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By Neha Shukla, Nikhil Dhawan

The current study examines the extraction of rare-earth elements from trichromatic phosphor of discarded tube lights via baking processes. The Y2O3: Eu3+ (YOX) and BaMgAl10O17: Eu2+ (BAM) phases completely decomposed during acid and alkali baking with > 90% Eu and Y extraction. Prior, selective acid leaching of the YOX phase enhanced the acid baking process at a lower temperature (< 230 ℃). Feed acid baking showed a maximum 87% Tb, 36% La, and 17% Ce extraction at 500 °C, 0.5 h, 1 ml/g H2SO4, and alkali baking yielded 16.1% Tb, 86% La, and 73% Ce at 300 ℃, 0.5 h, 50 wt.% NaOH. The acid baking of the acid-leached phosphor yielded 72% Tb, 95% La, 63% Ce, ~ 95% Y, and Eu extraction at 300 °C, 0.5 h, 1.05 mL/g H2SO4. Lower Tb extraction during the acid baking of acid-leached phosphor can be attributed to the formation of Ba3Tb( PO4)3 and BaTbO3 phases. Insoluble Si3Tb5 phase formation and partial decomposition of CeMgAl11O19: Tb3+ (CMAT) phase in the alkali baking route leads to lower Tb extraction. The acid baking process is suitable for extracting Tb, Eu, and Y, whereas the alkali baking process is suitable for La and Ce. The thermal analysis of phosphor and flux interaction depicts that alkali baking is less energy-intensive than acid baking. In comparison, the one-step acid baking process and the two-step alkali baking process yielded desirable extraction results (87% Tb, total RE (rare earth) 78.5% and 50.4% Tb, total RE 59.3%). The product yield in the acid and alkali baking route of feed, acid-leach phosphor is 36%, 29%, and 39%, 28.2%, respectively, with ~ 98% mixed rare-earth oxide purity.

May 5, 2022

DR. BANOWSKY: Thank you very much. That was the shortest introduction that I have had lately, and I didn&apos;t have time to get my coat on. But I appreciated it, and I&apos;m delighted to be here with an industry with which 1 feel strong affinity. At the University of Oklahoma we have an energy history. We are a little more currently involved in oil and gas, and those of you who know the history of our state would be aware we have an early coal development back really before the turn of the century in the southeast part of our state what we call Little Dixie. How many of you have spent anytime in Oklahoma or are from the state of Oklahoma? I&apos;m not going to ask how many are from OSU or the University of Colorado. We did send you a football coach here from Oklahoma, and 1 see you have exchanged him. Several of you were only interested in the lobby in asking about our football team this year. 1 would like to go somewhere where we can talk about something besides football. I&apos;m just trying to build a University that our football team can be proud of. We&apos;re going to be strong again. 1 can assure you. We&apos;ve got the best football team money can buy. It&apos;s not quite as bad as the college president who called the coach in and said, "Coach we&apos;re in trouble, you&apos;re losing games and the alumni is very unhappy." "What can we do?" the president asked. The coach said, "Well the football team is flunking the admissions test. We can&apos;t get them in with the standard achievement and SAT tests." The president said, "What can we do?" The coach said, "Well the coaching staff has substituted for the American College Test the simple fill in the blank questionnaire." The president said, "Let&apos;s use it. We have got to get the team in." The first question was, Old MacDonald had a (-). And a couple of the big tackles were taking it and one of them said, "Hey, what did Old MacDonald have?" His friend said, "Stupid, Old MacDonald had a farm." "Well how do you spell farm?" He said, "Stupid, e i e i 0." Now the gentleman who met me at the registration line from Lakewood, Colorado, was asking me about one of our great big tackles; and he is doing well. We call him Doctor Death; he is also a wrestler and that gentleman said, "1 don&apos;t know how bright he is." 1 said, "He is bright enough for our academic tutoring that he is going to get through all right." So I&apos;m delighted to see you and be here with my very dear friend, Carl Terzian. Carl and 1 were in Los Angeles together for 10 or 12 years when I was president of Pepperdine University. He and I are exactly the same age. Born in 1935 and 1 a month or two later in 1936. Fewer children were born in that period than in any other period of time in this century. For those of you who remember anything about that period, you will know why no one was having babies during that period. But Carl called and said, "Bill do you know where Vail, Colorado is?" Well when you live in Oklahoma, you learn where Colorado is in a hurry. 1 not only know this beautiful area, but have made too much of an investment here at a place called Beaver Creek. The real estate is cheap over there. 1 play regularly in the Gerald Ford Invitational Golf Tournament here. Hope you will visit Beaver Creek. It&apos;s just 10- 12 miles to the west. The sight of the 1976 winter olympics until the people of Colorado voted them out. And now Vail Associates and I are good Oklahoma families. Bass family, Harry Bass of course, many of you know this story, who is chairman of the Board of Vail Associates, is making quite an investment in that year-round resort area. Beautiful golf course now. You can come out and afford the green&apos;s fee and beautiful, beauti-

