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The application of cheap robust microprocessor based units to achieve monitoring and control in an underground mining environment is described. The functional layout of the programmable controller and the methods of multiplexing and processing information from local and remote sources are examined as are features for refrigeration plant control.High noise immunity communication to a remote micro computer uses existing telephone lines and enables display and print of essential data. The development of this system then leads to applications in monitoring compressed air, ore transport and underground fires.In conclusion, the problems of data presentation to different levels of management and the future philosophy of a central multi-reporting system are discussed.

Jan 1, 1985

By Sakurai F

Akita Zinc Refinery of Mitsubishi Metal Corporation (MMC) started operation in 1953 with a capacity of 560 tons of electrolytic zinc per month. Its capacity has been expanded gradually and reached 8,100 tons per month in 1973. However, present production level is about 6,500 tons per month due to the depressed zinc market. In 1963, newly developed sulphate roasting was incorporated for residue treatment. Since 1973, electric power from Ohnuma geothermal power station of MMC has been supplied in addition to hydroelectric power from Komata power station of MMC. At present, about 40% of power is supplied from our company's power station and the rest is from the power company. Recent customers' demands for zinc prod- ucts include various kinds of shape, weight and chemical composition of galvanizing zinc alloy. It is necessary for zinc producer not only to meet the requirements of customers but also to enhance the value of zinc product in order to expand the market of zinc.

Jan 1, 1987

A relationship is predicted between oxidic nickel in slag, oxygen in matte and Ni/Fe ratio in matte after the examination of thirty sets of contiguous matte and slag samples taken from industrial nickel smelters. Oxidic nickel in slag is found to increase with increase in oxygen content of matte of constant Ni/Fe ratio, and it is proposed that the relationship may be used to predict nickel solubility in slag from a knowledge of matte composition alone.

Jan 1, 1979

The selection of an appropriate mining method should take into account the geometry of the deposit and its physical properties. Other factors which assist in the determination are the requirements for flexibility in the mining process, minimisation of risk factors and maximising the financial return. Several established mining methods exist which can encompass the requirements to deliver the optimum mining method, this can be in both an underground or open cut environment. The objective is to outline these methods and where they can be applied in a mining project.

Jan 1, 1997

This paper provides a brief fundamental insight regarding the fabric media concept for liquor filtration. The subject matter will be of interest to metallurgists and engineers with professional responsibility for world class design of solid liquid separation processes and efficient lowest cost operation of existing mineral process plant. Avocet Mining commissioned the worldÆs first mineral liquor clarification process incorporating a fabric media liquor filter at their Lanut gold mine in Sulawesi, in 2004 with design consulting provided by the Australian company SLS Technology Pty Ltd. Development of the technology continues with applied research focused on selecting textile parameters to apply filtration to a wider range of particle and contaminant types, higher solids concentrations, and different process liquors. Liquor filtration with the Fabric Media technology offers an array of attractive benefits. For Avocet Mining, filtration of pregnant liquor directly from the heap leach pad has enabled removal of the sediment pond and sand filters from the traditional process flow sheet, thus providing significant cost and installation time savings. Avocet Mining has recently expressed confidence in the technology indicating selection preference of the technology for the expansion at Lanut and for a new project. The application design window for the Fabric Media concept is extremely flexible with the technology now successfully applied to many different liquor chemistries and application objectives around the world. Potential cost savings for solid liquid separation process plant, such as counter current decantation circuits, clarifier vessels and thickener tanks can be calculated from laboratory measurements or pilot plant demonstrations.

Jan 1, 2008

The paper reviews some characteristic features of feasibility studies and discusses the need for a wide scope at the pre-feasibility stage. The performance of recent Australian gold mines against the predictions contained in their respective feasibility studies is examined, resulting in a recommendation that feasibility studies need to be improved The advantages to be gained from having a feasibility study reviewed by an independent authority are discussed, and some of the reasons for using consultants are listed. Two examples of successful optimisations in the early stages of pre-development studies are described briefly and the benefits achieved are presented. The paper concludes that feasibility studies need improvement to enhance the confidence of investors in the mining industry.

Jan 1, 1991

By Dhawan AK

On 8 July 1993, a landslide of about one million cubic metres of rock blocked the river Satluj near Sanjay Vidyut Pariyojana - Bhaba project and caused flooding into the Bhaba Power House (120 MW) resulting in suspension of power generation. The concerned authorities desired an early removal of the blockade by an underwater blasting operation into the over topping water to reduce the water level at the blockade and resume power generation in the power house. In the absence of underwater drilling, it was essential for the blasting technique to be used where no cavity to confine the explosive was required. For this reason mud capping and plaster shooting with directional throw were used and additional specially fabricated mild steel pipe charges were used under high current for an underwater trenching operation. By employing these techniques the river blockade was removed up to the required depth and on 8 September 1993 the Power House resumed the power generation.

