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The goal of the Bureau of Mines, U. S. De- partment of the Interior, diesel engine research program is to reduce exhaust emissions and mini- mize the risk of fires and explosions caused by the use of diesel-powered equipment in under- ground mines. Significant results of research conducted during the last 5 years are briefly described, with references to published reports on specific topics. Topics covered here include brief discussions of a newly completed diesel research laboratory, the effects of a fuel addi- tive on diesel exhaust particulate matter, the effect of diesel engine maintenance on emis- sions, a diesel particulate filter for equipment used in underground metal and nonmetal, and coal mines, and lastly, the prototype hydrogen- powered mine vehicle. These research accomplishments could favor- ably affect the mining industry by reducing the health and safety hazards associated with the use of diesel-powered equipment in underground Mines.

Jan 1, 1988

By I Ametov, G Levay

It is now common practice to use substantial amounts of recycled water in mineral processing plants to minimise both environmental discharge and withdrawal of fresh water from often limited water resources. Recycled water additions to process water are frequently obtained from sources such as tailings dams, tailings thickeners and concentrate dewatering. It has been suggested for some time that addition of recycled water to process water will impact the quality of the process water and that changes in water quality may influence flotation performance. To date, investigations of process water quality changes as a result of water recycling have been limited and as a consequence there are very few data available to substantiate these ideas. Thus the impact of recycling on process water quality remains largely unquantified. Over recent years we have conducted water quality studies at a number of mineral flotation plants with varying degrees of water recycle. This paper describes the results of these investigations, including data which suggest that build up of salinity due to recycling while it occurs, is reduced by fresh water make-up. The fate of flotation reagents such as collectors, promoters, frothers and flocculants during process water recycling has also been investigated. Results show that process water concentrations of these reagents vary from plant to plant, but that, with the exception of frothers, most reagents are generally removed from the system through mineral adsorption. In general, the results of these investigations suggest that recycling process water will not result in continuous increase in solute concentrations as appears to be the commonly held view.The effects of changing water quality on flotation can vary. In many cases, flotation conditions can be optimised to suit the water quality, while in others, treatment of the water may be necessary to obtain acceptable plant performance.

Jan 1, 2009

While the potential for the discovery of new high grade resources exists, it is almost inevitable that the ore resources used to provide society's ongoing demand for primary metals will deteriorate over time as the higher grade reserves are exploited first and are progressively depleted. This deterioration in quality of metallic ore resources will bring about significant interactions with other resources such as energy and water, resulting in an increase in the amount of these resources required per unit of primary metal production. In this paper it is shown that as ores deteriorate in quality, the contributions of the mining and mineral processing stages to the life cycle-based embodied energy and water of primary metal production will increase significantly. Therefore efforts to reduce the impact of deteriorating ore resources on energy and water consumption should focus on these stages.   The results from life cycle assessments of the production of various metals by a number of different processing routes, particularly copper and to a lesser extent nickel, have been used to identify a number of opportunities and technologies for reducing the energy consumption in the mining and mineral processing stages, including: comminution, eg high pressure grinding rolls, stirred mills, ore sorting, preconcentration, advanced blasting techniques, advances in diesel technology for loading and hauling, alternative processing routes, eg heap leaching, in situ leaching, water treatment and re-use, water quality 'fit for purpose', dry processing, floating modules to reduce evaporation, and paste thickeners. All the above and existing developed flotation technologies can impact on the mineralogy of the concentrate supplied to the smelter. Removal of gangue minerals early on in processing may have further downstream process implications on fuel and water requirements. The above technologies are in various stages of development, with some more advanced than others. However, all can be expected to play their part in improving the sustainability of the Australian mining industry.

Jun 1, 2010

By M Roche, W J. Huxley

Finding a balance between practical and acceptable groundwater management, and providing for the needs and impacts of mining developments remains a challenge. The changes that accompanied the recent implementation of water reforms have provided greater flexibility for the water manager and greater certainty for the resource user. However uncertainty associated with understanding of complex aquifer systems, balanced against providing for the needs of mining developments, the rights of existing water resource users and expectations of the broader community have not diminished the conflicting issues faced by water resource managers and resource developers. Licensing under the Water Act 2000 provides the regulatory link with the taking of water for water supply purposes or as a consequence of the mining activity. This paper outlines key elements of sustainable water resource management involving certainty of access to water and adaptive environmental management that are delivered through conditioning the water licences issued for the particular mining development. Implementation of this approach is illustrated through a case study involving the BHP Billiton Cannington Mine in North West Queensland.

