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By Heithecker R. E.

In June 1933 the Bureau of Mines, in cooperation with the State of Oklahoma and the Oklahoma City Chamber of Commerce,, published a report of the gas reserves in the Oklahoma City oil field3/ based upon data as of October 1932, at which time there were 43 classified gas wells in the field, The estimates were obtained by the ?porosity-area" method. There are two general methods of estimating natural-gas reserves. The porosity-area method, as used by Hill and Rawlins, is used when a gas field is comparatively new but after enough drilling has been done to determine the average thickness, porosity, and areal extent of the producing horizon. The "pressure-volume? method of estimating gas reserves, the method used in this report, may be used after a sufficient volume of gas has bean withdrawn from the reservoir to cause an appreciable decline in reservoir pressure.

Jan 1, 1937

By W. F. Hower, W. Brown

Large-scale sand consolidation tests were conducted in an effort to determine the reasons for the successes and failures of this method of sand control. Several different consolidating materials were used in treating both clean and bentonitic sands that were packed in a chamber having a capacity of 3.3 cu ft. The results were essentially the same for all of the different consolidating materials, The data show that low-viscosity consolidating materials pumped at a relatively slow rate gave the best results. Where the formation has produced sand, the treating fluids can compress the formation, thus permitting the channeling of fluids to another horizon. Pressure-packing these zones before attempting to consolidate is recommended. Sands containing more than 4 per cent of water-swelling clays are not good candidates for consolidation. It is indicated that loose sand, particularly when it is bentonitic, can be fractured during the placement of the treating fluids. INTRODUCTION Sand production in oil and gas wells has plagued the industry for many years, and numerous cures for this problem have been suggested. Most methods have been successful to a certain degree, but the great variety of well conditions that exist in the different areas has magni- fied the problem and limited the successful use of the various systems. Four review papers1-4 present a wealth of information concerning the degrees of success that have been obtained by the different sand-control methods. The bridging of sand grains by the use of gravel packs and screens has been quite successful. However, these methods do not leave the casing clear for all types of multiple completions, and the cure does not last for the production life of the well in some instance:;. The control of loose sands by sand consolidation with resins has never been as successful as desired. It has always been hoped that such a treatment would eliminate all sand problems for the life of the well, but. initial applications, starting in the middle 1940's, were only moderately successful. Lott, et a1,3 reported a success ratio of approximately 50 per cent and made the following conclusions. The highest percentage of successes were obtained where: a. Consolidation of a zone was made at the time of initial completion or prior to the production of sand. b. The interval treated was less than 12 ft in length. c. Between 30 and 50 gill plastic/ft of producing interval was displaced through the perforations. REASONS FOR SAND CONSOLIDATION FAILURES Our own experiences in the field of sand consolidation point toward the following conditions as the major reasons for the failure of sand consolidation attempts. 1. Mud-plugged perforations and mud invasion of the formation. 2. Sand in the casing covering all or part of the perforations. This sand could be either formation sand or one of the coarser sands used as propping agents in hydraulic fracturing. 3. Holes in the casing. 4. Channels behind the casing. 5. Attempting to treat too long a perforated section. 6. Too high a percentage of water-swelling clays in the formation. 7. Formations that have produced sand. Recent attempts were made to treat perforated sections ranging from 10 to 30 ft, in wells that have produced sand, by using a straddle packer that was raised and lowered through the perforations as the consolidating material was being pumped. In most instances, the pressure required to pump fluid into the formation varied considerably as the tool was raised and lowered. This suggested the possibility that significant differences in permeability were present or that only part of the formation had produced sand. There were times when a sudden break in pressure indicated that a fracture was being formed. Research conducted several years ago concerning the problem of the control of water in air and gas drilling indicated that shale sections could be fractured quite easily. In addition, it was determined that it was easier to pump fluids into shale bodies by fracturing the shale itself, or the interface between the shale and sand, than to pump into a fluid-saturated formation. Formations that produce sand are usually adjacent to shale bodies and frequently have shale streaks of various thicknesses inter-bedded in the sand. Therefore, where shale is exposed to fluid pressure it

