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By S Arya, A Bhandari

Dust emissions by blasting are of concern to both mine operators and surrounding communities. The quantity of dust produced, and the effects of its dispersal depend substantially on geological, blasting and meteorological conditions. This paper provides details of methods used to quantify the amount of dust produced after collecting samples using high volume dust samplers, and the difficulties encountered in satisfactory dust sampling and quantification. Also described are practical dust reduction methods by using water filled ampoules and water filled balls.

Jan 1, 2004

In the past five years, there has been an evolution in the assessment and control of mining risks in the New South Wales coal mining industry. This change has involved the development and use of structured, systematic, team-based risk assessment exercises to identify, assess and control unacceptable risks to people, equipment and production. The outcomes have improved the management systems in the mine. This paper discusses the evolution of the risk assessment approach in equipment design and mine operations, as well as the specific risk assessment methodology. The paper also presents the reactive side of risk management, the method of investigating failures in the management system, usually referred to as incidents or accidents.

Jan 1, 1994

Gold mining commenced at Telfer in Western Australia in 1977. Ore mining was carried out by owner equipment and personnel with waste stripping by a contractor. Initial ore reserves were in predominantly high grade, geologically simple reef structures. A mining method was developed using dozers to selectively mine the ore bearing horizons with a minimum of dilution. As the mine has developed the simple, high grade ore reserves have been progressively replaced by more geologically complex, lower grade reserves. In turn, mining methods have evolved to extract this ore by the most appropriate methods. On-going attention to ore mining practices will ensure that project profitability and viable mine life are optimised.

Jan 1, 1986

Human resources (HR) practitioners use a general suite of tools that they adopt to suit their company needs and profile. This paper will cover the main areas of a selection and recruitment process from applying for a job, resumT writing, participating in an interview finalising the job offer. A holistic recruitment process has many facets to it. These processes can be quite sophisticated and technical but at the end of the day they are designed to identify talent. A recruitment process will generally include: ability testing (usually online);telephone interview;face to face interview;behaviourally based interviews;psychometric assessments;presentations;simulations (independent or team based); and assessment centres, etc. Understanding the basis of these tools will go a long way to prepare you for the job market, enhance your performance in a recruitment process and stand you out from the pack.

Jan 1, 2008

Green policies have gained momentum since the 1972 Stockholm Environment Conference. The environmental movement has influenced political initiatives both in New Zealand and abroad. Governments and international institutions have addressed local, regional and global environmental issues with varying degrees of success. New Zealand so far has not supported the United Nations' call for sustainable development in a,consistent manner.New institutions and new rules for resource management mean there are opportunities to look after the land in different and more ecologically sensitive ways than has happened in the past.The increasing influence of regional councils in resource management planning will have important implications for mining and mineral exploration. These trends are discussed and possible future events outlined.

Jan 1, 1990

In his letter of resignation as General Superintendent of the Broken Hill Associated Smelters (BHAS) prior to taking up aconsulting position at imperial Smelting, G.K. Williams wrote that he considered his major contributions at BHAS were:the development of large scale sintering machines;the double tuyere-row blast furnace; continuous lead refining.Despite his well deserved reputation as a scientist, based on his advancement of the metallurgical chemistry underlying lead refining processes, Williams reveals that he considered commercial implementation as the ultimate measure of technological success. Furthermore, he clearly did not differentiate between the scientific and the empirical as a means of achieving that end.

Jan 1, 1985

By Randall C

Energy studies have been undertaken at a number of open coal mines in the Hunter valley. A range of energy efficiency benchmarks and targets have been established, which, when applied across coal mines, will assist in leading to a significant improvement in energy efficiency in the coal mining industry in NSW, thereby leading to an improvement in environmental performance. Typically, energy efficiency improvements of 20 per cent and higher appear possible at many mines leading to a commensurate reduction in this controllable operating cost, ie energy. On the basis that annual energy costs and net profit are similar for many mines, a reduction in energy costs by 20 per cent will lead to increase of 20 per cent in net profit.

