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By Kabel J. G

While a per onnel location system is primarily used to check that nobody is left in the mine at firing time, it is also useful for contacting people, uch a foremen, shiftbosses and tradesmen, who travel over several mine levels during a shift. The system installed at The Zinc Corporation, Limited, Broken Hill, uses punched coded plastic identity tags, with "In" and "Out" tag readers on each level. When entering a level, the employee inserts his tag in the "In" reader, and when leaving, in the "Out" reader. Each reader is connected to a central computer which shows who is still in the mine and their location.The system has been used on 3 levels by 21 men for a trial period of 4 months. It ha proved reliable in an underground mining environment, and employee acceptance has been good.

Jan 1, 1984

The mining industry was one of the first to be directly regulated by legislation in the 19th century when British public opinion was mobilised by reformers seeking social change. In the next wave of mining safety legislation, account was taken of technological advances in the industry, but again, the amendments were in large measure driven by public expectations following a series of disastrous mining accidents with great loss of life. The result was the prescriptive and detailed type of regulation that has, to a great extent, remained with and become a way of life in the mining industry of today. In 1970, the then British Government appointed Lord Robens, a former Chairman of the National Coal Board, to head a Committee of Inquiry to consider the arrangements then in place for preserving the safety and health of people at work and to consider and make recommendations on the need for change in the legislation governing such matters. The result was the 1972 report Safety and Health at Work which, in turn, resulted in the Health and Safety at Work etc Act 1974 (UK). This Act, which embodied the now familiar concepts of consultation with the workforce on matters relating to health and safety and the statutory application of the previously existing Common Law concept of the duty of care, became the model for much occupational health and safety legislation in many places around the world, including the various States of Australia. As a result of the `Robens style' of legislation, the regulators of the mining industry have had the opportunity to become less prescriptive and to introduce an `enabling' style in their statutes. This has not always been welcomed by the industry which has, to some extent, missed the comfort of knowing exactly what is required of it in order to ensure compliance with the legislation while appreciating the `self-regulatory' opportunities that the new style of regulation offered.

Jan 1, 1995

By Craw D

The Southern Alps in the South Island of New Zealand are currently rising rapidly as a consequence of continental collision along the Pacific-Australian plate boundary. Rapid uplift has resulted in a major thermal anomaly in the shallow crust beneath the alps. Alpine topography and associated intense precipitation, coupled with the thermal anomaly are responsible for vigorous combined topographic/convective circulation of water through the shallow crust.

Jan 1, 1995

By T Ye Koltunova an, L A. Otrozhdyonnova

This paper presents the results of studies on the development of an efficient non-cyanide technology for processing massive, finely disseminated, copper-zinc ores of the Urals deposits. Copper is mainly represented by chalcopyrite and zinc û by sphalerite. The main ore mineral is pyrite, with its content in ores varying from 50 to 80 per cent. At the present time, separation of copper concentrate at the Urals concentrating plants is achieved in a lime medium by non-cyanide technology using sodium sulfide and zinc sulfite as depressors of zinc and iron sulfides and butyl xanthate as the collector. Copper content in copper concentrates amounts to 15 - 17 per cent; considerable losses of zinc are associated with copper concentrate and final tailings. Various collectors were tested during the studies: xanthates and aerofloats with different lengths of hydrocarbon radicals, thionocarbamates, Aerofine 3418A of Cytec Industries, reagent S-703G of Mineral Reagents Int, and modifiers û sulfur dioxide, sodium sulfide and zinc sulfite, with a pH of the medium varying from 5 to 12. Optimum results of copper concentrate separation were achieved in a weakly acidic medium using S-703G as the collector and sulfur dioxide and zinc sulfite as modifiers. The copper content in the copper concentrate was increased by 4.8 per cent. Total copper recovery into the copper concentrate and zinc recovery into the zinc concentrate exceeded five per cent.

Jan 1, 2005

By B F. J Kelly

Multiple-point simulation is a family of methods used to generate conditional facies simulations that present the same spatial dependence as a user-defined training image. The main advantage of using a training image is the easy integration of geological concepts in numerical subsurface models. The strength of multiple-point methods is that it allows making the best use of geological expertise when data are too sparse for inferring a model of spatial continuity. However, despite being appealing to geologists, the multiple-point methods are often not used in practice due to the difficulty of building complex 3D training images that contain realistic features.A new framework for multiple-point simulation is presented that involves small and simple training images. The main idea is to use random transformations to expand the range of structures available in the simple training image. The training image is not regarded any more as a global conceptual geological model, but rather a basic structural element of the subsurface. Complex geological structures are obtained, whose spatial structure can be parameterised by adjusting the statistics of the random transformations, based on field data or geological context. In most cases, such parameterisation is possible by adjusting two numbers only. One advantage is that the training images are so simple that they can be easily built even in 3D. The method allows building 3D models that reproduce shapes corresponding to a desired prior geological concept and are in phase with different types of field observations, such as orientation, facies or geophysical measurements. The flexibility of the approach allows for naturally integrating different types of data. This is demonstrated on an example involving seismic data assimilation. Examples where complex 3D folded structures are built from a simple training image and a few orientation data are shown.