By G. W. Healy

G. W. Healy (union Carbide Metals 0.)-The author's paper is a useful contribution to the store of maps of chemical activities of oxides in multi-component slag systems. It is also a good example of the utility of the Gibbs-Schuhmann technique for calculating activities in a system where that of one of the components has been measured. This paper Koh and Caugherty. This plot is reproduced by alor in X-ray Metallography. Because of this nonlinearity, preparation cf suitable standards and/or correction for absorption and enhancement are essential in microanalysis. However, our objection is not the conclusion that Dr. Aaronson has arrived at nor the technique he has used; but only to the foot-note credited to V. Macres. The level of chromium that he was concerned with (less than 3 pet) is so low that the deviation of uncorrected Cr-curve will be negligible. Besides Dr. Aaronson has used chromium intensity from martensite and set it equal the bulk chromium content of the alloy. Using this chromium-intensity as a reference, he has calculated the amount of chromium in the ferrite. This amounts to the same as using an internal standard. Since the chromium content in austenite and ferrite are almost the same, enhancement due to iron in both will be the same and therefore does not need to be corrected. together with the author's recently published one1 on the CaO-FeO-Fe2O3 system will be most helpful to others learning to apply Schuhmann's method, which merits a far wider application than it has received to date and should greatly aid our understanding of equilibria between metal and oxide phases. As shown by okcen" its use may even be extended to sections of systems with any number of oxides. I have some questions as to the selection of equilibrium constants made by Dr. Turkdogan. He has chosen one for the formation of Fez03 from FeO and oxygen which gives Fea3 activities 50 pct higher

Jan 1, 1963

By M J. Davies, R S. Davies

Despite increased expenditure, the global discovery rate of world-class ore deposits has been in decline for over a decade (Schodde, 2017). Mineral exploration has traditionally followed an empirical approach, searching for evidence of mineralisation upon the surface of the planet, then drilling to define the extent of an ore body beneath the surface. As outcropping deposits in well-defined areas are depleted, there is a need for exploration to extend to less well-explored search spaces. One popular new frontier is exploration at greater depths beneath the Earth's surface. However, exploring for deep deposits with limited surficial evidence requires the implementation of predictive targeting methodologies (Hronsky, 2011; McCuaig & Hronsky, 2014). The Mineral Systems Concept (Hronsky & Groves, 2008; McCuaig et al., 2010) provides a framework for predictive exploration targeting. Ore deposit formation is recognised to be a focused mineralising event. These events represent self-organising critical systems and are underpinned by the interaction of complex, non-linear processes. Through the collection and analysis of datasets that map mineralising processes, it may be possible to predict the size and location of resultant ore bodies. CITATION: Davies, M J and Davies, R S, 2018. Beyond below-ground geological complexity: Developing adaptive expertise in exploration decision-making, in Proceedings Complex Orebodies Conference 2018, pp 95–98 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By W. Bonfield

