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The last decade has seen a dramatic change in the. size and complexity of mining and mineral processing projects in Austral- asia. Major projects of today are vastly different from major projects of the 19.50's. This change has in turn resulted in a change in the role-of consultants whose contributions have been increasingly in the provision of specialist services and less in the form of overall project design and construction supervision. It is anticipated that, the specialist function will continue to represent the principle mode for consultant participation in major, projects. However, by means' of international affiliation, the development of comprehensive engineering and project management capabilities and possibly as a result of Government intervention, it is expected ,that local consultants will assume an increasing degree of participation in.the overall project design and supervision Function.

Jan 1, 1975

By Kenneth K. Landes

So far my consulting in industrial minerals has been confined principally to carbonate rocks,-salt, coking coal, and glass sand. Much of this work has been for companies either too small for a full-time geological staff or unaware of the value of employing one or more qualified geologists permanently. It gave me considerable personal satisfaction to see several of the latter companies employ one or two full-time geologists after the completion of a consulting contract with them. One possible reason why some companies lack the wisdom to hire geologists is that they are dominated by engineers who still subscribe to the old idea that engineers are self-sufficient in all fields. They could have learned this from their professors. I once knew a Dean of Engineering who got purple in the face when a faculty committee was discussing the financing of a broad gauged engineering project and suggestions were made that assistance be obtained from the Schools of Business and Law and from some of the science departments tie pounded the table and shouted "Engineers are trained to handle all this!" In teaching engineering geology some years ago I used to tell the class repeatedly that the course would not make them geologists, that the purpose was to teach them

Jan 1, 1972

By J. H. Walsh

IN THE DEVELOPMENT of procedures for the separation of minerals, the choice of reagents for flotation is frequently determined by the extent to which a given mineral is wettable by water. Measurements of the contact angle of an air bubble on wet mineral surfaces are often used in the laboratory to estimate the wettability of the surface. For the results of these measurements to be reproducible, the surface of the mineral must be polished to a mirror-like smoothness and must be free from oily contamination. Elaborate procedures for preparing mineral surfaces have been developed by Wark ( 1) and Taggart (2), and these procedures have been generally accepted as adequate for their purpose. The polishing techniques, how-ever, have certain inherent disadvantages which make it impossible to assess the effects of polishing, entrained abrasive, and adsorbed gases on the wettability of the mineral surface.

Jan 1, 1957

By W. H. De Blois

Introduction In the contact process for ?the manufacture of sulphuric acid, sulphur dioxide gas - produced by the burning of sulphur or of sulphur-bearing ores, or as a by-product in the treatment of sulphide ores - is made to combine with the oxygen of the air to form sulphur trioxide, which then only requires the addition of water to form sulphuric acid. The substance, as for example platinum, causing this combination is usually referred to as a catalyst, a convenient term, in the definition and explanation of which many pages have been written. Catalysis is now a comparatively common means of effecting chemical combination, but if the question were raised here tonight as to what actually goes on when this apparently innocent third party unites the parties of the first and second . part, without itself being altered in any way, I am afraid even our most learned members would have to confess their inability to entirely explain the phenomenon; for although the subject is under investigation, there is still much to learn. The contact process, however, is one of the outstanding achievements in chemical engineering. ? From the standpoint of the difficulties involved and the time absorbed in their solution, it probably stands alone in the field of technical chemistry. In fact, the manufacture of sulphuric acid has, from the earliest days, been surrounded with problems which have interested the ablest chemists. The Chamber System Although this paper has particularly to deal with the contact process, it may not be amiss to refer briefly to the chamber system, which was, and still is, a most important factor in the sulphuric acid industry.

