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I am very grateful to have the honor of delivering this Key- note Speech to all of you here today, to the Chairman Mr Cope- man, and to all the organisers. As you heard, I was mainly involved for a very long time in the purchase of iron and steel raw materials for Nippon Steel Corporation. Today, however, I would like to talk to you about a much wider issue, namely, how the Japanese steel industry is going to change towards the 21st Century, and what will be the main technical innovations and trends behind those changes. I will also mention the effect that the changes are likely to have on the procurement of raw Materials.

Jan 1, 1988

By Johnson CR, Wilkie G

The aim of the study was to use quantitative mineralogical measurements to predict the processing characteristics of an ore. Samples were taken from a wide range of concentrators processing ores of lead, zinc, copper and nickel. QEM'SEM was used to measure the characteristics of the ore feeding the plant. Concentrate product samples, together with plant operating data were used to give concentrate grade, recovery and grind size information. It was found that the mineralogical measurements correlated well with the metallurgical parameters indicating that these techniques will be very useful for making predictions in feasibility studies and simple plant optimization.

Jan 1, 1989

By Chavant G, Begis D, Gunther J

To study the ventilation of a mine (improve on the existing situation, examine extension projects) the calculation program used must take into account all the resistance values in the branches of the network. These resistance values are generally determined by measurements, which are accurate to a greater or lesser extent. In order to arrive by calculation at the flowrates measured :n the mine at a given moment, the resistance values have tto be adjusted experimentally. This manual operation is lengthy and delicate.

Jan 1, 1988

By Miller M. J, Bauer J. C

The continuous copper drossing process operated at Port Pine since 1962 has had limited copper removal capacity as determined by a maximum tolerable Cu/S ratio in feed and the level of sulphur in blast furnace bullion. Recent process development has been to overcome these limitations to meet increased copper throughput requirements. A sulphur addition system was developed and installed in August 1987. The system has capacity to increase sulphur input by over 150%, meeting the increased copper capacity requirement and also allowing independence from the upstream process for sulphur supply. Developments in process understanding have been applied within the limitations of the existing furnace design with a 10% increase in the maximum tolerable Cu/S ratio.

Jan 1, 1989

The task of designing stable high walls and spoil piles in strip coal mines, and stable openings with controlled roofs and floors in underground collieries - within the constraints normally imposed by economics - depends upon a reliable assessment of rock mass strengths and rock mass reactions under a variety of stress conditions. Of the geological factors influencing internal friction and cohesion within rock masses, many may be determined qualitatively or empirically from bore-hole evidence. Rock types, descriptions and properties of intact rocks, location of boundaries, limits and degrees of weathering, potential for slaking or decomposition of rocks when exposed, bedding characteristics, the nature of rock anisotropy and the likely effects of water on rock mass properties can be assessed from bore- hole data. Discontinuities, whether they be major such as faults and dykes, or minor such as joints and fractures, present a greater problem, and in most instances the mine geologist must resort to additional techniques to describe or predict their occurrence, nature, frequency, intensity or physical properties. Information on ground water and seam gas is available from bore-holes within certain levels of reliability.

Jan 1, 1977

By Lumley G. I, Hayes H

Non-intrusive methods for the reliable determination of dragline bucket and rigging performance have been achieved using physical modelling. Modelling offers a logical first step towards developing mathematical simulation models. The process of physical modelling has been applied successfully to predict dragline bucket performance and capacity as well as to demonstrate the effect of varying dump rope length on performance. ACIRL's Surface Miming Group has used physical modelling to carry out dragline bucket sizing for a new high productivity bucket and compared performance with Throng Coal's existing dragline bucket. The predicted bucket performance has since been confirmed in the field using dragline monitoring techniques.

