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By David L. Bradfield

This paper covers the development of the Yeelirrie Uranium Project from the discovery of the Yeelirrie deposit in 1970 to the present time, with emphasis on the mining, processing, and environmental requirements of the project. The Yeelirrie Uranium Project is managed by the "Yeelirrie Uranium Joint Venture Partnership", which, when formed, consisted of Yeelirrie Development Company Pty., Ltd., Urangesellschaft, Australia Pty. Ltd. and Esso Exploration and Production Australia Inc. The Yeelirrie Uranium Joint Venture Partnership holds mineral claims over the Yeelirrie uranium ore deposit in Western Australia. This deposit encompasses some 35 million tonnes of ore containing in excess of 50,000 tonnes of uranium as U308. Agreement has been reached with the State of Western Australia to mine and process the ore to produce uranium ore concentrate. The Project scope provides for an open-cut mine, alkaline leach hydrometallurgy plant, power plant, township, airstrip, access roads, community services and utilities. The Yeelirrie Uranium Project described herein has progressed through the stages of exploration, mine evaluation, process testing, project scope definition, environmental approval, Pilot Plant operation, preliminary engineering and the publishing of a definitive Project Feasibility Study. This article summarizes the project development through the above stages.

Jan 1, 1984

By J. Sharp, R. Arnold, P. Rusin, T. Young, N. A. Sinclair

Many oxide silver and molybdenum deposits remain undeveloped because chemical extraction yields poor recoveries or is environmentally unacceptable. Bioreductive leaching of such ore samples at MBX resulted in high extractions of silver and molybdenum. When baseline, three-day, cyanide bottle-roll tests were conducted on manganiferous-oxide silver ore, 13.7% of the silver was extracted. In contrast, 86% of the silver was microbially solubilized into the organic growth medium by bioreduction with 99.8% dissolution of manganese. A followup cyanide bottle-roll test yielded an additional 8.5 % silver dissolution, for a total extraction of 94.5%. Baseline, three-day, acid bottle-roll tests of the iron-oxide molybdenum ore Yielded 1.8% molybdenum. However, bioreduction solubilized 93.3% of the molybdenum into the growth medium. An additional 0.3% molybdenum was solubilized during the followup acid bottle-roll test. Microbial treatment of refractory oxide ores with bioreductive bacteria resulted in higher extractions of silver and molybdenum than conventional chemical leaching. The bioleaching process occurred at a near-neutral pH at ambient temperatures. The bacterial solubilization of silver and molybdenum was achieved without the use of cyanide or sulfuric acid.

Jan 1, 1993

By Randal J. Barnes

The nonlinear network optimization algorithm developed in this paper solves the following mine ventilation design problem: find the location and size of all fans and regulators which minimize the overall system power consumption while satisfying all physical, legal, and operational constraints. This work includes the formulation of the problem within the framework of mathematical optimization, the development of the computational theory, and the creation of an efficient solution methodology. The algorithm has been implemented on a microcomputer, and a small but representative example is included. The algorithm presented in this paper has four limitations. First, the optimization process is for a single point in time: the dynamic nature of a mine ventilation system in an evolving mine is not directly addressed. Second, the topology of the ventilation network is required input information. The mathematical algorithm does not optimize the size or location of the mine ventilation airways; however, the post optimality analysis techniques can be used to aid in topological decisions. Third, the problem is formulated using volumetric flow; thus, heat and moisture transfer are ignored. Fourth, the capital cost of ventilation equipment is not included in the formulation.

