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By Munro DL

The Mary Kathleen uranium deposit is in north-west Queensland, approximately halfway between the townships of Mount Isa and Cloncurry, at long. 1400 009 E and lat. 200 44' S. The deposit Iwas discovered by prospectors of the Walton McConachy Syndicate early in July, 1954, and climaxed a very intensive ground search by hundreds of part-time prospectors. during the uranium boom from March to July 1954ò Numerous small deposits, mostly in the vicinity of Mount Isa, were discovered in various rock environments, but Mary Kathleen is the only large deposit and, apart from a few tons of hand sorted material from the Milo lease, is the only deposit that has been worked. Exploration of the surrounding area, and proving of the economic worth of the deposit, were conducted from the time of discovery until February 1956 by a geological team camped near the deposit. Proving was carried out by drilling a pattern of vertical and inclined diamond drillholes at fifty-foot centres over the outcrop. An adit was driven eastwards through the deposit. Metallurgical research and design work in the South Australian Department of Mines Adelaide Laboratories were based on core samples and bulk samples from the deposit. The signing of a contract in March 1956 with the British Atomic Energy Authority to supply 4500 short tons of uranium oxide allowed mining to commence, and enabled the planned construction of water supply, township and treatment plant to proceed. The open out mine and plant are now serviced by a modern township, four miles away, which is connected to Cloncurry and Mount Isa by road. Although little field work has been done since the exploration phase, this paper differs in interpretation from a previous paper (Matheson and Searl, 1956) in that it is based on a revised structural inter- pretation (Compana, 1958), detailed mapping of progressive exposures in the open out, and a re-examination of diamond drill cores.\

Jan 1, 1968

By Yazen Khasawneh, Osvaldo P. M. Vitali, Mohammad Nassim

The demand for renewable energy is growing as the conventional energy resources are becoming more limited and we are more conscious about the negative impact of conventional energy sources on the environment. Wind turbines technology is evolving in a fast pace, the towers are becoming taller, and the rotors are getting larger. The challenge is to maintain the Levelized Cost of Electricity (LCOE) as low as possible to ensure a sustainable and an economically feasible energy supply. Thus, the foundation systems for wind turbines should evolve to meet the increasing load demand, while reducing the LCOE. In this paper, an innovative foundation system for onshore wind turbines is presented. The new foundation system is the conventional P&H tensionless pier foundation (PHTP) with a reinforced concrete collar at the top of the pier. 3D FEM modeling was conducted to assess the benefits achieved by adding a collar at the top of the PHTP foundation. The numerical results show a significant performance enhancement of the proposed foundation system over the conventional PHTP foundation. The enhanced foundation system also has an economical advantage because the depth of the pier can be greatly reduced while maintaining a superior performance.