Jan 1, 1992

By Ramsden AR

The ability of the scanning electron microprobe to provide non-destructive qualitative and quantitative mineralogical analysis at the micrometre scale makes it a very versatile tool for the mineralogical characterisation of ore deposits and their host rocks. With the trend towards exploitation of large tonnage low grade depositsnd precious metals at the parts per million level it is becoming increasingly important to have full mineralogical characterisation and knowledge of the mineralogical residence of the valuable elements to assist formulation of a cost-effective exploration program and obtain optimum recovery in the case of exploitation. Mineralogical applications include

Jan 1, 1989

By Just G. D

Performance of draglines in large scale overburden stripping operations is critical to the efficiency of a major section of the Australian Coal Mining Industry. Optimisation of dragline productivity requires an understanding of a range of operating conditions and constraints. One of the least understood of these operations is the process of bucket filling and how this may vary with respect to variable operating conditions.Studies conducted at The University of Queensland over a number of years into this problem have enabled the mechanics of excavating to be assessed for different types of fragmented rock. In relation to bucket filling, factors such as fill volume, digging time and energy consumption have been found to be significant factors in optimising bucket design, bucket rigging and operational techniques.

Jan 1, 1992

By Milner E. F

Thallium is largely volatilized during sintering in the conventional sinter/blast furnace production of lead. The new direct oxygen smelting processes will force the thallium into the bullion, necessitating a means of removal to avoid contamination of the refined lead. Pilot plant testwork demonstrated that thallium was efficiently removed from lead bullion by treatment with molten zinc chloride. The spent zinc chloride salt was treated in the laboratory to recover lead sulphate, a zinc chloride solution, and a thallous chloride salt containing over 80% thallium. Cominco is installing this thallium process as part of its Trail Lead Smelter Modernization Program which will commission a QSL bath smelter in late 1989.

Jan 1, 1989

The, Ore-bodies.-The ore-bodies of the North mine, North Broken Hill Ltd.; consist of two lenses, connected by a narrow neck of mineralized country. They pitch at an angle of 40° in an easterly direction and dip north at 60° to the horizontal. The southern ore-body, on a horizontal plane, has a total maximum length of 800 feet and in one place attains a width of 230 feet, whilst the northern orebody has a maximum'length of 600 feet and a maximum width of 80 feet.

Jan 1, 1940

By D Williams

Recent advances in global positioning systems (GPS), machine guidance technology and telemetry allow an unprecedented level of control of surface mining operations. GPS technology can now locate the bucket of a shovel or the blade of a dozer within 50 mm. Some of the outcomes possible are: precise selective mining û even when the ore is visually indistinguishable from waste; tracking grade and tonnage of every ore parcel through the mine; real time productivity monitoring; detailed post accident safety analysis; and tracking the movements of every piece of equipment. This paper will consider the contribution that GPS based machine control systems can make to ensuring that surface mining projects deliver the outcomes promised in the feasibility studies. Case studies of installations are presented.

Jan 1, 2003

Drill and blast operations account for 12 - 15 per cent of total mining costs. This paper looks at a comparison between electronic detonators and non-electric detonators, focusing on the cost benefits associated with the high precision of the timing sequences of electronic detonators. An analysis of the total mining costs was made on two main case studies; one on a quarry in South Australia (Martin, 2007) and the other on a project undertaken at Sunrise Dam (Vaughan et al, 2007). The criteria used in the analysis included; the resulting fragmentation, a vibration analysis, crusher throughput and productivity analysis such as excavator cycle times, dig rates of the excavator and bucket fill factor. The results indicate that there were consistent production improvements and hence reductions in total mining costs attributed to the use of electric detonators. An increase in the degree of fragmentation gives lower crushing costs as more material passes through as undersize. This reduces truck delay time at the crusher, which in turn gives higher truck and shovels productivity as well as higher dig rates for the excavators.

Jan 1, 2008

By Yokozawa K, Yamamoto T, Kameoka Y

Japan Construction Method and Machinery Research Institute has been conducting various field surveys of tunnel works and other excavation works, and the cost and efficiency of these two excavation methods have been studied. Based on these data, the costs of blasting excavation and mechanical excavation represented by roadheaders were calculated. The costs were calculated and compared for rocks of various hardness. When the total construction cost is considered, the degree of overbreak becomes one of the most influencial factors, because the overbreak area must be filled up with expensive shotcrete in NATM. So, in the next step, the relation between the excavation costs considering overbreak and the rock hardness was studied using the data on overbreak obtained by the field survey.

Jan 1, 1987

By Smit J. G

Following an increase in the number of methane ignitions in South African coal mines a new ventilation system was developed. The "Hydravert" system conceived in late 1979 for use in low seam coal mines, where the bord and pillar method of working is used, has been extensively developed to include applications for mining seams up to 4.5 metres high. A brief history of the development is supplied including some of the pitfalls encountered in the hydraulic equipment design and selection.

