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Results of the study of chloride ion concentration effect to osmium-187 sorption from wastewater of copper smelter with use of foreign anionites of different basicity and structure are presented in the work. It was found that the increase of chloride ion concentration in the wastewater helps to increase recovery of osmium using anionites regardless of their nature. The ways to intensify the process are proposed. The method for osmium elution from the anionites with potassium iodate solution was developed. It was shown that the method lets to recover up to 99% of osmium from the anionites. Recommendations for selection of eluents for better recovery of osmium from the anionites were elaborated. Keywords: wastewater, osmium, anionite, sorption, chloride ions, eluent, recovery

Sep 1, 2012

By Secis R

Northparkes Mines is located 27 km northwest of Parkes in central west New South Wales. The E26 deposit is the largest of all defined to-date in the area, containing over 50 per cent of Northparkes' resources and reserves. The combination of orebody geometry and geotechnical characteristics provide ideal conditions for the block cave method of mining of the first lift of the E26 deposit. Although this method of underground mining has been used for decades in other countries, E26 is the first example of its use in Australia. Copper-gold mineralisation at Northparkes is related to quartz monzonite porphyries that have intruded coeval Ordovician volcanics. Sulphide mineralisation (dominantly bornite and chalcopyrite) occurs principally within quartz veins associated with the porphyry intrusions. Veining and mineralisation occurs within both the porphyries and volcanics. To optimise the recovery of a resource within a block cave mine, a good understanding of the rock mass and ore flow characteristics is essential. These have a significant effect on the fragmentation size and range and on parameters such as the drawzone spacing, height of interaction zone and dilution entry. As ore within a cave column moves and mixes when material is extracted from below and beside it, the total reserve extracted is unique for a particular draw strategy/production history. Until recently, reserve estimates and production schedules were based on the application of a uniform dilution factor to the tabulated resource. However, given the complicated flow and mixing within the cave column, such a simplistic approach can produce erroneous results. Northparkes Mines purchased and sponsored the upgrading of a commercially available software package specifically developed for modelling removal of resource blocks under caving conditions. This Gemcom software package, PC-BC, has been used for mine planning, reserve reporting and production scheduling. Blocks within it resource block model are converted into a mineable reserve taking into account mixing and dilution during depletion of drawcolumns (by horizontal and vertical redistribution of insitu tonnage and metal). As PC-BC gives individual drawpoint reserves, it can be used during the planning stage to determine whether or not a drawpoint is economic. For E26 Lift I an optimal layout containing 130 drawpoints has been developed based on a nominal 14 m x 14 m drawpoint spacing and a 0.8 per cent equivalent copper (eCu) cut-off grade. Annual production schedules for the depletion of material above this layout are based on: I higher tonnage removal from higher grade drawpoints in the early years of production; and 2 drawpoint production rates proportional to the total tonnage of orr remaining in the drawcolumn up to the optimal height of draw tier subsequent years. The reserve is tabulated from the combined annual production schedules over the life of the lift. The pre-mining reserve for Lift I of E26 is 26.6 Mt at 1.43 per cent copper and 0.39 g/t gold, of which approximately 23.4 Mt will be extracted under caving conditions. By scaling down the annual production schedule, weekly drawpoint tonnage calls can be given for short-tern production scheduling.

Jan 1, 1997

By Terry Matts, Henry Heidrich, Cluny Randell, Carl Kottmeier

Until 1990, all production of asbestos ore at Cassiar was by open-pit methods. With the impending exhaustion of open-pit reserves, a decision was made in February 1988 to continue mining underground, using the block-caving technique.

Jan 1, 1992

By Carl Sunderman, Steve Signer

Researchers at the National Institute for Occupational Safety and Health (NIOSH) have developed several new tools for evaluating roof support performance. A miniature data acquisition system (MIDAS) was developed that can collect readings from up to 16 strain gauges at regular time intervals and store the readings for later retrieval. Three LED lights change from green to yellow, then red, based on the reading levels and/or rates of change of rock movement. This feature can be used to warn miners of rock instabilities. The system can be used with any strain-gauged support (resin bolt, friction bolt, cable bolt) or with a newly developed rock strain strip (ROSS) developed by NIOSH to measure rock strain. A ROSS is grouted in a hole drilled adjacent to the rock support to be evaluated; the deformed shape of the ROSS provides anchorage on either side of the strain gauges. Data from both laboratory tests and field evaluations are presented that describe the capabilities of both the MIDAS and ROSS instruments.