Sep 8, 2021

By P. J. Deveaux, M. J. Kreczmer

The Tartan Lake deposit 12 km northeast of Flin Flon, Manitoba, was discovered in March of 1984 during the investigation of a VLF anomaly. The discovery hole intersected 16.83 metres averaging 21 gm Au/tonne. Since then, 99 holes, over 21,000 metres, have been drilled outlining 419,491 tonnes grading 11.79 gm Au/tonne in a di stinct group of mineralized lenses referred to as the Main Zone. Three other mineralized zones are known on the property but no reserves have been allowed for these, the South , East and Base Line zones. The Main Zone consists of seven parallel, east-west striking, quartz lenses. The lenses dip steeply to the north and plunge steeply west to northwest. Lens number l strikes for 160m and extends vertically to the 90m level. Within th is lens there is a 60m interval of low grade materi al. Lens number 2 is located about 5-l0m within the foo twall of Lens number I. Near surface this lens stri kes for 40m, at 200m level the strike length increases to 200 m. To date the deepest mineralization on Lens 2 has been intersected at a vert ical depth of 527m. Five smaller lenses are located in the foo twall of Lens 2 , containing gold va lues similar to the two main lenses but erratically distributed. The South Zone, located 100m south of the Main Zone, strikes east-west fo r l00m above the 100m level. The East Zone, found 230m east of the Main Zone, strikes fo r 80m and may possibly be an ex tension of the South Zone. The Base Line Zone is located 275m south of the Main Zone. Sporadic, but very significant gold intersections have been obta ined1n all three zones. Gold-bearing quartz-ca rbonate tourmaline veins are generally confined to a silicous crystal tu ff hori zon. The crystal tuff exhi bits fi ve distinct types of alteration: silicification, sericitization, ca rbonati zation, chlorit ization and pyritization. Silicification has resulted in a perasive addition of silica and the generation of multiple quartz veins. Sericiti zation is restricted to the crystal tuff. All rock units are pervasively carbonatized . Ankerite is abundant in the quartz veins and within the shear zones, particul arly those located along the chilled margin of a nearby gabbro-diorite intrusion. Chloritization is widely spread th roughout the rock units, while pyritization fo rms a broad alteration halo associated with the orebody. Sulphide accesso ry minerals associated with the gold , whi ch fo r the most part appears to be free, are chalcopyrite and pyrite. Generally, the higher grade gold values are related to an increased content of sulphides in the qua rtz veins. The average sulphide content in the deposit is less than 5 %.

Jan 1, 1986

By H. Biloni

PORE formation during solidification has recently been studied theoretically by Piwonka and Flemings.1 For the ordinary conditions of cellular solidification, these authors state that there is a difficulty in explaining the formation of pores. The difficulty arises because the conditions necessary for pore formation are not those obtained during cellular growth. Therefore Piwonka and Flemings1 had to examine various unusual possibilities in order to explain the apparent presence of pores in a cellular substructure of aluminum, taken from Doherty.2 For aluminum, Doherty and Davis3 have developed a pitting technique to reveal substructure, which depends upon the condensation of vacancies from supersaturated solution after quenching. This technique as further developed4 was used to study solidification substructures. In the case of striations, delineation of the substructure is produced by the absence of surface pitting after quenching: in the vicinity of the striations the dislocations which constitute this substructure are sinks for vacancies. In the case of the cellular substructure the experimentally observed effect is the same. However, in this latter case Doherty and Davis4 suggested that micropores associated with the cellular substructure were the agent responsible for providing sinks for vacancies. This interpretation seemed necessary for the cellular substructure because no misorientation arising from a dislocation array could be observed. It is noted especially that Fig. 1 presented by Piwonka and Flemings1 and Fig. 5 by Doherty and Davis,4 as

Jan 1, 1968

By L. L. Wyman

SINCE the presentation, by the writer, of the initial paper on the embrittlement of copper,1 the subject has been investigated further along two separate lines. The first series of investigations involves the "double-deoxidized" copper, while the second series is devoted to single deoxidizers other than those used in the investigations reported upon last year. The object of these experiments is to develop a type of copper that will show the minimum of detrimental effects after having been exposed to alternate oxidation and reduction. The fabrication of this material necessitates the use of alternate oxidizing and reducing atmospheres, at temperatures ranging up to 900° C. Following this treatment it is essential that the soundness and strength of the copper be unimpaired, even in sections of only a few thousandths of an inch in thickness.