Sep 26, 2011

Before the arrival of the first Europeans, Aborigines living in the northern Flinders Ranges mined ochre - an earthy form of haematite used for pigment.The discovery of copper ore at Kapunda and Burra in the 1840s stimulated the early settlers to prospect further north along the ranges. Many of the new discoveries were not properly evaluated and companies were floated on the most tenuous evidence.

Jan 1, 1993

By Fee BS

This paper describes four new families of collector products which are currently being introduced at the industrial level. A brief summary of the chemical basis behind each product family will be given. This is then followed by a selection of flotation examples which illustrate the more important use characteristics that have been observed to date. It is becoming more apparent with further testing that these four new product families can offer both technical and economic advantages to the industrial flotation process operator.

Jan 1, 1993

DIVERSITY There are plenty of examples to show that diversity has been the fundamental downfall of many organisations, particularly when you consider the international position. What about core business, the return of companies to key competence directions and market focus. The stockmarket for instance defines groups and companies in key groups of core business. The expectation is that companies toe the line and do not diversify across their areas of defined expertise. In essence, the market has given notice that the requirements are to focus and stick to our core business. So what right does the conference have to suggest that diversity is the key to prosperity. Hasn't the organiser read the book, studied the history, listened to the market - obviously not. Have they got it wrong, My feeling and belief is no - the organisers have got it right. However, the matter is not as simple as first perceived. What is Diversity, or Diversification as I would prefer? Is it a product position? Is it a geographic position? Is it an expansion or change in services offered? Does a gold mining company diversify into copper or diamonds or aluminium or nickel? Does a gold miner in Australia diversify into China or Kazakhstan or West Africa? How do the two relate? They don't. A successful company will always possess a 'core competence' not so much a 'core business'. The best example of this is the service company extraordinaire - McDonalds. They don't sell hamburgers or french fries, they sell a service, a convenience, a lifestyle. The core business is hamburgers and if McDonalds were to diversify further into new styles of hamburgers, I suggest to you they would fail. But if McDonalds were to diversify into other products based on their 'core competence', provision of service, then I would suggest to you they would be very successful. The service procedure, service machine, service system, the formula, stava the rnnetant the nrnrlnrte -

Jan 1, 1996

The mmmg operations carried out by North Broken Hill Limited, necessitate the use of four shafts for the haulage of ore, men, and supplies. These are:-1. Blackwood's Shaft.-British Section, which has 100 feet intervals between levels to the bottom 800 feet level plat;2. Thompson's Shaft.-British Section, which has 100 feet intervals between levels to the bottom 1400 feet level plat;3. No. 1 Shaft.-With intervals between levels:(a) 100 feet to the 800 feet level,(b) 150 feet from 800 feet level to the 1700 feet level;4. No. {2 Shaft.-2770 feet from collar to bottom plat, with intervals between levels: (a) 100 feet to 800 feet level, (b) 150 feet from 800 feet level to the 2600 feet level. (c) 170 feet from 2600 feet level to the 2770 feet level.All shafts have two cage compartments, and the No. 2 Shaft a skip installation in addition.For the control of hoisting operations an electric signalling system is installed on each shaft, and is supplemented by a counterbalanced rope pull ("Knocker line") operating a surface gong. The latter system is shown diagrammatically in Fig. 1.Two sets of electrical equipment are used per shaft. The first, shown in Fig. 2, is that operated by the braceman or...

Jan 1, 1940

There is no good news! The market environment for raising capital for resource projects is getting tougher. The regulatory and accounting environment is fast becoming more difficult and the hurdles to successfully raising debt, lease, equity or hybrid finance are now considerably higher. As ever, well structured companies and capital issues can and will survive, if not thrive. An outline of the market and regulatory environment for successful issues is set out below, followed by some comparison of stockmarket values of resource assets compared to more technical appraisals.

Jan 1, 1990

The new field of environmental investiga tions introduces new problems of ethics, res- ponsibility, conflict of interest and technical procedures. Such investigations involve four elements: developer, consultant, approving authority and the public. It is essential that the consultant provide technical competence, speed and efficiency, impartiality and credibi- lity. Despite allegations to the contrary, it is not in the consultant's own best interest to omit, ignore or obscure significant adverse en vironmental impacts.

