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The subject of government involvement in industry is, to say the least, a touchy one. For many it conjures up thoughts of socialisation or nationalisation. For others it is a desirable objective and is seen as a means of social reform by giving government a greater say in the control and distribution of human, financial and natural resources for the betterment of the community. Whatever your point of view, it is difficult to deny that government involvement exists to lesser or greater degrees in all industries. The mining industry is no exception and the degree of government involvement is probably greater than it is in other industries. I think it is important to remember when talking about government involvement in industry to recognise that there are different types of involvement and that all governments have a right, if they so desire, to become involved in whatever way they choose. The decision of a government to increase its direct or indirect involvement must, of course, be taken in the national interest. Governments, if we are still old fashioned enough to believe in ministerial and electoral responsibility, must make up their own minds about whether their actions are in the national interest and they must be prepared to accept the consequences of that action, good or bad. For instance, they must decide

Jan 1, 1975

Traditional methods for monitoring, and hence controlling, pyrometallurgical processes rely heavily upon the skill and experience of operators. A skilled operator will usually achieve consistent, though often conservative, results, whilst an un-skilled operator will require considerable time and training to achieve the same results. Semtech Metallurgy AB have demonstrated that continuous and precise control of pyrometallurgical processes can be achieved through on-line analysis of pyrometallurgical flame off-gas using optical spectroscopy. The feasibility of the technology has been demonstrated on a large number of full-scale tests at production plants and by several commercial installations. Evidence suggests that installation of this technology, called Semtech Optical Production Control (OPC), has resulted in considerable economic benefits to the plant efficiency and asset life. These economic benefits are believed to be a direct result of improved objective on-line control. Technically the following benefits have been demonstrated: improved metal grade control, reduced metal losses, reduced processing time, and improved personnel safety. SemtechÆs OPC is a non-intrusive technology which relies on the fact that the composition of the vapour phase above a high temperature melt is closely related to the instantaneous status of the melt. This enables on-line real-time analysis of the furnace melt to accurately determine melt status and in particular reaction endpoints. Originally developed for on-line monitoring of copper converting in a Pierce-Smith vessel the field of applications for the technology is steadily growing. This paper introduces the Semtech OPC technology; discusses various applications and outlines the demonstrated benefits.

Jan 1, 2002

By Channon W, Dube M, Makwana M, Kerfoot D. G

In early-1995, the Bindura Nickel Corporation commissioned a pressure leach plant at its Smelter and Refinery complex located in Bindura, Zimbabwe. The novel pressure leach process was developed by Sherritt to treat the nickel-copper sulphide residue produced from the original atmospheric leach circuit. The process extracts essentially all the nickel from the nickel-copper sulphide residue under non-oxidising acid pressure leach conditions, thereby producing an upgraded copper sulphide residue suitable for smelting and refining to electrolytic copper. The commissioning of the pressure leach plant was relatively smooth and design conditions were achieved within six weeks of operation. This paper presents a brief description of the process development and the plant design, followed by highlights of the plant start-up activities and summary of the plant performance.

Jan 1, 1996

By G A. Davis, D G. Laughton

The great variability of mineral and energy prices has motivated some governments to incorporate a windfall profits tax into their mineral taxation regimes. Windfall profits taxes are a means for governments to capture additional mineral revenue when mineral prices are considered higher than some historic level. Governments need to be aware of the effects of such contingent taxes on the exploration, development and operating decisions of mining companies. Mining companies need to be able to calculate the full impact of windfall profits taxes on the economics of their projects. This paper examines the valuation of a multi-phase copper-gold project in the presence of a windfall profits tax. Real options Monte Carlo simulation is used to characterise the different exposures of the mine owner and of the government to the risky cash flow streams that they receive from the project. The results highlight that Monte Carlo simulation paired with the real option valuation method is able to account appropriately for the differing risk exposures, while the traditional discounted cash flow valuation model is not. Our key conclusion for governments and mining companies is that the impact of contingent tax and royalty terms can and should be assessed using advanced valuation techniques, and the results used to improve contract designs under the constraint of actual and perceived fiscal system stability.

