedures and a summary of the analyses conducted to-date are also provided. The training package was developed for use with underground coal miners, but could easily be modified for emergency communications training in other settings.

Jan 1, 2000

On 26 August 1971, the Bureau of Mines, through the Spokane Mining Research Center at Spokane, Washington, approved initiation of the evaluation of oscillatory energy toward enhancing flow of polymer into shale. The effort was an outgrowth of work performed under Bureau of Mines Contract H0210055, "Feasibility Study of Surface Impregnation equipment for the Chemical Stabilization of Coal Mine Structures," wherein feasibility of the impregnation concept was expressed and the detailed design of a machine for impregnation of coal mine roofs with polymer (under static pressure head) accomplished. Under these efforts, the potential enhance¬ment of polymer uptake into the shale thru superposition of oscillatory energy on the static impregnation pressure was suggested. A proposal for investigation of this phenomena entitled "Feasibility Study of the Application of Oscillatory Energy as an Aid to Afford Chemical Stabilization" was presented to the Bureau whereupon a three month program for initiation of investigation was approved.

Jan 1, 1972

By L H. G McClean

Diversity, equity and inclusion are often cited as ‘important priorities’ by mining companies and industry organisations in their public presentations and reports, but is the minerals industry really making strides forward? The mining industry is the least gender diverse industry in Australia (WEGA, 2023). Women make up just 22 per cent of the mining workforce and mining has a gender pay gap of 15.1 per cent (WEGA, 2024a). Only 8 per cent of the CEO roles are female and 20 per cent of boards have no female members (WEGA, 2023, 2024a). Gender diversity, equity and inclusion is a highly topical issue with the recent release of the Respect@Work report, Western Australia Parliamentary Inquiry as well as the publication of company specific workplace culture reports and the national legislative changes to implement a positive duty for organisations to prevent sexual harassment in the workplace. This comes at a time of a skills and labour shortage in the minerals industry as well as declining geoscience study and participation. This is a perfect storm for our future workforce. Governments, industry associations, networks and companies are developing and supporting initiatives to make strides towards equity and inclusion, with some shining examples on both an industry and company level, but the dial is only moving slowly and, in some ways, going backwards. Every company is unique, but every company can review and support gender diversity, equity and inclusion. Actions to progress gender parity could include establishing a clear company position; ensuring that this position is cascaded throughout the company with appropriate training; reporting and reviewing gender participation as well as supporting positive workforce initiatives and a positive culture with a people-centric issues reporting process. At the industry level, there are clear gaps in the support for gender diversity and inclusion including a national voice and ‘one-stop-shop’ to support women in the industry and provide resources. Recommendations include improved co-ordination and collaboration of support for women as well as improved promotion of the suitability (and safety) of the industry for women. The new independent organisation, Women in Mining and Resources Australia (WIMARA) has the objective to address the challenges of gender diversity and inclusion as well as foster co-ordination, co-operation and collaboration between the different stakeholders and state or territory groups and amplify reach. To deliver the future workforce that the minerals industry needs, the time is now for the industry to make some giant leaps for womankind.

Sep 1, 2024

By D. Campos, J. M. Macedo, S. Chadwick

The incorporation of low cost technology transfer to increase the ability of locals to acquire and maintain long term employment are key ingredients for sustainable industrial development. Alcoa’s Alumar plant on the island of Sao Luis is the largest and most modern refinery/smelter complexes in northern Brazil. The plant has one of the most advanced Environmental, Health, and Safety management process in the aluminum industry. Technical assistance, training and financial support were made available to Alumar to address social sustainability issues. Through several programs led by employees on a voluntary basis and applying intensive and extensive training programs, Alumar has enabled local people to develop skills on agriculture and land management, wastes minimization, small business development and administration, all based on sustainable development and social responsibility concepts.

Jan 1, 2004

By D. Komljenovic, E. Lafontaine, J. Paraszczak

Availability of the production equipment used in underground mines has a substantial impact on production costs and, thus, on mine profitability. Appropriate collection of pertinent data and information, as well as use of adequate performance measures and their analyses, can help mine operators identify cost-effective opportunities to improve equipment availability. This paper presents study results aimed at reviewing and analyzing means and measures used to quantify equipment availability and its contributing factors (reliability, maintainability and maintenance support) in several Canadian underground mines. It overviews sources, as well as quality and quantity of relevant data and information, and examines performance measures and their definitions, as applied to surveyed mines. Problems concerning data acquisition and meaningfulness of the performance measures are discussed. The paper concludes with some suggestions and recommendations concerning several aspects of equipment availability assessment. Evidence suggests that the latter may become a more useful tool for mine operators in their efforts to reduce production cost.

Jan 1, 2008