Jan 1, 1989

By S. A. F. Murrell, M. Hong, L. J. Bond

This paper investigates the propagation, interaction and scattering of explosively generated seismic waves with discontinuities in rock masses using numerical models which employ a finite difference method. The models consider 2-D systems and give a full solution including mode-conversion in the mid-frequency scattering region where feature dimensions are of the order of the wavelengths involved. The paper has two parts, the first of which considers wave propagation and diffraction by simulating an explosive body source in a half- space containing a step or a slot on the surface which represent a cliff and a rift valley that has dimensions of the order of the wavelengths in the source. The second part of the paper reports a hybrid technique which combines a perturbation method and the finite difference method for wave propagation again caused by an explosive body source in a 2-D half-space system but with a shallow surface obstacle, such as a smooth ridge, with elastic constants slightly different from bulk material and the slope of this surface topography are shallow. This hybrid technique is also reported being applied to a half-space with a horizontal void or insert.

Jan 1, 1986

By C. B. Manula

The total systems model for underground coal mine planning and design (Master Design Simulator) is a set of computer programs which encompasses a realistic reproduction of the interaction among the geological, environmental, equipment, methods, and the health and safety aspects of the mining plan (Manula, Rivell, and Ramani, 1975). The total system includes nine major subsystems: geology and reserves, methane generator, roof support, subsidence, production, rail haulage, cost, water generator, and ventilation (Fig. 1). The subsystems themselves are divided into two categories based on the frequency with which they are executed: (1) event-oriented subsystems are executed either independently or at discrete intervals when certain specific events occur; and (2) dynamic subsystems function interactively during the production cycle, transferring data to or requesting data from event-oriented subsystems only when specific events occur (Fig. 2). Each subsystem has been tested and validated independently (Ramani, White, and Sutton, 1974; Ramani and Owili-Eger, 1974; Manula, Mozumdar, and Jeng, 1974a; Manula, Mozumdar, and Jeng, 1974b; Manula, et al., 1974; Manula, Rivell, and Sanford, 1974; Ramani, McClay, and Burgos, 1975; Manula and Owili-Eger, 1975; and Ramani, Owili-Eger, and Manula, 1975).

Jan 1, 1979

By Robert J. Timko, R. Lincoln Derick

The Bureau of Mines evaluated the integrity of escapeways in a three entry underground coal mine. A center conveyor belt entry (secondary escapeway), was flanked by an intake (primary escapeway) and a return entry. Diesel equipment was used throughout the mine for material and personnel haulage. A carbon monoxide monitoring system, tied to a data recording computer on the surface, was deployed throughout the belt entry and at selected sites in the intake and return entries. Previously, the company had a fire of unknown origin in another mine, which prompted an interest in the performance of their escapeways. An initial, qua1itative evaluation was performed by burning approximately 14 kg of coal at the mouth of the intake entry. The first test was followed by a similar burn at the mouth of the belt entry. These initial trials showed a high quantity of leakage between entries. In several follow-up evaluations, simulated fires, using a tracer gas, were set in the intake and belt entries. Tracer gas concentrations were obtained in all entries at four different underground locations. The results of these tests showed that permanent stoppings could not guarantee isolated, contaminant-free escapeways.

Jan 1, 1989

By Morgan M. Sears

In recent years, one large mine collapse and numerous smaller bump events have resulted in a renewed interest in coal bump research. With numerical modeling, the Energy Release Rate (ERR) calculation quantifies the ?release? of the gravitational potential energy of the rock mass into the environment as mining progresses. This release of energy can occur passively in the form of heat and sound or dynamically in the form of pillar bumps or rock bursts. From the initial application of a calculated energy release rate in the deep hard-rock mines of South Africa, the ERR was found to have a significant correlation with the risk or potential of damaging coal bumps or rock bursts. In this research, an ERR calculation is incorporated into the modern LaModel program to facilitate the analysis for potential coal bumps. Initially the ERR calculations in LaModel are verified using a case study of cut sequences originally modeled using the MULSIM/NL program. Then, the ERR calculations are applied to a bump-prone mine in Southern Appalachia were a number of different pillar recovery cut sequences were used in order to minimize the risk of bumps.