Jan 1, 1927

By Harrison Schmitt

THE definitions of the terms commonly used in connection with metamorphism at elevated temperature near igneous contacts are re-examined. As the study of tactite zones associated with igneous contacts progresses, more and more emphasis is put on the localization of the ore by structural forms. The generally early age of the silicates and late age of the sulphides is well established. Postsilicate structural deformation is likely to localize ore bodies. The silicates are often replaced by the ore minerals. We may not be far from proving that the elements involved in the formation of silicate aureoles are merely normal "volcanic" emanations, that silica, lime, magnesia, and alumina and probably soda and potash are likely to undergo local transfers only. The work of Newhouse suggests the agents of the formation of sulphides in deposits of various classifications are the volcanic emanations.

Jan 1, 1947

By B. Grosso

The National Italian Regulation concerning environment protection imposes that industrial areas are provided with systems aimed at preventing the circulation of contaminated groundwater. These systems can be static or dynamic and operate basically by intercepting the contaminated flow. Their effectiveness, realization time and costs depend on the intervention type and on the features of the specific site. The selection of the best solution is complex and the results obtained by this selection may be affected by residual risks related to the uncertainty of the hydrogeological and geotechnical characterization of the site. With regard to the industrial area of Portovesme, located in the south of Sardinia, the paper presents the analysis of alternative interventions aimed at the protection of the groundwater. The attention is focused on the evaluation of their effectiveness, impact on environment and, finally, time and costs of construction.

Jan 1, 2008

By Carl O. Thieme

INDUSTRIAL specialization has rapidly created a demand for new and better alloys. A more thorough understanding of the requirements of specific industries and the discovery of processes by which it has been made possible to utilize certain metallic elements in larger quantities, together with greater purity in most virgin metals, has resulted in a great increase in the number and variety of alloys. This increase in the number of elements entering into non-ferrous alloy manufacture has increased the contamination in secondary metals, as received by the smelter. In order to successfully refine scrap of a much more complex nature it has been necessary for the smelter to install new equipment and to constantly search for new methods of refining as well as to improve the methods already in use. In some instances it is largely responsible for specialization in the secondary metal industry. It is usually necessary to remove the contaminating impurities in scrap or eliminate to a degree not objectionable, no matter how introduced. In order to know what metals or elements are of an objectionable nature, the smelter must make a study of the effect of single elements and combinations of elements on many of the physical and mechanical properties, such as strength, ductility, color, hardness, casting soundness, etc. The smelter of secondary metals must be able to utilize scrap materials of all kinds, for, sooner or later, most fabricated metal parts and the waste products formed during the process of manufacture find their way to the smelter. In addition, the smelter, in contracting for salvaged material from the producer, gets some undesirable and unusual materials. The value of secondary metals and the importance of their recovery has increased in recent years and it is no longer sufficient to recover the base metal only, such as copper from copper-bearing material, but it is essential that other elements present be recovered and converted into useful form. This paper will deal not with the smelting and refining or separation of impurities from secondary metals but an attempt will be made to show the increased value of metal scrap when properly segregated and in a less contaminated condition. There are five principal reasons for contamination in secondary metals: New and unusual alloys, productive methods,

Jan 1, 1928

By Carl Thieme

INDUSTRIAL specialization has rapidly created a demand for new and better alloys. A more thorough understanding of the requirements of specific industries and the discovery of processes by which it has been made possible to utilize certain metallic elements in larger quantities, together with greater purity in most virgin metals, has resulted in a great increase in the number and variety of alloys. This increase in the number of elements entering into non-ferrous alloy manufacture has increased the contamination in secondary metals, as received by the smelter. In order to successfully refine scrap of a much more complex nature it has been necessary for the smelter to install new equipment and to constantly search for new methods of refining as well as to improve the methods already in use. In some instances it is largely responsible for specialization in the secondary metal industry. It is usually necessary to remove the contaminating impurities in scrap or eliminate to a degree not objectionable, no matter how introduced. In order to know what metals or elements are of an objectionable nature, the smelter must make a study of the effect of single elements and combinations of elements on many of the physical and mechanical properties, such as strength, ductility, color, hardness, casting soundness, etc. The smelter of secondary metals must be able to utilize scrap materials of all kinds, for, sooner or later, most fabricated metal parts and the waste products formed during the process of manufacture find their way to the smelter. In addition, the smelter, in contracting for salvaged material from the producer, gets some undesirable and unusual materials. The value of secondary metals and the importance of their recovery has increased in recent years and it is no longer sufficient to recover the base metal only, such as copper from copper-bearing material, but it inessential that other elements present be recovered and converted into useful form.

