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Spectacular high-temperature hot springs (æblack smokersÆ) on the deep ocean floor are producing economic concentrations of base and precious metals. Mining these seafloor massive sulfide (SMS) deposits is about to become a reality in 2010, subject to the timely issuance of permits. Three Australia-based private companies and two government agencies inJapan and Korea have exploration licenses or applications covering vast areas of the seabed in the western Pacific targeting SMS deposits. Technological and financial challenges for recovery of seafloor sulfide deposits are being met and mining these may be less environmentally deleterious than mining on land. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

Taiwan is situated between Ryukyu and the Philippines with 35,960 sq. km of area, being slightly larger than Belgium It has roughly a spindle-shaped outline with a longitudinal axis extending in a roughly north-south direction. Geologically, Taiwan is extremely complex in terms of its tectonic setting in the convergence zone between the Asian continent and the Philippine Sea Plate. To the east of Taiwan, the Philippine Sea Plate subducts beneath the Ryukyu island arc, and to the south of Taiwan the Philippine Sea Plate overrides the Asian plate along the Manila Trench. Taiwan, therefore, occupies an unstable region between these two well-defined subduction systems of opposite polarity (see the following block diagram).

Jan 1, 1987

Unprecedented political, economic, and social change throughout the world will have an increasingly profound effect on the dynamics of the world's mining industry. Analysis of the early financial trends in this development (statistics on exploration expenditure, and investment flows) gives some insight into the magnitude of structural change and its implications for established mining economics and companies.Increasing confidence in the stability of many third world and developing countries is attracting exploration and investment capital that had previously been largely directed to established mining economies in North America, Australia, Europe and Southern Africa. Some of the projects requiring capital and technology in the CIS, Africa and Latin America are technically very attractive. The end of the 'cold war' and the influence of the IMF is gradually changing their risk profile for mining investment.

Jan 1, 1993

By N Ozawa, R Kaneko, M Arimit

The Mitsubishi Higashitani limestone mine is a ten million tonne per annum operation located near the city of Kitakyushu on JapanÆs western island of Kyushu. Higashitani is one of the largest limestone mines in Japan and accounts for about five per cent of national production. Blasting practices at the Higashitani mine involve the use of bagged ANFO, dynamite primers and non-electric detonators. Regulations in Japan prohibit the use of site mixed bulk explosives. Blast size is usually around 17 000 tonnes with 20 holes in a single row, two or three blasts are fired per day at a powder factor of between 0.25 and 0.32 kg/m3. As part of a program looking at oversize reduction Mitsubishi, Asahi and Orica agreed to conduct a joint project at the Higashitani mine to investigate the relationship between the powder factor and fragmentation. The first stage of the project was to benchmark the current blasting performance. Five blasts were monitored in each of the 210 (hard rock) and 220 (soft rock) areas of the mine. OricaÆs Powersieve« software was used to measure fragmentation and total rock breaker hours were also recorded for each blast. OricaÆs computer blasting simulation model Sabrex« was used to prepare revised blast designs with a higher powder factor and predict their performance. The performance of these blasts was monitored using the same methods.

Jan 1, 2004

Martin Mining and Tunnelling Pty Ltd is a mining contractor with offices in Kalgoorlie, WA, Australia and Timmins, Ontario, Canada.Martin Mining and Tunnelling Pty Ltd offers services in mine contracting which include shaft raising, raise enlarging, excavation of rock passes and ventilating systems. It also offers the mining industry a unique mining method using the Alimak raise climber system.The Alimak raise climber system may be utilised in various types of orebodies, as the system is flexible to change. Sloping widths, drill hole patterns and changes in dip can all be accommodated with this method.This system allows for a highly productive, cost-efficient alternative to conventional longholing methods. This paper will focus on various aspects of the Alimak system which inherently make it a safe, viable method of ore extraction.