Jan 1, 1975

The granitoid rocks in Burma can be subdivided into three main belts viz. (1) Eastern Granitoid Belt, (2) W-Sn related, Central Granitoid Belt and (3) Porphyry Cu (Au)-related, Western Granitoid Belt. The W-Sn related, central belt Granitoids were interpreted to have generated during the continent-arc collision and the Porphyry Cu(Au)-related, western grantioid belt was emplaced in a magmatic-volcanic arc above an east-dipping subduction zone. INTRODUCTION Major tectonic domains of Burma Burma region can be subdivided into N-S trending (6) major tectonic domains from west to east (1) Arakan Coastal Strip as ensimatic Foredeep (2) Indo-Burman Ranges as Outer Arc or Fore Arc (3) Western Inner-Burman Tertiary Basin as Inter-Arc Basin (4) Central Volcanic Belt (Central Volcanic Line) as Inner Magmatic-volcanic Arc (5) Eastern Inner-Burman Tertiary Basin as Back-Arc Basin and (6) Shan-Tennasserim Massif as ensialic, Sino-Burman Ranges (Bender, 1983). The Sagaing (transform) Fault and Shan Boundary Fault form as a tectonically significant boundary between Eastern-Burman Basin (Back-Arc Basin) and continental,

Jan 1, 1987

By J M. F Clout

The low-grade clay-rich -1.0 mm fraction of fine iron ores have often proved difficult to upgrade and capital intensive to process when using traditional wet beneficiation technology including single or two stage hydrocyclone desliming, wet high intensity magnetic separation (WHIMS), spirals and final dewatering using fine screens. Very fine (<0.010 mm) clay-rich slimes simply follow the water split to the hydrocyclone underflow where it often impedes the subsequent processing performance of any downstream spirals and can result in troublesome direct dewatering of hydrocyclone underflow. The -1.0 mm fraction in goethitic iron ores is typically considered as waste. A new two-stage wet gravity separation flow sheet, referred to as the ædesandÆ process, has been designed to overcome these issues for the upgrading of low-grade clay-rich goethitic or hematite-quartz fine iron ores. The desand process is designed to treat the -1.0 mm range from -8.0 mm natural fines, to recover a -1.0 +0.038 mm higher-grade fraction by rejecting to tailings any low-grade clay-rich ultrafines and low density sand-size fine chert/quartz gangue and shale.The desand process consists of wet screens with a nominal 0.7-1.0 mm cut point which direct the undersize to hydrocyclones. The hydrocyclone underflow is then fed to upcurrent classifiers where the classifier middlings is sent to spirals and classifier and spirals concentrates are then dewatered using vacuum belt filters or fine screens. The three product upcurrent classifier is employed to further deslime the hydrocyclone underflow, producing firstly a coarse final concentrate, and then a deslimed middlings for feeding to spirals as well as a 0.100 mm clay and fine quartz or banded iron formation (BIF) sand in final overflow for feeding to the residue thickener. The upcurrent classifier middlings provides the spirals with a significantly cleaner feed material than traditional methods, with the end result that the spirals do not silt up with slimes and therefore can continue to run at their optimum. The upcurrent classifier and spirals form a complimentary pair, with the upcurrent classifier better able to send coarser, acceptable grade particles to concentrate and fine slimes to tailings whilst allowing the spiral to better reject coarser, subgrade low specific gravity particles. Test results for the Mayoko-Moussondji iron project, Republic of Congo, using upcurrent classifier-Wilfley Table (simulating spirals) gave acceptable mass recovery from run-of-mine (ROM) and Fe recovery from hydrocyclone underflow for HEMCOL (6.2 per cent mass recovery from ROM/43.1 per cent Fe recovery) and HEMBIF2 (5.1 per cent mass recovery from ROM/22.3 per cent Fe recovery) mineralisation types. The desand process also enables improved dewatering of -1.0 +0.038 mm product from a clay-rich plant feed.A number of new wet plants in the Pilbara use the desand flow sheet including FMGÆs Cloudbreak and their two Christmas Creek plants. Many potential new applications are being explored, with new iron ore plants in India as well as those being proposed for West Africa. Operational experience has highlighted the importance of providing clean process water to the upcurrent classifiers as well as ongoing design improvements including increased wear life, reduced maintenance and enabling a more steady feed rate to spirals.CITATION:Clout, J M F, 2013. Beneficiation of fine iron ores using the desand process, in Proceedings Iron Ore 2013 , pp 337-348 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By D Trembath