Jan 1, 1995

By K M. Watling, F M, G K. Parker

Surface enhanced Raman scattering (SERS) spectroscopy at surfaces under electrochemical control has been applied to elucidate the adsorption of thiol collectors. SERS spectroelectrochemical studies at coinage metal electrodes have been carried out on ethyl xanthate and three iso-xanthates, O-isopropyl-N-ethylthionocarbamate, 2-mercaptobenzothiazole, diisobutyl- dithiophosphinate and butylethoxycarbonylthioura. For each collector, adsorption occurs via charge transfer to form a metal-sulfur bond and, in situations for which the reversible potential of the formation of the bulk phase is known, at underpotentials.

Jan 1, 2005

By OÆBrien D. R

Up until June 1988, Mount Thorley Coal Handling and Preparation Plant disposed of tailings by two methods. Approximately half of the plant tailings was mechanically dewatered by solid bowl centrifuges mixed with plant reject and was subsequently disposed in mine overburden spoils; the remainder was pumped to tailings ponds. Both future mine planning and environmental constraints could not allow for the long term construction of more tailings ponds so, following evaluation of available dewatering technology, belt press filters were selected for the treatment of tailings in excess of the capacity of the existing solid bowl centrifuges. Commission of the four 2.5 metre wide belt press filters soon showed that marked differences in performance were experienced when treating different coal seams. Further analysis showed that the coal tailings from different seams were quite different in terms of clay mineralogy, and these differences could be correlated with varying degrees of filter performance. Poor filter performance was experienced with coal tailings rich in sodium montmorillinite clays. A number of variables were investigated including in-line mechanical mixing of flocculant and feed slurry, cation exchange reagents such as gypsum, and upstream addition of cationic flocculant. In order to achieve satisfactory performance on the worst tailings, a combination of all of the above was required. In this paper, the reasons for selection of belt press filters and the program of investigations and testwork required to arrive at satisfactory belt press filter performance for the treatment of troublesome bentonitic rich tailings are discussed.

Jan 1, 1989

By Bedford D. J

The post pillar cut and fill stoping method has been adopted by King Island Scheelite for the extraction of the main Dolphin orebody. The orebody is a massive, tabular deposit varying from 10 to 50 metres in thickness, and dipping at approximately 30¦ towards and under the sea bed. The mining method was selected for 1. maintenance of hangingwall support under the sea bed; 2. maximisation of first stage ore extraction; 3. flexibility of mining, allowing maintenance of grade and selective mining around waste bands within the orebody, and 4. compatibility of existing equipment both with stoping and the on-going underground mine development programme. Stope parameters were established on the basis of initial rock stress analyses, and since the undercut phase of mining the stoping programme has been monitored with various types of deformation measuring devices installed in a series of large diameter boreholes.

Jan 1, 1977

By Just GD, Phillips R

The application of high pressure water jet technology to the drilling of longholes in coal has resulted in the development of a system currently capable of drilling to lengths greater than 200m. Field tests at the German Creek Mine have demonstrated directional control of the holes within a 0.5m section of the seam. Initial application of the technique at the German Creek operations is for drilling methane drainage holes. These developments, in three stages, result from support by the National Energy Research Development and Demonstration Council

Jan 1, 1991

Among the various methods of thick-seam mining already well-tried in practice longwall caving with extraction of a single slice, as thick as possible, abandoning the top and/or the bottom coal, seems to be the most suitable one for the Australian coal mining industry. The production units of the future should be equipped with heavy double-drum shearer-loaders, wide armoured conveyors, (with one or two central chains) and shield support. Material of this type has been developed for seams up to 6 m thick. Output figures of more than 6,000 tROM/d from a single face can be looked upon as a quite realistic expectation. The problems of co-ordinating such large production units with the whole layout of the mine are discussed. The factors to be taken into account in the planning work and for preven- tion of mine fires caused by spon- taneous combustion are dealt with. For economic reasons the highest possible utilization factor of the very expensive equipment must be aimed at. Furthermore, the seams or parts of seams to be extracted should be carefully selected.

Jan 1, 1976

The introduction of new technology into thegold-mining industry has been encouraged in recent years by increases in the price of gold andthe necessity for costs to be contained.At most new gold mines, run-of-mine millingis preferred over crushing and multistage milling, and this change at the head of the circuit leaves no place for the manual sorting of ore and for gravity concentration in the mill circuit.Flotation continues to hold its place in goldrecovery. However, a decline in the demand forsulphuric acid may limit the amount of pyrite thatcan be roasted before cyanidation.

Jan 1, 1984

To the layman or the casual in- vestor, the critical problems in the mining industry appear to rest on the questions of finding and developing an orebody. The high cost of finding a major orebody suggests that the search is the only matter of real concern. However, the resulting operations which hopefully will provide a profit- able return, depend very heavily on the quality of the servicing that the particular industry receives. Once the mining venture has been established with the necessary plant, equipment and infrastructure, the routine servicing becomes an important function of the operations.

