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By C. Pritchard

John Marks said in his acceptance of the Hartman Award in 2008, “I guess that without the occasional complaint, your mine is probably over-ventilated” (Marks, 2008). Miners are seldom in this situation and spend much of the time trying to find enough air to keep an operation running. With examination, there are usually changes that can be made to increase the efficiency of ventilation systems. Mine ventilation air is a costly commodity, especially by the time it has been heated or cooled and moved to the bottom of the shaft and through the mine airways. Modifications that result in surplus mine ventilation air could bring financial and environmental benefits. Some issues mine operators have needed to address recently are increased airflow requirements to dilute diesel particulates in metal and nonmetal mines, to ventilate reserves that are deeper, hotter, and further away from fans and shafts, and to meet demands from increased production. This paper discusses successful methods to find additional usable air when there is no extra ventilation capacity. Most of the options presented in this paper are useful for metal/ nonmetal operations but some may be applicable to coal as well.

Jan 1, 2009

By William Gleason

"There are signs that the commodity downturn that has battered the mining industry for the past five years is beginning to ease up. As the dust begins to settle and mining companies begin to take stock of the battle, Newmont Mining Corp. will be one that is standing strong with just a few scrapes and bruises thanks in large part to the leadership of president and chief executive officer Gary Goldberg and his right hand man and chief operating officer, Chris Robison.As he closes in on retirement (for a second time) Robison, a third-generation miner from Nevada, took time to speak with Mining Engineering about a 33-year career in which, among other things, he is credited with not just helping Newmont survive the turbulent times but with steering the company to a safer, more productive and more profitable heading.“I think we did it better than anyone else,” Robison said when asked how the company fared during the past five years. “We didn’t talk about it a lot, we just put together a strategy and we delivered.”What Newmont, the world’s second-largest gold mining company by production, delivered since Robison took the position of chief operating officer in 2013 are improvements in costs, porduction, projects and safety.Operating under the mantra of “live within your means,” Robison was pulled out of retirement from Rio Tinto and into a challenging situation at Newmont. The price of gold was in a nose dive from a high of nearly $58/g ($1,800/oz) and heading to levels closer to $38.60/g ($1,200 oz).“Newmont is a big ship that can’t be turned, but has to be steered,” said Robison. “We recognized that we had to set a new course. The direction the ship was going was great for $1,600 to $1,800/oz gold but we were chasing ounces.”Like the rest of the gold mining sector before the falling gold prices, Newmont was focused on volume and was looking for gold wherever it could be found. The slogan at Newmont in 2011 was “7 million ounces a year by 2017.”When Robison came on board it was a different reality.“We had to begin focusing on value over volume as the cornerstone of Newmont going forward,” he said."

Aug 1, 2016

By L. J. Heaslip, J. M. Toguri, T. R. Meadowcroft, R. L. Addinall

"""Pilot Plant Operations"" is a final-year core course given to the Metallurgy and Materials Science students at the University of Toronto. This course involves a laboratory study of an industrial project at an industrial site. Details of this program are discussed and reviewed after eight years of experience. IntroductionEducators in the field of Metallurgy and Materials Science have long agreed that ""hands-on"" experience is an important component in the education of metallurgical engineers. This philosophy is reflected in the undergraduate curricula of most metallurgical schools. The major problems encountered with laboratory-associated courses are the requirements for equipment, space and funds for both purchase and maintenance of equipment. For example, consider an exercise in crushing and grinding treatment in a mineral processing laboratory. Such operations require the handling of tons of material and often equipment of large size. The problems of storage of ore, methods of handling and maintenance of equipment are a few of the concerns facing the department. Considering that metallurgical departments at universities are, in general, relatively small, the support to purchase and maintain largescale equipment becomes an annual budgetary concern. In reality, universities today are not geared to operate mini-pilot plant equipment, either in terms of space or personnel.For the above reasons, in 1972an undergraduate core course called ""Pilot Plant Operations"" was introduced to the fourth year curriculum in Metallurgy and Materials Science at the University of Toronto. This course consists of I to 2 full weeks (8 hrs per day) of pilot plant laboratory study at an industrial site on a project of mutual interest with the industrial organization whose facility is being used. The first 5 years of the program were carried out at the pilot plant facility at the Ontario Research Foundation; Stelco's Research Centre in Burlington, Ontario, was used for the last 3 years. The nature of the projects undertaken during the 8-year period is shown in Table 1."