Jan 1, 1928

By Carl Thieme

INDUSTRIAL specialization has rapidly created a demand for new and better alloys. A more thorough understanding of the requirements of specific industries and the discovery of processes by which it has been made possible to utilize certain metallic elements in larger quantities, together with greater purity in most virgin metals, has resulted in a great increase in the number and variety of alloys. This increase in the number of elements entering into non-ferrous alloy manufacture has increased the contamination in secondary metals, as received by the smelter. In order to successfully refine scrap of a much more complex nature it has been necessary for the smelter to install new equipment and to constantly search for new methods of refining as well as to improve the methods already in use. In some instances it is largely responsible for specialization in the secondary metal industry. It is usually necessary to remove the contaminating impurities in scrap or eliminate to a degree not objectionable, no matter how introduced. In order to know what metals or elements are of an objectionable nature, the smelter must make a study of the effect of single elements and combinations of elements on many of the physical and mechanical properties, such as strength, ductility, color, hardness, casting soundness, etc. The smelter of secondary metals must be able to utilize scrap materials of all kinds, for, sooner or later, most fabricated metal parts and the waste products formed during the process of manufacture find their way to the smelter. In addition, the smelter, in contracting for salvaged material from the producer, gets some undesirable and unusual materials. The value of secondary metals and the importance of their recovery has increased in recent years and it is no longer sufficient to recover the base metal only, such as copper from copper-bearing material, but it is essential that other elements present be recovered and converted into useful form.

Jan 1, 1928

This paper characterizes the copper cycle, that is, the flows of copper entering and leaving the African economy over a one-year period (1994). The major flows over the entire life-cycle of copper are examined; these include production (mining, milling and refining), fabrication of semi-products and manufacturing of finished products, use, and the waste management system. The results reveal that substantial amounts of copper (of order705 Gg/yr) are mined in Africa; of that amount, about 70 per cent is exported following processing, 18 per cent is utilized by African fabricators, and 12 per cent is discarded. The flows of copper products from African fabricators and product imports from other continents exceed product discards by large amounts. This difference, about 0.25 kg Cu/capita/yr on average, is added to in-use stock, largely as wire, plumbing tube, and in electronics. Some 65 per cent of the copper in discard flows is contained in electrical and electronic products, where it is relatively easy to collect and process for reuse. About a third of the copper discard flows known is recycled. The actual percentage is almost certainly higher because of informal (and unrecorded) recycling. Much of the remaining discarded copper is diluted into the municipal waste stream, where recovery and recycling are probably not economically justified. Keywords: material flow analysis, resource management, material budgets, copper, stocks and flows, systems analysis, Africa, developing country

Jan 1, 2003

By Narong Thasnanipan

This paper presents the outcome of the contest on the prediction of the static axial load capacity of diameter 1.20m bored pile founded at 46m below existing ground. The test pile was constructed by wet-processed method and instrumented with vibrating wire strain gauges. Different methods used by the contestants in prediction of load-settlement characteristics are described and compared with actual load test results. Load-displacement behavior of test pile is found to be better than expected. Major difference between prediction and actual test is the higher frictional resistance of Second Sand Layer achieved in the actual load test. The hyperbolic load transfer method used by one of the contestants was applied to back-analyze the load-displacement characteristics of the test pile at different conditions.