Jan 1, 1993

The paper re-visits an old and proven concept of winzing, a method widely used in the past to gather exploration data for accurate definition of the orebody. It is proposed to use a mobile Supersucker (a giant vacuum cleaner also known as vacuum lift), to carry out winzing activities underground. A brief description of conventional underground winzing used in the past is provided, together with a discussion on other underground bulk exploration methods used in Australia to date. Historical background, principles of the proposed system, Supersucker construction details and productivities, and benefits and advantages of the proposed system in comparison with other exploration methods, are outlined. Other relevant applications of the mobile Supersucker, including surface winzing, are also briefly discussed in the paper. With a view of using the mobile Supersucker to recover all broken ore stocks underground, included are also results of floor sampling conducted recently in the in-stope decline excavated in a coarse gold type, high-grade orebody.

Jan 1, 2002

The types of risk to mining projects using environmental protection as justification are examined. In Australia, Governments, whether Federal or State, enforce environmental legislation. The way they do This has an impact on the risk to a project. This is discussed and examples are taken from the Northern Territory uranium industry. Special reference is made to mine closures where the roles are not yet entrenched.

Jan 1, 1994

The difficulty of successfully imple menting a landscape policy is almost incom- prehensible. Landscape design is recognised as an essential component in the integration of engineering and architectural projects into the landscape, but the factors which prevent the achievement of a successful result are rarely recognised or assessed. In many cases these prohibiting factors are due to a lack of understanding of the effect of major planning decisions on the existing landscape, the importance of the landscape plan and the significance of appro- priate specified techniques to prevent un- necessary damage and to ensure retention of existing vegetation in a healthy condition. The role of the landscape architect in incorporating new land uses into the landscape provides the background against which factors which inhibit policy achievement can be con- sidered.

Jan 1, 1976

By K H. Esbensen

During the next five years Denmark will implement a significant reduction in the national CO2 emissions to fulfil the Kyoto Protocol. The energy sector is central for achieving this goal and extensive use of renewable energy is the most important single factor contributing to reduce emissions of greenhouse gases. DenmarkÆs renewable energy sources comprise wind energy and biomass. Wood chips and straw are the dominant type of biomass in Denmark. More than 500 000 tons of wood chips are used annually, currently with rapidly growth prospects. This contribution focuses on sampling of wood chips.

Jan 1, 2005

By Vassiliev P

Cut-off optimisation, based on the work of Lane (1988), can be used to maximise the NPV (Net Present Value) of a mine by the judicious manipulation of cut-offs and the use of stockpiles. Apart from maximising NPV, cut-off optimisation will ver

Jan 1, 1998

Ranger Uranium Mines (RUM) operates an open cut located in the Top End of the North- ern Territory. Strict environmental controls govern all operations and the water management requirements have the greatest impact on mine planning. The two main goals of planning are to provide mill feed and to mine sufficient suitable quality waste rock for ongoing con- struction of the tailings dam. Early planning concentrated on staged development of the pit to provide access to as much ore as possible for a given amount of development. All waste was considered to be suitable construction material. Grade control of crusher feed was the main problem in planning, as wide vari- ations occur in ore grade over relatively short distances. Water management for the site ope- rates a no release' system for contaminated waters. Design storage has proven inadequate, and the open cut has been used as the extra storage. As construction of future stages of the tailings dam requires non-mineralised rock materials which meet specific quality criteria, the mine has had to re-examine long term plan- ning and pit development strategies. This has entailed the collection of much data not re- quired under normal mining conditions, such as the assaying of waste drill core. The overall impact on mine planning of the environmental regulations has been to alter the philosophy of earlier planning, making it necessary to create a new strategy for pit development with

Jan 1, 1984

New Caledonia is a major metallogenic unit of the south-western Pacific Rim. Its mineral production is of world significance and it has an unusually well diversified mining history. New Caledonia's main metallogenetic potential is, however, associated with its unique ophiolitic complex and its important mineral- izations of nickel, chrome, cobalt and iron. Gold has been found in all the four basic tectonic elements of New Caledonia: the Central Massif, the West Coast basalts, the ophiolitic complex and the Caledonian North. Some analogies are attempted. Only the Caledonian North has supported mining operations (213 kg Au). More recently tenuous gold indications have been found within the ophiolitic complex, possibly associated with Oligocene plutonism.