By L. S. Richardson, N. J. Grant

Iodide-grade titanium, two oxygen alloys, and two aluminum alloys were studied by means of creep-rupture tests from 1000° to 2000°F. From the test information an evaluation was made of, 1) the relative creep-rupture strengths of the u (hexagonal-close-packed) and 0 (body-centered-cubic) forms of titanium and some of its alloys; 2) the effects of solid-solution strengthening by oxygen and aluminum on the u and 0 structures; and 3) the extent and effect of atmospheric oxygen alloying on rupture life in tests above about 1000°F. THE use of titanium alloys at temperatures above 1000° F has been considered unlikely by most investigators because of low creep strength (based on a requirement for room-temperature ductility, formability, and weldability) and low oxidation resistance. The results of this testing program do not entirely uphold this pessimism in terms of strength and oxidation resistance. The observations described below are based entirely on stress-rupture results, although some creep tests were also carried out on these alloys. Three items of primary importance are covered: 1) Stress-rupture data in the form of the Larson-Miller parameter curves for several titanium alloys at temperatures up to 2000°F; 2) The relative strengths of the hexagonal-close-packed a structure and the body-centered-cubic 0 structure; 3) The effects of solid-solution alloying on the creep-rupture properties of titaniu'm at elevated temperatures. Only two investigatons have reported the creep- rupture properties of titanium at temperatures above 1000° F. Lunsford and rant' tested iodide titanium; their values are also utilized in the paper. EXPERIMENTAL PROCEDURE After a few tests had been made in a conventional creep-rupture test machine, it became clear that some sort of atmospheric protection would be necessary for short-time tests conducted at temperatures above 1600°F, or for times greater than 100 hr at 1200°F or above. Several furnace units and test machines were constructed, the most successful of which is shown in Fig. 1. Certain experimental difficulties peculiar to titanium were encountered; for example, the use of molybdenum holders was dictated because titanium forms low melting-point eutectics with conventional high-temperature alloys containing appreciable amounts of iron, nickel, or cobalt. This same difficulty made the use of chrome l-alumel thermocouples in direct contact with a test specimen impossible, above about 1500" F. The high-temperature high-vacuum furnace shown in Fig. 1 was capable of maintaining a vacuum of better than 10"5 mm of mercury at 2000°F (pressure measured in cold part of system) and 5 X lo-' mm at room temperature. Most of the tests eonducted in vacuum were at temperatures

Jan 1, 1960

The Mineral Research Centre is located at Perth in the suburb of Waterford, adjacent to Curtin University of Technology and within a Technology Precinct which includes Technology Park. The Centre, constructed by the WA Government at a cost of $16 million and occupied in late-1994, comprises three separate buildings housing the CSIRO Division of Minerals, Curtin University's School of Chemical Engineering and the Mineral Processing Laboratory of the Department of Minerals and Energy. The emphasis on R&D at the Centre is primarily in hydrometallurgy as a result of staff expertise, extensive bench and pilot-scale facilities, track record with the industry and, very importantly, two of the occupiers being partners in the AJ Parker Cooperative Research Centre for Hydrometallurgy. Staff in the Centre have a long involvement with R&D agencies such as AMIRA and MERIWA. The hydrometallurgical focus of the Centre complements that of pyrometallurgy at the GK Williams CRC in Melbourne and the Centre for Mining Technology and Equipment in Brisbane, to ensure that the mineral processing industry in Australia has access to a complete range of expertise and facilities to serve its needs.

Jan 1, 1996

By D. W. Hill

By seeking to define the social and political parameters of both established and potential uses of the underground, this paper will attempt to formulate and state the problem posed in the realms of public choice for obtaining more rapid development and more beneficial use of the underground environments. Essentially, the paper will pursue the following outline: 1. Established policies and established uses of the underground 2. Potential uses of the underground for social benefit 3. Constraints on development and policy a. Psychological constraints b. R & D plus physical constraints c. Economic constraints d. Public choice and policy contraints (both governmental and non-governmental) e. Legal and other structural constraints 4. Defining the problem from the social standpoint 5. Suggestions for surmounting the constraints and meeting the problem: some hypotheses for the future.