Jan 1, 1982

By D. L. Kiser

Conventional and advanced coal preparation technologies were investigated through both a literature search and through direct contact with investigators and developers. In addition to a brief description of each process, performance characteristics including feedstock type, ash and sulfur reduction, thermal energy recovery and cost are provided in a tabular form. Seven of the most commonly utilized conventional coal preparation processes, including those respectively accepting coarse, intermediate and fine coal feed, were reviewed. It was found that certain properly implemented and well maintained conventional processes were capable of better than 75 percent ash removal while recovering 90 percent or more of the inherent thermal energy. Almost 50 advanced coal preparation processes were investigated based on biological, chemical and physical principles. Physical processes investigated included cycloning, homogeneous heavy media, electrostatic, high gradient magnetic, flotation and selective coalescence. Using pulverized coal as a feedstock, some of these processes are respectively reported to be capable of removing better than 95 percent ash. 95 percent pyritic sulfur, and 50 percent organic sulfur while incurring energy losses of less than 5 percent.

Jan 1, 1986

By R. D. Hansen

This paper discusses the influence of frother type and dosage on recovery/selectivity in coal/sulfide mineral flotation as a function of particle size. It is shown that different frother structures do exhibit quite different but consistent performance characteristics depending on the underlying particle size ranges involved as well as the dosage levels of both the frother and collector. The data presented on existing commercial frothers end some new special purpose experimental frothers is used to illustrate some general operator guidelines on proper frother selection and use.

Jan 1, 1985

By D R Quick

The Goodall gold mine is located 30 km east of Adelaide River, within the Pine Creek 1:250 000 map sheet, at 8 525 000 mN: 750 000 mE, on the AMG grid. The first gold was poured in April 1988 and the mine closed in September 1993, having produced 228 400 ounces of gold from 4.095 million tons of ore, at a head grade of 1.99 g/t. Oxide and primary ore was mined from one large open cut and low grade oxide ore from three smaller pits. The gold mineralisation was discovered in 1981 by means of a helicopter borne rock chip sampling survey, which delineated 13 discrete anomalies. Systematic grid sampling of rock chips outlined an area of 1300 m by 300 m within the 2.0 g/t contour. Over 7500 m of costeaning was used to delineate the A and B-Pod mineralised areas. Geochemical soil sampling played only a minor role in the discovery and geophysics none at all. By the end of 1984, 40 diamond drill holes had been completed and a resource of 3.63 million tonnes at 3.0 g/t calculated. In January 1985, Western Mining Corporation Ltd became a joint venture partner and funded exploration to cam a 60 per cent interest. Additional drilling led to a feasibility study in 1987, based on a Measured and Indicated resource of 4.25 million tonnes at a grade of 2.35 g/t. The host rocks are quartzo-feldspathic wacke and interbedded phyllitic siltstone, of the Proterozoic Burrell Creek formation. The main zone of gold mineralisation, A-Pod, occurs in a sub-vertical vein array, up to 50 m wide and 800 m in length, of quartz and sulphide veins (5-20 mm wide), It is parallel to and on the east limb of an upright, north plunging anticline. Five types of veining have been recognised, with the bulk of the gold mineralisation associated with quartz-pyrite-arsenopyrite and chlorite-quartz-pyrite veins. The gold occurs as particles, from 1-20 micron, as inclusions and along fractures in pyrite and arsenopyrite and to a limited extent in chlorite. The mineralisation is epigenetic and structurally controlled by fractures developed during an earlier folding event. The gold is assumed to have been derived from the underlying sediments of the Koolpin Formation by hydrothermal fluids emanating from the deep seated northern margin of the Cullen Batholith. Precipitation of gold may have been controlled by variations in temperature and pressure.