Jan 1, 1987

By Takasaki Y, Ohzeki S, Hotta H

TO measure high temperature properties of blast furnace burdens ( the change of gas permeability accompanied by contraction, soft- ening and melting ) which govern the gas flow and its distribution, a series of experiments were carried out under simulated blast furnace conditions, using sinter, acid pellets and self -fluxing pellets. 1) The high temperature properties are affected by the ore's reducibility ( up to 1000 -1200¦C ), and the composition, and volume of gangue before reduction. Generally, the burde- ns with high basicity ( Ca0/Si02 ), high reduc- ibility and low volume of gangue have good high temperature properties. Good high temperature properties are : a high temperature at which the gas permeability rapidly decreases, a high melting point and a low maximum pressure drop. 2) Using acid pellets, slow-down of red- uction rate occurs around 1000¦C because the pellet forms a dense metallic shell, while its slag core, resulting from a FeO, Si02 and A1203 reaction, has a lower melting point. 3) The addition of MgO sources improves high temperature properties both of sinter and Pellets.

Jan 1, 1980

By Pietrobon M. C, Ralston J, Smart St C R

In an on-going study of the chemistry of base metal sulphide flotation, the effect of the inclusion of cyanide in the reagents suite has been studied, with special reference to ore from Pasminco Mining's Elura mine. Cyanide has been variously described as an iron sulphide depressant, a preventor of sphalerite activation and as an activator of galena. In the case described here, the cyanide appeared to act as an enhancer of the galena flotation performance, raising the lead recoveries by 25 per cent but leaving the sphalerite and pyrite responses unaffected. The lead rougher flotation performance with and without cyanide was investigated over a wide range of redox potentials (0 mV to 400 mV SHE). In all cases, the inclusion of the cyanide brought about an increase in the galena recovery and was responsible for a faster rate of galena flotation during the initial stages of the beneficiation. A surface characterisation study (XPS) of the lead flotation stage, with and without cyanide, indicated that the reagent interacted specifically with the galena and pyrite minerals. It was possible to correlate the surface absorption of the cyanide on the lead and iron sulphides with improvements to the flotation performance using the combination of surface spectroscopy and laboratory flotation Testwork.

Jan 1, 1991

The resistance of lead to chemical attack and the ease of its fabrication has made it one of the most useful of the metals available to the chemical engineer and the electrometallurgist. It has proved to be of particular value in the manufacture of sulphuric acid, and since the conversion of the sulphur of pyritic ores into sulphuric acid is becoming the duty of the metallurgist, the corrosion resistance of this metal will be a matter of considerable interest to him from the standpoints of both producer and user. He realises that there is little to be gained in carrying the process of purification past the ordinary economic limit if little or nothing is to be added to its corrosion resistance, and he as user would not be willing to pay a premium for such purification if it can be shown that its reputed value has no scientific foundation.The metallurgist is well acquainted with the trouble and expense of meeting demands which have nothing torecommend them but prejudice and fancy. The valuable anti-corrosive properties of lead are very commonly ascribed to its forming insoluble compounds with the acids sulphuric, hydrochloric, carbonic, etc. If we trusted superficial visual evidence alone, such a view would receive strong support, but in the light of what we know of the mechanism of corrosion we must attribute its resistance to other factors much less obvious to casual inspection. Certainly there may be some mechanical obstruction set up to diffusion of the liquids towards the surface of the metal.

