Search Documents

By Cem Şensöğüt, Özer Ören, Yaşar Kasap

The mining sector, which has an important place in terms of raw material and energy supply, is referred as a sector with one of the highest fatal accidents in comparison with other sectors. In this century, where occupational health and safety awareness has increased, it is important to review the past accident statistics and to determine the current deficiencies by using the information in the inventory. In this study, the Malmquist total factor productivity index (MPI) has been utilized to investigate the changes in the work accidents occurring in the Western Lignite Corporation (Turkey), where underground and surface production methods are applied, and to determine the measures to be taken. According to the results obtained, both the decrease in production amount and the increase in the number of accidents caused inefficiencies during the period in concern due to the expected 10-year economic life of the mechanized system operating in the underground production panel that came to an end in 2007 and the flooding took place in early 2017. Compared with the underground operations, it has been determined that production can be carried out at the appropriate scale despite the heavy working conditions encountered due to the changing climatic conditions and the progress of production in the surface operations.

By Mark Aylmore, Guy Deschenes

"Increasing pressure are motivating the gold mining industry to develop a substitute to cyanide for leaching gold. This effort in mainly based on the high toxicity of cyanide and on the lack of efficiency of cyanide in the treatment of mildly refractory gold ores (sulfides and pre-robbing). Consequently, in only a few years, consortia have been created to elucidate and implement a new technology. The most promising lixiviant that has been selected to replace cyanide is thiosulfate. This paper will present a critical analysis on the latest developments in thiosulfate leaching and illustrate the potential and limitations of the technology with experimental data. Finally an assessment of the cost and performance of thiosulfate leaching relative cyanidation will be evaluated.INTRODUCTIONConcerns regarding the toxicity of cyanide and inability of cyanide solution to effectively leach some carbonaceous gold ore or mild refractory gold ores have made the gold mining industry evaluate alternative lixiviants to leach gold. This concern has been heightened recently by the cyanide spill at a mine in Romania, which devastated a 250-mile stretch of the Danube River and its tributaries, and the environmental damage at Ok Tedi mine in Papua New Guinea. Some countries and locations have prohibited the application of cyanidation to recover gold, such as, California and Colorado States, Japan and Turkey etc.There are several potential non-cyanide lixiviants (Sparrow and Woodcock, 1995) for gold extraction, such as thiosulfate, thiourea and halogen. A pilot feasibility test (Marchant and Broughton, 1987) had suggested that thioureation might result in acutely toxic byproducts even after treatment. Scientists of Swedish Academic of Sciences reported that thiourea is a carcinogen. Halogen is also a pollutant to the environment. Thiosulfate leaching appears to have very good potential as an effective and less hazardous procedure for gold and silver extraction from auriferous ores. In addition to being much less toxic and relatively cheap, it forms a stable anionic complex with gold but is less reactive to other metals, for instances, copper and carbonaceous materials, in comparison with cyanide."

Jan 1, 2001

By William I. Busenbark, Elmer C. Newman

At Bingham Canyon, the world's largest open-pit copper mine, annual grease consumption is in the neighborhood of 109 000 kg (240,000 lb), all of which was 544 (120-16) purchased, warehoused, and distributed in 54-kg (120-1b) and 180-kg (400-1b) drums. While perhaps a menial and mundane chore, grease distribution shows on the ledger as a significant expense item. To improve labor and cost performance, Kennecott maintenance engineers undertook a study to find the most direct method for moving multi purpose grease (MPG) from the refinery to the point of final consumption. What they found was a direct vendor system for hulk grease so simple and flexible that long-established drum distribution is being phased out in favor of the newer method throughout 75% of the operation.

Jan 9, 1977

By J. H. Zietsman, S. Maharajh, J. Muller

In the chlorination process for TiO2 pigment production, blends of titania feedstocks such as ilmenite, synthetic rutile (SR), natural rutile, upgraded slag, and chloride-grade slag are reacted with coke and chlorine at a temperature of around 1000°C to form TiCl4 (the main product) and other waste metal chlorides. The TiCl4 is the main feed material for the TiO2 pigment-making process. Feeding different titania materials to the chlorinator affects the amount of coke and chlorine required for the process, the amount of waste generated, waste disposal costs, the amount of TiCl4 produced, and bed build-up rates. These factors influence the value of the feedstock. Generally, a higher TiO2 feedstock is more valued since less waste is generated and less reagents are consumed. To quantify the impact of different feedstocks on the chlorinator, a techno-economic model was developed to describe the chlorination process and estimate process variables at steady state. This paper describes the development of the model and studies in which the model has been used to quantify effects of using different feedstocks.

