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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 M Surtees

The Limpopo region in southern Africa is considered to be a favourable target for the discovery of base and precious metal mineral deposits. The integration of gravity, geomagnetic, LANDSAT data and geotectonic history is used to formulate an ore deposit model which can be used in the implementation of mineral exploration programmes. Field work was carried out to test and refine the model.

Jan 1, 1993

The word governing derives from gubernare meaningto pilot a ship. Being inclined to metaphors, one could be forgiven to think that politicians act this verb and captain the Nation's ship into some definite course. In the case of at least the mineral resources industry, it seems that there are not many James Cook followers in our parliaments: Australia's approach to mineral and energy policy is often chaotic - witness the 1935 to 1961 ban on iron ore export-ing which prevented the development of a significant steel industry at time when the World was hungry for this metal, just to mention one amongst many other examples.The follies of Australia's mineral policies are well il-lustrated in the case of uranium mining. Although Australia had the Western World's largest economic reserves of uranium, it is onlythefifth producing nation and its uranium potential is largely unrealised. At the root of this situation are the interventionist attitudes and policies of successive Federal Governments which for more than four decades distorted the Investment decision and, in more recent times. discouraaed investment.

Jan 1, 1990

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

Pyrite is a significant gangue sulphide mineral in the Ok Tedi copper ore. Its presence in the flotation concentrate is not entirely desirable since it lowers the grade of the final copper concentrate. Lime depression of the pyrite has been practiced with some success. However, it has been observed that at the pH for pyrite depression a significant amount of the pyrite particles still float. To obtain further insight into the problem this work has been conducted to determine the composition, natural floatability and xanthate flotation behaviour of the various types of pyrite in the ore. The flotation results show that while some types of pyrite float well at high pH values, others are readily depressed. The implications of these results for Ok Tedi flotation plant have been Considered.

Jan 1, 1997

By Bennet A. G

An overall review of the selection of rock strength and deformation characteris- tics for the design of the Melbourne Under- qround Rail Loop (MIJRL) rock tunnels is presented. Particular emphasis is placed on aspects of in-situ testing, including large diameter plate bearing tests. Material on the interpretation of test results for use in the design of the tunnel linings and openings is included, with a brief discus- sion of desiqn methods.

Jan 1, 1981

By Fulton E, Ring RJ, Waters DJ

Laboratory leach tests of Nabarlek uranium ore carried out by the Australian Atomic Energy Commission to compare the effectiveness of Caro's Acid1 (permonosulphuric acid) as an alternative oxident to pyrolusite indicated reduced acid consumption in leaching and lime savings in neutralisation of tailings liquors when using Caro's Acid. Interox Chemicals Pty. Ltd. arranged a plant trial for Caro's Acid at Queensland Mines Nabarlek Plant. The trial confirmed that significant savings in acid and lime can be achieved under plant conditions. Plant operations also demonstrated improved redox potential control was possible using Caro's Acid.

Jan 1, 1978

By Floyd JM

Pilot plant trials showed the effective ness of the submerged lance SIROSMELT technology for altering the composition of iron blast furnace slags as a preliminary step to produc- tion of formed materials. Mixtures of oil and air were injected into a bath of liquid slag to provide the heat required for melting the additives and to provide very turbulent conditions which resulted in complete dissol- ution of added fluorspar within one minute and almost complete dissolution of silica in two minutes. Sulphur lost during injection was readily made up by addition of pyrite or pyrrhotite. A stable foam could be readily made and broken down and the foamed slag appeared suitable for extrusion or forming into shapes.

Jan 1, 1979

I must tell you at the outset that I come to this conference deeply disturbed at the `role of Government in international dealings in mineral and energy resources'. I am disturbed by the confusion that now passes for policy. I am disturbed by the short- range view of critical problems taken by a majority of Governments. I am equally disturbed by the even shorter range of view taken by a growing army of industries. Many of them clamour for Governments to solve their problems in a specific way, with little regard for any other sector but their own-and with even less regard for the fact that every time a Government takes over some of their responsibilities they surrender some of their freedom. I would not say that longer range views don't exist. But I would say that they don't prevail at the present time. Instead, we are seeing the con- stant development of many policies for individual problems which don't tackle the fundamental causes. We must get back to basics without delay.

Jan 1, 1978

By C M. Hill

This paper aims to provide a brief overview of the Australian Coal Bed Methane (CBM) industry and more importantly the challenges to sustainable management of the industryÆs by-product, groundwater. In a country where water is scarce and having gone through one of the worst recorded droughts it is vital that this important industry be seen to be managing water in a responsible manner with the greatest environmental and social benefit. Benefits of the water from CBM wells can be enhanced through treatment to produce potable water for domestic or stock purposes, water for irrigation or aquaculture or lower quality or untreated water for industrial or mining purposes. Other options are re-injection of raw water or waste from the treatment processes or discharge to surface waterways. The critical change and difference between CBM projects and traditional oil and gas operations should be that where possible water is no longer disposed of via evaporation ponds with the dual legacy of waste of the water resource and an environmental contamination problem with the remaining salt and brine product.

Jan 1, 2003

The paper describes the reasons for developing, specifically in South Africa, dense medium processes to allow baths to operate at low (about 1,35) and high (about 2,0) cut points. Low density processing was developed to meet the demand for low ash coals; high density processing was developed to enable heavily contaminated raw coals, destined to be burned in captive power stations, to be de-shaled without loss of combustibles. The anticipated and actual technical difficulties of operating baths at such density extremes are described, and the results from operating plants outlined.