The temperature dependence of the microscopic yield stress (the stress to produce a plastic strain of 2 x 10-6 in. per in.) and the stress-plastic strain curve of polycrystalline Cu 1.9 wt pct Be have been measured for the solution treated condition, an intermediate condition containing G.P. zones and ?' precipitate and the overaged ? precipitate condition, in the range from -58° to 200° C. A transition in micro -yield behavior and a large temperature dependence were noted for the intermediate condition, which are interpreted in terms of the interaction of glide dislocations with two differently sized zones. In comparison the microscopic yield stresses of the solution treated and overaged conditions were less sensitive to temperature variations and are satisfied by the Mott-Nabarro and dislocation bowing theories, respectively. A determination of the temperature dependence of the yield stress of a precipitation hardening alloy has provided a powerful tool for evaluation of the operative deformation mechanism. There is a marked contrast between the effect of temperature on the yield behavior of a metal containing coherent zones or intermediate precipitates, which can be "cut through" by mobile dislocations, and a metal containing a dispersion of noncoherent particles, through which dislocation "bowing out" is the dominant role of deformation.' These studies have in general been confined to single crystals, as it was considered that similar experiments on polycrystalline material did not produce good data because of the lack of sensitivity with which the yield stress could be determined. However, this objection has been removed by the introduction of mi-crostrain techniques, with which the yield stress in polycrystalline materials can be measured to a strain sensitivity of 10-6. Such measurements have not only shown that the deformation of polycrystalline precipitation hardening alloys can be examined with the same detail as single crystals, but also that some unexpected results are obtained.' In this paper the results obtained from a study of the temperature dependence of the microscopic yield stress (the stress to produce a plastic strain of 2 x 10-6 in. per in.) and the stress-plastic strain curve of a polycrystalline Cu 1.9 wt pct Be precipitation hardening alloy (Berylco 25) are discussed. The temperature dependence of the alloy was measured for three different conditions: 1) The solution treated condition (a supersaturated solid solution of a containing ~12 at. pct Be3) which is obtained by water quenching the alloy from 800° C. 2) The condition of y' intermediate precipitate, to- gether with some G.P. zones,' which is produced after an aging treatment of 2 hr at 315°C from the solution treated condition. (The alloy was cold rolled to 40 pct reduction prior to aging to minimize grain boundary precipitation effects.)4 3) The condition with equilibrium ? precipitate structure2 which is developed after an aging treatment of 24 hr at 425° C. EXPERIMENTAL PROCEDURE Tensile specimens of gage length 1 in. and with rectangular cross section of 0.18 by 0.06 in. were prepared from the solution treated, cold rolled alloy and were either resolution treated for 1 hr at 800°C, followed by water quenching, or aged for 2 hr at 315°C and 24 hr at 425° C to produce the desired precipitate structures. The microstrain characteristics of the aged specimens were determined at temperatures from —58" to 200° C and those of the solution treated specimens from -58° to 30° C. Each temperature was controlled to ± 0.2°C, which was a level of stability sufficient to eliminate thermal expansion effects from the measurements (~1.2°C temperature increase produced an extension of 2 x 10-6 in.). The microplastic behavior of the specimens in the temperature range below 82" C was measured with a standard Tuckerman strain gage,5 while at temperatures above 82°C a modified Tuckerman gage with a reduced strain sensitivity (4 x10-6 in. per- in.) was used. A load-unload technique was used to establish values of the microscopic yield stress. The specimen was strained at a constant cross head speed of 2 x 10-2 in. per min to a given stress level, at which the total strain was measured. Then the specimen was immediately unloaded at the same rate and any residual plastic strain determined. This procedure was repeated for an increasing series of stress levels until the microscopic yield stress was established by a direct measure of the stress to produce a residual plastic strain of 2 x 10-6 in. per in. (It should be noted that, as reversible dislocation motion occurs at stresses less than the microscopic yield stress,2 the plastic strain rate at this level was not constant.) In an ideal test, the microscopic yield stress would be determined from a continuous stress-strain measurement, rather than from a load-unload sequence, in order to eliminate mechanical recovery effects.6 However, it was found experimentally that mechanical recovery was negligible in Cu 1.9 wt pct Be at small plastic strains for all the temperatures investigated, as the microscopic yield stress was independent of the number of load-unload cycles employed (i.e., the values measured for specimens subjected to different numbers of cycles was within the experimental scatter determined for specimens tested in an identical manner). Therefore, it is reasonable to consider the microscopic yield stress determined in the load-unload