Jan 1, 1994

By B. M. Hamilton

"IntroductionTHE PROCEDURE and technique for drilling holes has probably undergone as great a change during the past ten years as any one of the other operations conducted in hard-rock mining. During this period, we have seen a change from the heavy leyners and drifters to the light jackleg type of drill machine; from steels that were forged and hardened on the bit end to the inserted •carbide-tipped rod, from the necessity of providing special bit-end fabrication and beat treatment of shank steels to the simple grinding or turning of a plain section on a shank with no heat treatment required for bit attachment.When the steel maker was first called upon to manufacture a hollow drill rod, it was required that the steel must not only have sufficient strength and fatigue resistance to cope with the stresses of service, but also must be capable of being heat treated on the bit end to a high hardness for resistance to wear and abrasion . Little was known at that time about alloy steels and the beneficial effects to be gained from additions of chromium, nickel , and molybdenum. So it was that the plain 0.80 per cent carbon analysis was selected, since it had already proven to be a suitable grade for chisels, hammers, and other such shock tools. This grade has long endured the test of time and is still used in considerable tonnage today, particularly by the construction industry.As the metallurgist learned more about the influence of alloying elements, a new hollow drill analysis was placed on the market in the early 'thirties'."

Jan 1, 1954

By Denis Bois

La Bolivie est un pays en développement qui compte une tradition minière qui précède même l?établissement espagnol en Amérique. Pendant toutes ces années, l?exploitation minière s?est faite sans grands égards pour l?environnement. Au cours des dernières années cependant, le gouvernement bolivien a modifié ses lois afin de rendre nécessaire la prise en compte de l?environnement dans le processus d?exploitation d?une mine. Dans le cadre d?un projet MRN-ACDI1 visant à renforcer le secteur minier en Bolivie et ses retombées pour la population, l?URSTM2 a été mandaté pour développer et mettre en place un programme académique de gestion environnementale minière, basée sur l?expertise canadienne. Ce programme vise à renforcer les institutions académiques boliviennes responsables de la formation en environnement minier en Bolivie ainsi que les ministères et agences gouvernementales concernées.

May 1, 2001

By Russell Clough

The Pacheco Pumping Plant is situated on the west end of San Luis Reservoir in western Merced County, California. It is designed to draw water from the reservoir and pump it into a 3,500,000 gallon regulating tank. The water then flows entirely by gravity to the Coyote Pump Station in Morgan Hill, a distance of 40 miles, where it is pumped into Anderson Reservoir. This water is used to recharge the depleted groundwater table in the Santa Clara Valley. Eventually, some of the water will be diverted to Hollister in San Benito County and to Watsonville and Santa Cruz in Santa Cruz County. The owner is the United States Bureau of Reclamation. The underground work consisted of a fifteen foot finished diameter surge shaft 250 feet deep to the crown of the pump chamber; a twenty foot finished diameter pump chamber which declined from the shaft at 14.2% for ninety feet and then ran horizontally for 180 feet; and twelve each five foot diameter steel lined intake shafts 240 feet deep which intersect the pump chamber in the horizontal section. (Figure 1) Upon completion of the pump chamber, the contractor had to dewater the existing tunnel under the reservoir, excavate the remaining fifteen foot plug, and concrete the transition. The low bidder for this contract was Underground - Continental-Heller at 414,456,000. Excavation of the open cut for the pumping plant and surge shaft began on April 14, 1983. This was performed using a Koehring 1066D backhoe, dozer, trucks, and two Cat 631 scrapers. The excavation was started at the surge shaft so that the grouting could begin

Jan 1, 1985

By Edmond Chin

The area encompassed by the political entities included in this study com-prises 11 million square miles or about 15 percent of the total Earth&apos;s land area. The bulk of the region is contained on the Asian continental land mass. Australia, the world&apos;s largest is-land or the world&apos;s smallest continent, alone is almost as large as the continental United States. The islands of New Zealand, New Guinea, Borneo, Sumatra, and Honshu are among the largest in the world. Collectively, they constitute a land area of 1.1 million square miles or an area about one-fourth the size of the United States. The region is noted for its great rivers. The Chang, Huang, Amur, and Mekong are respectively the fifth, sixth, eighth, and eleventh longest rivers in the world. The Ganges-Brahmaputra has created the world&apos;s largest delta, which covers 30,000 square miles. Abutting East Asia are the Sea of Japan, Dong Hai, Nan Hai, Bay of Ben-gal, and Arabian Sea. In the Southern Hemisphere, there is the Indian Ocean and the South Pacific Ocean. The Continental Shelf adjacent to the region constitutes a large proportion of the world&apos;s readily accessible shelf area. On the other hand, the Philippine and Java trenches and, further out, the Mariana Trench reach to formidable, abyssal depths, downward to 6,000 fathoms. Contrasting to this is Mount Everest, which reaches a lofty height of 29,028 feet. And then there is Xizang, whose high plateaus have been called the roof of the world.