Jan 1, 2009

By J. H. Tylczak, R. Blickensderfer

Impact and abrasion properties of various commercial US grinding halls were evaluated and compared by the Bureau of Mines, US Department of the Interior. Laboratory tests were conducted on balls obtained from eight major US manufacturers. The halls included forged steel, cast steel, and alloyed white cast iron and were subjected to repeated impacts until they broke or until 300,000 impacts were exceeded. Pin abrasion tests also were conducted. The results showed wide differences in impact lives, ranging from a few thousand to over 500,000 impacts. The life of inferior commercial halls was increased five to six times by a laboratory tempering heat treatment. For halls that did not break, the major impact wear mode was spalling and ranged from an average rate of 0.28 to 4.46 mg per impact. The softest halls (steel) had excellent impact resistance but low abrasion resistance. The abrasion resistance of the steel halls generally increased with hardness. The alloyed white cast irons had about twice the abrasion resistance of the steel halls. Users should become aware of the wide variations among commercial halls, and ball manufacturers should be aware that their product can he improved.

Jan 1, 1990

By Otis M. Clarke

Observations of the land surface show that subsidence over active and abandoned underground mines is controlled to some extent by the stratigraphic and structural geology of the mines in addition to the methods of mining and the thickness of the seam mined. Exposures in highwalls of surface mines that intersect abandoned underground mines in the Warrior coal basin of Alabama illustrate this, showing sandstone beds that act as beams bridging openings and interbedded shale beds crumbling. Stratigraphic changes observed in the district are extremely variable and calculations regarding subsidence used for one area will not apply to another area if there is a major change in rock types Rocks exposed in road cuts and open pit mines demonstrate a marked difference in weathering characteristics. Some rocks, such as shale, wea- ther very rapidly, by crumbling and becoming plastic, whereas other rocks, such as sandstone, resist weathering. The continuing rock weathering after mining in openings produced by the mining activity and in fractures caused by roof movement, apparently, is a major cause of the surface sub- sidence that may occur years after the mines are abandoned.

Jan 1, 1986

By Joseph S. Malesky

The discovery and development of explosives mark one of the most important findings in the history of civilization. Without explosives our vast economic enterprise concerning the mining of coal, copper, iron, aluminum, and various other ores could not function. Explosives are used in all kinds of construction works, in the razing of old buildings, blasting of trenches, driving of tunnels, and in many other instances common to our everyday life. For these reasons explosives are rightfully referred to as the forerunner of progress. An explosive may be defined as a substance (usually a mixture) that, when flame or shock is applied, yields readily to rapid combustion or oxidation, accompanied by the formation of such relatively large quantities of gases as to produce much violence and pressure which, in turn, react against their surroundings and cause what is termed an explosion. By their very nature the action of explosives is destructive and disruptive of adjacent materials. Decomposition of explosives can occur through deflagration, which is rapid burning or combustion, as in the case of black powder, or through detonation, which is an almost instantaneous disruption, as in the case of dynamites and blasting agents.

Jan 1, 1981

The following list is a representative sample of the types of software available to the mining industry. For additional information concerning software packages for your minicomputer, contact equipment manufacturers or software suppliers.

Jan 11, 1981

By Donald H. Sargent

This paper focuses upon the changing character of the market for Western bentonite, and upon transportation methods and costs affecting this market. The basis for the data in this paper, in addition to public sources of information such as federal and state government agencies and the open literature, was a program of 57 face-to-face interviews with individuals knowledgeable in the bentonite production, consumption, and transportation industries. The study was performed in 1974 and 1975 by Versar Inc., for the Bureau of Land Management, Department of the interior.*

Jan 1, 1979

By Jean Paul Duterque, Morris J. V. Beattie

In many parts of the world, pyrite and arsenopyrite occur together in sulphide ores either as the only sulphide minerals or in conjunction with other valuable sulphides. It is desirable to produce separate concentrates of the various sulphide minerals, including pyrite and arsenopyrite, so that the contained desirable metals can be recovered economically. It is common, for instance, for gold in an ore containing both pyrite and arsenopyrite to be associated almost exclusively with the arsenopyrite. It is desirable in this instance to produce an arsenopyrite concentrate for gold recovery while rejecting the barren pyrite.