Jan 1, 1969

By Christoph Mueller

Mining operations are characterized by cost pressure and cycling product prices. A high potential for enhancing efficiency is the integration of all single steps of the mining working chain into a production process structure to make advantage of an optimized flow of material and information through the ?moving ore factory?. As modern mining machinery today is controlled electronically and even already operated autonomously, a smooth and cost efficient flow of data in the mining process will be crucial for cost efficient future mine operations. Therefor, the International Rock Excavation Data Exchange Standard (IREDES) was launched by major players in the industry. The task of this initiative is to define a ?common electronic language? for easy and standardized data exchange between mining machines and central computer systems. As in other industries, this standard is expected to have significant impact on the use of automated equipment. It shall provide easy ways of using multi vendor machine installations in data controlled mining processes. At the same time it reduces cost for individual development of interfaces for all parties involved. Standardized data exchange is also a crucial precondition to integrate the mining process into enterprise level modeling, cost analysis and decision finding systems. The standard?s technical architecture is open and flexible for future applications. It uses modern XML technology enabling easy data exchange with commercial databases as well as open on line networking. The IREDES work is carried out by the initiative members working jointly together in the technical work groups. Prototyping implementations of the Drill rigs profile are currently going on. Further profiles under development cover LHD?s/Loaders/Trucks and Explosives Chargers. The first official release covering the Drill Rigs profile is planned for the end of 2002.

May 1, 2002

By G. Y. Zhou

During Zijinshan copper heap bioleaching, pyrite was leached in plenty resulting in high ferric concentration in solution. It has affected bioleaching and extraction processing greatly. It results much acid and iron in solution and bad effect to extraction processing. The paper studied the influence factors in the course of pyrite leaching and ferric ion chemical oxidation, especially studied the redox potential for copper bioleaching so as to find key factors affecting the dissolution difference between chalcocite and pyrite. The results show that the redox potential is important factor. Copper and pyrite leaching rates are 95% and 11% respectively and there is great dissolution difference between them at redox potential 700 mV (SHE). During pyrite bioleaching, the indirect action of bacteria gives priority to bioleaching cooperating with the direct attack of microbial cells attached to the mineral surface. Redox potential is determined by ratio of ferric and ferrous, ferric in solution was supplied by the way of oxidation of T. f bacteria, sufficient bacteria concentration and active character were two vial factors of controlling redox potential. It is indicated that copper can be selectively bioleached during copper bioleaching by controlling redox potential of bioleaching. The conclusion will provide theoretic foundation on balance of acid and iron during bioleaching for copper of higher S/Cu ratio. The experinment proved that bacteria activation was decreased on condition of both low pH value and intermittent aeratation during bioleaching. It resulted that the oxidation velocity of ferrous ion was decreased and redox potential was controlled. The dissolution of pyrite was depressed. It would be possible to actualize selective leaching of secondary sulfide copper ore during bioleaching process.

Jan 1, 2014

By Kr. J. Dedelyanova

Selective flocculation of iron minerals could improve the economics of high intensity magnetic separation as concomitant process. When the minerals are finely disseminated is necessary a finer grinding to be applied which generates a lot of slimes. The HIMS is not enough efficient for particles below 20 microns ? territory where the selective flocculation is already well known industrial practice, so the combination of these two methods of beneficiation can bring a higher grade at high recovery to be achieved. The dynamics and selectivity of the precipitation process is studied in batch tests with flocculant starch and dispersants sodium silicate and sodium hexametaphosphate. The influence of preliminary conditioning with nitrogen acid at pH 2 before flocculation is also investigated. Flowsheet including these two methods is tested and the distribution of iron is shown.