Jan 1, 1974

By R. B. Mears, E. H. Dix, R. H. Brown

In the Institute of Metals Division Lecture of 1940, E. H. Dix, J~.(I)~ discussed the acceleration of the rate of corrosion by high constant stresses. Experimental data obtained on this subject at the Aluminum Research Laboratories and a theory compatible with these facts were included in that lecture. The present paper contains data and ideas subsequently developed at the Aluminum Research Laboratories. Dix pointed out that in order for acceleration of corrosion by constant stress to occur: (1) There must exist in the alloy a susceptibility to selective corrosion along more or less continuous paths, as for in- stance at grain boundaries, and (2) There must exist a condition of high stress acting in a direction tending to pull the metal apart along these continuous paths. Acceleration of corrosion rate by stress is not confined to any one alloy system. Table I lists some of the metals and alloys and some of the corroding environments in which acceleration of corrosion by stress was sufficient to cause cracking (stress- corrosion cracking). It will be noted that the variety of alloys in which stress-corrosion cracking has occurred is rather large. Also, it will be observed that

Jan 1, 1945

To design an apparatus that advances the state of the art in gas content testing equipment. The goal of the design is to incorporate improvements in testing sensitivity/accuracy, durability, and ease of operation over existing equipment. It is also desirable for the new design to successfully perform gas content determinations of multiple chemical species from a rock sample.

Jan 1, 1999

By Alvinus Brown Wood

The ancient copper-mines of Lake Superior, having been destroyed or covered by modern mining-dumps, are not accessible to the present inhabitants of that region, and, since no more are likely to be found, some account of those already discovered, from one who has seen them, may be acceptable to the Institute. Early in May, 1855, I took a party of men to open an ancient pit on the Quincy mine-location. Mr. C. C. Douglas was the " Agent," as mine-managers were then called on Lake Superior. The Quincy Co. had previously done work on a fissure-vein, several hundred feet west of the Amygdaloid lode (afterwards called the Pewabic lode), on which was the ancient pit herein described. 'It was at this pit that the Quincy main shaft was subsequently sunk. The ancient pit showed an apparent depth of about 4 R., but when cleaned out it was shown to he 14 ft. deep, having been filled up by the sliding-in of material composed largely of broken rock, taken out in sinking the ancient shaft, and left near its mouth. Midway of the shaft, and below water-level, was found a scaffolding of white-birch poles, which had been used as a landing, to assist in removing the excavated rock. The shaft was 7 ft. in diameter. The excavation had been done by first building fires in order to disintegrate the rock, as was proved by the abundance of charcoal found; then breaking the softencd rock with hammers of diorite, such as is found in the greenstone range on Keweenaw point. These hammers had about the size of large paving-stones. Only broken ones were found, the whole ones having been doubtless carried away for other work, such as could be traced on the lode for a hundred feet or more to the south. At the place where this shaft was sunk, barrel-copper (i.e.,

Jan 1, 1907

By G. Caron, M. Boisclair

In 2005, CANMET-MMSL used its pool of expertise in ground control, open pit and underground mine engineering, mineral processing, information technology and applied mineralogy to launch a mine-to-mill research project. The objective of the project was to optimize the distribution of rock breakage energy among blasting, crushing and grinding activities, thereby maximizing the efficiency of energy utilization within comminution processes. Tests were designed to demonstrate that this approach could reduce the energy consumption, thus contributing to the reduction of Green House Gas (GHG) production in the Canadian mining industry. The project was accomplished in collaboration with DynoConsult and Dyno Nobel Canada Inc., a world leader in commercial explosives. Data analysis from 12 blasts (six with electronic and six with pyrotechnic detonators) in three different geological formations of a quarry (soft, medium and hard rock) shows that electronic blasting technology increases rock fragmentation by 15% (in hard rock) to 20% (in soft rock). A more uniform rock fragment size distribution is also obtained. The impact of the improved quality blast product on downstream processes of the quarry is a productivity increase of 5% in rock excavation and transportation, an energy reduction of 10% at the primary crusher and an increase of 15% of the primary crusher throughput. A soft-sensor prototype, based on primary crusher data (i.e. energy consumption, throughput, feed and product size distribution) and a simplified computerized process model, was developed for on-line measurement of the rock operating work index. Additionally, 385 rock samples and specimens were collected and prepared to determine the tensile and compressive strength of the rock material, to evaluate the aggregate crushing work index, and to examine the development of micro- and macro-fractures by means of binocular and SEM microscopy. Blast-induced rock damage was evaluated at the end of the laboratory testing program. Even though a reduction of rock hardness of around 30% was observed after blasting, the impact of the blasting method (i.e. use of electronic or pyrotechnic detonators) on the induced rock damage could not be observed. It is either absent or not perceptible with the accuracy of the measuring techniques and the number of samples analyzed.

