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By Gabriella Mendez

Worthy of note in Miss Bailey's paper are her comments on the attitudes of mining companies and their managers where women were employed, she says, "..another possible pitfall is reverse discrimination where in an effort to avoid being branded as having shown a person favouritism, supervisors end up treating the person in a manner much less than they deserve. This is manifested in denying an employee such things as challenging work, educational opportunities, promotions, or in the case of staff, fair merit increases." and further she says, "It has been observed that the treatment of women in non-traditional roles such as mining is different than for men in the same environment. There are people who treat women worse and some who treat them better simply because they are of the other sex." These statements may sound unjustified to today's audience, and whilst we need to credit pioneering women with having tolerated, understood and worked towards improving the mining culture, the move towards total inclusion of women in the workplace is still growing.

Jan 1, 1995

Until 1937, the mining of ore was carried out by conventional methods, using pneumatic drills and standard drill steel. The adoption of the diamond drill, formerly used for exploration work, for blast hole drilling in stopes, was first developed by Noranda Mines Limited, Noranda, Quebec, although it had been used previously in Northern Ontario and Western United States, to remove weak pillars and ore remnants left by conventional methods. Previous to the adoption of the diamond drill method at Noranda, a sub-level benching system of stoping was used. Sub-levels were driven at 35 ft. intervals and the benches drilled off by pneumatic drills using sectional steel. Results were very satisfactory, in sulphide ore, where the drilling was comparatively easy, but in the harder rhyolitestopes the footage drilled per machine-shift was only half of that obtained in the sulphide stopes, and owing to the high gauge loss, there was often difficulty in drilling holes to the required depth. This led to trials with the diamond drill for this type of work. While the cost per foot was more than with sectional steel, an appreciable saving in development work could be made by increasing the sublevel interval from 35 ft. to 60 ft., and stope widths from 60 to 100 ft. This saving, together with the increase in blasting efficiency, resulted in a substantial reduction in overall costs.CONDITIONS FOR SUCCESSFUL APPLICATIONWhile long diamond drill blast-hole mining has widespread application, there are certain conditions which appear to be desirable, if not absolutely necessary, for its successful use.

Jan 1, 1946

Record quantities of slag were produced in 1974. Slag usage in this year amounted to 8.5 mega tonnes for granulated blast furnace slag and 7.7 mega tonnes for crushed blast furnace and L.D. slags. Granulated blast furnace slag is mainly used as a hydraulic bonding material in the manufacture of cement and in road construction. These applications give a fuel saving and reduce processing costs. Crushed blast furnace and L.D. slags find application as a substitute for natural aggregates in road construction and in the production of concrete. There is no doubt of ttie interest to utilise to the maximum all the slag produced by the steelmaking industry, thus preventing the build up of slag heaps detrimental to the environment and favouring the disposal of the heaps formed in the past. World wide efforts are being made to achieve this objective.

Jan 1, 1979

Staff turnover percentages on projects in the minerals sector are at levels that would not be accepted in business less than five years ago. While this is being driven in part by the shortage in skills to service the industry there are underlying factors, beyond the increases in remuneration, adding to the turnover. Having identified the five major reasons why people do not stay, this paper confirms that leaders and the various styles are common to all companies. The paper comments briefly on these major reasons and suggests the problem is firmly with management. It also offers possible remedies to reduce the attrition and therefore improve the opportunities for a quality project evaluation.

Jan 1, 2009

By Churchill J

A suite of software programs has been written to provide the field engineer or geologist with the capability to collect and store data directly into small, portable handheld computers. This allows the engineer and geologist to collect data in a more efficient manner as the data is collected in sequence and is verified at the time. Typical applications for this software include geological and geophysical logging, trucking surveys, mine surveying, condition monitoring, ventilation surveys and maintenance systems. The software allows the user to construct his own electronic notebook by structuring data input to the computer in a similar manner as is now done on pre-printed forms. The user can store all valid entry codes or numeric ranges in a dictionary and all data inputs made are validated against this dictionary. Once constructed the user may call the electronic data sheet into the unit and collect data which will be stored into the unit which has the memory capacity to record data for up to periods of 60 hours. The data can then be automatically transferred to mini/microcomputers for immediate analysis and report generation. The software may be used on a variety of handheld computers.However the generally rugged environments found in the mining industry limit the choices. In particular the authors have selected a unit weighing a little over one kilogram, which is rugged enough to fall off an underground survey vehicle, and survive when accidentally immersed in water,without losing data. This paper describes the software developments in detail. The project development work to produce this system has been funded by a grant from the Australian Mineral Industries Research Association and is supported by a number of large Australian mining companies.