Jan 1, 2014

Late Palaeozoic and Late Mesozoic phases of widespread overprinting have obliterated most of the primary magnetization signature of the Tasman Fold Belt. Palaeomagnetic programs of a regional extent offer best prospects for identification and interpretation of such secondary magnetizations and for isolation of any remaining primary magnetization. In 1983 the BMR initiated a regionally oriented palaeomagnetic study of the Tasman Fold Belt to obtain palaeomagnetic constraints on the tectogenesis of the fold belt. Particular attention is being paid to the analysis of possible differential movements between suspect or- tectonostratigraphic terranes within the Tasman Fold Belt and the respect to cratonic Australia. Work has concentrated so far on the Cowra Trough-Molong High region of the Lachlan Fold Belt and the New England region. Pilot sampling has been carried out in the Gympie region. In addition Palaeozoic sequences are being studied from the Amadeus Basin and the Ngalia Basin to refine the palaeomagnetic reference frame of cratonic Australia.

Jan 1, 1987

By Herbert F. Miller

For a long time I have believed that the gas- and brick-costs of open-hearth furnaces using prodncer-gas could be greatly decreased by a change in the design of the port, which would materially reduce the first-cost of the furnace, the rebuilding-cost, and the repair-cost. The defects of the present type of such furnaces, which has clone duty for so many years, may be studied in Fig. 1, in which A A are the two air-uptakes, B is the gas-uptake, and C the end of the gas-port. In the present type of furnace, C is practically 011 the edge of the bath and therefore combustion begins to take place at that point, but has no effect until the gas passes from 5 to 10 ft. into the hearth. As the furnace grows older, C moves back by reason of the burning or falling down of the arch. The furnace reaches its highest efficiency when C has moved a certain distance, but is still near enough to the bath for the overhead layer of air to hold the gas down on the bath, and far enough back to permit combustion to take place at some distance from the bath. This latter fact means that the temperature is sufficient to melt steel at the edge of the port. From this time on, the furnace decreases in efficiency. What is the reason ? As C moves further hack, the gas is released from the gas-port at a point where there is little or no overhead layer of air. The result is that the gas floats along the roof, with the air mostly underneath it. Why the air does not stay over the gas is readily seen in Fig. 1. The lines of draft naturally run parallel to the length of the furnace. The air-uptakes being on the sides and the gas-port in the middle, most of the air will naturally be drawn along the sides of the furnace and the layer of air will be thinnest over the gas, where it is most needed.

Jan 1, 1914

By Ruixuan Zhang, Yan Li, Shusen Cheng

The high temperature distribution of the blast furnace raceway plays an important role in continuous and steady production. There are a number of techniques which have been developed for flame temperature measurements, but most of them have considerable errors and instability. To obtain more accurate results, an efficient optimization algorithm is necessary. This paper presents a novel measurement approach based on the two-color method and an optimization algorithm using images of raceway flame captured by the RGB CCD (Charged-couple Device) camera to calculate the projection temperature distri- bution. Furthermore, both the back-propagation neural network and the principal component analysis are applied to calibrate the correlation between blackbody temperature and the gray-level intensity. Experimental results obtained from the blast furnace raceway demonstrate that the proposed optimization approach performs well in the measurement offlame temperature compared with the measured temperature.

Mar 1, 2017

By E. R. Weltevreden, C. Klauber, C. Vernon

"In this paper a review of the current status in recycling technologies for cathode ray tubes is given for both the glass and phosphors. Particular emphasis is placed on the opportunities for the recovery of the rare earth elements (REE) from the phosphor coatings. This is placed in the market context of alternative virgin sources and some of the advantages and disadvantages for REE waste recovery. Future opportunities are explored and also some experimental detail on a low cost leach system is presented. INTRODUCTIONThe disposal of cathode ray tube (CRT) based colour televisions has accelerated world-wide with the development of high definition flat screen panels. The total number of colour CRT televisions that have been sold in the United States in the mid-20th century is estimated to have been over 2 billion (U.S. Environmental Protection Agency, 2007), with high current rates of disposal. It is estimated that of the 20 million televisions annually discarded, 78% are send to landfill (Nnorom, Osibanjo & Ogwuegbu, 2011). However, this easily accessible item of electronics cannot only be turned into a valuable resource using the right recovery procedures, it can also prevent the substantial environmental contamination arising from improper disposal. In this review we focus on previous and current work performed on the recycling of CRT based televisions. Due to the increasing demand for rare earth metals, the main focus will be on the possibilities and challenges of recycling the fluorescent phosphor powders on the CRT’s panel glass.CATHODE RAY TUBE’S GLASS RECYCLINGConventional cathode ray tubes consist of three main parts, the panel, the funnel and the neck (Figure 1). To produce the different colours on the screen, the inside of the panel is coated with a matrix of hundreds of thousands of small phosphor dots. Each dot is one of three types of coloured phosphors, emitting either red, green or blue light. These emit light when excited by a beam of electrons generated by electron guns located in the neck of the CRT. These beams pass through holes in the shadow mask and excite the phosphor coating on the inside of the panel, to give light of variable RGB composition, see Figure 1."