Jan 1, 1992

By Peter Fischer

Between 45,000 and 50,000 claims for subsidence are submitted each year to the German hard coal industry. In order to improve the service to claimants a quality management was established in 2005. This paper describes the process now used for handling these claims. A quality check has also been carried out by way of a customer survey, which was performed by an independent research agency. The results of the survey are presented in this paper. In Germany, research into mining subsidence mainly involves the prediction of ground movements caused by deep mining operations. Special areas of research are subsidence reducing aspects of the extraction panel planning, especially from the point of view of mining dynamics, as well as securing and restoration measures. This work seeks to prevent or minimize mining-induced damages close to the surface, for instance, buildings or infrastructure installations (such as pipelines), or underground mine openings (e.g. shafts). Roof collapses and surface fractures caused by shallow mine workings of an earlier era currently constitute a special area of investigation.

Jan 1, 2006

By S. M. Shelton

Preliminary work in the investigation of electrolytic manganese, as reported J, showed promise for a practical procedure of continuous production. Laboratory work was continued in the direction of process simplification to determine an economically feasible procedure that mould require a minimum of expensive equipment for plant erection and a minimum of regent consumption for operation. Results furnished enough evidence to indicate that modifications of the process could be made leading to simplified procedure and with no sacrifice in operating efficiency. A supply of at least 200 pounds of the metal was desired for alloy research, and it was believed worth Mile to utilize available facilities in a search for difficulties, that were not encountered in the laboratory and that might arise in larger-scale operation. Consequently, an experimental pilot plant was erected. The plant was designed for a capacity of 15 rounds per day of metal and operated under simulated -plant practice.

Jan 1, 1938

By I. A. Minaev

The conditions of a stability of metallurgical films on a surface of solid on the basis of classical regularities of a thermodynamics are considered. For specific conditions of metallurgical processes the basic equations relevant to non-metallic inclusions (product of steel killing) migration and transfer through the interface boundary of metal-slag are obtained. The basic criteria equations of conditions of stability of metallurgical dispersed systems are developed in view of films formation. The probable thermodynamics reason of wetting due to formation of stable films are discussed. The experimental measurement of thin and thick films elastic resistance for metallurgical systems are carried out and the results are discussed. The presence of a wetting thick film increases stability of dispersed systems (facilitates an inverse implication of non-metallic inclusion in a melt) due to a barrier effect of wetting films. The quantitative evaluations of non-metal inclusion stability for steel in contact with any metallurgical slag are carried out. The results are in accordance with technological experience. Keywords: Inclusion removal, Film thermodynamic, Slag-metal dispers system

Jan 1, 2004

By George L. Richert

The Minas de Matahambre is situated on the north coast of Cuba, in the Province of Pinar del Rio, approximately 150 miles west of Havana. This nine is the only producer of copper in Cuba, and has been worked for the past 15 years. In 1921 the property was affiliated with The American Metal Co., Ltd., and has been worked by them since that time under the direction of Mr. D. D. Homer, General Manager. Extracts from P. D. Wilson&apos;s ?Preliminary report on the geology at Minas de Matahambre? have been freely used in this report.

Jan 1, 1929

By F. Habashi

Siberia, a vast country rich in mineral resources and a large number of different ethnic groups. To the east of Lake Baikal is Buryatia with capital Ulan Ude. The Buryat are closely related to the Mongolians. Ulan Ude is connected to Ulaan Baatar (Ulan Bator) the capital of Mongolia by train – a 26 hours trip. Getting a visa to Russia is not a simple case. Visits to metallurgical research laboratories, Lake Baikal, and historical museums are enriching experience.

Jan 1, 2006

By Lloyd Williams

A vertical air shaft in the Birmingham, Ala., iron district was sunk with a circular cross section and lined with concrete at a relatively low cost to provide needed ventilation for an iron-ore mine. The method of sinking the shaft is described, and the costs are stated in mar-hours with a descriptive list of equipment and a statement on the size and use of temporary buildings. Preparation began May 2, 1955, and the shaft was completed at a depth of [680] feet by September 22, 1956. By October 1956, all temporary building and [aft]-sinking equipment had been removed. The total direct-labor cost for the operation, including preparation and dismantling, was 50,700 man-hours, or 30.2 man-hours per foot. Total rock and dirt removed amounted to 17,523 cubic yards (in place), and the shaft lining required 4,635 cubic yards of concrete to form a circular air shaft with an inside diameter of 16 feet.