Jan 1, 1986

A mining joint venture presents a real management challenge to achieve harmony with the other participants in the successful development and operation of a mine. This can best be facilitated by a detailed agreement and guided by a set of joint venture principles which recognise the differences of the interests of the parties and seek to establish sound business and personal principles by which differences not anticipated in the agreement might be resolved. The major and minor co-venturers can and do present potential difficulties to one another. This paper, one of the pair in the joint venture panel discussion session, predominately presents the minor's viewpoint. Usually commercial matters such as project finance, areas of interest, divestment, pre-emptive rights and decision-making can be adequately covered in the agreement. However, when the parties disagree and have difficulty in resolving their differences, the joint venture principles should be used to advantage to resolve relationship difficulties.

Jan 1, 1997

By D R. van der Meulen, P Ande, D J. Lunt

Pressure hydrometallurgy is becoming an increasingly common unit operation in the treatment of gold and base metal ores and concentrates. The design of an adequate and appropriate pilot-scale testwork program is, therefore, essential in order to minimise the risks associated with developing a project in which autoclaves form a key part of the operation. This paper identifies the approaches that have been taken in the piloting of oxidative and pressure acid leach operations. Particular emphasis is placed on the determination of scale-up ratios between the pilot and commercial plants and the pilot-plant run durations. The issues, both metallurgical and project-specific, that can impact these key parameters are reviewed.

Jan 1, 2004

The short review of hydrogeologic conditions in the three Polish coal basins have been presented as the background for the prevention measures against water inrushes being underta- ken in coal mines. The Polish mine safety regulations concerning water inrush prevention have been discussed, namely: - classification of sources of the potential water inrushes, - levels of water inrush risk and conditions of mining operation in the mines facing particular risk levels, - determination of the -di.mens.ons.of protecting pillars to prevent water inrush to mines, protection of surface water reservoirs and their earth embankments in regions submitted to mining deformations. Three examples of coal mining being carried out under water bodies have been presented.

Jan 1, 1988

A wide variety of process streams are sampled for grade control in the mining industry. However, in many instances the overall precision of the resultant analyses is inadequate for the intended purpose, ie grade control and optimisation of resource utilisation. Consequently, special attention needs to be given to the sampling, sample preparation and analysis procedures in place to ensure that meaningful grade control decisions can be made based on the analyses generated. For example, it is virtually impossible to control a process to within, say, ¦0.2 per cent if the overall precision of the analyses is no better than 0.5 per cent. Hence, precision targets appropriate for the task need to be established and the overall precision achieved in practice monitored and controlled on an ongoing basis.

Jan 1, 2008

Mines in the future deliver a paradigm shift in the way mining, material handling and processing are performed, unlocking significant value through production efficiency, flexibility and lower costs and enabling substantial safety and environmental benefits (V Schweikart). Mines in the future are highly productive, with low production costs and are significantly safer. They operate with a skeleton crew and use intelligent systems that fuse information from field instrumentation and other sources to generate the most efficient operating environment. Automated systems are seamlessly integrated across the mine and across the corporate enterprise. Geological models, long-term and short-term plans create optimised production schedules, suitably generated by the mine simulator. Production schedules are shared with the operations management system for deployment mainly by remotely operated and autonomous equipment. As the schedule is implemented, information is collected and shared with various plans, schedules, models and optimisation programs. This production environment is managed in real time from a æCentral Operations CentreÆ and it is visible across the business providing fast and accurate information about productivity, machine condition and environmental conditions. Central Operations Centres also house teams of subject matter experts that monitor and manage the mines and are able to communicate directly with the skeleton crew in the field. Constraints across the production line are displayed and managed appropriately from this location to maximise throughput. Maintenance is interactive and predictive. Reliability specialists in Central Operations Centres monitor the status of machinery and equipment and adjust maintenance plans and strategies to suit. Mining businesses rely heavily on knowledge workers û people with considerable knowledge and learning û and by manual workers. This new knowledge workforce is a team of associates rather than of bosses and subordinates. Field experts become leaders with tremendous autonomy regarding their work. The former line hierarchy becomes a support structure, intervening only in extreme emergencies; instead of giving orders, they are now removing barriers, expediting resources, conducting studies and acting as consultants.