Jan 1, 1975

By P Rourke

In this climate of increasing demand for commodities, it is becoming necessary to expand and optimise existing bulk material handling facilities in order to increase capacity to satisfy demand. Production capacity in these facilities is often adversely impacted during the expansion process. A successful and proven strategy to reduce this impact is to bring the additional capacity online in stages coinciding with routine maintenance or other short shutdowns. Compatibility of the automation systems with staged upgrades in capacity is the key to achieving a successful outcome. Since 1994, Hatch has been researching a generic, highly configurable product transport control system that can be reconfigured to cater for plant expansions or modifications without incurring significant risk to production capacity. In 2002, BHP Billiton Iron Ore (BHPB IO) recognised the need for such a generic Route Selection and Sequencing (RSS) system and engaged Hatch to build a generic RSS system as part of the $US351 million BHPB IO Products and Capacity Expansion (PACE) project. In 2004, Hatch successfully deployed such a generic configurable control system at BHPB IO Port Hedland Ore Handling Facility. This generic system is known as the Hatch Product Transport (HPT) System.

Jan 1, 2005

By Floyd JM, Bultitude-Paul J

The development of a process for the extraction of antimony from materials produced by Greenbushes Tin Limited has been carried out based on theoretical and laboratory studies. The materials treated have included concentrates of tantalite and cassiterite containing antimony at levels ranging from 0.3% to 2%. Roasting under controlled atmospheres is required to stabilise Sb203 rather than the low vapour pressure metal or higher oxide. Sulphidising additives such as pyrite, pyrrhotite or sulphur give enhanced antimony removal from tantalite and cassiterite at roasting temperatures of 900¦ to 1100¦C. Substantial elimination of antimony to levels of 0.1% or less was Achieved.

Jan 1, 1986

The city of Kalgoorlie-Boulder is located 595 kilometres east of Perth in Western Australia, and has a population of just over 30 000. Western Australia's third largest city lies on one of the richest goldfields in the world, with over 45 million ounce

Jan 1, 1998

By C Hertle, B Goebel, R Fabre

The mining industry maintains a ælove-hateÆ relationship with water. Dewatering, aquifer, water disposal, irrigation, process water, tailings water, run-off water, seepage, leachate and sumps are all terms that are used on a daily basis in the mining industry, highlighting the numerous water usages on site and their associated quality. According to the Australian Bureau of Statistics (2001), each year the mining industry consumes over 530 000 ML of water. The increasing recognition of water as a limited and valuable commodity, and the associated environmental concerns with the management of water disposal to the environment has led the industry into improving on-site water management. Progressively, water balance models and water reuse strategies are being developed, incorporating more sophisticated water treatment processes. By way of example, membrane technologies, once restricted to industries such as the pharmaceutical industry or the drinking water industry, are now entering the mining world with the aim of producing clean water of suitable quality for ore processing or for advanced treatment prior to release to the environment. This paper will provide a review of the threats and opportunities linked to water use and recovery/reuse in the mining industry in Australia. It will open with an overview of current water usage and associated quality for various mineral industries and continue with identifying the threats and limitations associated with the quality of available water. It will then present how newly developed water treatment technologies and assessment tools can be incorporated into the system to enhance the recovery and reuse of water on site, reduce the risks associated with securing long-term water supply and further improve production, environment and safety (health risk control).

Jan 1, 2006

By Lawson F

Synthetic calaverite (Au Tez) has been prepared and its physical properties checked.Simple flotation tests indicate that the recovery of calaverite should be possible using n-butyl or sec-butyl xanthate collectors under approximately pi I neutral conditions with a copper sulphate activator.Roasting calaverite in air at moderate temperatures resulted in its decomposition with the formation of elemental gold and tellurium dioxide.In alkaline oxygenated cyanide solutions, both gold and tellurium tend to dissolve. At pHs less than 14, about 50 per cent of the tellurium remains as elemental tellurium; however in very strongly alkaline solutions, essentially all of the tellurium is converted to the soluble tellurite ion (TeOl-).However, even at high pHs, the solubility of gold in the cyanide solution is still low due almost certainly to passivation effects.

Jan 1, 1991

Flat jack stress determinations in selected colliery roadways have revealed a range of measured stress from 330-p.s.i. tension to 3,750 p.s.i. compression. Photoelastic examination of loaded plastic and actual rock mo.odel mine openings has shown that the primary horizontal stress required to attain these measured stresses would be from one to three times the superincumbent vertical load.Examination of roof movement with a. borehole oxtensumeter and a series of anchors at various horizons to 30 feet in a. vertical roof borehole showed that when a standing face waa.s advanced the roofmovement was practically confined to the lower two feet. The ma.j ority of this movement occurred during the 36 hours after mining at this face commenced.The use of a. radioactive isotope and a. scintillation counter in a. pair of parallel bcreholes promises to be sensitive and accurate method of roof bedding plane crack detection.

Jan 1, 1963