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By Christopher W. Corti

A major aim of the GOLD 2003 conference, is to promote new gold related science and technology with a view to developing new useful industrial applications for gold. Current industrial uses have provided a steady annual industrial demand for gold of around 350-400 tonnes in recent years, the bulk of which is centred on electronics applications, with dental uses constituting the second largest application. However, there is good reason to believe that whilst gold will continue to play a major role in these sectors in the future, substantial growth of demand is not anticipated. Increased industrial demand for gold is only likely to come through the emergence of new applications, probably most significantly in five broad market sectors: ? Pollution and emission control technologies, including fuel cells. ? New uses for gold in advanced electronics, electrical systems and devices. ? Chemical processing of a range of bulk and speciality chemicals, using gold based catalysts ? Advanced coatings exploiting the novel properties of gold, particularly in nanoparticulate form. ? New biomedical uses for gold including medical treatments, drugs, implants, sensors and devices. There is cause for optimism that many new applications for gold could emerge in these sectors over the next decade and that this will lead to a substantial growth in demand for gold. It is clear that many of these new opportunities will be based on a chemical approach to synthesis of useful products rather than what has historically been a materials or mechanical approach. To turn this expectation into reality requires sustained support of R & D and a determination to exploit this new science and technology into viable commercial applications.

Oct 1, 2003

By Tilden Cummings

The extractive mineral industries share a number of common characteristics and basic problems which are completely different from those associated with manufacturing and mercantile operations. These industries now supply about 95% of the inanimate energy consumed in this country, and share with agriculture in providing virtually all of our basic raw materials. Mineral producers, like farmers, are subject to the economic hazards of fluctuating markets and prices. Unlike farmers, however, they cannot renew the productivity of the earth, but must seek continually for new sources of supply. The necessity for exploration and development of new reserves, to replace those used up by production, introduces additional factors of economic risk. These operations require the expenditure of large amounts of capital, often well in advance of any assurance of profitability. Commercial banks that understand these special problems can provide a variety of constructive financial services to the mineral industries. The history of cooperation between banks and mining enterprises has yet to be written, but there is every indication that it would encompass a period of hundreds of years. Records refer to depository and lending services by the early European private bankers involving precious metals and jewels. Many of the exploratory voyages to the Far East and the New World were organized with the financial backing of wealthy syndicates, some of which also provided banking services, in the hope of finding new sources of gold and other precious minerals. In the United States many large banks are closely identified with the development of some of the larger mineral deposits such as the Mesabi Range and the gold fields of California.

Jan 5, 1965

By Robert J. Storms, David J. Malone, Thomas E. Crandall

Corrosion and abrasion have been present in hydrometallurgical processes for many years. Ceramic lining materials have been used in several applications to protect process vessels from the corrosive and abrasive effects of a wide range of ore slurry processes. This paper reviews the history of ceramic lining systems utilized in hydrometallurgical vessels, the commercial benefits associated with their use, and additional areas of opportunity for the Mining Industry.

Jan 1, 1995

By K. Tempel

In December of 1999, Newmont Mining Corporation’s Eastern Nevada Operations commissioned its commercial biooxidation facility. The commercial biooxidation facility is a refractory gold whole ore heap process that uses bacteria to assist with the oxidation of sulfide minerals thus liberating occluded gold for further processing by cyanide for gold extraction. Before the commercial biooxidation facility was started, a decade of research went in to developing this state-of-the-art process. During final design and construction of the commercial facility a decline in gold price necessitated cost saving and project scope changes. As a result, the biooxidation process experienced many challenges. Some of the more significant challenges include poor heap permeability due to haul truck stacking, unhealthy bacteria population due to a lack of solution aeration, and insufficient biooxidation time because of limited pad space and high carbonate content in the ore. This paper discusses the many challenges encountered and addressed during the first 2-3 years of commercial biooxidation operation.