Jan 1, 2015

Australia is the world's leading producer and exporter of mineral sands. Despite increased production from some other countries in recent years, Australia maintained its No.1 position in 1988 among world producers of mineral sands concentrates. Production of the titanium minerals -- ruffle, ilmenite and leucoxene, as well as synthetic ruffle -- by the seven companies currently comprising the Australian industry increased in 1988 in response to continuing strong demand for feedstock by the pigment industry. Production of co-product zircon remained at the 1987 level, reflecting declining zircon grades. Exports of mineral sands concentrates increased in 1988; export earnings exceeded $300million. Prices for mineral sands concentrates are now at a historical high and, assuming that the world economy remains strong, real prices should continue to trend upwards in the short term. Exploration in the Eneabba-Cooljarloo region and the Scott River area, both in WA, the Murray Basin, Vic, and the central Queensland coast area, has identified substantial resources of heavy mineral sands. These discoveries have reversed the trend of the early 1980s of falling resources of mineral sands. In 1988, BMR estimated that economic demonstrated resources (EDR) of ilmenite, rutile, zircon and monazite combined was about 72.8 million tonnes. However, a substantial portion of the resources on the east coast are frozen as a result of environmental considerations. The proportion of mineral sands concentrates processed in Australia increased with the commissioning of two new synthetic rutile plants; Australia is now the world's leading producer of synthetic rutile (total capacity 272000 tonnes), most of it for export. Australia's two TiO2 pigment producers have both increased capacity, lifting national capacity by some 70p ercent to over 120000 tonnes/yr. As part of the expansion one producer converted from the sulphate to the chloride process. Other new pigment plants are being proposed for the future.

Jan 1, 1989

By J. Sikamo, A. Mwanza, C. Mweemba

"The Zambian copper mining industry as we know it today had its genesis in the 1920s. Consistent private sector-driven investment in the industry over a period of over 50 years in exploration, mine development and operation, development of minerals processing facilities, building of infrastructure for pyrometallurgical and hydrometallurgical processing, with attendant support facilities, including building of whole new towns, resulted in copper production rising to a peak of 769 000 t in 1969, providingover 62 000 direct jobs. The industry was nationalized in 1973 and remained in government hands for just over 24 years. During this period, the industry experienced a serious decline in production levels, reaching the lowest level in the year 2000 when production was 250 000 t. An average of just under 2000 jobs were lost every year in the 24-year period, reaching just over 22 000 direct jobs in 2000.Following the return of Zambian politics to pluralism and liberalized economic policies, the government decided to privatize the mining industry. The process started in 1996 and by the year 2000 all the mining assets had been privatized. The new investors embarked on serious investment to upgrade the assets and to develop greenfield mining projects. Fourteen years later and after more than US$12 billion investment, production levels increased year-on-year to a peak of 763 000 t in 2013 with direct jobs reaching 90 000.This paper discusses the impact of the mining industry in Zambia on the economy in areas such as employment, support for other industries, direct contribution to the national gross domestic product (GDP), foreign exchange earnings, and social amenities. The paper also focuses on the performance of the mines during these periods vis-à-vis mineral availability, mineral grades and complexity, new technologies, and human capital. This is looked at particularly in the light of current challenges the industry is facing. Suggestions are proposed on how the industry can be nurtured to continue being a major driver for the Zambian economy and a major player in the international copper mining business."

Jan 1, 2016

Jan 1, 1998

By G. I. Gritsko

In this paper we consider the elements of a distributed information geomechanic monitoring system which is used in computerized mine planning and mining operations control. The automated system is a technical means of geomechanic monitoring, as a complex system of regulated observations, estimation and prediction of geomechanic state of rock mass and workings during underground mining of coal deposits. Geomechanic monitoring at coal mines and the automated system execute data collection, analysis and calculations of geomechanic situation in the panel during planning, development and carrying-out of mining operations for ensuring geotechnical stability of underground mining.