Jan 1, 1980

Granduc lies near the Alaskan border in British Columbia, about 600 miles (960 km) north of Vancouver. Prospecting in the area must take place in the short summer months of fog and rain because the winter is bitter cold, with snowfall up to 960 inches (24.4 m) accompanied by avalanches. Despite these difficulties, the mineral ized area was discovered in the 1920's. By 1956, Newmont Mining Corporation had developed mineable ore reserves estimated at 32,500,000 tons of 1.93% copper. Newmont and ASARCO, in a joint venture, then began development of the ore body, which was partially covered by glaciers. It was apparent a concentrator could not be built at the mine site where overland access was impossible due to the weather conditions and the terrain. Years of engineering studies of all possible access routes finally dictated the driving of an 11 mi long (17.6 km) tunnel passing under three glaciers and three mountain ranges to the nearest feasible concentrator site at Tide Lake. Even then, a mountain road subject to an average snowfall of 800 in. (20. 3 m) had to be built 32 mi (51 krn) from the concentrator through Alaska to Stewart, British Columbia, the nearest port. At Stewart, which is located at the head of a fjord 120 mi (192 krn) from the Pacific Odean, a fully equipped marine terminal was built. The tunnel, the lifeline between mine and mill, was to be driven from both ends; however, in 1965, an avalanche occurred at the Leduc portal, killing 26 crew members and wrecking much of the camp. The tunnel was then driven from one heading adjacent to the concentrator site at Tide Lake, a distance of 53,744 ft (16,381 m) to a point under the ore body. The remote location, type of terrain, and bad weather made supply of crews, equipment, and construction materials difficult; but in spite of these extremely adverse conditions, the tunnel crews set many world records. Mineralization throughout the ore zone is generally uniform in grade and composition and is primarily chalcopyrite and pyrrhotite associated with pyrite. Mining is mainly by sublevel caving. After blasting, rubber-tired load-and-haul equipment moves from level to level by means of an internal connecting ramp system on a 15% slope. At the gathering haulage level, 15-ton bottom-dump cars deliver the ore to a 600-ton pocket equipped with a Hudson "Rock-Flo" dump. The bottom of the ore pocket forms the feed chute to the primary

Jan 1, 1978

By M S. Tuohy

Since the independent review of fatal accidents in the mining industry carried out by Dr Sean Brady (the ‘Brady Review’), High Reliability Organisations (HROs) and their operating principles have been discussed across the Queensland mining sector. HROs are organisations said to consistently avoid serious failures, reliably delivering their organisational objectives despite operating in environments characterised by high levels of inherent risk and/or operational complexity. HRO concepts have previously found application in other similarly hazardous industries to mining. However, as Hopkins (2009) pointed out, HROs ‘are very elusive creatures that inhabit the realm of theory more than the real world’. The Queensland Resources Council (QRC) with support from the Commissioner for Resources Safety and Health initiated a review of how HRO principles can be translated to the mining industry. The review was conducted by Noetic, an Australian management consulting company that specialises in hazardous industries, including mining and metals, and has prior experience applying HRO theory.

May 5, 2022

By J Joy, A Bye, G V. Kizil

This paper presents an application of the newly developed risk-cost-benefit (RCB) framework to support risk management decisions for the selection of wall monitoring technologies at an open cut mine site. The RCB framework quantitatively assessed the risk of unstable slope-induced wall failure and its impact on both loss of life and coal recovery. The RCB framework was utilised in the selection of an optimum group of risk-controls to effectively manage the risk of wall failure to ensure safety and optimal production occurred. The RCB framework incorporates mathematical modules that integrated RCB calculations and risk-control effectiveness assessments to determine the risk reduction and financial impact of the examined safety initiatives.This paper provides an overview of the five-staged RCB framework, incorporating the RCB decision support tools, RCBGEN (Risk-Cost-Benefit Generator) and RCEMETHOD (Risk-Control Effectiveness Method), and demonstrates its application to slope stability risk management at the case study site. The RCB charts are designed to display a balance between risk, cost and benefit for easy interpretation by decision makers to support the objective selection of an optimum suite of risk-controls. The RCB analysis revealed that a combination of ævisual inspections, automatic extensometers and radarÆ for fast- and slow-wall failures with structure were sufficient to reduce the probability of loss of life (PLoL) to the æModerateÆ zone as defined by the Australian Geomechanics Society (AGS, 2007) for the case study site. The new framework presented in this paper provides a method to effectively determine the suitability of risk-controls and supports industry efforts to reduce risk to as low as reasonably practicable (ALARP).CITATION:Kizil, G V, Bye, A and Joy, J, 2012. Risk-cost-benefit analysis of early warning technologies impact for wall failure risk management in surface mines, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 55-64 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