Jan 1, 2009

Teleoperation is one method by which an operator can remotely control and monitor a vehicle. The operator monitors the status and progress of the remote vehicle by watching the video transmitted from one or more cameras which are mounted on the vehicle. In the case of an LHD, it will be fitted with three cameras. For a twin-boom Jumbo, four cameras are mounted on the drill, three of which will have remote pan, tilt, 15x zoom, focus and lens cleaning controls. The advantage of teleoperation is that an operator can stand in the drive and send the remote vehicle around a corner, completely out of sight and still clearly see what is happening. This means that an LHD returns with a full bucket and a Jumbo can be operated from a safe distance. Standing in the drive teleoperating vehicles, exposes the operator to passing traffic including the remote vehicle. There are two solutions to this problem. One is to equip the operator with a Nautilus æBuddyÆ jacket which will help to protect them from all vehicles. The other is to move the operator into a safe room or area, away from the fumes, the noise and the traffic. In this comfortable, less stressful environment, the operator will be more productive and less likely to accidentally damage the vehicle. The operatorÆs æsafeÆ room does not have to be a formal control room, it can be any area which has AC or DC power available and is large enough to contain a chair and a 1.5 m x 0.75 m table. The æsafeÆ room can be on the surface or underground, it does not matter to the operation of the Nautilus Equipment. If the LHDÆs, trucks, locomotives, etc are automatically guided from origin to destination, the operator is free to operate several vehicles at a time, performing only those tasks which are too difficult for a computer to do by itself.

Jan 1, 1998

By Morrison R

Optimisation has two distinct applications in the concentrator ò the first is in the area of the flowsheet and the operating parameters of the various unit operations ò the second is associated with the higher levels of process control. The Plant Metallurgist is faced with a library of complex theories relating to optimisation. The practical reality of optimisation lies in a combination of steady state simulation to ensure that the process route will permit maximum productivity and an appropriate process control system which will permit achievement of the production and quality objectives.

Jan 1, 1991

An on-stream iron ore analyser has been developed in collaboration with Hamersley Iron Pty. Limited for determining the iron content of both lump (- 30 + 6 mm particle size) and fines (- 6 mm particle size) on conveyor belts. The analyser, which is called IRONSCAN, is based on pair production, and is now commercially available from Mineral Con- trol Instrumentation Limited (MCI) in Adelaide. It can be mounted under existing conveyor belts with minimal modifications to the conveyor struc- ture, and the presence of steel cables in the belt does not interfere once the analyser has been correctly calibrated. The analyser has been exten- sively tested on both lump and fines on the shiploading conveyor at Damp- ier, and typically the root mean square (r.m.s.) deviation between single IRONSCAN measurements and conventional chemical analyses is better than 0.5% Fe. It is currently being evaluated on - 150 mm ore from the primary crusher at Mount Tom Price, and initial results are encourag- ing. The principal advantage of IRONSCAN is that it provides rapid infor- mation on ore grades. But perhaps its greatest potential is at the primary crusher where conventional sampling and analysis is very expensive to Implement. at the University of Melbourne, and those of us who were his students had learnt of the application of physical chemistry to pyrometallurgical processing, pioneered by Chipman in the USA, Wagner in Germany, and Richardson in the UK. It was possible, by applying this theoretical insight to the equilibria between metal, speiss or Legierung, matte and slag phases, to find a practical and effective way to recover metal values in some residues which had been accumulating for many years at the NA, but which had defied all attempts to treat them to that date. There was also an opportunity to study the batch lead refining methods still in use at all lead refineries apart from Port Pirie, and to devise optimis- ing techniques which greatly improved the operations and effected considerable savings. Next the writer spent some six years alternating between the BHAS, Port Pirie, and Imperial Smelting at Avonmouth in the UK, concerned with lead or lead-zinc smelting, and the develop- ment of several further continuous lead refining processes, before returning to Australia as Section Leader, Process Development in the CSIRO Division of Chemical Engineering, Fisherman's Bend, Victoria. Metallurgical opportunities which arose during this last period included the problem of tin smelting which had developed over about a decade: the world's tin smelters had been accustomed to treating fairly high grade tin concentrates, con- sisting of almost pure cassiterite, with very little impurity-mostly quartz, limestone, iron oxides, and sundry other silicates. Most such concentrates had been produced from alluvial deposits, where nature had already done some of difficult part of the mineral processor's work-at who knows what recovery-so that he could now produce high grade concentrates at high recovery. The smelters were not really set up for the treatment of lower grade concentrates, such as could be made with reasonably high recoveries from rock mining. Thus they imposed such penalties on impurities and lower than desired tin grades, that whenever a mineral processor improved tin recovery at the expense of lower- ing grade, such an improvement entailed a lower financial return to the miner. There was clearly a need for improved understand- ing of tin smelting, (at that time shrouded in secrecy) and develop- ment of techniques better suited to the treatment of lower grade concentrates. As well as the practical development, a start was made with the computer modelling of the smelting process, with the obiect of optimising the process parameters.

