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By Geoffrey Brooks, Ben M. Ekman, M. Akbar Rhamdhani

"Concentrated solar collectors including solar simulators have been studied to concentrate solar radiation to flux levels capable of reaching temperatures of 3000K. Currently, there are no industrial scale solar reactors used for material processing and only small research units have been tried. Various laboratory scale solar reactor designs are reviewed including their operating temperature and heat transfer efficiency. Solar reactor designs can be classed into directly or indirectly irradiated and single or double cavity construction. Thermal efficiencies of up to 40% have been achieved in experimental units while operating at 1500K. Problems are encountered that relate to the transfer of high heat flux. Hybrid reactor system should be considered in the future to overcome some of the practical issues associated with solar thermal reactors.I. INTRODUCTIONIn the high temperature processing of materials, such as the production of metals, cement, refractory or glass, the reactions are typically performed in the range of 500° to 2000°C. Metals are produced from minerals, which maybe oxides, sulphides, chlorides or silicates, and to recover the metals, these compounds have to undergo chemical reaction to liberate the metal. The thermodynamic stability of these compounds found in minerals necessitates the use of high temperatures to break down the bonds between the metals and other elements. Normally, the raw metals produced from smelting require refining, which is often carried out in the molten state. As new energy sources have been established, new furnace designs have evolved to incorporate the latest technology. Although solar energy has existed longer than all the current energy sources, it has not yet been incorporated into any industrial smelting; refining or melting processes. The solar radiation reaching the earth’s atmosphere, called the “Solar Constant” (SC), is defined as the rate at which solar energy is incident on a surface normal to the sun’s rays at the outer edge of the atmosphere when the earth is at its mean distance from the sun. The currently accepted value is 1367 W/m2 [1]. The earth intercepts only a small amount of this and 30% is reflected back into space, 47% is converted to low-temperature heat and reradiated into space and 23% powers the evaporative and precipitation cycle of the biosphere [2]. As a result, the solar energy reaching the earth’s surface is weakened considerably to about 1000 W/m2 or one sun, on a clear day and much lower on cloudy or smoggy days [3]. The thermodynamic limit for solar concentration is determined from the inverse square law [4] by the factor sin2? = 46,764 sun’s [5] where ? is the angular size of the sun and equals 0.0093 radians [7]. This would produce a steady state temperature equal to that of the sun’s surface of approximately 5800oC. In practice however much lower concentrations are achieved due to geometrical and optical imperfections, shading effects and tracking inaccuracies. Optical configurations based on parabolic-shaped mirrors are commercially available for large-scale collection and concentration of solar energy for the generation of electrical power. The most common configurations used for concentration of the sun’s energy in solar thermal applications are parabolic troughs, solar towers and parabolic dishes [8,9]."

Jan 1, 2014

By M. J. Ferrante

Relative enthalpies of V20S from 298.15 to 1,101.0 K were measured at the Bureau of Mines to provide data needed for the advancement of min-eral technology. Enthalpies were measured with a copper-block calorimeter. A sharp melting point was found at 951 K, with [~~ = 15.690 kcal/ mol ] for the standard enthalpy of melting. Tabulated values are given at selected temperature increments between 298.15 and 1,500 K for the standard relative enthalpy [(HO -H~98),] heat capacity (CpO), entropy (SO), and Gibbs energy function [-(Go -H298)/T]. Standard relative enthal-pies are also given in equation form and combined with data from the literature to derive values of standard enthalpies of formation and Gibbs energies of formation.

Jan 1, 1986

By H. B. Hill

Virtually from the date of its discovery in December 1928 the Oklahoma City oil and gas field, Oklahoma County, Okla., has attracted national and international attention. The history of the field has been associated closely with rules and regulations pertaining to production control and proration practices. Early development was rapid, and Oklahoma City soon attained the distinction of being the first major field in which the producing wells were over a mile in depth. Before the structural features of the reservoir had been disclosed every outpost well was considered a "wildcat", so complex appeared the underground geology. The wells not only were deep and the reservoir pressures high, but the production from the early wells was a high A.P.I. gravity oil, accompanied by large volumes of gas. Several "blow-outs" and fired occurred during the early development, and the close proximity of these now unusual events to a large city gave the field much publicity, both local and national. Later, when its production threatened to demoralize the market for oil and its products, the Oklahoma. City field again attracted wide publicity. The then little understood geology of the underground reservoir and the diversity of ownership of the land overlying the producing structure made orderly development and production difficult to enforce. Proration was enforced with difficulty, and the rate of production from the field continued to increase until, on August 4, 1931, martial law was declared in all prorated fields of the State, and most of the wells in the Oklahoma City field wore shut in. On October 9, 1931, permission was granted to reopen and produce the wells in the Oklahoma City field. The order permitting production of the wells provided that during the period beginning October 10 and extending to October 20, 1931, all wells in the field that had not produced more oil than specified under the earlier proration orders and that had been shut in for the required 65-day period were permitted to produce 5 percent of their last potential during that 10-day period.