Nautilus Minerals and Neptune Minerals are betting that the next great metals rush will take place more than 1,500 m (5,000 ft) below the sea. Nautilus is the first company to commercially explore the ocean floor for gold and copper seafloor massive sulfide (SMS) deposits. Its main focus is the Solwara 1 Project, a polymetallic copper, gold, zinc, silver deposit that is under 1,600 m (5,200 ft) of water off the coast of Papua New Guinea in the western Pacific Oceans? Rim of Fire. Nautilus Minerals, in a joint venture with Placer Dome (now Barrick Gold), began its exploration of what would become the Solwara 1 area in 2005 with side scan sonar and dredge sampling. The dredge and grab sampling confirmed the grade tenor of earlier sampling by scientific research programs. The 45 dredge samples aver-aged 10.8 percent copper, 3.7 percent zinc, 224 g/t (6.5 oz/st) silver and 13.7 g/t (0.4 oz/st) gold. Nautilus has since staked out more than 300,000 km2 (115,800 sq miles) of tenement licenses and exploration applications in the waters off Papua New Guinea, Fiji, New Zealand, Tonga and the Solomon Islands. That is an area about the same size of the United Kingdom. Interest in Nautilus and its projects has grown tremendously since its inception. The company is now listed on the Toronto Stock Exchange. It has raised more than $300 million and spent more than $23 million on exploration. The company has gained the backing of mining majors such as Teck Cominco, Epion, Anglo American and Barrick Gold. It is positioned to become an emerging producer in 2010. Teck Cominco recently agreed to exercise share purchase warrants to acquire three million additional common shares of Nautilus at a price of US$15 million. This will take Teck Cominco?s shareholding to approximately 7.2 percent of the issued shares. Teck Cominco will conduct and manage a ship-based exploration program that will run in addition to the exploration that was already planned for 2008.

Jan 1, 2008

The Anglo Platinum Mogalakwena North concentrator was one of the first three hard rock mineral processing applications to utilise a HPGR circuit in preference to a SAG milling circuit. This was driven by the extreme competence of the ore that had given rise to throughput issues on the original South Plant. Despite more than adequate capacity and performance of the individual comminution units, the circuit has struggled to obtain full design capacity. A thorough review of the integrated performance of the circuit revealed a wide range of bottlenecks and underutilised parts of the circuit arising from design issues. Interestingly, the major opportunities lie in materials handling issues and mismatch of loads about the circuit. This paper presents the high-level outcomes and the associated opportunities, and is pertinent to all HPGR circuit designs.

Jan 1, 2012

By Faustino Roel

AMONG the problems confronting the mining engineer in Mexico in recent years, labor conflicts have come to occupy s prominent place. Each day they have become more serious and frequently have caused- the ruin of companies. It is therefore necessary for the engineer to understand the Federal Labor Law, the rights and obligations of companies and of their workmen, and the reasons for conflicts; to keep in mind the expense which may be caused companies; and to endeavor to avoid difficulties as far as possible. Our labor legislation is primarily to protect the workman and the constant tendency of the tribunals, including the Supreme Court of Justice, is to support the work- man in his demands against employer$, even at times granting him more than he asks, with no limit other than the economic capacity of the company to com-