Jan 1, 1988

Urban railway systems need high invest- ments, especially if their routes and stations have to be placed in the subsurface. In the FRG the construction and equipment cost of urban underground railway systems are in the range of 60 to 100 Mill DM per km tunnel. For this reason, track sections on the surface and on elevated structures are used as far as that is possible. Considering whole systems, the costs are in a range from to 45 Mill DM per km length for a metro system with about 80 % of its tracks and stations in tunnels and from 20 to 25 Mill DM per km for a light railway system with about 25 % subsurface infra= structure. The amount of route lengths in tunnels depends on the size of a city, the situation regarding above ground structure and free space on the surface, the level of service quality which has to be achieved with the railway system etc. Despite of the urgent needs to improve the transport conditions there very often arise doubts if an urban railway system is really necessary and can be justified in an economic sense. The experience from many cities around the world shows, that there arise a lot of benefits from urban railway systems, especially with larger sections placed under- ground. They are to be found in the interests of the operator (f.e. operating costs), the user (travel time, quality of service etc.) and regarding social aspects (environmental protection, accidents, consumption of energy Etc.).

Jan 1, 1987

The mining production rate of two million tonnes per annum at Olympic Dam required greater servicing capacity than was available with the existing Whenan Shaft. To increase servicing capability a Service Decline was constructed from June 1986 to June 1987 extending 2000 m from the surface and linking up with inclining development from the existing Whenan Shaft workings. The decline was used for access of all men and materials during the construction phase of the ore handling system. During production, most mine servicing will be via the decline with hoisting of rock through Whenan Shaft.

Jan 1, 1988

By Carter LC

Following the perception by the Groote Eylandt Mining Company of a need to further beneficiate a fines product, and preliminary metallurgical testing to demonstrate the feasibility of such beneficiation, a comparison was made of the various configurations of cyclonic heavy medium separators available. This comparison consisted of (i) a pilot plant test in which a dynawhirlpool (DWP) and a pump fed cyclone were compared, and (ii) a survey of operating plants using the systems under consideration. Little metallurgical difference was found-between the different systems. The gravity fed cyclone configuration was finally chosen based on a particular need to minimise degradation of ore and on a desire, in so isolated a location, to use established and locally supported technology.

Jan 1, 1987

By Li T

Mining of the southern 1900 copper Orebody presented a challenge due to the complex geology, geometry and simultaneous extraction of the nearby lead/zinc/silver orebody. An integrated and co-operative approach was adopted, involving geology, geomechanics, mine planning and production personnel. Successful extraction of the first 1900 Orebody stope, T496, together with the extraction of the first two lead/zinc/silver panel stopes in the immediate hangingwall of the 1900 Orebody stope was achieved as a result of this approach.

Jan 1, 1995

By Noreen D

At Bougainville Copper Limited comparison testwork was conducted between "horizontal" cycloning and conventional vertical cycloning. Horizontal cycloning reduces circulating load and allows increased ball mill throughput. Cyclone efficiency is the same or better as a result of the reduction of fines short-circuiting to the underflow. Operationally, horizontal cyclones are less likely to suffer from blocked spigots and high cyclone feed pump sump levels. Cyclone feed pumping power is reduced. High horizontal cyclone underflow density provides the option to optimise grind by manipulating water addition to the ball mill feed.

Jan 1, 1988

By El-Ansary M

Estimation of in-situ resources and recoverable ore reserves for the Boddington Gold Mine feasibility study was done by applying an essentially "classical" ore reserve method. This relied completely on customized graphics-based computer software requiring close co-operation and interaction between geologists and mining engineers. All geological and mining outlines were interpreted and digitized manually. Classification of selectively mineable reserves into ore, marginal and waste categories was done using a method involving convolution, devised by Dr S Carras of the Systems Research Institute of Australia, and Mr R Hooper of Kinhill Stearns. The estimation process was complicated by the frequently conflicting requirements of the various joint venture partners. The resulting ore reserve figures therefore satisfied only the most general expectations of each partner.

Jan 1, 1987