Jan 1, 1992

By Thor Skjeggedal

The Norwegian contracting firm A/S Høyer-Ellefsen has for the last 2.5 years carried out substantial pregrouting in a 7600m long tunnel just outside the city of Oslo. This has been done to avoid groundwater lowering and consequent damage to surface structures. A WIRTH TBM is used in combination with a 2 boom Atlas Copco hydraulic jumbo for the drilling of groutholes in front of the machine. The detailed procedure for the drilling and grouting will be discussed, and the results obtained will be presented.

Jan 1, 1981

By Fathi Habashi

CLAYS CONTAIN the mineral kaolinite, a hydrated aluminum silicate. It is an important potential raw material for aluminum, especially for those countries possessing no bauxite deposits. Therefore, there is no surprise to find a large volume of research done for the recovery of aluminum from clays. Kaolinite (Al203?2 SiO2?H20) contains 39.8% A1203; 46.3 % SiO2, and 12.9 % H2O. The analysis of a good-quality dried clay of an Eastern Canadian siliceous shale is shown in Table 8-1.

Jan 1, 1970

By M. E. Gershon

An approach for scheduling the mining of ore and waste blocks in a surface mine is presented. While mathematical programming approaches have been developed to solve this problem optimally, they are difficult to implement and understand. The more simplistic approach presented here achieves practical mining schedules, taking into account both long- and short-term considerations. The key to the approach is use of the concept of ranked positional grade. The program can determine a complete schedule for a specified time period, or it can be used interactively as a guiding tool for the engineer.

Jan 1, 1988

By S. B. Bhagwat

Before the Clean Air Act Amendments of 1990, coal policies-especially coal research policies-were geared to find a solution to the sulfur emission problem. However, technologies to reduce sulfur emissions cannot be tailored for a single coal. A technology that will clean Illinois coal to compliance levels will do the same, or nearly the same, for most other types of coal. This paper will discuss an integrated approach to the analysis of the future of coals from different regions in the United States and its implications for coal-related policies by government and industry.

Jan 1, 1994

By Paul D. Chamberlin

The evolution of heap and dump leaching has followed the development of agglomeration, materials of construction for leach pads and ponds, solution distribution systems, testing techniques, and state regulations. They are now mature processes. Possible future directions and developments are discussed. In situ leaching of precious metals is waiting to be commercialized. Regulators are reluctant to allow the use of cyanide because of the potential for excursions and operators are reluctant because of the potential for lawsuits. Developments in alternative lixiviants are needed before in situ leaching is accepted.

Jan 1, 1989

By Robert F. Conley

This paper describes attrition milling as exemplified in rotary and vibratory mills for ultrafine grin¬ding application Without attempting to narrate the differences between various devices, generalized differences between the broad categories of rotary and vibratory milling are presented and compared with the ball mill Applications of these mills for coal, limestone, kaolin, mica, talc and iron oxides are described giving specific differences of the mineral properties that affect their behavior in the grinding mills Where applicable, specific recommendations are provided for ultrafine grinding of various industrial minerals

Jan 1, 1983

By L. Sletmoen, P. Rocque, E. DeSouza

Plans for achieving planned production rates at the Red Lake Mine High Grade Ore Zone required that the mine ventilation system be upgraded. Time constraints required that only a site assessment of the mine ventilation system be performed followed by recommendations for providing adequate ventilation conditions at the production zone. This paper describes the engineering assessment, design and commissioning of the ventilation system upgrade for achieving increased flows at the high grade ore zone. The work was successfully achieved with minimal capital expenditures and disruption to the mining cycle.

Jan 1, 2003