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By R Yong, A McEwan, D G. Miljak, D Milinkovic, A Curtain, P J. Coghill, R Stefulj, B Lovric, G Roberts

The CSIRO has pioneered the development and use of certain classes of magnetic resonance (MR) for mining applications. The MR technique is a radio frequency-based spectroscopy that provides highly quantitative measurement of selected ore minerals. MR has many inherent advantages for bulk sensing in mining applications, including deep sensing penetration into most bulk ores with the use of non-contact sensors that are robust and tolerant of demanding mine conditions. The highly discriminating nature of the technique also provides the very desirable attribute of robust and simple calibration, that can often be performed prior to sensor installation. Rapid sensing (within seconds) at very low grade (few hundred ppm Cu) has been demonstrated, as well as sensing at high tonnage rate. Besides sorting applications, MR may also be applied to preconcentration applications involving very large volume sensing including: (i) haul truck sensing using portal arrangements, where truck destination assignment may be dynamically determined based on the truck grade, (ii) in-pit gantries used for loading trucks that may similarly be equipped with sensors for truck assignment and (iii) deep mine bench sensing, recently progressed through a CRC ORE project, where local bench grade is determined at the few-metre lateral scale and at depth prior to blasting, to aid selective blasting and ore extraction. MR sensor prototypes have been developed for each of these applications and have been tested in laboratory or limited field conditions. To inform the value proposition for truck or bench sensing, initial analysis of truck assignment improvement based on an analysis of in-situ mine bench grade has been performed for a porphyry style deposit. The prototype sensors, preliminary results and future technology development and objectives will be described.

Nov 10, 2020

By R. R. Dorfler

The existing regrind circuit at the Climax Operations uses sodium cyanide and Nokes reagent to reject pyrite, copper, and lead minerals. Laboratory flotation studies were performed using feed to flotation following first-stage regrinding. The effects of conditioning time, pH, and the concentration of depressants such as Nokes reagent and sodium cyanide on the rejection of pyrite, lead, and copper minerals were investigated. The metallurgical results indicate that, in the presence of depressants, the rejection of copper is strongly dependent on the pH. Preliminary mill testing confirmed the finding. The rejection of impurities is also dependent on conditioning time. The recovery of molybdenite is independent of the variables investigated.

Jan 1, 1981

By C. Mattich, A. L. Beyzavi

The Waelz Plant at Taiwan Steel Union Co. Ltd. (TSU) was erected within nine months from September 1, 1998 to May 15, 1999. The nominal capacity of the plant is 50,000 tonnes per year of electric are furnace dust (EAFD). The plant, consisting of material handling, a waelz kiln, a waste gas cleaning system, waelz oxide leaching and waste water treatment, was commissioned within three months from July 1, 1999 until October 12, 1999. The specific problem of the plant is the high chlorine content in the EAFD pellets which is up to 6 %. Lurgi Metallurgie GmbH, Frankfurt, Germany was responsible for the engineering erection and commissioning of the plant.

Jan 1, 2000

By R. R. Falier, W. E. Rice

"PURPOSE OF REPORTThis paper presents the results of a series of tests made by the U. S. Bureau of Mines in cooperation with The Ohio State University Engineering Experiment Station as part of an investigation on the use of fuel in kilns.This report is preliminary and gives only enough of the test data to illustrate results and show the reasons for the successes and failures of the method of firing investigated; fuller details will be included in the final report.PERSONNEL FOR TESTSThe investigation is conducted under supervision of P. Nicholls, supervising fuel engineer, of the United States Bureau of Mines, and G. A. Bole, research professor, of The Ohio State University. These tests were made under direction of W. E. Rice, associate fuel engineer, assisted by R. R. Faller, assistant fuel engineer, of the United States Bureau of Mines; H. C. Harrison, senior research engineer (until October 1, 1930), C. R. Austin, senior research engineer (since October 1, 1930), and H. K. Van Sohoick, junior research engineer, of The Ohio State University. M. J. Rice, field engineer, represented the manufacturer of the stoker.PURPOSE OF INVESTIGATIONThe general aim of the investigation is to develop more economical methods of using fuel in kilns and to improve the over—all efficiency of the process of firing by methods that will produce ware of better quality. One phase of this investigation is the burning of coal on an automatic stoker to gain the advantages of control, constant rate of application of heat, and ability to burn cheaper coal than can be used in the hand—fired furnaces of kilns. It a stoker in to be used it is desirable that the coot of the installation should be low, the control of operation simple, and the distribution of heat in the kiln as good or better than with hand firing. These desiderata were sought in the stoker and furnaces that were used for the tests described herein. The tests were made to determine whether it is feasible to fire a large kiln with a single stoker, whether the use of a single furnace simplifies control, and whether the admission of all the hot gam at the center of the kiln will give symmetrical distribution of heat."