Jan 1, 1995

By Miskelly N

Construction of the Ranger uranium project located 230 kiss east of Darwin in the Northern Territory commenced in January 1979. Energy Resources of Australia Ltd (ERA) was incorporated in February 1980 to acquire all the rights in the project. The total cost to ERA of these rights was $407 million, made up of $125 million in cash to the Federal Govern- ment and the issue of 125 million $1.00 shares at par, plus a payment of $16 million in cash to each of Peko-Wallsend Ltd (Peko) and EZ Industries Ltd (EZ).

Jan 1, 1983

In recent years, wide consideration has had to be given to methods of improving the condition of the mine environment in many coal mines, and significant developments and changes have evolved. Thus even after substantial increases inòair flow rates at the working place (they have increased over three fold in the last generation), environmental conditions have arisen for which it has been necessary to introduce or consider: i) additional ameliorative measures, such as good housekeeping; ii) layout changes: such as Y or Z layouts; iii) homotropal ventilation; and iv) air conditioning. In certain countries, consideration has been given also to: v) additional payments reduced working times; vi) heat acclimatisation programmes; and vii) the use of cold or cooling suits At many hot and humid mines, the principal benefits from adopting (i), (ii) and (iii) have already been realised. At such mines,

Jan 1, 1983

By Hedley TP

Success for underground coal mine operators in the 1990's and beyond will be dependent upon better understanding of the dynamics of their operating environment, and extension of emerging technologies to reach new levels of output and productivity. The Collieries Division of B.H.P. Steel International Group clearly identifies with the concept of business/product life cycles - and the need to adopt strategies that can drive the business successfully into the future. Three main thrusts within BHP Collieries Division relate to: 1) Detailed assessment of current mines to determine: a) The real output potential of the current facilities. b) What factors now inhibit the full potential from being realised. c) Opportunities that exist to enhance overall mine performance. 2) Based upon the findings of these studies, putting into place cost effective strategies and systems for the ongoing "tuning" of the mine. 3) of new/improved technology primarily in areas of: a) Coal cutting and underground coal clearance. b) Controlling the overall mine gas Regime.

Jan 1, 1987

A new two-metre column self-heating test procedure has been developed at the University of Queensland, which clearly shows the hot spot development phases that take place in bulk coal self-heating. The column results provide a more reliable indication of the self-heating propensity of coal than small-scale index tests. At the same time, off-gas evolution patterns associated with hot spot development are obtained, including the recognition of hydrogen evolution from oxidation at temperatures less than 80¦C. Subtle differences in off-gas evolution from self-heating between gassy and gas-drained coal are also apparent. This new approach to coal self-heating assessment offers an opportunity to further the understanding of the complexities of spontaneous combustion and will enable more accurate risk assessment for the coal industry.

Jan 1, 2005

By Albinson T

Mexican epithermal deposits can be broadly grouped into two types based on their contained metals, distribution, associated igneous rocks and fluid inclusion compositions. Silver-gold deposits (e.g. Tayoltita) mostly occur in the western part of northern Mexico where host rocks consist of Eocene, intermediate composition volcanic and intrusive rocks; fluid inclusion studies indicate that mineralizing fluids were _10 eq. wt. % NaCl). The distribution of these two deposit types, crosscutting major major crustal sutures, and the close spatial-temporal relationships between mineralization and magmatism, together suggest that magmatic processes were more important in the formation of mineralizing solutions, as a source of both ligands and metals, than the segments of crust hosting deposits.

Jan 1, 1995

The rnunber of Cenozoic volcanoes which has already been found in China surpasses 600. An ancient Chinese tourist, Xu Xiake (1587-1641 in the Ming Dynasty), mentioned in his travel notes the volcanoes and hot 'springs in Tengchong, a country of the Yunnan Province, 400 years ago. In 1927, the geologist, Yun Zhanli, expounded generally on the recent volcano distribution in China. In the '70's, China not only accomplished aerial photography and produced topographic and geological naps covering the whole country, but also obtained a new understanding of the geographic distribution and process of development of the Cenozoic volcanoes through Landsat imagery; interpretation and ground verification, together with C14 isotope dating and analysis of volcanic rocks.