Jan 1, 2012

By B. Grinbaum, A. Mazuelos, F. Carranza, N. Iglesias, M. Avila, J. L. Lozano, G. Perez, R. Romero, M. \/aliente

Following a failure of a tailings pond darn at a mine in Andalusia, Spain, a huge effluent stream, that contained about 1 g/1 Zn and significant amounts of ferrous, ferric, calcium, copper, aluminium and manganese cations has to be treated, to prevent pollution of a nature reserve. EGMASA, as the regional government environmental agency, suggested to improve the current depuration process by recovery of the Zn from the effluent. A solvent extraction (SX) followed by electrowinning (EW) was proposed and developed to remove zinc.. A pre-treatment stage consisting in bio-oxidation of ferrous iron by using a bacterial process followed by an alkaline precipitation was employed because iron in the effluent is incompatible with both the SX and the EW processes. The SX process was developed successfully at the laboratory scale and verified in a pilot plant on-site, using two Bateman Pulsed Columns for extraction and stripping of zinc. The results were satisfactory obtaining a recovery of 90% of Zn. The process was suitable for industrial application.

Jan 1, 2008

By M Rattenbur, A B. Christie, S C. Cox

A new minerals initiative to increase the level of understanding of New Zealand's mineral resources and to promote the development of minerals began earlier in the year in a partnership pilot-project between Crown Minerals and the Institute for Geological and Nuclear Sciences (GNS). The project aims to gather a set of comprehensive geoscientific data and build a series of digital GIS packages to highlight New Zealand's mineral prospectivity. The pilot study was carried out at a regional scale, and is focussed on mesothermal gold mineralisation in the South Island. A significant amount of geological data and information was sourced from open file technical reports held by Crown Minerals and from various databases held by GNS and has now been compiled into a single GIS dataset, which will soon be made freely available to interested parties. In addition to this comprehensive data compilation, prospectivity modelling using Weights of Evidence techniques was undertaken to highlight those areas likely to contain ore deposits. It is clear from this study that the South Island of New Zealand remains highly prospective for mesothermal gold mineralisation. Many of the highly prospective areas, which also contain historic mine workings, remain open for exploration. The study not only highlights these areas, but also other areas where the potential for similar mineralisation exists, in all likelihood with no surface expression. The study has also highlighted the value of many of the open-file technical reports held by Crown Minerals and the need to carry out additional studies using this and other available data at a more detailed level, possibly as the basis for a web-based minerals information system.