Jan 1, 1936

By Rollie E. Dutton, David A. Stubbs

"A sensor has been developed and tested that is capable of emitting and receiving ultrasonic energy at temperatures exceeding 900°C and pressures above 150 MPa. The sensor works with standard ultrasonic pulser-receivers and has demonstrated the capability of measuring workpiece deformation during hot isostatic pressing (HIP). Details of the sensor design, performance, and coupling of the ultrasound to the workpiece are described. Ultrasonic data acquired by the sensor, in situ, during HIP runs and at elevated temperatures in air are presented.INTRODUCTIONHigh temperature structural components, such as structural castings for jet engines, nickel-base superalloy turbine blades, and ceramic and metal matrix composites made from powders are often densified by hot isostatic pressing (HIP). For powder consolidification, the HIP process involves sealing the powder (and reinforcing fibers for composites) within an evacuated ""Can"" made of a material that softens at high temperatures. A hydrostatic pressure is then applied by pressurizing the inside of the HIP vessel with argon gas (up to 140 MPa). The hydrostatic pressure densities the powder through the elimination of the porosity between the powder particles.This paper presents details of the development and preliminary testing of an ultrasonic displacement sensor that can be used to monitor materials processing, in situ, at temperatures and pressures significantly higher than current ultrasonic displacement sensors. The target processing environment for this sensor is that typically found in a hot isostatic pressure (HIP) vessel, i.e., temperatures exceeding 1000°C and pressures above 138 MP a."

Jan 1, 1997

By W. C. Holliman

This report describes apparatus and procedure used for determining the vapor pressure of aviation gasoline in surveys of commercial aviation-gasoline characteristics made by the Bureau of Mines in cooperation with the Coordinating Fuel and Equipment Committee of the Coordinating Research Council, Inc. (CFR-CRC). The method is a modification of the Reid method, in which a mercury manor is substituted for the Bourdon-type gage of the Reid method. The method was used in earlier surveys made by the National Bureau of Standards in cooperation with the CFR-CRC, and was used in the Bureau of Mines surveys at the request of the cooperating organizations. It is designed for special research problems? particularly in vapor-lock studies, which require a precision greater than obtainable by the Reid vapor pressure method. A repeatability of + 0.01 p.s.i. average deviation from the mean may be obtained by method.

Jan 1, 1950

By E. Van Den Neste

A concise historical review is given of the Overpelt plant and the general principles of zinc hydrometallurgy are briefly outlined, together with a description of the new electrolytic zinc plant ore roasting process and, more particularly, the original Overpelt roasting process. A detailed description of the flowsheet of the zinc electrowinning plant, .with an annual capacity of 100,000 t, successfully put into operation in May 1974, is given. The treatment of the residues is performed following the goethite process ; the purification is continuous in two steps; the tank house is equipped with cells containing jumbo cathodes; the handling and stripping of the cathodes is fully mechanized. Concluding the description, some metallurgical and other features of the project are explained in detail.

Jan 1, 1977

By Charles H. Atkinson, Robert T. Johansen

Tremendous volumes of petroleum ( crude oil and natural gas ) at present cannot be recovered economically . The feasibility of using nuclear explosions for production stimulation therefore has been investigated . Data from underground nuclear tests conducted by the Atomic Energy Commission were reviewed , and the physical effects were evaluated for stimulating petroleum production . Calculations of the effect on ultimate recovery of increasing reservoir temperature with nuclear explosives showed disappointingly small increases . Production increases caused by fracturing of massive low- permeability reservoirs appear technically and economically promising . Petroleum reservoirs that might be converted from submarginal to commercial production are being located and evaluated as to potential reserves and as a location for a field test .