"One of the key risks to the success of a mining operation is the accuracy of the estimates of both the economic mineral and any accompanying contaminants contained within the ore reserve. Misrepresenting the mineralogical characteristics of the ore reserve can result in considerable financial investment in an operation that is in fact uneconomic and/or carries a significant environmental risk. This in turn can result in an unplanned closure of the operation with associated financial, environmental and social legacy. One way to minimise this risk is to undertake high density resource sampling to gain a better understanding of the resource characteristics. However, such an approach is expensive, time-consuming and often impractical. The risk of not having an accurate model is typically assessed during a feasibility study utilising a Monte Carlo simulation method or some form of sensitivity analysis. Importantly, the error margins used in these types of analyses are often based on subjective or very general criteria such as ‘professional judgement’ or an ‘industry standard’. This presentation introduces a conditional simulation method for developing a range of mineralogical distribution models. Based broadly on the method outlined in Journel and Kyriakidis (2004) the proposed approach develops this work further. It combines a geostatistical analysis of the available data with automated mine design software to provide a rigorous method for assessing the confidence in the mineralogical characterisation of the ore reserve. The process is based on simulating possible mine plans based on the statistical characteristics of the available resource sample data. These plans are then assessed against high resolution resource models generated using a Sequential Gaussian Simulation method. The outcome is confidence intervals for important characteristics of the ore reserve estimate relative to the actual resource. These confidence intervals are an objective and transparent measure important for assessing closure risks and represent an improvement over common practice.CITATION:Trembath, D, 2016. A simulation approach for improving the assessment of closure risks, in Proceedings Life-of-Mine 2016 Conference , pp 36–38 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 28, 2016

A new classification of subduction related (epithermal- / mesother-mal) gold mineralisation styles based on the tectonic framework they occur in, has been found helpful in practice. It offers a ratio-nalisation of exploration efforts during all stages of work.Methodology on the ground during first pass- and follow up explo-ration which has been found effective for the various mineralisa-tion styles is being briefly outlined.

Jan 1, 1990

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

By M Scoble, W S. Dunbar

This paper reviews methods for grade estimation in short-term mine planning for block caving. Two particular tools are used: Ordinary Kriging and Simple Kriging with moving averages. It is also considered the influence of draw characteristics on the grade estimation process. Reference is made to mine case study data and analysis. These demonstrate that operational grade estimation is not a trivial process. It must take into consideration: the grade variability (in terms of ore and dilution), sampling interval, geological and geotechnical characteristics, geometrical layout and draw characteristics. Significant improvements appear possible in short-term planning if variogram analysis, as well as kriging methodologies, are introduced into the operational grade estimation process.

Jan 1, 2000

By D L. Kennedy

Many aspects of the physical layout of manufacturing plants and storage facilities for explosives are governed by so-called quantity-distances tables. Both the British and the American tables were originally derived from an analysis of the injuries and the building damage documented by an early 20th century compilation of significant accidental explosions. However, progressive changes in explosive process technology and in building techniques have reduced the relevance of much of this historic data set. Extensive scientific research has been conducted over recent decades to characterise the potential injuries and damage from accidental explosions under more modern conditions. This presentation will showcase some of this research.**This is an abstract only. No paper was provided for this abstract**

Nov 8, 2011

The importance of proper planning, preparation, and execution of a steady state sampling campaign for metallurgical plant assessment must not be underestimated. Careful planning can increase the amount and reliability of information from an optimum number of samples and fully utilize available plant data. It requires specification of the data required, determination of run duration sampling frequency, the selection, modification and testing of sample points and cutters, as well as organisation and briefing of plant and sampling personnel. Preparation immediately prior to sampling, the conduct of the sampling campaign itself and procedures to handle the collected samples and information are discussed. Cutter design, fabrication and use are described in detail, and typical sampling situations, for ball mills, classifiers, pipes, launders, flotation cells and thickeners are considered individually. Measurement of pulp flow rate can often resolve difficult mass balance problems, and discussion of convenient techniques is included.

Jan 1, 1976

Reserves of high-grade quartz gravel, lignite, and timber suitable for the production of silicon metal and ferrosilicon on large scale occur within 40 miles of Bluff Harbour. Undeveloped hydroelectric power resources on the Clutha River are located within 50 miles of the most promising quartz gravel deposits while opencastable lignite, potentially suitable for electric power production, occurs in the same locality as the quartz gravels. A preliminary study of production economics indicates that the commercial feasibility of silicon/ferrosilicon production would depend mainly on the cost of electric power, total capital cost of plant, and the market value of the products. The proximity of Bluff Harbour is advantageous for the export of products.

Jan 1, 1971