Jan 1, 2003

By Johnson RD

The variation in coal properties and the coal seam reduced level can be analysed using partial trend-surface analysis techniques. For the area studied seam reduced level and seam thickness data from the Bulli Coal yield trend-surfaces with a high coefficient of determination, since they have relatively small systematic local and random components in their overall variation. Sulphur content appears to have no significant re.gi_onal trend, and phosphorus content has a very weak regional trend. Other analytical variables have regional trends which are of intermediate strength. The strike-directions of.the statistically significant first degree! trend-surface are similar, sug-gesting.: that the variation of the several coal properties was controlled by a set of- related causes. The relations apparent from the dip and strike of the first degree trend-surfaces are similar to- those which are apparent from the trend- surface residuals and'from the results' of canonical trend-surface analysis.'.. It is probable that differential subsidence controlled the areal

Jan 1, 1975

Transformations of minerals to processed mineral products fundamentally involve wholesale chemical change, and therefore have a high potential for the release of chemicals and wastes. In this regard minerals processing contrasts with downstream production operations, which involve mainly physical changes. The contrast with mining, which must take place where the minerals are found, is that mineral processing allows choices as to location, processes, fuels and reductants. These choices provide a foundation for dealing with issues of resource stewardship. This paper locates the mineral processing industry in the global perspective by quantifying the masses of major material inputs and outputs, based on current processing choices. Estimates for recycling have also been collated, revealing figures that differ surprisingly from commonly held impressions. The paper draws on a variety of current sources, mainly those available through the Internet, to rank the major transformed virgin mineral products by production, price and value. The figures demonstrate the dominance of Portland cement and steel in the global environmental impacts of mineral processing. Aluminium comes a distant third in the list, and the metals particularly associated with localised environmental impacts have relatively small global effects compared with those of the staple materials of our built environment. This global macro input/output perspective, with materials flows expressed per unit of virgin product, provides a benchmark for grasping sustainability challenges within specific operating businesses. Because of the global scope and pervasive impact of the minerals processing industry, the issue of resource stewardship is rising as a matter for public concern. There appears to be a developing view that the mining and mineral processing sector should take responsibility for these products throughout their various life cycles. However, in a future of stabilising consumption, dematerialisation and intensive recycling, the mining industry would only need to provide the top-up to a stock of recirculating materials. The question of responsibility for stewardship over SocietyÆs stock of materials remains open.

Jan 1, 2002

Using a Jarrell-Ash "Compact" direct reading spectrometer, analyses were made of a wide variety of rocks ranging from acidic to ultrabasic types. Statistical evaluation suggests that accuracies comparable with the values obtained by the rapid chemical methods used by the United States Geological Survey will be obtained.The spectrographic method involves fusion of the rock with lithium tetraborate, strontium being incorporated in the flux as the internal standard. The resulting bead is ground with graphite and pressed into a pellet. The counts obtained on two standard pellets are used to correct for instrumental drift.Background readings are made at 4109 Å and corrections for background are made to all lines. Corrections for matrix interferences, both by chemical suppression and optical enhancement, are made. The three corrections of drift, background, and matrix are incorporated into one general expression which has been programmed on magnetic cards, each element requiring a separate card. The cards are placed individually into a desk top computer (an Olivetti Programma 101), which enables true counts to be calculated from the "readout" counts, and the element concentration is then obtained from computer-printed tables by referring to the appropriate value of true counts versus concentration. These tables were prepared by making a polynomial regression analysis of the spectrographic results from 50 standard and analysed samples, a curve of best fit being chosen for each element.The regression coefficients, usually of a fourth or fifth degree equation, together with other relevant data, were fed into a large computer, programmed to print out tables of concentration versus true counts. This technique enables the results obtained to be based on mathematically-derived values rather than on hand-drawn calibration graphs, giving greater inherent accuracy. The technique has been shown to give results of good accuracy and acceptable precision suitable for many geological and geochemical exploration programmes involving the analysis of many rock samples of different types.

Jan 1, 1969

Better quality at lower cost is today's formula for remaining competitive in a world market. For an integrated steel company, high quality low cost steel production must originate before the blast furnace. In 1979, when U.S. Steel initiated a Quality Management Program throughout its steelmaking operations, efforts began at the coal, ore and flux mines. The objective was to improve the quality and reduce the variability of the critical parameters for steelmaking raw materials, to get the blast furnaces, and subsequently the melt shops, under optimum control. The general details of U.S. Steel's Quality Management Program are discussed and how it was used to promote the desired improvements in steelmaking raw materials. Some of the outstanding results obtained by the cooperative efforts between the mines and the steel plants are reported. The lessons learned by U.S. Steel were through upgrading existing operations and facilities. These principles should now be applied to new projects and the benefits of good quality management should commence from the time new projects are Commissioned.

Jan 1, 1986

By Watsford R. M S, Hutton R

Following the delineation of significant extra ore reserves during 1990, the decision was made to expand production from 350,000 tonnes of run of mine ore per year to initially 600,000 tonnes increasing to 750,000 tonnes per year. The existing plant consists of a conventional three stage crushing plant followed by a heavy medium separation plant that produces a product prior to grinding. Grinding is conducted in three stages of ball mill in series. Alternatives examined for expanding production included: aò SAG mill - ball mill circuit replacing the secondary and tertiary stages of crushing, the heavy medium plant and the existing ball mills; and, upgrading of the existing circuit configuration.