Jan 1, 2007

In recent years there have been a number of excellent towns built for mining communities in remote parts of Australia. Planning has been thorough, and very large capital expenditures have been made by companies to provide high standards of accommodation, services and amenities. But so often the phrase 'company town' comes to be applied, expressing the frustrations of the residents, working for a single employer who dominates their lives, and of the company, which would prefer not to have to build and operate a town. The much-vaunted early success of some iron ore, bauxite and coal projects has led to a belief that the success of all mining projects is assured. Those holding this belief ignore the vagaries of mineral deposits and of markets, and the need to amortise large high-risk capital expenditures, much of which is spent on social and industrial infrastruc- ture. This expenditure on infrastructure does not have to be

Jan 1, 1975

Dartbrook (Hunter Valley and South Bulli (Southern Coalfield) Collieries provide contrasting settings for gas sorption studies. Gas compositions at Dartbrook are dominated by carbon dioxide, with minor methane, while those at South Bulli are dominated by methane with minor carbon dioxide. Total gas contents at Dartbrook are also significantly greater than those at South Bulli. The two collieries are also contrasted in terms of coal composition and mining environment. Dartbrook Colliery mines a relatively small sectionb(4m) of very thick seam (up to mapproximately25m); the coal is vitrinite-rich, high volatile bituminous. South Bulli mines most of the seam thickness, with coal being an intertinite-rich, medium volatile bituminous coal.Coal samples have been collected from in-seam gas drainage holes for evaluation of relative gas desorption rate (methane versus carbon dioxide). Following adsorption isotherms, petrography, chemistry (proximate and ultimate analysis) and pore structure analysis (carbon dioxide surface area, mercury porosimetry). Bomb desorption studies indicate different behaviours for methane desorption at these two collieries desorbed gas compositions at South Bulli show a small enrichment in methane content. The opposite is observed at Dartbrook. Both collieries show enrichment in CO2 in the residual content. Adsorption studies show marked variation in adsorbed gas contents for methane and carbon dioxide at each colliery and between collieries. These variations are related to differences in coal pore structure, chemistry and Petrology.

Jan 1, 1998

By Q Zhou, Y Ma, J Zhu, R L. Frost, P Yuan

A series of organoclays with different surfactant arrangements were prepared by ion exchange. The resulting organoclays were investigated using a combination of characterisation techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric measurement (TG) and N2 adsorption-desorption. In the present study, the pores within the organoclays were discussed on the basis of the micro- structural parameters, including BET-N2 surface area, pore volume, pore size, surfactant loading and distribution. The results show that both BET-N2 surface area and pore volume decrease from low to high packing density of the surfactant as the average pore size increases. Two basic organoclay models were proposed for hexadecyltrimethyl- ammonium bromide (HDTMAB) modified montmorillonites: 1. the surfactant mainly occupied the clay interlayer, and2. both the clay interlayer space and external surface were modified by surfactant. This study demonstrates that the pore structure of the resulting organoclays has a significant influence on the sorption efficiency and mechanism of p-nitrophenol onto the organoclays.

Jan 1, 2008

By Gregg PEH, Horne D, Bolan N, Stewart RB

The Tui mine site is situated on the NW flank of Mt. Te Aroha, at approximately 400 m altitude. During underground mining operations two lead-copper-zinc ore bodies were exploited and processed on site. The legacy of the mining operation is a barren dam containing over 100,000 m3 of sulphide-rich tailings. The Tui mine site is arguably the worst case of environmental degradation resulting from past mining activity in New Zealand. Although the impacted area (approximately 4 ha) is extremely small by international standards, acid mine drainage (AMD) emanating from the abandoned tailings dam and mine adits has severely contaminated local streams and prevented natural plant recolonisation of the site for more than 20 years.