Jan 1, 1937

By Robert Cameron, Colin Ashton, John MacNeil, Leo Piciacchia

"The in pit dam construction and utilities relocation, known as the East Mine Corridor Relocation (EMCR) project, was developed to extend the life of the east side of the Base Mine pit by two veal's. This will result in the recovery of an additional 80 million barrels of oil and delay expenditures associated with the opening of the North Mine by two years. To accomplish this, a large in pit earth structure was required to provide a new embankment foundation for relocating a public highway, four powerlines, a natural gas back-up pipeline, a substation, and a conveyor train. This structure would also he required as a temporary dam 10 contain mature fine tails on the west side until mining is completed in the east mine corridor area, that will then be filled with fluid.The in pit dam, known as The Highway Berm, is 2.5 km long, 63 m high and has 42 million m3 of engineered soil added to the already existing end-dumped soil volumes. To complete the design and construction of a structure of this magnitude, in the very short time frame of two-and-a-half years, presented many new challenges. The main challenges faced were: designing while construction was ongoing; designing without the use of clay cores or sand filters; using relatively non-select overburden material; proper dewatering and base preparation; changing from construction of 50 m high spoil piles to a high specification construction operation; compacting lifts with heavy haulers; constructing during the winter; and monitoring movement of the structure with satellites."

Jan 1, 1995

By Ulises Crossa Archiopoli

We describe a technique that allows rapid imaging of the thermal diffusivity of the sample by a modified photo-thermal technique. The thermal diffusivity in hardened steels strongly correlates to the hardness. Hence in a noncontact manner and with optical microscope resolution, a 2D map exhibiting the crystallographic phases and hardness of the sample can be retrieved. Two almost collinear laser beams scan the surface, one as a modulated pump and a second as a CW probe. The deflection of the probe carries information on the thermal expansion of the sample and with it, on the thermal diffusivity. It is shown that a single determination of the time delay of the modulation of the probe beam can be used to retrieve the thermal diffusivity.

Jan 1, 2010

By G. S. Rice

To those concerned in attaining greater safety to life and incidentally to property in coal mining, the meeting of representatives of the national mine safety research organiza¬ tions of the principal coal-producing countries, which was called by the Safety in Mines Research Board of Great Britain at its experimental station near Buxton, should have deep significance. It is notable, first, because it meant the friendly cooperation of countries not many years ago engaged on either side in the great World War; and second, because of the remarkable degree of agreement in the essential fundamental factors and methods of attaining greater safety in coal mines when it is considered that the questions were approached by different paths and that the applications dealt with widely differing natural conditions and national points of view. Varying views, of course, were held as to the relative importance of certain factors, but the differences were of detail rather than of principle. When the meeting adjourned it was unanimously agreed that such meetings should be continued annually and that the greatest benefit was to be derived by close cooperation in the exchange of data. Belgium, France, Germany, Great Britain, and the United States were represented by one or several members of the respective national research organization. It is of interest to note that this research work in Belgium, France, and Germany is supported directly by na¬ tional organizations of mine operators or owners but placed under a scientist appointed by the respective Government, thus giving the work official standing. In Great Britain the work is carried on by a Government board, consisting of persons connected with the coal¬ mining industry or in mining research, appointed by the Secretary for Mines, to direct the work of research of the Mines Department. It does not, however, come under its inspection service. Its work is supported by a penny-a-ton tax on output of coal. In the United States the mine-safety research work is directly supported by the Federal Government.

Dec 1, 1932

By L. W. Blau

PERHAPS the most important event f or exploration geophysics in 1940 was the publication of three textbooks : "Geophysical Prospecting for Oil," by L. L. Nettleton ; "Exploration Geophysics," by John J. Jakosky; and "Geophysical Exploration," by C. A. Heiland. The literature had grown so bulky, and such a long time had elapsed since the publication of the texts by Ambronn and Eve, that treatises covering exploration geophysics comprehensively in all its branches and giving literature and patent references were sorely needed. This need has been satisfied admirably in these textbooks, and geophysicists owe the authors a debt of gratitude. In 1940, geophysics came of age. A conference on applied nuclear physics was held at Massachusetts Institute of Technology from Oct. 28 to Nov. 2. Several papers on geophysical subjects were presented at this meeting. Geophysical activity has decreased in all parts of the world except perhaps in Canada where, under the stimulus of the war's increased demands, prospecting for oil has increased. However, even there the war has had a seriously adverse effect on prospecting for ores and upon the promotion of new properties, although activity in producing and near-producing mines has been stimulated.