Jan 1, 1991

By D Yuen, J A. D Connolly, T V. Gerya

Recent works suggest that dehydration of subducting slab and consequent hydration and partial melting influences the dynamics of mantle wedge. Plums originating form the subducting slab due to Rayleigh-Taylor instability are responsible for heterogeneous composition of the mantle wedge. Also, occurrence of partial melt in the mantle wedge can trigger dynamic processes like exhumation of UHP rocks in intra-oceanic settings or can influence characteristics of the subduction tectonic regime. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

Dr David Dekker discussed the importance of a multidisciplinary approach to automation, the infrastructure required to support automation, and selecting the equipment for automation. Dekker stressed that automation involves a number of technologies. The mining industry is currently about part-way through the evolutionary process of achieving a fully integrated automation system. He pointed out that the final stages require parallel development of infrastructure such as mine communications. Technologies required for automation Automation systems consist of three parts: the gathering of information, the processing of that information, and taking action.

Jan 1, 1997

By Sun Yubo

A basic method for designing reasonable jig cycles for movable-screen jigs is presented in this paper. The reliability and effectiveness of the designed jig cycle was verified with tests performed on an artificial mixed material. An iron ore (12 - 100 mm) from Huashugo Iron Mine, Jiuquan Iron and Steel Company, was treated in the TJD-75 movable-screen jig using the designed jig cycle. A good result was achieved. The procedure presented here should provide a reliable technique for the design of a commercial movable-screen jig.

Jan 1, 1993

Major underground gold mine developments are not common in Australia especially when they are totally owned and hence financed by a relatively small public company. Ballarat Goldfields Limited with its Ballarat East Project is such a company. Financing a $20m underground exploratory access programme in a poor economic climate places added importance on the quality of the project. Critical factors such as ore reserves, environment, planning and the development program are of immense importance in devising and implementing a workable finance package that satisfies both the shareholder and the project's needs.

Jan 1, 1990

By J W. Harris

There are numerous detrital diamond deposits worldwide with uncertain or disputed links to known primary kimberlite/lamproite sources. In this study, we utilise 40Ar/39Ar dating of clinopyroxene inclusions in diamonds as a provenance tool applied to the mega-placer deposits along the West Coast of southern Africa. These data demonstrate that most West Coast diamonds originated known Cretaceous kimberlites on the Kaapvaal craton with negligible input from proximal Permian glacial deposits. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By D A. Aitzhanova, E Zh Omirzakova

The Republic of Kazakhstan has well developed mining and metallurgical complex. In modern conditions, when deposits of useful minerals are running thin, it is very important to find additional sources for obtaining necessary products. As our investigations showed different kinds of waste may be used for producing of different kinds of products, which are successfully applied in different branches of KazakhstanÆs economy. Analysis of ways for increasing of complex use of mineral raw materials of different deposits, widening raw mineral materials base and decreasing negative effects on the environment, are presented in this paper.

Jan 1, 2003

By Wilson T, Stone M, Mattiazzo R

The regulation of environmental management in the minerals and petroleum industries has been undergoing considerable change over the past decade. In recent years, there has been a distinct trend towards smaller government and increased environmental awareness. Current regulatory systems have generally neither responded to these trends nor effectively dealt with the demands placed on them. There is a need to develop a more effective means of providing assurance to Government and the community that its environmental objectives are being met. These means must also enable industry to have an effective environmental management process.

Jan 1, 1993

By Fitchett K

Refractory application in the major iron and steelmaking units are discussed. Mechanis- ms of refractory consumption as revealed by pre- vious studies are reviewed and current practice is evaluated. Deficiencies in refractories now in use are noted and some lines of development are indicated. The iron and steelmaking units discussed are generally restricted to those subject to slagging, structural change or erosion at steel or iron making temperatures, and include the Blast Furnace, Hot Blast Stoves, Hot Metal Ladles, Basic Oxygen Furnaces, Continuous Cast- ing Units and Steel Teeming Ladles.

Jan 1, 1972

Offshore petroleum development involves massive capital expenditure and financing demands, with the main participants being large international oil companies and State owned enterprises. Types of project oriented financing include take-or-pay contracts, throughput agreements, and production payment financing. The main project finance credit aspects are revenues, investment budgets and cost over- runs, reservoir, political and other risks and special problems such as weather and corrosion in the North Sea. A variety of documents is required and a mix of equity, export credit and Euro-market financing will typically be included in the financing.

Jan 1, 1983

There are a number of methodologies which can be used for the preparation of environ- mental impact statements. Selection of a method depends upon the type of project and the environmental characteristics of the area where it is to be built. Most methods are satisfactory for assessing impacts on the physical environment but less so for the biological. Major problems may arise in deal ing with sociological issues because value judgements are involved. Several methods of approaching problems of this nature have been tried with some limited success.

Jan 1, 1976

The Broken Hill orebodies have 'traditionally been mined by cut and fill trethods. In the mid-1950's New Broken Hill Consolidated Limited experimented with sublevel longhole open stoping but did not pursue the method due to inefficient loading and poor fragmentation. The introduction of longhole open stoping in 1968 was a radical change and was necessary to enable the profitable extraction of lower grade orebodies and this method is now used for 55% of the production from The Zinc Corporation, Limited and New Broken Hill Consolidated Limited mines.

Jan 1, 1982