Jan 1, 1988

By J Sarvinis

The design and operational aspects of fluidised solids transfer-cooling devices will be discussed in this presentation. The devices include air slides and fluoseals (also called seal pots, loop seals, etc), which are widely used in metallurgical plants and other processing plants. Cooling can be achieved while solids are transported in the solids transfer devices. The units combining solids transfer and cooling provide compact and clean plant layouts and also reduce capital and operational costs. Fluidised devices provide excellent gas-to-solids and gas/solids-to-surface heat transfer rates, hence high cooling efficiency. Fluidising gas, such as air, nitrogen or other gases, can be used as direct cooling mediums. Coolants such as water, steam and other liquid or gas cooling fluids can be used as indirect cooling mediums via tube coils immersed in the fluidised solids. The fluidised transport devices share some common features with fluidised bed equipment. The air slide is similar to a linear fluidised bed while the fluoseal is similar to a circular fluidised bed. Therefore fluidised bed design techniques are applicable to the design of the air slides and fluoseals. The heat and mass balance and temperature profiles of the devices concerned will be discussed in the presentation. The design criteria and operational philosophies of the critical components such as tuyeres and air spargers will also be discussed.

Jan 1, 2006

IN presenting the following short paper the writer hopes to illustrate some uses of explosives in industrial work under conditions different to those prevailing on mining fields. This paper is based on experience gained at the Newcastle steel works of the Broken Hill Proprietary Company Limited. The management had decided that as soon as No. 2 blast furnace which is of an improved design was ready to be put into commission, No. 1 blast furpace was to be dismantled and reconstructed to a similar design to No. 2 furnace. This reconstruction entailed the removal of the brick lining of the furnace shaft, and, also the removal and disposal of the,"salamander" and hearth-lining. For the information of members who may possibly be unacquainted with the term "salamander," it might be explained that this term is used by iron metallurgists to denote the mass of iron and slag formed at the- bottom of the furnace, whilst in commission.The method of disposal depends upon the size and nature of the salamander, and in the case under review it was decided to bury it below the hearth of the 'furnace' to be reconstructed. A passage-way was made in the concrete walls of the cast house, and the sand-filling of the cast house removed sufficiently to allow of the concrete foundations of the furnace being reached. This passage-way was extended until the hearth was encountered. The next operation was the removal of the hearth-lining below the salamander. The removal of the concrete was not difficult...

Jan 1, 1921

The design of drawpoints in caving and stoping mines has a significant impact on the productivity of the operation. Drawpoints must be designed to provide uniform drawdown and maximum recovery of the broken ore within the limits imposed by the dimensions of the stope, the stability of the pillars, the method of draw, material flow characteristics, etc. The design of drawpoints historically relied on the mining engineerÆs experience and intuition. However, in many operations, empirical analyses have also produced important information regarding design geometry. Factors that affect the sizing and spacing of drawpoints are discussed and guidelines are provided for their design in order to obtain maximum recovery of broken ore and reduce hang-ups.

Jan 1, 2000

Although the 'exi'stence of bauxite in Australia has been known for many years it is only recently that exploitation has commenced.. of the two most' important` deposits, strangely at almost diagonally opposite tips of the continent. Recognition of the importance. of the bauxite in the South/West corner came about initially through the efforts of a well-known Australian mining company which,` with some outside financial help, tackled the early exploration with commendable foresight and courage.

Jan 1, 1964

By G Varley

This paper describes the mining methods and strategy used to extract the 5 Orebody crown pillar at the Isa Lead Mine over the past five years. The bulk of the crown pillar was extracted by the use of sublevel open stope method. An uphole bench stope was mined to scavenge the remaining ore. Geomechanical issues associated with the crown pillar extraction are described. Stope sizes were gradually increased on a stope by stope basis. This has allowed the maximising of ore recovery while relevant risks were managed. The principles in designing ore rib pillars against various types of fill materials are also described.

Jan 1, 2002

By T C. Hughes, R Hughes

Ausmelt has developed and commercialised high temperature reactor technology that has been applied to waste processing in the form of a catalytic waste converter (CWC). Ausmelt Technology uses a top submerged lance system within a versatile converter containing an oxidised molten siliceous slag. Metals and other valuable products can be extracted from wastes for recycle into the community. Non-valuable components such as toxic organochlorinated compounds are destroyed and prevented from reforming. The slag produced is inert and can be safely used in building and concreting. The CWC can be applied to practically all types of wastes and examples from Ni-Cd batteries to toxic wastes are discussed. Additional benefits can be derived from large-scale operations if the surplus heat generated is exploited to produce steam and electricity.

Jan 1, 2000

By G L. Boyd

Backfill applied to highwall mining is foreseen as a means to increase recovery of mineable coal to levels comparable with underground longwall mining. This paper describes the progress of research to demonstrate the role required of backfill to achieve real increases in coal recovered by highwall mining methods.

Jan 1, 1998