Aug 1, 1931

Each year the South African Institute of Mining and Metallurgy offers a prize (or prizes should the entries warrant it) of up to RlOO for the best paper or dissertation on a topic appropriate to the interests of the Institute. The competition is open to all Student Members of the Institute. A Student Member who is in fulltime study at a university may submit the dissertation or thesis he has to write in part fulfilment of his university degree, provided that it is presented in a manner and on a topic suitable for publication in the journal. Entries for 1976 should reach the Institute by 31st December, 1976.

Jan 10, 1976

By Robert Lewis

Some recent experiments in the use of compressed air for rock drills at higher than usual pressures, up to 150 lb. per sq. in., emphasize the importance of maintaining the compressed-air system in the best condition if the greatest possible over-all efficiency is to be secured. No claim of high over-all efficiency can be made for the compressed-air system of braking that is used on railroad trains, yet the air brake works effectively. Compressed air is not used efficiently in the rock drill, but no other type of machine drilling is yet a serious competitor of the air-driven rock drill.

Jan 1, 1930

By H. R. Coles, S. P. Chong

Test work conducted in the 6.4 and 10.5 m (21 and 34 ft) Aerofall mills at the Iron Ore Co. of Canada Carol project showed that conventionally used "deflector" type liners, which form the basic principle of Aerofall Mill grinding, did not necessarily provide the best grinding performance. A new design, using low profile liners incorporating radial ribs of proper height, actually improved the mill throughput 9-20% without sacrificing grinding efficiency. In addition, the new design reduced liner weight and scrap losses, resulting in a 25% reduction in liner consumption. It provided better protection to the mill shell and reduced the overall maintenance cost for the mills.

Jan 1, 1984

By Pradip

The selection, testing, and commercial utilization of flotation reagents is best carried out in stages through microflotation tests on pure minerals and their synthetic mixtures followed by bench-scale batch flotation tests on the ore. A systematic approach to quantitatively evaluate different reagents, in particular, through the analysis of batch flotation data, has been presented in this paper. It is recommended that the reagents are compared both in terms of their performance with respect to the recovery-time as well as the recovery-grade plots. While the former describes the kinetic aspects of reagent interaction, the latter is a measure of its selectivity for a particular separation problem.

Jan 1, 1987

By X Yu, Y Shen

The iron ore products should be assessed in terms of in-furnace behaviour and overall furnace performance, their operation should also be optimised under industry-scale blast furnace (BF) conditions, in order to be sustainable and competitive, especially in the context of decarbonisation efforts in ironmaking. While lab and pilot-scale experiments can provide useful kinetics, they are expensive and risky and cannot replicate industry-scale blast furnace conditions for proper assessment and optimisation. In this paper, we review our recent progress at Shen Lab of UNSW in using state-of-the-art Computational Fluid Dynamics (CFD) models to assess iron ore products and examine the effects of their operations on BF behaviour in basic terms, including in-furnace phenomena (flow field, temperature field, species distribution fields etc) and overall BF performance (coke rate, reduction efficiency and top gas temperature etc). We have developed state-of-the-edge CFD models for different purposes, ranging from the static-state BF model featuring unique layered burden structures for offline assessment and optimisation knowledge building-up for iron ore products, to the transient-state BF model for online assessment and optimisation of iron ore productions by describing the transient behaviours of iron ore productions under industry-scale conditions. First, we have studied several iron ore products including the iron ore products used in the present BFs and emerging iron ore products like carbon composite briquette and iron-coke. Second, several iron ore operations are studied including optimisation of conventional burden operations like oxygen enrichment, batch weight tuning and new operations like coke central charging and hydrogen injection in BFs. Third, some time-sensitive operations are also investigated including the use of wet burden materials and the drop in blast temperature on BF performance. These CFD models offer cost-effective research tools for understanding the effect of iron ore products on BF performance and serve as a reliable marketing tool for existing and emerging iron ore products under a wide range of BF conditions.