Jan 1, 1964

By J Isles, S King, A Valenza, R Lawolo, J Evert

PT Nusa Halmahera Minerals (PT NHM) is an Indonesian joint venture company owned by a subsidiary of Newcrest Mining Limited (75 per cent) and PT Aneka Tambang (Persero) (25 per cent). PT NHM operates two underground gold mines, Kencana and Toguraci at the Gosowong mine site in North Halmahera District, North Maluku Province, Indonesia.The Toguraci underground mine development commenced in 2011 with ore production commencing in 2012. Water temperatures ranging from 50°C to 80°C were encountered in the Toguraci open pit associated with the structures containing the gold bearing veins and are believed to be fed from a relic volcanic system one to two kilometres below the mine. Underground development and production has continued to intersect these structures with the result that an integrated programme of geological, hydrogeological modelling and operational project work has been required to dewater the mine ahead of the descending stoping fronts.This paper will detail these programmes.CITATION:Lawolo, R, Isles, J, Evert, J, Valenza, A and King, S, 2017. Hot water management at PT Nusa Halmahera Minerals’ Toguraci Mine, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 191–198 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By Thomas M. Nasiatka

This report briefly describes the present state of the art and the technological highlights of tunneling from its inception to the present. The discussion is concerned primarily with tunnels driven through relatively competent rock for mine development and various civil purposes. In addition to pinpointing the major technological breakthroughs in tunneling, this report indicates their general effect on the speed of tunneling. The tunneling speeds are based upon data from approximately 80 tunnels listed in the appendix. These data include length; cross section shape and dimension; type of rock; tunneling method; method of breaking, loading, and transporting the rock; average linear progress rate; and cost in values during the period of construction. Most of the tunnels described have diameters of 15 to 30 feet.

Jan 1, 1968

By H. A. Wheeler

IT may surprise some of our members to learn, among the industries based on the mineral resources of the United States that of clay now ranks third, being exceeded in value of product only by pig-iron and coal. The present annual value of clay-products exceeds the value of the outputs of gold and silver, and also exceeds the combined values of copper, lead, zinc, aluminum, mercury, antimony and nickel. These facts are shown in Table I. which gives the statistics for the year 1902

Jan 1, 1905

By L. Keith Hudson

The purpose of this study is to provide data that demonstrates that the Alcoa flash calciner design can be used for the decomposition of AlCl3?6H2O to A1203. Heat and material valance data for calcination provides data on the partial pressure of HCl in the off-gases. Experimentally determined data for the HCl partial pressure, over solutions expected in producing alumina from clay by the hydrochloric acid process, show that HCl can be absorbed from the off-gases into process solutions to effect crystallization of AlCl3?6H2O.

Jan 1, 1979

By M. E. Kundick, W. E. Dieter, L. Cohen

The major details of design and maintenance of a seamless stainless steel fume hood system , developed by the Bureau of Mines , are described and illustrated . Operating and housekeeping routines are outlined .

Jan 1, 1964

By E. Neumann

With fuel costs unstable but escalating, solid fuels are playing an increasingly larger part in industrial concerns. Coal, petroleum coke and wood are examined from a burner system design viewpoint and from operational experience in kilns, hot gas generators, etc. The burner of today must also handle multi-fuel tasks and allow immediate, painless switching from one fuel to the next as well as the simultaneous burning of two or mope fuels. The paper discusses the principle of burning alternate pulverized fuels as well as the practice both in the United States and around the world.

Jan 1, 1983

By H. Herbert Hughes

Iceland spar is a variety of calcite ( calcium carbonate ) characterized by its purity , transparency , and perfection of crystalline structure . It takes its name from the country in which it was discovered . The actual demand for it is small , but the supplies of high - grade optical spar are so meager that the search for it has become international in its scope . Iceland spar is a scientific necessity , for without it research precision and technology would be hampered considerably . The earliest students of mineralogy were familiar with calcite , but the transparent variety was not discovered until early in the seventeenth century , when crystals of it were found in the bed of a stream in Iceland . It received little attention until 1669 , when Erasmus Bartholinus first recognized its powers of double refraction . The results of his investigation were published in a book , " Experimenta Crystalli Islandici , " which appeared in 1670. The law governing the action of the rerracted rays was discovered by Christian Huygens eight years later . The polarization of light rays in passing through Iceland spar was discovered in 1809 by Etienne Louis Malus , a French physicist , who published a paper describing the phenomenon . His work was closely followed by that of William Nicol , who in 1828 designed the Nicol prism which is still used as the source of polarized light in most optical instruments .

Jul 1, 1931

By F. R. Archibald

Introduction It is the purpose of this paper to review the subject of roasting as preparation of refractory gold ores and concentrates for cyanidation, with particular reference to operations at the mill of Beattie Gold Mines (Que.), Ltd., Duparquet, Quebec. Two earlier papers relating to the Beattie roasting operations are cited as background to the ? present discussion, and more general reference is made to other publications relating? to geology and metallurgy at Beattie. The Beattie roasting plant was built in 1937 as an addition to the existing flotation and cyanidation plant to permit complete processing of the ore at the mine property. Previously, the flotation concentrate had been cyanided, yielding 70 per cent of the gold values, followed by re-flotation of a concentrate from the cyanide residue. This re-floated residue was shipped to a smelter for recovery of gold values unavailable from direct cyanidation. The roasting plant itself is of interest through application in its design of multiple-hearth roasters and a Cottrell plant for separate recovery of dust and arsenic. In the laboratory and plant studies that accompanied development of the plant into a dependable and efficient working unit have been found principles and ideas applicable to other roasting 'problems. Before enlarging on these aspects relating particularly to the Beattie problems and plant, brief consideration is given to roasting in general.