Jan 1, 1995

WHEN reading reports on reefs and lodes, one often comes across the statements "short shoot," "narrow shoot," "wide shoot," & c.From a number of reports in the writer's possession, some by members of the Geological survey, it is plain that the words "short," "narrow," "wide," "long;" &c., are used somewhat carelessly.In one official report on a certain field, for instance, the reefs are described as having "short, rich shoots"; another report on the same field states that "the reefs were characterized by narrow shoots, rich at the surface." Again, Charters Towers is described as having "wide shoots"; another writer says they are "long shoots. "The writer has read again of "short shoots which went down like pipes," and of "narrow shoots of limited extent." No doubt one can make out what is really meant, but the language is mixed. It is apparent that "narrow" is meaning the same as "short," and that the shoot has not much length in a horizontal direction. Nothing is said about the thickness or width of 'said shoot, or its depth. The "wide" shoot is evidently a "long" one; its thickness 01' width and depth is not specified. When we consider these terms, it is seen that only a few words are needed, and that these few should (as they do) have a definite meaning. In the course of his mining experience, the writer has seen shoots of almost all sizes, and some have been very long (in horizontal measurement), and have been followed down for great depths, these shoots being the best type-Charters Towers, Walhalla, &c., are examples.

Jan 1, 1909

While South Africa is well endowed with mineral resources, it is generally accepted that its future will be determined more by the development of its human resources than its mineral wealth. The country has throughout its modern history suffered from an over-supply of unskilled labour and a shortage of skilled and professional manpower. There has furthermore always been an over-reliance on Whites as an internal source of professional manpower, supplemented by immigration wherever possible. Better utilisation of other population groups in professional positions has been hampered by the general lack of education and training among such groups. Although many problems still remain, there are emerging trends which are likely to positively affect the training of professional manpower in the future. The direct and indirect influences that are likely to affect professional training at the macro level include 1. government policy and objectives in respect of manpower education and training, 2. the emergence of technikons as fully- fledged tertiary education institutions, 3. demographic trends in South Africa as they pertain to education, 4. political and statutory developments in the country, 5. industry involvement in tertiary education, and 6. professional registration.

Jan 1, 1986

This paper discusses the significant land use changes that have occurred in the Latrobe Valley during 150 years of white occupation. The developments and changes were haphazard and made with little thought as to their setting or their environmental consequences. As a result many landscape and land management problems have not been addressed.This paper contends that the mistakes will continue unless an overall plan for the landscape of the area is developed and implemented. The concept of 'Greening the Valley' is introduced. It aims to provide focus for a comprehensive co-ordinated plan which caters for the need to restore the landscape and the need to provide for future land use. The plan will seek to draw on three major landscape features of the Latrobe Valley: the natural setting of the hills, rivers, valleys and forests; the agricultural land use including the forestry plantations; and the industrial complexes and urban areas.Rehabilitation of mining areas is a key element of the plan but must be put in a regional context and not be treated as an isolated function of a single organisation. A major challenge will be to integrate the worked out areas into useful and significant landscapes. The paper concludes by explaining the process that will be followed in an attempt to realise the concept.

Jan 1, 1992

By E Wan, K Stokes

Since 1978, the nickel concentrator at Leinster has been subject to continuous change. In 1971 a significant nickel sulphide deposit was discovered on Leinster Downs Station, within three years the extent of the deposit was determined. In 1978 the Agnew Mining Company began production of nickel concentrate from the Perseverance Mine and continued to do so until production ceased in 1986. In 1988 WMC purchased the mothballed project and began the first phase of many expansion initiatives. Milestones in the life of Leinster have included:open cut mining of the Perseverance orebody and the discovery of the RockyÆs Reward orebody, as well as the metallurgical challenges in treating each of these; underground mining at both Perseverance and RockyÆs Reward; construction and commissioning of the WMC grinding and flotation circuits; variations in the reagent schemes, including the introduction of æliquidÆ reagents; development of mill linings to reduce maintenance; circuit re-configuration and simplification; development of Harmony open cut; strategies for increasing throughput at the drier; and changes to tailings facilities to cope with increased throughput. This paper outlines the steps which have been required to expand the Leinster Nickel Concentrator from 650 000 tpa to 2.5 Mtpa and those steps which will be required in the future.