Sep 18, 2023

By J. L. Holman

The Bureau of Mines, at its Rolla Metallurgy Research Center, has devised methods for separating and reusing the major portion of waste plastics discarded in urban and industrial refuse. Waste plastic concentrates from a local collection drive, recycling center collections, urban refuse pilot plants, and the secondary metals industry were separated into three major thermoplastic families--polyolefins, styrenes, and vinyls--based on differences in density using a Bureau-designed sink-float-elutriation hydraulic separator. Other separation methods and systems such as air classification, jigging, liquid media, screening, and electrostatics were studied. Vinyl plastics contain up to 50 percent HC1. It was found that over 90 percent of the HC1 in vinyls can be recovered as usable hydrochloric acid by pyrolysis at 350° C. The remaining pyrolysis products which had heats of combustion in excess of 12,000 Btu/lb, could become valuable as a future source of energy. A characterization study conducted on eight chopped wire insulation wastes from secondary copper and aluminum processors showed that most wastes contained 2 to 7 percent residual metal and large percentages of vinyl. The residual metal content of some of these wastes was lowered to 0.1 percent and the vinyl portion segregated using various separation techniques. The research also suggests ways in which reclaimed thermoplastics may be fabricated into useful products.

Jan 1, 1974

HONORARY Membership in the Institute is limited to twenty and the roster is now only fifteen, so Dr. Reynders becomes a member of a select circle. All of his life, following graduation from Rensselaer Polytechnic Institute in 1886 at the age of twenty, lie has been connected with the steel industry. For about thirty years he stayed with the same company, the Pennsylvania Steel Co., until it was acquired by the Bethlehem Steel Corp., in 1916. For many years he had been vice-president and general manager. Before he attained that position, Dr. Reynders organized and remained in charge of the bridge-building department of the company, and during his professional life he has directed the construction of many

Jan 1, 1938

By Clark Woodland, William E. Stanley

Mining companies have been required to enter a "new era of management" in the 1980's as they strive to become more efficient in an increasingly competitive market place. One response for many companies has been to modify their mine accounting systems to make them more effective for cost control and decision-making. This paper discusses some of the major issues in developing and implementing a standard costing system as part of improved management reporting and cost control procedures. It describes the key features and benefits of a computerized standard costing system with particular emphasis on budget-setting and variance analysis. It also identifies important factors to be considered in order to achieve successful project planning and Implementation.

Jan 1, 1987

Mining is a global industry. The conference is a good example of this, as itÆs jointly organised by professional associations from Canada, Australia and South Africa, and has attracted speakers and delegates from around the world. I commend the organisers for their initiative. I am pleased to be asked to participate in this panel û although I would hasten to add I see myself as perhaps an informed observer rather than an expert. It wonÆt be news to most in this room that AustraliaÆs mining sector is booming. As one of the most productive and diversified mineral regions in the world, this activity is also something that has not escaped the attention of CanadaÆs largest mining companies! This means that I follow what is happening in the industry and more specifically what might be occurring here. Two-way investment between Canada and Australia stood at $9.8 billion in 2005 with Canada as the seventh largest overall investor in Australia with $8.22 billion in investments. The majority of this investment is by Canadian minerals and metals companies. In recognition of the importance of Canadian investment in this sector in Australia, I maintain close contact with our companies. By way of example, in the past two months I spent a week in Western Australia visiting Perth and meeting with companies for example, like Teck Cominco and LionOre as well as seeing various Barrick Gold operations in Kalgoorlie. I attended the opening of AlcanÆs new Asia Pacific Headquarters in Brisbane in August and just two weeks ago was in Cowal, NSW for the opening of BarrickÆs new mine there. Having met with BHP Billiton in Vancouver, IÆm equally aware of active Australian mining interests in Canada. This is not designed to indicate how active I am but rather to demonstrate the dynamism in the mining industry and the diversity of Canadian mining interests in this country and Australian interests in Canada.

