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By M. C. Leverett, M. E. True, W. B. Lewis

This paper states the theory underlying the design of two kinds of dimensionally scaled models of parts of idealized oil fields. One of these simulates an oil well and its surrounding sand for a distance of 16 ft. radially from the well. The other model simulates linear flow through layered sands. Construction and operation of the models are described and typical data are given. The unique features in the design of the models are: (I) the treatment of the permeability-viscosity quotient as a single variable and (2) the use of previously reported experimentally developed relations between relative permeability and saturation and capillary pressure, saturation, porosity, permeability and interfacial tension. The models at present simulate flow of oil and water only, through unconsolidated sands. They are superior to unscaled models, which may give rise to erroneous conclusions. The models are designed to study the desirability of various methods of well completion and the effects of various factors on recovery of oil from layered sands. Introduction Recent work on the fundamental behavior of flowing mixtures of fluids in sands has resulted in the development of some new theory in this field, much of which has been presented in previous papers.l-4 However, the application of this theory to the behavior of oil wells or oil fields has proved too complicated for ordinary mathematical techniques, except in very highly simplified cases. A practical solution to this problem appears therefore, to lie in the use of dimensionally scaled models of elements of oil fields. The object of this paper is, first, to present the theoretical and experimental basis of the design of such models, and, second, to describe their construction and operation. Experiments now under way on the models already built will yield material for other reports, which will be devoted to interpretation of the results in terms of oil-field behavior. So far, simple dimensional models of two kinds have been built and are being operated. These models represent different parts of an idealized oil field but obey the same underlying theory. The only fluids represented are oil and water, since certain questionable approximations are necessary for gas-liquid systems. General Theory Dimensional models have been used in other fields for a long time, and their theory is adequately given in the literature. 5 Here, it suffices to state that each physical element entering into a dynamic relation may be given a definite description in terms of three fundamental, but arbitrarily chosen, dimensions. These usually are mass, length, and time, symbolized here by the small letters m, I, and t. Two systems are said to be dimensionally similar or dimensionally scaled if for each element in one system there is a corresponding element in the second system and the ratios of the numerical magnitudes of corresponding elements are constant for all elements of the same dimensional type.

Jan 1, 1942

By W. B. Lewis, M. E. True, M. C. Leverett

This paper states the theory underlying the design of two kinds of dimensionally scaled models of parts of idealized oil fields. One of these simulates an oil well and its surrounding sand for a distance of 16 ft. radially from the well. The other model simulates linear flow through layered sands. Construction and operation of the models are described and typical data are given. The unique features in the design of the models are: (I) the treatment of the permeability-viscosity quotient as a single variable and (2) the use of previously reported experimentally developed relations between relative permeability and saturation and capillary pressure, saturation, porosity, permeability and interfacial tension. The models at present simulate flow of oil and water only, through unconsolidated sands. They are superior to unscaled models, which may give rise to erroneous conclusions. The models are designed to study the desirability of various methods of well completion and the effects of various factors on recovery of oil from layered sands. Introduction Recent work on the fundamental behavior of flowing mixtures of fluids in sands has resulted in the development of some new theory in this field, much of which has been presented in previous papers.l-4 However, the application of this theory to the behavior of oil wells or oil fields has proved too complicated for ordinary mathematical techniques, except in very highly simplified cases. A practical solution to this problem appears therefore, to lie in the use of dimensionally scaled models of elements of oil fields. The object of this paper is, first, to present the theoretical and experimental basis of the design of such models, and, second, to describe their construction and operation. Experiments now under way on the models already built will yield material for other reports, which will be devoted to interpretation of the results in terms of oil-field behavior. So far, simple dimensional models of two kinds have been built and are being operated. These models represent different parts of an idealized oil field but obey the same underlying theory. The only fluids represented are oil and water, since certain questionable approximations are necessary for gas-liquid systems. General Theory Dimensional models have been used in other fields for a long time, and their theory is adequately given in the literature. 5 Here, it suffices to state that each physical element entering into a dynamic relation may be given a definite description in terms of three fundamental, but arbitrarily chosen, dimensions. These usually are mass, length, and time, symbolized here by the small letters m, I, and t. Two systems are said to be dimensionally similar or dimensionally scaled if for each element in one system there is a corresponding element in the second system and the ratios of the numerical magnitudes of corresponding elements are constant for all elements of the same dimensional type.