Jan 1, 2000

By J Player, K Braddon

High productivity mining is the key to the financial success and stability of modern mines. This can be achieved through the use of new technologies, the development of innovative work practices andoptimisation of the mining method to suit the mining environment.Big Bell Mine is a 1.7 Mtpa longitudinal sublevel caving operation at a head grade of 3.14 g/t. Annual production is 170 000 ounces of gold. The selection and implementation of bulk emulsion explosives was seen as the logical progression from blow loaded ANFO for the high tonnage rate required from the longitudinal sublevel cave.Prior to the implementation of bulk emulsions an investigation wasrequired to examine the technical and financial benefits available with the introduction of bulk emulsion. This paper examines the review process and the successful implementation of bulk emulsion explosives at Big Bell.

Jan 1, 1999

By J Walasiak

In the climate planning of mines and tunnelling with anticipated poor climatic conditions, and especially in case of longer working shifts, the main question is whether it can be reliably prevented that certain climatic limits laid down be exceeded. Working at high temperature and/or humidity can lead to reduced human working energy û a very important economic aspect û and to a risky lack of concentration on the part of the miners or to heat collapse and extremely dangerous heat stroke. With the Deutsche Montan Technologie GmbH (DMT) climate prediction programs, both the dry and the extremely significant humid heat transfer can be calculated. This is due to the high planning reliability involved. With the help of these climate prediction programs it is already possible to determine the anticipated climatic values for the operation phase as early as the planning stage of new ore or coal fields or of tunnel construction projects and to design the optimum air cooling system for every underground project with due regard to technical and economic aspects.

Jan 1, 2005

By Worner H. K

The paper briefly summarises the work of the Titanium Research Section in the Metallurgy Department of the University of Melbourne and mentions the development of a new electrolytic process for titanium production. This process utilises the "hot-spot" cathode technique and titanium carbide anodes. An introduction is given to three further papers on titanium metallurgy to be presented to the Institute.INTRODUCTIONThe unique combination of strength, lightness and corrosion resistance possessed :by titanium and its, alloy has made them of great interest to engineers. However, high cost, difficulties of production and limited knowledge of techniques of application restrict their usage at present almost exclusively to high priority armaments.The cost of the metal is divided between extraction and processing and much research has been carried out to devise new and cheaper methods for winning the metal from its ores. Processing costs will be reduced when production volume increases.Extraction research is proceeding rapidly overseas and Kellogg (1955, p. 72) reports that 'at least seventeen companies in the U.S.A. are interested in titanium production. Of these, two are producing the metal by a modified Kroll process, three are building Kroll plants and the remainder are in various stages of research activity. The Horizons Corporation alone is contemplating electrolytic extraction and is building a pilot plant. Steinberg et aI. (1955, p. 252, p. 332) have reported the early work done by the HorizonsCorporation on electrolysis of potassium fluotitanate and titanium monoxide in fused salt electrolytes. Of these two, the former appears to be the more attractive process.

Jan 1, 1956

By V Sahajwalla, S Shin

Research activities to classify the quality of iron oxides have a long history but most of such activities are for the existing processes such as blast furnace or DR plant. Therefore the newly developed process, such as the COREX process, needs new standardisation although some basic functions of the new process have similarity to the existing processes. Many researchers (Hauk, 1990; Cho et al, 1998) in the field of COREX process have conducted investigations since the early stages of the process development and activities are underway for further plant optimisation. As Agrawal and Oshnock (1995) pointed out, because coke is not included in the COREX reduction shaft the strength requirement of the feed materials in COREX process will be more demanding than that in the blast furnace. This condition is similar to Midrex DR plant but the main reduction gas of COREX plant is carbon monoxide generated from coal combustion while that of Midrex DR plant is hydrogen from natural gas.