Jan 1, 2003

By P. Somasundaran, D. R. Nagaraj

This study initiated to explore the potential of commercial chelating extractant for beneficiation of minerals revealed "LIX "65N to be an excellent collector for cuprite and chrysocolla. The collector action of the LIX is proposed to result from its chelation with copper species on the surface of the minerals. Thus, the syn-isomer of LIX65N, which is unable to form a chelate with copper ions, failed also to act as a collector. The proposed mechanism takes into account partitioning of LIX between the mineral surface (to form a surface chelate) and the copper chelate dispersed in the bulk aqueous phase (either due to formation of the chelate with dissolved copper, or due to detachment of chelate formed at surface). The efficiency of the collection is dependent upon this partitioning since the bulk chelate is found unable to collect. The marked decrease in flotation obtained when copper was added to the system supports this mechanism. The dependence of flotation of chrysocolla and cuprite on pH and reagentizing time is discussed on the basis of the proposed mechanism. Batch laboratory flotation tests using synthetic mixtures of oxide, sulfide and mixed oxide-sulfide copper minerals with quartz demonstrated the ability of LIX to separate the copper minerals from quartz.

Jan 1, 1980

By WALTER M. DAKE

WITH the renewal of the contract between bituminous miners and operators, whereby a period of three years is assured without the devastating effect of irregularity of operation due to general strikes; and, with the increasing comprehension on the part of the large consumers as to the stabilizing effect of adequate storage upon prices; the coal industry has reached that period of its history in which permanence of purpose towards necessary changes is being crystallized, and these changes accomplished by the industry. It is to be hoped that during this era the phrase- " Our National Coal Problem "-will be relegated to the limbo of' antiquated expressions. That this epoch is upon us is evinced by the fact that operators are turning to consolidations, whereby financially sound companies will acquire smaller production units and place themselves in position to maintain constant supervision and control of their development and output; and, as further proof of the arrival of these changes, may be cited the entrance of additional members of the engineering profession into the many phases of management and operation, where- by the cost per ton of output will be, constantly reduced through the increasing use of modern methods and equipment. As an instance, attention is specifically called to the developments in mechanical loading, proposed and actual continuous underground transportation systems and betterment in methods of preparation.

Jan 1, 1924

By Kenneth L. Ancell

This paper traces the history and performance of a coal degasification project in the Black Warrior Basin of Central Alabama. The primary coal beds being degasified are the Mary Lee and Blue Creek. The area being developed for gas production is also scheduled for underground mining in two to seven years. The paper discusses the early data collection and evaluation. The coals are extremely gassy with some measurements in excess of 500 SCF/ton. Five experimental wells were drilled and produced. Geologic heterogeneities were encountered which affect the performance of the project. Drilling and completion practices together with well design considerations compatible with under- ground mining are discussed. Finally, the gas gathering and sales system together with the early production history is illustrated.

Jan 1, 1982

By PAUL M. Tyier

NOW that analytical chemistry has gone so far to debunk early misconceptions about minerals, the fact that the light of exact knowledge still fails to illuminate many dark corners is often overlooked. By combining the skills of the physicist with those of a chemist, the identification of minerals has become an exact science and the presence of even minute traces of impurities and extraneous elements is readily revealed by spectrographic means, Granted that we can learn all there is to know about the composition of a substance and even about its physical propertied (which latter assumption is somewhat far-reaching) it still does not follow that we clearly understood its commercial designation or utility.

Jan 1, 1941

By David Akers, Clifford Raleigh, Glenn Shirey

Under a Cooperative Agreement with the U.S. Department of Energy’s National Energy Technology Laboratory (NETL) and the Mining Industry of the Future Program, CQ Inc. is demonstrating the GranuFlow™ process for improving the recovery of fine-sized coal in commercial coal preparation facilities. The State of Pennsylvania’s Energy Harvest Grant Program is also providing funding for this project. The GranuFlow technology involves the addition of an asphalt emulsion to a slurry of fine-sized coal (<100 mesh or 0.15 mm, typically froth flotation concentrate) before mechanical dewatering in screen-bowl centrifuges. The emulsion selectively agglomerates the carbon-rich particles, resulting in increased particle size and improved recovery of the coal fines during the dewatering process. This paper summarizes the test conditions and current results for both bench-scale investigations and full-scale commercial plant demonstrations.

Jan 1, 2005

By Robert B. Hopler

This paper reviews, from the historical standpoint, the development of the commonly-used terms such as "No. 6 and No. 8" with regard to detonator strengths. The origin of the strength terminology is reviewed, and the many methods developed to compare the strength of one detonator to another are described, with the good and bad points of each method outlined. The "miniature cartridge test," very highly regarded by both the U.S. Bureau of Mines and Institute of Makers of Explosives in the 1930's and early 1940's, is described in detail, as is a test developed and used by IRECO.