Jan 1, 1996

THE slide-rule, as a quick and convenient instrument for performing approximate calculations, is steadily growing more and more into favour with the engineer, and results obtained by it are considered close enough to enable him to satisfactorily dealwith a considerable portion of his work. To the surveyor, however, whose ordinary computations must be as precise as his measurements, the present makes of rule are insufficient, except for a very narrow margin of the scales and for rough work. Few will carry the rule when they can clearly see that it is unreliable for general routine, and the careful surveyor is inclined to look askance at those who do use it, recognizing the temptation there undtmbtedly must be to push it into work that the log book should be called upon to treat. From the fact that a surveyor's duties take him on the surface in all weathers, and underground in many wet and uncomfortable places, where the manipulation of a book of mathematical tables becomes both awkward and patience-trying, an efficient slide-rule must offer the mbst transparent advantages. Again, a surveyor being specially trained to read divided scales quickly and accurately, the slide-rule must commend itself as an apt addition to his outfit.

Jan 1, 1912

By M. S. Miller

With prevailing assumptions that plentiful domestic coal reserves will be available for meeting our Nation’s expectations for on future low emission, coal-fired power plants, major government funding in Clean Coal Technology, and Carbon Sequestration Programs continues to be aggressive. However, after more than a decade of cutbacks in funding for domestic coal-related programs and personnel, there is a growing concern that adequate quantification and qualification of our Nation’s coal reserves is increasingly being compromised. This paper will define the growing concerns and dichotomies that continue to increase, and address the decreasing number of fossil fuel mapping and assessment programs by Federal and State programs.

Jan 1, 2004

By R. V. Ramani

"A computer simulation model of a dragline has beer developed for the study of alternative dragline deployment schemes for varying geological and mining conditions. In this paper, the mathematical aspects of the model, the input data and output results are discussed. An application of the model to a coal mine in eastern Kentucky is presented.IntroductionDraglines are very productive machines. To extend their operating ranges, they are operated in several modes such as advance benching, key cut, extended benching and pullback. Unfortunately, these variations result in low machine productivities. Appropriate methods to operate these machines must be developed on the basis of detailed analyses of dragline performance under varying geological and mining conditions. There are several standard engineering procedures for the selection of dragline, and design of a dragline pit (Ramani, Iroegbu and Manula, 1976). However, the complex interrelationship which exists among equipment, methods and natural conditions can be quantified only through orderly and systematic experiments.Computer simulation is well suited to studying these types of equipment selection and method layout problems. Several alternatives can be analyzed in a relatively short time by the modification of input variables. Also, the application of computer simulation models can significantly reduce the manpower and cost required for such analysis."

Jan 1, 1985

By Axel Studeny

Geomechanical-numerical methods are an established tool for planning of underground excavations worldwide. By describing the interaction between heterogeneous layered strata and support elements it is possible to determine their suitability. The German hard coal mining industry has more than twenty years experience in investigation and using these parameters to carry out numerical calculations. Today, nearly all excavations (shafts, pit bottoms areas, bunkers, coal faces, development drivages, gate roads etc.) are calculated by geomechanical-numerical tools in combination with empirical planning methods. A high accuracy of planning results, which is a special requirement in the German coal industry with its deep-level longwalls, bedded and weak surrounding strata and multiple seam mining layouts, depends on the extensive calibration of the numerical models, which is achieved by: 1) Taking a large number of underground measurements with empirical evaluation. 2) Carrying out physical modeling. 3) Using the characteristic features of the installed support elements. This paper compares the planning approach used for multiple and single seam mining and presents the advantages of this planning tool. The main focus is on the feasibility of rockbolting as the sole means of roadway support for multiple seam mining operations, though the paper will also look at how the costs can be improved by using a low bolting density in single seam layouts.