Jan 1, 1941

By D. W. Alexander

Researchers from the U.S. Office of Mine Safety and Health Research (OMSHR) of the U.S. National Institute for Occupational Safety and Health (NIOSH) completed field trials during coal mine rescue contests using simulated gas detectors in place of placards. The gas monitor simulator (GMS) devices replaced static, paper placards to deliver gas concentration data. Eleven teams were observed during the field contest, which was approved by the Mine Safety and Health Administration (MSHA). GMS devices were given to three team members (the captain and both gasmen). Observation of teams revealed that team members changed behavior by acknowledging and sharing information more often while using the GMS. As a result of this research, it has been demonstrated that under the existing contest format, the newly developed GMS device may be used with no adverse impact on team contest performance. Furthermore, when GMS technology advantages are used, contest realism is improved. In the future, competency assessment may be incorporated.

Jan 1, 2012

By AIME AIME

THE official opening at the 134th general meeting of the Institute was held on Oct. 6, but it was prefaced by two round table conferences on Oct. 5. The open-hearth group held the fourth of their semi-annual conferences at the William Penn Hotel, devoting the morning session to discussing a paper by R. L. Cain on the "Manufacture of Forging Steel by the Open-hearth Process," and the afternoon to discussing P. H. Shaeffer's paper on the open-hearth charge. At the Bureau of Mines, a round table conference on the combustibility of coke was held on Tuesday morning, and the afternoon was devoted to a similar conference on the testing of coke. The formal opening session of the meeting assembled in the Music Hall of Carnegie Institute at 10.30 a. m. Graham Bright, chairman of the Pittsburgh Section; called the meeting to order and presided. President Taylor welcomed the visiting members and guests to his home city and reviewed briefly the advancement of mining in the past half century during which, for ex- ample, the coal output had increased from 53,280,000 tons to 523,357,000 tons per year. He emphasized the important part Pennsylvania played in mining and brought out the principal changes that had taken place in methods. In part, his remarks were as follows: The centennial year, 1876, found the coal business of. this country, as a whole, producing 53,280,000 tons, of which amount the bituminous mines of this State yielded 24 per cent. In 1925, this country produced 523,357,000 tons of coal, of which Pennsylvania produced 24 per cent.

Jan 1, 1926

By W. D. Smith

It has been 5 years since the writer left the Philippine Islands and while in that country his chief work did not lie in this field, though he has visited all but one of the localities mentioned in this article. The principal field studies relating to oil were M de by his colleague, Mr. Wallace E. Pratt. The writer's investigations ealt with the general stratigraphy and paleontology of the Philippines. with the exception of the investigations made by Mr. Pratt and the writer very little information on this subject is available. A number of geologists in the employ of large oil companies have visited the Islands from time to time but, following the general rule, the public has scarcely ever been permitted to learn anything of the results. The writer is indebted to the Bureau of Insular Affairs, Washington, for late information regarding recent legislation in the Islands relating to petroleum. All the known oil seeps, petroleum residues, such as ozocerite, and natural-gas emanations are associated with Tertiary sediments. The chief seeps and most promising prospects are located as follows: 1. Bondoc Peninsula (lower end), Tayabas Province, Southeast Luzon. 2. The west coast of the island of Cebü from Alegria north to, and perhaps beyond, Toledo. 3. Central Mindanao not far from Lake Lanao. 4. The ozocerite veins on the Island of Leyte in the northwestern part in the vicinity of the town of Villaba. 5. Natural gas from some deep wells in Tertiary shale formations on the eastern flank of the Cordillera and extending out under the plain on the island of Panay. The first mention in geological literature, to the writer's knowledge, of gas or petroleum in the Philippines is found in the description of the Island of Panay by the Spanish geologist, Abella, in the year 1890. In 1898, an oil well was being dug on the estate of Smith Bell & Co., an English concern, near the town of Toledo on the west coast of Cebu. In