Jan 1, 2002

By Richard M. Foose

Most of the roofing granules produced in Pennsylvania are made by two companies at three plants. The Advance Industrial Supply Co. has three quarries and a mill at Gladhill Station, in southern Adams County. The Funkhouser Company is actively engaged in mining, quarrying and milling at Charmian, about one mile west of Gladhill Station, and at Delta, in southern York County. These three plants produced approximately 100,000 short tons of granules in 1943. The production of rooling granules in 1937 for the whole country was only about 500,000 tons, generally indicating the large growth of the industry since that time. The fundamentals of producing roofing granules were discussed comprehensively by G. W. Josephson in a paper before the Industrial Minerals Division in October 1943 (TP 1725, this volume page 460). The purpose of this paper is to describe the actual methods of mining the rock and milling it to make roofing granules, as practiced by the three Pennsylvania plants. Mining and Milling Funkhouser Company (Delta) The Funkhouser Company, near Delta, in southern York County, Pennsylvania, operates three joined quarries and a mine in the Peach Bottom slate. The joined quarries extend 1200 ft. in a northeast-southwest direction along the strike of the slate cleavage and are about 200 ft. .wide. The working face is about 45 ft. high. The quarrying operation is rather simple: Ingersoll-Rand Jackhamers, I-in. and 1 1/4-in., with hollow drill steel, are used to undercut the quarry face with 10-ft. holes. The face is "blown" and allowed to slump on the quarry floor. Loaded by a Marion electric shovel into trucks, the shattered rock is taken to the primary crusher 2500 ft. away. In addition to the normal quarrying operations, a drift into the northeast wall of the middle quarry was begun about 1935, and has advanced about 2000 ft. since then. Rooms have been driven at angles to the drift along choice beds of slate. The drifts and rooms have a roof more than 35 ft. high and the main drift and rooms are all more than 40 ft. wide. There is no cribbing at any place in the mine. Several of the rooms were driven upward on a 5' slope and in some of them there was stop-ing. Ingersoll-Rand Jackhamers are used, and only wet drilling is practiced. When visited in January 1940, an electric shovel was operating at the head of the drift, scooping up the slate blasted out of the working face. This, too, is trucked to the primary crusher. Some of the better quality slate is saved for making slate shingles. The primary crusher, which is a No. 30 McCulley gyratory, receives the slate from the trucks and crushes it to about a-in. size (Fig. I). This product travels by a 30-in. belt conveyor to Niagara vibrating screens with 2-in. holes. The minus a-in. product moves to a storage silo by bucket

Jan 1, 1948

By Richard M. Foose

Most of the roofing granules produced in Pennsylvania are made by two companies at three plants. The Advance Industrial Supply Co. has three quarries and a mill at Gladhill Station, in southern Adams County. The Funkhouser Company is actively engaged in mining, quarrying and milling at Charmian, about one mile west of Gladhill Station, and at Delta, in southern York County. These three plants produced approximately 100,000 short tons of granules in 1943. The production of rooling granules in 1937 for the whole country was only about 500,000 tons, generally indicating the large growth of the industry since that time. The fundamentals of producing roofing granules were discussed comprehensively by G. W. Josephson in a paper before the Industrial Minerals Division in October 1943 (TP 1725, this volume page 460). The purpose of this paper is to describe the actual methods of mining the rock and milling it to make roofing granules, as practiced by the three Pennsylvania plants. Mining and Milling Funkhouser Company (Delta) The Funkhouser Company, near Delta, in southern York County, Pennsylvania, operates three joined quarries and a mine in the Peach Bottom slate. The joined quarries extend 1200 ft. in a northeast-southwest direction along the strike of the slate cleavage and are about 200 ft. .wide. The working face is about 45 ft. high. The quarrying operation is rather simple: Ingersoll-Rand Jackhamers, I-in. and 1 1/4-in., with hollow drill steel, are used to undercut the quarry face with 10-ft. holes. The face is "blown" and allowed to slump on the quarry floor. Loaded by a Marion electric shovel into trucks, the shattered rock is taken to the primary crusher 2500 ft. away. In addition to the normal quarrying operations, a drift into the northeast wall of the middle quarry was begun about 1935, and has advanced about 2000 ft. since then. Rooms have been driven at angles to the drift along choice beds of slate. The drifts and rooms have a roof more than 35 ft. high and the main drift and rooms are all more than 40 ft. wide. There is no cribbing at any place in the mine. Several of the rooms were driven upward on a 5' slope and in some of them there was stop-ing. Ingersoll-Rand Jackhamers are used, and only wet drilling is practiced. When visited in January 1940, an electric shovel was operating at the head of the drift, scooping up the slate blasted out of the working face. This, too, is trucked to the primary crusher. Some of the better quality slate is saved for making slate shingles. The primary crusher, which is a No. 30 McCulley gyratory, receives the slate from the trucks and crushes it to about a-in. size (Fig. I). This product travels by a 30-in. belt conveyor to Niagara vibrating screens with 2-in. holes. The minus a-in. product moves to a storage silo by bucket