Jan 1, 2006

By A. L. Barnes, A. M. Rowe

A heat transfer study was made of hot gas injection into oil shale through wells interconnected by vertical fractures. This analysis involved the simultaneous numerical solution of a nonlinear, second-order partial differential equation that describes two-dimensional conduction heat transfer in oil shale and a nonlinear first-order partial differential equation that describes convection heat transfer in the fractures. Three nonlinear, temperature-dependent coefficients were used in this work; they are thermal conductivity, thermal capacity and retorting endothermic heat losses of oil shale. Vertical fractures were considered to be of finite height. Although vertical conduction heat transfer was not considered, an estimate of the error resulting from this limitation was made. The effects of injected gas temperature, injection rate, system geometry, cyclic injection and time upon retorting efficiency were investigated. Results from this study show that the rate of retorting oil shale is a direct function of both injection temperature and rate, and the theoretical producing air-oil ratio:(AOR) is an inverse function of temperature. Retorting rates are constant until "breakthrough" of the 700 F isotherm at the producing well, assuming constant injection parameters. Retorting rates for bounded systems are higher than the analogous unbounded systems and likewise AOR's are less. The use of an alternating injection-soak routine with high injection rates is less efficient than continuous injection at lower rates. These results indicate that injection temperatures on the order of 2000F or greater may give theoretical AOR's in the economic range. INTRODUCTION Over half of the known oil shale reserves are located in the U.S., and most of them lie in the Piceance Creek basin of Western Colorado. The Colorado oil shale outcrops on the edges of the Piceance Creek Basin. At the outcrops the shale beds are relatively thin, from 25 to 50 ft thick. In the center of the basin the oil shale is as great as 2,000 ft thick and is covered with 1,000 ft of overburden. It has been estimated that there are over 1,000 billion bbl of oil in shales having an oil content over 15 gal/ton in this basin. Oil shale does not contain free oil but an organic matter called kerogen. Kerogen yields petroleum hydrocarbons by destructive distillation. It must be heated to approximately 700F, at which temperature it decomposes into shale oil, gases and coke. The U.S. Bureau of Mines and, more recently, oil companies have conducted considerable research on surface retorting methods to economically recover oil from this shale. Another approach to exploit the oil shale deposits, in particular that portion having 1,000 ft of overburden, is to retort the oil shale in place and produce the liquid and gaseous hydrocarbons through wells drilled into the shale. Some research has been done on this approach.l,2 There are several variations to the in situ retorting approach. These variations fall into one of two groups, depending upon the geometry of the system: (1) retorting in a highly fractured or broken up matrix; (2) retorting from single fractures between production and injection wells. The latter is the group studied. Several investigators,3-6 using various assumptions, have studied flow of heat through horizontal systems. The objective of this work was to make a heat transfer study of in situ retorting oil shale by hot gas injection through wells interconnected by single vertical fractures of finite height. The oil shale thermal conductivity, thermal capacity and retorting endothermic heat losses were considered to be functions of temperature. A knowledge of the

Jan 1, 1969

By A. Johnson

When are SMART transmitters the smartest choice? To answer this question requires a closer look at SMART transmitter technology. It is necessary to understand this technology in order to recognize how it can best be utilized to give the greatest value for the application. And, once the decision to buy transmitters has been made, it becomes a question of whose SMART transmitter to buy. For, although the under-lying technology is similar, the differences that exist in how the technology has been implemented can make a dramatic difference in the end result. What prudent users of SMART technology do is to analyze their needs by application before making their buying decision.

Jan 1, 1988

Mineral deposits of the central New Guinea region (Gunung Bijih, Ok Tedi, Mount Kare, Porgera, Frieda River) and of southeastern New Guinea (Wau-Edie Creek, Wafi, Hamata, Hidden Valley, Tolukuma, Misima) are associated with hot, forceful intrusions of magma of mantle origin that penetrated thick Precambrian and Palaeozoic continental crust. The interaction of high- temperature melt with continental crust, and the differentiation of melt while in transit through thick crust, may be factors in generating ore. Mineralised intrusives in central New Guinea are a result of Neogene- Quaternary magmatism and were emplaced in a foreland thrust belt environment, a setting similar to the (mineralised) Laramide intrusions of southwestern USA. In both cases, central New Guinea and the Laramide, magmatism is not obviously subduction- related. Mineralised intrusives in south- eastern New Guinea (Wau-Edie Creek, etc.), also, are in a thrust belt setting, and are not obviously subduction-related. The association of. gold in southeastern New Guinea with a second (Pliocene) phase of igneous activity, rather than with earlier (Miocene) activity suggests that re-working by successive intrusions may be a factor in localising ore. This is seen, also, in the Bismarck-Solomon islands region where the richer deposits are associated with later (Pliocene) intrusives rather than with earlier (Eocene-Oligocene) intrusives. Unlike the mainland mineral deposits, those of the Bismarck-Solomon islands are clearly subduction-related.