Jan 1, 1932

By Stephen H. Stow

Economically important heavy minerals have been studied in the sediments of offshore Alabama and Mississippi. Sandy samples have been collected from a 200 square mile area from Dauphin to Horn Islands. The minerals concentrate in sediments under 10-35 feet of water and may reach 2.4% by weight. The distribution of total heavies is related to the hydrodynamics of offshore Alabama-Mississippi; the greatest concentrations are in the Gulf where the longshore current is diverted from its westerly flow. Preliminary observations indicate that the distribution of individual minerals can be correlated with wave energy, particle size, specific gravity, and morphology of the mineral grains. The coarser, lighter minerals--kyanite, sillimanite and staurolite--are concentrated in relatively low energy areas in the Mississippi Sound and at the end of Dauphin Island in the Gulf; maximum concentration for each is 34.5%, 6.0% and 43.2%, respectively, of the heavy minerals. The smaller, more denseminerals--ilmenite, rutile, leucoxene, zircon and monazite--are concentrated in high energy areas in the Gulf; maximum concentration for each, respectively, is 42.0%, 5.9%, 9.652, 10.7% and 1.3% of the heavy minerals. On the basis of a minimum concentration of 1% heavy minerals, two areas have been identified and the total amounts of different minerals have been calculated to a depth of 25 feet of sediment. The data are preliminary and in no way indicate recoverable reserves, but they do show that on the order of 20 million tons of heavies exist. These deposits should be termed "indicated resources".

Jan 1, 1975

By Rodney L. Stone

In past attempts to characterize green and dry iron ore pellets, the authors have found large variations in the results of strength tests performed on closely sized pellets from the same batch. Where bentonite was the binder, such variations in the pellet quality were attributed to the presence of internal flaws and the nonuniform distribution of the binder. Studies have shown that pellet strength is strongly dependent on the degree of "mixedness" of the iron ore concentrate and the bentonite binder. However, before such a relationship can serve as a guide for the development of better mixing techniques and the associated economy of bentonite consumption, more precise knowledge of the bentonite-concentrate mixtures is needed. For example, what is the bentonitc distribution from pellet to pellet and within pellets?

Jan 1, 1970

By J. Hazen, R. Jenner

This project was developed at the PCS Phosphate Mine in Aurora, NC. This site includes a surface mining operation, beneficiation plant and chemical processing facility located in the coastal plain of eastern North Carolina. The phosphate ore being mined at this operation is a 10 to 12 meter (35 to 40 foot) thick colloidal deposit located approximately 30 meters (100 feet) below the ground surface. The ore is pumped to the beneficiation facility where it is separated into clay, sand and concentrate streams. The concentrate product is utilized at the chemical plants to produce a wide range of products including fertilizer, industrial phosphates and animal feed products. The Cyclone Dike Builder (CDB) project developed a technique for dewatering the beneficiation tailing sand stream and providing innovative placement for dike construction. Future material balance requirements at the PCS Phosphate mine required an improvement in tailing sand placement technique to accomplish strategic objectives. The water volume of the sand slurry forces significant quantities of sand out of the dike profile during deposition. PCS Phosphate and MetPro Supply of Florida developed a mobile high-density hydro-cyclone station to remove most of the water and significantly increase the density of the sand being placed for dike construction. This high-density sand slurry is then effectively controlled using minimal heavy equipment operation.

Jan 1, 2004

By Missy Isaman

"Mixed ground tunnels come in all kinds. In rock tunnels with possible faults and high pressure water, the challenges are many. With the advent of Crossover TBMs, contractors can minimize machine wear in such conditions while maximizing efficiency. The newest generation of Crossover is exemplified by two projects in Albania and Turkey. A 5.56 m Crossover TBM destined for Turkey’s Gerede Water Transmission will be assembled using Onsite First Time Assembly (OFTA) from within an existing tunnel. The unique machine will bore through 30 fault zones requiring the TBM to be sealable to up to 20 bar so pre-consolidation grouting can be done. If boring under pressure is required, the TBM will bore sequentially using the screw conveyor fore and aft gates. Skewing further towards hard rock, a unique 6.2 m diameter Double Shield TBM with Crossover features was designed for Albania’s Moglicë Headrace Tunnel. The machine features closure doors and a sealing system to contain inrushes of water until they can be grouted off. This paper will discuss the unique aspects of the Crossover designs, including their inception as based on past projects in difficult ground, and their utilization at the two current projects. INTRODUCTION Specialized tunnel boring machines have been made for years to tackle specific types of ground conditions. Traditional types of TBMs bore within a specific set of ground conditions. If a project is located in a competent granite face, then a Main Beam machine is a good solution. In soft ground, Earth Pressure Balance (EPB) machines are the method of choice. Years of experience and engineering advancements have made both types of machines fast and economical solutions for tunneling. Unfortunately not all ground conditions are a perfect swath of one material, and the need for a more diverse machine is apparent."