Jan 1, 1948

By Steve Colburn

The new CRITERION Survey Systems utilize both theodolite mounted and hand held reflectorless distance meters. These are eye safe, easy-to-use, and specifically designed to endure the harsh environments characteristic to the mining, quarry and explosives industries. Survey data collected by the systems is digitally stored in a ruggedized data collector and then processed with a specialized, new Windows-based interactive software program, which can be run on any standard PC.

Jan 1, 1995

Over the last three decades, the mining industry has been moving towards more underground mechanized mining methods and the number of LHD vehicles utilised has increased. The growth of mechanization and automation has benefited both workers and the mining companies. However, due to the design of the LHD vehicle and the limitations of the operating environment, restrictions to operator visibility are inevitable. The inability of the equipment operator to see clearly (i.e. people, objects or hazards) around the machine has contributed to a number of accidents including fatal injuries. In order to identify vehicle design characteristics resulting in restricted and blocked sightlines, visibility assessments for existing machines are traditionally completed in the field using a light filament technique. Past researchers have used the light filament technique to collect obscuration zones around the equipment and to produce a 2D chart of this information. The 2D shadow diagrams have proved to be useful in highlighting potential equipment problems and have been performed repeatedly to show the potential of redesigning a part of the LHD for improving visibility. The light filament method involves manually collecting data and requires a level of judgment to be used. As a result the method is susceptible to errors and requires around three hours to complete. The objective of the current research is twofold; firstly to develop a rapid method for field visibility data collection using a laser scanner and secondly to compare results of repeat tests for both light filament and laser scanning methods. A MENSI GS100 laser scanner along with Pointscape and 3Dipsos software has been used to collect visibility information and process the data. The research aims to develop the laser scanner as a technique to rapidly evaluate the visibility profile of an LHD vehicle. Machine design changes can then be assessed quickly using these results.

May 1, 2004

By Di Yang

The influence of high density (104 -105 A/cm2) electric current pulses (70 us duration) and continuous DC (~103 A/cm2) on the flow stress and ductility in tension of a high carbon steel wire were determined at 204°, 427° and 649°C. Electropulsing (100 pulses per second) with an effective current density of 100-200 A/cm2 gave a 10% enhancement in the uniform elongation of the wire at 204°C, but had no effect at 427°C and 649°C. In contrast, continuous DC either had no significant effect on the ductility or gave a decrease. The electropulsing per se decreased the flow stress only slightly at 204° and 427°C, but gave a significant decrease at 649°C. Continuous DC increased the flow stress at all three temperatures. The present results along with those by others suggest that the enhanced ductility by electropulsing and the reduction in flow stress may be further increased by raising the effective current density through increases in either the pulsing frequency, maximum current density of each pulse or pulse duration. This could conceivably increase the reduction per pass during wire drawing or the number of passes between anneals.

Jan 1, 2001

By A. Dell’Era, E. Ciro, C. Lupi

The paper explores the recovery of indium via electrowinning from sulfate baths, focusing on the impact of different cathodic supports (AISI 316L and nickel) on process parameters such as electrolyte composition, current density, and temperature. The study compares productivity, morphology, and structure of indium deposits on both cathodes, finding that nickel cathodes generally yield better results.

Nov 1, 2023