Jan 1, 1991

By Wenxue Chen

This paper presents a new type of bolt with full thread and uniform strength, and fabricated with a Glass Fiber Reinforced Polymer (GFRP) bolt-making machine designed by the authors. The mechanical performance of the new bolt is assessed with strength tests conducted with the bolt in acid, alkaline and saline water conditions, with increasing concentration. The purpose is to test the new GFRP bolt?s mechanical performance in harsh conditions, especially metal mines with acid or alkaline environments. Comparison of the color, weight, size and antistatic ability of the GFRP bolt before and after it is immersion in solution is presented. Changes in tensile and shear strength, torsion, and anchoring force were evaluated in the laboratory. The results show that the mechanical properties of the GFRP bolt are more sensitive in alkaline than in acid and saline water. However, the loss ratio of mechanical properties of the GFRP bolt is very small according to the results of tensile and shear strength, torsion and anchoring force. The new bolt can be useful for applications in acid or other harsh mines.

Aug 1, 2013

By Eleanor Abshire

[THE INCREASING use of hafnium as a vital component in atomic power reactors has brought this metal into recent prominence. A literature survey was made and this bibliography was compiled to provide research and production groups with a ready source of reference to this important metal anti its compounds. This service is rendered by the Zirconium Information Center, which is sponsored by the Department of the Navy, Bureau of Ships, and the F .S. Department of the Interior, Bureau of Mines, tit the Bureau's Northwest Electrodevelopment Experiment Station, Albany, Oreg. The following reference sources have been reviewed for this compilation : Chemical Abstracts; Industrial Arts Index; Crerar Metals Abstracts; Nuclear Sciences Abstracts; Bureau of Mine; Information Cicular 7771, Bibliography of Zirconium; anal Bureau of Mint' Information Circular 7830, Bibliography of Zirconium, suppllement to Information Circular 7771.]

Jan 1, 1960

By Smith, George Otis

ENGINEERING is in essence quantitative, and the engineer must deal with exact figures when he plans and, constructs. Engineering truths are not best expressed by adjectives, yet my wish, today, is not to attempt a quantitative measure of the dominant position of the mineral industry of the United States in the existing scheme of material things, but rather to seek a clualitative appraisal of what mining and metallurgical engineers are doing to promote and make secure our , national progress. Statistics help when we wish to gage material prosperity, but they fail when we desire to determine what share the engineers have in adding to the happiness and welfare of our people

Jan 1, 1928

By Edmund S. Leaver, Jesse A. Woolf

"The Baboquivari mining district is about 60 miles southwest of Tucson, Ariz., the present railroad shipping point. The values are silver and gold. The silver is largely associated with the black oxides of manganese. The ore is highly oxidized, and careful panning shows only a very small amount of pyrite. Our sample analyzed as follows:A flotation mill has been installed in the district, but it does not concentrate the precious metals satisfactorily. Our best laboratory flotation results were obtained by grinding to pass 65-mesh and floating with Xanthate or standard flotation oils plus sodium sulphide and polysulphide. This sulphidizing method gave a concentration of 32 per cent of the silver and 80 per cent of the gold, which about equals plant practice.We do not know of an instance where the oxidized forms of manganese have been concentrated satisfactorily by flotation.Plain cyanide on the original ore extracts practically all of the gold but only one-third of the silver. A preliminary deoxidizing roast, using producer gas or powdered coal, gives a calcine from which cyanide dissolves about 90 per cent of the gold and 75 per cent of the silver. This method of treatment, known as the Clevenger-Caron process, is described in Bureau of Mines Bulletin 226.Preliminary treatment with sulphur dioxide by burning pyrite or sulphur and passing this gas into the pulp until all of the contained manganese is dissolved or changed in form best prepares the ore for cyanidation. The acid consumption will vary with the percentage of manganese and other soluble constituents. Neither gold or silver is dissolved by this acid treatment. The washed residue gives maximum cyanide dissolution of the gold and silver with minimum loss of cyanide,"

May 1, 1928