Jan 1, 2007

By John V. Beall

Spots Goblenski fluffed up his pork chop sideburns, checked the angle of his wide brim Stetson and ambled off the airplane. The pert Braniff hostess stood smartly at the door. "Goodbye now, take care," she said in the special airline stewardess voice superimposed on a Texas drawl. Spots smirked, "You betcha, Peaches, you too." It was a crystal clear, sunny day which New York can have at any season of the year (but rarely gets credit for) and being in high spirits Spots did not mind being captured by a cab driver. That is the cab driver brushed aside all other conversation to give a continuous colorful commentary on New York politics, revealing in the process that only the very wealthy and cab drivers share the same political views in that city. After installing himself in the fading opulence of the Hotel Roosevelt, he finished the day with a steak dinner with baked potato under sour cream and hearts of lettuce salad with Roquefort dressing at the Black Angus restaurant. The next morning he had an appointment with Hemphill, Frye and Louderdock. The offices of this prestigious firm of management consultants are high in the Pan Am Building. He was courteously received by a lacquered receptionist and was soon escorted into the presence of Mr. John Smith. "Ah, Mr. Goblenski; Spots, isn't it? Hope you had a good flight. Lovely weather we are having. Just make yourself comfortable over there, Spots." Smith seemed cordial and Spots slipped comfortably into the interview. He had always thought that management consultants were evolved from the "efficiency experts" made famous by the radio team, Amos and Andy. He associated the modern version with computers, PERT and other systems approaches. He was surprised that one of these firms was apparently acting as an employment agency. "Of course" continued Smith, "in evaluation of basic criteria of performance moduli, the human element enters, Spots, and that brings us to you." Spots sat up and focused his attention.

Jan 1, 1970

By F. F. Peng, D. C. Yang, G. Yanief, E. H. Cho

This study deals with carrier flotation of cerium dioxide, a surrogate of plutonium oxide, which is the major contaminant at the Nevada Test Site (NTS). The objective of this study was to determine the feasibility of using carrier flotation for remediation of the site. In this study, a - 200-mesh fraction of pure cerium dioxide was used. Oleic acid was used as the collector, while calcium carbonate was used as the carrier. Mechanical-cell tests were conducted to float the surrogate from a mixture containing uncontaminated NTS soil, both in the absence and presence of the carrier. It was found that the addition of the carrier drastically enhanced the flotation recovery of cerium dioxide. The flotation recovery of the surrogate increased from 34% to 65% by adding only 0.5% calcium carbonate (-150 mesh). The recovery further increased to 95% by adding 10% calcium carbonate. The flotation method utilizing a carrier of calcium carbonate seems to have a high potential for the remediation of the soil contaminated with radionuclides at the NTS.

Jan 1, 1998

By S. Dubnewych, S. Kieffer, M. T. McRae, R. R. Redd

The seismic vulnerability of the existing outlet tower at Lake Mathews reservoir, located in Riverside County, California, necessitated the design of a new outlet facility to assure serviceability of the facility following a major earthquake. The components of the proposed facility include: a new outlet tower; a shaft; a new outlet tunnel; an approach channel that will be excavated underwater; and two short tunnels that will connect the new outlet tunnel to the existing outlet tunnel via the shaft. As the new facilities will be constructed while the reservoir is in operation, a cofferdam will be constructed around the site of the new outlet tower. The design for the underground facilities used a combination of empirical methods; limit equilibrium analyses, including displacement-based pseudo-static analyses for dynamic loading conditions; and numerical analyses. This paper outlines the design methodology used to develop an innovative design for the facilities which can be constructed within the time frame required by the operational schedule of the reservoir and existing outlet facility.

Jan 1, 1999

By H. L. Monro

The individual supplies of and demands for gold that make up the total supply/demand structure in any year, together with their individual price elasticities, are used to determine the effect of forward sales on the gold price.

Jan 1, 1992

By R. F. McFarlin, H. E. El-Shall

Since its inception, the Institute of Phosphate Research has examined every promising proposal in order to find an economical, practical and environmentally sound method of dewatering phosphatic clays. The in-house development of the FIPR/DIPR process (DIPR = Dewatering Instantaneously with Pulp Recycle) would appear to answer that quest. When small amounts of fibrous materials are mixed with clay slurries and flocculent, rapid dewatering occurs. Clay solids contents of 20 to 25% can be attained by simply rolling the clay mass down an inclined screen. Higher solids (>40%) are reached by physically pressing the cake; e.g., with a belt press. Because mechanical pressing devices are too expensive for phosphatic clay treatment, FIPR has developed the "sandwich" method of simultaneously dewatering the phosphatic clays and reclaiming the mine cut, as well as a second alternate, the "median strip" proposal. Economic projections of these bench-scale alternates suggest that the FIPR/DIPR process should be no more costly than present practice, when credit is given for the simultaneous reclamation accomplished.