Jan 1, 1921

By James A. Schneider

The successful installation of long piles driven into very dense sands relies on the occurrence of the reduction in local friction with increased pile embedment, a phenomenon known as ?friction fatigue?. The underlying mechanisms controlling friction fatigue are poorly understood, with some design methods including an adjustment for the influence of pile diameter while others do not. This paper back calculates the installation resistance of 0.356m to 2m (14in to 78in) diameter open ended piles driven into very dense sands using wave equation analyses. Cone penetration test data are used to link soil properties to installation resistance. The study illustrates consistent interpretation of a variety of case histories of open ended piles driven in very dense sands using newly developed analysis techniques and normalized parameters. Results provide information on methods for incorporating friction fatigue into drivability studies as well as a discussion of mechanisms related to pipe pile installation resistance in sandy soils.

Jan 1, 2010

By Wilhelm Flesch

THE object of development work in the field of gasification is to find a process by which all' fuels, regardless of their individual properties, can be gasified economically. This paper describes the development of the Winkler process. The economy of the gasification process depends not only on the degree of the gasification effect but also, to a decisive extent, on the costs of fuel, production, and installations. Fig 1 shows the relation between fuel costs and gasification efficiency for various types of fuels. Since the fuel cost in the gasification of coke amounts to two thirds of the price of gas, and the thermal unit in brown coal costs only one third of what it costs in coke, it is easily seen how profitably cheap fuels can be gasified, especially if these fuels require minimum preparation and gasification is done in the vicinity of the mines. These possibilities were a great advantage of the Winkler generators, which were installed 20 years ago in the central German brown-coal fields and, at that time, were without rival for the gasification of finely divided fuels. In the Winkler generator (Fig 2), crushed and ground solid fuels were, for the first time, successfully gasified with oxygen and steam on an industrial scale. Unlike the usual processes formerly employed on an industrial scale, this gasification, which proceeds continuously in the glowing, seething fuel bed, makes only extremely low demands on the fuel. The fuel no longer has to be in lumps and abrasion-resistant, but must be capable of reaction and must be fed into the generator in a grain size of 0 to 8 mm. Brown coal or bituminous coal, or their low-temperature cokes, can be gasified in the Winkler generator. Large plants using fuels are operating on an industrial scale in Europe and in Japan. Table 1 shows the results obtained by gasifying these, fuels in Winkler generators. The thermal efficiency of gasification, which is the relation between the calorific value obtained in the gas produced and that of the fuel consumed, gives no indication of the quantity of steam generated in gasification. The generation of steam in the waste-heat boiler of the Winkler generator adequately-covers the steam consumed in gasification. To obtain effective gasification in the Winkler process, combustible mate-

Jan 1, 1953

By R. W. Stahl

Methane, a highly explosive gas evolved during the coal-formation process, is one of the hazards of mining most difficult to overcome. It is retained between particles of coal and entrapped in strata overlying and underlying the coal beds to a degree dependent upon the permeability of the enclosing strata. Considering that methane might be encountered at any time during the mining of coal, attempts have been made through the years to minimize the sources of ignition at coal-mine faces, such as the introduction of permissible electric equipment, the prohibition of smoking and open lights, and the development of safer explosives. The sparks created when mining-machine picks contact sandstone or iron pyrites2/ constitute one source of ignition, always recognized as a possibility but never greatly emphasized in the United States until recently, when ignitions began occurring with rather alarming frequency and in widely scattered coal-producing areas.

Jan 1, 1956

By Yi Luo, Hua Jiang

A roof bolting drilling operation in an underground coal mine can expose the operator to a high concentration of respirable coal and crystalline silica dusts (smaller than 10 µm). Overexposure of high-level quartz dust for a roof bolter operator can lead to the development of silicosis in as little as three years [1]. This study proposes a drilling control algorithm for the bolt hole drilling process. This algorithm can be integrated into a current drilling control system on the roof bolter machinery and is expected to reduce the generation of respirable dust while enhancing the energy efficiency of the roof bolter machine. In addition, the drilling efficiency and bit condition can be evaluated while drilling based on the real-time feedback parameters. This capability enables the algorithm to ensure the drilling is performed under a relatively high energy efficiency with less respirable dust generation and to avoid drilling with an excessively worn bit that can cause bit clogging or steel buckling failure.