Jan 1, 1987

By Ellson I. G

Advantage has been taken of the need to build the new mining town of Shay Gap to incorporate a new standard of living in an isolated area, which suffers from climatic extremes. The various problems associated with living in the Pilbara area of Western Australia are outlined, together with their effect on the design of Shay Gap.

Jan 1, 1973

By Grainger A, Dawkins G, Lysaght A, Kennedy R

Maintenance management improvement projects were undertaken at several BHP Collieries Division mines pursuing.the objective of achieving better structured maintenance procedures. Efficiently structured maintenance and optimum asset use are interdependent and productivity and computer models assist towards that objective. Definition of aspects of maintenance and analysis of the nature of equipment and materials, workloads and tasks, lead to more effective planning and scheduling of maintenance. The quality, standards and procedures of records must be suitable and adequate for storage and future retrieval. Total Quality Control initiatives and improvement projects even extend into spheres of customer/supplier relationships and problem solving teams as well as the more recognisable standards of management and performance factors in maintenance. All such factors contribute to a Maintenance Management Matrix to provide a better structured approach to economic maintenance management in the capital intensive coal mining industry.

Jan 1, 1991

By Kwok S, Haemmerle A

Treatment methods for a low grade deposit at Mt. Fitch near Rum Jungle, N.T., were investigated. Physical beneficiation of the ore, sulphuric acid leaching, carbonate leaching and various methods of uranium extraction from the leach liquor were studied. Although the deposit occurs in a carbonate environment, acid leaching of the ore after beneficiation by radiometric sorting appears to be the most economic treatment method. Uranium would be recovered from the leach liquor by solvent extraction.

Jan 1, 1970

By Weller KR

Computer programs are described which help the metallurgist to process sample data from a plant survey; to carry out simple mass balance calculations; to present the results of circuit and equipment performance in convenient form; and to simulate the circuit response to changing operating conditions. The uses and limitations of these programs are explained by following through a case study of the sulphide flotation circuit at Cleveland Tin Ltd. The circuit was sampled, the data analysed, and some process inefficiencies established. Simulation calculations were then made to provide information on which to base decisions regarding possible circuit changes aimed at improving performance.

Jan 1, 1983

In China the hydrogeological type of solid mineral deposits can be divided into A. Mineral deposits with fissure water; B. Mineral deposits with pore water; and C. Mineral deposits with karst water. The hydrogeological conditions of mineral deposits with fissure water are relatively simple with the exception of a few cases. Mineral deposits with pore water are few but great amounts of ground water can be encountered in the mine accompanied by floating sand or slope failure during the exploitation. Mineral deposits with karst water are complex in their hydrogeological conditions. Enormous inrushes occur frequently in the mines of north China; Karst collapses are a serious matter in the mines of the south; Subterranean river and conduit systems are often encountered in the southwest. This paper will give full discussion on these features and put forward a way of combating and controlling the groundwater problem in accordance with type and feature.

Jan 1, 1988

The processes most likely to be adopted for beneficiating ores or concentrator streams containing a large proportion of particles finer than 10 um are froth flotation, selective flocculation, wet magnetic separation and selective leaching. Flotation will be made more efficient for very fine particles if ways can be found to selectively flocculate the valuable mineral beforehand (floc-flotation), to produce smaller bubbles and to reduce entrainment of ultrafine gangue. Schemes for selective flocculation have proved difficult to implement because of the delicate balance between surface forces (electrostatic, dispersion, hydrophobic) and hydrodynamic forces, that determines flocculation, and the changes which occur to particle surfaces through hydrolysis, oxidation-reduction and cross-contamination between minerals in aqueous suspensions. The search for a better understanding of selective adsorption of flotation collectors and flocculants continues and will be particularly important for the practical success of selective flocculation and selective magnetic coating.

Jan 1, 1986

By Baafi EY

Deposits of gold, silver and other precious metals often display a high variability of grade values, usually a very low average metal content and are frequently not easy to sample reliably. The characteristics, together with the volatility of precious metal prices, make evaluations of precious metal deposits extremely difficult to make. Geostatistical estimation techniques can be used to make grade estimates of precious metals and to assess the reliability of these estimates. Two case studies are presented.

Jan 1, 1987