Jan 1, 2000

By Keys NJ

The so-called COMAT process provides a method for leaching low grade sulphide mattes in an acidic ferric sulphate medium in such a way that non ferrous base metals such as Ni,Cu and Co are substantially all dissolved; the concentration of residual acid and dissolved iron remaining in the leaching solution is low, and a large portion of the sulphide sulphur is converted to elemental sulphur. Thus the quantity of neutralising agents required to remove residual acid and dissolved iron from the leach solution prior to subsequent recovery of the dissolved base metals is greatly reduced. The leach residue and iron precip- itate report in a readily filterable form. In this paper results obtained on a pilot plant scale are presented for the leaching of a typical low grade matte in the manner describ- ed above; for the solvent extraction and elec- trowinning of copper, and for the removal of residual acid, copper and iron from the copper solvent extraction raffinate. Processes tested on a laboratory scale for the further recovery of cobalt and nickel by solvent extraction and electrowinning, and for the recovery of sulphuric acid and ammonium hydr- oxide from the dissolved ammonium sulphate salt contained in the final plant effluent, are also briefly described.

Jan 1, 1986

The equipment and general smelter layout for the Mount Isa Copper Smelter were designed by engineers associated with the American Smelting and Refining Company and by Mount Isa staff engineers. The final notice of site was dictated by the need for 'building the smelter near the existing Mount Isa power house to enable full use to be made of the steam from the waste heat boilers. Although much excavation work was necessary before concrete foundations could be poured, the location lends itself to further expansion should it become necessary. The plant is designed and constructed to involve straight line smelting operations which include the following major steps in the overall scheme.1. Charge make-up.2. Roasthig.3. Reverberatory smelting.4. Converting.5. Refining.6. Casting.CHARGE MAKE-UPA system of proportioning bins is provided for preparing the feed mixture for the roasters, Sulphide concentrate containing 24% copper wiil be delivered by belt conveyor from the filter plant to the smelter storage patio. This is a large roofed concrete floor that provides a maximum storage capacity of 8,000 tons of concentrate. Eight proportioning bins located below but adjacent to the south end of the patio will be used for actual charge make-up from which concentrate, ore and flux will be proportioned to the feed belt and conveyed to the roaster feed hoppers. Four of the proportioning bins, 80 tons capacity each, will receive...

Jan 1, 1953

By G Mulder, M Adams

Since the introduction of raiseboring 30 years ago there have been many operational and mechanical design improvements in the raiseboring machine, its reamers and associated cutters. These have now made the technology of raiseboring a routine and practical operation within the underground mining world. Over the last decade these advances have been aided by the introduction of robust automation packages which have allowed unattended drilling and reaming, real time performance monitoring and enhancement and the rapid diagnostic investigation of mechanical and electrical abnormalities. The constraint to higher raiseboring performance is now the drill string. However when it comes to a cost-effective solution of applying the high drill string torque and tension necessary for the next step change in performance, designers have æhit the wallÆ. Whilst carbon fiber reinforced plastic composites with abrasive resistant sheaths may offer a solution, the limit of conventional steel, drill string technology has been reached. This limit to advancement is however based on the drill string being in tension and alternative solutions may exist by literally turning the raiseboring paradigm on its head. This paper describes the story of a small Australian company engaged in the design and manufacture of mechanical excavation machines, two Australian raiseboring contractors and three Australian mines going against tradition and pushing down rather than pulling up.

Jan 1, 1998

By Kissell F. N, Volkwein J. C

The U.S. Department of Interior's Bureau of Mines has the opportunity to visit many U.S. mines, including some that claim 2 to 5 times the national average of 334 raw tonnes/unit shift (tps) from a continuous miner section. In a project to assess the reasons for this high production, the Bureau conducted two studies. The first study focused on the 25 highest producing continuous miner sections. What stood out during the visits-was the quality of the labor-management relations. In each of the mines there was a positive labor/management relationship based on mutual trust and a sense that the employees were the company's most valuable resource. Discussions with labor revealed a universally positive attitude toward the company. Interviews with the mine superintendents invariably ranked the quality and attitude of workers as more important than anything else. Also during the mine visits of the 25- mine study, no engineering factors obviously stood out. Time at the face was greater than average, most were in coal over 1.52 m and the roof was generally good. Also, none of the 25 mines had to contend with high methane levels. Because this study found that a high percentage of mines were in seams less than 1.52 m thick, the second study examined thin seam mines only.

Jan 1, 1988