Jan 1, 1987

By Yang RL, Bailey ML

During overburden blasting operations in dragline pits, coal edge losses along the lowwall edge of the new pit are often experienced. In tonnage terms, losses can be significant. With the thick seams at Callide Mine, 20,000 tonnes of coal can be lost along a 600 metre pit. In addition to the immediate dollar value of the coal, replacement of this coal (from which overburden has been removed) will be from higher ratio and higher cost pits in the future. Unit costs of production for the remainder of the coal uncovered in the current pit increase. Experiments involving variation of blasthole inclination and/or amount of standoff on the front row of blastholes have given no significant improvement in the coal edge loss control.

Jan 1, 1988

In May 1977 a new dam was commissioned for disposal of 600,000 metric tonnes/year of tailings. Design basis, costs and construction problems are described. Problems arose, assoc- iated with lack of experience in building such a dam "from scratch". Solutions are described land costs given.

Jan 1, 1978

By Townsend IJ

The Upper Triassic Leigh Creek Coal Measures which include a number of seams of sub-bituminous black coal are preserved in four small intramontane basins. The largest is Telford Basin, 1,000 m in thickness. The coals, of variable thickness and quality, are mined by open cast mining methods and utilised for generation of electricity at Port Augusta. The combined proven and indicated reserves are about 100 million tonnes.

Jan 1, 1975

AXTAT is a computerised system developed by the Western Australian Department of Minerals and Energy in conjunction with the local mining industry for recording and retrieving information about fatalities and work related injuries. Since its inception, the system has gained considerable recognition by consistently demonstrating its usefulness as a tool, not only to the Department, but for the entire industry nationwide. AXTAT has played an important role in the continuous improvement process in management of occupational health and safety in the Western Australian mining industry with gains in both human and financial terms, by regularly providing timely and accurate statistical feedback on fatalities and lost time injuries to industry.

Jan 1, 1996

By Lennox A

In an attempt to increase underground productivity Coal and Allied has introduced a continuous haulage unit into it's Moonee colliery. A second unit is planned for Nallarah colliery in the near future. Both systems will be roof mounted or monorail type and manufactured by Joy Manufacturing Pty Ltd. The introduction of these machines is seen as a logical step in improving the efficiency of mining with continuous miners. This could be in conjunction with longwall mining in the rapid development of gate roads or, as in the case with these machines, as conventional development and extraction units. The advantages of the continuous haulage system are; Relatively low cost. 2 Ability to obtain high productivity in irregular or disturbed coal reserves not suitable for longwall mining. 3 Increased worker safety with the elimination of shuttle cars and the majority of trailing cables. 4 Increased productivity independent of soft or difficult floor conditions. At the time of writing the Moonee installation is 6 months old. The Nallarah machine is due for delivery March 1988.

Jan 1, 1988

Evaluation of reserves on a production scale within a shear-hosted gold deposit is complicated by the nature of the mineralisation itself. The 'payable' ground seems to be confined to areas with intense shearing, while the remainder of the deposit is characterised by 'background' mineralisation at a very low level.

Jan 1, 1993

By Kaleta S, McTavish LP, Turner RD

Primary production blasting at Hamers- ley Iron began with seven inch holes at Tom Price in 1966 and has developed since then to large multiple row shots of 381 mm holes at Tom Price and 311 mm at Paraburdoo. Up to 1.3 million tonnes are initiated in a single blast with the average around 300,000 tonnes. Development can be traced through Anfo, AlAnfo, slurries, various boosters, initiation and delay techniques, hole loading and daily operating practices. A standard practice could be developed for the two mines for normal pro- duction blasts; this would not apply to such common variations as low "paddy" shots, pre- splitting, tight corners necessitating single row drilling etc. Because of ground variation three or even four sizes of drill holes may well be economic- al for blasting, even though this would be off set by complications in operation, supervision, store stocking and maintenance, particularly in Drilling.

Jan 1, 1978

The Olympic Dam Mine is a large, mechanised, underground operation currently producing 2.2 million tonnes-per-year of copper/uranium/gold ore. The mine is accessed via one shaft and one service decline. An additional 13 raise bored ventilation shafts have been completed to-date.Ventilation requirements are stringent in order to provide adequate dilution and removal of diesel fumes, radon gas/daughters and heat generated from both engines and wall rock.Due to the nature of the orebodies, the mine workings will continue to expand laterally necessitating the addition of at least one major surface raise every year.

Jan 1, 1992

By Hatherly P, Dunn P

There are- several in-seam coal research projects currently under investigation by the Cooperative Research Centre for Mining Technology and Equipment (CMTE). The overall aim of the projects is to produce new technologies to enhance safety and the efficiency of in-seam gas drainage drilling. Results from high pressure waterjet rotary drilling trials indicate that by applying high pressure water to a rotary drill bit, the hole can be drilled to follow the planned trajectory very closely. Steerable drill bits for drilling long holes (>1 km) have been produced and trialed. A flexible high speed drilling system provides a capacity for rapid in-seam drilling, particularly suited to cross panel drainage. Geophysical tools are being developed to provide a geological steering capability and a better understanding of potential gas outbursts zones.

Jan 1, 1998