Jan 1, 1942

No one process, product or effect of the minerals sector can be viewed in isolation when addressing sustainable development. Meaningful assessments of the minerals sector require that its processes and production are drawn together in a generic framework that gives a holistic view of its performance and progress. Lifecycle Assessment is increasingly accepted as an appropriate means of constructing such a framework. It is a step beyond using the simplistic concept of the triple bottom line of social, environmental and economic performance to drive and communicate sustainable development. However, fundamental questions need to be raised about the scope and purpose of lifecycle assessment, such as what effects and performances should be assessed, for whom should they be assessed, and what performance indicators should be used and how should they be selected. The principles of eco-efficiency, industrial ecology, The Natural Step (TNS) and other pertinent philosophies and initiatives driving mineral sector sustainable development are outlined to support a lifecycle stewardship vision for the minerals sector. Articulating this vision through a holistic lifecycle indicator system showing inputs and outputs, natural partnerships, effects on community, environment and economy facilitates recognition of problems, opportunities and partnerships that can be usefully pursued.

Jan 1, 2002

By Cole NH

Substantial savings in terms of project time, cost, and financial viability can result through the expert involvement of independent financial advisors in the early stages of any mining project's preparation. This role is not confined to project financing, financial modelling, valuations and corporate finance advice, but may in the early stages be much more strategic in nature, covering a wide group of subject areas. A number of separate examples and case studies are outlined, which show the manner in which financial advisors can be effectively used. The benefits arising from involving an additional professional team with the project group must be offset against the separate and additional cost factors involved.

Jan 1, 1986

AXTAT is a computerised system developed by the Western Australian Department of Minerals and Energy in conjunction with the local mining industry for recording and retrieving information about fatalities and work related injuries. Since its inception, the system has gained considerable recognition by consistently demonstrating its usefulness as a tool, not only to the Department, but for the entire industry nationwide. AXTAT has played an important role in the continuous improvement process in management of occupational health and safety in the Western Australian mining industry with gains in both human and financial terms, by regularly providing timely and accurate statistical feedback on fatalities and lost time injuries to industry.

Jan 1, 1996

By Donald J. Olson, Thomas J. Lutzenberger, John Ramage

The North Shore Inline Interceptor, Phase IA tunnel is a 8,550-meter (28,000-ft) interceptor tunnel currently being constructed by Traylor Bros./Frontier-Kemper, Joint Venture, using a 9.8-meter (32-ft - 4-in) diameter Robbins tunnel boring machine (TBM). This tunnel is being driven in Silurian age dolomite approximately 91.5 m (300 ft) below ground surface. Significant water inflows were encountered when the tunnel drive penetrated the thinly-bedded Waubakee Formation. Flow increases approaching 0.75 cu m per min per 30 m of tunnel (200 gpm per 100 ft) have occurred in this formation. After driving approximately 2,285 m (7,500 ft) of tunnel (200 m full face in the Waubakee Formation), total flows exceeded 12 cu m per min (3,200 gpm) with about 5.7 cu m per min (1,500 gpm) entering the tun¬nel from the 200 m (600 ft) of exposed Waubakee Formation. Additional water control measures consisting of increased pumping capacity, increased water treatment capacity, surface grouting ahead of the tunnel, grouting ahead of the tunnel face and panning to improve the working environment for installation of tunnel support, were implemented to deal with the large water inflows. Currently (January 24, 1989), 3,400 m (11,000 ft) of tunnel has been driven, total water inflows are in the range of 11.7 cu m per min (3,100 gpm) with only 6.8 cu m per min (1,800 gpm) inflow from about 1,220 m (4,000 ft) of tunnel driven full face through the Waubakee Formation.