Jan 1, 1993

By Serge Borel

An efficient design method is proposed for "piled-footing" and "piled-raft" foundation under lateral loads. It combines the methods used for the displacement design of shallow and deep foundations and takes into account the interactions between the piles and the cap or raft. This method has been applied to previous full-scale tests carried out in the United States. Two groups of six instrumented driven piles were laterally loaded several times: first with the concrete pile cap in direct contact with the soil, and then, after a thin layer of soil had been removed beneath the cap. The proposed method models well the real behavior of piled-raft foundations. It highlights the positive effect of the cap in contact with the soil, which reduces significantly the displacements and the maximum pile bending moments. These are divided by two for the analyzed case histories.

Jan 1, 2002

By Spencee L. Willett

In 1986, at the request of the Bureau of Land Management, the U.S. Bureau of Mines studied a 51, 160-acre portion of the 107,920-acre Diablo Mountain Wilderness Study Area (OR-001-058) in order to evaluate its mineral resources. The study area is located 1n Lake County, OR, about 45 miles northwest from Lakeview. The study area is located near the northwest corner of the Basin and Range physiographic province. Tertiary Picture Rock basalt with tuff interbeds underlies the area (Travis, 1983). No mineral resources were identified; no mines, prospects, claims, or mineralized areas exist in or adjacent to the Diablo Mountain study area.

Jan 1, 1987

By Peter Zhang

Shield recovery in a longwall move is normally conducted from tailgate to headgate. However, if the face is wide and the immediate roof is weak, difficult conditions with considerable roof sag, excessive shield load, and local roof falls could occur as the shield recovery proceeds to the middle of the face, causing delays in shield recovery. The situation could be aggravated when a pre-driven longwall recovery room is employed. Alternatively, a bi-directional approach for shield recovery, i.e. shield recovery starting from the middle of the face towards both tailgate and headgate, can alleviate the roof sag significantly by quickly withdrawing the shields towards the lower abutment pressure zones at the headgate and tailgate sides. In this case, the bi-directional shield recovery approach was used in a longwall move for a 1450 ft wide face under weak roof conditions. Shields were successfully withdrawn within five days without experiencing significant roof sag. The time-dependent roof-to-floor convergence, shield pressure, and roof conditions were monitored during shield recovery. 3-D finite element modeling was conducted prior to longwall move to evaluate the difference between a uni-directional and a bi-directional shield recovery during a longwall face move. Vertical stress, yield zone in and around the recovery room, load on the shields, and convergence at the center of the shield canopy were obtained from computer modeling, and compared with the data from field monitoring. Finally, the advantages of the bi-directional shield recovery are discussed.

Jan 1, 2007

By M. R. Henzinger, W. Schubert

"The quality of the backfill applied at a shield driven tunnel is of significant importance failure of the lining. The used material also affects the interplay between support and excavation behaviour.In this research the state of the actual bedding situation is investigated by an analytical approach, laboratory tests and numerical simulations. The numerical simulation using continuum methods have shown shortcomings. These shortcomings regarding the instability of large strain simulations restrict the possibility to reproduce the relocation of the backfilling material. The performed scaled model tests have shown that the regripping process of a double shielded tunnel boring machine affects the soil failure within the gap. With the analytical results the influence of the wall friction can be predicted. Therefore the angle of the failure surface can be determined. The results have shown that the wall friction significantly increases the failure angle. INTRODUCTIONFor tunnel boring machines (TBM) with single (SM) or double (DSM) shield, precast liningsegments are used as rock support. These segmental linings are installed within the protection of the TBM shield. In order to reduce the friction while advancing, the shield diameter is smaller than the diameter of the cutter head and therefore also smaller than the excavation boundary. The difference depends on the expected radial convergences. Since the lining segments are mounted within the shield the steering gap between the shield and the excavation boundary increases and is hereinafter called annular gap.In the process of tunneling in hard rock, the annular gap is usually filled with fine grained and closely graded gravel, termed as pea gravel. The backfilling process starts as soon as possible after the shield tail passes the lining. Due to the operational procedure within the working area of a TBM, a fully backfilled annular gap might not be established after every ring closure. This leads to an unfavorable distribution of the pea gravel leaving the segmental lining partially without bedding. Segmental linings can develop sufficient resistance only when properly bedded."

Jan 1, 2015