Jan 1, 2016

By P. B. Marchant

"Considerable gold and silver values are lost to flotation tailing from both the South ern Tail orebody and the Main Zone orebody,The underlying mineralogical assemblage of the two ore types is quite different. This paper describes the research strategy employed to determine an economical method to scavenge gold and silver from flotation tailing.Much of the unrecovered gold in the Southern Tail ore is associated with arsenopyrite while silver losses are probably as unliberated tetrahedrite and minor silver-bearing sulphosalts. Processing alternatives tested include bulk sulphide recovery by flotation and gravity, selective pyrite-arsenopyrite separation, cyanidation, and oxidation pretreatments such as pressure leaching and bioleaching to enhance cyanidation response. Gold losses in the Main Zone ore are more closely associated with silver-bearing minerals, pyrite, and siliceous gangue and consequently respond more readily to conventional tank cyanidation. The 5 300 tid carbon-in-leach circuit to treat Main Zone flotation tailing is described in detail.IntroductionEquity Silver Mines Limited's open-pit silver mine, a 70% owned subsidiary of Placer Development Limited, is located 37 km southeast of Houston in north central British Columbia. The deposit consists of two major ore zones, Main Zone and Southern Tail (Fig. I). These zones are within a sequence of Cretaceous volcanic and sedimentary rocks striking 015 degree s and dipping 45 degrees west. Feasibility ore reserves were 28 million tonnes grading 106 g A g/t, 0.96 g Au !t and 0.38% Cu a strip ratio of 2.2 to I. A detailed mineralogical description has been presented and a comparison of the two ore zones is shown in Table I."

Jan 1, 1986

By Peter Raziszewski

"A ball charge dynamics model is presented. Simulation results are compared with observed data showing good correlation. Based on the charge dynamics models, a liner wear model is presented along with some wear simulation results. Using the charge dynamics model with the liner wear model, it is possible to envision the predictions of mill power consumption as a function of liner wear. Further work is needed to validate the liner wear model.IntroductionFrom a process control point of view, industrial systems can be considered stationary or non-stationary. For example, the physical properties, such as geometric and/or material, of a system considered stationary do not change with time. However, this is not true for non-stationary systems such as those found in the mining industry where process dynamics are often violent with wear being an intrinsic process phenomenon.In this paper, a model for ball charge dynamics will be presented along with a description for liner wear. Simulation results for power draft prediction using the charge model will be compared with observed data. Further, liner wear results will also be presented."