Jan 1, 2006

By Sorokin AP

The main regularities of the tectonic history of the Circumpacific belt's Asian segment are discussed. The established longitudinal metallogenic zoning is characterized by essential copper specialization being replaced in the.continentward direction by tin-tungsten and then by copper-gold-molybdenum and-tin-lead- zinc ones. The zones indicated show specific magmatism and ore forming fluid composition. The eastern margin of Eurasia experienced specific tectonic history and exhibits a wide variety of mineral deposits. It is composed of the Siberian and Sino-Korean cratons and of the largest mobile elements of tectonosphere like the Hyperborean, Urals-Mongolian, Mediterranean and Circumpacific belts. The Earth's Atlantic segment mobile features show deep penetration of their geosyncline-fold systems into the eastern margin of Asia. A good example is the Urals-Mongolian belt, its Intra-Asian branch being located within the continental margin. The Intra-Asian structural features have WE and NE trending, while folding process moved southward : Karelides and Baikalides are found in the Transbaikalia and the Soviet Far East (Stanovoy, Bodaibo-Patom, Baikal- Vitim, Selenga-Yablonovy fold regions)

Jan 1, 1987

By D. D. Eyer

New or improved technology will continue to drive productivity improvements through the next decade. In January 1988, I presented a paper titled, "Large Underground Mines of the 1990s? before the SME. I will follow some of the themes developed in that paper as modified by our experience in the past two years. In order for a coal company to be profitable today, it has had to reduce unit costs experienced in the past. This is because the current average realization, even accounting for a recent strengthening, remains below that of a few years ago. Doing business as was done in the past is not good enough. The coal industry needs to increase productivity in the range of 5-10% annually merely to stay even with rising costs. Underground productivity has been increasing more rapidly than that for surface mining. With the exception of the Powder River basin of Montana and Wyoming, underground productivity has caught up with that for surface mining in many regions of America. There are a number of technological factors which have attributed to increases in underground productivity and which should be factors in the future.

Jan 1, 1990

By E Yurakov, D J. Ashelford, M I. Slate

The push for increasing coal production rates continues to place increasing demands on mine management to safely and effectively control seam gas. Gas drainage strategies applied vary in both effectiveness and form. Methods employed are a function of assessed risk, gas reservoir characteristics, surface and underground access, budgetary constraints and gas utilisation potential. With the aim of establishing and optimising the effectiveness and efficiency of gas drainage systems, Australian coal miners in cooperation with gas management specialists are embracing the use of gas reservoir simulators and gas emission models. This paper discusses the evolution of gas drainage practices in Australian underground coal mines and the role of gas reservoir assessment methods in optimising gas drainage systems and gas production forecasts.

Jan 1, 2005

By R. W. Lee

The first prototype plant using the Imperial Smelting Process commenced operation in 1950. It is timely therefore to review the developments that have occurred with the process over the past half-century. A major advantage claimed initially for the process was its ability simultaneously to recover zinc and lead from bulk concentrates. This has remained a fundamental advantage, but it has been extended by the increasing treatment of secondary materials containing zinc and lead. This has been facilitated by the development of hot briquetting and tuyere injection. These techniques and their impact on the technology of the operation will be described. The other major advantage claimed for the process was its potential to achieve new levels of productivity in the pyrometallurgical smelting of zinc. This has been realised with operating furnaces producing up to 400 t/d of zinc. The technical developments that have enabled this scale of operation will be reviewed.

Jan 1, 2000

By J. C. Ingles

"A survey of possible methods for controlling cyanide concentration indicated that the simplest method would involve the use of a potentiometric technique. Such a method was suggested by a paper from the laboratory of Mines Safety Appliances, which described a method for determining hydrogen cyanide in air. In this application, the cyanide was absorbed in caustic and a silver electrode immersed in the caustic solution provided a measure of the cyanide concentration. However, our attempts to use the silver electrode in this simple manner to measure the cyanide concentration of solutions were not very successful. A study of the mechanism by which a silver electrode responds to cyanide concentration made it evident why this simple procedure is not satisfactory.Basically, the silver electrode provides an indication of the free silver ion concentration of a solution, and generally speaking, ignores the other ions' present. It can be used to measure an anion if this anion complexes silver. This technique has been used in complexing studies to determine the activities of such anions as acetate, citrate, oxalate and chloride. To do this, the electrode has to be placed in a solution which initially contains a known concentration of free silver ions. Addition of the complexing anion causes a drop in the free silver ion concentration and hence a change in the potential of the silver electrode. The change in potential can be expressed in terms of the concentration of the complexing anion, and used to indicate its concentration in the solution being analysed. The determination of chloride-ion by a silver-silver chloride electrode is an example of an application of this technique. The solubility of the silver chloride with which the electrode is coated provides the initial free silver-ion concentration. Depression of this free silver-ion concentration by the presence of the excess chloride ion of the sample solution results in a change in the potential of the electrode which is proportional to the chloride-ion concentration."

