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By Braithwaite J. C

A brief summary is given of the applications of geochemistry on two areas in North West Nelson. It has been found to be an effective method for reconnaissance prospecting. Its particular advantage lies in areas which due to thick bush cover or ru

Jan 1, 1980

One of the biggest drawbacks of deciding upon a heap leach method of treating gold ore is the risk associated with the full-scale production heaps not performing as predicted by the testwork. This paper examines the key decisions that are taken in the design of a heap leach project, and suggests ways in which exposure to these risks can be minimised. It also looks at monitoring techniques to give early warning of problems and possible remedial actions.

Jan 1, 1994

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 Gilbert DJ, Lemon NM

A case history of a two year study of low grade ores in the Middleback Range area with the objective of defining possible areas of interest from a combination of geological- petrological-metallurgical criteria. Covering the general geology of the area and ore types; the results of metallurgical testwork and the pattern of evolution of these tests; the petrological explanation of the results of the testwork; the culmination of the work in the selection of areas of best potential for more intensive work. Jaspilites consisting of magnetite, hematite and limonite with quartz and silicate-carbonate-sulphide minerals are hosts to high grade iron mineralisation but also constitute a large low grade iron Reserve.

Jan 1, 1975

Alcoa of Australia's Del Park mining op eration is centred 9 km. east of the Pinjarra alumina refinery, and is centrally locatedwith- in the 10, 000 sq. km. lease which the Company holds for bauxite in the Darling Ranges. An- other mining operation is situated near the township of Jarrahdale, and supplies bauxite to the Kwinana refinery. Definition of the bauxite ore, development works and mining to the ore haulage stage, are identical for both mining operations. Exper- ience, and production cost figures, obtained from the Jarrahdale mine, where 100 tonne trucks are used to haul ore to a fixed crushing plant, led to the development of the Del Park mining concept with increased mobility of op- erations. The crushing-conveying-stockpiling arrangement at Del Park consists of a 1200 t. p. h. mobile crusher feeding bauxite to an overland conveyor system which transports the ore approximately 6. 66 km. to the stockpile area in the refinery. In the refinery raw mat- erials area the bauxite is distributed into 200, 000 tonne stockpiles by means of a travel- ling boom stacker.

Jan 1, 1973

By McAuley T. J

Computer software is an integral part of mining operations today with many sites using six or more software packages on a daily basis. However, the use of these different programs generates the need for substantial staff training. The current trend toward large integrated packages to solve this problem is counter-productive because the relatively small companies producing specialised mining software do not have the resources to develop quality software with all the required features. Software standards are being proposed by various parties but recent history indicates these will be unsuccessful. An alternative approach is suggested using the various standards which have been developed for the Windows operating system.

Jan 1, 1995

FOR some years past it has been usual to specify high-grade copper for use for many purposes, but the practice of specifying zinc of a high degree of purity for certain purposes is of comparatively recent origin. It is a practice, however, which is extending ag the effect of the impurities in zinc on products manufactured therefrom becomes widely recognized.The notes hereunder are intended to briefly survey the principal uses to which high-gr.ade zinc is being put, and, wherever possible, to indicate the effect of the impurities normally present in the lower grades of zinc.In the United States zinc is graded into five divisions, known respectively as "High-grade" "Intermediate" "Brass Special" "Selected," and "Prime Western." The maximum amounts of impurities allowed in the various grades are indicated in Table I,which is compiled from data published by the American Society of Testing Materials:In addition, it is specified in an cases that the slabs shall be reasonably free from surface corrosion or adhering foreign matter. Although zinc used in Europe has in many cases been sold on analysis it is only recently that any attempt has been made to grade...

Jan 1, 1923

From depths of 400 - 600 m, coal is transported by a conveyor in a drift or a bulk winder in a shaft, whilst men and/or materials are transported by a slope hauler or a cage winder. Assessment of the effect of alternative combinations on the key cost factors - output, capital, labour cost and construction time - allows the optimum choice for particular circumstances, there being no uniform solution.

Jan 1, 1976

The design of a sand pump is similar in principle to that of a water pump but differs in several areas. Results of experiments on sand pump performance have been summarized and values of design parameters quoted for optimum results. Typical performance data are also Included.

Jan 1, 1973

The Ardlethan tin concentrator had dete riorated considerably in metallurgical per- formance, maintenance and plant availability. This problem was compounded by low tin prices and International Tin Council quotas. Mid- 1976 figures were: throughput - 1300 tonnes per day, availability 83% and metal recovery 537. Major problems existed throughout the circuit from crushing to tailings disposal and with morale, staffing, and housekeeping. With the lifting of the quotas in June 1976, management provided funds to implement a major rehabilitation programme and some fifteen major projects, at a cost of about $1.3 million have been completed to date. The change in performance has been dram- atic, and end of 1977 performance figures are: throughput - 1700 tonnes per day, availability 90% and metal recovery 65%.