Jan 1, 1997

By Louis A. Panek

INTRODUCTION AND SUMMARY With respect to the geomechanics aspects, the primary technical objectives in mining by an undercut-cave method are to achieve a controlled, sustained caving of the mineral body and to remove the fragmented ore with a minimum of dilution from surrounding unmineralized rock, while maintaining stability or control of the rock structure around the access openings. The structurally ideal ore body probably does not exist. If the rock mass is so weak as to cave on a short span, it may tend to be too sticky for easy drawing and handling, or create special problems in regard to support of the access openings. If the ore is strong, caving may be difficult and the caved fragments may be of such a large size as to require special equipment for transferring the ore from the caved zone. Given enough time and money to generate data and conduct trials, engineering and ingenuity can devise an appropriate combination of mine layout, sequence of extraction, and mechanical equipment to achieve a technically successful caving extraction operation to meet the foregoing requirements in many types of deposits. The large capital investment involved, however, reduces the freedom to make major changes once the mine development is well under- way, and the penalties for failure to accurately anticipate operating conditions militate against selecting any but the most obvious candidates for mining by an undercut-cave method. The demonstrated capability to extract large, deep, economically marginal deposits by this low-cost, high-volume method of mining provides an incentive to develop a rationale for predicting the cavability and stability characteristics of a deposit prior to mining, so that the undercut-cave method may be extended to a much wider range of mineral deposit characteristics. The ultimate goal is to establish as explicitly as possible the quantitative interrelationships between the measured rock-mass characteristics, the caving span, the size distribution of caved ore fragments, and the sizes and locations of stable access openings. Lacking an understanding of these relation- ships, a designer may readily change some factor in the wrong direction (e.g., excessively reduce the distance between the extraction level and the undercut to increase the convenience of operations for the undercutting crew, increasing the frequency of repairs to the extraction-level support system) or create unnecessary problems elsewhere in the system by introducing a design change that can achieve only minimal improvement in the factor of direct interest (e.g., unnecessarily complicate the ore-transfer system by changing the orientations of the openings, with- out succeeding in the objective of improving the ground support conditions). Although successful predesign is the prime objective, subsequent modifications in mine lay- out and sequence of extraction operations are inevitable. In developing the modified solution, systematic experimentation based on an understanding of the underlying structural relationships, coupled with monitoring measurements of selected diagnostic structural-behavior parameters, can achieve an acceptable solution in a minimum number of steps, which is far superior to the typical operational trial-and-error approach, in view of the cost of implementing each successive change. Since a drill-core sample of ore rock from a successful undercut-cave operation may exhibit a uniaxial crushing strength in excess of 100 MPa, the caving of such a rock mass is now commonly believed to be ascribable to the presence of discontinuities such as joints or fractures throughout the ore body. An essential part of the present investigation was therefore to characterize the natural discontinuities at each of the test sites by measuring their attitudes and spacings. The term "fracture" is used herein in a general sense to include any planar discontinuity without implication as to its suggested mode of origin. Most, but not all, of the fractures are properly termed joints. As a point of departure we may consider the possibility that the rock mass is transected by three families of joints, each family possessing a distinct orientation, such that parallelepipeds of intact rock are delineated by the jointing. Even if cementation is absent between adjoining parallelepipeds, the undercutting of the rock mass will not necessarily initiate sustained caving--owing to the all-around confinement, an arch may tend to stabilize over the undercut unless prevented from doing so by the failures of key blocks of intact rock. Thus, although the jointing can be assumed to weaken the rock mass, creating preferred directions of

Jan 1, 1981

By K. Hanumantha Rao, K. S. E. Forssberg, A. Vidyadhar

Using pure albite and quartz minerals, the separation of albite from quartz using mixed cationic/anionic reagent schemes is assessed through Hallimond flotation, zeta potential and diffuse reflectance FTIR studies. The reagent schemes are tested in bench-scale flotation for the separation of albite from Greek Stefania feldspar ore. The single mineral flotation tests showed the feasibility of selective albite flotation from quartz at around pH 2 using a mixture of cationic diamine and anionic sulfonate collectors or a combined cationic-anionic collector of diamine-dioleate. In contrast to the selective flotation response of albite at pH 2, where albite is slightly negatively charged and quartz possess zero charge, the zeta potential and FTIR studies elucidate similar adsorption behavior of mixed collectors on both of the minerals. The infrared spectra not only showed the co-adsorption of anionic sulfonate or oleate with diamine on the surface but also showed that the diamine adsorption increases with the presence of anionic collector. The intrusion of anionic collector in between adjacent surface alkyl ammonium ions decreases electrostatic head-head repulsion, thereby increasing the diamine adsorption by increasing the hydrophobic tail-tail bonds. The discrepancy in the flotation and adsorption results at pH 2 is attributed to the coarse and fine size particles employed in these studies, respectively. The comparable adsorption on fine particles of albite and quartz at pH 2 is explained by the interaction of ammonium ions on silanol groups by hydrogen bonding besides electrostatic interactions. The bench-scale flotation results indeed showed that selective albite flotation takes place only after desliming the feed material. An albite concentrate exceeding 10% (by weight) Na20 is produced from a material containing about 6.5% (by weight) Na20, where an albite product of more than 9% (by weight) Na20 is considered to be valuable. Key words: Flotation, Adsorption, Zeta-potential, FTIR