Jan 1, 1960

By Manuel Gomez

Coking time was investigated as a function of coal properties, carbonization parameters, and the interactions between these variables. The results indicate that coal properties and carbonization conditions interact to influence the coking time, and these interactions may be determined quantitatively. Prediction equations were developed and used to simulate the effects of bulk density, flue temperature, and oven width on coking times for coals having a wide range of properties. The data presented provide additional information on the carbonization process to permit the coke oven operator to maintain closer control of coke production and coke uniformity.

Jan 1, 1968

By Chris D. Winkler

Vanadium-based sulphuric acid catalyst has been utilized to oxidize SO2 to SO3 since the early 1900?s. This versatile product displaced the expensive and easily-poisoned platinum-based catalyst in nearly all applications by the 1930?s. MECS has been manufacturing the vanadium-based catalyst since 1925 and today is the leading supplier in the world of sulphuric acid catalysts in a variety of forms. Currently, MECS has world-wide customer/technical support for the catalyst as well as a dedicated catalyst manufacturing plant in Martinez, California. MECS also has a strong technical and research and development program dedicated to creating new and improved products and services. This paper will describe some of the technical details of vanadium-based sulphuric acid catalysts as well as offering a unique look into how caesium-promoted MECS catalysts can be used in single and double absorption acid plants, and off-gas plants running on irregular gas feeds, to reduce emissions and pre-heater run times. An update on MECS technical services extended for use in characterizing converter performance is also presented.

Jan 1, 2009

By Chris D. Winkler

Vanadium-based sulphuric acid catalyst has been utilized to oxidize SO2 to SO3 since the early 1900?s. This versatile product displaced the expensive and easily-poisoned platinum-based catalyst in nearly all applications by the 1930?s. MECS has been manufacturing the vanadium-based catalyst since 1925 and today is the leading supplier in the world of sulphuric acid catalysts in a variety of forms. Currently, MECS has world-wide customer/technical support for the catalyst as well as a dedicated catalyst manufacturing plant in Martinez, California. MECS also has a strong technical and research and development program dedicated to creating new and improved products and services. This paper will describe some of the technical details of vanadium-based sulphuric acid catalysts as well as offering a unique look into how caesium-promoted MECS catalysts can be used in single and double absorption acid plants, and off-gas plants running on irregular gas feeds, to reduce emissions and pre-heater run times. An update on MECS technical services extended for use in characterizing converter performance is also presented.

Jan 1, 2009

By Tom Gonzales

At San Manuel, AZ, Magma Metals Co. operates an Outokumpu flash furnace, four Peirce-Smith converters and two anode casting wheels that are supported by six anode vessels. Process gasses from the flash furnace and converters are treated in a two-train/ double-contact sulfuric acid plant. The plant captures 98% of the sulfur. A new flash furnace was commissioned in July 1988. It has since processed more than 2.7 Mt (3 million st) of sulfide concentrate without a major rebuild. The company has gained unique experience in the operation of the flash furnace at high oxygen enrichments with low off-gas dust loadings. New procedures have been developed to maintain secondary material generation at equilibrium and for maintaining metallurgical control of operating parameters. Process flow description At Magma&apos;s San Manuel plant, concentrates and other copper-bearing material are blended and conveyed from two separate areas of the plant to three 420 t (465 st) capacity wet charge bins located above the rotary dryer. Flash furnace silica flux is conveyed to a 227-t (250-st) capacity fine flux bin located adjacent to the wet charge bins. The concentrate and flux are blended in controlled amounts and fed into a 168-t/ h (185-stph) gas-fired rotary dryer. The wet charge enters the dryer at 8% moisture and is dried to 0.2% moisture. The dried charge is pneumatically conveyed to a 580-t/h (640-stph) dry charge bin located above the flash furnace. Flash furnace charge is drawn from the bin by two drag conveyors at a concentrate feed rate of 145 t/h (160 stph). The charge is mixed with enriched combustion air and injected into the furnace reaction shaft. In the reaction shaft, the charge is oxidized to form matte, slag and a rich SO, off-gas.

Jan 1, 1992

By Juan Mayta

Dada la situación actual y escenario post COVID-19, es fundamental adoptar estrategias de Gestión Colaborativa e Integrada de Proyectos, este artículo es el resultado de la aplicación de Virtual Design Construction (VDC) y Building Information Modelling (BIM) en la etapa de Diseño de un proyecto de reemplazo de Equipos Críticos en la Parada de una Planta concentradora de Cobre (Cu) para Sociedad Minera El Brocal, operación minera ubicada en Cerro de Pasco, Perú.

Sep 29, 2023