Jan 1, 1949

By H Arvidson, Rondinelli Sousa, Nic Pollock, Cesar Carrasco, Boz Elloy

Global public mineral reporting codes have driven strong governance of public disclosures of minerals information. Recently, we have seen an increase in disclosure of information related to Environmental, Social and Governance (ESG) issues, and governance of ESG information in mining companies has arguably reached a similar level of governance and diligence afforded mineral reporting. We define Resource Governance as the conjunction of environmental, social and minerals governance. A modern systems approach to Resource Governance, which combines mineral and ESG information, would provide not only reporting and governance capability, but also has the potential to sense/respond, predict, and manage ESG risks.

Feb 1, 2024

By Tim Gitzel

Thank you for your introduction, and thank you to the CIM for inviting me to make a presentation to you today. This is my first opportunity to report to you on the status of the Canadian uranium industry and I am pleased to tell you that the industry is in good shape, and well positioned for the future. As you will no doubt be aware, Saskatchewan benefits from the world?s largest known highgrade deposits of uranium as well as from a high level of provincial, public and northern community support. It is within this unique combination of geology and community that our industry operates. Uranium markets have been extremely competitive for a number of years for several reasons. First, deregulation in the nuclear electric power industry has tended to encourage fuel buyers to use up their large inventories built up at a time when rapidly increasing demand was anticipated. Second, alternate sources from surplus commercial stocks, military materials and reprocessed fuel have presented a major additional source of uranium supply. Today, these secondary supplies are meeting about half of uranium reactor feed requirements. Canada (that is, Saskatchewan) is the world?s largest ?natural? uranium producer with about a third of the global production. Saskatchewan?s mines produced more than 30 million pounds of yellowcake in 2002. Despite low prices, steady demand for uranium will continue. In fact, an increase in world uranium production in 2002 helped feed a more than 3 per cent increase in reactor fuel demand. Low cost production is important for surviving low market prices, but investments are based on longer-term strategies rather than simply responding to market cycles. Cost is not the only issue. In these times of increasing regulatory and public scrutiny we must continue to earn the trust of our stakeholders by adopting the highest standards and staying on the leading edge of technical, social and environmental developments. Managing these issues is as important as traditional concerns of ore grade and cost of production. The last two decades of the 20th century saw the Province of Saskatchewan rise to prominence as the leader in uranium production from facilities, which were at the time deemed world class. These facilities are now either at - or nearing - the end of their production years. We are now bringing on new facilities that will position Saskatchewan to remain the world leader in uranium production for many years to come.

May 1, 2003

By E. V. Manlapig, M. C. Harris

"The complexity of the flotation process has made the identification of an appropriate model structure, for use in the prediction of flotation circuit performance, far from obvious. Work performed under the auspices of the AMIRA P9 flotation program has indicated that the metallurgical performance achieved from a flotation cell arises from the interaction of two essentially independent property classes, namely the cell operating conditions and the properties of the cell feed stream. These observations have led to the development of a model structure that associates a constant set of flotation parameters to the streams of the circuit, which are transformed into a flotation response depending on the operating conditions within the flotation cell.A variety of alternative model structures exist within the literature which do not make this distinction between cell and stream flotation properties, and many of these models are in widespread use for flotation optimisation and design studies, both in industry and academia.In this paper, data collected from an industrial flotation circuit is used to derive the parameters associated with two different types of flotation models. Simulations performed using these models demonstrate the need to differentiate between cell and feed properties. A model that does not differentiate between these two properties fails to successfully predict the metallurgical performance of a flotation circuit after a disturbance."

Jan 1, 2003

By W. G. Davenport

This chapter shows how flash furnace industrial oxygen and oil requirements are affected by different: (a) product temperatures (b) conductive, convective and radiative heat losses (c) electrical energy inputs (d) hydrocarbon fuels. The calculations of the chapter are all for production of 65% Cu matte from pure CuFeS2 concentrate. Blast temperature is? 298 K throughout.

Jan 1, 2001

My purpose here today is to introduce an element of democracy into this seminar. In my experience, the mines of Australia can be divided into two categories; those that pay and those that don't. As far as I can ascertain, every other paper being delivered at this seminar concerns mines which come into the first category, or at any rate are close enough to it for the promoters to be able to afford an expert's valuation.

Jan 1, 1989