Jan 1, 1989

By J. T. Michalak, H. W. Paxton

The recovery of the initial flow stress of poly-crystalline iron is characterized by a) a logarithmic time dependence; b) an increasing activation energy with increasing recovery; c) an increased ?,ate and fraction of recovery with decreased temperature of deformation; and d) an increased rate with increased deformation. Isochro)ml studies of the recovery of single crystals revealed more sluggish recovery. The original flou3 stress of single crystals could be regained by recovery anneals at 800"or 900°C. ThE great majority of the theoretical treatments and experimental studies of strain-hardening have been concerned with the close-packed lattices.' Very little effort has been expended on the bcc structure so that the theory of work-hardening of this lattice is essentially nonexistent. The limited amount of experimental data resulting from the direct studies on silicon-iron,2 low-carbon steel,3 and purified irons4"7 does not as yet permit a detailed analysis of the strain-hardening. Studies concerned with the effects of annealing following deformation have been few in number," have been somewhat limited in extent, and have had the disadvantage of using irons containing a substantial impurity content. The present research was undertaken to augment the limited knowledge we have of the characteristics of a bcc metal as regards strain-hardening and recovery from the strain-hardened state. The recovery of the flow stress has been employed since it was felt that the stress associated with the hardened state gives at least a fair qualitative description of the state of the imperfections causing the hardening. The study was concerned primarily with the recovery of flow stress following strain-hardening of polycrys-talline, zone-melted iron as a function of the amount of deformation, the temperature of deformation, and the time and temperature of the recovery anneal. A limited investigation of the recovery of the initial flow stress of single crystals of this same material as a function of the recovery temperature was also conducted in conjunction with the Lambot X-ray technique." MATERIAL The zone-melted iron used in this investigation was obtained through the courtesy of the American Iron and Steel Institute and Battelle Memorial Institute. The analysis, as given by the supplier indicated a maximum impurity content of 0.02 wt pct excluding those impurities listed in Table I. (The actual impurity content is very probably less than this since detection limits were considered as the amount of a particular impurity level.) Also listed in Table I are the interstitial impurity contents of the iron at various stages of experimental work indicating that these im-

Jan 1, 1962

By H. Kurama

In this paper, utilization of fly ash as a value added product in areas such as novel materials, waste management, fillers and agriculture is reviewed with the aim of helping the expand of the usage of fly ash and reduce the environmental and economic impacts of disposal. The used unburned carbon benefication/treatment methods such as low temperature combustion, froth flotation, partical size classification and electrostatic separations to remove unburned carbon particles from fly ash are also discussed.

Jan 1, 2006

Martha Mine is an open pit gold-silver mine, located within the township of Waihi, 150km southeast of Auckland and is operated as a joint venture between Normandy Mining Ltd. 67 %) as Manager and Otter Gold Mines Ltd. (33%). The deposit was historically mined, by underground methods from 1888 to 1952, producing 5.5 moz of gold and 30 moz of silver, from 11 mt of ore. The current operation began in 1988, producing, to June 1999 - 867,245 oz of gold and 5.5 moz of silver from 9.5 mt of ore. The licensed reserves were due to be mined out by late 2000. Consents were granted in December 1998 to allow the expansion of the operation through to 2007 accessing an additional 7.5 mt of ore at 3.4 gpt Au and 26.0 gpt Ag for 800,000 oz of gold and 6.4 moz of silver. The key elements of the expansion are: 1. Pit enlargement 2. Upgraded crushing and material handling facilities 3. Construction of a second tailings storage facility 4. Upgraded water treatment capacity 5. Increased operating capacity This paper presents an update of expansion activities to date.

Jan 1, 1999

By M. A. Pipke, C. M. Brown

The semiautogemus grinding circuit at the Utah Mines Ltd., Island Copper operation, located on Vancouver Island, British Columbia, is described. Since startup of the operation in 1971, grinding circuit throughput has been progressively increased from the initial design rate of 90 000 (99,000) to the current average 45 000 t/d (49,600 stpd) of porphyry copper ore. Key developments ad modifications in operating and maintenance practice that have contributed to this increase are reviewed.

Jan 1, 1987

By Chugh Y. P

A generalized void diffusion model for subsidence prediction has been developed based on theoretical concepts and physical principles. The general form of the model is a three-dimensional differential equation. With a few assumptions on the characteristics of overburden strata overlying typical room-and-pillar mining or longwall mining systems, specific solutions for the differential equation were obtained. A brief description of these solutions and their applications in the United States and China are presented in this paper.