Jan 1, 1965

By R. W. Kobler

The pelletizing process for low grade iron ores has undergone continual changes since its inception over twenty years ago. These changes have necessitated filtration equipment changes in order to produce a product suitable for balling. With modern techniques it is now possible to produce pellets of 68% Fe from ores containing as low as 26% Fe. Low grade ores require fine grinding to liberate impurities This shift to finer grinds over the years has necessitated major changes in the filtration steps. Techniques are now available for producing suitable product from ores with Blaines as high as 3600 cm2/gram. This has been made possible by the development of high performance filters. Recent developments have reduced maintenance costs and produced higher production reliability. The paper discusses iron concentrate filtration from its beginning to present day design. It will be shown that the dewatering step prior to balling has gone through four generations of filters. Particular emphasis is placed upon hydraulic studies which have allowed today's optimum designs.

Jan 1, 1978

By Mike Stanley

This is a case study of an opencast coal mining operation where the physical and financial performance was improved via applying a process of transformational leadership development. [ ]

Jan 1, 2008

By S. P. Mathew

The ISASMELT Lead Process is a continuous two stage process for the production of crude lead from concentrate. It is based on the use of a top entry submerged Sirosmelt lance to produce turbulent baths in which high intensity smelting or reduction reactions can occur. The process involves oxidizing the concentrates in the first stage to produce a high lead slag. This slag is tapped continuously and transferred down a launder to a second furnace where it is reduced with coal. Crude lead and discard slag are tapped continuously from this furnace through a single taphole and separated in a conventional forehearth. Process and engineering design work for a commercial scale Lead ISASKELT plant designed to produce 60000 tpa crude lead has been completed. This plant is planned to be operational in 1991.

Jan 1, 1990

By Monger N. R

Factors leading to the decision to use Joy Continuous Miners for pillar extraction in the Burwood Colliery are outlined. A detailed description is given of the Joy 1-CM-2 Continuous Miner, including the power supply to the machine, and the method of cutting coalfrom a face. Modifications found necessary in practice are dealt with.The Joy 10 S.C. shuttle car used in conjunction with the Miner, and alterations made to this unit, are then described, together with Ancillary units for the whole installation such as transformers, motor generator set, air compressor,_ cables for power supply and water supply for dust suppression.Special arrangements were necessary to transport the Miner and Shuttle Cars through the tunnel to the Victoria Tunnel seam, and the method of overcoming the transport difficulties is discussed. Manning of the Continuous Miner unit, and final preparation andsubsequent working of the pillars is outlined. Special attention must be given to maintenance of the machines.It is concluded that the combination of Joy Continuous Miner and Shuttle Car is an excellent method for removing pillars in the Burwood Colliery.INTRODUCTIONThis paper deals with the Burwood Colliery in the RH.P. Group in which some units are engaged in the mechanical extraction of pillars with Joy Continuous Miners.In 1941, an amendment to the Coal Mines Regulation Act of N.S.W. forbade the extraction of pillars by mechanical means unless with the express permission of the Minister for Mines. As this permission was not forthcoming, no mechanical extraction of pillars took place in Australia until 1954 As it was doubtful during most of this period whether mechanical extraction would ever come about, coal generally was won with a view to maximum extraction in the first workings, thus giving rise to centre gannon bord panels and 45° angle cut throughs as shown in Fig. 1.

Jan 1, 1957