Jan 1, 2003

By Hisaaki Takada, Atsushi Yoshida, Kazuo Satoh, Norikazu Nanko, Naoshichi Higashi

Kamioka Mine of Mitsui Mining & Smelting Co., Ltd. is the largest lead-zinc mine in Japan and is composed of two mines, Tochibora Mine and Mozumi Mine, which have daily production rates of 5,200 metric tons and 1,800 metric tons of crude ore respectively. In the mines, there are many massive pyro-metasomatic deposits which have been derived from the replacement of limestone. The deposits are composed of skarn minerals which mainly contain hedenberite. The country rock is generally hard and fine-grained gneiss. These deposits have been mined by means of the sublevel stoping method, induced block caving method and sublevel caving method at Tochibora Mine and mainly by the cut and fill method at Mozumi Mine. Since the 19601s, the trackless mining system has been introduced successfully into both mines, and is still promoted to be applied over wider areas. The underground hauling system is simplified remark- ably and much improved by adopting trackless ramps to the existing vertical and horizontal underground framework. Moreover, through the combination of the trackless mining system with the mining methods stated above, a notable increase in efficiency has been achieved. This is due to the high performance of the introduced machinery, reductions in man power of miscellaneous jobs, and also has enabled a highly efficient performance through its mobility. In addition, as it becomes possible to realize a flexible development to meet the irregularly shaped deposits and also becomes much easier to recover the remaining pillars by secondary mining, the extraction rate of ore has been improved considerably. With the introduction of the trackless mining system, the development method has been changed, thus former hand-hold leg-drills are now mostly re- placed by jumbo-type drills. Repair shops for Load-Haul-Dump machines also have been provided with an established service system. Reinforcement and rearrangement of the ventilation system has been carried out.

Jan 1, 1977

This paper outlines a range of strategies for steady state optimisation of most types of concentrators. Optimisation is considered in terms of comminution performance, energy efficiency, concentrator strategy and overall mine/concentrator operating philosophies. Application becomes more complex as the range of optimisation is expanded. However, the potential gains also increase. A step by step framework for data collection and analysis is provided. This process is facilitated by powerful simulation and mass balancing programs which are now in common use. Once a sound, steady state rationale for optimisation has been developed, it may be used to provide a fine foundation for process control system development.

Jan 1, 1993

The early history of coal in West Virginia is all included with that of Virginia in the few records available but for present-day readers it is much more convenient that the account of this area prior to the Civil War be grouped with that since then. West Virginia shares with Maryland in the first record of coal noted in the Appalachian fields. This was along the upper Potomac River, in the fall of 1736, and the data about it are given under Maryland, as most' of the development of the area was in that state. The next record of coal was left by John Peter Salley in his account of the expedition he made with Howard and others in 1742. (See p. 17.) The next reference found is that of Dr. Thomas Walker, in 1750, when he passed through the Pocahontas coal field. This has been described on page 18. Six years later, in March 1756, Capt. William Preston, who was with Major Lewis in his expedition down Big Sandy River, wrote in his journal: "Tuesday 2.... Moved down the branch and- came to the main creek where we camped. Put on half rations. Came into the Cole land; crossed the river 8 times."1 The party crossed from the head of Clinch River to Horse Pen Creek, then to Jacob's Fork and down it to Dry Fork of Tug River; the coal was seen in what is now McDowell County. The early settlers must have known of the presence of the great Pittsburgh bed in the northern part of the state, both along the Monongahela River and elsewhere, because the outcrops could easily be seen along streams in many. places. The report of the Commissioners for Adjusting Claims to Unpatented Lands, made in 1789, contains several references to coal in the names of streams, made years earlier. The earliest is one for 1,000 acres to James Walker, in Monongalia County, "adjoining his settlement on a branch of the right hand fork of Pappaw known by the name of the Stone Cole Lick made in the year 1773."2 Another of 400 acres in the same locality was settled upon in 1777.2 A third spoke of a tract "on the left hand fork of Stone Cole about three miles from the mouth," in 1783.1 Monongalia County then covered all of the northern