Jan 1, 1992

By Douglas Robinson

This paper describes technical work done to develop a Spouted Bed Electrode Cell into a commercially viable Electrowinning Cell; (a previous paper has been presented at the ECS meeting in Paris in May of this year, with a more general overview of the cell, [1]). The studies have included hydrodynamic tests to understand the criteria for the circulating flow of metallic beads in the cell, particularly in the region at the entrance to the draft tube, and electrochemical tests to find a suitable diaphragm for extended time electrolysis. Various patent pending features were developed including a double nozzle to allow for automatic stopping and restarting of the bed, an arrowhead shaped draft tube to control the flow of beads into the entrance to the draft tube, a roof-top shaped device to control the flow of beads out of the top of the draft tube, an overflow weir to allow the continuous recovery of beads from the cell, and a family of diaphragm fabrics for extended operation. Prior to the identification of the diaphragm material, short circuits would develop within a few hours. A pilot scale cell was operated for three days, with continuous operator attention, and then for ten days with operator attention only on day shift. The cell is currently advancing to the next stage of development which will involve continuous testing in a commercial copper electrowinning facility.

Jan 1, 2003

By Krokhmai VS, Sayko OP

The paper summarises the theoretical and experimental studies which led to the development of new industrial equipment designed to recover liberated gold from placer gravity concentrates. The new technology is based on environmentally clean magnetic methods, which avoids use of mercury in the production process and obtains higher gold recoveries compared to the amalgamation technique, and which can reach 98.6 - 99.5 per cent. The complex of equipment thus developed is now commercially used at nine Russian gold mining operations. Six more such complexes are due to come on stream in 1993, some of them outside the CIS. The new technology appears to hold much promise for the recovery of precious stones (diamonds, rubies etc) semi-precious stones (pyropes, chrysolites etc) and also artificial diamonds, for which case there are encouraging laboratory results.

Jan 1, 1993

By Coulter K. W

The commercial evaluation of coking coal from bore core data will begin with a technical evaluation of the coal properties affecting coke quality. Methods currently used for prediction of coke.properties from coal analysis are illustrated but in each case accuracy of measurement and prediction should be clearly understood. It is suggested that coal be initially valued from coking properties (base value) and adjusted for chemical properties (merit value). Final evaluation of coal can only take place as coke in the blast furnace where the coke is assessed under high temperature operating conditions. The commercial value of a particular coking coal will depend on many additional factors other than the technical properties.

Jan 1, 1977

By Leroy C. Stewart

Owing mainly to the use of ethylene dibromide in the production of tetraethyl lead for gasoline treatment, there has been a tremendous increase during the past decade in the demand for bromine. In the United States, production, derived mainly as a by-product from the treatment of brines from salt wells, rose steadily from about two million pounds in 1924 to nine million pounds in 1931. In 1936, production amounted to between 20 and 21 million pounds. Much of the increase during the past four or five years has been due to the operation of the Ethyl-Dow Chemical Company&apos;s plant, which extracts bromine directly from sea water. The process employed by the Ethyl-Dow Company is somewhat similar to that in use on salt-well brines at their plant at Midland, Michigan, but whereas these brines contain around 1,300 parts per million bromine, sea water contains only 65 to 70 p.p.m.-about as much as the waste effluent in the brine process. By intensive research, however, a process was developed whereby a very considerable percentage of the bromine content of sea water could be recovered, and at a satisfactory operating cost. In its essentials, the process consists in liberating the bromine from the sea water by treat-ment with chlorine, blowing the bromine out of the water by a current of air, and finally absorbing it in a solution of soda-ash.

Jan 1, 1938

By D. W. Leyshon

The fluidized solids technique for the calcination of phosphate rock has been well established for over 10 years. This paper is intended to review the recent performance of many of the Dorr-Oliver FluoSolids* calciners. In addition, design features of these three compartment refrac¬tory construction reactors will be described and a comparison made with fuel requirements for single compartment calcination. Also presented will be certain, aspects of the use of the rock including a discussion of non sulfate sulfur in the rock. A system is described for producing a blended mixture of calcined and uncalcined rock.