Jan 1, 1932

By Dunlop JSF

A description of general mining proced- ures and tyre maintenance practice is given with particular reference to tyre mainten- ance facilities and record keeping at Groote Eylandt. Experience with tyre wear on Wabco 85C rear dump trucks is then outlined, concen- trating on wheel camber, wheel alignment, truck speed, tyre pressure, loading and haul road design. T T.1TUnilhTPTTnAT The Groote Eylandt Mining Company Pty. Limited mines and beneficiates sedimentary manganese ores from a series of orebodies occurring in the western part of the island. The island is one of a group on the western side of the Gulf of Carpentaria, about 50 kilometres from the Arnhem Land coast and about 650 kilometres from Darwin. Whilst capacity of the mine is presently 2.3 mil- lion tonnes of product per annum, current production has been reduced to just more than half this figure, due to a general mar- ket recession.

Jan 1, 1982

By P C. Pistorius

Previous mineralogical investigation of all effluent flotation streams of Mimosa mine (Zimbabwe) indicated that appreciable amounts of liberated platinum-group minerals (PGMs) of the Pt-Pd-Bi-Te class are not recovered û despite electrochemical measurements showing interaction between xanthate and such minerals. In this work, the flotation recovery of synthetically prepared Pd-Bi-Te was compared with that of chalcopyrite (a typical fast-floating mineral) and pyrrhotite (a typical slow-floating mineral), with microflotation tests. These indicated Pd-Bi-Te to be a fast-floater with flotation rates exceeding that of chalcopyrite. Predicted flotation rate constants (from the Ralston model) were significantly lower for small particles (with diameters similar to those lost to the effluent streams) compared with those of particle with intermediate sizes. This supports the suggestion that losses to effluent streams are caused by particle size effects.

Jan 1, 2005

By Valery W, Morrell S, Loughlin P, O&apos

Traditionally, blasts in mining operations are designed to prepare the in situ rock mass for excavation and transport without much consideration being given to the downstream comminution processes. Blasting is in fact the first step in a chain

Jan 1, 1998

By X Y. Ma, X G. Tian, P F. Zhang, T B. Zhao, Z H. Li, Z Y. Fu

This study analysed the fracture characteristics and movement process of goaf roofs under the condition of gangue backfilled mining, based on the engineering conditions of Tangshan Mine F5001 gangue backfilled working face. The inclined borehole detection method is adopted to conduct long-term and fixed-point detection of the roof stability. The distribution characteristics of mining-induced cracks in the roof are described quantitatively based on the crack density, and a similar model test method is used to assist the analysis of the roof movement under the control of gangue backfilled mining using stress sensors and digital speckle deformation field monitoring. The results show that under the condition of gangue backfilled mining, structural cracks in the roof typically appear at the boundary of rock strata. The appearance of cracks is related to the rock strata where they are located. Structural cracks appear in the form of single cracks ahead of the working face and develop into structural cracks in the goaf. The roof movement of the coal seam develops in five stages: fracture incubation, crack extension in advance, dense fracture development, steady fracture expansion, and roof stability. Separation forms the primary component of the roof subsidence, accounting for more than half of the subsidence value. The separation generally extends over a long distance along the strike, and vertical crack-intensive areas appear in the roof above the cut-off and stop line. The findings of this study provide a theoretical basis to support designs of backfilled mining and upgrading of hydraulic supports in working faces.

Nov 29, 2022

By J Lim, M Powell, P J. Scales

The current philosophy employed in the design of mineral processing plants effectively involves bolting together segmented unit operations both chosen and optimised from a product-centric perspective. In this context, integration of water saving technologies at an overall plant level becomes difficult and often only local water efficiency improvements are feasible. In general only limited benefit can be obtained from such add-on solutions. It is therefore proposed that to obtain significant savings in water consumption and reductions in the volume of discharged contaminated water in the mining process, the entire process along the mining and mineral processing chain should be addressed This paper explores aspects of the processes that may be modified to provide an integrated and combined step change saving in water consumption. It is also apparent from this study that taking a more holistic view of the process can provide significant benefits in energy savings and total cost of production, providing the potential of a substantial win-win outcome.

Jan 1, 2009