Jan 1, 2007

By A T. Spathis

The 11th International Symposium on Rock Fragmentation by Blasting (FRAGBLAST 11) was held in Sydney, Australia, between 24-26 August, 2015. The 93 papers, including six keynote presentations, covered exciting and practical topics in 20 sessions within 12 themes. Just fewer than 300 delegates from 27 countries attended. Four workshops were conducted on the weekend prior to the symposium, with three field visits after the symposium to Sydney region quarries, the Hunter Valley coal mining region, and the Kalgoorlie gold mining region. Delegates had the opportunity to visit the exhibition areas that showcased the latest products, software, hardware and systems in blasting technology. The keynote addresses were held in plenary sessions and set the tone for the parallel sessions that followed. They spanned the dynamics of the mining industry, the detonics of explosives, the interaction of stress waves and fracture mechanics in fragmentation, wall control blasting, and the importance of education and engineering for full process optimisation.

Jan 1, 2015

By Johnston W. H

MINING operations in the Waihi mine began, under the present proprietorship in the year 1889. Previous to this, and as far back as the year 1880, the presence of reefs in the Martha Hill had been known, and surface working on a small scale had beencarried out, without any great measure of success. The only method of treatment in use at this time was the old system of light stamps, amalgamating tables and berdans, and recovery by this method being low, little margin for profit was left, so thatthe property in these days was not considered of great importance and work on the area was only carried on spasmodically by different owners.On the transfer of the leases to the present company, calcining, dry crushing, and hot pan amalgamation was adopted as the method of treatment, and this system was continued till the more modern cyanide process was introduced and applied. As themethods of treatment and gold-saving became more efficient with the application of more modern and scientific processes, the importance and future prospects of the mine became more and more pronounced, and mining on a larger and more comprehensive scale was gradually established.As in the case of ore treatment, mining methods in the early stages were not as far adv.anced as the adopted practice of today, and numerous shafts, levels close together in vertical height.

Jan 1, 1912

By S. K. Mitterecker, T. Hofbauer, F. Baerhold

"Acid regeneration is a very important process step in each acid leach circuit. It is required to recover dissolved metals and HCl from spent leaching acid. Andritz Metals presents its recently commissioned spray roast pilot plant. The facility is now available for testing and demonstrating acid recovery or metal oxide production which is a requirement in several flow sheets under development for the mining and specialized oxides industries. Results from pilot test campaigns are reported here. We are currently focusing on a nickel ore leaching process, which requires both a feasible iron control and acid regeneration step. In addition, we disclose the results of a magnesium ore and aluminium recycling test campaign conducted in our pilot plant facility.INTRODUCTION Hydrochloric acid regeneration is widely used in the steel industry to regenerate spent pickle liquors into hydrochloric acid at a typical concentration of 18 wt.%. Andritz Metals (formerly known as Ruthner) has built more than 200 acid regeneration plants worldwide (Andritz Metals brochure). As technology leaders Andritz also has vast experience with specialty metal oxide plants, producing metal oxides such as aluminium oxide (Al2O3), magnesium oxide (MgO), nickel oxide (NiO), cobalt oxide (Co3O4) and mixed oxides from metal chloride solutions (Baerhold F., Lebl A., Starcevic J., 2006), (Jedlicka, H., n.d.), (Ruthner M.J., Krischner H., 1973), (Ruthner Ind. Planungs AG, 1967). Hydrochloric acid leach circuits have been developed and proven in the industry for many years. Examples of industrial applications are: synthetic rutile production (TiO2) (Walpole E.A., Winter J.D., 2002), Quebec Iron and Titanium’s UGS process (Patoine M.-C., De Mori A., Borowiec K., Coscia C., 2002), magnesium and potassium production (Priemer H., 1973) and Goro Nickel (Vahed A., Colton D.F., Duterque J.P., Karner W., Baerhold F., 2004), (Taylor A., 2013). One of the critical process steps in developing a hydrometallurgical process is acid regeneration, as it is an economic requirement to recover both the dissolved metals and acid (commonly HCl) from the spent leaching solution."