Jan 1, 1942

By I. J. Logan, Warren L. Baker

By 1950 or soon thereafter facilities will be available in foreign countries for the production, transportation, and refining of about 4,305,000 bbl per day of crude oil—a volume not far short of current United States output. This is indicated by announced plans for foreign expansion, - some of the work being already under way. The projected potential production is about 1,500,000 bbl per day or 50 pct above the record-setting foreign production of 2,810,000 bbl daily in 1946. The scheduled new foreign facilities are equivalent to almost one third of the present facilities of the United States. Fears that so much additional foreign oil may flood world markets and disrupt the domestic industry of the United States are not justified. The projected foreign expansion apparently has been planned on a sound business basis, with careful consideration of the world's actual need for all the projected additional production. Materially increased world demand for petroleum promises to absorb the increased supplies without ill effect upon the domestic industry. Even by applying conservative estimates of both foreign and domestic demand, it is indicated that world requirements can absorb the projected larger foreign output and still permit continued increase in United States production. World demand would have to increase only 5.7 pct per year in the 1947 to 1950 period to absorb the prospective supply. Such an increase may be conservatively projected, in view of past and current trends. Introduction Recent announcements of plans for expanding petroleum facilities in the Middle East and Venezuela foreshadow an unusually sharp increase in foreign production in the immediate future. Therefore, the next few years will bring far-reaching changes in world petroleum affairs, with foreign petroleum production and other activities assuming much greater importance than formerly. Tabulation of figures on development already under way or planned indicates that in the next several years facilities will be available for producing, transporting and refining twice the prewar production of foreign fields and about 50 pct or nearly 1,500,000 bbl a day above their record-level output of 1946. To say that foreign fields may be producing such an enlarged quantity by 1950 is, of course, a statement of great significance to everyone connected .with the oil industry and especially to those of the American petroleum industry. A production of 1,500,000 bbl daily is equal to the combined yield of the states of Oklahoma, Kansas, Illinois, Louisiana, Arkansas, Mississippi and New Mexico. This means that within the next several years foreign petroleum facilities will undergo a new expansion equivalent to one third of the present facilities of the United States. To think of such an expansion in foreign production is to raise at this meeting the question of what this prospective foreign development means for the United States, the American petroleum industry in general, and the American engineer and technologist in particular. It is only logical to question whether or