Jan 1, 1992

By Surendra K. Mishra

The principles of dewatering fine coal has been examined in terms of solid- liquid separation. It is noted that the physical and physico-chemical properties of the particle-liquid system influence the rate and degree of moisture removal. Using postulated models the roles of polymers, surfactants and other physical means as dewatering aid are discussed.

Jan 1, 1988

By Yumi Nakashima, Setsuo Maeda

Vibration magnitude and frequency of the z-axis vehicle seat are time-variant, which are influenced by not only vehicle vibration characteristics themselves but also road surfaces, speeds and the human body. There is little in the current reporting about evaluating and analyzing automobile seat vibration that focuses on the time-variant. Yaguchi et al.1 has proposed a method to evaluate automobile seat vibration that is based on judgments using a subjective mental state. Their method focuses on the time-variant magnitude of the peak frequency on a power spectrum density. However, their method has no consideration of all the frequency contents of the discomfort, nor comparison between different peak frequency vibrations. Suzuki2 has emphasized that the vehicle vibration should be judged by a series of vibration stimuli to evaluate, because the vehicle vibration is time-variant, which isn’t a matter of the relationship between a single vibration stimulus and a subjective response. He clarified that the human sensation to the vehicle vibration discomfort changes every moment showing the relationship between the frequency-weighted r.m.s. acceleration calculated every 5 seconds and the category judgment to vehicle vibration discomfort every 5 seconds. However, his study doesn’t show what parameter connects to the subjective final judgment to vehicle vibration. Therefore, we applied the method similar to ISO100563 considering the time-variant to the vehicle seat z-axis vibration evaluation. The new method for the vehicle seat vibration considering the time-variant was examined on the hypothesis that the final subjective evaluation must be conducted from the judgment summarizing a series of vibration stimuli. Methods The vibration bench system, which reproduces the movement of a vehicle floor, was used for the experiment with the single-axis (vertical direction) four-post road simulator system, which is usually used for a car, as shown in Fig.1. The experiment was done on the right side of the vibration bench using the floor vibration which was 5.5 minutes, 0.822 m/sec2 (Wk) over the range 0.5-20Hz with 4 male subjects (age ave21.5, SD0.5, weight ave75kg, SD7.91kg, height ave166.8cm, SD5.2cm) and 4 suspension seats. As Fig.2 shows, subjects evaluated the degree of discomfort every 5 seconds to each seat vibration measuring the seat z-axis vibration acceleration. [ ]

Jan 6, 2006

By Daniel Connor, O&apos

The Cal-Sag Relief Sewer is a 2.6 m (8 ft 6 in.) diameter 9.1 km (5.7 mile) rock tunnel bored in dolomite for the Metropolitan Sanitary District of Greater Chicago. Included in the project are 18 shafts varying in depth free 70 m (230 ft) to 41 m (135 ft). This paper discusses how Healy/Vanessa reduced costs by eliminating conventional hand excavation by hoisting muck from a high production Robbins TBM (Tunnel Boring Machine) through small diameter drilled shafts and using a trailing rail-utility backup system.

Jan 1, 1985

By Debra F. Laefer

Jet grouting is a ground improvement technique that has become widely adopted over the past three decades, yet relatively little data has been published about performance characteristics of mixes under adverse conditions, such as the inclusion of clay lenses. This paper presents an experimental investigation on the impact of clay on the strength of jet grouting. A total of 150 grout samples were subjected to 0-10% levels of Kaolinite and Bentonite inclusion. While the Bentonite was introduced as a pre-hydrated slurry, the Kaolinite was mixed in two ways: in a pulverized condition and as large chunks. Sample strength and stiffness were measured at multiple dates within the first 28 days. With 10% clay inclusion all samples exhibited significant strength and stiffness losses. With some, substantial losses began with as little as 4% clay. Even a 1% clay inclusion tended to decrease strength and stiffness between one-quarter and one-third of the control sample. Depending upon clay type and inclusion method, results differed significantly with respect to strength and stiffness development and failure mechanism. Petrographic analysis is used to provide further insights as to apparently divergent behaviors.