Jan 1, 2016

By H W. Wu

The objective of this paper is to examine some modern forms of auxiliary ventilation fabric ducting with streamline design fittings and the efficiency of construction practices. The most dynamic form of auxiliary ventilation is a moveable fan and ducting, which is easy to install and uses light weight fabric. The porous nature of some ducting construction results in leakage and loss of efficiency. Flexible fabric ducting is primarily associated with metalliferous mining and industrial material quarrying. Some applications are found in coal in stone/rock development and with use of dust scrubbers.Forcing auxiliary ventilation systems employing circular fabric ducting have been examined. Leakage of air from ducting is affected by ducting material and construction methodology (such as welded or sewn), quality of installation, number of joints, total length, pressure differences between the inside and outside and diameter. The best ducting system with welded construction can have up to four times less leakage as compared with some systems with sewn construction. It is also evident that the sewn type ducting will deliver less air to working faces and require more fan power, hence higher operating costs to run when connected to the same fan.A case study has also been undertaken to compare predicted operating costs of auxiliary ventilation systems connecting various types of ventilation duct fittings. The study also assesses the technical importance of streamline design with low aerodynamic resistance to reduce the shock losses of the duct fittings. It was found that the system connected with streamline designed fittings is able to provide some power cost savings and deliver more air compared with the system fitted with conventional fitting pieces.Using a ventilation ducting system with a lower leakage and frictional characteristic represents a sound solution to new challenges faced by the industry for increasing demand for better quantities and quality of air delivered to working faces; this is due to higher production schedules and stricter mine health and safety regulations within the Australian mining industry.CITATION:Wu, H W and Gillies, A D S, 2017. A comparison of auxiliary ventilation systems and their predicted operational performances, in Proceedings Australian Mine Vent Conference 2017, pp 207–214 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By Vern Pfannenstiel

Jan 1, 2005

Editor’s note: As usual, the June issue features an industrial minerals review. And some thanks are in order. Thank you to the industrial minerals annual-review editor, to the technical committees chair and vice chairs and to the authors of the individual commodity profiles. Jim Norman of GeoTrans Inc. is the industrial minerals annual-review editor. Lucy McCartan, US Geological Survey, was the chair of the SME industrial minerals technical committees. She also served as the vice chair for agricultural minerals. Other technical committee vice chairs were: •Gary Tomaino, Specialty Minerals Inc., ceramics and refractory materials. •Srinivas (Vas) Veeramasuneni, US Gypsum, chemical raw materials. •William Langer, US Geological Survey, construction materials. •Vanessa Santos, Independent, fillers and pigments. •Richard Berg, Montana College of Mineral Science and Technology, specialty minerals. Their help makes possible this June industrial minerals issue. On behalf of the readers, the editors thank them.

Jan 1, 2002

By AIME AIME

THE John Fritz Gold Medal for 1929 was presented to Herbert Hoover at the Executive Mansion on April 25, at a luncheon given by Mr. Hoover to present and past members of the Board of Award, preceding medalists, and presidents and secretaries of the American societies of Civil, Mining and Metallurgical, Mechanical, and Electrical Engineers. The presentation party of forty engineers which gathered at the White House, from all parts of the United States, was made up of past presidents of the four senior national engineering societies that established the John Fritz Medal and included five men who had received the medal in previous years. These former medalists were Edward Dean Adams, J. J. Carty, J. Waldo Smith, Elmer A. Sperry and Ambrose Swasey. This medal is the highest honor bestowed by these four national engineering societies, having a membership of 60,000. It is awarded not oftener than annually for "notable scientific or industrial achievement, without restriction on account of nationality or sex." In accordance with custom, the award to Mr. Hoover was made tentatively and without announcement in October, 1927, and was formally con- firmed and announced one year later.

Jan 1, 1929

By Lester G. Morrell

AGAIN in 1963, as in nearly every year since 1946, the Canadian mineral industry has established a new national record in value of mineral production. The 1963 estimated total value of $2,976 million is 5 percent higher than the 1962 value of $2,845 million.2 As in previous years, metals made up more than half the value of total production. For selected years since 1949 the category percentages and total value are as follows: [ ] Crude petroleum, Canada's most valuable mineral product, accounted for 21 percent of the total value of minerals in 1963. In descending order came nickel 12 percent, iron ore 10 percent, copper 10 percent, gold 5 percent, and uranium 5 percent. Asbestos accounted for 5 percent, sand and gravel 4 percent, and cement 4 percent. The complete list of Canada's mineral products includes more than 50 basic commodities.

Jan 1, 1964