Jan 1, 1948

By Warren L. Baker, I. J. Logan

By 1950 or soon thereafter facilities will be available in foreign countries for the production, transportation, and refining of about 4,305,000 bbl per day of crude oil—a volume not far short of current United States output. This is indicated by announced plans for foreign expansion, - some of the work being already under way. The projected potential production is about 1,500,000 bbl per day or 50 pct above the record-setting foreign production of 2,810,000 bbl daily in 1946. The scheduled new foreign facilities are equivalent to almost one third of the present facilities of the United States. Fears that so much additional foreign oil may flood world markets and disrupt the domestic industry of the United States are not justified. The projected foreign expansion apparently has been planned on a sound business basis, with careful consideration of the world's actual need for all the projected additional production. Materially increased world demand for petroleum promises to absorb the increased supplies without ill effect upon the domestic industry. Even by applying conservative estimates of both foreign and domestic demand, it is indicated that world requirements can absorb the projected larger foreign output and still permit continued increase in United States production. World demand would have to increase only 5.7 pct per year in the 1947 to 1950 period to absorb the prospective supply. Such an increase may be conservatively projected, in view of past and current trends. Introduction Recent announcements of plans for expanding petroleum facilities in the Middle East and Venezuela foreshadow an unusually sharp increase in foreign production in the immediate future. Therefore, the next few years will bring far-reaching changes in world petroleum affairs, with foreign petroleum production and other activities assuming much greater importance than formerly. Tabulation of figures on development already under way or planned indicates that in the next several years facilities will be available for producing, transporting and refining twice the prewar production of foreign fields and about 50 pct or nearly 1,500,000 bbl a day above their record-level output of 1946. To say that foreign fields may be producing such an enlarged quantity by 1950 is, of course, a statement of great significance to everyone connected .with the oil industry and especially to those of the American petroleum industry. A production of 1,500,000 bbl daily is equal to the combined yield of the states of Oklahoma, Kansas, Illinois, Louisiana, Arkansas, Mississippi and New Mexico. This means that within the next several years foreign petroleum facilities will undergo a new expansion equivalent to one third of the present facilities of the United States. To think of such an expansion in foreign production is to raise at this meeting the question of what this prospective foreign development means for the United States, the American petroleum industry in general, and the American engineer and technologist in particular. It is only logical to question whether or

Jan 1, 1948

By Kristine Bruce Wanderley, Denise Crocce Romano Espinosa, Jorge Alberto Soares Tenorio

Magnesium is present in nickels leach liquor and it is often disposed in waste barriers. However, new technologies with the aim of recuperating magnesium and other metals in the liquor have proven that it is possible to reduce the amount of metal lost during nickel ore processing. In this context, high temperature crystallization removes magnesium, with a concentration of 8 g/L, as MgSO4 H2O from the leach liquor. Kinetic studies of this process are needed to evaluate the thermodynamics of the growth of crystals. Thus, this work aims to study the crystallization kinetics of MgSO4 H2O. Temperatures of 230, 210 and 200 °C were investigated in a batch crystallization system in solutions with pH2. Aliquots were taken at each hour up to 5 h of time residence and analysed by ion chromatography for magnesium concentration. The reaction mechanism as well as rate constant and activation energy for each reaction temperature were obtained

Mar 1, 2018

By J. J. Krizek, A. H. Ditto

INTRODUCTION The Carr Fork property is situated in the Bingham Mining District located on the east slope of the Oquirrh Mountain range in Utah. The mine is adjacent to and lies west of Kennecott's Bingham Pit some 25 miles southwest of Salt Lake City. The Bingham Mining District contains one of the largest copper reserves on North America. Mineralization is associated with the Bingham stock which intruded through some 16,000 feet of sedimentary formations. Mineralization and a1teration zoning was developed radially from the Bingham stock with lower grade disseminated copper mineralization centrally located in the stock and adjoining quartzites. In addition, several garnetized limestone beds abutting the stock were also well mineralized. These skarns will be Carr Fork's initial mining target. Of the several limestone beds, only two, the Yampa and the Highland Boy have significant commercial interest at present. These beds which are 50 feet to 150 feet thick and are separated by 200 to 400 feet of quartzite were highly folded, thrusted and faulted, resulting in a dip variance from 20" to vertical. The predominant dip, however, is between 20" and 45" from horizontal. Quartzites surrounding the limestone beds were subjected to the same degree of tectonic activity with resultant intense fracturing and stress relief. The limestone beds which have a higher elastic modulus and which also experienced fracture healing during mineralization appear to have greater competency and strength than the quartzites. Four shafts nominally 3500 feet deep will provide access to the mine which will be a highly mechanized trackless operation, designed to produce 14,000 tons per hoisting day. First production is scheduled for the last quarter of 1979.

Jan 1, 1977