Jan 1, 1978

Gunpowder Copper Limited processes 1,000 tonne/day of Mammoth ore in a conventional flot- ation concentrator. Run of mine ore is prepared for flotation by three stages of crushing and two stages of ball milling. The concentrate, in which the primary copper mineral is chalcocite, is solar dried and exported to Japan. The history of operation is summarised, and plant practice and metallurgical problems are discussed.

Jan 1, 1974

By McLaughlin R. G, Brammer R. A J

King Island Scheelite had been using dealer modified front end loaders for two years when in 1974 it started to increase production. Suppliers were then quoting long deliveries for underground diesel trackless mining equip- ment, and the Company was forced to modify surface machines which had become redundant as production from the open cut phased out. The results were generally successful and encouraged further adaptations. Drill jumbos excepted, the Company now uses only converted surface machines in areas worked by diesel engined equipment and for all support and auxiliary functions.

Jan 1, 1977

This paper reviews the commissioning and operation of the process plant at Tolukuma over the past 18 months. The plant treats a high-grade gold and silver ore through a SAG mill followed by a conventional carbon-in- leach (CIL) circuit. Gold is

Jan 1, 1997

The evolution of Hall process alumina reduction technology is des- cribed with particular attention to the pot lines. Future directions of tech- nological change are considered. It is predicted that the Hall process will continue to be the avenue for aluminium production for some time to come.

Jan 1, 1982

By Walters GW

A countercurrent method of metal refining using crystallization and reflux is discussed. 4n account is given of the development of this technique for the separation of silver and bismuth from lead using bench-scale studies to the present small pilot-plant unit (around one tonne per day) in the "Commonwealth Scientific and Industrial Research Organization (CSIRO)" Division of Chemical Engineering.

Jan 1, 1975

Over the past 12 years screening of materials has undergone a dramatic change in both the types and materials used in screen mats and the quality requirements of the finished product. With the main thrust now on quality and a cleaner product a different approach was needed in the operation of sizing screens. New screen mats with many different aperture configurations have been developed using rubber and plastics.to replace the traditional screen mat of woven wire or punched plate.

Jan 1, 1984

Welcome to Mount Isa- my home city and without doubtthe base for what promises to be the most exciting mineral development yet seen in Australia.Mr. Chairman, it also gives me great pride to representthis area in the Queensland State Parliament as well as being the Minister for Minerals and Energy in the Queensland Government.Mount Isa is now part of the Australian mining industry folklore.It is all what a good mine is all about. It is. all what a good community is all about.

Jan 1, 1993

By Anylmore M, Walker A, Fletcher A

Roasting of sulphide and sulph-arsenide gold ores produces unwanted emission of sulphur and arsenic oxides, and a less than complete recovery of gold. Pyrite loses sulphur and arsenopyrite loses arsenic at a useful rate at temperatures of 600¦C and above in an inert atmosphere. Sulphur and arsenic driven off can be condensed before entering the atmosphere. During the process, solid-solution gold redistributes itself on internal surfaces of the resulting iron sulphide. Two subsequent processing options may be used; direct cyanidation of the porous sulphide resulting from the anoxic pyrolysis, or a second-stage roast to oxidise the remaining iron sulphide. The first option may be viable under certain conditions of pyrolysis. The two-stage option has an environmental advantage over the traditional roast because it reduces oxide vapour emissions by 50 per cent. The second stage may provide nearly enough energy to sustain the entire process.

Jan 1, 1992

By B Lindqui, M V. Knyazev, L S. Tsemekhman

Gipronickel Institute JS that is a Research and Development Centre affiliated to the worldclass Norilsk Nickel Mining and Metallurgical Company, and Outokumpu Technologies AB (Boliden Contech AB) have jointly developed the reconstruction project of Pechenganickel metallurgical operations using a two-zone Vanyukov furnace. The international expert group appointed by the Nordic Investment Bank has examined the project. The project financing should be partly executed by the Norway government. Current annual rate of sulfur dioxide emissions is 100 000 t. The aim of the project is to reduce it to 12 000 tpy. Pechenganickel Combine is owned by MMC Norilsk Nickel. Currently it produces nickel high-grade matte from sulfide copper-nickel concentrate with up to ten per cent MgO content. The existing production is in accordance with the following flow sheet: agglomeration û electric furnace smelting with matte production û converting in horizontal converters. Annual production capacity is about 36 000 t of nickel in high-grade matte. Converter gases report to sulfuric acid production. The principal results of studies on high magnesia materials smelting in two-zone Vanyukov furnace, engineering solutions, and technical and economical parameters are offered.

Jan 1, 2004

IT is very difficult for a founder engaged in jobbing work, comprising all sizes and classes of castings, to appreciate that the analysis of the iron he is using cannot entirely fill the situation he desires for his varied classes of work. Neither is there any panacea in the shape of an iron mixture that will suit the whole of his floor for the day.From his own experience he generally alters his cupola charges during the cast, endeavouring to meet at the same time the requisite metal composition for the castings he is about to pour.The founder on repetition work is in a much better position to stabilise his methods, arrive at a certain pig-iron' analysis, regulate...

Jan 1, 1926