Jan 1, 2009

By D. W. Olson

Estimated world production of natural and synthetic industrial diamond was about 630 million carats in 2004. Natural industrial diamond deposits have been found in more than 35 countries, and synthetic industrial diamond is produced in at least 10 countries. About 80 percent of the global output was produced in Ireland, Japan, Russia, South Africa and the United States. Russia and the United States are the world’s leading producers of synthetic industrial diamond. In 2004, the two U.S. synthetic producers, one in Pennsylvania and the other in Ohio, had an estimated output of 250million carats. Also in 2004, nine U.S. firms manufactured polycrystalline diamond (PCD) from synthetic diamond grit and powder.

Jan 1, 2005

By Wm. Terry Siemers, Frank E. Kottlowski, George S. Austin

The value of industrial rocks and minerals produced in New Mexico in 1978 exceeded $227 million. The state ranked first in the nation in production of potash and perlite and was a leader in pumice production. Other commodities with sizable production in New Mexico include barite, caliche, clay, dimension stone, fuorspar, gypsum, humate, limestone, mica, salt, sand and gravel, scoria, and silica sand. Non-metallic resources are distributed throughout the state, but development and exploitation is concentrated in western and southeastern New Mexico. The value of industrial rocks and minerals within the state grew about 9% to more than $227 million in 1978. Continued growth, however, depends on continued demand, exploration, and development.

Jan 1, 1982

By G Harbort, C Sola

The rapid development of geometallurgy in the mining industry has occurred in relatively recent times. Its importance as an independent discipline in the mineral processing world has been emphasised and recognised. To a large degree, this is the result of a growing understanding of the ore type being processed and their application to provide better metallurgical responses in different mineral processing techniques. The development has matured from early progress through to geological knowledge and into the realm of the metallurgist and mining engineer. Working together, they have developed a powerful framework that will interpret a body of mineralisation into measurable properties.The integration of geometallurgy and operations has become of increasingly important due to improvement in understanding of an orebody as a natural system formed by a number of processes and with a definite fabric of mineralisation within different geological domain. These have to be taken into account when creating techniques that will enable operations to extract the valuable components from a distinct type of ore. Incorporation of such knowledge at an early stage of development, such as the feasibility stage significantly reduces the project risk.This paper is written from the unique perspective of a process engineer embedded within a geological team. It discusses issues such cross discipline communications and misconceptions and details the numerous tricks, traps and treasures of geometallurgy encountered during defining of the Seminco and Taysan resources.CITATION:Sola, C and Harbort, G, 2012. Geometallurgy - Tricks, traps and treasures, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 187-196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By L. Raaths

This paper outlines the process of improvement utilizing performance monitors and GPS systems on an opencast strip mine. Its primary focus is to maximize coal exposure by draglines and secondly to improve on those processes impacting directly on the dragline operation. The Aquila (DM2/5 system) navigation and monitoring systems were installed on the overburden drills. Their main function is to eliminate manual staking and positioning thereby ensuring a regular pattern being drilled. Holes drilled to planned depth reduce drill metres and it minimizes coal losses and contamination at the coal interfaces. The CAES (Computer Aided Electronic System) will be installed and evaluated on the Caterpillar D11 dozers at Optimum. This system ensures a correct dragline pad elevation through the use of planned elevations and GPS technology to achieve the optimal pad elevations for draglines consistently. The draglines are equipped with a Dragline & Operators Performance Monitor. This monitor allows the operator to control his own performance. It reports on all productivity, method and poor operating techniques. These monitoring systems send critical operational information back to the office. This source data resides in central databases from where it is converted and integrated into management information. To manage an operation means that you as a manager must be able to set objectives and targets and to achieve your goals the activities involved must be measurable.

Sep 1, 2001

By R. G. Fleck, W. R. Webb

The concentrate produced from the Adirondack magnetites is, of course, too fine for direct use in a blast furnace and must be agglomerated before it can be considered a blast furnace ore. The four operations in the area use sintering -three, including the Jones & Laughlin operation, employing the Dwight Lloyd continuous type machine and one operation using the Greenawalt batch type process. Each operation uses fine anthracite coal, either No. 4 or No. 5 buckwheat size, for the mix fuel.

Jan 6, 1950