Jan 1, 1972

By P. V. Faragher

A METAL or alloy finds its place in commerce in proportion to its ability to serve certain purposes better and more economically than other materials. While there is some overlapping of the fields of application of the various metals under discussion in this symposium, each one has its uses for which it is especially adapted. While aluminum is the most recent of the metals to enter the field, the development of the industry has been based on its peculiar properties, by virtue of which new uses for non-ferrous metals have been created. There has been substitution of this new metal for other members of the group but there has been a far greater development in entirely new fields. In common with the other non-ferrous metals, aluminum is resistant to atmospheric corrosion. It also withstands the action of many of the common chemical reagents, strongly alkaline substances being the notable exceptions. The outstanding properties on which the application of aluminum is based are its low specific gravity and its ease of fabrication into the forms in which it is used. It is noteworthy that this property of specific lightness is retained in all the commercial aluminum-base alloys. This statement does not apply to aluminum bronze; this is more properly a copper-base alloy, since aluminum enters into its composition to the extent of only about 10 per cent. None of the commercial casting alloys of aluminum has a density exceeding that of the parent metal by more than about 10 per cent., and some are actually lighter. In the so-called "strong alloys" of aluminum in which strengths comparable to that of mild steel are developed by heat treatment, the greatest increase in density is only slightly more than 3 per cent., and one of these, also, is lighter than aluminum. This property of lightness combined with the desirable mechanical properties of the alloys, makes aluminum especially suited for parts of moving assemblies where saving in power, as well as a decrease in stresses resulting from inertia and vibration, are of importance.

Jan 1, 1928

By R. J. McClincy

The potential techniques for the direct smelting of copper sulfide concentrates to blister copper were evaluated from the standpoint of commercial application. Many existing smelters are adaptable to direct smelting practice but only with improved control of metallurgical performance. Modified and innovative procedures for slag cleaning and metal refining, prerequisites to direct smelting, are presented and discussed. The ability to smelt directly to blister copper using existing equipment and eliminating the need to convert matte offers ,significant advantages to traditional smelting practice from the viewpoint of cost, &apos;S02 control, and process simplicity.

Jan 1, 1983

By H. C., Simpson

MANY metals by virtue of their place of occurrence as ore, and their uses are travelers! Iron and steel, for instance, is one of the greatest of travelers in the form of ships and the romance of iron in this respect is only just beginning to be superseded by the stories which can be told of the travels of aluminum and its alloys, used in the building of airplanes. Tin is a traveler from the Straits Settlements to this country and Europe, for use in the canning industry; afterward traveling all over the civilized world as a part of the container for preserved foods. Silver is somewhat of an aristocrat, when its uses are measured against those of the baser metals. From earliest times it has been used for adornment (first perhaps o4 the person and later for the embellishment of weapons and&apos; buildings), for the making of fine ar¬ticles used in the household, and as money. While its uses have been widened by the discoveries in chemistry, electricity and other sciences, its early uses are still much in evidence in our modern life.

Jan 1, 1928

By Salinger, Herbert

WITH the large amount of metallurgical re- search work now being done and the constant effort of the engineer to effect economies of operation, I think it is a safe prediction that the next few years will see a great change in the handling of mine products. The well-managed mine, with sufficient ore reserves to warrant the necessary plants, will increasingly call upon the metallurgist and chemist for the solution of its problems. Shipping sorted ore or concentrate to the nearest smelter will not be the course followed. From ore to metal, or at least to a product directly salable to the consumer, will be the practice followed. As a consequence, mine managers will be increasingly interested in metal trade problems. By metal trade I mean the buying, selling, shipping, handling, and all the practices, forms and customs that go to make up the trade.

Jan 1, 1928

By T. Nagano

Mitsubishi Metal Corporation started the development work of a new process for continuous production of copper in 1961. After a series of experimental and semi-commercial operations, the first commercial plant of the Mitsubishi Continuous Copper Smelting and Converting Process was put into operation in March, 1974. The new plant, which has a design capacity of 4,000 metric ton copper per month, was built within the premises of Naoshima Smelter, replacing the old No.1 reverberatory smelter there. The SO2-rich exhaust gas from this new plant is blended with the off-gas of the No.2 reverberatory furnace for production of sulfuric acid and the overall emission of sulfur at Naoshima has been greatly reduced. The operation of the continuous plant has been satisfactory and several advantageous features of the Mitsubishi Process have been proven on a commercial scale. This paper first gives a brief description of the history of the development work and the characteristic features of the process. The paper then describes the new commercial plant and operating data obtained so far.

Jan 1, 1976